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};
13 use bitcoin::hashes::Hash;
14 use bitcoin::hashes::sha256::Hash as Sha256;
16 use crate::blinded_path::{BlindedHop, BlindedPath};
17 use crate::blinded_path::payment::{ForwardNode, ForwardTlvs, PaymentConstraints, PaymentRelay, ReceiveTlvs};
18 use crate::ln::PaymentHash;
19 use crate::ln::channelmanager::{ChannelDetails, PaymentId};
20 use crate::ln::features::{BlindedHopFeatures, Bolt11InvoiceFeatures, Bolt12InvoiceFeatures, ChannelFeatures, NodeFeatures};
21 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
22 use crate::offers::invoice::{BlindedPayInfo, Bolt12Invoice};
23 use crate::onion_message::{DefaultMessageRouter, Destination, MessageRouter, OnionMessagePath};
24 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
25 use crate::routing::scoring::{ChannelUsage, LockableScore, ScoreLookUp};
26 use crate::sign::EntropySource;
27 use crate::util::ser::{Writeable, Readable, ReadableArgs, Writer};
28 use crate::util::logger::{Level, Logger};
29 use crate::util::chacha20::ChaCha20;
32 use crate::prelude::*;
33 use crate::sync::Mutex;
34 use alloc::collections::BinaryHeap;
38 /// A [`Router`] implemented using [`find_route`].
39 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> where
41 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
45 random_seed_bytes: Mutex<[u8; 32]>,
48 message_router: DefaultMessageRouter<G, L>,
51 impl<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> DefaultRouter<G, L, S, SP, Sc> where
53 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
55 /// Creates a new router.
56 pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S, score_params: SP) -> Self {
57 let random_seed_bytes = Mutex::new(random_seed_bytes);
58 let message_router = DefaultMessageRouter::new(network_graph.clone());
59 Self { network_graph, logger, random_seed_bytes, scorer, score_params, message_router }
63 impl<G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> Router for DefaultRouter<G, L, S, SP, Sc> where
65 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
70 params: &RouteParameters,
71 first_hops: Option<&[&ChannelDetails]>,
72 inflight_htlcs: InFlightHtlcs
73 ) -> Result<Route, LightningError> {
74 let random_seed_bytes = {
75 let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
76 *locked_random_seed_bytes = Sha256::hash(&*locked_random_seed_bytes).to_byte_array();
77 *locked_random_seed_bytes
80 payer, params, &self.network_graph, first_hops, &*self.logger,
81 &ScorerAccountingForInFlightHtlcs::new(self.scorer.read_lock(), &inflight_htlcs),
87 fn create_blinded_payment_paths<
88 ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification
90 &self, recipient: PublicKey, first_hops: Vec<ChannelDetails>, tlvs: ReceiveTlvs,
91 amount_msats: u64, entropy_source: &ES, secp_ctx: &Secp256k1<T>
92 ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()> {
93 // Limit the number of blinded paths that are computed.
94 const MAX_PAYMENT_PATHS: usize = 3;
96 // Ensure peers have at least three channels so that it is more difficult to infer the
97 // recipient's node_id.
98 const MIN_PEER_CHANNELS: usize = 3;
100 let network_graph = self.network_graph.deref().read_only();
101 let paths = first_hops.into_iter()
102 .filter(|details| details.counterparty.features.supports_route_blinding())
103 .filter(|details| amount_msats <= details.inbound_capacity_msat)
104 .filter(|details| amount_msats >= details.inbound_htlc_minimum_msat.unwrap_or(0))
105 .filter(|details| amount_msats <= details.inbound_htlc_maximum_msat.unwrap_or(0))
106 .filter(|details| network_graph
107 .node(&NodeId::from_pubkey(&details.counterparty.node_id))
108 .map(|node_info| node_info.channels.len() >= MIN_PEER_CHANNELS)
111 .filter_map(|details| {
112 let short_channel_id = match details.get_inbound_payment_scid() {
113 Some(short_channel_id) => short_channel_id,
116 let payment_relay: PaymentRelay = match details.counterparty.forwarding_info {
117 Some(forwarding_info) => forwarding_info.into(),
121 // Avoid exposing esoteric CLTV expiry deltas
122 let cltv_expiry_delta = match payment_relay.cltv_expiry_delta {
130 let payment_constraints = PaymentConstraints {
131 max_cltv_expiry: tlvs.payment_constraints.max_cltv_expiry + cltv_expiry_delta,
132 htlc_minimum_msat: details.inbound_htlc_minimum_msat.unwrap_or(0),
139 features: BlindedHopFeatures::empty(),
141 node_id: details.counterparty.node_id,
142 htlc_maximum_msat: details.inbound_htlc_maximum_msat.unwrap_or(0),
145 .map(|forward_node| {
146 BlindedPath::new_for_payment(
147 &[forward_node], recipient, tlvs.clone(), u64::MAX, entropy_source, secp_ctx
150 .take(MAX_PAYMENT_PATHS)
151 .collect::<Result<Vec<_>, _>>();
154 Ok(paths) if !paths.is_empty() => Ok(paths),
156 BlindedPath::one_hop_for_payment(recipient, tlvs, entropy_source, secp_ctx)
157 .map(|path| vec![path])
163 impl< G: Deref<Target = NetworkGraph<L>> + Clone, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> MessageRouter for DefaultRouter<G, L, S, SP, Sc> where
165 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
168 &self, sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
169 ) -> Result<OnionMessagePath, ()> {
170 self.message_router.find_path(sender, peers, destination)
173 fn create_blinded_paths<
174 ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification
176 &self, recipient: PublicKey, peers: Vec<PublicKey>, entropy_source: &ES,
177 secp_ctx: &Secp256k1<T>
178 ) -> Result<Vec<BlindedPath>, ()> {
179 self.message_router.create_blinded_paths(recipient, peers, entropy_source, secp_ctx)
183 /// A trait defining behavior for routing a payment.
184 pub trait Router: MessageRouter {
185 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
187 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
188 /// and [`RouteParameters::final_value_msat`], respectively.
190 &self, payer: &PublicKey, route_params: &RouteParameters,
191 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
192 ) -> Result<Route, LightningError>;
194 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
196 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
197 /// and [`RouteParameters::final_value_msat`], respectively.
199 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
201 fn find_route_with_id(
202 &self, payer: &PublicKey, route_params: &RouteParameters,
203 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
204 _payment_hash: PaymentHash, _payment_id: PaymentId
205 ) -> Result<Route, LightningError> {
206 self.find_route(payer, route_params, first_hops, inflight_htlcs)
209 /// Creates [`BlindedPath`]s for payment to the `recipient` node. The channels in `first_hops`
210 /// are assumed to be with the `recipient`'s peers. The payment secret and any constraints are
212 fn create_blinded_payment_paths<
213 ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification
215 &self, recipient: PublicKey, first_hops: Vec<ChannelDetails>, tlvs: ReceiveTlvs,
216 amount_msats: u64, entropy_source: &ES, secp_ctx: &Secp256k1<T>
217 ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()>;
220 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
222 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
225 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
226 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Deref> where S::Target: ScoreLookUp {
228 // Maps a channel's short channel id and its direction to the liquidity used up.
229 inflight_htlcs: &'a InFlightHtlcs,
231 impl<'a, S: Deref> ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
232 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
233 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
234 ScorerAccountingForInFlightHtlcs {
241 impl<'a, S: Deref> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
242 type ScoreParams = <S::Target as ScoreLookUp>::ScoreParams;
243 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
244 let target = match candidate.target() {
245 Some(target) => target,
246 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
248 let short_channel_id = match candidate.short_channel_id() {
249 Some(short_channel_id) => short_channel_id,
250 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
252 let source = candidate.source();
253 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
254 &source, &target, short_channel_id
256 let usage = ChannelUsage {
257 inflight_htlc_msat: usage.inflight_htlc_msat.saturating_add(used_liquidity),
261 self.scorer.channel_penalty_msat(candidate, usage, score_params)
263 self.scorer.channel_penalty_msat(candidate, usage, score_params)
268 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
269 /// in-use channel liquidity.
271 pub struct InFlightHtlcs(
272 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
273 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
274 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
276 HashMap<(u64, bool), u64>
280 /// Constructs an empty `InFlightHtlcs`.
281 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
283 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
284 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
285 if path.hops.is_empty() { return };
287 let mut cumulative_msat = 0;
288 if let Some(tail) = &path.blinded_tail {
289 cumulative_msat += tail.final_value_msat;
292 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
293 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
294 // the router excludes the payer node. In the following lines, the payer's information is
295 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
296 // in our sliding window of two.
297 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
298 .map(|hop| hop.pubkey)
299 .chain(core::iter::once(payer_node_id));
301 // Taking the reversed vector from above, we zip it with just the reversed hops list to
302 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
303 // the total amount sent.
304 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
305 cumulative_msat += next_hop.fee_msat;
307 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
308 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
309 .or_insert(cumulative_msat);
313 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
315 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
317 .entry((channel_scid, source < target))
318 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
319 .or_insert(used_msat);
322 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
324 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
325 self.0.get(&(channel_scid, source < target)).map(|v| *v)
329 impl Writeable for InFlightHtlcs {
330 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
333 impl Readable for InFlightHtlcs {
334 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
335 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
336 Ok(Self(infight_map))
340 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
341 /// that leads to it.
342 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
343 pub struct RouteHop {
344 /// The node_id of the node at this hop.
345 pub pubkey: PublicKey,
346 /// The node_announcement features of the node at this hop. For the last hop, these may be
347 /// amended to match the features present in the invoice this node generated.
348 pub node_features: NodeFeatures,
349 /// The channel that should be used from the previous hop to reach this node.
350 pub short_channel_id: u64,
351 /// The channel_announcement features of the channel that should be used from the previous hop
352 /// to reach this node.
353 pub channel_features: ChannelFeatures,
354 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
355 /// If this is the last hop in [`Path::hops`]:
356 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
357 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
359 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
361 /// The CLTV delta added for this hop.
362 /// If this is the last hop in [`Path::hops`]:
363 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
364 /// * otherwise, this is the CLTV delta expected at the destination
366 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
367 pub cltv_expiry_delta: u32,
368 /// Indicates whether this hop is possibly announced in the public network graph.
370 /// Will be `true` if there is a possibility that the channel is publicly known, i.e., if we
371 /// either know for sure it's announced in the public graph, or if any public channels exist
372 /// for which the given `short_channel_id` could be an alias for. Will be `false` if we believe
373 /// the channel to be unannounced.
375 /// Will be `true` for objects serialized with LDK version 0.0.116 and before.
376 pub maybe_announced_channel: bool,
379 impl_writeable_tlv_based!(RouteHop, {
380 (0, pubkey, required),
381 (1, maybe_announced_channel, (default_value, true)),
382 (2, node_features, required),
383 (4, short_channel_id, required),
384 (6, channel_features, required),
385 (8, fee_msat, required),
386 (10, cltv_expiry_delta, required),
389 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
390 /// their [`Bolt12Invoice`].
392 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
393 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
394 pub struct BlindedTail {
395 /// The hops of the [`BlindedPath`] provided by the recipient.
397 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
398 pub hops: Vec<BlindedHop>,
399 /// The blinding point of the [`BlindedPath`] provided by the recipient.
401 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
402 pub blinding_point: PublicKey,
403 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
404 /// inferring the destination. May be 0.
405 pub excess_final_cltv_expiry_delta: u32,
406 /// The total amount paid on this [`Path`], excluding the fees.
407 pub final_value_msat: u64,
410 impl_writeable_tlv_based!(BlindedTail, {
411 (0, hops, required_vec),
412 (2, blinding_point, required),
413 (4, excess_final_cltv_expiry_delta, required),
414 (6, final_value_msat, required),
417 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
418 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
419 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
421 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
422 pub hops: Vec<RouteHop>,
423 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
424 pub blinded_tail: Option<BlindedTail>,
428 /// Gets the fees for a given path, excluding any excess paid to the recipient.
429 pub fn fee_msat(&self) -> u64 {
430 match &self.blinded_tail {
431 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
433 // Do not count last hop of each path since that's the full value of the payment
434 self.hops.split_last().map_or(0,
435 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
440 /// Gets the total amount paid on this [`Path`], excluding the fees.
441 pub fn final_value_msat(&self) -> u64 {
442 match &self.blinded_tail {
443 Some(blinded_tail) => blinded_tail.final_value_msat,
444 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
448 /// Gets the final hop's CLTV expiry delta.
449 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
450 match &self.blinded_tail {
452 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
457 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
458 /// it can take multiple paths. Each path is composed of one or more hops through the network.
459 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
461 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
462 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
464 pub paths: Vec<Path>,
465 /// The `route_params` parameter passed to [`find_route`].
467 /// This is used by `ChannelManager` to track information which may be required for retries.
469 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
470 pub route_params: Option<RouteParameters>,
474 /// Returns the total amount of fees paid on this [`Route`].
476 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
477 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
478 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
480 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
481 pub fn get_total_fees(&self) -> u64 {
482 let overpaid_value_msat = self.route_params.as_ref()
483 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
484 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
487 /// Returns the total amount paid on this [`Route`], excluding the fees.
489 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
490 /// we had to reach the [`htlc_minimum_msat`] limits.
492 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
493 pub fn get_total_amount(&self) -> u64 {
494 self.paths.iter().map(|path| path.final_value_msat()).sum()
498 impl fmt::Display for Route {
499 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
500 log_route!(self).fmt(f)
504 const SERIALIZATION_VERSION: u8 = 1;
505 const MIN_SERIALIZATION_VERSION: u8 = 1;
507 impl Writeable for Route {
508 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
509 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
510 (self.paths.len() as u64).write(writer)?;
511 let mut blinded_tails = Vec::new();
512 for path in self.paths.iter() {
513 (path.hops.len() as u8).write(writer)?;
514 for (idx, hop) in path.hops.iter().enumerate() {
516 if let Some(blinded_tail) = &path.blinded_tail {
517 if blinded_tails.is_empty() {
518 blinded_tails = Vec::with_capacity(path.hops.len());
520 blinded_tails.push(None);
523 blinded_tails.push(Some(blinded_tail));
524 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
527 write_tlv_fields!(writer, {
528 // For compatibility with LDK versions prior to 0.0.117, we take the individual
529 // RouteParameters' fields and reconstruct them on read.
530 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
531 (2, blinded_tails, optional_vec),
532 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
533 (5, self.route_params.as_ref().map(|p| p.max_total_routing_fee_msat), option),
539 impl Readable for Route {
540 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
541 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
542 let path_count: u64 = Readable::read(reader)?;
543 if path_count == 0 { return Err(DecodeError::InvalidValue); }
544 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
545 let mut min_final_cltv_expiry_delta = u32::max_value();
546 for _ in 0..path_count {
547 let hop_count: u8 = Readable::read(reader)?;
548 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
549 for _ in 0..hop_count {
550 hops.push(Readable::read(reader)?);
552 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
553 min_final_cltv_expiry_delta =
554 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
555 paths.push(Path { hops, blinded_tail: None });
557 _init_and_read_len_prefixed_tlv_fields!(reader, {
558 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
559 (2, blinded_tails, optional_vec),
560 (3, final_value_msat, option),
561 (5, max_total_routing_fee_msat, option)
563 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
564 if blinded_tails.len() != 0 {
565 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
566 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
567 path.blinded_tail = blinded_tail_opt;
571 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
572 let route_params = match (payment_params, final_value_msat) {
573 (Some(payment_params), Some(final_value_msat)) => {
574 Some(RouteParameters { payment_params, final_value_msat, max_total_routing_fee_msat })
579 Ok(Route { paths, route_params })
583 /// Parameters needed to find a [`Route`].
585 /// Passed to [`find_route`] and [`build_route_from_hops`].
586 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
587 pub struct RouteParameters {
588 /// The parameters of the failed payment path.
589 pub payment_params: PaymentParameters,
591 /// The amount in msats sent on the failed payment path.
592 pub final_value_msat: u64,
594 /// The maximum total fees, in millisatoshi, that may accrue during route finding.
596 /// This limit also applies to the total fees that may arise while retrying failed payment
599 /// Note that values below a few sats may result in some paths being spuriously ignored.
600 pub max_total_routing_fee_msat: Option<u64>,
603 impl RouteParameters {
604 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
606 /// [`Self::max_total_routing_fee_msat`] defaults to 1% of the payment amount + 50 sats
607 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
608 Self { payment_params, final_value_msat, max_total_routing_fee_msat: Some(final_value_msat / 100 + 50_000) }
612 impl Writeable for RouteParameters {
613 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
614 write_tlv_fields!(writer, {
615 (0, self.payment_params, required),
616 (1, self.max_total_routing_fee_msat, option),
617 (2, self.final_value_msat, required),
618 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
619 // `RouteParameters` directly. For compatibility, we write it here.
620 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
626 impl Readable for RouteParameters {
627 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
628 _init_and_read_len_prefixed_tlv_fields!(reader, {
629 (0, payment_params, (required: ReadableArgs, 0)),
630 (1, max_total_routing_fee_msat, option),
631 (2, final_value_msat, required),
632 (4, final_cltv_delta, option),
634 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
635 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
636 if final_cltv_expiry_delta == &0 {
637 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
642 final_value_msat: final_value_msat.0.unwrap(),
643 max_total_routing_fee_msat,
648 /// Maximum total CTLV difference we allow for a full payment path.
649 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
651 /// Maximum number of paths we allow an (MPP) payment to have.
652 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
653 // limits, but for now more than 10 paths likely carries too much one-path failure.
654 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
656 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
658 // The median hop CLTV expiry delta currently seen in the network.
659 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
661 // During routing, we only consider paths shorter than our maximum length estimate.
662 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
663 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
664 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
666 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
667 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
668 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
669 // (payment_secret and total_msat) = 93 bytes for the final hop.
670 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
671 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
672 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
674 /// Information used to route a payment.
675 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
676 pub struct PaymentParameters {
677 /// Information about the payee, such as their features and route hints for their channels.
680 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
681 pub expiry_time: Option<u64>,
683 /// The maximum total CLTV delta we accept for the route.
684 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
685 pub max_total_cltv_expiry_delta: u32,
687 /// The maximum number of paths that may be used by (MPP) payments.
688 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
689 pub max_path_count: u8,
691 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
692 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
693 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
694 /// increasing failure probability for those paths.
696 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
697 /// restriction have been found. While paths which meet this criteria will be searched for, it
698 /// is ultimately up to the scorer to select them over other paths.
700 /// A value of 0 will allow payments up to and including a channel's total announced usable
701 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
704 pub max_channel_saturation_power_of_half: u8,
706 /// A list of SCIDs which this payment was previously attempted over and which caused the
707 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
709 pub previously_failed_channels: Vec<u64>,
712 impl Writeable for PaymentParameters {
713 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
714 let mut clear_hints = &vec![];
715 let mut blinded_hints = &vec![];
717 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
718 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
720 write_tlv_fields!(writer, {
721 (0, self.payee.node_id(), option),
722 (1, self.max_total_cltv_expiry_delta, required),
723 (2, self.payee.features(), option),
724 (3, self.max_path_count, required),
725 (4, *clear_hints, required_vec),
726 (5, self.max_channel_saturation_power_of_half, required),
727 (6, self.expiry_time, option),
728 (7, self.previously_failed_channels, required_vec),
729 (8, *blinded_hints, optional_vec),
730 (9, self.payee.final_cltv_expiry_delta(), option),
736 impl ReadableArgs<u32> for PaymentParameters {
737 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
738 _init_and_read_len_prefixed_tlv_fields!(reader, {
739 (0, payee_pubkey, option),
740 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
741 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
742 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
743 (4, clear_route_hints, required_vec),
744 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
745 (6, expiry_time, option),
746 (7, previously_failed_channels, optional_vec),
747 (8, blinded_route_hints, optional_vec),
748 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
750 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
751 let payee = if blinded_route_hints.len() != 0 {
752 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
754 route_hints: blinded_route_hints,
755 features: features.and_then(|f: Features| f.bolt12()),
759 route_hints: clear_route_hints,
760 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
761 features: features.and_then(|f| f.bolt11()),
762 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
766 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
767 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
769 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
771 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
777 impl PaymentParameters {
778 /// Creates a payee with the node id of the given `pubkey`.
780 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
782 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
784 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
786 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
787 max_path_count: DEFAULT_MAX_PATH_COUNT,
788 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
789 previously_failed_channels: Vec::new(),
793 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
795 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
798 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
799 /// whether your router will be allowed to find a multi-part route for this payment. If you
800 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
801 /// [`RecipientOnionFields::secret_only`].
803 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
804 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
805 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
806 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
807 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
810 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
811 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
812 /// [`PaymentParameters::expiry_time`].
813 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
814 Self::blinded(invoice.payment_paths().to_vec())
815 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
816 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
819 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
820 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
822 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
824 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
825 max_path_count: DEFAULT_MAX_PATH_COUNT,
826 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
827 previously_failed_channels: Vec::new(),
831 /// Includes the payee's features. Errors if the parameters were not initialized with
832 /// [`PaymentParameters::from_bolt12_invoice`].
834 /// This is not exported to bindings users since bindings don't support move semantics
835 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
837 Payee::Clear { .. } => Err(()),
838 Payee::Blinded { route_hints, .. } =>
839 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
843 /// Includes the payee's features. Errors if the parameters were initialized with
844 /// [`PaymentParameters::from_bolt12_invoice`].
846 /// This is not exported to bindings users since bindings don't support move semantics
847 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
849 Payee::Blinded { .. } => Err(()),
850 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
852 payee: Payee::Clear {
853 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
859 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
860 /// [`PaymentParameters::from_bolt12_invoice`].
862 /// This is not exported to bindings users since bindings don't support move semantics
863 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
865 Payee::Blinded { .. } => Err(()),
866 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
868 payee: Payee::Clear {
869 route_hints, node_id, features, final_cltv_expiry_delta,
875 /// Includes a payment expiration in seconds relative to the UNIX epoch.
877 /// This is not exported to bindings users since bindings don't support move semantics
878 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
879 Self { expiry_time: Some(expiry_time), ..self }
882 /// Includes a limit for the total CLTV expiry delta which is considered during routing
884 /// This is not exported to bindings users since bindings don't support move semantics
885 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
886 Self { max_total_cltv_expiry_delta, ..self }
889 /// Includes a limit for the maximum number of payment paths that may be used.
891 /// This is not exported to bindings users since bindings don't support move semantics
892 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
893 Self { max_path_count, ..self }
896 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
897 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
899 /// This is not exported to bindings users since bindings don't support move semantics
900 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
901 Self { max_channel_saturation_power_of_half, ..self }
905 /// The recipient of a payment, differing based on whether they've hidden their identity with route
907 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
909 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
910 /// will be included in the final [`Route`].
912 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
914 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
915 /// Features supported by the payee.
917 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
919 features: Option<Bolt12InvoiceFeatures>,
921 /// The recipient included these route hints in their BOLT11 invoice.
923 /// The node id of the payee.
925 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
926 route_hints: Vec<RouteHint>,
927 /// Features supported by the payee.
929 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
930 /// does not contain any features.
932 /// [`for_keysend`]: PaymentParameters::for_keysend
933 features: Option<Bolt11InvoiceFeatures>,
934 /// The minimum CLTV delta at the end of the route. This value must not be zero.
935 final_cltv_expiry_delta: u32,
940 fn node_id(&self) -> Option<PublicKey> {
942 Self::Clear { node_id, .. } => Some(*node_id),
946 fn node_features(&self) -> Option<NodeFeatures> {
948 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
949 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
952 fn supports_basic_mpp(&self) -> bool {
954 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
955 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
958 fn features(&self) -> Option<FeaturesRef> {
960 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
961 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
964 fn final_cltv_expiry_delta(&self) -> Option<u32> {
966 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
970 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
972 Self::Blinded { route_hints, .. } => &route_hints[..],
973 Self::Clear { .. } => &[]
977 fn unblinded_route_hints(&self) -> &[RouteHint] {
979 Self::Blinded { .. } => &[],
980 Self::Clear { route_hints, .. } => &route_hints[..]
985 enum FeaturesRef<'a> {
986 Bolt11(&'a Bolt11InvoiceFeatures),
987 Bolt12(&'a Bolt12InvoiceFeatures),
990 Bolt11(Bolt11InvoiceFeatures),
991 Bolt12(Bolt12InvoiceFeatures),
995 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
997 Self::Bolt12(f) => Some(f),
1001 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
1003 Self::Bolt11(f) => Some(f),
1009 impl<'a> Writeable for FeaturesRef<'a> {
1010 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1012 Self::Bolt11(f) => Ok(f.write(w)?),
1013 Self::Bolt12(f) => Ok(f.write(w)?),
1018 impl ReadableArgs<bool> for Features {
1019 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
1020 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
1021 Ok(Self::Bolt12(Readable::read(reader)?))
1025 /// A list of hops along a payment path terminating with a channel to the recipient.
1026 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1027 pub struct RouteHint(pub Vec<RouteHintHop>);
1029 impl Writeable for RouteHint {
1030 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1031 (self.0.len() as u64).write(writer)?;
1032 for hop in self.0.iter() {
1039 impl Readable for RouteHint {
1040 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1041 let hop_count: u64 = Readable::read(reader)?;
1042 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
1043 for _ in 0..hop_count {
1044 hops.push(Readable::read(reader)?);
1050 /// A channel descriptor for a hop along a payment path.
1052 /// While this generally comes from BOLT 11's `r` field, this struct includes more fields than are
1053 /// available in BOLT 11. Thus, encoding and decoding this via `lightning-invoice` is lossy, as
1054 /// fields not supported in BOLT 11 will be stripped.
1055 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1056 pub struct RouteHintHop {
1057 /// The node_id of the non-target end of the route
1058 pub src_node_id: PublicKey,
1059 /// The short_channel_id of this channel
1060 pub short_channel_id: u64,
1061 /// The fees which must be paid to use this channel
1062 pub fees: RoutingFees,
1063 /// The difference in CLTV values between this node and the next node.
1064 pub cltv_expiry_delta: u16,
1065 /// The minimum value, in msat, which must be relayed to the next hop.
1066 pub htlc_minimum_msat: Option<u64>,
1067 /// The maximum value in msat available for routing with a single HTLC.
1068 pub htlc_maximum_msat: Option<u64>,
1071 impl_writeable_tlv_based!(RouteHintHop, {
1072 (0, src_node_id, required),
1073 (1, htlc_minimum_msat, option),
1074 (2, short_channel_id, required),
1075 (3, htlc_maximum_msat, option),
1076 (4, fees, required),
1077 (6, cltv_expiry_delta, required),
1080 #[derive(Eq, PartialEq)]
1081 #[repr(align(64))] // Force the size to 64 bytes
1082 struct RouteGraphNode {
1085 // The maximum value a yet-to-be-constructed payment path might flow through this node.
1086 // This value is upper-bounded by us by:
1087 // - how much is needed for a path being constructed
1088 // - how much value can channels following this node (up to the destination) can contribute,
1089 // considering their capacity and fees
1090 value_contribution_msat: u64,
1091 total_cltv_delta: u32,
1092 /// The number of hops walked up to this node.
1093 path_length_to_node: u8,
1096 impl cmp::Ord for RouteGraphNode {
1097 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
1098 other.score.cmp(&self.score).then_with(|| other.node_id.cmp(&self.node_id))
1102 impl cmp::PartialOrd for RouteGraphNode {
1103 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
1104 Some(self.cmp(other))
1108 // While RouteGraphNode can be laid out with fewer bytes, performance appears to be improved
1109 // substantially when it is laid out at exactly 64 bytes.
1111 // Thus, we use `#[repr(C)]` on the struct to force a suboptimal layout and check that it stays 64
1113 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1114 const _GRAPH_NODE_SMALL: usize = 64 - core::mem::size_of::<RouteGraphNode>();
1115 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1116 const _GRAPH_NODE_FIXED_SIZE: usize = core::mem::size_of::<RouteGraphNode>() - 64;
1118 /// A wrapper around the various hop representations.
1120 /// Can be used to examine the properties of a hop,
1121 /// potentially to decide whether to include it in a route.
1122 #[derive(Clone, Debug)]
1123 pub enum CandidateRouteHop<'a> {
1124 /// A hop from the payer, where the outbound liquidity is known.
1126 /// Channel details of the first hop
1128 /// [`ChannelDetails::get_outbound_payment_scid`] MUST be `Some` (indicating the channel
1129 /// has been funded and is able to pay), and accessor methods may panic otherwise.
1131 /// [`find_route`] validates this prior to constructing a [`CandidateRouteHop`].
1132 details: &'a ChannelDetails,
1133 /// The node id of the payer, which is also the source side of this candidate route hop.
1134 payer_node_id: &'a NodeId,
1136 /// A hop found in the [`ReadOnlyNetworkGraph`].
1138 /// Information about the channel, including potentially its capacity and
1139 /// direction-specific information.
1140 info: DirectedChannelInfo<'a>,
1141 /// The short channel ID of the channel, i.e. the identifier by which we refer to this
1143 short_channel_id: u64,
1145 /// A private hop communicated by the payee, generally via a BOLT 11 invoice.
1147 /// Because BOLT 11 route hints can take multiple hops to get to the destination, this may not
1148 /// terminate at the payee.
1150 /// Information about the private hop communicated via BOLT 11.
1151 hint: &'a RouteHintHop,
1152 /// Node id of the next hop in BOLT 11 route hint.
1153 target_node_id: &'a NodeId
1155 /// A blinded path which starts with an introduction point and ultimately terminates with the
1158 /// Because we don't know the payee's identity, [`CandidateRouteHop::target`] will return
1159 /// `None` in this state.
1161 /// Because blinded paths are "all or nothing", and we cannot use just one part of a blinded
1162 /// path, the full path is treated as a single [`CandidateRouteHop`].
1164 /// Information about the blinded path including the fee, HTLC amount limits, and
1165 /// cryptographic material required to build an HTLC through the given path.
1166 hint: &'a (BlindedPayInfo, BlindedPath),
1167 /// Index of the hint in the original list of blinded hints.
1169 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1170 /// a short channel ID for this hop.
1173 /// Similar to [`Self::Blinded`], but the path here only has one hop.
1175 /// While we treat this similarly to [`CandidateRouteHop::Blinded`] in many respects (e.g.
1176 /// returning `None` from [`CandidateRouteHop::target`]), in this case we do actually know the
1177 /// payee's identity - it's the introduction point!
1179 /// [`BlindedPayInfo`] provided for 1-hop blinded paths is ignored because it is meant to apply
1180 /// to the hops *between* the introduction node and the destination.
1182 /// This primarily exists to track that we need to included a blinded path at the end of our
1183 /// [`Route`], even though it doesn't actually add an additional hop in the payment.
1185 /// Information about the blinded path including the fee, HTLC amount limits, and
1186 /// cryptographic material required to build an HTLC terminating with the given path.
1188 /// Note that the [`BlindedPayInfo`] is ignored here.
1189 hint: &'a (BlindedPayInfo, BlindedPath),
1190 /// Index of the hint in the original list of blinded hints.
1192 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1193 /// a short channel ID for this hop.
1198 impl<'a> CandidateRouteHop<'a> {
1199 /// Returns the short channel ID for this hop, if one is known.
1201 /// This SCID could be an alias or a globally unique SCID, and thus is only expected to
1202 /// uniquely identify this channel in conjunction with the [`CandidateRouteHop::source`].
1204 /// Returns `Some` as long as the candidate is a [`CandidateRouteHop::PublicHop`], a
1205 /// [`CandidateRouteHop::PrivateHop`] from a BOLT 11 route hint, or a
1206 /// [`CandidateRouteHop::FirstHop`] with a known [`ChannelDetails::get_outbound_payment_scid`]
1207 /// (which is always true for channels which are funded and ready for use).
1209 /// In other words, this should always return `Some` as long as the candidate hop is not a
1210 /// [`CandidateRouteHop::Blinded`] or a [`CandidateRouteHop::OneHopBlinded`].
1212 /// Note that this is deliberately not public as it is somewhat of a footgun because it doesn't
1213 /// define a global namespace.
1215 fn short_channel_id(&self) -> Option<u64> {
1217 CandidateRouteHop::FirstHop { details, .. } => details.get_outbound_payment_scid(),
1218 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1219 CandidateRouteHop::PrivateHop { hint, .. } => Some(hint.short_channel_id),
1220 CandidateRouteHop::Blinded { .. } => None,
1221 CandidateRouteHop::OneHopBlinded { .. } => None,
1225 /// Returns the globally unique short channel ID for this hop, if one is known.
1227 /// This only returns `Some` if the channel is public (either our own, or one we've learned
1228 /// from the public network graph), and thus the short channel ID we have for this channel is
1229 /// globally unique and identifies this channel in a global namespace.
1231 pub fn globally_unique_short_channel_id(&self) -> Option<u64> {
1233 CandidateRouteHop::FirstHop { details, .. } => if details.is_public { details.short_channel_id } else { None },
1234 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1235 CandidateRouteHop::PrivateHop { .. } => None,
1236 CandidateRouteHop::Blinded { .. } => None,
1237 CandidateRouteHop::OneHopBlinded { .. } => None,
1241 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1242 fn features(&self) -> ChannelFeatures {
1244 CandidateRouteHop::FirstHop { details, .. } => details.counterparty.features.to_context(),
1245 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1246 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1247 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1248 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1252 /// Returns the required difference in HTLC CLTV expiry between the [`Self::source`] and the
1253 /// next-hop for an HTLC taking this hop.
1255 /// This is the time that the node(s) in this hop have to claim the HTLC on-chain if the
1256 /// next-hop goes on chain with a payment preimage.
1258 pub fn cltv_expiry_delta(&self) -> u32 {
1260 CandidateRouteHop::FirstHop { .. } => 0,
1261 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1262 CandidateRouteHop::PrivateHop { hint, .. } => hint.cltv_expiry_delta as u32,
1263 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1264 CandidateRouteHop::OneHopBlinded { .. } => 0,
1268 /// Returns the minimum amount that can be sent over this hop, in millisatoshis.
1270 pub fn htlc_minimum_msat(&self) -> u64 {
1272 CandidateRouteHop::FirstHop { details, .. } => details.next_outbound_htlc_minimum_msat,
1273 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1274 CandidateRouteHop::PrivateHop { hint, .. } => hint.htlc_minimum_msat.unwrap_or(0),
1275 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1276 CandidateRouteHop::OneHopBlinded { .. } => 0,
1280 /// Returns the fees that must be paid to route an HTLC over this channel.
1282 pub fn fees(&self) -> RoutingFees {
1284 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1285 base_msat: 0, proportional_millionths: 0,
1287 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1288 CandidateRouteHop::PrivateHop { hint, .. } => hint.fees,
1289 CandidateRouteHop::Blinded { hint, .. } => {
1291 base_msat: hint.0.fee_base_msat,
1292 proportional_millionths: hint.0.fee_proportional_millionths
1295 CandidateRouteHop::OneHopBlinded { .. } =>
1296 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1300 /// Fetch the effective capacity of this hop.
1302 /// Note that this may be somewhat expensive, so calls to this should be limited and results
1304 fn effective_capacity(&self) -> EffectiveCapacity {
1306 CandidateRouteHop::FirstHop { details, .. } => EffectiveCapacity::ExactLiquidity {
1307 liquidity_msat: details.next_outbound_htlc_limit_msat,
1309 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1310 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. } =>
1311 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1312 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. } =>
1313 EffectiveCapacity::Infinite,
1314 CandidateRouteHop::Blinded { hint, .. } =>
1315 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1316 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1320 /// Returns an ID describing the given hop.
1322 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1324 fn id(&self) -> CandidateHopId {
1326 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1327 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1328 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1331 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1333 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1339 /// Returns the source node id of current hop.
1341 /// Source node id refers to the node forwarding the HTLC through this hop.
1343 /// For [`Self::FirstHop`] we return payer's node id.
1345 pub fn source(&self) -> NodeId {
1347 CandidateRouteHop::FirstHop { payer_node_id, .. } => **payer_node_id,
1348 CandidateRouteHop::PublicHop { info, .. } => *info.source(),
1349 CandidateRouteHop::PrivateHop { hint, .. } => hint.src_node_id.into(),
1350 CandidateRouteHop::Blinded { hint, .. } => hint.1.introduction_node_id.into(),
1351 CandidateRouteHop::OneHopBlinded { hint, .. } => hint.1.introduction_node_id.into(),
1354 /// Returns the target node id of this hop, if known.
1356 /// Target node id refers to the node receiving the HTLC after this hop.
1358 /// For [`Self::Blinded`] we return `None` because the ultimate destination after the blinded
1359 /// path is unknown.
1361 /// For [`Self::OneHopBlinded`] we return `None` because the target is the same as the source,
1362 /// and such a return value would be somewhat nonsensical.
1364 pub fn target(&self) -> Option<NodeId> {
1366 CandidateRouteHop::FirstHop { details, .. } => Some(details.counterparty.node_id.into()),
1367 CandidateRouteHop::PublicHop { info, .. } => Some(*info.target()),
1368 CandidateRouteHop::PrivateHop { target_node_id, .. } => Some(**target_node_id),
1369 CandidateRouteHop::Blinded { .. } => None,
1370 CandidateRouteHop::OneHopBlinded { .. } => None,
1375 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1377 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1379 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1380 /// isn't guaranteed to be unique at all.
1382 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1383 /// difficult-to-use API.
1384 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1385 enum CandidateHopId {
1386 /// Contains (scid, src_node_id < target_node_id)
1388 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1393 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1394 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1396 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1397 EffectiveCapacity::Infinite => u64::max_value(),
1398 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1399 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1400 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1401 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1402 // expected to have been generated from up-to-date capacity information.
1403 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1404 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1405 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1409 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1410 -> bool where I1::Item: PartialEq<I2::Item> {
1412 let a = iter_a.next();
1413 let b = iter_b.next();
1414 if a.is_none() && b.is_none() { return true; }
1415 if a.is_none() || b.is_none() { return false; }
1416 if a.unwrap().ne(&b.unwrap()) { return false; }
1420 /// It's useful to keep track of the hops associated with the fees required to use them,
1421 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1422 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1423 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1425 #[repr(C)] // Force fields to appear in the order we define them.
1426 struct PathBuildingHop<'a> {
1427 candidate: CandidateRouteHop<'a>,
1428 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1429 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1430 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1431 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1432 /// avoid processing them again.
1433 was_processed: bool,
1434 /// Used to compare channels when choosing the for routing.
1435 /// Includes paying for the use of a hop and the following hops, as well as
1436 /// an estimated cost of reaching this hop.
1437 /// Might get stale when fees are recomputed. Primarily for internal use.
1438 total_fee_msat: u64,
1439 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1440 /// walk and may be invalid thereafter.
1441 path_htlc_minimum_msat: u64,
1442 /// All penalties incurred from this channel on the way to the destination, as calculated using
1443 /// channel scoring.
1444 path_penalty_msat: u64,
1446 // The last 16 bytes are on the next cache line by default in glibc's malloc. Thus, we should
1447 // only place fields which are not hot there. Luckily, the next three fields are only read if
1448 // we end up on the selected path, and only in the final path layout phase, so we don't care
1449 // too much if reading them is slow.
1453 /// All the fees paid *after* this channel on the way to the destination
1454 next_hops_fee_msat: u64,
1455 /// Fee paid for the use of the current channel (see candidate.fees()).
1456 /// The value will be actually deducted from the counterparty balance on the previous link.
1457 hop_use_fee_msat: u64,
1459 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1460 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1461 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1462 // value_contribution_msat, which requires tracking it here. See comments below where it is
1463 // used for more info.
1464 value_contribution_msat: u64,
1467 // Checks that the entries in the `find_route` `dist` map fit in (exactly) two standard x86-64
1468 // cache lines. Sadly, they're not guaranteed to actually lie on a cache line (and in fact,
1469 // generally won't, because at least glibc's malloc will align to a nice, big, round
1470 // boundary...plus 16), but at least it will reduce the amount of data we'll need to load.
1472 // Note that these assertions only pass on somewhat recent rustc, and thus are gated on the
1475 const _NODE_MAP_SIZE_TWO_CACHE_LINES: usize = 128 - core::mem::size_of::<(NodeId, PathBuildingHop)>();
1477 const _NODE_MAP_SIZE_EXACTLY_CACHE_LINES: usize = core::mem::size_of::<(NodeId, PathBuildingHop)>() - 128;
1479 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1480 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1481 let mut debug_struct = f.debug_struct("PathBuildingHop");
1483 .field("node_id", &self.candidate.target())
1484 .field("short_channel_id", &self.candidate.short_channel_id())
1485 .field("total_fee_msat", &self.total_fee_msat)
1486 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1487 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1488 .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)))
1489 .field("path_penalty_msat", &self.path_penalty_msat)
1490 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1491 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1492 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1493 let debug_struct = debug_struct
1494 .field("value_contribution_msat", &self.value_contribution_msat);
1495 debug_struct.finish()
1499 // Instantiated with a list of hops with correct data in them collected during path finding,
1500 // an instance of this struct should be further modified only via given methods.
1502 struct PaymentPath<'a> {
1503 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1506 impl<'a> PaymentPath<'a> {
1507 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1508 fn get_value_msat(&self) -> u64 {
1509 self.hops.last().unwrap().0.fee_msat
1512 fn get_path_penalty_msat(&self) -> u64 {
1513 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1516 fn get_total_fee_paid_msat(&self) -> u64 {
1517 if self.hops.len() < 1 {
1521 // Can't use next_hops_fee_msat because it gets outdated.
1522 for (i, (hop, _)) in self.hops.iter().enumerate() {
1523 if i != self.hops.len() - 1 {
1524 result += hop.fee_msat;
1530 fn get_cost_msat(&self) -> u64 {
1531 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1534 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1535 // to change fees may result in an inconsistency.
1537 // Sometimes we call this function right after constructing a path which is inconsistent in
1538 // that it the value being transferred has decreased while we were doing path finding, leading
1539 // to the fees being paid not lining up with the actual limits.
1541 // Note that this function is not aware of the available_liquidity limit, and thus does not
1542 // support increasing the value being transferred beyond what was selected during the initial
1545 // Returns the amount that this path contributes to the total payment value, which may be greater
1546 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1547 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1548 let mut extra_contribution_msat = 0;
1549 let mut total_fee_paid_msat = 0 as u64;
1550 for i in (0..self.hops.len()).rev() {
1551 let last_hop = i == self.hops.len() - 1;
1553 // For non-last-hop, this value will represent the fees paid on the current hop. It
1554 // will consist of the fees for the use of the next hop, and extra fees to match
1555 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1556 let mut cur_hop_fees_msat = 0;
1558 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1561 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1562 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1563 cur_hop.path_penalty_msat += extra_contribution_msat;
1564 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1565 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1566 // set it too high just to maliciously take more fees by exploiting this
1567 // match htlc_minimum_msat logic.
1568 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1569 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1570 // Note that there is a risk that *previous hops* (those closer to us, as we go
1571 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1573 // This might make us end up with a broken route, although this should be super-rare
1574 // in practice, both because of how healthy channels look like, and how we pick
1575 // channels in add_entry.
1576 // Also, this can't be exploited more heavily than *announce a free path and fail
1578 cur_hop_transferred_amount_msat += extra_fees_msat;
1580 // We remember and return the extra fees on the final hop to allow accounting for
1581 // them in the path's value contribution.
1583 extra_contribution_msat = extra_fees_msat;
1585 total_fee_paid_msat += extra_fees_msat;
1586 cur_hop_fees_msat += extra_fees_msat;
1591 // Final hop is a special case: it usually has just value_msat (by design), but also
1592 // it still could overpay for the htlc_minimum_msat.
1593 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1595 // Propagate updated fees for the use of the channels to one hop back, where they
1596 // will be actually paid (fee_msat). The last hop is handled above separately.
1597 cur_hop.fee_msat = cur_hop_fees_msat;
1600 // Fee for the use of the current hop which will be deducted on the previous hop.
1601 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1602 // this channel is free for us.
1604 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1605 cur_hop.hop_use_fee_msat = new_fee;
1606 total_fee_paid_msat += new_fee;
1608 // It should not be possible because this function is called only to reduce the
1609 // value. In that case, compute_fee was already called with the same fees for
1610 // larger amount and there was no overflow.
1615 value_msat + extra_contribution_msat
1620 /// Calculate the fees required to route the given amount over a channel with the given fees.
1621 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1622 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1623 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1627 /// Calculate the fees required to route the given amount over a channel with the given fees,
1628 /// saturating to [`u64::max_value`].
1629 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1630 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1631 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1632 .saturating_add(channel_fees.base_msat as u64)
1635 /// The default `features` we assume for a node in a route, when no `features` are known about that
1638 /// Default features are:
1639 /// * variable_length_onion_optional
1640 fn default_node_features() -> NodeFeatures {
1641 let mut features = NodeFeatures::empty();
1642 features.set_variable_length_onion_optional();
1646 struct LoggedPayeePubkey(Option<PublicKey>);
1647 impl fmt::Display for LoggedPayeePubkey {
1648 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1651 "payee node id ".fmt(f)?;
1655 "blinded payee".fmt(f)
1661 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1662 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1663 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1665 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1666 "blinded route hint with introduction node id ".fmt(f)?;
1667 hint.1.introduction_node_id.fmt(f)?;
1668 " and blinding point ".fmt(f)?;
1669 hint.1.blinding_point.fmt(f)
1671 CandidateRouteHop::FirstHop { .. } => {
1672 "first hop with SCID ".fmt(f)?;
1673 self.0.short_channel_id().unwrap().fmt(f)
1675 CandidateRouteHop::PrivateHop { .. } => {
1676 "route hint with SCID ".fmt(f)?;
1677 self.0.short_channel_id().unwrap().fmt(f)
1681 self.0.short_channel_id().unwrap().fmt(f)
1688 fn sort_first_hop_channels(
1689 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1690 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1692 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1693 // most like to use.
1695 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1696 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1699 // Second, because simply always sorting in descending order would always use our largest
1700 // available outbound capacity, needlessly fragmenting our available channel capacities,
1701 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1702 // which have enough, but not too much, capacity for the payment.
1704 // Available outbound balances factor in liquidity already reserved for previously found paths.
1705 channels.sort_unstable_by(|chan_a, chan_b| {
1706 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1707 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1708 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1709 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1710 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1711 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1712 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1713 // Sort in descending order
1714 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1716 // Sort in ascending order
1717 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1722 /// Finds a route from us (payer) to the given target node (payee).
1724 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1725 /// in the given [`RouteParameters::payment_params`].
1726 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1728 /// Private routing paths between a public node and the target may be included in the `payee` field
1729 /// of [`RouteParameters::payment_params`].
1731 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1732 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1733 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1735 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1736 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1737 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1741 /// Panics if first_hops contains channels without `short_channel_id`s;
1742 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1744 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1745 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1746 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1747 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1748 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1749 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1750 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1751 ) -> Result<Route, LightningError>
1752 where L::Target: Logger, GL::Target: Logger {
1753 let graph_lock = network_graph.read_only();
1754 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1755 scorer, score_params, random_seed_bytes)?;
1756 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1760 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1761 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1762 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1763 _random_seed_bytes: &[u8; 32]
1764 ) -> Result<Route, LightningError>
1765 where L::Target: Logger {
1767 let payment_params = &route_params.payment_params;
1768 let final_value_msat = route_params.final_value_msat;
1769 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1770 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1771 // so use a dummy id for this in the blinded case.
1772 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1773 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1774 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1775 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1776 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1778 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1779 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1781 if our_node_id == maybe_dummy_payee_node_id {
1782 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1785 if final_value_msat > MAX_VALUE_MSAT {
1786 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1789 if final_value_msat == 0 {
1790 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1793 match &payment_params.payee {
1794 Payee::Clear { route_hints, node_id, .. } => {
1795 for route in route_hints.iter() {
1796 for hop in &route.0 {
1797 if hop.src_node_id == *node_id {
1798 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1803 Payee::Blinded { route_hints, .. } => {
1804 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1805 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});
1807 for (_, blinded_path) in route_hints.iter() {
1808 if blinded_path.blinded_hops.len() == 0 {
1809 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1810 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1811 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1812 } else if blinded_path.blinded_hops.len() == 1 &&
1813 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1814 && p.introduction_node_id != blinded_path.introduction_node_id)
1816 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1821 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1822 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1823 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});
1826 // The general routing idea is the following:
1827 // 1. Fill first/last hops communicated by the caller.
1828 // 2. Attempt to construct a path from payer to payee for transferring
1829 // any ~sufficient (described later) value.
1830 // If succeed, remember which channels were used and how much liquidity they have available,
1831 // so that future paths don't rely on the same liquidity.
1832 // 3. Proceed to the next step if:
1833 // - we hit the recommended target value;
1834 // - OR if we could not construct a new path. Any next attempt will fail too.
1835 // Otherwise, repeat step 2.
1836 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1837 // (not recommended value).
1838 // 5. If yes, proceed. If not, fail routing.
1839 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1840 // transferred up to the transfer target value.
1841 // 7. Reduce the value of the last path until we are sending only the target value.
1842 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1843 // them so that we're not sending two HTLCs along the same path.
1845 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1846 // distance from the payee
1848 // We are not a faithful Dijkstra's implementation because we can change values which impact
1849 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1850 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1851 // the value we are currently attempting to send over a path, we simply reduce the value being
1852 // sent along the path for any hops after that channel. This may imply that later fees (which
1853 // we've already tabulated) are lower because a smaller value is passing through the channels
1854 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1855 // channels which were selected earlier (and which may still be used for other paths without a
1856 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1859 // One potentially problematic case for this algorithm would be if there are many
1860 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1861 // graph walking), we may never find a path which is not liquidity-limited and has lower
1862 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1863 // Because we only consider paths with at least 5% of the total value being sent, the damage
1864 // from such a case should be limited, however this could be further reduced in the future by
1865 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1866 // limits for the purposes of fee calculation.
1868 // Alternatively, we could store more detailed path information in the heap (targets, below)
1869 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1870 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1871 // and practically (as we would need to store dynamically-allocated path information in heap
1872 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1873 // results of such an algorithm would likely be biased towards lower-value paths.
1875 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1876 // outside of our current search value, running a path search more times to gather candidate
1877 // paths at different values. While this may be acceptable, further path searches may increase
1878 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1879 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1880 // the same time, remaining generic across different payment values.
1882 let network_channels = network_graph.channels();
1883 let network_nodes = network_graph.nodes();
1885 if payment_params.max_path_count == 0 {
1886 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1889 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1890 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1892 let allow_mpp = if payment_params.max_path_count == 1 {
1894 } else if payment_params.payee.supports_basic_mpp() {
1896 } else if let Some(payee) = payee_node_id_opt {
1897 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1898 |info| info.features.supports_basic_mpp()))
1901 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1903 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1904 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1905 if allow_mpp { "with" } else { "without" },
1906 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1907 max_total_routing_fee_msat);
1910 // Prepare the data we'll use for payee-to-payer search by
1911 // inserting first hops suggested by the caller as targets.
1912 // Our search will then attempt to reach them while traversing from the payee node.
1913 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1914 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1915 if let Some(hops) = first_hops {
1917 if chan.get_outbound_payment_scid().is_none() {
1918 panic!("first_hops should be filled in with usable channels, not pending ones");
1920 if chan.counterparty.node_id == *our_node_pubkey {
1921 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1924 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1925 .or_insert(Vec::new())
1928 if first_hop_targets.is_empty() {
1929 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1933 let mut private_hop_key_cache = HashMap::with_capacity(
1934 payment_params.payee.unblinded_route_hints().iter().map(|path| path.0.len()).sum()
1937 // Because we store references to private hop node_ids in `dist`, below, we need them to exist
1938 // (as `NodeId`, not `PublicKey`) for the lifetime of `dist`. Thus, we calculate all the keys
1939 // we'll need here and simply fetch them when routing.
1940 private_hop_key_cache.insert(maybe_dummy_payee_pk, NodeId::from_pubkey(&maybe_dummy_payee_pk));
1941 for route in payment_params.payee.unblinded_route_hints().iter() {
1942 for hop in route.0.iter() {
1943 private_hop_key_cache.insert(hop.src_node_id, NodeId::from_pubkey(&hop.src_node_id));
1947 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1948 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1949 // adding duplicate entries when we find a better path to a given node.
1950 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1952 // Map from node_id to information about the best current path to that node, including feerate
1954 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1956 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1957 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1958 // htlc_minimum with extra fees while still finding a cheaper path.
1959 let mut hit_minimum_limit;
1961 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1962 // We start with a path_value of the exact amount we want, and if that generates a route we may
1963 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1964 // amount we want in total across paths, selecting the best subset at the end.
1965 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1966 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1967 let mut path_value_msat = final_value_msat;
1969 // Routing Fragmentation Mitigation heuristic:
1971 // Routing fragmentation across many payment paths increases the overall routing
1972 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1973 // Taking too many smaller paths also increases the chance of payment failure.
1974 // Thus to avoid this effect, we require from our collected links to provide
1975 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1976 // This requirement is currently set to be 1/max_path_count of the payment
1977 // value to ensure we only ever return routes that do not violate this limit.
1978 let minimal_value_contribution_msat: u64 = if allow_mpp {
1979 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1984 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1985 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1986 // drop the requirement by setting this to 0.
1987 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1989 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1990 // determine if the channel can be used by additional MPP paths or to inform path finding
1991 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1992 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1994 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1995 HashMap::with_capacity(network_nodes.len());
1997 // Keeping track of how much value we already collected across other paths. Helps to decide
1998 // when we want to stop looking for new paths.
1999 let mut already_collected_value_msat = 0;
2001 for (_, channels) in first_hop_targets.iter_mut() {
2002 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
2006 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
2007 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
2009 // Remember how many candidates we ignored to allow for some logging afterwards.
2010 let mut num_ignored_value_contribution: u32 = 0;
2011 let mut num_ignored_path_length_limit: u32 = 0;
2012 let mut num_ignored_cltv_delta_limit: u32 = 0;
2013 let mut num_ignored_previously_failed: u32 = 0;
2014 let mut num_ignored_total_fee_limit: u32 = 0;
2015 let mut num_ignored_avoid_overpayment: u32 = 0;
2016 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
2018 macro_rules! add_entry {
2019 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
2020 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
2021 // since that value has to be transferred over this channel.
2022 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
2023 ( $candidate: expr, $next_hops_fee_msat: expr,
2024 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
2025 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
2026 // We "return" whether we updated the path at the end, and how much we can route via
2027 // this channel, via this:
2028 let mut hop_contribution_amt_msat = None;
2029 // Channels to self should not be used. This is more of belt-and-suspenders, because in
2030 // practice these cases should be caught earlier:
2031 // - for regular channels at channel announcement (TODO)
2032 // - for first and last hops early in get_route
2033 let src_node_id = $candidate.source();
2034 if Some(src_node_id) != $candidate.target() {
2035 let scid_opt = $candidate.short_channel_id();
2036 let effective_capacity = $candidate.effective_capacity();
2037 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
2039 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
2040 // It may be misleading because we might later choose to reduce the value transferred
2041 // over these channels, and the channel which was insufficient might become sufficient.
2042 // Worst case: we drop a good channel here because it can't cover the high following
2043 // fees caused by one expensive channel, but then this channel could have been used
2044 // if the amount being transferred over this path is lower.
2045 // We do this for now, but this is a subject for removal.
2046 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
2047 let used_liquidity_msat = used_liquidities
2048 .get(&$candidate.id())
2049 .map_or(0, |used_liquidity_msat| {
2050 available_value_contribution_msat = available_value_contribution_msat
2051 .saturating_sub(*used_liquidity_msat);
2052 *used_liquidity_msat
2055 // Verify the liquidity offered by this channel complies to the minimal contribution.
2056 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
2057 // Do not consider candidate hops that would exceed the maximum path length.
2058 let path_length_to_node = $next_hops_path_length + 1;
2059 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
2061 // Do not consider candidates that exceed the maximum total cltv expiry limit.
2062 // In order to already account for some of the privacy enhancing random CLTV
2063 // expiry delta offset we add on top later, we subtract a rough estimate
2064 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
2065 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
2066 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
2067 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
2068 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
2069 .saturating_add($candidate.cltv_expiry_delta());
2070 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
2072 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
2073 // Includes paying fees for the use of the following channels.
2074 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
2075 Some(result) => result,
2076 // Can't overflow due to how the values were computed right above.
2077 None => unreachable!(),
2079 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2080 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
2081 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
2083 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2084 let may_overpay_to_meet_path_minimum_msat =
2085 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
2086 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
2087 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
2088 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
2090 let payment_failed_on_this_channel = scid_opt.map_or(false,
2091 |scid| payment_params.previously_failed_channels.contains(&scid));
2093 let (should_log_candidate, first_hop_details) = match $candidate {
2094 CandidateRouteHop::FirstHop { details, .. } => (true, Some(details)),
2095 CandidateRouteHop::PrivateHop { .. } => (true, None),
2096 CandidateRouteHop::Blinded { .. } => (true, None),
2097 CandidateRouteHop::OneHopBlinded { .. } => (true, None),
2101 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
2102 // bother considering this channel. If retrying with recommended_value_msat may
2103 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
2104 // around again with a higher amount.
2105 if !contributes_sufficient_value {
2106 if should_log_candidate {
2107 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
2109 if let Some(details) = first_hop_details {
2111 "First hop candidate next_outbound_htlc_limit_msat: {}",
2112 details.next_outbound_htlc_limit_msat,
2116 num_ignored_value_contribution += 1;
2117 } else if exceeds_max_path_length {
2118 if should_log_candidate {
2119 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
2121 num_ignored_path_length_limit += 1;
2122 } else if exceeds_cltv_delta_limit {
2123 if should_log_candidate {
2124 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
2126 if let Some(_) = first_hop_details {
2128 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
2129 hop_total_cltv_delta,
2130 max_total_cltv_expiry_delta,
2134 num_ignored_cltv_delta_limit += 1;
2135 } else if payment_failed_on_this_channel {
2136 if should_log_candidate {
2137 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
2139 num_ignored_previously_failed += 1;
2140 } else if may_overpay_to_meet_path_minimum_msat {
2141 if should_log_candidate {
2143 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
2144 LoggedCandidateHop(&$candidate));
2146 if let Some(details) = first_hop_details {
2148 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2149 details.next_outbound_htlc_minimum_msat,
2153 num_ignored_avoid_overpayment += 1;
2154 hit_minimum_limit = true;
2155 } else if over_path_minimum_msat {
2156 // Note that low contribution here (limited by available_liquidity_msat)
2157 // might violate htlc_minimum_msat on the hops which are next along the
2158 // payment path (upstream to the payee). To avoid that, we recompute
2159 // path fees knowing the final path contribution after constructing it.
2160 let curr_min = cmp::max(
2161 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2163 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2164 .saturating_add(curr_min);
2165 let hm_entry = dist.entry(src_node_id);
2166 let old_entry = hm_entry.or_insert_with(|| {
2167 // If there was previously no known way to access the source node
2168 // (recall it goes payee-to-payer) of short_channel_id, first add a
2169 // semi-dummy record just to compute the fees to reach the source node.
2170 // This will affect our decision on selecting short_channel_id
2171 // as a way to reach the $candidate.target() node.
2173 candidate: $candidate.clone(),
2175 next_hops_fee_msat: u64::max_value(),
2176 hop_use_fee_msat: u64::max_value(),
2177 total_fee_msat: u64::max_value(),
2178 path_htlc_minimum_msat,
2179 path_penalty_msat: u64::max_value(),
2180 was_processed: false,
2181 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2182 value_contribution_msat,
2186 #[allow(unused_mut)] // We only use the mut in cfg(test)
2187 let mut should_process = !old_entry.was_processed;
2188 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2190 // In test/fuzzing builds, we do extra checks to make sure the skipping
2191 // of already-seen nodes only happens in cases we expect (see below).
2192 if !should_process { should_process = true; }
2196 let mut hop_use_fee_msat = 0;
2197 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2199 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2200 // will have the same effective-fee
2201 if src_node_id != our_node_id {
2202 // Note that `u64::max_value` means we'll always fail the
2203 // `old_entry.total_fee_msat > total_fee_msat` check below
2204 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2205 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2208 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2209 if total_fee_msat > max_total_routing_fee_msat {
2210 if should_log_candidate {
2211 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2213 if let Some(_) = first_hop_details {
2215 "First hop candidate routing fee: {}. Limit: {}",
2217 max_total_routing_fee_msat,
2221 num_ignored_total_fee_limit += 1;
2223 let channel_usage = ChannelUsage {
2224 amount_msat: amount_to_transfer_over_msat,
2225 inflight_htlc_msat: used_liquidity_msat,
2228 let channel_penalty_msat =
2229 scorer.channel_penalty_msat($candidate,
2232 let path_penalty_msat = $next_hops_path_penalty_msat
2233 .saturating_add(channel_penalty_msat);
2235 // Update the way of reaching $candidate.source()
2236 // with the given short_channel_id (from $candidate.target()),
2237 // if this way is cheaper than the already known
2238 // (considering the cost to "reach" this channel from the route destination,
2239 // the cost of using this channel,
2240 // and the cost of routing to the source node of this channel).
2241 // Also, consider that htlc_minimum_msat_difference, because we might end up
2242 // paying it. Consider the following exploit:
2243 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2244 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2245 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2246 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2248 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2249 // but it may require additional tracking - we don't want to double-count
2250 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2251 // can't use something that may decrease on future hops.
2252 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2253 .saturating_add(old_entry.path_penalty_msat);
2254 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2255 .saturating_add(path_penalty_msat);
2257 if !old_entry.was_processed && new_cost < old_cost {
2258 let new_graph_node = RouteGraphNode {
2259 node_id: src_node_id,
2260 score: cmp::max(total_fee_msat, path_htlc_minimum_msat).saturating_add(path_penalty_msat),
2261 total_cltv_delta: hop_total_cltv_delta,
2262 value_contribution_msat,
2263 path_length_to_node,
2265 targets.push(new_graph_node);
2266 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2267 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2268 old_entry.total_fee_msat = total_fee_msat;
2269 old_entry.candidate = $candidate.clone();
2270 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2271 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2272 old_entry.path_penalty_msat = path_penalty_msat;
2273 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2275 old_entry.value_contribution_msat = value_contribution_msat;
2277 hop_contribution_amt_msat = Some(value_contribution_msat);
2278 } else if old_entry.was_processed && new_cost < old_cost {
2279 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2281 // If we're skipping processing a node which was previously
2282 // processed even though we found another path to it with a
2283 // cheaper fee, check that it was because the second path we
2284 // found (which we are processing now) has a lower value
2285 // contribution due to an HTLC minimum limit.
2287 // e.g. take a graph with two paths from node 1 to node 2, one
2288 // through channel A, and one through channel B. Channel A and
2289 // B are both in the to-process heap, with their scores set by
2290 // a higher htlc_minimum than fee.
2291 // Channel A is processed first, and the channels onwards from
2292 // node 1 are added to the to-process heap. Thereafter, we pop
2293 // Channel B off of the heap, note that it has a much more
2294 // restrictive htlc_maximum_msat, and recalculate the fees for
2295 // all of node 1's channels using the new, reduced, amount.
2297 // This would be bogus - we'd be selecting a higher-fee path
2298 // with a lower htlc_maximum_msat instead of the one we'd
2299 // already decided to use.
2300 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2302 value_contribution_msat + path_penalty_msat <
2303 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2310 if should_log_candidate {
2312 "Ignoring {} due to its htlc_minimum_msat limit.",
2313 LoggedCandidateHop(&$candidate));
2315 if let Some(details) = first_hop_details {
2317 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2318 details.next_outbound_htlc_minimum_msat,
2322 num_ignored_htlc_minimum_msat_limit += 1;
2326 hop_contribution_amt_msat
2330 let default_node_features = default_node_features();
2332 // Find ways (channels with destination) to reach a given node and store them
2333 // in the corresponding data structures (routing graph etc).
2334 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2335 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2336 // This data can later be helpful to optimize routing (pay lower fees).
2337 macro_rules! add_entries_to_cheapest_to_target_node {
2338 ( $node: expr, $node_id: expr, $next_hops_value_contribution: expr,
2339 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2340 let fee_to_target_msat;
2341 let next_hops_path_htlc_minimum_msat;
2342 let next_hops_path_penalty_msat;
2343 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2344 let was_processed = elem.was_processed;
2345 elem.was_processed = true;
2346 fee_to_target_msat = elem.total_fee_msat;
2347 next_hops_path_htlc_minimum_msat = elem.path_htlc_minimum_msat;
2348 next_hops_path_penalty_msat = elem.path_penalty_msat;
2351 // Entries are added to dist in add_entry!() when there is a channel from a node.
2352 // Because there are no channels from payee, it will not have a dist entry at this point.
2353 // If we're processing any other node, it is always be the result of a channel from it.
2354 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2355 fee_to_target_msat = 0;
2356 next_hops_path_htlc_minimum_msat = 0;
2357 next_hops_path_penalty_msat = 0;
2362 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2363 for details in first_channels {
2364 let candidate = CandidateRouteHop::FirstHop {
2365 details, payer_node_id: &our_node_id,
2367 add_entry!(&candidate, fee_to_target_msat,
2368 $next_hops_value_contribution,
2369 next_hops_path_htlc_minimum_msat, next_hops_path_penalty_msat,
2370 $next_hops_cltv_delta, $next_hops_path_length);
2374 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2377 &default_node_features
2380 if !features.requires_unknown_bits() {
2381 for chan_id in $node.channels.iter() {
2382 let chan = network_channels.get(chan_id).unwrap();
2383 if !chan.features.requires_unknown_bits() {
2384 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2385 if first_hops.is_none() || *source != our_node_id {
2386 if directed_channel.direction().enabled {
2387 let candidate = CandidateRouteHop::PublicHop {
2388 info: directed_channel,
2389 short_channel_id: *chan_id,
2391 add_entry!(&candidate,
2393 $next_hops_value_contribution,
2394 next_hops_path_htlc_minimum_msat,
2395 next_hops_path_penalty_msat,
2396 $next_hops_cltv_delta, $next_hops_path_length);
2407 let mut payment_paths = Vec::<PaymentPath>::new();
2409 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2410 'paths_collection: loop {
2411 // For every new path, start from scratch, except for used_liquidities, which
2412 // helps to avoid reusing previously selected paths in future iterations.
2415 hit_minimum_limit = false;
2417 // If first hop is a private channel and the only way to reach the payee, this is the only
2418 // place where it could be added.
2419 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2420 for details in first_channels {
2421 let candidate = CandidateRouteHop::FirstHop {
2422 details, payer_node_id: &our_node_id,
2424 let added = add_entry!(&candidate, 0, path_value_msat,
2425 0, 0u64, 0, 0).is_some();
2426 log_trace!(logger, "{} direct route to payee via {}",
2427 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2431 // Add the payee as a target, so that the payee-to-payer
2432 // search algorithm knows what to start with.
2433 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2434 // The payee is not in our network graph, so nothing to add here.
2435 // There is still a chance of reaching them via last_hops though,
2436 // so don't yet fail the payment here.
2437 // If not, targets.pop() will not even let us enter the loop in step 2.
2440 add_entries_to_cheapest_to_target_node!(node, payee, path_value_msat, 0, 0);
2445 // If a caller provided us with last hops, add them to routing targets. Since this happens
2446 // earlier than general path finding, they will be somewhat prioritized, although currently
2447 // it matters only if the fees are exactly the same.
2448 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2449 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2450 let have_intro_node_in_graph =
2451 // Only add the hops in this route to our candidate set if either
2452 // we have a direct channel to the first hop or the first hop is
2453 // in the regular network graph.
2454 first_hop_targets.get(&intro_node_id).is_some() ||
2455 network_nodes.get(&intro_node_id).is_some();
2456 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2457 let candidate = if hint.1.blinded_hops.len() == 1 {
2458 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2459 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2460 let mut path_contribution_msat = path_value_msat;
2461 if let Some(hop_used_msat) = add_entry!(&candidate,
2462 0, path_contribution_msat, 0, 0_u64, 0, 0)
2464 path_contribution_msat = hop_used_msat;
2466 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2467 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2469 for details in first_channels {
2470 let first_hop_candidate = CandidateRouteHop::FirstHop {
2471 details, payer_node_id: &our_node_id,
2473 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2477 let path_min = candidate.htlc_minimum_msat().saturating_add(
2478 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2479 add_entry!(&first_hop_candidate, blinded_path_fee,
2480 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2481 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2485 for route in payment_params.payee.unblinded_route_hints().iter()
2486 .filter(|route| !route.0.is_empty())
2488 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2489 let first_hop_src_is_reachable =
2490 // Only add the hops in this route to our candidate set if either we are part of
2491 // the first hop, we have a direct channel to the first hop, or the first hop is in
2492 // the regular network graph.
2493 our_node_id == first_hop_src_id ||
2494 first_hop_targets.get(&first_hop_src_id).is_some() ||
2495 network_nodes.get(&first_hop_src_id).is_some();
2496 if first_hop_src_is_reachable {
2497 // We start building the path from reverse, i.e., from payee
2498 // to the first RouteHintHop in the path.
2499 let hop_iter = route.0.iter().rev();
2500 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2501 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2502 let mut hop_used = true;
2503 let mut aggregate_next_hops_fee_msat: u64 = 0;
2504 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2505 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2506 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2507 let mut aggregate_next_hops_path_length: u8 = 0;
2508 let mut aggregate_path_contribution_msat = path_value_msat;
2510 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2511 let target = private_hop_key_cache.get(&prev_hop_id).unwrap();
2513 if let Some(first_channels) = first_hop_targets.get(&target) {
2514 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2515 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2516 hop.short_channel_id);
2521 let candidate = network_channels
2522 .get(&hop.short_channel_id)
2523 .and_then(|channel| channel.as_directed_to(&target))
2524 .map(|(info, _)| CandidateRouteHop::PublicHop {
2526 short_channel_id: hop.short_channel_id,
2528 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop, target_node_id: target });
2530 if let Some(hop_used_msat) = add_entry!(&candidate,
2531 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2532 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2533 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2535 aggregate_path_contribution_msat = hop_used_msat;
2537 // If this hop was not used then there is no use checking the preceding
2538 // hops in the RouteHint. We can break by just searching for a direct
2539 // channel between last checked hop and first_hop_targets.
2543 let used_liquidity_msat = used_liquidities
2544 .get(&candidate.id()).copied()
2546 let channel_usage = ChannelUsage {
2547 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2548 inflight_htlc_msat: used_liquidity_msat,
2549 effective_capacity: candidate.effective_capacity(),
2551 let channel_penalty_msat = scorer.channel_penalty_msat(
2552 &candidate, channel_usage, score_params
2554 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2555 .saturating_add(channel_penalty_msat);
2557 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2558 .saturating_add(hop.cltv_expiry_delta as u32);
2560 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2563 // Searching for a direct channel between last checked hop and first_hop_targets
2564 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2565 sort_first_hop_channels(first_channels, &used_liquidities,
2566 recommended_value_msat, our_node_pubkey);
2567 for details in first_channels {
2568 let first_hop_candidate = CandidateRouteHop::FirstHop {
2569 details, payer_node_id: &our_node_id,
2571 add_entry!(&first_hop_candidate,
2572 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2573 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2574 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2582 // In the next values of the iterator, the aggregate fees already reflects
2583 // the sum of value sent from payer (final_value_msat) and routing fees
2584 // for the last node in the RouteHint. We need to just add the fees to
2585 // route through the current node so that the preceding node (next iteration)
2587 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2588 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2589 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2591 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2592 // this route hint's source node to forward said min over this channel.
2593 aggregate_next_hops_path_htlc_minimum_msat = {
2594 let curr_htlc_min = cmp::max(
2595 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2597 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2598 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2601 if idx == route.0.len() - 1 {
2602 // The last hop in this iterator is the first hop in
2603 // overall RouteHint.
2604 // If this hop connects to a node with which we have a direct channel,
2605 // ignore the network graph and, if the last hop was added, add our
2606 // direct channel to the candidate set.
2608 // Note that we *must* check if the last hop was added as `add_entry`
2609 // always assumes that the third argument is a node to which we have a
2611 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2612 sort_first_hop_channels(first_channels, &used_liquidities,
2613 recommended_value_msat, our_node_pubkey);
2614 for details in first_channels {
2615 let first_hop_candidate = CandidateRouteHop::FirstHop {
2616 details, payer_node_id: &our_node_id,
2618 add_entry!(&first_hop_candidate,
2619 aggregate_next_hops_fee_msat,
2620 aggregate_path_contribution_msat,
2621 aggregate_next_hops_path_htlc_minimum_msat,
2622 aggregate_next_hops_path_penalty_msat,
2623 aggregate_next_hops_cltv_delta,
2624 aggregate_next_hops_path_length);
2632 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2634 // At this point, targets are filled with the data from first and
2635 // last hops communicated by the caller, and the payment receiver.
2636 let mut found_new_path = false;
2639 // If this loop terminates due the exhaustion of targets, two situations are possible:
2640 // - not enough outgoing liquidity:
2641 // 0 < already_collected_value_msat < final_value_msat
2642 // - enough outgoing liquidity:
2643 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2644 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2645 // paths_collection will be stopped because found_new_path==false.
2646 // This is not necessarily a routing failure.
2647 'path_construction: while let Some(RouteGraphNode { node_id, total_cltv_delta, mut value_contribution_msat, path_length_to_node, .. }) = targets.pop() {
2649 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2650 // traversing the graph and arrange the path out of what we found.
2651 if node_id == our_node_id {
2652 let mut new_entry = dist.remove(&our_node_id).unwrap();
2653 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2656 let mut features_set = false;
2657 let target = ordered_hops.last().unwrap().0.candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2658 if let Some(first_channels) = first_hop_targets.get(&target) {
2659 for details in first_channels {
2660 if let CandidateRouteHop::FirstHop { details: last_hop_details, .. }
2661 = ordered_hops.last().unwrap().0.candidate
2663 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2664 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2665 features_set = true;
2672 if let Some(node) = network_nodes.get(&target) {
2673 if let Some(node_info) = node.announcement_info.as_ref() {
2674 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2676 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2679 // We can fill in features for everything except hops which were
2680 // provided via the invoice we're paying. We could guess based on the
2681 // recipient's features but for now we simply avoid guessing at all.
2685 // Means we succesfully traversed from the payer to the payee, now
2686 // save this path for the payment route. Also, update the liquidity
2687 // remaining on the used hops, so that we take them into account
2688 // while looking for more paths.
2689 if target == maybe_dummy_payee_node_id {
2693 new_entry = match dist.remove(&target) {
2694 Some(payment_hop) => payment_hop,
2695 // We can't arrive at None because, if we ever add an entry to targets,
2696 // we also fill in the entry in dist (see add_entry!).
2697 None => unreachable!(),
2699 // We "propagate" the fees one hop backward (topologically) here,
2700 // so that fees paid for a HTLC forwarding on the current channel are
2701 // associated with the previous channel (where they will be subtracted).
2702 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2703 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2705 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2706 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2708 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2709 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2711 let mut payment_path = PaymentPath {hops: ordered_hops};
2713 // We could have possibly constructed a slightly inconsistent path: since we reduce
2714 // value being transferred along the way, we could have violated htlc_minimum_msat
2715 // on some channels we already passed (assuming dest->source direction). Here, we
2716 // recompute the fees again, so that if that's the case, we match the currently
2717 // underpaid htlc_minimum_msat with fees.
2718 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2719 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2720 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2722 // Since a path allows to transfer as much value as
2723 // the smallest channel it has ("bottleneck"), we should recompute
2724 // the fees so sender HTLC don't overpay fees when traversing
2725 // larger channels than the bottleneck. This may happen because
2726 // when we were selecting those channels we were not aware how much value
2727 // this path will transfer, and the relative fee for them
2728 // might have been computed considering a larger value.
2729 // Remember that we used these channels so that we don't rely
2730 // on the same liquidity in future paths.
2731 let mut prevented_redundant_path_selection = false;
2732 for (hop, _) in payment_path.hops.iter() {
2733 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2734 let used_liquidity_msat = used_liquidities
2735 .entry(hop.candidate.id())
2736 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2737 .or_insert(spent_on_hop_msat);
2738 let hop_capacity = hop.candidate.effective_capacity();
2739 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2740 if *used_liquidity_msat == hop_max_msat {
2741 // If this path used all of this channel's available liquidity, we know
2742 // this path will not be selected again in the next loop iteration.
2743 prevented_redundant_path_selection = true;
2745 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2747 if !prevented_redundant_path_selection {
2748 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2749 // we'll probably end up picking the same path again on the next iteration.
2750 // Decrease the available liquidity of a hop in the middle of the path.
2751 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2752 let exhausted = u64::max_value();
2754 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2755 LoggedCandidateHop(victim_candidate));
2756 if let Some(scid) = victim_candidate.short_channel_id() {
2757 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2758 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2762 // Track the total amount all our collected paths allow to send so that we know
2763 // when to stop looking for more paths
2764 already_collected_value_msat += value_contribution_msat;
2766 payment_paths.push(payment_path);
2767 found_new_path = true;
2768 break 'path_construction;
2771 // If we found a path back to the payee, we shouldn't try to process it again. This is
2772 // the equivalent of the `elem.was_processed` check in
2773 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2774 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2776 // Otherwise, since the current target node is not us,
2777 // keep "unrolling" the payment graph from payee to payer by
2778 // finding a way to reach the current target from the payer side.
2779 match network_nodes.get(&node_id) {
2782 add_entries_to_cheapest_to_target_node!(node, node_id,
2783 value_contribution_msat,
2784 total_cltv_delta, path_length_to_node);
2790 if !found_new_path && channel_saturation_pow_half != 0 {
2791 channel_saturation_pow_half = 0;
2792 continue 'paths_collection;
2794 // If we don't support MPP, no use trying to gather more value ever.
2795 break 'paths_collection;
2799 // Stop either when the recommended value is reached or if no new path was found in this
2801 // In the latter case, making another path finding attempt won't help,
2802 // because we deterministically terminated the search due to low liquidity.
2803 if !found_new_path && channel_saturation_pow_half != 0 {
2804 channel_saturation_pow_half = 0;
2805 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2806 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2807 path_value_msat = recommended_value_msat;
2808 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2809 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2810 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2811 break 'paths_collection;
2812 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2813 // Further, if this was our first walk of the graph, and we weren't limited by an
2814 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2815 // limited by an htlc_minimum_msat value, find another path with a higher value,
2816 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2817 // still keeping a lower total fee than this path.
2818 if !hit_minimum_limit {
2819 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2820 break 'paths_collection;
2822 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.");
2823 path_value_msat = recommended_value_msat;
2827 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2828 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2829 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2830 num_ignored_total_fee_limit;
2831 if num_ignored_total > 0 {
2833 "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.",
2834 num_ignored_value_contribution, num_ignored_path_length_limit,
2835 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2836 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2837 num_ignored_total_fee_limit, num_ignored_total);
2841 if payment_paths.len() == 0 {
2842 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2845 if already_collected_value_msat < final_value_msat {
2846 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2850 let mut selected_route = payment_paths;
2852 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2853 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2855 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2856 // the value they contribute towards the payment amount.
2857 // We sort in descending order as we will remove from the front in `retain`, next.
2858 selected_route.sort_unstable_by(|a, b|
2859 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2860 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2863 // We should make sure that at least 1 path left.
2864 let mut paths_left = selected_route.len();
2865 selected_route.retain(|path| {
2866 if paths_left == 1 {
2869 let path_value_msat = path.get_value_msat();
2870 if path_value_msat <= overpaid_value_msat {
2871 overpaid_value_msat -= path_value_msat;
2877 debug_assert!(selected_route.len() > 0);
2879 if overpaid_value_msat != 0 {
2881 // Now, subtract the remaining overpaid value from the most-expensive path.
2882 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2883 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2884 selected_route.sort_unstable_by(|a, b| {
2885 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2886 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2887 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2889 let expensive_payment_path = selected_route.first_mut().unwrap();
2891 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2892 // can't go negative.
2893 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2894 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2898 // Sort by the path itself and combine redundant paths.
2899 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2900 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2902 selected_route.sort_unstable_by_key(|path| {
2903 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2904 debug_assert!(path.hops.len() <= key.len());
2905 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
2910 for idx in 0..(selected_route.len() - 1) {
2911 if idx + 1 >= selected_route.len() { break; }
2912 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
2913 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
2914 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2915 selected_route[idx].update_value_and_recompute_fees(new_value);
2916 selected_route.remove(idx + 1);
2920 let mut paths = Vec::new();
2921 for payment_path in selected_route {
2922 let mut hops = Vec::with_capacity(payment_path.hops.len());
2923 for (hop, node_features) in payment_path.hops.iter()
2924 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2926 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
2927 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2928 // If we sourced the hop from the graph we're sure the target node is announced.
2930 } else if let CandidateRouteHop::FirstHop { details, .. } = hop.candidate {
2931 // If this is a first hop we also know if it's announced.
2934 // If we sourced it any other way, we double-check the network graph to see if
2935 // there are announced channels between the endpoints. If so, the hop might be
2936 // referring to any of the announced channels, as its `short_channel_id` might be
2937 // an alias, in which case we don't take any chances here.
2938 network_graph.node(&target).map_or(false, |hop_node|
2939 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2940 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
2944 hops.push(RouteHop {
2945 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2946 node_features: node_features.clone(),
2947 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2948 channel_features: hop.candidate.features(),
2949 fee_msat: hop.fee_msat,
2950 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2951 maybe_announced_channel,
2954 let mut final_cltv_delta = final_cltv_expiry_delta;
2955 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2956 if let Some(blinded_path) = h.candidate.blinded_path() {
2957 final_cltv_delta = h.candidate.cltv_expiry_delta();
2959 hops: blinded_path.blinded_hops.clone(),
2960 blinding_point: blinded_path.blinding_point,
2961 excess_final_cltv_expiry_delta: 0,
2962 final_value_msat: h.fee_msat,
2966 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2967 // applicable for the previous hop.
2968 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2969 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2972 paths.push(Path { hops, blinded_tail });
2974 // Make sure we would never create a route with more paths than we allow.
2975 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2977 if let Some(node_features) = payment_params.payee.node_features() {
2978 for path in paths.iter_mut() {
2979 path.hops.last_mut().unwrap().node_features = node_features.clone();
2983 let route = Route { paths, route_params: Some(route_params.clone()) };
2985 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2986 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2987 if route.get_total_fees() > max_total_routing_fee_msat {
2988 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2989 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2993 log_info!(logger, "Got route: {}", log_route!(route));
2997 // When an adversarial intermediary node observes a payment, it may be able to infer its
2998 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2999 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
3000 // payment path by adding a randomized 'shadow route' offset to the final hop.
3001 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
3002 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
3004 let network_channels = network_graph.channels();
3005 let network_nodes = network_graph.nodes();
3007 for path in route.paths.iter_mut() {
3008 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
3010 // Remember the last three nodes of the random walk and avoid looping back on them.
3011 // Init with the last three nodes from the actual path, if possible.
3012 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
3013 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
3014 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
3016 // Choose the last publicly known node as the starting point for the random walk.
3017 let mut cur_hop: Option<NodeId> = None;
3018 let mut path_nonce = [0u8; 12];
3019 if let Some(starting_hop) = path.hops.iter().rev()
3020 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
3021 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
3022 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
3025 // Init PRNG with the path-dependant nonce, which is static for private paths.
3026 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
3027 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
3029 // Pick a random path length in [1 .. 3]
3030 prng.process_in_place(&mut random_path_bytes);
3031 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
3033 for random_hop in 0..random_walk_length {
3034 // If we don't find a suitable offset in the public network graph, we default to
3035 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3036 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
3038 if let Some(cur_node_id) = cur_hop {
3039 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
3040 // Randomly choose the next unvisited hop.
3041 prng.process_in_place(&mut random_path_bytes);
3042 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
3043 .checked_rem(cur_node.channels.len())
3044 .and_then(|index| cur_node.channels.get(index))
3045 .and_then(|id| network_channels.get(id)) {
3046 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
3047 if !nodes_to_avoid.iter().any(|x| x == next_id) {
3048 nodes_to_avoid[random_hop] = *next_id;
3049 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
3050 cur_hop = Some(*next_id);
3057 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
3058 .checked_add(random_hop_offset)
3059 .unwrap_or(shadow_ctlv_expiry_delta_offset);
3062 // Limit the total offset to reduce the worst-case locked liquidity timevalue
3063 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
3064 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
3066 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
3067 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3068 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
3069 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
3070 max_path_offset = cmp::max(
3071 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
3072 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
3073 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
3075 // Add 'shadow' CLTV offset to the final hop
3076 if let Some(tail) = path.blinded_tail.as_mut() {
3077 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
3078 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
3080 if let Some(last_hop) = path.hops.last_mut() {
3081 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
3082 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
3087 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
3088 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
3090 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
3091 pub fn build_route_from_hops<L: Deref, GL: Deref>(
3092 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3093 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
3094 ) -> Result<Route, LightningError>
3095 where L::Target: Logger, GL::Target: Logger {
3096 let graph_lock = network_graph.read_only();
3097 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
3098 &graph_lock, logger, random_seed_bytes)?;
3099 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
3103 fn build_route_from_hops_internal<L: Deref>(
3104 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3105 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
3106 ) -> Result<Route, LightningError> where L::Target: Logger {
3109 our_node_id: NodeId,
3110 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
3113 impl ScoreLookUp for HopScorer {
3114 type ScoreParams = ();
3115 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
3116 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
3118 let mut cur_id = self.our_node_id;
3119 for i in 0..self.hop_ids.len() {
3120 if let Some(next_id) = self.hop_ids[i] {
3121 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
3133 impl<'a> Writeable for HopScorer {
3135 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
3140 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
3141 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
3144 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
3145 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
3146 for i in 0..hops.len() {
3147 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
3150 let scorer = HopScorer { our_node_id, hop_ids };
3152 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
3157 use crate::blinded_path::{BlindedHop, BlindedPath};
3158 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
3159 use crate::routing::utxo::UtxoResult;
3160 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
3161 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3162 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop};
3163 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3164 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3165 use crate::chain::transaction::OutPoint;
3166 use crate::sign::EntropySource;
3167 use crate::ln::ChannelId;
3168 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3169 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3170 use crate::ln::channelmanager;
3171 use crate::offers::invoice::BlindedPayInfo;
3172 use crate::util::config::UserConfig;
3173 use crate::util::test_utils as ln_test_utils;
3174 use crate::util::chacha20::ChaCha20;
3175 use crate::util::ser::{Readable, Writeable};
3177 use crate::util::ser::Writer;
3179 use bitcoin::hashes::Hash;
3180 use bitcoin::network::constants::Network;
3181 use bitcoin::blockdata::constants::ChainHash;
3182 use bitcoin::blockdata::script::Builder;
3183 use bitcoin::blockdata::opcodes;
3184 use bitcoin::blockdata::transaction::TxOut;
3185 use bitcoin::hashes::hex::FromHex;
3186 use bitcoin::secp256k1::{PublicKey,SecretKey};
3187 use bitcoin::secp256k1::Secp256k1;
3189 use crate::io::Cursor;
3190 use crate::prelude::*;
3191 use crate::sync::Arc;
3193 use core::convert::TryInto;
3195 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3196 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
3197 channelmanager::ChannelDetails {
3198 channel_id: ChannelId::new_zero(),
3199 counterparty: channelmanager::ChannelCounterparty {
3202 unspendable_punishment_reserve: 0,
3203 forwarding_info: None,
3204 outbound_htlc_minimum_msat: None,
3205 outbound_htlc_maximum_msat: None,
3207 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3210 outbound_scid_alias: None,
3211 inbound_scid_alias: None,
3212 channel_value_satoshis: 0,
3215 outbound_capacity_msat,
3216 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3217 next_outbound_htlc_minimum_msat: 0,
3218 inbound_capacity_msat: 42,
3219 unspendable_punishment_reserve: None,
3220 confirmations_required: None,
3221 confirmations: None,
3222 force_close_spend_delay: None,
3223 is_outbound: true, is_channel_ready: true,
3224 is_usable: true, is_public: true,
3225 inbound_htlc_minimum_msat: None,
3226 inbound_htlc_maximum_msat: None,
3228 feerate_sat_per_1000_weight: None,
3229 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
3234 fn simple_route_test() {
3235 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3236 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3237 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3238 let scorer = ln_test_utils::TestScorer::new();
3239 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3240 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3242 // Simple route to 2 via 1
3244 let route_params = RouteParameters::from_payment_params_and_value(
3245 payment_params.clone(), 0);
3246 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3247 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3248 &Default::default(), &random_seed_bytes) {
3249 assert_eq!(err, "Cannot send a payment of 0 msat");
3250 } else { panic!(); }
3252 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3253 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3254 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3255 assert_eq!(route.paths[0].hops.len(), 2);
3257 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3258 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3259 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3260 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3261 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3262 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3264 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3265 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3266 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3267 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3268 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3269 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3273 fn invalid_first_hop_test() {
3274 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3275 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3276 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3277 let scorer = ln_test_utils::TestScorer::new();
3278 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3279 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3281 // Simple route to 2 via 1
3283 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3285 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3286 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3287 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3288 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3289 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3290 } else { panic!(); }
3292 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3293 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3294 assert_eq!(route.paths[0].hops.len(), 2);
3298 fn htlc_minimum_test() {
3299 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3300 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3301 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3302 let scorer = ln_test_utils::TestScorer::new();
3303 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3304 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3306 // Simple route to 2 via 1
3308 // Disable other paths
3309 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3310 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3311 short_channel_id: 12,
3313 flags: 2, // to disable
3314 cltv_expiry_delta: 0,
3315 htlc_minimum_msat: 0,
3316 htlc_maximum_msat: MAX_VALUE_MSAT,
3318 fee_proportional_millionths: 0,
3319 excess_data: Vec::new()
3321 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3322 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3323 short_channel_id: 3,
3325 flags: 2, // to disable
3326 cltv_expiry_delta: 0,
3327 htlc_minimum_msat: 0,
3328 htlc_maximum_msat: MAX_VALUE_MSAT,
3330 fee_proportional_millionths: 0,
3331 excess_data: Vec::new()
3333 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3334 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3335 short_channel_id: 13,
3337 flags: 2, // to disable
3338 cltv_expiry_delta: 0,
3339 htlc_minimum_msat: 0,
3340 htlc_maximum_msat: MAX_VALUE_MSAT,
3342 fee_proportional_millionths: 0,
3343 excess_data: Vec::new()
3345 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3346 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3347 short_channel_id: 6,
3349 flags: 2, // to disable
3350 cltv_expiry_delta: 0,
3351 htlc_minimum_msat: 0,
3352 htlc_maximum_msat: MAX_VALUE_MSAT,
3354 fee_proportional_millionths: 0,
3355 excess_data: Vec::new()
3357 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3358 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3359 short_channel_id: 7,
3361 flags: 2, // to disable
3362 cltv_expiry_delta: 0,
3363 htlc_minimum_msat: 0,
3364 htlc_maximum_msat: MAX_VALUE_MSAT,
3366 fee_proportional_millionths: 0,
3367 excess_data: Vec::new()
3370 // Check against amount_to_transfer_over_msat.
3371 // Set minimal HTLC of 200_000_000 msat.
3372 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3373 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3374 short_channel_id: 2,
3377 cltv_expiry_delta: 0,
3378 htlc_minimum_msat: 200_000_000,
3379 htlc_maximum_msat: MAX_VALUE_MSAT,
3381 fee_proportional_millionths: 0,
3382 excess_data: Vec::new()
3385 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3387 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3388 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3389 short_channel_id: 4,
3392 cltv_expiry_delta: 0,
3393 htlc_minimum_msat: 0,
3394 htlc_maximum_msat: 199_999_999,
3396 fee_proportional_millionths: 0,
3397 excess_data: Vec::new()
3400 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3401 let route_params = RouteParameters::from_payment_params_and_value(
3402 payment_params, 199_999_999);
3403 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3404 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3405 &Default::default(), &random_seed_bytes) {
3406 assert_eq!(err, "Failed to find a path to the given destination");
3407 } else { panic!(); }
3409 // Lift the restriction on the first hop.
3410 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3411 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3412 short_channel_id: 2,
3415 cltv_expiry_delta: 0,
3416 htlc_minimum_msat: 0,
3417 htlc_maximum_msat: MAX_VALUE_MSAT,
3419 fee_proportional_millionths: 0,
3420 excess_data: Vec::new()
3423 // A payment above the minimum should pass
3424 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3425 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3426 assert_eq!(route.paths[0].hops.len(), 2);
3430 fn htlc_minimum_overpay_test() {
3431 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3432 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3433 let config = UserConfig::default();
3434 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3435 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3437 let scorer = ln_test_utils::TestScorer::new();
3438 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3439 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3441 // A route to node#2 via two paths.
3442 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3443 // Thus, they can't send 60 without overpaying.
3444 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3445 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3446 short_channel_id: 2,
3449 cltv_expiry_delta: 0,
3450 htlc_minimum_msat: 35_000,
3451 htlc_maximum_msat: 40_000,
3453 fee_proportional_millionths: 0,
3454 excess_data: Vec::new()
3456 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3457 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3458 short_channel_id: 12,
3461 cltv_expiry_delta: 0,
3462 htlc_minimum_msat: 35_000,
3463 htlc_maximum_msat: 40_000,
3465 fee_proportional_millionths: 0,
3466 excess_data: Vec::new()
3470 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3471 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3472 short_channel_id: 13,
3475 cltv_expiry_delta: 0,
3476 htlc_minimum_msat: 0,
3477 htlc_maximum_msat: MAX_VALUE_MSAT,
3479 fee_proportional_millionths: 0,
3480 excess_data: Vec::new()
3482 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3483 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3484 short_channel_id: 4,
3487 cltv_expiry_delta: 0,
3488 htlc_minimum_msat: 0,
3489 htlc_maximum_msat: MAX_VALUE_MSAT,
3491 fee_proportional_millionths: 0,
3492 excess_data: Vec::new()
3495 // Disable other paths
3496 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3497 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3498 short_channel_id: 1,
3500 flags: 2, // to disable
3501 cltv_expiry_delta: 0,
3502 htlc_minimum_msat: 0,
3503 htlc_maximum_msat: MAX_VALUE_MSAT,
3505 fee_proportional_millionths: 0,
3506 excess_data: Vec::new()
3509 let mut route_params = RouteParameters::from_payment_params_and_value(
3510 payment_params.clone(), 60_000);
3511 route_params.max_total_routing_fee_msat = Some(15_000);
3512 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3513 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3514 // Overpay fees to hit htlc_minimum_msat.
3515 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3516 // TODO: this could be better balanced to overpay 10k and not 15k.
3517 assert_eq!(overpaid_fees, 15_000);
3519 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3520 // while taking even more fee to match htlc_minimum_msat.
3521 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3522 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3523 short_channel_id: 12,
3526 cltv_expiry_delta: 0,
3527 htlc_minimum_msat: 65_000,
3528 htlc_maximum_msat: 80_000,
3530 fee_proportional_millionths: 0,
3531 excess_data: Vec::new()
3533 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3534 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3535 short_channel_id: 2,
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[1], UnsignedChannelUpdate {
3546 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3547 short_channel_id: 4,
3550 cltv_expiry_delta: 0,
3551 htlc_minimum_msat: 0,
3552 htlc_maximum_msat: MAX_VALUE_MSAT,
3554 fee_proportional_millionths: 100_000,
3555 excess_data: Vec::new()
3558 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3559 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3560 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3561 assert_eq!(route.paths.len(), 1);
3562 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3563 let fees = route.paths[0].hops[0].fee_msat;
3564 assert_eq!(fees, 5_000);
3566 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3567 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3568 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3569 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3570 // the other channel.
3571 assert_eq!(route.paths.len(), 1);
3572 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3573 let fees = route.paths[0].hops[0].fee_msat;
3574 assert_eq!(fees, 5_000);
3578 fn htlc_minimum_recipient_overpay_test() {
3579 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3580 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3581 let config = UserConfig::default();
3582 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3583 let scorer = ln_test_utils::TestScorer::new();
3584 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3585 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3587 // Route to node2 over a single path which requires overpaying the recipient themselves.
3589 // First disable all paths except the us -> node1 -> node2 path
3590 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3591 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3592 short_channel_id: 13,
3595 cltv_expiry_delta: 0,
3596 htlc_minimum_msat: 0,
3597 htlc_maximum_msat: 0,
3599 fee_proportional_millionths: 0,
3600 excess_data: Vec::new()
3603 // Set channel 4 to free but with a high htlc_minimum_msat
3604 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3605 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3606 short_channel_id: 4,
3609 cltv_expiry_delta: 0,
3610 htlc_minimum_msat: 15_000,
3611 htlc_maximum_msat: MAX_VALUE_MSAT,
3613 fee_proportional_millionths: 0,
3614 excess_data: Vec::new()
3617 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3618 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3619 // what we try to find a route for, so this test only just happens to work out to exactly
3621 let mut route_params = RouteParameters::from_payment_params_and_value(
3622 payment_params.clone(), 5_000);
3623 route_params.max_total_routing_fee_msat = Some(9_999);
3624 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3625 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3626 &Default::default(), &random_seed_bytes) {
3627 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3628 } else { panic!(); }
3630 let mut route_params = RouteParameters::from_payment_params_and_value(
3631 payment_params.clone(), 5_000);
3632 route_params.max_total_routing_fee_msat = Some(10_000);
3633 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3634 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3635 assert_eq!(route.get_total_fees(), 10_000);
3639 fn disable_channels_test() {
3640 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3641 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3642 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3643 let scorer = ln_test_utils::TestScorer::new();
3644 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3645 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3647 // // Disable channels 4 and 12 by flags=2
3648 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3649 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3650 short_channel_id: 4,
3652 flags: 2, // to disable
3653 cltv_expiry_delta: 0,
3654 htlc_minimum_msat: 0,
3655 htlc_maximum_msat: MAX_VALUE_MSAT,
3657 fee_proportional_millionths: 0,
3658 excess_data: Vec::new()
3660 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3661 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3662 short_channel_id: 12,
3664 flags: 2, // to disable
3665 cltv_expiry_delta: 0,
3666 htlc_minimum_msat: 0,
3667 htlc_maximum_msat: MAX_VALUE_MSAT,
3669 fee_proportional_millionths: 0,
3670 excess_data: Vec::new()
3673 // If all the channels require some features we don't understand, route should fail
3674 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3675 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3676 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3677 &Default::default(), &random_seed_bytes) {
3678 assert_eq!(err, "Failed to find a path to the given destination");
3679 } else { panic!(); }
3681 // If we specify a channel to node7, that overrides our local channel view and that gets used
3682 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3683 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3684 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3685 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3686 &Default::default(), &random_seed_bytes).unwrap();
3687 assert_eq!(route.paths[0].hops.len(), 2);
3689 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3690 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3691 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3692 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3693 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3694 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3696 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3697 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3698 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3699 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3700 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3701 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3705 fn disable_node_test() {
3706 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3707 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3708 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3709 let scorer = ln_test_utils::TestScorer::new();
3710 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3711 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3713 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3714 let mut unknown_features = NodeFeatures::empty();
3715 unknown_features.set_unknown_feature_required();
3716 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3717 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3718 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3720 // If all nodes require some features we don't understand, route should fail
3721 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3722 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3723 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3724 &Default::default(), &random_seed_bytes) {
3725 assert_eq!(err, "Failed to find a path to the given destination");
3726 } else { panic!(); }
3728 // If we specify a channel to node7, that overrides our local channel view and that gets used
3729 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3730 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3731 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3732 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3733 &Default::default(), &random_seed_bytes).unwrap();
3734 assert_eq!(route.paths[0].hops.len(), 2);
3736 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3737 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3738 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3739 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3740 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3741 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3743 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3744 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3745 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3746 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3747 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3748 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3750 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3751 // naively) assume that the user checked the feature bits on the invoice, which override
3752 // the node_announcement.
3756 fn our_chans_test() {
3757 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3758 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3759 let scorer = ln_test_utils::TestScorer::new();
3760 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3761 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3763 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3764 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3765 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3766 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3767 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3768 assert_eq!(route.paths[0].hops.len(), 3);
3770 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3771 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3772 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3773 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3774 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3775 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3777 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3778 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3779 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3780 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3781 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3782 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3784 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3785 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3786 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3787 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3788 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3789 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3791 // If we specify a channel to node7, that overrides our local channel view and that gets used
3792 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3793 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3794 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3795 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3796 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3797 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3798 &Default::default(), &random_seed_bytes).unwrap();
3799 assert_eq!(route.paths[0].hops.len(), 2);
3801 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3802 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3803 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3804 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3805 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3806 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3808 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3809 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3810 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3811 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3812 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3813 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3816 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3817 let zero_fees = RoutingFees {
3819 proportional_millionths: 0,
3821 vec![RouteHint(vec![RouteHintHop {
3822 src_node_id: nodes[3],
3823 short_channel_id: 8,
3825 cltv_expiry_delta: (8 << 4) | 1,
3826 htlc_minimum_msat: None,
3827 htlc_maximum_msat: None,
3829 ]), RouteHint(vec![RouteHintHop {
3830 src_node_id: nodes[4],
3831 short_channel_id: 9,
3834 proportional_millionths: 0,
3836 cltv_expiry_delta: (9 << 4) | 1,
3837 htlc_minimum_msat: None,
3838 htlc_maximum_msat: None,
3839 }]), RouteHint(vec![RouteHintHop {
3840 src_node_id: nodes[5],
3841 short_channel_id: 10,
3843 cltv_expiry_delta: (10 << 4) | 1,
3844 htlc_minimum_msat: None,
3845 htlc_maximum_msat: None,
3849 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3850 let zero_fees = RoutingFees {
3852 proportional_millionths: 0,
3854 vec![RouteHint(vec![RouteHintHop {
3855 src_node_id: nodes[2],
3856 short_channel_id: 5,
3859 proportional_millionths: 0,
3861 cltv_expiry_delta: (5 << 4) | 1,
3862 htlc_minimum_msat: None,
3863 htlc_maximum_msat: None,
3865 src_node_id: nodes[3],
3866 short_channel_id: 8,
3868 cltv_expiry_delta: (8 << 4) | 1,
3869 htlc_minimum_msat: None,
3870 htlc_maximum_msat: None,
3872 ]), RouteHint(vec![RouteHintHop {
3873 src_node_id: nodes[4],
3874 short_channel_id: 9,
3877 proportional_millionths: 0,
3879 cltv_expiry_delta: (9 << 4) | 1,
3880 htlc_minimum_msat: None,
3881 htlc_maximum_msat: None,
3882 }]), RouteHint(vec![RouteHintHop {
3883 src_node_id: nodes[5],
3884 short_channel_id: 10,
3886 cltv_expiry_delta: (10 << 4) | 1,
3887 htlc_minimum_msat: None,
3888 htlc_maximum_msat: None,
3893 fn partial_route_hint_test() {
3894 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3895 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3896 let scorer = ln_test_utils::TestScorer::new();
3897 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3898 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3900 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3901 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3902 // RouteHint may be partially used by the algo to build the best path.
3904 // First check that last hop can't have its source as the payee.
3905 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3906 src_node_id: nodes[6],
3907 short_channel_id: 8,
3910 proportional_millionths: 0,
3912 cltv_expiry_delta: (8 << 4) | 1,
3913 htlc_minimum_msat: None,
3914 htlc_maximum_msat: None,
3917 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3918 invalid_last_hops.push(invalid_last_hop);
3920 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3921 .with_route_hints(invalid_last_hops).unwrap();
3922 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3923 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3924 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3925 &Default::default(), &random_seed_bytes) {
3926 assert_eq!(err, "Route hint cannot have the payee as the source.");
3927 } else { panic!(); }
3930 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3931 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3932 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3933 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3934 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3935 assert_eq!(route.paths[0].hops.len(), 5);
3937 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3938 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3939 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3940 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3941 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3942 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3944 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3945 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3946 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3947 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3948 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3949 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3951 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3952 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3953 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3954 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3955 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3956 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3958 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3959 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3960 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3961 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3962 // If we have a peer in the node map, we'll use their features here since we don't have
3963 // a way of figuring out their features from the invoice:
3964 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3965 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3967 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3968 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3969 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3970 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3971 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3972 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3975 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3976 let zero_fees = RoutingFees {
3978 proportional_millionths: 0,
3980 vec![RouteHint(vec![RouteHintHop {
3981 src_node_id: nodes[3],
3982 short_channel_id: 8,
3984 cltv_expiry_delta: (8 << 4) | 1,
3985 htlc_minimum_msat: None,
3986 htlc_maximum_msat: None,
3987 }]), RouteHint(vec![
3989 ]), RouteHint(vec![RouteHintHop {
3990 src_node_id: nodes[5],
3991 short_channel_id: 10,
3993 cltv_expiry_delta: (10 << 4) | 1,
3994 htlc_minimum_msat: None,
3995 htlc_maximum_msat: None,
4000 fn ignores_empty_last_hops_test() {
4001 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4002 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4003 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
4004 let scorer = ln_test_utils::TestScorer::new();
4005 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4006 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4008 // Test handling of an empty RouteHint passed in Invoice.
4009 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4010 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4011 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4012 assert_eq!(route.paths[0].hops.len(), 5);
4014 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4015 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4016 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4017 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4018 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4019 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4021 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4022 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4023 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4024 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4025 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4026 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4028 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4029 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4030 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4031 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4032 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4033 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4035 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4036 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4037 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4038 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4039 // If we have a peer in the node map, we'll use their features here since we don't have
4040 // a way of figuring out their features from the invoice:
4041 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4042 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4044 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4045 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4046 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4047 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4048 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4049 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4052 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
4054 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
4055 let zero_fees = RoutingFees {
4057 proportional_millionths: 0,
4059 vec![RouteHint(vec![RouteHintHop {
4060 src_node_id: hint_hops[0],
4061 short_channel_id: 0xff00,
4064 proportional_millionths: 0,
4066 cltv_expiry_delta: (5 << 4) | 1,
4067 htlc_minimum_msat: None,
4068 htlc_maximum_msat: None,
4070 src_node_id: hint_hops[1],
4071 short_channel_id: 0xff01,
4073 cltv_expiry_delta: (8 << 4) | 1,
4074 htlc_minimum_msat: None,
4075 htlc_maximum_msat: None,
4080 fn multi_hint_last_hops_test() {
4081 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4082 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4083 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
4084 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4085 let scorer = ln_test_utils::TestScorer::new();
4086 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4087 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4088 // Test through channels 2, 3, 0xff00, 0xff01.
4089 // Test shows that multiple hop hints are considered.
4091 // Disabling channels 6 & 7 by flags=2
4092 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4093 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4094 short_channel_id: 6,
4096 flags: 2, // to disable
4097 cltv_expiry_delta: 0,
4098 htlc_minimum_msat: 0,
4099 htlc_maximum_msat: MAX_VALUE_MSAT,
4101 fee_proportional_millionths: 0,
4102 excess_data: Vec::new()
4104 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4105 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4106 short_channel_id: 7,
4108 flags: 2, // to disable
4109 cltv_expiry_delta: 0,
4110 htlc_minimum_msat: 0,
4111 htlc_maximum_msat: MAX_VALUE_MSAT,
4113 fee_proportional_millionths: 0,
4114 excess_data: Vec::new()
4117 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4118 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4119 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4120 assert_eq!(route.paths[0].hops.len(), 4);
4122 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4123 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4124 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4125 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4126 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4127 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4129 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4130 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4131 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4132 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4133 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4134 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4136 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
4137 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4138 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4139 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4140 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
4141 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4143 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4144 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4145 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4146 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4147 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4148 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4152 fn private_multi_hint_last_hops_test() {
4153 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4154 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4156 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
4157 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
4159 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
4160 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4161 let scorer = ln_test_utils::TestScorer::new();
4162 // Test through channels 2, 3, 0xff00, 0xff01.
4163 // Test shows that multiple hop hints are considered.
4165 // Disabling channels 6 & 7 by flags=2
4166 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4167 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4168 short_channel_id: 6,
4170 flags: 2, // to disable
4171 cltv_expiry_delta: 0,
4172 htlc_minimum_msat: 0,
4173 htlc_maximum_msat: MAX_VALUE_MSAT,
4175 fee_proportional_millionths: 0,
4176 excess_data: Vec::new()
4178 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4179 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4180 short_channel_id: 7,
4182 flags: 2, // to disable
4183 cltv_expiry_delta: 0,
4184 htlc_minimum_msat: 0,
4185 htlc_maximum_msat: MAX_VALUE_MSAT,
4187 fee_proportional_millionths: 0,
4188 excess_data: Vec::new()
4191 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4192 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4193 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4194 assert_eq!(route.paths[0].hops.len(), 4);
4196 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4197 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4198 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4199 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4200 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4201 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4203 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4204 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4205 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4206 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4207 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4208 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4210 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4211 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4212 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4213 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4214 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4215 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4217 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4218 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4219 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4220 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4221 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4222 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4225 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4226 let zero_fees = RoutingFees {
4228 proportional_millionths: 0,
4230 vec![RouteHint(vec![RouteHintHop {
4231 src_node_id: nodes[4],
4232 short_channel_id: 11,
4234 cltv_expiry_delta: (11 << 4) | 1,
4235 htlc_minimum_msat: None,
4236 htlc_maximum_msat: None,
4238 src_node_id: nodes[3],
4239 short_channel_id: 8,
4241 cltv_expiry_delta: (8 << 4) | 1,
4242 htlc_minimum_msat: None,
4243 htlc_maximum_msat: None,
4244 }]), RouteHint(vec![RouteHintHop {
4245 src_node_id: nodes[4],
4246 short_channel_id: 9,
4249 proportional_millionths: 0,
4251 cltv_expiry_delta: (9 << 4) | 1,
4252 htlc_minimum_msat: None,
4253 htlc_maximum_msat: None,
4254 }]), RouteHint(vec![RouteHintHop {
4255 src_node_id: nodes[5],
4256 short_channel_id: 10,
4258 cltv_expiry_delta: (10 << 4) | 1,
4259 htlc_minimum_msat: None,
4260 htlc_maximum_msat: None,
4265 fn last_hops_with_public_channel_test() {
4266 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4267 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4268 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4269 let scorer = ln_test_utils::TestScorer::new();
4270 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4271 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4272 // This test shows that public routes can be present in the invoice
4273 // which would be handled in the same manner.
4275 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4276 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4277 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4278 assert_eq!(route.paths[0].hops.len(), 5);
4280 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4281 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4282 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4283 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4284 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4285 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4287 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4288 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4289 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4290 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4291 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4292 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4294 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4295 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4296 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4297 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4298 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4299 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4301 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4302 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4303 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4304 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4305 // If we have a peer in the node map, we'll use their features here since we don't have
4306 // a way of figuring out their features from the invoice:
4307 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4308 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4310 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4311 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4312 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4313 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4314 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4315 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4319 fn our_chans_last_hop_connect_test() {
4320 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4321 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4322 let scorer = ln_test_utils::TestScorer::new();
4323 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4324 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4326 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4327 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4328 let mut last_hops = last_hops(&nodes);
4329 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4330 .with_route_hints(last_hops.clone()).unwrap();
4331 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4332 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4333 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4334 &Default::default(), &random_seed_bytes).unwrap();
4335 assert_eq!(route.paths[0].hops.len(), 2);
4337 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4338 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4339 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4340 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4341 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4342 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4344 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4345 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4346 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4347 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4348 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4349 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4351 last_hops[0].0[0].fees.base_msat = 1000;
4353 // Revert to via 6 as the fee on 8 goes up
4354 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4355 .with_route_hints(last_hops).unwrap();
4356 let route_params = RouteParameters::from_payment_params_and_value(
4357 payment_params.clone(), 100);
4358 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4359 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4360 assert_eq!(route.paths[0].hops.len(), 4);
4362 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4363 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4364 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4365 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4366 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4367 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4369 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4370 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4371 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4372 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4373 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4374 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4376 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4377 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4378 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4379 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4380 // If we have a peer in the node map, we'll use their features here since we don't have
4381 // a way of figuring out their features from the invoice:
4382 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4383 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4385 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4386 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4387 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4388 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4389 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4390 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4392 // ...but still use 8 for larger payments as 6 has a variable feerate
4393 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4394 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4395 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4396 assert_eq!(route.paths[0].hops.len(), 5);
4398 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4399 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4400 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4401 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4402 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4403 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4405 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4406 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4407 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4408 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4409 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4410 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4412 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4413 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4414 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4415 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4416 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4417 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4419 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4420 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4421 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4422 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4423 // If we have a peer in the node map, we'll use their features here since we don't have
4424 // a way of figuring out their features from the invoice:
4425 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4426 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4428 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4429 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4430 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4431 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4432 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4433 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4436 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> {
4437 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4438 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4439 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4441 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4442 let last_hops = RouteHint(vec![RouteHintHop {
4443 src_node_id: middle_node_id,
4444 short_channel_id: 8,
4447 proportional_millionths: last_hop_fee_prop,
4449 cltv_expiry_delta: (8 << 4) | 1,
4450 htlc_minimum_msat: None,
4451 htlc_maximum_msat: last_hop_htlc_max,
4453 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4454 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4455 let scorer = ln_test_utils::TestScorer::new();
4456 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4457 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4458 let logger = ln_test_utils::TestLogger::new();
4459 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4460 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4461 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4462 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4463 &random_seed_bytes);
4468 fn unannounced_path_test() {
4469 // We should be able to send a payment to a destination without any help of a routing graph
4470 // if we have a channel with a common counterparty that appears in the first and last hop
4472 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4474 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4475 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4476 assert_eq!(route.paths[0].hops.len(), 2);
4478 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4479 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4480 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4481 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4482 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4483 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4485 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4486 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4487 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4488 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4489 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4490 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4494 fn overflow_unannounced_path_test_liquidity_underflow() {
4495 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4496 // the last-hop had a fee which overflowed a u64, we'd panic.
4497 // This was due to us adding the first-hop from us unconditionally, causing us to think
4498 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4499 // In this test, we previously hit a subtraction underflow due to having less available
4500 // liquidity at the last hop than 0.
4501 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());
4505 fn overflow_unannounced_path_test_feerate_overflow() {
4506 // This tests for the same case as above, except instead of hitting a subtraction
4507 // underflow, we hit a case where the fee charged at a hop overflowed.
4508 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());
4512 fn available_amount_while_routing_test() {
4513 // Tests whether we choose the correct available channel amount while routing.
4515 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4516 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4517 let scorer = ln_test_utils::TestScorer::new();
4518 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4519 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4520 let config = UserConfig::default();
4521 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4522 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4525 // We will use a simple single-path route from
4526 // our node to node2 via node0: channels {1, 3}.
4528 // First disable all other paths.
4529 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4530 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4531 short_channel_id: 2,
4534 cltv_expiry_delta: 0,
4535 htlc_minimum_msat: 0,
4536 htlc_maximum_msat: 100_000,
4538 fee_proportional_millionths: 0,
4539 excess_data: Vec::new()
4541 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4542 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4543 short_channel_id: 12,
4546 cltv_expiry_delta: 0,
4547 htlc_minimum_msat: 0,
4548 htlc_maximum_msat: 100_000,
4550 fee_proportional_millionths: 0,
4551 excess_data: Vec::new()
4554 // Make the first channel (#1) very permissive,
4555 // and we will be testing all limits on the second channel.
4556 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4557 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4558 short_channel_id: 1,
4561 cltv_expiry_delta: 0,
4562 htlc_minimum_msat: 0,
4563 htlc_maximum_msat: 1_000_000_000,
4565 fee_proportional_millionths: 0,
4566 excess_data: Vec::new()
4569 // First, let's see if routing works if we have absolutely no idea about the available amount.
4570 // In this case, it should be set to 250_000 sats.
4571 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4572 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4573 short_channel_id: 3,
4576 cltv_expiry_delta: 0,
4577 htlc_minimum_msat: 0,
4578 htlc_maximum_msat: 250_000_000,
4580 fee_proportional_millionths: 0,
4581 excess_data: Vec::new()
4585 // Attempt to route more than available results in a failure.
4586 let route_params = RouteParameters::from_payment_params_and_value(
4587 payment_params.clone(), 250_000_001);
4588 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4589 &our_id, &route_params, &network_graph.read_only(), None,
4590 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4591 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4592 } else { panic!(); }
4596 // Now, attempt to route an exact amount we have should be fine.
4597 let route_params = RouteParameters::from_payment_params_and_value(
4598 payment_params.clone(), 250_000_000);
4599 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4600 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4601 assert_eq!(route.paths.len(), 1);
4602 let path = route.paths.last().unwrap();
4603 assert_eq!(path.hops.len(), 2);
4604 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4605 assert_eq!(path.final_value_msat(), 250_000_000);
4608 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4609 // Disable channel #1 and use another first hop.
4610 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4611 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4612 short_channel_id: 1,
4615 cltv_expiry_delta: 0,
4616 htlc_minimum_msat: 0,
4617 htlc_maximum_msat: 1_000_000_000,
4619 fee_proportional_millionths: 0,
4620 excess_data: Vec::new()
4623 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4624 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4627 // Attempt to route more than available results in a failure.
4628 let route_params = RouteParameters::from_payment_params_and_value(
4629 payment_params.clone(), 200_000_001);
4630 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4631 &our_id, &route_params, &network_graph.read_only(),
4632 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4633 &Default::default(), &random_seed_bytes) {
4634 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4635 } else { panic!(); }
4639 // Now, attempt to route an exact amount we have should be fine.
4640 let route_params = RouteParameters::from_payment_params_and_value(
4641 payment_params.clone(), 200_000_000);
4642 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4643 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4644 &Default::default(), &random_seed_bytes).unwrap();
4645 assert_eq!(route.paths.len(), 1);
4646 let path = route.paths.last().unwrap();
4647 assert_eq!(path.hops.len(), 2);
4648 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4649 assert_eq!(path.final_value_msat(), 200_000_000);
4652 // Enable channel #1 back.
4653 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4654 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4655 short_channel_id: 1,
4658 cltv_expiry_delta: 0,
4659 htlc_minimum_msat: 0,
4660 htlc_maximum_msat: 1_000_000_000,
4662 fee_proportional_millionths: 0,
4663 excess_data: Vec::new()
4667 // Now let's see if routing works if we know only htlc_maximum_msat.
4668 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4669 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4670 short_channel_id: 3,
4673 cltv_expiry_delta: 0,
4674 htlc_minimum_msat: 0,
4675 htlc_maximum_msat: 15_000,
4677 fee_proportional_millionths: 0,
4678 excess_data: Vec::new()
4682 // Attempt to route more than available results in a failure.
4683 let route_params = RouteParameters::from_payment_params_and_value(
4684 payment_params.clone(), 15_001);
4685 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4686 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4687 &scorer, &Default::default(), &random_seed_bytes) {
4688 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4689 } else { panic!(); }
4693 // Now, attempt to route an exact amount we have should be fine.
4694 let route_params = RouteParameters::from_payment_params_and_value(
4695 payment_params.clone(), 15_000);
4696 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4697 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4698 assert_eq!(route.paths.len(), 1);
4699 let path = route.paths.last().unwrap();
4700 assert_eq!(path.hops.len(), 2);
4701 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4702 assert_eq!(path.final_value_msat(), 15_000);
4705 // Now let's see if routing works if we know only capacity from the UTXO.
4707 // We can't change UTXO capacity on the fly, so we'll disable
4708 // the existing channel and add another one with the capacity we need.
4709 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4710 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4711 short_channel_id: 3,
4714 cltv_expiry_delta: 0,
4715 htlc_minimum_msat: 0,
4716 htlc_maximum_msat: MAX_VALUE_MSAT,
4718 fee_proportional_millionths: 0,
4719 excess_data: Vec::new()
4722 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4723 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4724 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4725 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4726 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4728 *chain_monitor.utxo_ret.lock().unwrap() =
4729 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4730 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4732 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4733 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4734 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4735 short_channel_id: 333,
4738 cltv_expiry_delta: (3 << 4) | 1,
4739 htlc_minimum_msat: 0,
4740 htlc_maximum_msat: 15_000,
4742 fee_proportional_millionths: 0,
4743 excess_data: Vec::new()
4745 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4746 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4747 short_channel_id: 333,
4750 cltv_expiry_delta: (3 << 4) | 2,
4751 htlc_minimum_msat: 0,
4752 htlc_maximum_msat: 15_000,
4754 fee_proportional_millionths: 0,
4755 excess_data: Vec::new()
4759 // Attempt to route more than available results in a failure.
4760 let route_params = RouteParameters::from_payment_params_and_value(
4761 payment_params.clone(), 15_001);
4762 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4763 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4764 &scorer, &Default::default(), &random_seed_bytes) {
4765 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4766 } else { panic!(); }
4770 // Now, attempt to route an exact amount we have should be fine.
4771 let route_params = RouteParameters::from_payment_params_and_value(
4772 payment_params.clone(), 15_000);
4773 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4774 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4775 assert_eq!(route.paths.len(), 1);
4776 let path = route.paths.last().unwrap();
4777 assert_eq!(path.hops.len(), 2);
4778 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4779 assert_eq!(path.final_value_msat(), 15_000);
4782 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4783 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4784 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4785 short_channel_id: 333,
4788 cltv_expiry_delta: 0,
4789 htlc_minimum_msat: 0,
4790 htlc_maximum_msat: 10_000,
4792 fee_proportional_millionths: 0,
4793 excess_data: Vec::new()
4797 // Attempt to route more than available results in a failure.
4798 let route_params = RouteParameters::from_payment_params_and_value(
4799 payment_params.clone(), 10_001);
4800 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4801 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4802 &scorer, &Default::default(), &random_seed_bytes) {
4803 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4804 } else { panic!(); }
4808 // Now, attempt to route an exact amount we have should be fine.
4809 let route_params = RouteParameters::from_payment_params_and_value(
4810 payment_params.clone(), 10_000);
4811 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4812 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4813 assert_eq!(route.paths.len(), 1);
4814 let path = route.paths.last().unwrap();
4815 assert_eq!(path.hops.len(), 2);
4816 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4817 assert_eq!(path.final_value_msat(), 10_000);
4822 fn available_liquidity_last_hop_test() {
4823 // Check that available liquidity properly limits the path even when only
4824 // one of the latter hops is limited.
4825 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4826 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4827 let scorer = ln_test_utils::TestScorer::new();
4828 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4829 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4830 let config = UserConfig::default();
4831 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4832 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4835 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4836 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4837 // Total capacity: 50 sats.
4839 // Disable other potential paths.
4840 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4841 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4842 short_channel_id: 2,
4845 cltv_expiry_delta: 0,
4846 htlc_minimum_msat: 0,
4847 htlc_maximum_msat: 100_000,
4849 fee_proportional_millionths: 0,
4850 excess_data: Vec::new()
4852 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4853 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4854 short_channel_id: 7,
4857 cltv_expiry_delta: 0,
4858 htlc_minimum_msat: 0,
4859 htlc_maximum_msat: 100_000,
4861 fee_proportional_millionths: 0,
4862 excess_data: Vec::new()
4867 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4868 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4869 short_channel_id: 12,
4872 cltv_expiry_delta: 0,
4873 htlc_minimum_msat: 0,
4874 htlc_maximum_msat: 100_000,
4876 fee_proportional_millionths: 0,
4877 excess_data: Vec::new()
4879 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4880 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4881 short_channel_id: 13,
4884 cltv_expiry_delta: 0,
4885 htlc_minimum_msat: 0,
4886 htlc_maximum_msat: 100_000,
4888 fee_proportional_millionths: 0,
4889 excess_data: Vec::new()
4892 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4893 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4894 short_channel_id: 6,
4897 cltv_expiry_delta: 0,
4898 htlc_minimum_msat: 0,
4899 htlc_maximum_msat: 50_000,
4901 fee_proportional_millionths: 0,
4902 excess_data: Vec::new()
4904 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4905 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4906 short_channel_id: 11,
4909 cltv_expiry_delta: 0,
4910 htlc_minimum_msat: 0,
4911 htlc_maximum_msat: 100_000,
4913 fee_proportional_millionths: 0,
4914 excess_data: Vec::new()
4917 // Attempt to route more than available results in a failure.
4918 let route_params = RouteParameters::from_payment_params_and_value(
4919 payment_params.clone(), 60_000);
4920 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4921 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4922 &scorer, &Default::default(), &random_seed_bytes) {
4923 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4924 } else { panic!(); }
4928 // Now, attempt to route 49 sats (just a bit below the capacity).
4929 let route_params = RouteParameters::from_payment_params_and_value(
4930 payment_params.clone(), 49_000);
4931 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4932 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4933 assert_eq!(route.paths.len(), 1);
4934 let mut total_amount_paid_msat = 0;
4935 for path in &route.paths {
4936 assert_eq!(path.hops.len(), 4);
4937 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4938 total_amount_paid_msat += path.final_value_msat();
4940 assert_eq!(total_amount_paid_msat, 49_000);
4944 // Attempt to route an exact amount is also fine
4945 let route_params = RouteParameters::from_payment_params_and_value(
4946 payment_params, 50_000);
4947 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4948 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4949 assert_eq!(route.paths.len(), 1);
4950 let mut total_amount_paid_msat = 0;
4951 for path in &route.paths {
4952 assert_eq!(path.hops.len(), 4);
4953 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4954 total_amount_paid_msat += path.final_value_msat();
4956 assert_eq!(total_amount_paid_msat, 50_000);
4961 fn ignore_fee_first_hop_test() {
4962 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4963 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4964 let scorer = ln_test_utils::TestScorer::new();
4965 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4966 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4967 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4969 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4970 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4971 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4972 short_channel_id: 1,
4975 cltv_expiry_delta: 0,
4976 htlc_minimum_msat: 0,
4977 htlc_maximum_msat: 100_000,
4978 fee_base_msat: 1_000_000,
4979 fee_proportional_millionths: 0,
4980 excess_data: Vec::new()
4982 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4983 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4984 short_channel_id: 3,
4987 cltv_expiry_delta: 0,
4988 htlc_minimum_msat: 0,
4989 htlc_maximum_msat: 50_000,
4991 fee_proportional_millionths: 0,
4992 excess_data: Vec::new()
4996 let route_params = RouteParameters::from_payment_params_and_value(
4997 payment_params, 50_000);
4998 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4999 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5000 assert_eq!(route.paths.len(), 1);
5001 let mut total_amount_paid_msat = 0;
5002 for path in &route.paths {
5003 assert_eq!(path.hops.len(), 2);
5004 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5005 total_amount_paid_msat += path.final_value_msat();
5007 assert_eq!(total_amount_paid_msat, 50_000);
5012 fn simple_mpp_route_test() {
5013 let (secp_ctx, _, _, _, _) = build_graph();
5014 let (_, _, _, nodes) = get_nodes(&secp_ctx);
5015 let config = UserConfig::default();
5016 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5017 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5019 do_simple_mpp_route_test(clear_payment_params);
5021 // MPP to a 1-hop blinded path for nodes[2]
5022 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
5023 let blinded_path = BlindedPath {
5024 introduction_node_id: nodes[2],
5025 blinding_point: ln_test_utils::pubkey(42),
5026 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
5028 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
5030 fee_proportional_millionths: 0,
5031 htlc_minimum_msat: 0,
5032 htlc_maximum_msat: 0,
5033 cltv_expiry_delta: 0,
5034 features: BlindedHopFeatures::empty(),
5036 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
5037 .with_bolt12_features(bolt12_features.clone()).unwrap();
5038 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
5040 // MPP to 3 2-hop blinded paths
5041 let mut blinded_path_node_0 = blinded_path.clone();
5042 blinded_path_node_0.introduction_node_id = nodes[0];
5043 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
5044 let mut node_0_payinfo = blinded_payinfo.clone();
5045 node_0_payinfo.htlc_maximum_msat = 50_000;
5047 let mut blinded_path_node_7 = blinded_path_node_0.clone();
5048 blinded_path_node_7.introduction_node_id = nodes[7];
5049 let mut node_7_payinfo = blinded_payinfo.clone();
5050 node_7_payinfo.htlc_maximum_msat = 60_000;
5052 let mut blinded_path_node_1 = blinded_path_node_0.clone();
5053 blinded_path_node_1.introduction_node_id = nodes[1];
5054 let mut node_1_payinfo = blinded_payinfo.clone();
5055 node_1_payinfo.htlc_maximum_msat = 180_000;
5057 let two_hop_blinded_payment_params = PaymentParameters::blinded(
5059 (node_0_payinfo, blinded_path_node_0),
5060 (node_7_payinfo, blinded_path_node_7),
5061 (node_1_payinfo, blinded_path_node_1)
5063 .with_bolt12_features(bolt12_features).unwrap();
5064 do_simple_mpp_route_test(two_hop_blinded_payment_params);
5068 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
5069 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5070 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5071 let scorer = ln_test_utils::TestScorer::new();
5072 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5073 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5075 // We need a route consisting of 3 paths:
5076 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5077 // To achieve this, the amount being transferred should be around
5078 // the total capacity of these 3 paths.
5080 // First, we set limits on these (previously unlimited) channels.
5081 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
5083 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5084 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5085 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5086 short_channel_id: 1,
5089 cltv_expiry_delta: 0,
5090 htlc_minimum_msat: 0,
5091 htlc_maximum_msat: 100_000,
5093 fee_proportional_millionths: 0,
5094 excess_data: Vec::new()
5096 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5097 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5098 short_channel_id: 3,
5101 cltv_expiry_delta: 0,
5102 htlc_minimum_msat: 0,
5103 htlc_maximum_msat: 50_000,
5105 fee_proportional_millionths: 0,
5106 excess_data: Vec::new()
5109 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
5110 // (total limit 60).
5111 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5112 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5113 short_channel_id: 12,
5116 cltv_expiry_delta: 0,
5117 htlc_minimum_msat: 0,
5118 htlc_maximum_msat: 60_000,
5120 fee_proportional_millionths: 0,
5121 excess_data: Vec::new()
5123 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5124 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5125 short_channel_id: 13,
5128 cltv_expiry_delta: 0,
5129 htlc_minimum_msat: 0,
5130 htlc_maximum_msat: 60_000,
5132 fee_proportional_millionths: 0,
5133 excess_data: Vec::new()
5136 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
5137 // (total capacity 180 sats).
5138 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5139 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5140 short_channel_id: 2,
5143 cltv_expiry_delta: 0,
5144 htlc_minimum_msat: 0,
5145 htlc_maximum_msat: 200_000,
5147 fee_proportional_millionths: 0,
5148 excess_data: Vec::new()
5150 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5151 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5152 short_channel_id: 4,
5155 cltv_expiry_delta: 0,
5156 htlc_minimum_msat: 0,
5157 htlc_maximum_msat: 180_000,
5159 fee_proportional_millionths: 0,
5160 excess_data: Vec::new()
5164 // Attempt to route more than available results in a failure.
5165 let route_params = RouteParameters::from_payment_params_and_value(
5166 payment_params.clone(), 300_000);
5167 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5168 &our_id, &route_params, &network_graph.read_only(), None,
5169 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5170 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5171 } else { panic!(); }
5175 // Attempt to route while setting max_path_count to 0 results in a failure.
5176 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5177 let route_params = RouteParameters::from_payment_params_and_value(
5178 zero_payment_params, 100);
5179 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5180 &our_id, &route_params, &network_graph.read_only(), None,
5181 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5182 assert_eq!(err, "Can't find a route with no paths allowed.");
5183 } else { panic!(); }
5187 // Attempt to route while setting max_path_count to 3 results in a failure.
5188 // This is the case because the minimal_value_contribution_msat would require each path
5189 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5190 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5191 let route_params = RouteParameters::from_payment_params_and_value(
5192 fail_payment_params, 250_000);
5193 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5194 &our_id, &route_params, &network_graph.read_only(), None,
5195 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5196 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5197 } else { panic!(); }
5201 // Now, attempt to route 250 sats (just a bit below the capacity).
5202 // Our algorithm should provide us with these 3 paths.
5203 let route_params = RouteParameters::from_payment_params_and_value(
5204 payment_params.clone(), 250_000);
5205 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5206 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5207 assert_eq!(route.paths.len(), 3);
5208 let mut total_amount_paid_msat = 0;
5209 for path in &route.paths {
5210 if let Some(bt) = &path.blinded_tail {
5211 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5213 assert_eq!(path.hops.len(), 2);
5214 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5216 total_amount_paid_msat += path.final_value_msat();
5218 assert_eq!(total_amount_paid_msat, 250_000);
5222 // Attempt to route an exact amount is also fine
5223 let route_params = RouteParameters::from_payment_params_and_value(
5224 payment_params.clone(), 290_000);
5225 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5226 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5227 assert_eq!(route.paths.len(), 3);
5228 let mut total_amount_paid_msat = 0;
5229 for path in &route.paths {
5230 if payment_params.payee.blinded_route_hints().len() != 0 {
5231 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5232 if let Some(bt) = &path.blinded_tail {
5233 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5234 if bt.hops.len() > 1 {
5235 assert_eq!(path.hops.last().unwrap().pubkey,
5236 payment_params.payee.blinded_route_hints().iter()
5237 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5238 .map(|(_, p)| p.introduction_node_id).unwrap());
5240 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5243 assert_eq!(path.hops.len(), 2);
5244 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5246 total_amount_paid_msat += path.final_value_msat();
5248 assert_eq!(total_amount_paid_msat, 290_000);
5253 fn long_mpp_route_test() {
5254 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5255 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5256 let scorer = ln_test_utils::TestScorer::new();
5257 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5258 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5259 let config = UserConfig::default();
5260 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5261 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5264 // We need a route consisting of 3 paths:
5265 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5266 // Note that these paths overlap (channels 5, 12, 13).
5267 // We will route 300 sats.
5268 // Each path will have 100 sats capacity, those channels which
5269 // are used twice will have 200 sats capacity.
5271 // Disable other potential paths.
5272 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5273 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5274 short_channel_id: 2,
5277 cltv_expiry_delta: 0,
5278 htlc_minimum_msat: 0,
5279 htlc_maximum_msat: 100_000,
5281 fee_proportional_millionths: 0,
5282 excess_data: Vec::new()
5284 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5285 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5286 short_channel_id: 7,
5289 cltv_expiry_delta: 0,
5290 htlc_minimum_msat: 0,
5291 htlc_maximum_msat: 100_000,
5293 fee_proportional_millionths: 0,
5294 excess_data: Vec::new()
5297 // Path via {node0, node2} is channels {1, 3, 5}.
5298 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5299 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5300 short_channel_id: 1,
5303 cltv_expiry_delta: 0,
5304 htlc_minimum_msat: 0,
5305 htlc_maximum_msat: 100_000,
5307 fee_proportional_millionths: 0,
5308 excess_data: Vec::new()
5310 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5311 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5312 short_channel_id: 3,
5315 cltv_expiry_delta: 0,
5316 htlc_minimum_msat: 0,
5317 htlc_maximum_msat: 100_000,
5319 fee_proportional_millionths: 0,
5320 excess_data: Vec::new()
5323 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5324 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5325 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5326 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5327 short_channel_id: 5,
5330 cltv_expiry_delta: 0,
5331 htlc_minimum_msat: 0,
5332 htlc_maximum_msat: 200_000,
5334 fee_proportional_millionths: 0,
5335 excess_data: Vec::new()
5338 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5339 // Add 100 sats to the capacities of {12, 13}, because these channels
5340 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5341 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5342 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5343 short_channel_id: 12,
5346 cltv_expiry_delta: 0,
5347 htlc_minimum_msat: 0,
5348 htlc_maximum_msat: 200_000,
5350 fee_proportional_millionths: 0,
5351 excess_data: Vec::new()
5353 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5354 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5355 short_channel_id: 13,
5358 cltv_expiry_delta: 0,
5359 htlc_minimum_msat: 0,
5360 htlc_maximum_msat: 200_000,
5362 fee_proportional_millionths: 0,
5363 excess_data: Vec::new()
5366 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5367 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5368 short_channel_id: 6,
5371 cltv_expiry_delta: 0,
5372 htlc_minimum_msat: 0,
5373 htlc_maximum_msat: 100_000,
5375 fee_proportional_millionths: 0,
5376 excess_data: Vec::new()
5378 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5379 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5380 short_channel_id: 11,
5383 cltv_expiry_delta: 0,
5384 htlc_minimum_msat: 0,
5385 htlc_maximum_msat: 100_000,
5387 fee_proportional_millionths: 0,
5388 excess_data: Vec::new()
5391 // Path via {node7, node2} is channels {12, 13, 5}.
5392 // We already limited them to 200 sats (they are used twice for 100 sats).
5393 // Nothing to do here.
5396 // Attempt to route more than available results in a failure.
5397 let route_params = RouteParameters::from_payment_params_and_value(
5398 payment_params.clone(), 350_000);
5399 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5400 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5401 &scorer, &Default::default(), &random_seed_bytes) {
5402 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5403 } else { panic!(); }
5407 // Now, attempt to route 300 sats (exact amount we can route).
5408 // Our algorithm should provide us with these 3 paths, 100 sats each.
5409 let route_params = RouteParameters::from_payment_params_and_value(
5410 payment_params, 300_000);
5411 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5412 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5413 assert_eq!(route.paths.len(), 3);
5415 let mut total_amount_paid_msat = 0;
5416 for path in &route.paths {
5417 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5418 total_amount_paid_msat += path.final_value_msat();
5420 assert_eq!(total_amount_paid_msat, 300_000);
5426 fn mpp_cheaper_route_test() {
5427 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5428 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5429 let scorer = ln_test_utils::TestScorer::new();
5430 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5431 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5432 let config = UserConfig::default();
5433 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5434 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5437 // This test checks that if we have two cheaper paths and one more expensive path,
5438 // so that liquidity-wise any 2 of 3 combination is sufficient,
5439 // two cheaper paths will be taken.
5440 // These paths have equal available liquidity.
5442 // We need a combination of 3 paths:
5443 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5444 // Note that these paths overlap (channels 5, 12, 13).
5445 // Each path will have 100 sats capacity, those channels which
5446 // are used twice will have 200 sats capacity.
5448 // Disable other potential paths.
5449 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5450 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5451 short_channel_id: 2,
5454 cltv_expiry_delta: 0,
5455 htlc_minimum_msat: 0,
5456 htlc_maximum_msat: 100_000,
5458 fee_proportional_millionths: 0,
5459 excess_data: Vec::new()
5461 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5462 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5463 short_channel_id: 7,
5466 cltv_expiry_delta: 0,
5467 htlc_minimum_msat: 0,
5468 htlc_maximum_msat: 100_000,
5470 fee_proportional_millionths: 0,
5471 excess_data: Vec::new()
5474 // Path via {node0, node2} is channels {1, 3, 5}.
5475 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5476 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5477 short_channel_id: 1,
5480 cltv_expiry_delta: 0,
5481 htlc_minimum_msat: 0,
5482 htlc_maximum_msat: 100_000,
5484 fee_proportional_millionths: 0,
5485 excess_data: Vec::new()
5487 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5488 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5489 short_channel_id: 3,
5492 cltv_expiry_delta: 0,
5493 htlc_minimum_msat: 0,
5494 htlc_maximum_msat: 100_000,
5496 fee_proportional_millionths: 0,
5497 excess_data: Vec::new()
5500 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5501 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5502 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5503 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5504 short_channel_id: 5,
5507 cltv_expiry_delta: 0,
5508 htlc_minimum_msat: 0,
5509 htlc_maximum_msat: 200_000,
5511 fee_proportional_millionths: 0,
5512 excess_data: Vec::new()
5515 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5516 // Add 100 sats to the capacities of {12, 13}, because these channels
5517 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5518 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5519 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5520 short_channel_id: 12,
5523 cltv_expiry_delta: 0,
5524 htlc_minimum_msat: 0,
5525 htlc_maximum_msat: 200_000,
5527 fee_proportional_millionths: 0,
5528 excess_data: Vec::new()
5530 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5531 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5532 short_channel_id: 13,
5535 cltv_expiry_delta: 0,
5536 htlc_minimum_msat: 0,
5537 htlc_maximum_msat: 200_000,
5539 fee_proportional_millionths: 0,
5540 excess_data: Vec::new()
5543 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5544 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5545 short_channel_id: 6,
5548 cltv_expiry_delta: 0,
5549 htlc_minimum_msat: 0,
5550 htlc_maximum_msat: 100_000,
5551 fee_base_msat: 1_000,
5552 fee_proportional_millionths: 0,
5553 excess_data: Vec::new()
5555 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5556 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5557 short_channel_id: 11,
5560 cltv_expiry_delta: 0,
5561 htlc_minimum_msat: 0,
5562 htlc_maximum_msat: 100_000,
5564 fee_proportional_millionths: 0,
5565 excess_data: Vec::new()
5568 // Path via {node7, node2} is channels {12, 13, 5}.
5569 // We already limited them to 200 sats (they are used twice for 100 sats).
5570 // Nothing to do here.
5573 // Now, attempt to route 180 sats.
5574 // Our algorithm should provide us with these 2 paths.
5575 let route_params = RouteParameters::from_payment_params_and_value(
5576 payment_params, 180_000);
5577 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5578 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5579 assert_eq!(route.paths.len(), 2);
5581 let mut total_value_transferred_msat = 0;
5582 let mut total_paid_msat = 0;
5583 for path in &route.paths {
5584 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5585 total_value_transferred_msat += path.final_value_msat();
5586 for hop in &path.hops {
5587 total_paid_msat += hop.fee_msat;
5590 // If we paid fee, this would be higher.
5591 assert_eq!(total_value_transferred_msat, 180_000);
5592 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5593 assert_eq!(total_fees_paid, 0);
5598 fn fees_on_mpp_route_test() {
5599 // This test makes sure that MPP algorithm properly takes into account
5600 // fees charged on the channels, by making the fees impactful:
5601 // if the fee is not properly accounted for, the behavior is different.
5602 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5603 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5604 let scorer = ln_test_utils::TestScorer::new();
5605 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5606 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5607 let config = UserConfig::default();
5608 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5609 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5612 // We need a route consisting of 2 paths:
5613 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5614 // We will route 200 sats, Each path will have 100 sats capacity.
5616 // This test is not particularly stable: e.g.,
5617 // there's a way to route via {node0, node2, node4}.
5618 // It works while pathfinding is deterministic, but can be broken otherwise.
5619 // It's fine to ignore this concern for now.
5621 // Disable other potential paths.
5622 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5623 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5624 short_channel_id: 2,
5627 cltv_expiry_delta: 0,
5628 htlc_minimum_msat: 0,
5629 htlc_maximum_msat: 100_000,
5631 fee_proportional_millionths: 0,
5632 excess_data: Vec::new()
5635 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5636 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5637 short_channel_id: 7,
5640 cltv_expiry_delta: 0,
5641 htlc_minimum_msat: 0,
5642 htlc_maximum_msat: 100_000,
5644 fee_proportional_millionths: 0,
5645 excess_data: Vec::new()
5648 // Path via {node0, node2} is channels {1, 3, 5}.
5649 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5650 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5651 short_channel_id: 1,
5654 cltv_expiry_delta: 0,
5655 htlc_minimum_msat: 0,
5656 htlc_maximum_msat: 100_000,
5658 fee_proportional_millionths: 0,
5659 excess_data: Vec::new()
5661 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5662 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5663 short_channel_id: 3,
5666 cltv_expiry_delta: 0,
5667 htlc_minimum_msat: 0,
5668 htlc_maximum_msat: 100_000,
5670 fee_proportional_millionths: 0,
5671 excess_data: Vec::new()
5674 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5675 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5676 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5677 short_channel_id: 5,
5680 cltv_expiry_delta: 0,
5681 htlc_minimum_msat: 0,
5682 htlc_maximum_msat: 100_000,
5684 fee_proportional_millionths: 0,
5685 excess_data: Vec::new()
5688 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5689 // All channels should be 100 sats capacity. But for the fee experiment,
5690 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5691 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5692 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5693 // so no matter how large are other channels,
5694 // the whole path will be limited by 100 sats with just these 2 conditions:
5695 // - channel 12 capacity is 250 sats
5696 // - fee for channel 6 is 150 sats
5697 // Let's test this by enforcing these 2 conditions and removing other limits.
5698 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5699 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5700 short_channel_id: 12,
5703 cltv_expiry_delta: 0,
5704 htlc_minimum_msat: 0,
5705 htlc_maximum_msat: 250_000,
5707 fee_proportional_millionths: 0,
5708 excess_data: Vec::new()
5710 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5711 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5712 short_channel_id: 13,
5715 cltv_expiry_delta: 0,
5716 htlc_minimum_msat: 0,
5717 htlc_maximum_msat: MAX_VALUE_MSAT,
5719 fee_proportional_millionths: 0,
5720 excess_data: Vec::new()
5723 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5724 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5725 short_channel_id: 6,
5728 cltv_expiry_delta: 0,
5729 htlc_minimum_msat: 0,
5730 htlc_maximum_msat: MAX_VALUE_MSAT,
5731 fee_base_msat: 150_000,
5732 fee_proportional_millionths: 0,
5733 excess_data: Vec::new()
5735 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5736 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5737 short_channel_id: 11,
5740 cltv_expiry_delta: 0,
5741 htlc_minimum_msat: 0,
5742 htlc_maximum_msat: MAX_VALUE_MSAT,
5744 fee_proportional_millionths: 0,
5745 excess_data: Vec::new()
5749 // Attempt to route more than available results in a failure.
5750 let route_params = RouteParameters::from_payment_params_and_value(
5751 payment_params.clone(), 210_000);
5752 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5753 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5754 &scorer, &Default::default(), &random_seed_bytes) {
5755 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5756 } else { panic!(); }
5760 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5761 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5762 max_total_routing_fee_msat: Some(149_999) };
5763 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5764 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5765 &scorer, &Default::default(), &random_seed_bytes) {
5766 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5767 } else { panic!(); }
5771 // Now, attempt to route 200 sats (exact amount we can route).
5772 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5773 max_total_routing_fee_msat: Some(150_000) };
5774 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5775 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5776 assert_eq!(route.paths.len(), 2);
5778 let mut total_amount_paid_msat = 0;
5779 for path in &route.paths {
5780 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5781 total_amount_paid_msat += path.final_value_msat();
5783 assert_eq!(total_amount_paid_msat, 200_000);
5784 assert_eq!(route.get_total_fees(), 150_000);
5789 fn mpp_with_last_hops() {
5790 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5791 // via a single last-hop route hint, we'd fail to route if we first collected routes
5792 // totaling close but not quite enough to fund the full payment.
5794 // This was because we considered last-hop hints to have exactly the sought payment amount
5795 // instead of the amount we were trying to collect, needlessly limiting our path searching
5796 // at the very first hop.
5798 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5799 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5800 // to only have the remaining to-collect amount in available liquidity.
5802 // This bug appeared in production in some specific channel configurations.
5803 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5804 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5805 let scorer = ln_test_utils::TestScorer::new();
5806 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5807 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5808 let config = UserConfig::default();
5809 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
5810 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
5811 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5812 src_node_id: nodes[2],
5813 short_channel_id: 42,
5814 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5815 cltv_expiry_delta: 42,
5816 htlc_minimum_msat: None,
5817 htlc_maximum_msat: None,
5818 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5820 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5821 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5822 // would first use the no-fee route and then fail to find a path along the second route as
5823 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5824 // under 5% of our payment amount.
5825 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5826 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5827 short_channel_id: 1,
5830 cltv_expiry_delta: (5 << 4) | 5,
5831 htlc_minimum_msat: 0,
5832 htlc_maximum_msat: 99_000,
5833 fee_base_msat: u32::max_value(),
5834 fee_proportional_millionths: u32::max_value(),
5835 excess_data: Vec::new()
5837 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5838 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5839 short_channel_id: 2,
5842 cltv_expiry_delta: (5 << 4) | 3,
5843 htlc_minimum_msat: 0,
5844 htlc_maximum_msat: 99_000,
5845 fee_base_msat: u32::max_value(),
5846 fee_proportional_millionths: u32::max_value(),
5847 excess_data: Vec::new()
5849 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5850 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5851 short_channel_id: 4,
5854 cltv_expiry_delta: (4 << 4) | 1,
5855 htlc_minimum_msat: 0,
5856 htlc_maximum_msat: MAX_VALUE_MSAT,
5858 fee_proportional_millionths: 0,
5859 excess_data: Vec::new()
5861 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5862 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5863 short_channel_id: 13,
5865 flags: 0|2, // Channel disabled
5866 cltv_expiry_delta: (13 << 4) | 1,
5867 htlc_minimum_msat: 0,
5868 htlc_maximum_msat: MAX_VALUE_MSAT,
5870 fee_proportional_millionths: 2000000,
5871 excess_data: Vec::new()
5874 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5876 let route_params = RouteParameters::from_payment_params_and_value(
5877 payment_params, 100_000);
5878 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5879 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5880 assert_eq!(route.paths.len(), 2);
5881 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5882 // Paths are manually ordered ordered by SCID, so:
5883 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5884 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5885 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5886 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5887 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5888 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5889 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5890 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5891 assert_eq!(route.get_total_fees(), 1);
5892 assert_eq!(route.get_total_amount(), 100_000);
5896 fn drop_lowest_channel_mpp_route_test() {
5897 // This test checks that low-capacity channel is dropped when after
5898 // path finding we realize that we found more capacity than we need.
5899 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5900 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5901 let scorer = ln_test_utils::TestScorer::new();
5902 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5903 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5904 let config = UserConfig::default();
5905 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5906 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5908 .with_max_channel_saturation_power_of_half(0);
5910 // We need a route consisting of 3 paths:
5911 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5913 // The first and the second paths should be sufficient, but the third should be
5914 // cheaper, so that we select it but drop later.
5916 // First, we set limits on these (previously unlimited) channels.
5917 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5919 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5920 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5921 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5922 short_channel_id: 1,
5925 cltv_expiry_delta: 0,
5926 htlc_minimum_msat: 0,
5927 htlc_maximum_msat: 100_000,
5929 fee_proportional_millionths: 0,
5930 excess_data: Vec::new()
5932 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5933 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5934 short_channel_id: 3,
5937 cltv_expiry_delta: 0,
5938 htlc_minimum_msat: 0,
5939 htlc_maximum_msat: 50_000,
5941 fee_proportional_millionths: 0,
5942 excess_data: Vec::new()
5945 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5946 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5947 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5948 short_channel_id: 12,
5951 cltv_expiry_delta: 0,
5952 htlc_minimum_msat: 0,
5953 htlc_maximum_msat: 60_000,
5955 fee_proportional_millionths: 0,
5956 excess_data: Vec::new()
5958 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5959 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5960 short_channel_id: 13,
5963 cltv_expiry_delta: 0,
5964 htlc_minimum_msat: 0,
5965 htlc_maximum_msat: 60_000,
5967 fee_proportional_millionths: 0,
5968 excess_data: Vec::new()
5971 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5972 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5973 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5974 short_channel_id: 2,
5977 cltv_expiry_delta: 0,
5978 htlc_minimum_msat: 0,
5979 htlc_maximum_msat: 20_000,
5981 fee_proportional_millionths: 0,
5982 excess_data: Vec::new()
5984 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5985 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5986 short_channel_id: 4,
5989 cltv_expiry_delta: 0,
5990 htlc_minimum_msat: 0,
5991 htlc_maximum_msat: 20_000,
5993 fee_proportional_millionths: 0,
5994 excess_data: Vec::new()
5998 // Attempt to route more than available results in a failure.
5999 let route_params = RouteParameters::from_payment_params_and_value(
6000 payment_params.clone(), 150_000);
6001 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
6002 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
6003 &scorer, &Default::default(), &random_seed_bytes) {
6004 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6005 } else { panic!(); }
6009 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
6010 // Our algorithm should provide us with these 3 paths.
6011 let route_params = RouteParameters::from_payment_params_and_value(
6012 payment_params.clone(), 125_000);
6013 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6014 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6015 assert_eq!(route.paths.len(), 3);
6016 let mut total_amount_paid_msat = 0;
6017 for path in &route.paths {
6018 assert_eq!(path.hops.len(), 2);
6019 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6020 total_amount_paid_msat += path.final_value_msat();
6022 assert_eq!(total_amount_paid_msat, 125_000);
6026 // Attempt to route without the last small cheap channel
6027 let route_params = RouteParameters::from_payment_params_and_value(
6028 payment_params, 90_000);
6029 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6030 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6031 assert_eq!(route.paths.len(), 2);
6032 let mut total_amount_paid_msat = 0;
6033 for path in &route.paths {
6034 assert_eq!(path.hops.len(), 2);
6035 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6036 total_amount_paid_msat += path.final_value_msat();
6038 assert_eq!(total_amount_paid_msat, 90_000);
6043 fn min_criteria_consistency() {
6044 // Test that we don't use an inconsistent metric between updating and walking nodes during
6045 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
6046 // was updated with a different criterion from the heap sorting, resulting in loops in
6047 // calculated paths. We test for that specific case here.
6049 // We construct a network that looks like this:
6051 // node2 -1(3)2- node3
6055 // node1 -1(5)2- node4 -1(1)2- node6
6061 // We create a loop on the side of our real path - our destination is node 6, with a
6062 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
6063 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
6064 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
6065 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
6066 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
6067 // "previous hop" being set to node 3, creating a loop in the path.
6068 let secp_ctx = Secp256k1::new();
6069 let logger = Arc::new(ln_test_utils::TestLogger::new());
6070 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6071 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
6072 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6073 let scorer = ln_test_utils::TestScorer::new();
6074 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6075 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6076 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
6078 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
6079 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6080 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6081 short_channel_id: 6,
6084 cltv_expiry_delta: (6 << 4) | 0,
6085 htlc_minimum_msat: 0,
6086 htlc_maximum_msat: MAX_VALUE_MSAT,
6088 fee_proportional_millionths: 0,
6089 excess_data: Vec::new()
6091 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
6093 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
6094 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6095 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6096 short_channel_id: 5,
6099 cltv_expiry_delta: (5 << 4) | 0,
6100 htlc_minimum_msat: 0,
6101 htlc_maximum_msat: MAX_VALUE_MSAT,
6103 fee_proportional_millionths: 0,
6104 excess_data: Vec::new()
6106 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
6108 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
6109 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6110 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6111 short_channel_id: 4,
6114 cltv_expiry_delta: (4 << 4) | 0,
6115 htlc_minimum_msat: 0,
6116 htlc_maximum_msat: MAX_VALUE_MSAT,
6118 fee_proportional_millionths: 0,
6119 excess_data: Vec::new()
6121 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
6123 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
6124 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
6125 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6126 short_channel_id: 3,
6129 cltv_expiry_delta: (3 << 4) | 0,
6130 htlc_minimum_msat: 0,
6131 htlc_maximum_msat: MAX_VALUE_MSAT,
6133 fee_proportional_millionths: 0,
6134 excess_data: Vec::new()
6136 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
6138 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
6139 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
6140 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6141 short_channel_id: 2,
6144 cltv_expiry_delta: (2 << 4) | 0,
6145 htlc_minimum_msat: 0,
6146 htlc_maximum_msat: MAX_VALUE_MSAT,
6148 fee_proportional_millionths: 0,
6149 excess_data: Vec::new()
6152 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6153 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6154 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6155 short_channel_id: 1,
6158 cltv_expiry_delta: (1 << 4) | 0,
6159 htlc_minimum_msat: 100,
6160 htlc_maximum_msat: MAX_VALUE_MSAT,
6162 fee_proportional_millionths: 0,
6163 excess_data: Vec::new()
6165 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6168 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6169 let route_params = RouteParameters::from_payment_params_and_value(
6170 payment_params, 10_000);
6171 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6172 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6173 assert_eq!(route.paths.len(), 1);
6174 assert_eq!(route.paths[0].hops.len(), 3);
6176 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6177 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6178 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6179 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6180 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6181 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6183 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6184 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6185 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6186 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6187 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6188 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6190 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6191 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6192 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6193 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6194 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6195 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6201 fn exact_fee_liquidity_limit() {
6202 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6203 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6204 // we calculated fees on a higher value, resulting in us ignoring such paths.
6205 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6206 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6207 let scorer = ln_test_utils::TestScorer::new();
6208 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6209 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6210 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6212 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6214 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6215 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6216 short_channel_id: 2,
6219 cltv_expiry_delta: 0,
6220 htlc_minimum_msat: 0,
6221 htlc_maximum_msat: 85_000,
6223 fee_proportional_millionths: 0,
6224 excess_data: Vec::new()
6227 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6228 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6229 short_channel_id: 12,
6232 cltv_expiry_delta: (4 << 4) | 1,
6233 htlc_minimum_msat: 0,
6234 htlc_maximum_msat: 270_000,
6236 fee_proportional_millionths: 1000000,
6237 excess_data: Vec::new()
6241 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6242 // 200% fee charged channel 13 in the 1-to-2 direction.
6243 let mut route_params = RouteParameters::from_payment_params_and_value(
6244 payment_params, 90_000);
6245 route_params.max_total_routing_fee_msat = Some(90_000*2);
6246 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6247 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6248 assert_eq!(route.paths.len(), 1);
6249 assert_eq!(route.paths[0].hops.len(), 2);
6251 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6252 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6253 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6254 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6255 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6256 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6258 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6259 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6260 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6261 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6262 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6263 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6268 fn htlc_max_reduction_below_min() {
6269 // Test that if, while walking the graph, we reduce the value being sent to meet an
6270 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6271 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6272 // resulting in us thinking there is no possible path, even if other paths exist.
6273 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6274 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6275 let scorer = ln_test_utils::TestScorer::new();
6276 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6277 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6278 let config = UserConfig::default();
6279 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6280 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6283 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6284 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6285 // then try to send 90_000.
6286 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6287 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6288 short_channel_id: 2,
6291 cltv_expiry_delta: 0,
6292 htlc_minimum_msat: 0,
6293 htlc_maximum_msat: 80_000,
6295 fee_proportional_millionths: 0,
6296 excess_data: Vec::new()
6298 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6299 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6300 short_channel_id: 4,
6303 cltv_expiry_delta: (4 << 4) | 1,
6304 htlc_minimum_msat: 90_000,
6305 htlc_maximum_msat: MAX_VALUE_MSAT,
6307 fee_proportional_millionths: 0,
6308 excess_data: Vec::new()
6312 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6313 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6314 // expensive) channels 12-13 path.
6315 let mut route_params = RouteParameters::from_payment_params_and_value(
6316 payment_params, 90_000);
6317 route_params.max_total_routing_fee_msat = Some(90_000*2);
6318 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6319 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6320 assert_eq!(route.paths.len(), 1);
6321 assert_eq!(route.paths[0].hops.len(), 2);
6323 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6324 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6325 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6326 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6327 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6328 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6330 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6331 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6332 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6333 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6334 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6335 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6340 fn multiple_direct_first_hops() {
6341 // Previously we'd only ever considered one first hop path per counterparty.
6342 // However, as we don't restrict users to one channel per peer, we really need to support
6343 // looking at all first hop paths.
6344 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6345 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6346 // route over multiple channels with the same first hop.
6347 let secp_ctx = Secp256k1::new();
6348 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6349 let logger = Arc::new(ln_test_utils::TestLogger::new());
6350 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6351 let scorer = ln_test_utils::TestScorer::new();
6352 let config = UserConfig::default();
6353 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6354 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6356 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6357 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6360 let route_params = RouteParameters::from_payment_params_and_value(
6361 payment_params.clone(), 100_000);
6362 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6363 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6364 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6365 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6366 assert_eq!(route.paths.len(), 1);
6367 assert_eq!(route.paths[0].hops.len(), 1);
6369 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6370 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6371 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6374 let route_params = RouteParameters::from_payment_params_and_value(
6375 payment_params.clone(), 100_000);
6376 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6377 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6378 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6379 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6380 assert_eq!(route.paths.len(), 2);
6381 assert_eq!(route.paths[0].hops.len(), 1);
6382 assert_eq!(route.paths[1].hops.len(), 1);
6384 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6385 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6387 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6388 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6390 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6391 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6395 // If we have a bunch of outbound channels to the same node, where most are not
6396 // sufficient to pay the full payment, but one is, we should default to just using the
6397 // one single channel that has sufficient balance, avoiding MPP.
6399 // If we have several options above the 3xpayment value threshold, we should pick the
6400 // smallest of them, avoiding further fragmenting our available outbound balance to
6402 let route_params = RouteParameters::from_payment_params_and_value(
6403 payment_params, 100_000);
6404 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6405 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6406 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6407 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6408 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6409 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6410 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6411 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6412 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6413 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6414 assert_eq!(route.paths.len(), 1);
6415 assert_eq!(route.paths[0].hops.len(), 1);
6417 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6418 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6419 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6424 fn prefers_shorter_route_with_higher_fees() {
6425 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6426 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6427 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6429 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6430 let scorer = ln_test_utils::TestScorer::new();
6431 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6432 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6433 let route_params = RouteParameters::from_payment_params_and_value(
6434 payment_params.clone(), 100);
6435 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6436 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6437 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6439 assert_eq!(route.get_total_fees(), 100);
6440 assert_eq!(route.get_total_amount(), 100);
6441 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6443 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6444 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6445 let scorer = FixedPenaltyScorer::with_penalty(100);
6446 let route_params = RouteParameters::from_payment_params_and_value(
6447 payment_params, 100);
6448 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6449 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6450 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6452 assert_eq!(route.get_total_fees(), 300);
6453 assert_eq!(route.get_total_amount(), 100);
6454 assert_eq!(path, vec![2, 4, 7, 10]);
6457 struct BadChannelScorer {
6458 short_channel_id: u64,
6462 impl Writeable for BadChannelScorer {
6463 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6465 impl ScoreLookUp for BadChannelScorer {
6466 type ScoreParams = ();
6467 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6468 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6472 struct BadNodeScorer {
6477 impl Writeable for BadNodeScorer {
6478 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6481 impl ScoreLookUp for BadNodeScorer {
6482 type ScoreParams = ();
6483 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6484 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6489 fn avoids_routing_through_bad_channels_and_nodes() {
6490 let (secp_ctx, network, _, _, logger) = build_graph();
6491 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6492 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6493 let network_graph = network.read_only();
6495 // A path to nodes[6] exists when no penalties are applied to any channel.
6496 let scorer = ln_test_utils::TestScorer::new();
6497 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6498 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6499 let route_params = RouteParameters::from_payment_params_and_value(
6500 payment_params, 100);
6501 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6502 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6503 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6505 assert_eq!(route.get_total_fees(), 100);
6506 assert_eq!(route.get_total_amount(), 100);
6507 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6509 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6510 let scorer = BadChannelScorer { short_channel_id: 6 };
6511 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6512 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6513 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6515 assert_eq!(route.get_total_fees(), 300);
6516 assert_eq!(route.get_total_amount(), 100);
6517 assert_eq!(path, vec![2, 4, 7, 10]);
6519 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6520 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6521 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6522 &scorer, &Default::default(), &random_seed_bytes) {
6523 Err(LightningError { err, .. } ) => {
6524 assert_eq!(err, "Failed to find a path to the given destination");
6526 Ok(_) => panic!("Expected error"),
6531 fn total_fees_single_path() {
6533 paths: vec![Path { hops: vec![
6535 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6536 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6537 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6540 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6541 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6542 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6545 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6546 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6547 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6549 ], blinded_tail: None }],
6553 assert_eq!(route.get_total_fees(), 250);
6554 assert_eq!(route.get_total_amount(), 225);
6558 fn total_fees_multi_path() {
6560 paths: vec![Path { hops: vec![
6562 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6563 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6564 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6567 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6568 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6569 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6571 ], blinded_tail: None }, Path { hops: vec![
6573 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6574 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6575 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6578 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6579 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6580 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6582 ], blinded_tail: None }],
6586 assert_eq!(route.get_total_fees(), 200);
6587 assert_eq!(route.get_total_amount(), 300);
6591 fn total_empty_route_no_panic() {
6592 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6593 // would both panic if the route was completely empty. We test to ensure they return 0
6594 // here, even though its somewhat nonsensical as a route.
6595 let route = Route { paths: Vec::new(), route_params: None };
6597 assert_eq!(route.get_total_fees(), 0);
6598 assert_eq!(route.get_total_amount(), 0);
6602 fn limits_total_cltv_delta() {
6603 let (secp_ctx, network, _, _, logger) = build_graph();
6604 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6605 let network_graph = network.read_only();
6607 let scorer = ln_test_utils::TestScorer::new();
6609 // Make sure that generally there is at least one route available
6610 let feasible_max_total_cltv_delta = 1008;
6611 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6612 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6613 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6614 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6615 let route_params = RouteParameters::from_payment_params_and_value(
6616 feasible_payment_params, 100);
6617 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6618 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6619 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6620 assert_ne!(path.len(), 0);
6622 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6623 let fail_max_total_cltv_delta = 23;
6624 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6625 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6626 let route_params = RouteParameters::from_payment_params_and_value(
6627 fail_payment_params, 100);
6628 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6629 &Default::default(), &random_seed_bytes)
6631 Err(LightningError { err, .. } ) => {
6632 assert_eq!(err, "Failed to find a path to the given destination");
6634 Ok(_) => panic!("Expected error"),
6639 fn avoids_recently_failed_paths() {
6640 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6641 // randomly inserting channels into it until we can't find a route anymore.
6642 let (secp_ctx, network, _, _, logger) = build_graph();
6643 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6644 let network_graph = network.read_only();
6646 let scorer = ln_test_utils::TestScorer::new();
6647 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6648 .with_max_path_count(1);
6649 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6650 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6652 // We should be able to find a route initially, and then after we fail a few random
6653 // channels eventually we won't be able to any longer.
6654 let route_params = RouteParameters::from_payment_params_and_value(
6655 payment_params.clone(), 100);
6656 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6657 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6659 let route_params = RouteParameters::from_payment_params_and_value(
6660 payment_params.clone(), 100);
6661 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6662 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6664 for chan in route.paths[0].hops.iter() {
6665 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6667 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6668 % route.paths[0].hops.len();
6669 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6675 fn limits_path_length() {
6676 let (secp_ctx, network, _, _, logger) = build_line_graph();
6677 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6678 let network_graph = network.read_only();
6680 let scorer = ln_test_utils::TestScorer::new();
6681 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6682 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6684 // First check we can actually create a long route on this graph.
6685 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6686 let route_params = RouteParameters::from_payment_params_and_value(
6687 feasible_payment_params, 100);
6688 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6689 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6690 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6691 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6693 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6694 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6695 let route_params = RouteParameters::from_payment_params_and_value(
6696 fail_payment_params, 100);
6697 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6698 &Default::default(), &random_seed_bytes)
6700 Err(LightningError { err, .. } ) => {
6701 assert_eq!(err, "Failed to find a path to the given destination");
6703 Ok(_) => panic!("Expected error"),
6708 fn adds_and_limits_cltv_offset() {
6709 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6710 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6712 let scorer = ln_test_utils::TestScorer::new();
6714 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6715 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6716 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6717 let route_params = RouteParameters::from_payment_params_and_value(
6718 payment_params.clone(), 100);
6719 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6720 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6721 assert_eq!(route.paths.len(), 1);
6723 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6725 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6726 let mut route_default = route.clone();
6727 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6728 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6729 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6730 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6731 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6733 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6734 let mut route_limited = route.clone();
6735 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6736 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6737 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6738 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6739 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6743 fn adds_plausible_cltv_offset() {
6744 let (secp_ctx, network, _, _, logger) = build_graph();
6745 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6746 let network_graph = network.read_only();
6747 let network_nodes = network_graph.nodes();
6748 let network_channels = network_graph.channels();
6749 let scorer = ln_test_utils::TestScorer::new();
6750 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6751 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6752 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6754 let route_params = RouteParameters::from_payment_params_and_value(
6755 payment_params.clone(), 100);
6756 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6757 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6758 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6760 let mut path_plausibility = vec![];
6762 for p in route.paths {
6763 // 1. Select random observation point
6764 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6765 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6767 prng.process_in_place(&mut random_bytes);
6768 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6769 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6771 // 2. Calculate what CLTV expiry delta we would observe there
6772 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6774 // 3. Starting from the observation point, find candidate paths
6775 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6776 candidates.push_back((observation_point, vec![]));
6778 let mut found_plausible_candidate = false;
6780 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6781 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6782 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6783 found_plausible_candidate = true;
6784 break 'candidate_loop;
6788 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6789 for channel_id in &cur_node.channels {
6790 if let Some(channel_info) = network_channels.get(&channel_id) {
6791 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6792 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6793 if cur_path_cltv_deltas.iter().sum::<u32>()
6794 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6795 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6796 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6797 candidates.push_back((*next_id, new_path_cltv_deltas));
6805 path_plausibility.push(found_plausible_candidate);
6807 assert!(path_plausibility.iter().all(|x| *x));
6811 fn builds_correct_path_from_hops() {
6812 let (secp_ctx, network, _, _, logger) = build_graph();
6813 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6814 let network_graph = network.read_only();
6816 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6817 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6819 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6820 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6821 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6822 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6823 Arc::clone(&logger), &random_seed_bytes).unwrap();
6824 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6825 assert_eq!(hops.len(), route.paths[0].hops.len());
6826 for (idx, hop_pubkey) in hops.iter().enumerate() {
6827 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6832 fn avoids_saturating_channels() {
6833 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6834 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6835 let decay_params = ProbabilisticScoringDecayParameters::default();
6836 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6838 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6839 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6840 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6841 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6842 short_channel_id: 4,
6845 cltv_expiry_delta: (4 << 4) | 1,
6846 htlc_minimum_msat: 0,
6847 htlc_maximum_msat: 250_000_000,
6849 fee_proportional_millionths: 0,
6850 excess_data: Vec::new()
6852 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6853 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6854 short_channel_id: 13,
6857 cltv_expiry_delta: (13 << 4) | 1,
6858 htlc_minimum_msat: 0,
6859 htlc_maximum_msat: 250_000_000,
6861 fee_proportional_millionths: 0,
6862 excess_data: Vec::new()
6865 let config = UserConfig::default();
6866 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6867 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6869 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6870 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6871 // 100,000 sats is less than the available liquidity on each channel, set above.
6872 let route_params = RouteParameters::from_payment_params_and_value(
6873 payment_params, 100_000_000);
6874 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6875 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6876 assert_eq!(route.paths.len(), 2);
6877 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6878 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6881 #[cfg(not(feature = "no-std"))]
6882 pub(super) fn random_init_seed() -> u64 {
6883 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6884 use core::hash::{BuildHasher, Hasher};
6885 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6886 println!("Using seed of {}", seed);
6891 #[cfg(not(feature = "no-std"))]
6892 fn generate_routes() {
6893 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6895 let logger = ln_test_utils::TestLogger::new();
6896 let graph = match super::bench_utils::read_network_graph(&logger) {
6904 let params = ProbabilisticScoringFeeParameters::default();
6905 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6906 let features = super::Bolt11InvoiceFeatures::empty();
6908 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6912 #[cfg(not(feature = "no-std"))]
6913 fn generate_routes_mpp() {
6914 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6916 let logger = ln_test_utils::TestLogger::new();
6917 let graph = match super::bench_utils::read_network_graph(&logger) {
6925 let params = ProbabilisticScoringFeeParameters::default();
6926 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6927 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6929 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6933 #[cfg(not(feature = "no-std"))]
6934 fn generate_large_mpp_routes() {
6935 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6937 let logger = ln_test_utils::TestLogger::new();
6938 let graph = match super::bench_utils::read_network_graph(&logger) {
6946 let params = ProbabilisticScoringFeeParameters::default();
6947 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6948 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6950 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6954 fn honors_manual_penalties() {
6955 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6956 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6958 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6959 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6961 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6962 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6964 // First check set manual penalties are returned by the scorer.
6965 let usage = ChannelUsage {
6967 inflight_htlc_msat: 0,
6968 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6970 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6971 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6972 let network_graph = network_graph.read_only();
6973 let channels = network_graph.channels();
6974 let channel = channels.get(&5).unwrap();
6975 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
6976 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop {
6978 short_channel_id: 5,
6980 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
6982 // Then check we can get a normal route
6983 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6984 let route_params = RouteParameters::from_payment_params_and_value(
6985 payment_params, 100);
6986 let route = get_route(&our_id, &route_params, &network_graph, None,
6987 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6988 assert!(route.is_ok());
6990 // Then check that we can't get a route if we ban an intermediate node.
6991 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6992 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6993 assert!(route.is_err());
6995 // Finally make sure we can route again, when we remove the ban.
6996 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6997 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6998 assert!(route.is_ok());
7002 fn abide_by_route_hint_max_htlc() {
7003 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
7004 // params in the final route.
7005 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7006 let netgraph = network_graph.read_only();
7007 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7008 let scorer = ln_test_utils::TestScorer::new();
7009 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7010 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7011 let config = UserConfig::default();
7013 let max_htlc_msat = 50_000;
7014 let route_hint_1 = RouteHint(vec![RouteHintHop {
7015 src_node_id: nodes[2],
7016 short_channel_id: 42,
7019 proportional_millionths: 0,
7021 cltv_expiry_delta: 10,
7022 htlc_minimum_msat: None,
7023 htlc_maximum_msat: Some(max_htlc_msat),
7025 let dest_node_id = ln_test_utils::pubkey(42);
7026 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7027 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
7028 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7031 // Make sure we'll error if our route hints don't have enough liquidity according to their
7032 // htlc_maximum_msat.
7033 let mut route_params = RouteParameters::from_payment_params_and_value(
7034 payment_params, max_htlc_msat + 1);
7035 route_params.max_total_routing_fee_msat = None;
7036 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
7037 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
7040 assert_eq!(err, "Failed to find a sufficient route to the given destination");
7041 } else { panic!(); }
7043 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
7044 let mut route_hint_2 = route_hint_1.clone();
7045 route_hint_2.0[0].short_channel_id = 43;
7046 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7047 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7048 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7050 let mut route_params = RouteParameters::from_payment_params_and_value(
7051 payment_params, max_htlc_msat + 1);
7052 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
7053 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
7054 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7055 assert_eq!(route.paths.len(), 2);
7056 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7057 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7061 fn direct_channel_to_hints_with_max_htlc() {
7062 // Check that if we have a first hop channel peer that's connected to multiple provided route
7063 // hints, that we properly split the payment between the route hints if needed.
7064 let logger = Arc::new(ln_test_utils::TestLogger::new());
7065 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7066 let scorer = ln_test_utils::TestScorer::new();
7067 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7068 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7069 let config = UserConfig::default();
7071 let our_node_id = ln_test_utils::pubkey(42);
7072 let intermed_node_id = ln_test_utils::pubkey(43);
7073 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7075 let amt_msat = 900_000;
7076 let max_htlc_msat = 500_000;
7077 let route_hint_1 = RouteHint(vec![RouteHintHop {
7078 src_node_id: intermed_node_id,
7079 short_channel_id: 44,
7082 proportional_millionths: 0,
7084 cltv_expiry_delta: 10,
7085 htlc_minimum_msat: None,
7086 htlc_maximum_msat: Some(max_htlc_msat),
7088 src_node_id: intermed_node_id,
7089 short_channel_id: 45,
7092 proportional_millionths: 0,
7094 cltv_expiry_delta: 10,
7095 htlc_minimum_msat: None,
7096 // Check that later route hint max htlcs don't override earlier ones
7097 htlc_maximum_msat: Some(max_htlc_msat - 50),
7099 let mut route_hint_2 = route_hint_1.clone();
7100 route_hint_2.0[0].short_channel_id = 46;
7101 route_hint_2.0[1].short_channel_id = 47;
7102 let dest_node_id = ln_test_utils::pubkey(44);
7103 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7104 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7105 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7108 let route_params = RouteParameters::from_payment_params_and_value(
7109 payment_params, amt_msat);
7110 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7111 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7112 &Default::default(), &random_seed_bytes).unwrap();
7113 assert_eq!(route.paths.len(), 2);
7114 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7115 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7116 assert_eq!(route.get_total_amount(), amt_msat);
7118 // Re-run but with two first hop channels connected to the same route hint peers that must be
7120 let first_hops = vec![
7121 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7122 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7124 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7125 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7126 &Default::default(), &random_seed_bytes).unwrap();
7127 assert_eq!(route.paths.len(), 2);
7128 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7129 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7130 assert_eq!(route.get_total_amount(), amt_msat);
7132 // Make sure this works for blinded route hints.
7133 let blinded_path = BlindedPath {
7134 introduction_node_id: intermed_node_id,
7135 blinding_point: ln_test_utils::pubkey(42),
7137 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
7138 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
7141 let blinded_payinfo = BlindedPayInfo {
7143 fee_proportional_millionths: 0,
7144 htlc_minimum_msat: 1,
7145 htlc_maximum_msat: max_htlc_msat,
7146 cltv_expiry_delta: 10,
7147 features: BlindedHopFeatures::empty(),
7149 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7150 let payment_params = PaymentParameters::blinded(vec![
7151 (blinded_payinfo.clone(), blinded_path.clone()),
7152 (blinded_payinfo.clone(), blinded_path.clone())])
7153 .with_bolt12_features(bolt12_features).unwrap();
7154 let route_params = RouteParameters::from_payment_params_and_value(
7155 payment_params, amt_msat);
7156 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7157 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7158 &Default::default(), &random_seed_bytes).unwrap();
7159 assert_eq!(route.paths.len(), 2);
7160 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7161 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7162 assert_eq!(route.get_total_amount(), amt_msat);
7166 fn blinded_route_ser() {
7167 let blinded_path_1 = BlindedPath {
7168 introduction_node_id: ln_test_utils::pubkey(42),
7169 blinding_point: ln_test_utils::pubkey(43),
7171 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7172 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7175 let blinded_path_2 = BlindedPath {
7176 introduction_node_id: ln_test_utils::pubkey(46),
7177 blinding_point: ln_test_utils::pubkey(47),
7179 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7180 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7183 // (De)serialize a Route with 1 blinded path out of two total paths.
7184 let mut route = Route { paths: vec![Path {
7185 hops: vec![RouteHop {
7186 pubkey: ln_test_utils::pubkey(50),
7187 node_features: NodeFeatures::empty(),
7188 short_channel_id: 42,
7189 channel_features: ChannelFeatures::empty(),
7191 cltv_expiry_delta: 0,
7192 maybe_announced_channel: true,
7194 blinded_tail: Some(BlindedTail {
7195 hops: blinded_path_1.blinded_hops,
7196 blinding_point: blinded_path_1.blinding_point,
7197 excess_final_cltv_expiry_delta: 40,
7198 final_value_msat: 100,
7200 hops: vec![RouteHop {
7201 pubkey: ln_test_utils::pubkey(51),
7202 node_features: NodeFeatures::empty(),
7203 short_channel_id: 43,
7204 channel_features: ChannelFeatures::empty(),
7206 cltv_expiry_delta: 0,
7207 maybe_announced_channel: true,
7208 }], blinded_tail: None }],
7211 let encoded_route = route.encode();
7212 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7213 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7214 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7216 // (De)serialize a Route with two paths, each containing a blinded tail.
7217 route.paths[1].blinded_tail = Some(BlindedTail {
7218 hops: blinded_path_2.blinded_hops,
7219 blinding_point: blinded_path_2.blinding_point,
7220 excess_final_cltv_expiry_delta: 41,
7221 final_value_msat: 101,
7223 let encoded_route = route.encode();
7224 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7225 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7226 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7230 fn blinded_path_inflight_processing() {
7231 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7232 // account for the blinded tail's final amount_msat.
7233 let mut inflight_htlcs = InFlightHtlcs::new();
7234 let blinded_path = BlindedPath {
7235 introduction_node_id: ln_test_utils::pubkey(43),
7236 blinding_point: ln_test_utils::pubkey(48),
7237 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7240 hops: vec![RouteHop {
7241 pubkey: ln_test_utils::pubkey(42),
7242 node_features: NodeFeatures::empty(),
7243 short_channel_id: 42,
7244 channel_features: ChannelFeatures::empty(),
7246 cltv_expiry_delta: 0,
7247 maybe_announced_channel: false,
7250 pubkey: blinded_path.introduction_node_id,
7251 node_features: NodeFeatures::empty(),
7252 short_channel_id: 43,
7253 channel_features: ChannelFeatures::empty(),
7255 cltv_expiry_delta: 0,
7256 maybe_announced_channel: false,
7258 blinded_tail: Some(BlindedTail {
7259 hops: blinded_path.blinded_hops,
7260 blinding_point: blinded_path.blinding_point,
7261 excess_final_cltv_expiry_delta: 0,
7262 final_value_msat: 200,
7265 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7266 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7267 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7271 fn blinded_path_cltv_shadow_offset() {
7272 // Make sure we add a shadow offset when sending to blinded paths.
7273 let blinded_path = BlindedPath {
7274 introduction_node_id: ln_test_utils::pubkey(43),
7275 blinding_point: ln_test_utils::pubkey(44),
7277 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7278 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7281 let mut route = Route { paths: vec![Path {
7282 hops: vec![RouteHop {
7283 pubkey: ln_test_utils::pubkey(42),
7284 node_features: NodeFeatures::empty(),
7285 short_channel_id: 42,
7286 channel_features: ChannelFeatures::empty(),
7288 cltv_expiry_delta: 0,
7289 maybe_announced_channel: false,
7292 pubkey: blinded_path.introduction_node_id,
7293 node_features: NodeFeatures::empty(),
7294 short_channel_id: 43,
7295 channel_features: ChannelFeatures::empty(),
7297 cltv_expiry_delta: 0,
7298 maybe_announced_channel: false,
7301 blinded_tail: Some(BlindedTail {
7302 hops: blinded_path.blinded_hops,
7303 blinding_point: blinded_path.blinding_point,
7304 excess_final_cltv_expiry_delta: 0,
7305 final_value_msat: 200,
7307 }], route_params: None};
7309 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7310 let (_, network_graph, _, _, _) = build_line_graph();
7311 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7312 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7313 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7317 fn simple_blinded_route_hints() {
7318 do_simple_blinded_route_hints(1);
7319 do_simple_blinded_route_hints(2);
7320 do_simple_blinded_route_hints(3);
7323 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7324 // Check that we can generate a route to a blinded path with the expected hops.
7325 let (secp_ctx, network, _, _, logger) = build_graph();
7326 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7327 let network_graph = network.read_only();
7329 let scorer = ln_test_utils::TestScorer::new();
7330 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7331 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7333 let mut blinded_path = BlindedPath {
7334 introduction_node_id: nodes[2],
7335 blinding_point: ln_test_utils::pubkey(42),
7336 blinded_hops: Vec::with_capacity(num_blinded_hops),
7338 for i in 0..num_blinded_hops {
7339 blinded_path.blinded_hops.push(
7340 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7343 let blinded_payinfo = BlindedPayInfo {
7345 fee_proportional_millionths: 500,
7346 htlc_minimum_msat: 1000,
7347 htlc_maximum_msat: 100_000_000,
7348 cltv_expiry_delta: 15,
7349 features: BlindedHopFeatures::empty(),
7352 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7353 let route_params = RouteParameters::from_payment_params_and_value(
7354 payment_params, 1001);
7355 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7356 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7357 assert_eq!(route.paths.len(), 1);
7358 assert_eq!(route.paths[0].hops.len(), 2);
7360 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7361 assert_eq!(tail.hops, blinded_path.blinded_hops);
7362 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7363 assert_eq!(tail.final_value_msat, 1001);
7365 let final_hop = route.paths[0].hops.last().unwrap();
7366 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
7367 if tail.hops.len() > 1 {
7368 assert_eq!(final_hop.fee_msat,
7369 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7370 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7372 assert_eq!(final_hop.fee_msat, 0);
7373 assert_eq!(final_hop.cltv_expiry_delta, 0);
7378 fn blinded_path_routing_errors() {
7379 // Check that we can generate a route to a blinded path with the expected hops.
7380 let (secp_ctx, network, _, _, logger) = build_graph();
7381 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7382 let network_graph = network.read_only();
7384 let scorer = ln_test_utils::TestScorer::new();
7385 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7386 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7388 let mut invalid_blinded_path = BlindedPath {
7389 introduction_node_id: nodes[2],
7390 blinding_point: ln_test_utils::pubkey(42),
7392 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7395 let blinded_payinfo = BlindedPayInfo {
7397 fee_proportional_millionths: 500,
7398 htlc_minimum_msat: 1000,
7399 htlc_maximum_msat: 100_000_000,
7400 cltv_expiry_delta: 15,
7401 features: BlindedHopFeatures::empty(),
7404 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7405 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7406 let payment_params = PaymentParameters::blinded(vec![
7407 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7408 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7409 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7410 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7411 &scorer, &Default::default(), &random_seed_bytes)
7413 Err(LightningError { err, .. }) => {
7414 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7416 _ => panic!("Expected error")
7419 invalid_blinded_path.introduction_node_id = our_id;
7420 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7421 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7422 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7423 &Default::default(), &random_seed_bytes)
7425 Err(LightningError { err, .. }) => {
7426 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7428 _ => panic!("Expected error")
7431 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7432 invalid_blinded_path.blinded_hops.clear();
7433 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7434 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7435 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7436 &Default::default(), &random_seed_bytes)
7438 Err(LightningError { err, .. }) => {
7439 assert_eq!(err, "0-hop blinded path provided");
7441 _ => panic!("Expected error")
7446 fn matching_intro_node_paths_provided() {
7447 // Check that if multiple blinded paths with the same intro node are provided in payment
7448 // parameters, we'll return the correct paths in the resulting MPP route.
7449 let (secp_ctx, network, _, _, logger) = build_graph();
7450 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7451 let network_graph = network.read_only();
7453 let scorer = ln_test_utils::TestScorer::new();
7454 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7455 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7456 let config = UserConfig::default();
7458 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7459 let blinded_path_1 = BlindedPath {
7460 introduction_node_id: nodes[2],
7461 blinding_point: ln_test_utils::pubkey(42),
7463 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7464 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7467 let blinded_payinfo_1 = BlindedPayInfo {
7469 fee_proportional_millionths: 0,
7470 htlc_minimum_msat: 0,
7471 htlc_maximum_msat: 30_000,
7472 cltv_expiry_delta: 0,
7473 features: BlindedHopFeatures::empty(),
7476 let mut blinded_path_2 = blinded_path_1.clone();
7477 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7478 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7479 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7481 let blinded_hints = vec![
7482 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7483 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7485 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7486 .with_bolt12_features(bolt12_features).unwrap();
7488 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7489 route_params.max_total_routing_fee_msat = Some(100_000);
7490 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7491 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7492 assert_eq!(route.paths.len(), 2);
7493 let mut total_amount_paid_msat = 0;
7494 for path in route.paths.into_iter() {
7495 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7496 if let Some(bt) = &path.blinded_tail {
7497 assert_eq!(bt.blinding_point,
7498 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7499 .map(|(_, bp)| bp.blinding_point).unwrap());
7500 } else { panic!(); }
7501 total_amount_paid_msat += path.final_value_msat();
7503 assert_eq!(total_amount_paid_msat, 100_000);
7507 fn direct_to_intro_node() {
7508 // This previously caused a debug panic in the router when asserting
7509 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7510 // direct channels we failed to account for the fee charged for use of the blinded path.
7513 // node0 -1(1)2 - node1
7514 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7515 // doesn't account for the blinded path fee.
7517 let secp_ctx = Secp256k1::new();
7518 let logger = Arc::new(ln_test_utils::TestLogger::new());
7519 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7520 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7521 let scorer = ln_test_utils::TestScorer::new();
7522 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7523 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7525 let amt_msat = 10_000_000;
7526 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7527 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7528 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7529 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7530 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7531 short_channel_id: 1,
7534 cltv_expiry_delta: 42,
7535 htlc_minimum_msat: 1_000,
7536 htlc_maximum_msat: 10_000_000,
7538 fee_proportional_millionths: 0,
7539 excess_data: Vec::new()
7541 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7542 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7543 short_channel_id: 1,
7546 cltv_expiry_delta: 42,
7547 htlc_minimum_msat: 1_000,
7548 htlc_maximum_msat: 10_000_000,
7550 fee_proportional_millionths: 0,
7551 excess_data: Vec::new()
7553 let first_hops = vec![
7554 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7556 let blinded_path = BlindedPath {
7557 introduction_node_id: nodes[1],
7558 blinding_point: ln_test_utils::pubkey(42),
7560 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7561 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7564 let blinded_payinfo = BlindedPayInfo {
7565 fee_base_msat: 1000,
7566 fee_proportional_millionths: 0,
7567 htlc_minimum_msat: 1000,
7568 htlc_maximum_msat: MAX_VALUE_MSAT,
7569 cltv_expiry_delta: 0,
7570 features: BlindedHopFeatures::empty(),
7572 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7574 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7576 let netgraph = network_graph.read_only();
7577 let route_params = RouteParameters::from_payment_params_and_value(
7578 payment_params.clone(), amt_msat);
7579 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7580 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7581 &Default::default(), &random_seed_bytes) {
7582 assert_eq!(err, "Failed to find a path to the given destination");
7583 } else { panic!("Expected error") }
7585 // Sending an exact amount accounting for the blinded path fee works.
7586 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7587 let route_params = RouteParameters::from_payment_params_and_value(
7588 payment_params, amt_minus_blinded_path_fee);
7589 let route = get_route(&nodes[0], &route_params, &netgraph,
7590 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7591 &Default::default(), &random_seed_bytes).unwrap();
7592 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7593 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7597 fn direct_to_matching_intro_nodes() {
7598 // This previously caused us to enter `unreachable` code in the following situation:
7599 // 1. We add a route candidate for intro_node contributing a high amount
7600 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7601 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7602 // amount, and update our route candidate for intro_node for the lower amount
7603 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7604 // lower contribution amount, but fail (this was previously caused by failure to account for
7605 // blinded path fees when adding first_hop<>intro_node candidates)
7606 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7607 // candidate still thinks its path is contributing the original higher amount. This caused us
7608 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7610 let secp_ctx = Secp256k1::new();
7611 let logger = Arc::new(ln_test_utils::TestLogger::new());
7612 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7613 let scorer = ln_test_utils::TestScorer::new();
7614 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7615 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7616 let config = UserConfig::default();
7618 // Values are taken from the fuzz input that uncovered this panic.
7619 let amt_msat = 21_7020_5185_1403_2640;
7620 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7621 let first_hops = vec![
7622 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7623 18446744073709551615)];
7625 let blinded_path = BlindedPath {
7626 introduction_node_id: nodes[1],
7627 blinding_point: ln_test_utils::pubkey(42),
7629 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7630 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7633 let blinded_payinfo = BlindedPayInfo {
7634 fee_base_msat: 5046_2720,
7635 fee_proportional_millionths: 0,
7636 htlc_minimum_msat: 4503_5996_2737_0496,
7637 htlc_maximum_msat: 45_0359_9627_3704_9600,
7638 cltv_expiry_delta: 0,
7639 features: BlindedHopFeatures::empty(),
7641 let mut blinded_hints = vec![
7642 (blinded_payinfo.clone(), blinded_path.clone()),
7643 (blinded_payinfo.clone(), blinded_path.clone()),
7645 blinded_hints[1].0.fee_base_msat = 419_4304;
7646 blinded_hints[1].0.fee_proportional_millionths = 257;
7647 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7648 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7649 blinded_hints[1].0.cltv_expiry_delta = 0;
7651 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7652 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7653 .with_bolt12_features(bolt12_features).unwrap();
7655 let netgraph = network_graph.read_only();
7656 let route_params = RouteParameters::from_payment_params_and_value(
7657 payment_params, amt_msat);
7658 let route = get_route(&nodes[0], &route_params, &netgraph,
7659 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7660 &Default::default(), &random_seed_bytes).unwrap();
7661 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7662 assert_eq!(route.get_total_amount(), amt_msat);
7666 fn we_are_intro_node_candidate_hops() {
7667 // This previously led to a panic in the router because we'd generate a Path with only a
7668 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7669 // where the origin node is the intro node. We now fully disallow considering candidate hops
7670 // where the origin node is the intro node.
7671 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7672 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7673 let scorer = ln_test_utils::TestScorer::new();
7674 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7675 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7676 let config = UserConfig::default();
7678 // Values are taken from the fuzz input that uncovered this panic.
7679 let amt_msat = 21_7020_5185_1423_0019;
7681 let blinded_path = BlindedPath {
7682 introduction_node_id: our_id,
7683 blinding_point: ln_test_utils::pubkey(42),
7685 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7686 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7689 let blinded_payinfo = BlindedPayInfo {
7690 fee_base_msat: 5052_9027,
7691 fee_proportional_millionths: 0,
7692 htlc_minimum_msat: 21_7020_5185_1423_0019,
7693 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7694 cltv_expiry_delta: 0,
7695 features: BlindedHopFeatures::empty(),
7697 let mut blinded_hints = vec![
7698 (blinded_payinfo.clone(), blinded_path.clone()),
7699 (blinded_payinfo.clone(), blinded_path.clone()),
7701 blinded_hints[1].1.introduction_node_id = nodes[6];
7703 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7704 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7705 .with_bolt12_features(bolt12_features.clone()).unwrap();
7707 let netgraph = network_graph.read_only();
7708 let route_params = RouteParameters::from_payment_params_and_value(
7709 payment_params, amt_msat);
7710 if let Err(LightningError { err, .. }) = get_route(
7711 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7713 assert_eq!(err, "Failed to find a path to the given destination");
7718 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7719 // This previously led to a debug panic in the router because we'd find an invalid Path with
7720 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7721 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7722 // the payment, when it was intended to only include the final value of the payment.
7723 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7724 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7725 let scorer = ln_test_utils::TestScorer::new();
7726 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7727 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7728 let config = UserConfig::default();
7730 // Values are taken from the fuzz input that uncovered this panic.
7731 let amt_msat = 21_7020_5185_1423_0019;
7733 let blinded_path = BlindedPath {
7734 introduction_node_id: our_id,
7735 blinding_point: ln_test_utils::pubkey(42),
7737 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7738 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7741 let blinded_payinfo = BlindedPayInfo {
7742 fee_base_msat: 10_4425_1395,
7743 fee_proportional_millionths: 0,
7744 htlc_minimum_msat: 21_7301_9934_9094_0931,
7745 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7746 cltv_expiry_delta: 0,
7747 features: BlindedHopFeatures::empty(),
7749 let mut blinded_hints = vec![
7750 (blinded_payinfo.clone(), blinded_path.clone()),
7751 (blinded_payinfo.clone(), blinded_path.clone()),
7752 (blinded_payinfo.clone(), blinded_path.clone()),
7754 blinded_hints[1].0.fee_base_msat = 5052_9027;
7755 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7756 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7758 blinded_hints[2].1.introduction_node_id = nodes[6];
7760 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7761 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7762 .with_bolt12_features(bolt12_features.clone()).unwrap();
7764 let netgraph = network_graph.read_only();
7765 let route_params = RouteParameters::from_payment_params_and_value(
7766 payment_params, amt_msat);
7767 if let Err(LightningError { err, .. }) = get_route(
7768 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7770 assert_eq!(err, "Failed to find a path to the given destination");
7775 fn min_htlc_overpay_violates_max_htlc() {
7776 do_min_htlc_overpay_violates_max_htlc(true);
7777 do_min_htlc_overpay_violates_max_htlc(false);
7779 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7780 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7781 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7782 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7783 // that the used liquidity for a hop was less than its available liquidity limit.
7784 let secp_ctx = Secp256k1::new();
7785 let logger = Arc::new(ln_test_utils::TestLogger::new());
7786 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7787 let scorer = ln_test_utils::TestScorer::new();
7788 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7789 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7790 let config = UserConfig::default();
7792 // Values are taken from the fuzz input that uncovered this panic.
7793 let amt_msat = 7_4009_8048;
7794 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7795 let first_hop_outbound_capacity = 2_7345_2000;
7796 let first_hops = vec![get_channel_details(
7797 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7798 first_hop_outbound_capacity
7801 let base_fee = 1_6778_3453;
7802 let htlc_min = 2_5165_8240;
7803 let payment_params = if blinded_payee {
7804 let blinded_path = BlindedPath {
7805 introduction_node_id: nodes[0],
7806 blinding_point: ln_test_utils::pubkey(42),
7808 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7809 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7812 let blinded_payinfo = BlindedPayInfo {
7813 fee_base_msat: base_fee,
7814 fee_proportional_millionths: 0,
7815 htlc_minimum_msat: htlc_min,
7816 htlc_maximum_msat: htlc_min * 1000,
7817 cltv_expiry_delta: 0,
7818 features: BlindedHopFeatures::empty(),
7820 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7821 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7822 .with_bolt12_features(bolt12_features.clone()).unwrap()
7824 let route_hint = RouteHint(vec![RouteHintHop {
7825 src_node_id: nodes[0],
7826 short_channel_id: 42,
7828 base_msat: base_fee,
7829 proportional_millionths: 0,
7831 cltv_expiry_delta: 10,
7832 htlc_minimum_msat: Some(htlc_min),
7833 htlc_maximum_msat: None,
7836 PaymentParameters::from_node_id(nodes[1], 42)
7837 .with_route_hints(vec![route_hint]).unwrap()
7838 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7841 let netgraph = network_graph.read_only();
7842 let route_params = RouteParameters::from_payment_params_and_value(
7843 payment_params, amt_msat);
7844 if let Err(LightningError { err, .. }) = get_route(
7845 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7846 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7848 assert_eq!(err, "Failed to find a path to the given destination");
7853 fn previously_used_liquidity_violates_max_htlc() {
7854 do_previously_used_liquidity_violates_max_htlc(true);
7855 do_previously_used_liquidity_violates_max_htlc(false);
7858 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7859 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7860 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7861 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7862 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7863 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7864 let secp_ctx = Secp256k1::new();
7865 let logger = Arc::new(ln_test_utils::TestLogger::new());
7866 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7867 let scorer = ln_test_utils::TestScorer::new();
7868 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7869 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7870 let config = UserConfig::default();
7872 // Values are taken from the fuzz input that uncovered this panic.
7873 let amt_msat = 52_4288;
7874 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7875 let first_hops = vec![get_channel_details(
7876 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7877 ), get_channel_details(
7878 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7881 let base_fees = [0, 425_9840, 0, 0];
7882 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7883 let payment_params = if blinded_payee {
7884 let blinded_path = BlindedPath {
7885 introduction_node_id: nodes[0],
7886 blinding_point: ln_test_utils::pubkey(42),
7888 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7889 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7892 let mut blinded_hints = Vec::new();
7893 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7894 blinded_hints.push((BlindedPayInfo {
7895 fee_base_msat: *base_fee,
7896 fee_proportional_millionths: 0,
7897 htlc_minimum_msat: *htlc_min,
7898 htlc_maximum_msat: htlc_min * 100,
7899 cltv_expiry_delta: 10,
7900 features: BlindedHopFeatures::empty(),
7901 }, blinded_path.clone()));
7903 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7904 PaymentParameters::blinded(blinded_hints.clone())
7905 .with_bolt12_features(bolt12_features.clone()).unwrap()
7907 let mut route_hints = Vec::new();
7908 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7909 route_hints.push(RouteHint(vec![RouteHintHop {
7910 src_node_id: nodes[0],
7911 short_channel_id: 42 + idx as u64,
7913 base_msat: *base_fee,
7914 proportional_millionths: 0,
7916 cltv_expiry_delta: 10,
7917 htlc_minimum_msat: Some(*htlc_min),
7918 htlc_maximum_msat: Some(htlc_min * 100),
7921 PaymentParameters::from_node_id(nodes[1], 42)
7922 .with_route_hints(route_hints).unwrap()
7923 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7926 let netgraph = network_graph.read_only();
7927 let route_params = RouteParameters::from_payment_params_and_value(
7928 payment_params, amt_msat);
7930 let route = get_route(
7931 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7932 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7934 assert_eq!(route.paths.len(), 1);
7935 assert_eq!(route.get_total_amount(), amt_msat);
7939 fn candidate_path_min() {
7940 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7941 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7942 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7943 // would add a connecting first_hop node that did not have enough contribution amount, leading
7944 // to a debug panic upon invalid path construction.
7945 let secp_ctx = Secp256k1::new();
7946 let logger = Arc::new(ln_test_utils::TestLogger::new());
7947 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7948 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7949 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7950 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7951 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7952 let config = UserConfig::default();
7954 // Values are taken from the fuzz input that uncovered this panic.
7955 let amt_msat = 7_4009_8048;
7956 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7957 let first_hops = vec![get_channel_details(
7958 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7961 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7962 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7963 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7964 short_channel_id: 6,
7967 cltv_expiry_delta: (6 << 4) | 0,
7968 htlc_minimum_msat: 0,
7969 htlc_maximum_msat: MAX_VALUE_MSAT,
7971 fee_proportional_millionths: 0,
7972 excess_data: Vec::new()
7974 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7976 let htlc_min = 2_5165_8240;
7977 let blinded_hints = vec![
7979 fee_base_msat: 1_6778_3453,
7980 fee_proportional_millionths: 0,
7981 htlc_minimum_msat: htlc_min,
7982 htlc_maximum_msat: htlc_min * 100,
7983 cltv_expiry_delta: 10,
7984 features: BlindedHopFeatures::empty(),
7986 introduction_node_id: nodes[0],
7987 blinding_point: ln_test_utils::pubkey(42),
7989 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7990 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7994 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7995 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7996 .with_bolt12_features(bolt12_features.clone()).unwrap();
7997 let route_params = RouteParameters::from_payment_params_and_value(
7998 payment_params, amt_msat);
7999 let netgraph = network_graph.read_only();
8001 if let Err(LightningError { err, .. }) = get_route(
8002 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8003 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8006 assert_eq!(err, "Failed to find a path to the given destination");
8011 fn path_contribution_includes_min_htlc_overpay() {
8012 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
8013 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
8014 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
8015 // selection, both tested here.
8016 let secp_ctx = Secp256k1::new();
8017 let logger = Arc::new(ln_test_utils::TestLogger::new());
8018 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8019 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
8020 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8021 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8022 let config = UserConfig::default();
8024 // Values are taken from the fuzz input that uncovered this panic.
8025 let amt_msat = 562_0000;
8026 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8027 let first_hops = vec![
8028 get_channel_details(
8029 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
8033 let htlc_mins = [49_0000, 1125_0000];
8034 let payment_params = {
8035 let blinded_path = BlindedPath {
8036 introduction_node_id: nodes[0],
8037 blinding_point: ln_test_utils::pubkey(42),
8039 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8040 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8043 let mut blinded_hints = Vec::new();
8044 for htlc_min in htlc_mins.iter() {
8045 blinded_hints.push((BlindedPayInfo {
8047 fee_proportional_millionths: 0,
8048 htlc_minimum_msat: *htlc_min,
8049 htlc_maximum_msat: *htlc_min * 100,
8050 cltv_expiry_delta: 10,
8051 features: BlindedHopFeatures::empty(),
8052 }, blinded_path.clone()));
8054 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8055 PaymentParameters::blinded(blinded_hints.clone())
8056 .with_bolt12_features(bolt12_features.clone()).unwrap()
8059 let netgraph = network_graph.read_only();
8060 let route_params = RouteParameters::from_payment_params_and_value(
8061 payment_params, amt_msat);
8062 let route = get_route(
8063 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8064 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8067 assert_eq!(route.paths.len(), 1);
8068 assert_eq!(route.get_total_amount(), amt_msat);
8072 fn first_hop_preferred_over_hint() {
8073 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
8074 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
8075 let secp_ctx = Secp256k1::new();
8076 let logger = Arc::new(ln_test_utils::TestLogger::new());
8077 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8078 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
8079 let scorer = ln_test_utils::TestScorer::new();
8080 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8081 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8082 let config = UserConfig::default();
8084 let amt_msat = 1_000_000;
8085 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
8087 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
8088 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
8089 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
8090 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8091 short_channel_id: 1,
8094 cltv_expiry_delta: 42,
8095 htlc_minimum_msat: 1_000,
8096 htlc_maximum_msat: 10_000_000,
8098 fee_proportional_millionths: 0,
8099 excess_data: Vec::new()
8101 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8102 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8103 short_channel_id: 1,
8106 cltv_expiry_delta: 42,
8107 htlc_minimum_msat: 1_000,
8108 htlc_maximum_msat: 10_000_000,
8110 fee_proportional_millionths: 0,
8111 excess_data: Vec::new()
8114 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
8115 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
8116 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8117 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8118 short_channel_id: 2,
8121 cltv_expiry_delta: 42,
8122 htlc_minimum_msat: 1_000,
8123 htlc_maximum_msat: 10_000_000,
8125 fee_proportional_millionths: 0,
8126 excess_data: Vec::new()
8128 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
8129 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8130 short_channel_id: 2,
8133 cltv_expiry_delta: 42,
8134 htlc_minimum_msat: 1_000,
8135 htlc_maximum_msat: 10_000_000,
8137 fee_proportional_millionths: 0,
8138 excess_data: Vec::new()
8141 let dest_node_id = nodes[2];
8143 let route_hint = RouteHint(vec![RouteHintHop {
8144 src_node_id: our_node_id,
8145 short_channel_id: 44,
8148 proportional_millionths: 0,
8150 cltv_expiry_delta: 10,
8151 htlc_minimum_msat: None,
8152 htlc_maximum_msat: Some(5_000_000),
8155 src_node_id: nodes[0],
8156 short_channel_id: 45,
8159 proportional_millionths: 0,
8161 cltv_expiry_delta: 10,
8162 htlc_minimum_msat: None,
8163 htlc_maximum_msat: None,
8166 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8167 .with_route_hints(vec![route_hint]).unwrap()
8168 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8169 let route_params = RouteParameters::from_payment_params_and_value(
8170 payment_params, amt_msat);
8172 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8174 let first_hop = get_channel_details(Some(1), nodes[0],
8175 channelmanager::provided_init_features(&config), 999_999);
8176 let first_hops = vec![first_hop];
8178 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8179 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8180 &Default::default(), &random_seed_bytes).unwrap();
8181 assert_eq!(route.paths.len(), 1);
8182 assert_eq!(route.get_total_amount(), amt_msat);
8183 assert_eq!(route.paths[0].hops.len(), 2);
8184 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8185 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8186 assert_eq!(route.get_total_fees(), 123);
8188 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8189 // for a first hop channel.
8190 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8191 first_hop.outbound_scid_alias = Some(44);
8192 let first_hops = vec![first_hop];
8194 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8195 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8196 &Default::default(), &random_seed_bytes);
8197 assert!(route_res.is_err());
8199 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8200 // use the cheaper second hop of the route hint.
8201 let mut first_hop = get_channel_details(Some(1), nodes[0],
8202 channelmanager::provided_init_features(&config), 10_000_000);
8203 first_hop.outbound_scid_alias = Some(44);
8204 let first_hops = vec![first_hop];
8206 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8207 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8208 &Default::default(), &random_seed_bytes).unwrap();
8209 assert_eq!(route.paths.len(), 1);
8210 assert_eq!(route.get_total_amount(), amt_msat);
8211 assert_eq!(route.paths[0].hops.len(), 2);
8212 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8213 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8214 assert_eq!(route.get_total_fees(), 123);
8218 fn allow_us_being_first_hint() {
8219 // Check that we consider a route hint even if we are the src of the first hop.
8220 let secp_ctx = Secp256k1::new();
8221 let logger = Arc::new(ln_test_utils::TestLogger::new());
8222 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8223 let scorer = ln_test_utils::TestScorer::new();
8224 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8225 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8226 let config = UserConfig::default();
8228 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8230 let amt_msat = 1_000_000;
8231 let dest_node_id = nodes[1];
8233 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8234 let first_hops = vec![first_hop];
8236 let route_hint = RouteHint(vec![RouteHintHop {
8237 src_node_id: our_node_id,
8238 short_channel_id: 44,
8241 proportional_millionths: 0,
8243 cltv_expiry_delta: 10,
8244 htlc_minimum_msat: None,
8245 htlc_maximum_msat: None,
8248 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8249 .with_route_hints(vec![route_hint]).unwrap()
8250 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8252 let route_params = RouteParameters::from_payment_params_and_value(
8253 payment_params, amt_msat);
8256 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8257 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8258 &Default::default(), &random_seed_bytes).unwrap();
8260 assert_eq!(route.paths.len(), 1);
8261 assert_eq!(route.get_total_amount(), amt_msat);
8262 assert_eq!(route.get_total_fees(), 0);
8263 assert_eq!(route.paths[0].hops.len(), 1);
8265 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8269 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
8270 pub(crate) mod bench_utils {
8273 use std::time::Duration;
8275 use bitcoin::hashes::Hash;
8276 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
8278 use crate::chain::transaction::OutPoint;
8279 use crate::routing::scoring::ScoreUpdate;
8280 use crate::sign::{EntropySource, KeysManager};
8281 use crate::ln::ChannelId;
8282 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
8283 use crate::ln::features::Bolt11InvoiceFeatures;
8284 use crate::routing::gossip::NetworkGraph;
8285 use crate::util::config::UserConfig;
8286 use crate::util::ser::ReadableArgs;
8287 use crate::util::test_utils::TestLogger;
8289 /// Tries to open a network graph file, or panics with a URL to fetch it.
8290 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
8291 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
8292 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
8293 .or_else(|_| { // Fall back to guessing based on the binary location
8294 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8295 let mut path = std::env::current_exe().unwrap();
8296 path.pop(); // lightning-...
8298 path.pop(); // debug
8299 path.pop(); // target
8300 path.push("lightning");
8301 path.push("net_graph-2023-01-18.bin");
8304 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8305 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8306 let mut path = std::env::current_exe().unwrap();
8307 path.pop(); // bench...
8309 path.pop(); // debug
8310 path.pop(); // target
8311 path.pop(); // bench
8312 path.push("lightning");
8313 path.push("net_graph-2023-01-18.bin");
8316 .map_err(|_| "Please fetch https://bitcoin.ninja/ldk-net_graph-v0.0.113-2023-01-18.bin and place it at lightning/net_graph-2023-01-18.bin");
8317 #[cfg(require_route_graph_test)]
8318 return Ok(res.unwrap());
8319 #[cfg(not(require_route_graph_test))]
8323 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
8324 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
8327 pub(crate) fn payer_pubkey() -> PublicKey {
8328 let secp_ctx = Secp256k1::new();
8329 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8333 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8335 channel_id: ChannelId::new_zero(),
8336 counterparty: ChannelCounterparty {
8337 features: channelmanager::provided_init_features(&UserConfig::default()),
8339 unspendable_punishment_reserve: 0,
8340 forwarding_info: None,
8341 outbound_htlc_minimum_msat: None,
8342 outbound_htlc_maximum_msat: None,
8344 funding_txo: Some(OutPoint {
8345 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8348 short_channel_id: Some(1),
8349 inbound_scid_alias: None,
8350 outbound_scid_alias: None,
8351 channel_value_satoshis: 10_000_000_000,
8353 balance_msat: 10_000_000_000,
8354 outbound_capacity_msat: 10_000_000_000,
8355 next_outbound_htlc_minimum_msat: 0,
8356 next_outbound_htlc_limit_msat: 10_000_000_000,
8357 inbound_capacity_msat: 0,
8358 unspendable_punishment_reserve: None,
8359 confirmations_required: None,
8360 confirmations: None,
8361 force_close_spend_delay: None,
8363 is_channel_ready: true,
8366 inbound_htlc_minimum_msat: None,
8367 inbound_htlc_maximum_msat: None,
8369 feerate_sat_per_1000_weight: None,
8370 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
8374 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8375 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8376 starting_amount: u64, route_count: usize,
8377 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8378 let payer = payer_pubkey();
8379 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8380 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8382 let nodes = graph.read_only().nodes().clone();
8383 let mut route_endpoints = Vec::new();
8384 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
8385 // with some routes we picked being un-routable.
8386 for _ in 0..route_count * 3 / 2 {
8388 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8389 let src = PublicKey::from_slice(nodes.unordered_keys()
8390 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8391 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8392 let dst = PublicKey::from_slice(nodes.unordered_keys()
8393 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8394 let params = PaymentParameters::from_node_id(dst, 42)
8395 .with_bolt11_features(features.clone()).unwrap();
8396 let first_hop = first_hop(src);
8397 let amt_msat = starting_amount + seed % 1_000_000;
8398 let route_params = RouteParameters::from_payment_params_and_value(
8399 params.clone(), amt_msat);
8401 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8402 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8404 // ...and seed the scorer with success and failure data...
8405 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8406 let mut score_amt = seed % 1_000_000_000;
8408 // Generate fail/success paths for a wider range of potential amounts with
8409 // MPP enabled to give us a chance to apply penalties for more potential
8411 let mpp_features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
8412 let params = PaymentParameters::from_node_id(dst, 42)
8413 .with_bolt11_features(mpp_features).unwrap();
8414 let route_params = RouteParameters::from_payment_params_and_value(
8415 params.clone(), score_amt);
8416 let route_res = get_route(&payer, &route_params, &graph.read_only(),
8417 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
8418 &random_seed_bytes);
8419 if let Ok(route) = route_res {
8420 for path in route.paths {
8421 if seed & 0x80 == 0 {
8422 scorer.payment_path_successful(&path, Duration::ZERO);
8424 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
8425 scorer.payment_path_failed(&path, short_channel_id, Duration::ZERO);
8427 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8431 // If we couldn't find a path with a higer amount, reduce and try again.
8435 route_endpoints.push((first_hop, params, amt_msat));
8441 // Because we've changed channel scores, it's possible we'll take different routes to the
8442 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
8443 // requires a too-high CLTV delta.
8444 route_endpoints.retain(|(first_hop, params, amt_msat)| {
8445 let route_params = RouteParameters::from_payment_params_and_value(
8446 params.clone(), *amt_msat);
8447 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8448 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
8450 route_endpoints.truncate(route_count);
8451 assert_eq!(route_endpoints.len(), route_count);
8459 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8460 use crate::sign::{EntropySource, KeysManager};
8461 use crate::ln::channelmanager;
8462 use crate::ln::features::Bolt11InvoiceFeatures;
8463 use crate::routing::gossip::NetworkGraph;
8464 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
8465 use crate::util::config::UserConfig;
8466 use crate::util::logger::{Logger, Record};
8467 use crate::util::test_utils::TestLogger;
8469 use criterion::Criterion;
8471 struct DummyLogger {}
8472 impl Logger for DummyLogger {
8473 fn log(&self, _record: Record) {}
8476 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8477 let logger = TestLogger::new();
8478 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8479 let scorer = FixedPenaltyScorer::with_penalty(0);
8480 generate_routes(bench, &network_graph, scorer, &Default::default(),
8481 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8484 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8485 let logger = TestLogger::new();
8486 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8487 let scorer = FixedPenaltyScorer::with_penalty(0);
8488 generate_routes(bench, &network_graph, scorer, &Default::default(),
8489 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8490 "generate_mpp_routes_with_zero_penalty_scorer");
8493 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8494 let logger = TestLogger::new();
8495 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8496 let params = ProbabilisticScoringFeeParameters::default();
8497 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8498 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8499 "generate_routes_with_probabilistic_scorer");
8502 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8503 let logger = TestLogger::new();
8504 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8505 let params = ProbabilisticScoringFeeParameters::default();
8506 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8507 generate_routes(bench, &network_graph, scorer, ¶ms,
8508 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8509 "generate_mpp_routes_with_probabilistic_scorer");
8512 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8513 let logger = TestLogger::new();
8514 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8515 let params = ProbabilisticScoringFeeParameters::default();
8516 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8517 generate_routes(bench, &network_graph, scorer, ¶ms,
8518 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8519 "generate_large_mpp_routes_with_probabilistic_scorer");
8522 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8523 let logger = TestLogger::new();
8524 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8525 let mut params = ProbabilisticScoringFeeParameters::default();
8526 params.linear_success_probability = false;
8527 let scorer = ProbabilisticScorer::new(
8528 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8529 generate_routes(bench, &network_graph, scorer, ¶ms,
8530 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8531 "generate_routes_with_nonlinear_probabilistic_scorer");
8534 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8535 let logger = TestLogger::new();
8536 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8537 let mut params = ProbabilisticScoringFeeParameters::default();
8538 params.linear_success_probability = false;
8539 let scorer = ProbabilisticScorer::new(
8540 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8541 generate_routes(bench, &network_graph, scorer, ¶ms,
8542 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8543 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8546 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8547 let logger = TestLogger::new();
8548 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8549 let mut params = ProbabilisticScoringFeeParameters::default();
8550 params.linear_success_probability = false;
8551 let scorer = ProbabilisticScorer::new(
8552 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8553 generate_routes(bench, &network_graph, scorer, ¶ms,
8554 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8555 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8558 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8559 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8560 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8561 bench_name: &'static str,
8563 let payer = bench_utils::payer_pubkey();
8564 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8565 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8567 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8568 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8570 // ...then benchmark finding paths between the nodes we learned.
8572 bench.bench_function(bench_name, |b| b.iter(|| {
8573 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8574 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8575 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8576 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());