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 if network_graph.nodes().contains_key(&NodeId::from_pubkey(&recipient)) {
157 BlindedPath::one_hop_for_payment(recipient, tlvs, entropy_source, secp_ctx)
158 .map(|path| vec![path])
167 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
169 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
172 &self, sender: PublicKey, peers: Vec<PublicKey>, destination: Destination
173 ) -> Result<OnionMessagePath, ()> {
174 self.message_router.find_path(sender, peers, destination)
177 fn create_blinded_paths<
178 ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification
180 &self, recipient: PublicKey, peers: Vec<PublicKey>, entropy_source: &ES,
181 secp_ctx: &Secp256k1<T>
182 ) -> Result<Vec<BlindedPath>, ()> {
183 self.message_router.create_blinded_paths(recipient, peers, entropy_source, secp_ctx)
187 /// A trait defining behavior for routing a payment.
188 pub trait Router: MessageRouter {
189 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
191 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
192 /// and [`RouteParameters::final_value_msat`], respectively.
194 &self, payer: &PublicKey, route_params: &RouteParameters,
195 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
196 ) -> Result<Route, LightningError>;
198 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
200 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
201 /// and [`RouteParameters::final_value_msat`], respectively.
203 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
205 fn find_route_with_id(
206 &self, payer: &PublicKey, route_params: &RouteParameters,
207 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
208 _payment_hash: PaymentHash, _payment_id: PaymentId
209 ) -> Result<Route, LightningError> {
210 self.find_route(payer, route_params, first_hops, inflight_htlcs)
213 /// Creates [`BlindedPath`]s for payment to the `recipient` node. The channels in `first_hops`
214 /// are assumed to be with the `recipient`'s peers. The payment secret and any constraints are
216 fn create_blinded_payment_paths<
217 ES: EntropySource + ?Sized, T: secp256k1::Signing + secp256k1::Verification
219 &self, recipient: PublicKey, first_hops: Vec<ChannelDetails>, tlvs: ReceiveTlvs,
220 amount_msats: u64, entropy_source: &ES, secp_ctx: &Secp256k1<T>
221 ) -> Result<Vec<(BlindedPayInfo, BlindedPath)>, ()>;
224 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
226 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
229 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
230 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Deref> where S::Target: ScoreLookUp {
232 // Maps a channel's short channel id and its direction to the liquidity used up.
233 inflight_htlcs: &'a InFlightHtlcs,
235 impl<'a, S: Deref> ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
236 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
237 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
238 ScorerAccountingForInFlightHtlcs {
245 impl<'a, S: Deref> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
246 type ScoreParams = <S::Target as ScoreLookUp>::ScoreParams;
247 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
248 let target = match candidate.target() {
249 Some(target) => target,
250 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
252 let short_channel_id = match candidate.short_channel_id() {
253 Some(short_channel_id) => short_channel_id,
254 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
256 let source = candidate.source();
257 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
258 &source, &target, short_channel_id
260 let usage = ChannelUsage {
261 inflight_htlc_msat: usage.inflight_htlc_msat.saturating_add(used_liquidity),
265 self.scorer.channel_penalty_msat(candidate, usage, score_params)
267 self.scorer.channel_penalty_msat(candidate, usage, score_params)
272 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
273 /// in-use channel liquidity.
275 pub struct InFlightHtlcs(
276 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
277 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
278 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
280 HashMap<(u64, bool), u64>
284 /// Constructs an empty `InFlightHtlcs`.
285 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
287 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
288 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
289 if path.hops.is_empty() { return };
291 let mut cumulative_msat = 0;
292 if let Some(tail) = &path.blinded_tail {
293 cumulative_msat += tail.final_value_msat;
296 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
297 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
298 // the router excludes the payer node. In the following lines, the payer's information is
299 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
300 // in our sliding window of two.
301 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
302 .map(|hop| hop.pubkey)
303 .chain(core::iter::once(payer_node_id));
305 // Taking the reversed vector from above, we zip it with just the reversed hops list to
306 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
307 // the total amount sent.
308 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
309 cumulative_msat += next_hop.fee_msat;
311 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
312 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
313 .or_insert(cumulative_msat);
317 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
319 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
321 .entry((channel_scid, source < target))
322 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
323 .or_insert(used_msat);
326 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
328 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
329 self.0.get(&(channel_scid, source < target)).map(|v| *v)
333 impl Writeable for InFlightHtlcs {
334 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
337 impl Readable for InFlightHtlcs {
338 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
339 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
340 Ok(Self(infight_map))
344 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
345 /// that leads to it.
346 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
347 pub struct RouteHop {
348 /// The node_id of the node at this hop.
349 pub pubkey: PublicKey,
350 /// The node_announcement features of the node at this hop. For the last hop, these may be
351 /// amended to match the features present in the invoice this node generated.
352 pub node_features: NodeFeatures,
353 /// The channel that should be used from the previous hop to reach this node.
354 pub short_channel_id: u64,
355 /// The channel_announcement features of the channel that should be used from the previous hop
356 /// to reach this node.
357 pub channel_features: ChannelFeatures,
358 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
359 /// If this is the last hop in [`Path::hops`]:
360 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
361 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
363 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
365 /// The CLTV delta added for this hop.
366 /// If this is the last hop in [`Path::hops`]:
367 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
368 /// * otherwise, this is the CLTV delta expected at the destination
370 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
371 pub cltv_expiry_delta: u32,
372 /// Indicates whether this hop is possibly announced in the public network graph.
374 /// Will be `true` if there is a possibility that the channel is publicly known, i.e., if we
375 /// either know for sure it's announced in the public graph, or if any public channels exist
376 /// for which the given `short_channel_id` could be an alias for. Will be `false` if we believe
377 /// the channel to be unannounced.
379 /// Will be `true` for objects serialized with LDK version 0.0.116 and before.
380 pub maybe_announced_channel: bool,
383 impl_writeable_tlv_based!(RouteHop, {
384 (0, pubkey, required),
385 (1, maybe_announced_channel, (default_value, true)),
386 (2, node_features, required),
387 (4, short_channel_id, required),
388 (6, channel_features, required),
389 (8, fee_msat, required),
390 (10, cltv_expiry_delta, required),
393 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
394 /// their [`Bolt12Invoice`].
396 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
397 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
398 pub struct BlindedTail {
399 /// The hops of the [`BlindedPath`] provided by the recipient.
401 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
402 pub hops: Vec<BlindedHop>,
403 /// The blinding point of the [`BlindedPath`] provided by the recipient.
405 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
406 pub blinding_point: PublicKey,
407 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
408 /// inferring the destination. May be 0.
409 pub excess_final_cltv_expiry_delta: u32,
410 /// The total amount paid on this [`Path`], excluding the fees.
411 pub final_value_msat: u64,
414 impl_writeable_tlv_based!(BlindedTail, {
415 (0, hops, required_vec),
416 (2, blinding_point, required),
417 (4, excess_final_cltv_expiry_delta, required),
418 (6, final_value_msat, required),
421 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
422 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
423 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
425 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
426 pub hops: Vec<RouteHop>,
427 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
428 pub blinded_tail: Option<BlindedTail>,
432 /// Gets the fees for a given path, excluding any excess paid to the recipient.
433 pub fn fee_msat(&self) -> u64 {
434 match &self.blinded_tail {
435 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
437 // Do not count last hop of each path since that's the full value of the payment
438 self.hops.split_last().map_or(0,
439 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
444 /// Gets the total amount paid on this [`Path`], excluding the fees.
445 pub fn final_value_msat(&self) -> u64 {
446 match &self.blinded_tail {
447 Some(blinded_tail) => blinded_tail.final_value_msat,
448 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
452 /// Gets the final hop's CLTV expiry delta.
453 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
454 match &self.blinded_tail {
456 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
461 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
462 /// it can take multiple paths. Each path is composed of one or more hops through the network.
463 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
465 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
466 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
468 pub paths: Vec<Path>,
469 /// The `route_params` parameter passed to [`find_route`].
471 /// This is used by `ChannelManager` to track information which may be required for retries.
473 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
474 pub route_params: Option<RouteParameters>,
478 /// Returns the total amount of fees paid on this [`Route`].
480 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
481 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
482 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
484 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
485 pub fn get_total_fees(&self) -> u64 {
486 let overpaid_value_msat = self.route_params.as_ref()
487 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
488 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
491 /// Returns the total amount paid on this [`Route`], excluding the fees.
493 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
494 /// we had to reach the [`htlc_minimum_msat`] limits.
496 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
497 pub fn get_total_amount(&self) -> u64 {
498 self.paths.iter().map(|path| path.final_value_msat()).sum()
502 impl fmt::Display for Route {
503 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
504 log_route!(self).fmt(f)
508 const SERIALIZATION_VERSION: u8 = 1;
509 const MIN_SERIALIZATION_VERSION: u8 = 1;
511 impl Writeable for Route {
512 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
513 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
514 (self.paths.len() as u64).write(writer)?;
515 let mut blinded_tails = Vec::new();
516 for path in self.paths.iter() {
517 (path.hops.len() as u8).write(writer)?;
518 for (idx, hop) in path.hops.iter().enumerate() {
520 if let Some(blinded_tail) = &path.blinded_tail {
521 if blinded_tails.is_empty() {
522 blinded_tails = Vec::with_capacity(path.hops.len());
524 blinded_tails.push(None);
527 blinded_tails.push(Some(blinded_tail));
528 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
531 write_tlv_fields!(writer, {
532 // For compatibility with LDK versions prior to 0.0.117, we take the individual
533 // RouteParameters' fields and reconstruct them on read.
534 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
535 (2, blinded_tails, optional_vec),
536 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
537 (5, self.route_params.as_ref().map(|p| p.max_total_routing_fee_msat), option),
543 impl Readable for Route {
544 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
545 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
546 let path_count: u64 = Readable::read(reader)?;
547 if path_count == 0 { return Err(DecodeError::InvalidValue); }
548 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
549 let mut min_final_cltv_expiry_delta = u32::max_value();
550 for _ in 0..path_count {
551 let hop_count: u8 = Readable::read(reader)?;
552 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
553 for _ in 0..hop_count {
554 hops.push(Readable::read(reader)?);
556 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
557 min_final_cltv_expiry_delta =
558 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
559 paths.push(Path { hops, blinded_tail: None });
561 _init_and_read_len_prefixed_tlv_fields!(reader, {
562 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
563 (2, blinded_tails, optional_vec),
564 (3, final_value_msat, option),
565 (5, max_total_routing_fee_msat, option)
567 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
568 if blinded_tails.len() != 0 {
569 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
570 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
571 path.blinded_tail = blinded_tail_opt;
575 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
576 let route_params = match (payment_params, final_value_msat) {
577 (Some(payment_params), Some(final_value_msat)) => {
578 Some(RouteParameters { payment_params, final_value_msat, max_total_routing_fee_msat })
583 Ok(Route { paths, route_params })
587 /// Parameters needed to find a [`Route`].
589 /// Passed to [`find_route`] and [`build_route_from_hops`].
590 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
591 pub struct RouteParameters {
592 /// The parameters of the failed payment path.
593 pub payment_params: PaymentParameters,
595 /// The amount in msats sent on the failed payment path.
596 pub final_value_msat: u64,
598 /// The maximum total fees, in millisatoshi, that may accrue during route finding.
600 /// This limit also applies to the total fees that may arise while retrying failed payment
603 /// Note that values below a few sats may result in some paths being spuriously ignored.
604 pub max_total_routing_fee_msat: Option<u64>,
607 impl RouteParameters {
608 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
610 /// [`Self::max_total_routing_fee_msat`] defaults to 1% of the payment amount + 50 sats
611 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
612 Self { payment_params, final_value_msat, max_total_routing_fee_msat: Some(final_value_msat / 100 + 50_000) }
616 impl Writeable for RouteParameters {
617 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
618 write_tlv_fields!(writer, {
619 (0, self.payment_params, required),
620 (1, self.max_total_routing_fee_msat, option),
621 (2, self.final_value_msat, required),
622 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
623 // `RouteParameters` directly. For compatibility, we write it here.
624 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
630 impl Readable for RouteParameters {
631 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
632 _init_and_read_len_prefixed_tlv_fields!(reader, {
633 (0, payment_params, (required: ReadableArgs, 0)),
634 (1, max_total_routing_fee_msat, option),
635 (2, final_value_msat, required),
636 (4, final_cltv_delta, option),
638 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
639 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
640 if final_cltv_expiry_delta == &0 {
641 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
646 final_value_msat: final_value_msat.0.unwrap(),
647 max_total_routing_fee_msat,
652 /// Maximum total CTLV difference we allow for a full payment path.
653 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
655 /// Maximum number of paths we allow an (MPP) payment to have.
656 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
657 // limits, but for now more than 10 paths likely carries too much one-path failure.
658 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
660 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
662 // The median hop CLTV expiry delta currently seen in the network.
663 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
665 // During routing, we only consider paths shorter than our maximum length estimate.
666 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
667 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
668 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
670 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
671 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
672 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
673 // (payment_secret and total_msat) = 93 bytes for the final hop.
674 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
675 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
676 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
678 /// Information used to route a payment.
679 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
680 pub struct PaymentParameters {
681 /// Information about the payee, such as their features and route hints for their channels.
684 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
685 pub expiry_time: Option<u64>,
687 /// The maximum total CLTV delta we accept for the route.
688 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
689 pub max_total_cltv_expiry_delta: u32,
691 /// The maximum number of paths that may be used by (MPP) payments.
692 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
693 pub max_path_count: u8,
695 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
696 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
697 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
698 /// increasing failure probability for those paths.
700 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
701 /// restriction have been found. While paths which meet this criteria will be searched for, it
702 /// is ultimately up to the scorer to select them over other paths.
704 /// A value of 0 will allow payments up to and including a channel's total announced usable
705 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
708 pub max_channel_saturation_power_of_half: u8,
710 /// A list of SCIDs which this payment was previously attempted over and which caused the
711 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
713 pub previously_failed_channels: Vec<u64>,
716 impl Writeable for PaymentParameters {
717 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
718 let mut clear_hints = &vec![];
719 let mut blinded_hints = &vec![];
721 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
722 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
724 write_tlv_fields!(writer, {
725 (0, self.payee.node_id(), option),
726 (1, self.max_total_cltv_expiry_delta, required),
727 (2, self.payee.features(), option),
728 (3, self.max_path_count, required),
729 (4, *clear_hints, required_vec),
730 (5, self.max_channel_saturation_power_of_half, required),
731 (6, self.expiry_time, option),
732 (7, self.previously_failed_channels, required_vec),
733 (8, *blinded_hints, optional_vec),
734 (9, self.payee.final_cltv_expiry_delta(), option),
740 impl ReadableArgs<u32> for PaymentParameters {
741 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
742 _init_and_read_len_prefixed_tlv_fields!(reader, {
743 (0, payee_pubkey, option),
744 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
745 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
746 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
747 (4, clear_route_hints, required_vec),
748 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
749 (6, expiry_time, option),
750 (7, previously_failed_channels, optional_vec),
751 (8, blinded_route_hints, optional_vec),
752 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
754 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
755 let payee = if blinded_route_hints.len() != 0 {
756 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
758 route_hints: blinded_route_hints,
759 features: features.and_then(|f: Features| f.bolt12()),
763 route_hints: clear_route_hints,
764 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
765 features: features.and_then(|f| f.bolt11()),
766 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
770 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
771 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
773 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
775 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
781 impl PaymentParameters {
782 /// Creates a payee with the node id of the given `pubkey`.
784 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
786 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
788 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
790 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
791 max_path_count: DEFAULT_MAX_PATH_COUNT,
792 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
793 previously_failed_channels: Vec::new(),
797 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
799 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
802 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
803 /// whether your router will be allowed to find a multi-part route for this payment. If you
804 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
805 /// [`RecipientOnionFields::secret_only`].
807 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
808 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
809 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
810 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
811 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
814 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
815 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
816 /// [`PaymentParameters::expiry_time`].
817 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
818 Self::blinded(invoice.payment_paths().to_vec())
819 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
820 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
823 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
824 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
826 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
828 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
829 max_path_count: DEFAULT_MAX_PATH_COUNT,
830 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
831 previously_failed_channels: Vec::new(),
835 /// Includes the payee's features. Errors if the parameters were not initialized with
836 /// [`PaymentParameters::from_bolt12_invoice`].
838 /// This is not exported to bindings users since bindings don't support move semantics
839 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
841 Payee::Clear { .. } => Err(()),
842 Payee::Blinded { route_hints, .. } =>
843 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
847 /// Includes the payee's features. Errors if the parameters were initialized with
848 /// [`PaymentParameters::from_bolt12_invoice`].
850 /// This is not exported to bindings users since bindings don't support move semantics
851 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
853 Payee::Blinded { .. } => Err(()),
854 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
856 payee: Payee::Clear {
857 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
863 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
864 /// [`PaymentParameters::from_bolt12_invoice`].
866 /// This is not exported to bindings users since bindings don't support move semantics
867 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
869 Payee::Blinded { .. } => Err(()),
870 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
872 payee: Payee::Clear {
873 route_hints, node_id, features, final_cltv_expiry_delta,
879 /// Includes a payment expiration in seconds relative to the UNIX epoch.
881 /// This is not exported to bindings users since bindings don't support move semantics
882 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
883 Self { expiry_time: Some(expiry_time), ..self }
886 /// Includes a limit for the total CLTV expiry delta which is considered during routing
888 /// This is not exported to bindings users since bindings don't support move semantics
889 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
890 Self { max_total_cltv_expiry_delta, ..self }
893 /// Includes a limit for the maximum number of payment paths that may be used.
895 /// This is not exported to bindings users since bindings don't support move semantics
896 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
897 Self { max_path_count, ..self }
900 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
901 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
903 /// This is not exported to bindings users since bindings don't support move semantics
904 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
905 Self { max_channel_saturation_power_of_half, ..self }
909 /// The recipient of a payment, differing based on whether they've hidden their identity with route
911 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
913 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
914 /// will be included in the final [`Route`].
916 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
918 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
919 /// Features supported by the payee.
921 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
923 features: Option<Bolt12InvoiceFeatures>,
925 /// The recipient included these route hints in their BOLT11 invoice.
927 /// The node id of the payee.
929 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
930 route_hints: Vec<RouteHint>,
931 /// Features supported by the payee.
933 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
934 /// does not contain any features.
936 /// [`for_keysend`]: PaymentParameters::for_keysend
937 features: Option<Bolt11InvoiceFeatures>,
938 /// The minimum CLTV delta at the end of the route. This value must not be zero.
939 final_cltv_expiry_delta: u32,
944 fn node_id(&self) -> Option<PublicKey> {
946 Self::Clear { node_id, .. } => Some(*node_id),
950 fn node_features(&self) -> Option<NodeFeatures> {
952 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
953 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
956 fn supports_basic_mpp(&self) -> bool {
958 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
959 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
962 fn features(&self) -> Option<FeaturesRef> {
964 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
965 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
968 fn final_cltv_expiry_delta(&self) -> Option<u32> {
970 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
974 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
976 Self::Blinded { route_hints, .. } => &route_hints[..],
977 Self::Clear { .. } => &[]
981 fn unblinded_route_hints(&self) -> &[RouteHint] {
983 Self::Blinded { .. } => &[],
984 Self::Clear { route_hints, .. } => &route_hints[..]
989 enum FeaturesRef<'a> {
990 Bolt11(&'a Bolt11InvoiceFeatures),
991 Bolt12(&'a Bolt12InvoiceFeatures),
994 Bolt11(Bolt11InvoiceFeatures),
995 Bolt12(Bolt12InvoiceFeatures),
999 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
1001 Self::Bolt12(f) => Some(f),
1005 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
1007 Self::Bolt11(f) => Some(f),
1013 impl<'a> Writeable for FeaturesRef<'a> {
1014 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
1016 Self::Bolt11(f) => Ok(f.write(w)?),
1017 Self::Bolt12(f) => Ok(f.write(w)?),
1022 impl ReadableArgs<bool> for Features {
1023 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
1024 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
1025 Ok(Self::Bolt12(Readable::read(reader)?))
1029 /// A list of hops along a payment path terminating with a channel to the recipient.
1030 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1031 pub struct RouteHint(pub Vec<RouteHintHop>);
1033 impl Writeable for RouteHint {
1034 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
1035 (self.0.len() as u64).write(writer)?;
1036 for hop in self.0.iter() {
1043 impl Readable for RouteHint {
1044 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
1045 let hop_count: u64 = Readable::read(reader)?;
1046 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
1047 for _ in 0..hop_count {
1048 hops.push(Readable::read(reader)?);
1054 /// A channel descriptor for a hop along a payment path.
1056 /// While this generally comes from BOLT 11's `r` field, this struct includes more fields than are
1057 /// available in BOLT 11. Thus, encoding and decoding this via `lightning-invoice` is lossy, as
1058 /// fields not supported in BOLT 11 will be stripped.
1059 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
1060 pub struct RouteHintHop {
1061 /// The node_id of the non-target end of the route
1062 pub src_node_id: PublicKey,
1063 /// The short_channel_id of this channel
1064 pub short_channel_id: u64,
1065 /// The fees which must be paid to use this channel
1066 pub fees: RoutingFees,
1067 /// The difference in CLTV values between this node and the next node.
1068 pub cltv_expiry_delta: u16,
1069 /// The minimum value, in msat, which must be relayed to the next hop.
1070 pub htlc_minimum_msat: Option<u64>,
1071 /// The maximum value in msat available for routing with a single HTLC.
1072 pub htlc_maximum_msat: Option<u64>,
1075 impl_writeable_tlv_based!(RouteHintHop, {
1076 (0, src_node_id, required),
1077 (1, htlc_minimum_msat, option),
1078 (2, short_channel_id, required),
1079 (3, htlc_maximum_msat, option),
1080 (4, fees, required),
1081 (6, cltv_expiry_delta, required),
1084 #[derive(Eq, PartialEq)]
1085 #[repr(align(64))] // Force the size to 64 bytes
1086 struct RouteGraphNode {
1089 // The maximum value a yet-to-be-constructed payment path might flow through this node.
1090 // This value is upper-bounded by us by:
1091 // - how much is needed for a path being constructed
1092 // - how much value can channels following this node (up to the destination) can contribute,
1093 // considering their capacity and fees
1094 value_contribution_msat: u64,
1095 total_cltv_delta: u32,
1096 /// The number of hops walked up to this node.
1097 path_length_to_node: u8,
1100 impl cmp::Ord for RouteGraphNode {
1101 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
1102 other.score.cmp(&self.score).then_with(|| other.node_id.cmp(&self.node_id))
1106 impl cmp::PartialOrd for RouteGraphNode {
1107 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
1108 Some(self.cmp(other))
1112 // While RouteGraphNode can be laid out with fewer bytes, performance appears to be improved
1113 // substantially when it is laid out at exactly 64 bytes.
1115 // Thus, we use `#[repr(C)]` on the struct to force a suboptimal layout and check that it stays 64
1117 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1118 const _GRAPH_NODE_SMALL: usize = 64 - core::mem::size_of::<RouteGraphNode>();
1119 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1120 const _GRAPH_NODE_FIXED_SIZE: usize = core::mem::size_of::<RouteGraphNode>() - 64;
1122 /// A wrapper around the various hop representations.
1124 /// Can be used to examine the properties of a hop,
1125 /// potentially to decide whether to include it in a route.
1126 #[derive(Clone, Debug)]
1127 pub enum CandidateRouteHop<'a> {
1128 /// A hop from the payer, where the outbound liquidity is known.
1130 /// Channel details of the first hop
1132 /// [`ChannelDetails::get_outbound_payment_scid`] MUST be `Some` (indicating the channel
1133 /// has been funded and is able to pay), and accessor methods may panic otherwise.
1135 /// [`find_route`] validates this prior to constructing a [`CandidateRouteHop`].
1136 details: &'a ChannelDetails,
1137 /// The node id of the payer, which is also the source side of this candidate route hop.
1138 payer_node_id: &'a NodeId,
1140 /// A hop found in the [`ReadOnlyNetworkGraph`].
1142 /// Information about the channel, including potentially its capacity and
1143 /// direction-specific information.
1144 info: DirectedChannelInfo<'a>,
1145 /// The short channel ID of the channel, i.e. the identifier by which we refer to this
1147 short_channel_id: u64,
1149 /// A private hop communicated by the payee, generally via a BOLT 11 invoice.
1151 /// Because BOLT 11 route hints can take multiple hops to get to the destination, this may not
1152 /// terminate at the payee.
1154 /// Information about the private hop communicated via BOLT 11.
1155 hint: &'a RouteHintHop,
1156 /// Node id of the next hop in BOLT 11 route hint.
1157 target_node_id: &'a NodeId
1159 /// A blinded path which starts with an introduction point and ultimately terminates with the
1162 /// Because we don't know the payee's identity, [`CandidateRouteHop::target`] will return
1163 /// `None` in this state.
1165 /// Because blinded paths are "all or nothing", and we cannot use just one part of a blinded
1166 /// path, the full path is treated as a single [`CandidateRouteHop`].
1168 /// Information about the blinded path including the fee, HTLC amount limits, and
1169 /// cryptographic material required to build an HTLC through the given path.
1170 hint: &'a (BlindedPayInfo, BlindedPath),
1171 /// Index of the hint in the original list of blinded hints.
1173 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1174 /// a short channel ID for this hop.
1177 /// Similar to [`Self::Blinded`], but the path here only has one hop.
1179 /// While we treat this similarly to [`CandidateRouteHop::Blinded`] in many respects (e.g.
1180 /// returning `None` from [`CandidateRouteHop::target`]), in this case we do actually know the
1181 /// payee's identity - it's the introduction point!
1183 /// [`BlindedPayInfo`] provided for 1-hop blinded paths is ignored because it is meant to apply
1184 /// to the hops *between* the introduction node and the destination.
1186 /// This primarily exists to track that we need to included a blinded path at the end of our
1187 /// [`Route`], even though it doesn't actually add an additional hop in the payment.
1189 /// Information about the blinded path including the fee, HTLC amount limits, and
1190 /// cryptographic material required to build an HTLC terminating with the given path.
1192 /// Note that the [`BlindedPayInfo`] is ignored here.
1193 hint: &'a (BlindedPayInfo, BlindedPath),
1194 /// Index of the hint in the original list of blinded hints.
1196 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1197 /// a short channel ID for this hop.
1202 impl<'a> CandidateRouteHop<'a> {
1203 /// Returns the short channel ID for this hop, if one is known.
1205 /// This SCID could be an alias or a globally unique SCID, and thus is only expected to
1206 /// uniquely identify this channel in conjunction with the [`CandidateRouteHop::source`].
1208 /// Returns `Some` as long as the candidate is a [`CandidateRouteHop::PublicHop`], a
1209 /// [`CandidateRouteHop::PrivateHop`] from a BOLT 11 route hint, or a
1210 /// [`CandidateRouteHop::FirstHop`] with a known [`ChannelDetails::get_outbound_payment_scid`]
1211 /// (which is always true for channels which are funded and ready for use).
1213 /// In other words, this should always return `Some` as long as the candidate hop is not a
1214 /// [`CandidateRouteHop::Blinded`] or a [`CandidateRouteHop::OneHopBlinded`].
1216 /// Note that this is deliberately not public as it is somewhat of a footgun because it doesn't
1217 /// define a global namespace.
1219 fn short_channel_id(&self) -> Option<u64> {
1221 CandidateRouteHop::FirstHop { details, .. } => details.get_outbound_payment_scid(),
1222 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1223 CandidateRouteHop::PrivateHop { hint, .. } => Some(hint.short_channel_id),
1224 CandidateRouteHop::Blinded { .. } => None,
1225 CandidateRouteHop::OneHopBlinded { .. } => None,
1229 /// Returns the globally unique short channel ID for this hop, if one is known.
1231 /// This only returns `Some` if the channel is public (either our own, or one we've learned
1232 /// from the public network graph), and thus the short channel ID we have for this channel is
1233 /// globally unique and identifies this channel in a global namespace.
1235 pub fn globally_unique_short_channel_id(&self) -> Option<u64> {
1237 CandidateRouteHop::FirstHop { details, .. } => if details.is_public { details.short_channel_id } else { None },
1238 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1239 CandidateRouteHop::PrivateHop { .. } => None,
1240 CandidateRouteHop::Blinded { .. } => None,
1241 CandidateRouteHop::OneHopBlinded { .. } => None,
1245 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1246 fn features(&self) -> ChannelFeatures {
1248 CandidateRouteHop::FirstHop { details, .. } => details.counterparty.features.to_context(),
1249 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1250 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1251 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1252 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1256 /// Returns the required difference in HTLC CLTV expiry between the [`Self::source`] and the
1257 /// next-hop for an HTLC taking this hop.
1259 /// This is the time that the node(s) in this hop have to claim the HTLC on-chain if the
1260 /// next-hop goes on chain with a payment preimage.
1262 pub fn cltv_expiry_delta(&self) -> u32 {
1264 CandidateRouteHop::FirstHop { .. } => 0,
1265 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1266 CandidateRouteHop::PrivateHop { hint, .. } => hint.cltv_expiry_delta as u32,
1267 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1268 CandidateRouteHop::OneHopBlinded { .. } => 0,
1272 /// Returns the minimum amount that can be sent over this hop, in millisatoshis.
1274 pub fn htlc_minimum_msat(&self) -> u64 {
1276 CandidateRouteHop::FirstHop { details, .. } => details.next_outbound_htlc_minimum_msat,
1277 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1278 CandidateRouteHop::PrivateHop { hint, .. } => hint.htlc_minimum_msat.unwrap_or(0),
1279 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1280 CandidateRouteHop::OneHopBlinded { .. } => 0,
1284 /// Returns the fees that must be paid to route an HTLC over this channel.
1286 pub fn fees(&self) -> RoutingFees {
1288 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1289 base_msat: 0, proportional_millionths: 0,
1291 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1292 CandidateRouteHop::PrivateHop { hint, .. } => hint.fees,
1293 CandidateRouteHop::Blinded { hint, .. } => {
1295 base_msat: hint.0.fee_base_msat,
1296 proportional_millionths: hint.0.fee_proportional_millionths
1299 CandidateRouteHop::OneHopBlinded { .. } =>
1300 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1304 /// Fetch the effective capacity of this hop.
1306 /// Note that this may be somewhat expensive, so calls to this should be limited and results
1308 fn effective_capacity(&self) -> EffectiveCapacity {
1310 CandidateRouteHop::FirstHop { details, .. } => EffectiveCapacity::ExactLiquidity {
1311 liquidity_msat: details.next_outbound_htlc_limit_msat,
1313 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1314 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. } =>
1315 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1316 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. } =>
1317 EffectiveCapacity::Infinite,
1318 CandidateRouteHop::Blinded { hint, .. } =>
1319 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1320 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1324 /// Returns an ID describing the given hop.
1326 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1328 fn id(&self) -> CandidateHopId {
1330 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1331 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1332 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1335 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1337 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1343 /// Returns the source node id of current hop.
1345 /// Source node id refers to the node forwarding the HTLC through this hop.
1347 /// For [`Self::FirstHop`] we return payer's node id.
1349 pub fn source(&self) -> NodeId {
1351 CandidateRouteHop::FirstHop { payer_node_id, .. } => **payer_node_id,
1352 CandidateRouteHop::PublicHop { info, .. } => *info.source(),
1353 CandidateRouteHop::PrivateHop { hint, .. } => hint.src_node_id.into(),
1354 CandidateRouteHop::Blinded { hint, .. } => hint.1.introduction_node_id.into(),
1355 CandidateRouteHop::OneHopBlinded { hint, .. } => hint.1.introduction_node_id.into(),
1358 /// Returns the target node id of this hop, if known.
1360 /// Target node id refers to the node receiving the HTLC after this hop.
1362 /// For [`Self::Blinded`] we return `None` because the ultimate destination after the blinded
1363 /// path is unknown.
1365 /// For [`Self::OneHopBlinded`] we return `None` because the target is the same as the source,
1366 /// and such a return value would be somewhat nonsensical.
1368 pub fn target(&self) -> Option<NodeId> {
1370 CandidateRouteHop::FirstHop { details, .. } => Some(details.counterparty.node_id.into()),
1371 CandidateRouteHop::PublicHop { info, .. } => Some(*info.target()),
1372 CandidateRouteHop::PrivateHop { target_node_id, .. } => Some(**target_node_id),
1373 CandidateRouteHop::Blinded { .. } => None,
1374 CandidateRouteHop::OneHopBlinded { .. } => None,
1379 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1381 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1383 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1384 /// isn't guaranteed to be unique at all.
1386 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1387 /// difficult-to-use API.
1388 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1389 enum CandidateHopId {
1390 /// Contains (scid, src_node_id < target_node_id)
1392 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1397 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1398 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1400 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1401 EffectiveCapacity::Infinite => u64::max_value(),
1402 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1403 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1404 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1405 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1406 // expected to have been generated from up-to-date capacity information.
1407 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1408 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1409 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1413 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1414 -> bool where I1::Item: PartialEq<I2::Item> {
1416 let a = iter_a.next();
1417 let b = iter_b.next();
1418 if a.is_none() && b.is_none() { return true; }
1419 if a.is_none() || b.is_none() { return false; }
1420 if a.unwrap().ne(&b.unwrap()) { return false; }
1424 /// It's useful to keep track of the hops associated with the fees required to use them,
1425 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1426 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1427 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1429 #[repr(C)] // Force fields to appear in the order we define them.
1430 struct PathBuildingHop<'a> {
1431 candidate: CandidateRouteHop<'a>,
1432 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1433 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1434 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1435 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1436 /// avoid processing them again.
1437 was_processed: bool,
1438 /// Used to compare channels when choosing the for routing.
1439 /// Includes paying for the use of a hop and the following hops, as well as
1440 /// an estimated cost of reaching this hop.
1441 /// Might get stale when fees are recomputed. Primarily for internal use.
1442 total_fee_msat: u64,
1443 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1444 /// walk and may be invalid thereafter.
1445 path_htlc_minimum_msat: u64,
1446 /// All penalties incurred from this channel on the way to the destination, as calculated using
1447 /// channel scoring.
1448 path_penalty_msat: u64,
1450 // The last 16 bytes are on the next cache line by default in glibc's malloc. Thus, we should
1451 // only place fields which are not hot there. Luckily, the next three fields are only read if
1452 // we end up on the selected path, and only in the final path layout phase, so we don't care
1453 // too much if reading them is slow.
1457 /// All the fees paid *after* this channel on the way to the destination
1458 next_hops_fee_msat: u64,
1459 /// Fee paid for the use of the current channel (see candidate.fees()).
1460 /// The value will be actually deducted from the counterparty balance on the previous link.
1461 hop_use_fee_msat: u64,
1463 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1464 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1465 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1466 // value_contribution_msat, which requires tracking it here. See comments below where it is
1467 // used for more info.
1468 value_contribution_msat: u64,
1471 // Checks that the entries in the `find_route` `dist` map fit in (exactly) two standard x86-64
1472 // cache lines. Sadly, they're not guaranteed to actually lie on a cache line (and in fact,
1473 // generally won't, because at least glibc's malloc will align to a nice, big, round
1474 // boundary...plus 16), but at least it will reduce the amount of data we'll need to load.
1476 // Note that these assertions only pass on somewhat recent rustc, and thus are gated on the
1479 const _NODE_MAP_SIZE_TWO_CACHE_LINES: usize = 128 - core::mem::size_of::<(NodeId, PathBuildingHop)>();
1481 const _NODE_MAP_SIZE_EXACTLY_CACHE_LINES: usize = core::mem::size_of::<(NodeId, PathBuildingHop)>() - 128;
1483 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1484 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1485 let mut debug_struct = f.debug_struct("PathBuildingHop");
1487 .field("node_id", &self.candidate.target())
1488 .field("short_channel_id", &self.candidate.short_channel_id())
1489 .field("total_fee_msat", &self.total_fee_msat)
1490 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1491 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1492 .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)))
1493 .field("path_penalty_msat", &self.path_penalty_msat)
1494 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1495 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1496 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1497 let debug_struct = debug_struct
1498 .field("value_contribution_msat", &self.value_contribution_msat);
1499 debug_struct.finish()
1503 // Instantiated with a list of hops with correct data in them collected during path finding,
1504 // an instance of this struct should be further modified only via given methods.
1506 struct PaymentPath<'a> {
1507 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1510 impl<'a> PaymentPath<'a> {
1511 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1512 fn get_value_msat(&self) -> u64 {
1513 self.hops.last().unwrap().0.fee_msat
1516 fn get_path_penalty_msat(&self) -> u64 {
1517 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1520 fn get_total_fee_paid_msat(&self) -> u64 {
1521 if self.hops.len() < 1 {
1525 // Can't use next_hops_fee_msat because it gets outdated.
1526 for (i, (hop, _)) in self.hops.iter().enumerate() {
1527 if i != self.hops.len() - 1 {
1528 result += hop.fee_msat;
1534 fn get_cost_msat(&self) -> u64 {
1535 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1538 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1539 // to change fees may result in an inconsistency.
1541 // Sometimes we call this function right after constructing a path which is inconsistent in
1542 // that it the value being transferred has decreased while we were doing path finding, leading
1543 // to the fees being paid not lining up with the actual limits.
1545 // Note that this function is not aware of the available_liquidity limit, and thus does not
1546 // support increasing the value being transferred beyond what was selected during the initial
1549 // Returns the amount that this path contributes to the total payment value, which may be greater
1550 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1551 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1552 let mut extra_contribution_msat = 0;
1553 let mut total_fee_paid_msat = 0 as u64;
1554 for i in (0..self.hops.len()).rev() {
1555 let last_hop = i == self.hops.len() - 1;
1557 // For non-last-hop, this value will represent the fees paid on the current hop. It
1558 // will consist of the fees for the use of the next hop, and extra fees to match
1559 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1560 let mut cur_hop_fees_msat = 0;
1562 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1565 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1566 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1567 cur_hop.path_penalty_msat += extra_contribution_msat;
1568 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1569 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1570 // set it too high just to maliciously take more fees by exploiting this
1571 // match htlc_minimum_msat logic.
1572 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1573 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1574 // Note that there is a risk that *previous hops* (those closer to us, as we go
1575 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1577 // This might make us end up with a broken route, although this should be super-rare
1578 // in practice, both because of how healthy channels look like, and how we pick
1579 // channels in add_entry.
1580 // Also, this can't be exploited more heavily than *announce a free path and fail
1582 cur_hop_transferred_amount_msat += extra_fees_msat;
1584 // We remember and return the extra fees on the final hop to allow accounting for
1585 // them in the path's value contribution.
1587 extra_contribution_msat = extra_fees_msat;
1589 total_fee_paid_msat += extra_fees_msat;
1590 cur_hop_fees_msat += extra_fees_msat;
1595 // Final hop is a special case: it usually has just value_msat (by design), but also
1596 // it still could overpay for the htlc_minimum_msat.
1597 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1599 // Propagate updated fees for the use of the channels to one hop back, where they
1600 // will be actually paid (fee_msat). The last hop is handled above separately.
1601 cur_hop.fee_msat = cur_hop_fees_msat;
1604 // Fee for the use of the current hop which will be deducted on the previous hop.
1605 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1606 // this channel is free for us.
1608 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1609 cur_hop.hop_use_fee_msat = new_fee;
1610 total_fee_paid_msat += new_fee;
1612 // It should not be possible because this function is called only to reduce the
1613 // value. In that case, compute_fee was already called with the same fees for
1614 // larger amount and there was no overflow.
1619 value_msat + extra_contribution_msat
1624 /// Calculate the fees required to route the given amount over a channel with the given fees.
1625 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1626 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1627 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1631 /// Calculate the fees required to route the given amount over a channel with the given fees,
1632 /// saturating to [`u64::max_value`].
1633 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1634 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1635 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1636 .saturating_add(channel_fees.base_msat as u64)
1639 /// The default `features` we assume for a node in a route, when no `features` are known about that
1642 /// Default features are:
1643 /// * variable_length_onion_optional
1644 fn default_node_features() -> NodeFeatures {
1645 let mut features = NodeFeatures::empty();
1646 features.set_variable_length_onion_optional();
1650 struct LoggedPayeePubkey(Option<PublicKey>);
1651 impl fmt::Display for LoggedPayeePubkey {
1652 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1655 "payee node id ".fmt(f)?;
1659 "blinded payee".fmt(f)
1665 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1666 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1667 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1669 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1670 "blinded route hint with introduction node id ".fmt(f)?;
1671 hint.1.introduction_node_id.fmt(f)?;
1672 " and blinding point ".fmt(f)?;
1673 hint.1.blinding_point.fmt(f)
1675 CandidateRouteHop::FirstHop { .. } => {
1676 "first hop with SCID ".fmt(f)?;
1677 self.0.short_channel_id().unwrap().fmt(f)
1679 CandidateRouteHop::PrivateHop { .. } => {
1680 "route hint with SCID ".fmt(f)?;
1681 self.0.short_channel_id().unwrap().fmt(f)
1685 self.0.short_channel_id().unwrap().fmt(f)
1692 fn sort_first_hop_channels(
1693 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1694 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1696 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1697 // most like to use.
1699 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1700 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1703 // Second, because simply always sorting in descending order would always use our largest
1704 // available outbound capacity, needlessly fragmenting our available channel capacities,
1705 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1706 // which have enough, but not too much, capacity for the payment.
1708 // Available outbound balances factor in liquidity already reserved for previously found paths.
1709 channels.sort_unstable_by(|chan_a, chan_b| {
1710 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1711 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1712 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1713 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1714 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1715 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1716 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1717 // Sort in descending order
1718 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1720 // Sort in ascending order
1721 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1726 /// Finds a route from us (payer) to the given target node (payee).
1728 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1729 /// in the given [`RouteParameters::payment_params`].
1730 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1732 /// Private routing paths between a public node and the target may be included in the `payee` field
1733 /// of [`RouteParameters::payment_params`].
1735 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1736 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1737 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1739 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1740 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1741 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1745 /// Panics if first_hops contains channels without `short_channel_id`s;
1746 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1748 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1749 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1750 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1751 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1752 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1753 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1754 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1755 ) -> Result<Route, LightningError>
1756 where L::Target: Logger, GL::Target: Logger {
1757 let graph_lock = network_graph.read_only();
1758 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1759 scorer, score_params, random_seed_bytes)?;
1760 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1764 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1765 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1766 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1767 _random_seed_bytes: &[u8; 32]
1768 ) -> Result<Route, LightningError>
1769 where L::Target: Logger {
1771 let payment_params = &route_params.payment_params;
1772 let final_value_msat = route_params.final_value_msat;
1773 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1774 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1775 // so use a dummy id for this in the blinded case.
1776 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1777 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1778 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1779 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1780 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1782 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1783 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1785 if our_node_id == maybe_dummy_payee_node_id {
1786 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1789 if final_value_msat > MAX_VALUE_MSAT {
1790 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1793 if final_value_msat == 0 {
1794 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1797 match &payment_params.payee {
1798 Payee::Clear { route_hints, node_id, .. } => {
1799 for route in route_hints.iter() {
1800 for hop in &route.0 {
1801 if hop.src_node_id == *node_id {
1802 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1807 Payee::Blinded { route_hints, .. } => {
1808 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1809 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});
1811 for (_, blinded_path) in route_hints.iter() {
1812 if blinded_path.blinded_hops.len() == 0 {
1813 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1814 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1815 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1816 } else if blinded_path.blinded_hops.len() == 1 &&
1817 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1818 && p.introduction_node_id != blinded_path.introduction_node_id)
1820 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1825 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1826 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1827 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});
1830 // The general routing idea is the following:
1831 // 1. Fill first/last hops communicated by the caller.
1832 // 2. Attempt to construct a path from payer to payee for transferring
1833 // any ~sufficient (described later) value.
1834 // If succeed, remember which channels were used and how much liquidity they have available,
1835 // so that future paths don't rely on the same liquidity.
1836 // 3. Proceed to the next step if:
1837 // - we hit the recommended target value;
1838 // - OR if we could not construct a new path. Any next attempt will fail too.
1839 // Otherwise, repeat step 2.
1840 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1841 // (not recommended value).
1842 // 5. If yes, proceed. If not, fail routing.
1843 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1844 // transferred up to the transfer target value.
1845 // 7. Reduce the value of the last path until we are sending only the target value.
1846 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1847 // them so that we're not sending two HTLCs along the same path.
1849 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1850 // distance from the payee
1852 // We are not a faithful Dijkstra's implementation because we can change values which impact
1853 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1854 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1855 // the value we are currently attempting to send over a path, we simply reduce the value being
1856 // sent along the path for any hops after that channel. This may imply that later fees (which
1857 // we've already tabulated) are lower because a smaller value is passing through the channels
1858 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1859 // channels which were selected earlier (and which may still be used for other paths without a
1860 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1863 // One potentially problematic case for this algorithm would be if there are many
1864 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1865 // graph walking), we may never find a path which is not liquidity-limited and has lower
1866 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1867 // Because we only consider paths with at least 5% of the total value being sent, the damage
1868 // from such a case should be limited, however this could be further reduced in the future by
1869 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1870 // limits for the purposes of fee calculation.
1872 // Alternatively, we could store more detailed path information in the heap (targets, below)
1873 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1874 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1875 // and practically (as we would need to store dynamically-allocated path information in heap
1876 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1877 // results of such an algorithm would likely be biased towards lower-value paths.
1879 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1880 // outside of our current search value, running a path search more times to gather candidate
1881 // paths at different values. While this may be acceptable, further path searches may increase
1882 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1883 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1884 // the same time, remaining generic across different payment values.
1886 let network_channels = network_graph.channels();
1887 let network_nodes = network_graph.nodes();
1889 if payment_params.max_path_count == 0 {
1890 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1893 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1894 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1896 let allow_mpp = if payment_params.max_path_count == 1 {
1898 } else if payment_params.payee.supports_basic_mpp() {
1900 } else if let Some(payee) = payee_node_id_opt {
1901 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1902 |info| info.features.supports_basic_mpp()))
1905 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1907 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1908 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1909 if allow_mpp { "with" } else { "without" },
1910 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1911 max_total_routing_fee_msat);
1914 // Prepare the data we'll use for payee-to-payer search by
1915 // inserting first hops suggested by the caller as targets.
1916 // Our search will then attempt to reach them while traversing from the payee node.
1917 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1918 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1919 if let Some(hops) = first_hops {
1921 if chan.get_outbound_payment_scid().is_none() {
1922 panic!("first_hops should be filled in with usable channels, not pending ones");
1924 if chan.counterparty.node_id == *our_node_pubkey {
1925 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1928 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1929 .or_insert(Vec::new())
1932 if first_hop_targets.is_empty() {
1933 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1937 let mut private_hop_key_cache = HashMap::with_capacity(
1938 payment_params.payee.unblinded_route_hints().iter().map(|path| path.0.len()).sum()
1941 // Because we store references to private hop node_ids in `dist`, below, we need them to exist
1942 // (as `NodeId`, not `PublicKey`) for the lifetime of `dist`. Thus, we calculate all the keys
1943 // we'll need here and simply fetch them when routing.
1944 private_hop_key_cache.insert(maybe_dummy_payee_pk, NodeId::from_pubkey(&maybe_dummy_payee_pk));
1945 for route in payment_params.payee.unblinded_route_hints().iter() {
1946 for hop in route.0.iter() {
1947 private_hop_key_cache.insert(hop.src_node_id, NodeId::from_pubkey(&hop.src_node_id));
1951 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1952 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1953 // adding duplicate entries when we find a better path to a given node.
1954 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1956 // Map from node_id to information about the best current path to that node, including feerate
1958 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1960 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1961 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1962 // htlc_minimum with extra fees while still finding a cheaper path.
1963 let mut hit_minimum_limit;
1965 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1966 // We start with a path_value of the exact amount we want, and if that generates a route we may
1967 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1968 // amount we want in total across paths, selecting the best subset at the end.
1969 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1970 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1971 let mut path_value_msat = final_value_msat;
1973 // Routing Fragmentation Mitigation heuristic:
1975 // Routing fragmentation across many payment paths increases the overall routing
1976 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1977 // Taking too many smaller paths also increases the chance of payment failure.
1978 // Thus to avoid this effect, we require from our collected links to provide
1979 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1980 // This requirement is currently set to be 1/max_path_count of the payment
1981 // value to ensure we only ever return routes that do not violate this limit.
1982 let minimal_value_contribution_msat: u64 = if allow_mpp {
1983 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1988 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1989 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1990 // drop the requirement by setting this to 0.
1991 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1993 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1994 // determine if the channel can be used by additional MPP paths or to inform path finding
1995 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1996 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1998 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1999 HashMap::with_capacity(network_nodes.len());
2001 // Keeping track of how much value we already collected across other paths. Helps to decide
2002 // when we want to stop looking for new paths.
2003 let mut already_collected_value_msat = 0;
2005 for (_, channels) in first_hop_targets.iter_mut() {
2006 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
2010 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
2011 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
2013 // Remember how many candidates we ignored to allow for some logging afterwards.
2014 let mut num_ignored_value_contribution: u32 = 0;
2015 let mut num_ignored_path_length_limit: u32 = 0;
2016 let mut num_ignored_cltv_delta_limit: u32 = 0;
2017 let mut num_ignored_previously_failed: u32 = 0;
2018 let mut num_ignored_total_fee_limit: u32 = 0;
2019 let mut num_ignored_avoid_overpayment: u32 = 0;
2020 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
2022 macro_rules! add_entry {
2023 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
2024 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
2025 // since that value has to be transferred over this channel.
2026 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
2027 ( $candidate: expr, $next_hops_fee_msat: expr,
2028 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
2029 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
2030 // We "return" whether we updated the path at the end, and how much we can route via
2031 // this channel, via this:
2032 let mut hop_contribution_amt_msat = None;
2033 // Channels to self should not be used. This is more of belt-and-suspenders, because in
2034 // practice these cases should be caught earlier:
2035 // - for regular channels at channel announcement (TODO)
2036 // - for first and last hops early in get_route
2037 let src_node_id = $candidate.source();
2038 if Some(src_node_id) != $candidate.target() {
2039 let scid_opt = $candidate.short_channel_id();
2040 let effective_capacity = $candidate.effective_capacity();
2041 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
2043 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
2044 // It may be misleading because we might later choose to reduce the value transferred
2045 // over these channels, and the channel which was insufficient might become sufficient.
2046 // Worst case: we drop a good channel here because it can't cover the high following
2047 // fees caused by one expensive channel, but then this channel could have been used
2048 // if the amount being transferred over this path is lower.
2049 // We do this for now, but this is a subject for removal.
2050 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
2051 let used_liquidity_msat = used_liquidities
2052 .get(&$candidate.id())
2053 .map_or(0, |used_liquidity_msat| {
2054 available_value_contribution_msat = available_value_contribution_msat
2055 .saturating_sub(*used_liquidity_msat);
2056 *used_liquidity_msat
2059 // Verify the liquidity offered by this channel complies to the minimal contribution.
2060 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
2061 // Do not consider candidate hops that would exceed the maximum path length.
2062 let path_length_to_node = $next_hops_path_length + 1;
2063 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
2065 // Do not consider candidates that exceed the maximum total cltv expiry limit.
2066 // In order to already account for some of the privacy enhancing random CLTV
2067 // expiry delta offset we add on top later, we subtract a rough estimate
2068 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
2069 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
2070 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
2071 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
2072 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
2073 .saturating_add($candidate.cltv_expiry_delta());
2074 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
2076 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
2077 // Includes paying fees for the use of the following channels.
2078 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
2079 Some(result) => result,
2080 // Can't overflow due to how the values were computed right above.
2081 None => unreachable!(),
2083 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2084 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
2085 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
2087 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2088 let may_overpay_to_meet_path_minimum_msat =
2089 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
2090 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
2091 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
2092 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
2094 let payment_failed_on_this_channel = scid_opt.map_or(false,
2095 |scid| payment_params.previously_failed_channels.contains(&scid));
2097 let (should_log_candidate, first_hop_details) = match $candidate {
2098 CandidateRouteHop::FirstHop { details, .. } => (true, Some(details)),
2099 CandidateRouteHop::PrivateHop { .. } => (true, None),
2100 CandidateRouteHop::Blinded { .. } => (true, None),
2101 CandidateRouteHop::OneHopBlinded { .. } => (true, None),
2105 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
2106 // bother considering this channel. If retrying with recommended_value_msat may
2107 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
2108 // around again with a higher amount.
2109 if !contributes_sufficient_value {
2110 if should_log_candidate {
2111 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
2113 if let Some(details) = first_hop_details {
2115 "First hop candidate next_outbound_htlc_limit_msat: {}",
2116 details.next_outbound_htlc_limit_msat,
2120 num_ignored_value_contribution += 1;
2121 } else if exceeds_max_path_length {
2122 if should_log_candidate {
2123 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
2125 num_ignored_path_length_limit += 1;
2126 } else if exceeds_cltv_delta_limit {
2127 if should_log_candidate {
2128 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
2130 if let Some(_) = first_hop_details {
2132 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
2133 hop_total_cltv_delta,
2134 max_total_cltv_expiry_delta,
2138 num_ignored_cltv_delta_limit += 1;
2139 } else if payment_failed_on_this_channel {
2140 if should_log_candidate {
2141 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
2143 num_ignored_previously_failed += 1;
2144 } else if may_overpay_to_meet_path_minimum_msat {
2145 if should_log_candidate {
2147 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
2148 LoggedCandidateHop(&$candidate));
2150 if let Some(details) = first_hop_details {
2152 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2153 details.next_outbound_htlc_minimum_msat,
2157 num_ignored_avoid_overpayment += 1;
2158 hit_minimum_limit = true;
2159 } else if over_path_minimum_msat {
2160 // Note that low contribution here (limited by available_liquidity_msat)
2161 // might violate htlc_minimum_msat on the hops which are next along the
2162 // payment path (upstream to the payee). To avoid that, we recompute
2163 // path fees knowing the final path contribution after constructing it.
2164 let curr_min = cmp::max(
2165 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2167 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2168 .saturating_add(curr_min);
2169 let hm_entry = dist.entry(src_node_id);
2170 let old_entry = hm_entry.or_insert_with(|| {
2171 // If there was previously no known way to access the source node
2172 // (recall it goes payee-to-payer) of short_channel_id, first add a
2173 // semi-dummy record just to compute the fees to reach the source node.
2174 // This will affect our decision on selecting short_channel_id
2175 // as a way to reach the $candidate.target() node.
2177 candidate: $candidate.clone(),
2179 next_hops_fee_msat: u64::max_value(),
2180 hop_use_fee_msat: u64::max_value(),
2181 total_fee_msat: u64::max_value(),
2182 path_htlc_minimum_msat,
2183 path_penalty_msat: u64::max_value(),
2184 was_processed: false,
2185 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2186 value_contribution_msat,
2190 #[allow(unused_mut)] // We only use the mut in cfg(test)
2191 let mut should_process = !old_entry.was_processed;
2192 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2194 // In test/fuzzing builds, we do extra checks to make sure the skipping
2195 // of already-seen nodes only happens in cases we expect (see below).
2196 if !should_process { should_process = true; }
2200 let mut hop_use_fee_msat = 0;
2201 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2203 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2204 // will have the same effective-fee
2205 if src_node_id != our_node_id {
2206 // Note that `u64::max_value` means we'll always fail the
2207 // `old_entry.total_fee_msat > total_fee_msat` check below
2208 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2209 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2212 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2213 if total_fee_msat > max_total_routing_fee_msat {
2214 if should_log_candidate {
2215 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2217 if let Some(_) = first_hop_details {
2219 "First hop candidate routing fee: {}. Limit: {}",
2221 max_total_routing_fee_msat,
2225 num_ignored_total_fee_limit += 1;
2227 let channel_usage = ChannelUsage {
2228 amount_msat: amount_to_transfer_over_msat,
2229 inflight_htlc_msat: used_liquidity_msat,
2232 let channel_penalty_msat =
2233 scorer.channel_penalty_msat($candidate,
2236 let path_penalty_msat = $next_hops_path_penalty_msat
2237 .saturating_add(channel_penalty_msat);
2239 // Update the way of reaching $candidate.source()
2240 // with the given short_channel_id (from $candidate.target()),
2241 // if this way is cheaper than the already known
2242 // (considering the cost to "reach" this channel from the route destination,
2243 // the cost of using this channel,
2244 // and the cost of routing to the source node of this channel).
2245 // Also, consider that htlc_minimum_msat_difference, because we might end up
2246 // paying it. Consider the following exploit:
2247 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2248 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2249 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2250 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2252 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2253 // but it may require additional tracking - we don't want to double-count
2254 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2255 // can't use something that may decrease on future hops.
2256 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2257 .saturating_add(old_entry.path_penalty_msat);
2258 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2259 .saturating_add(path_penalty_msat);
2261 if !old_entry.was_processed && new_cost < old_cost {
2262 let new_graph_node = RouteGraphNode {
2263 node_id: src_node_id,
2264 score: cmp::max(total_fee_msat, path_htlc_minimum_msat).saturating_add(path_penalty_msat),
2265 total_cltv_delta: hop_total_cltv_delta,
2266 value_contribution_msat,
2267 path_length_to_node,
2269 targets.push(new_graph_node);
2270 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2271 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2272 old_entry.total_fee_msat = total_fee_msat;
2273 old_entry.candidate = $candidate.clone();
2274 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2275 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2276 old_entry.path_penalty_msat = path_penalty_msat;
2277 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2279 old_entry.value_contribution_msat = value_contribution_msat;
2281 hop_contribution_amt_msat = Some(value_contribution_msat);
2282 } else if old_entry.was_processed && new_cost < old_cost {
2283 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2285 // If we're skipping processing a node which was previously
2286 // processed even though we found another path to it with a
2287 // cheaper fee, check that it was because the second path we
2288 // found (which we are processing now) has a lower value
2289 // contribution due to an HTLC minimum limit.
2291 // e.g. take a graph with two paths from node 1 to node 2, one
2292 // through channel A, and one through channel B. Channel A and
2293 // B are both in the to-process heap, with their scores set by
2294 // a higher htlc_minimum than fee.
2295 // Channel A is processed first, and the channels onwards from
2296 // node 1 are added to the to-process heap. Thereafter, we pop
2297 // Channel B off of the heap, note that it has a much more
2298 // restrictive htlc_maximum_msat, and recalculate the fees for
2299 // all of node 1's channels using the new, reduced, amount.
2301 // This would be bogus - we'd be selecting a higher-fee path
2302 // with a lower htlc_maximum_msat instead of the one we'd
2303 // already decided to use.
2304 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2306 value_contribution_msat + path_penalty_msat <
2307 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2314 if should_log_candidate {
2316 "Ignoring {} due to its htlc_minimum_msat limit.",
2317 LoggedCandidateHop(&$candidate));
2319 if let Some(details) = first_hop_details {
2321 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2322 details.next_outbound_htlc_minimum_msat,
2326 num_ignored_htlc_minimum_msat_limit += 1;
2330 hop_contribution_amt_msat
2334 let default_node_features = default_node_features();
2336 // Find ways (channels with destination) to reach a given node and store them
2337 // in the corresponding data structures (routing graph etc).
2338 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2339 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2340 // This data can later be helpful to optimize routing (pay lower fees).
2341 macro_rules! add_entries_to_cheapest_to_target_node {
2342 ( $node: expr, $node_id: expr, $next_hops_value_contribution: expr,
2343 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2344 let fee_to_target_msat;
2345 let next_hops_path_htlc_minimum_msat;
2346 let next_hops_path_penalty_msat;
2347 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2348 let was_processed = elem.was_processed;
2349 elem.was_processed = true;
2350 fee_to_target_msat = elem.total_fee_msat;
2351 next_hops_path_htlc_minimum_msat = elem.path_htlc_minimum_msat;
2352 next_hops_path_penalty_msat = elem.path_penalty_msat;
2355 // Entries are added to dist in add_entry!() when there is a channel from a node.
2356 // Because there are no channels from payee, it will not have a dist entry at this point.
2357 // If we're processing any other node, it is always be the result of a channel from it.
2358 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2359 fee_to_target_msat = 0;
2360 next_hops_path_htlc_minimum_msat = 0;
2361 next_hops_path_penalty_msat = 0;
2366 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2367 for details in first_channels {
2368 let candidate = CandidateRouteHop::FirstHop {
2369 details, payer_node_id: &our_node_id,
2371 add_entry!(&candidate, fee_to_target_msat,
2372 $next_hops_value_contribution,
2373 next_hops_path_htlc_minimum_msat, next_hops_path_penalty_msat,
2374 $next_hops_cltv_delta, $next_hops_path_length);
2378 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2381 &default_node_features
2384 if !features.requires_unknown_bits() {
2385 for chan_id in $node.channels.iter() {
2386 let chan = network_channels.get(chan_id).unwrap();
2387 if !chan.features.requires_unknown_bits() {
2388 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2389 if first_hops.is_none() || *source != our_node_id {
2390 if directed_channel.direction().enabled {
2391 let candidate = CandidateRouteHop::PublicHop {
2392 info: directed_channel,
2393 short_channel_id: *chan_id,
2395 add_entry!(&candidate,
2397 $next_hops_value_contribution,
2398 next_hops_path_htlc_minimum_msat,
2399 next_hops_path_penalty_msat,
2400 $next_hops_cltv_delta, $next_hops_path_length);
2411 let mut payment_paths = Vec::<PaymentPath>::new();
2413 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2414 'paths_collection: loop {
2415 // For every new path, start from scratch, except for used_liquidities, which
2416 // helps to avoid reusing previously selected paths in future iterations.
2419 hit_minimum_limit = false;
2421 // If first hop is a private channel and the only way to reach the payee, this is the only
2422 // place where it could be added.
2423 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2424 for details in first_channels {
2425 let candidate = CandidateRouteHop::FirstHop {
2426 details, payer_node_id: &our_node_id,
2428 let added = add_entry!(&candidate, 0, path_value_msat,
2429 0, 0u64, 0, 0).is_some();
2430 log_trace!(logger, "{} direct route to payee via {}",
2431 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2435 // Add the payee as a target, so that the payee-to-payer
2436 // search algorithm knows what to start with.
2437 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2438 // The payee is not in our network graph, so nothing to add here.
2439 // There is still a chance of reaching them via last_hops though,
2440 // so don't yet fail the payment here.
2441 // If not, targets.pop() will not even let us enter the loop in step 2.
2444 add_entries_to_cheapest_to_target_node!(node, payee, path_value_msat, 0, 0);
2449 // If a caller provided us with last hops, add them to routing targets. Since this happens
2450 // earlier than general path finding, they will be somewhat prioritized, although currently
2451 // it matters only if the fees are exactly the same.
2452 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2453 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2454 let have_intro_node_in_graph =
2455 // Only add the hops in this route to our candidate set if either
2456 // we have a direct channel to the first hop or the first hop is
2457 // in the regular network graph.
2458 first_hop_targets.get(&intro_node_id).is_some() ||
2459 network_nodes.get(&intro_node_id).is_some();
2460 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2461 let candidate = if hint.1.blinded_hops.len() == 1 {
2462 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2463 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2464 let mut path_contribution_msat = path_value_msat;
2465 if let Some(hop_used_msat) = add_entry!(&candidate,
2466 0, path_contribution_msat, 0, 0_u64, 0, 0)
2468 path_contribution_msat = hop_used_msat;
2470 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2471 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2473 for details in first_channels {
2474 let first_hop_candidate = CandidateRouteHop::FirstHop {
2475 details, payer_node_id: &our_node_id,
2477 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2481 let path_min = candidate.htlc_minimum_msat().saturating_add(
2482 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2483 add_entry!(&first_hop_candidate, blinded_path_fee,
2484 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2485 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2489 for route in payment_params.payee.unblinded_route_hints().iter()
2490 .filter(|route| !route.0.is_empty())
2492 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2493 let first_hop_src_is_reachable =
2494 // Only add the hops in this route to our candidate set if either we are part of
2495 // the first hop, we have a direct channel to the first hop, or the first hop is in
2496 // the regular network graph.
2497 our_node_id == first_hop_src_id ||
2498 first_hop_targets.get(&first_hop_src_id).is_some() ||
2499 network_nodes.get(&first_hop_src_id).is_some();
2500 if first_hop_src_is_reachable {
2501 // We start building the path from reverse, i.e., from payee
2502 // to the first RouteHintHop in the path.
2503 let hop_iter = route.0.iter().rev();
2504 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2505 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2506 let mut hop_used = true;
2507 let mut aggregate_next_hops_fee_msat: u64 = 0;
2508 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2509 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2510 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2511 let mut aggregate_next_hops_path_length: u8 = 0;
2512 let mut aggregate_path_contribution_msat = path_value_msat;
2514 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2515 let target = private_hop_key_cache.get(&prev_hop_id).unwrap();
2517 if let Some(first_channels) = first_hop_targets.get(&target) {
2518 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2519 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2520 hop.short_channel_id);
2525 let candidate = network_channels
2526 .get(&hop.short_channel_id)
2527 .and_then(|channel| channel.as_directed_to(&target))
2528 .map(|(info, _)| CandidateRouteHop::PublicHop {
2530 short_channel_id: hop.short_channel_id,
2532 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop, target_node_id: target });
2534 if let Some(hop_used_msat) = add_entry!(&candidate,
2535 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2536 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2537 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2539 aggregate_path_contribution_msat = hop_used_msat;
2541 // If this hop was not used then there is no use checking the preceding
2542 // hops in the RouteHint. We can break by just searching for a direct
2543 // channel between last checked hop and first_hop_targets.
2547 let used_liquidity_msat = used_liquidities
2548 .get(&candidate.id()).copied()
2550 let channel_usage = ChannelUsage {
2551 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2552 inflight_htlc_msat: used_liquidity_msat,
2553 effective_capacity: candidate.effective_capacity(),
2555 let channel_penalty_msat = scorer.channel_penalty_msat(
2556 &candidate, channel_usage, score_params
2558 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2559 .saturating_add(channel_penalty_msat);
2561 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2562 .saturating_add(hop.cltv_expiry_delta as u32);
2564 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2567 // Searching for a direct channel between last checked hop and first_hop_targets
2568 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2569 sort_first_hop_channels(first_channels, &used_liquidities,
2570 recommended_value_msat, our_node_pubkey);
2571 for details in first_channels {
2572 let first_hop_candidate = CandidateRouteHop::FirstHop {
2573 details, payer_node_id: &our_node_id,
2575 add_entry!(&first_hop_candidate,
2576 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2577 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2578 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2586 // In the next values of the iterator, the aggregate fees already reflects
2587 // the sum of value sent from payer (final_value_msat) and routing fees
2588 // for the last node in the RouteHint. We need to just add the fees to
2589 // route through the current node so that the preceding node (next iteration)
2591 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2592 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2593 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2595 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2596 // this route hint's source node to forward said min over this channel.
2597 aggregate_next_hops_path_htlc_minimum_msat = {
2598 let curr_htlc_min = cmp::max(
2599 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2601 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2602 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2605 if idx == route.0.len() - 1 {
2606 // The last hop in this iterator is the first hop in
2607 // overall RouteHint.
2608 // If this hop connects to a node with which we have a direct channel,
2609 // ignore the network graph and, if the last hop was added, add our
2610 // direct channel to the candidate set.
2612 // Note that we *must* check if the last hop was added as `add_entry`
2613 // always assumes that the third argument is a node to which we have a
2615 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2616 sort_first_hop_channels(first_channels, &used_liquidities,
2617 recommended_value_msat, our_node_pubkey);
2618 for details in first_channels {
2619 let first_hop_candidate = CandidateRouteHop::FirstHop {
2620 details, payer_node_id: &our_node_id,
2622 add_entry!(&first_hop_candidate,
2623 aggregate_next_hops_fee_msat,
2624 aggregate_path_contribution_msat,
2625 aggregate_next_hops_path_htlc_minimum_msat,
2626 aggregate_next_hops_path_penalty_msat,
2627 aggregate_next_hops_cltv_delta,
2628 aggregate_next_hops_path_length);
2636 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2638 // At this point, targets are filled with the data from first and
2639 // last hops communicated by the caller, and the payment receiver.
2640 let mut found_new_path = false;
2643 // If this loop terminates due the exhaustion of targets, two situations are possible:
2644 // - not enough outgoing liquidity:
2645 // 0 < already_collected_value_msat < final_value_msat
2646 // - enough outgoing liquidity:
2647 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2648 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2649 // paths_collection will be stopped because found_new_path==false.
2650 // This is not necessarily a routing failure.
2651 'path_construction: while let Some(RouteGraphNode { node_id, total_cltv_delta, mut value_contribution_msat, path_length_to_node, .. }) = targets.pop() {
2653 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2654 // traversing the graph and arrange the path out of what we found.
2655 if node_id == our_node_id {
2656 let mut new_entry = dist.remove(&our_node_id).unwrap();
2657 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2660 let mut features_set = false;
2661 let target = ordered_hops.last().unwrap().0.candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2662 if let Some(first_channels) = first_hop_targets.get(&target) {
2663 for details in first_channels {
2664 if let CandidateRouteHop::FirstHop { details: last_hop_details, .. }
2665 = ordered_hops.last().unwrap().0.candidate
2667 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2668 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2669 features_set = true;
2676 if let Some(node) = network_nodes.get(&target) {
2677 if let Some(node_info) = node.announcement_info.as_ref() {
2678 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2680 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2683 // We can fill in features for everything except hops which were
2684 // provided via the invoice we're paying. We could guess based on the
2685 // recipient's features but for now we simply avoid guessing at all.
2689 // Means we succesfully traversed from the payer to the payee, now
2690 // save this path for the payment route. Also, update the liquidity
2691 // remaining on the used hops, so that we take them into account
2692 // while looking for more paths.
2693 if target == maybe_dummy_payee_node_id {
2697 new_entry = match dist.remove(&target) {
2698 Some(payment_hop) => payment_hop,
2699 // We can't arrive at None because, if we ever add an entry to targets,
2700 // we also fill in the entry in dist (see add_entry!).
2701 None => unreachable!(),
2703 // We "propagate" the fees one hop backward (topologically) here,
2704 // so that fees paid for a HTLC forwarding on the current channel are
2705 // associated with the previous channel (where they will be subtracted).
2706 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2707 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2709 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2710 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2712 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2713 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2715 let mut payment_path = PaymentPath {hops: ordered_hops};
2717 // We could have possibly constructed a slightly inconsistent path: since we reduce
2718 // value being transferred along the way, we could have violated htlc_minimum_msat
2719 // on some channels we already passed (assuming dest->source direction). Here, we
2720 // recompute the fees again, so that if that's the case, we match the currently
2721 // underpaid htlc_minimum_msat with fees.
2722 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2723 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2724 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2726 // Since a path allows to transfer as much value as
2727 // the smallest channel it has ("bottleneck"), we should recompute
2728 // the fees so sender HTLC don't overpay fees when traversing
2729 // larger channels than the bottleneck. This may happen because
2730 // when we were selecting those channels we were not aware how much value
2731 // this path will transfer, and the relative fee for them
2732 // might have been computed considering a larger value.
2733 // Remember that we used these channels so that we don't rely
2734 // on the same liquidity in future paths.
2735 let mut prevented_redundant_path_selection = false;
2736 for (hop, _) in payment_path.hops.iter() {
2737 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2738 let used_liquidity_msat = used_liquidities
2739 .entry(hop.candidate.id())
2740 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2741 .or_insert(spent_on_hop_msat);
2742 let hop_capacity = hop.candidate.effective_capacity();
2743 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2744 if *used_liquidity_msat == hop_max_msat {
2745 // If this path used all of this channel's available liquidity, we know
2746 // this path will not be selected again in the next loop iteration.
2747 prevented_redundant_path_selection = true;
2749 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2751 if !prevented_redundant_path_selection {
2752 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2753 // we'll probably end up picking the same path again on the next iteration.
2754 // Decrease the available liquidity of a hop in the middle of the path.
2755 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2756 let exhausted = u64::max_value();
2758 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2759 LoggedCandidateHop(victim_candidate));
2760 if let Some(scid) = victim_candidate.short_channel_id() {
2761 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2762 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2766 // Track the total amount all our collected paths allow to send so that we know
2767 // when to stop looking for more paths
2768 already_collected_value_msat += value_contribution_msat;
2770 payment_paths.push(payment_path);
2771 found_new_path = true;
2772 break 'path_construction;
2775 // If we found a path back to the payee, we shouldn't try to process it again. This is
2776 // the equivalent of the `elem.was_processed` check in
2777 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2778 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2780 // Otherwise, since the current target node is not us,
2781 // keep "unrolling" the payment graph from payee to payer by
2782 // finding a way to reach the current target from the payer side.
2783 match network_nodes.get(&node_id) {
2786 add_entries_to_cheapest_to_target_node!(node, node_id,
2787 value_contribution_msat,
2788 total_cltv_delta, path_length_to_node);
2794 if !found_new_path && channel_saturation_pow_half != 0 {
2795 channel_saturation_pow_half = 0;
2796 continue 'paths_collection;
2798 // If we don't support MPP, no use trying to gather more value ever.
2799 break 'paths_collection;
2803 // Stop either when the recommended value is reached or if no new path was found in this
2805 // In the latter case, making another path finding attempt won't help,
2806 // because we deterministically terminated the search due to low liquidity.
2807 if !found_new_path && channel_saturation_pow_half != 0 {
2808 channel_saturation_pow_half = 0;
2809 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2810 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2811 path_value_msat = recommended_value_msat;
2812 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2813 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2814 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2815 break 'paths_collection;
2816 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2817 // Further, if this was our first walk of the graph, and we weren't limited by an
2818 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2819 // limited by an htlc_minimum_msat value, find another path with a higher value,
2820 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2821 // still keeping a lower total fee than this path.
2822 if !hit_minimum_limit {
2823 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2824 break 'paths_collection;
2826 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.");
2827 path_value_msat = recommended_value_msat;
2831 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2832 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2833 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2834 num_ignored_total_fee_limit;
2835 if num_ignored_total > 0 {
2837 "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.",
2838 num_ignored_value_contribution, num_ignored_path_length_limit,
2839 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2840 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2841 num_ignored_total_fee_limit, num_ignored_total);
2845 if payment_paths.len() == 0 {
2846 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2849 if already_collected_value_msat < final_value_msat {
2850 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2854 let mut selected_route = payment_paths;
2856 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2857 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2859 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2860 // the value they contribute towards the payment amount.
2861 // We sort in descending order as we will remove from the front in `retain`, next.
2862 selected_route.sort_unstable_by(|a, b|
2863 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2864 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2867 // We should make sure that at least 1 path left.
2868 let mut paths_left = selected_route.len();
2869 selected_route.retain(|path| {
2870 if paths_left == 1 {
2873 let path_value_msat = path.get_value_msat();
2874 if path_value_msat <= overpaid_value_msat {
2875 overpaid_value_msat -= path_value_msat;
2881 debug_assert!(selected_route.len() > 0);
2883 if overpaid_value_msat != 0 {
2885 // Now, subtract the remaining overpaid value from the most-expensive path.
2886 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2887 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2888 selected_route.sort_unstable_by(|a, b| {
2889 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2890 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2891 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2893 let expensive_payment_path = selected_route.first_mut().unwrap();
2895 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2896 // can't go negative.
2897 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2898 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2902 // Sort by the path itself and combine redundant paths.
2903 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2904 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2906 selected_route.sort_unstable_by_key(|path| {
2907 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2908 debug_assert!(path.hops.len() <= key.len());
2909 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
2914 for idx in 0..(selected_route.len() - 1) {
2915 if idx + 1 >= selected_route.len() { break; }
2916 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
2917 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
2918 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2919 selected_route[idx].update_value_and_recompute_fees(new_value);
2920 selected_route.remove(idx + 1);
2924 let mut paths = Vec::new();
2925 for payment_path in selected_route {
2926 let mut hops = Vec::with_capacity(payment_path.hops.len());
2927 for (hop, node_features) in payment_path.hops.iter()
2928 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2930 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
2931 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2932 // If we sourced the hop from the graph we're sure the target node is announced.
2934 } else if let CandidateRouteHop::FirstHop { details, .. } = hop.candidate {
2935 // If this is a first hop we also know if it's announced.
2938 // If we sourced it any other way, we double-check the network graph to see if
2939 // there are announced channels between the endpoints. If so, the hop might be
2940 // referring to any of the announced channels, as its `short_channel_id` might be
2941 // an alias, in which case we don't take any chances here.
2942 network_graph.node(&target).map_or(false, |hop_node|
2943 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2944 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
2948 hops.push(RouteHop {
2949 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2950 node_features: node_features.clone(),
2951 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2952 channel_features: hop.candidate.features(),
2953 fee_msat: hop.fee_msat,
2954 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2955 maybe_announced_channel,
2958 let mut final_cltv_delta = final_cltv_expiry_delta;
2959 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2960 if let Some(blinded_path) = h.candidate.blinded_path() {
2961 final_cltv_delta = h.candidate.cltv_expiry_delta();
2963 hops: blinded_path.blinded_hops.clone(),
2964 blinding_point: blinded_path.blinding_point,
2965 excess_final_cltv_expiry_delta: 0,
2966 final_value_msat: h.fee_msat,
2970 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2971 // applicable for the previous hop.
2972 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2973 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2976 paths.push(Path { hops, blinded_tail });
2978 // Make sure we would never create a route with more paths than we allow.
2979 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2981 if let Some(node_features) = payment_params.payee.node_features() {
2982 for path in paths.iter_mut() {
2983 path.hops.last_mut().unwrap().node_features = node_features.clone();
2987 let route = Route { paths, route_params: Some(route_params.clone()) };
2989 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2990 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2991 if route.get_total_fees() > max_total_routing_fee_msat {
2992 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2993 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2997 log_info!(logger, "Got route: {}", log_route!(route));
3001 // When an adversarial intermediary node observes a payment, it may be able to infer its
3002 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
3003 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
3004 // payment path by adding a randomized 'shadow route' offset to the final hop.
3005 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
3006 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
3008 let network_channels = network_graph.channels();
3009 let network_nodes = network_graph.nodes();
3011 for path in route.paths.iter_mut() {
3012 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
3014 // Remember the last three nodes of the random walk and avoid looping back on them.
3015 // Init with the last three nodes from the actual path, if possible.
3016 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
3017 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
3018 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
3020 // Choose the last publicly known node as the starting point for the random walk.
3021 let mut cur_hop: Option<NodeId> = None;
3022 let mut path_nonce = [0u8; 12];
3023 if let Some(starting_hop) = path.hops.iter().rev()
3024 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
3025 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
3026 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
3029 // Init PRNG with the path-dependant nonce, which is static for private paths.
3030 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
3031 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
3033 // Pick a random path length in [1 .. 3]
3034 prng.process_in_place(&mut random_path_bytes);
3035 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
3037 for random_hop in 0..random_walk_length {
3038 // If we don't find a suitable offset in the public network graph, we default to
3039 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3040 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
3042 if let Some(cur_node_id) = cur_hop {
3043 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
3044 // Randomly choose the next unvisited hop.
3045 prng.process_in_place(&mut random_path_bytes);
3046 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
3047 .checked_rem(cur_node.channels.len())
3048 .and_then(|index| cur_node.channels.get(index))
3049 .and_then(|id| network_channels.get(id)) {
3050 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
3051 if !nodes_to_avoid.iter().any(|x| x == next_id) {
3052 nodes_to_avoid[random_hop] = *next_id;
3053 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
3054 cur_hop = Some(*next_id);
3061 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
3062 .checked_add(random_hop_offset)
3063 .unwrap_or(shadow_ctlv_expiry_delta_offset);
3066 // Limit the total offset to reduce the worst-case locked liquidity timevalue
3067 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
3068 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
3070 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
3071 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3072 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
3073 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
3074 max_path_offset = cmp::max(
3075 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
3076 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
3077 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
3079 // Add 'shadow' CLTV offset to the final hop
3080 if let Some(tail) = path.blinded_tail.as_mut() {
3081 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
3082 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
3084 if let Some(last_hop) = path.hops.last_mut() {
3085 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
3086 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
3091 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
3092 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
3094 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
3095 pub fn build_route_from_hops<L: Deref, GL: Deref>(
3096 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3097 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
3098 ) -> Result<Route, LightningError>
3099 where L::Target: Logger, GL::Target: Logger {
3100 let graph_lock = network_graph.read_only();
3101 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
3102 &graph_lock, logger, random_seed_bytes)?;
3103 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
3107 fn build_route_from_hops_internal<L: Deref>(
3108 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3109 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
3110 ) -> Result<Route, LightningError> where L::Target: Logger {
3113 our_node_id: NodeId,
3114 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
3117 impl ScoreLookUp for HopScorer {
3118 type ScoreParams = ();
3119 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
3120 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
3122 let mut cur_id = self.our_node_id;
3123 for i in 0..self.hop_ids.len() {
3124 if let Some(next_id) = self.hop_ids[i] {
3125 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
3137 impl<'a> Writeable for HopScorer {
3139 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
3144 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
3145 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
3148 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
3149 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
3150 for i in 0..hops.len() {
3151 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
3154 let scorer = HopScorer { our_node_id, hop_ids };
3156 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
3161 use crate::blinded_path::{BlindedHop, BlindedPath};
3162 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
3163 use crate::routing::utxo::UtxoResult;
3164 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
3165 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3166 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop};
3167 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3168 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3169 use crate::chain::transaction::OutPoint;
3170 use crate::sign::EntropySource;
3171 use crate::ln::ChannelId;
3172 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3173 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3174 use crate::ln::channelmanager;
3175 use crate::offers::invoice::BlindedPayInfo;
3176 use crate::util::config::UserConfig;
3177 use crate::util::test_utils as ln_test_utils;
3178 use crate::util::chacha20::ChaCha20;
3179 use crate::util::ser::{Readable, Writeable};
3181 use crate::util::ser::Writer;
3183 use bitcoin::hashes::Hash;
3184 use bitcoin::network::constants::Network;
3185 use bitcoin::blockdata::constants::ChainHash;
3186 use bitcoin::blockdata::script::Builder;
3187 use bitcoin::blockdata::opcodes;
3188 use bitcoin::blockdata::transaction::TxOut;
3189 use bitcoin::hashes::hex::FromHex;
3190 use bitcoin::secp256k1::{PublicKey,SecretKey};
3191 use bitcoin::secp256k1::Secp256k1;
3193 use crate::io::Cursor;
3194 use crate::prelude::*;
3195 use crate::sync::Arc;
3197 use core::convert::TryInto;
3199 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3200 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
3201 channelmanager::ChannelDetails {
3202 channel_id: ChannelId::new_zero(),
3203 counterparty: channelmanager::ChannelCounterparty {
3206 unspendable_punishment_reserve: 0,
3207 forwarding_info: None,
3208 outbound_htlc_minimum_msat: None,
3209 outbound_htlc_maximum_msat: None,
3211 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3214 outbound_scid_alias: None,
3215 inbound_scid_alias: None,
3216 channel_value_satoshis: 0,
3219 outbound_capacity_msat,
3220 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3221 next_outbound_htlc_minimum_msat: 0,
3222 inbound_capacity_msat: 42,
3223 unspendable_punishment_reserve: None,
3224 confirmations_required: None,
3225 confirmations: None,
3226 force_close_spend_delay: None,
3227 is_outbound: true, is_channel_ready: true,
3228 is_usable: true, is_public: true,
3229 inbound_htlc_minimum_msat: None,
3230 inbound_htlc_maximum_msat: None,
3232 feerate_sat_per_1000_weight: None,
3233 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
3238 fn simple_route_test() {
3239 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3240 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3241 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3242 let scorer = ln_test_utils::TestScorer::new();
3243 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3244 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3246 // Simple route to 2 via 1
3248 let route_params = RouteParameters::from_payment_params_and_value(
3249 payment_params.clone(), 0);
3250 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3251 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3252 &Default::default(), &random_seed_bytes) {
3253 assert_eq!(err, "Cannot send a payment of 0 msat");
3254 } else { panic!(); }
3256 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3257 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3258 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3259 assert_eq!(route.paths[0].hops.len(), 2);
3261 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3262 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3263 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3264 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3265 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3266 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3268 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3269 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3270 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3271 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3272 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3273 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3277 fn invalid_first_hop_test() {
3278 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3279 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3280 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3281 let scorer = ln_test_utils::TestScorer::new();
3282 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3283 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3285 // Simple route to 2 via 1
3287 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3289 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3290 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3291 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3292 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3293 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3294 } else { panic!(); }
3296 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3297 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3298 assert_eq!(route.paths[0].hops.len(), 2);
3302 fn htlc_minimum_test() {
3303 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3304 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3305 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3306 let scorer = ln_test_utils::TestScorer::new();
3307 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3308 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3310 // Simple route to 2 via 1
3312 // Disable other paths
3313 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3314 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3315 short_channel_id: 12,
3317 flags: 2, // to disable
3318 cltv_expiry_delta: 0,
3319 htlc_minimum_msat: 0,
3320 htlc_maximum_msat: MAX_VALUE_MSAT,
3322 fee_proportional_millionths: 0,
3323 excess_data: Vec::new()
3325 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3326 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3327 short_channel_id: 3,
3329 flags: 2, // to disable
3330 cltv_expiry_delta: 0,
3331 htlc_minimum_msat: 0,
3332 htlc_maximum_msat: MAX_VALUE_MSAT,
3334 fee_proportional_millionths: 0,
3335 excess_data: Vec::new()
3337 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3338 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3339 short_channel_id: 13,
3341 flags: 2, // to disable
3342 cltv_expiry_delta: 0,
3343 htlc_minimum_msat: 0,
3344 htlc_maximum_msat: MAX_VALUE_MSAT,
3346 fee_proportional_millionths: 0,
3347 excess_data: Vec::new()
3349 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3350 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3351 short_channel_id: 6,
3353 flags: 2, // to disable
3354 cltv_expiry_delta: 0,
3355 htlc_minimum_msat: 0,
3356 htlc_maximum_msat: MAX_VALUE_MSAT,
3358 fee_proportional_millionths: 0,
3359 excess_data: Vec::new()
3361 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3362 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3363 short_channel_id: 7,
3365 flags: 2, // to disable
3366 cltv_expiry_delta: 0,
3367 htlc_minimum_msat: 0,
3368 htlc_maximum_msat: MAX_VALUE_MSAT,
3370 fee_proportional_millionths: 0,
3371 excess_data: Vec::new()
3374 // Check against amount_to_transfer_over_msat.
3375 // Set minimal HTLC of 200_000_000 msat.
3376 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3377 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3378 short_channel_id: 2,
3381 cltv_expiry_delta: 0,
3382 htlc_minimum_msat: 200_000_000,
3383 htlc_maximum_msat: MAX_VALUE_MSAT,
3385 fee_proportional_millionths: 0,
3386 excess_data: Vec::new()
3389 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3391 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3392 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3393 short_channel_id: 4,
3396 cltv_expiry_delta: 0,
3397 htlc_minimum_msat: 0,
3398 htlc_maximum_msat: 199_999_999,
3400 fee_proportional_millionths: 0,
3401 excess_data: Vec::new()
3404 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3405 let route_params = RouteParameters::from_payment_params_and_value(
3406 payment_params, 199_999_999);
3407 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3408 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3409 &Default::default(), &random_seed_bytes) {
3410 assert_eq!(err, "Failed to find a path to the given destination");
3411 } else { panic!(); }
3413 // Lift the restriction on the first hop.
3414 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3415 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3416 short_channel_id: 2,
3419 cltv_expiry_delta: 0,
3420 htlc_minimum_msat: 0,
3421 htlc_maximum_msat: MAX_VALUE_MSAT,
3423 fee_proportional_millionths: 0,
3424 excess_data: Vec::new()
3427 // A payment above the minimum should pass
3428 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3429 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3430 assert_eq!(route.paths[0].hops.len(), 2);
3434 fn htlc_minimum_overpay_test() {
3435 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3436 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3437 let config = UserConfig::default();
3438 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3439 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3441 let scorer = ln_test_utils::TestScorer::new();
3442 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3443 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3445 // A route to node#2 via two paths.
3446 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3447 // Thus, they can't send 60 without overpaying.
3448 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3449 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3450 short_channel_id: 2,
3453 cltv_expiry_delta: 0,
3454 htlc_minimum_msat: 35_000,
3455 htlc_maximum_msat: 40_000,
3457 fee_proportional_millionths: 0,
3458 excess_data: Vec::new()
3460 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3461 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3462 short_channel_id: 12,
3465 cltv_expiry_delta: 0,
3466 htlc_minimum_msat: 35_000,
3467 htlc_maximum_msat: 40_000,
3469 fee_proportional_millionths: 0,
3470 excess_data: Vec::new()
3474 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3475 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3476 short_channel_id: 13,
3479 cltv_expiry_delta: 0,
3480 htlc_minimum_msat: 0,
3481 htlc_maximum_msat: MAX_VALUE_MSAT,
3483 fee_proportional_millionths: 0,
3484 excess_data: Vec::new()
3486 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3487 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3488 short_channel_id: 4,
3491 cltv_expiry_delta: 0,
3492 htlc_minimum_msat: 0,
3493 htlc_maximum_msat: MAX_VALUE_MSAT,
3495 fee_proportional_millionths: 0,
3496 excess_data: Vec::new()
3499 // Disable other paths
3500 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3501 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3502 short_channel_id: 1,
3504 flags: 2, // to disable
3505 cltv_expiry_delta: 0,
3506 htlc_minimum_msat: 0,
3507 htlc_maximum_msat: MAX_VALUE_MSAT,
3509 fee_proportional_millionths: 0,
3510 excess_data: Vec::new()
3513 let mut route_params = RouteParameters::from_payment_params_and_value(
3514 payment_params.clone(), 60_000);
3515 route_params.max_total_routing_fee_msat = Some(15_000);
3516 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3517 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3518 // Overpay fees to hit htlc_minimum_msat.
3519 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3520 // TODO: this could be better balanced to overpay 10k and not 15k.
3521 assert_eq!(overpaid_fees, 15_000);
3523 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3524 // while taking even more fee to match htlc_minimum_msat.
3525 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3526 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3527 short_channel_id: 12,
3530 cltv_expiry_delta: 0,
3531 htlc_minimum_msat: 65_000,
3532 htlc_maximum_msat: 80_000,
3534 fee_proportional_millionths: 0,
3535 excess_data: Vec::new()
3537 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3538 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3539 short_channel_id: 2,
3542 cltv_expiry_delta: 0,
3543 htlc_minimum_msat: 0,
3544 htlc_maximum_msat: MAX_VALUE_MSAT,
3546 fee_proportional_millionths: 0,
3547 excess_data: Vec::new()
3549 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3550 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3551 short_channel_id: 4,
3554 cltv_expiry_delta: 0,
3555 htlc_minimum_msat: 0,
3556 htlc_maximum_msat: MAX_VALUE_MSAT,
3558 fee_proportional_millionths: 100_000,
3559 excess_data: Vec::new()
3562 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3563 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3564 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3565 assert_eq!(route.paths.len(), 1);
3566 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3567 let fees = route.paths[0].hops[0].fee_msat;
3568 assert_eq!(fees, 5_000);
3570 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3571 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3572 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3573 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3574 // the other channel.
3575 assert_eq!(route.paths.len(), 1);
3576 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3577 let fees = route.paths[0].hops[0].fee_msat;
3578 assert_eq!(fees, 5_000);
3582 fn htlc_minimum_recipient_overpay_test() {
3583 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3584 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3585 let config = UserConfig::default();
3586 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3587 let scorer = ln_test_utils::TestScorer::new();
3588 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3589 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3591 // Route to node2 over a single path which requires overpaying the recipient themselves.
3593 // First disable all paths except the us -> node1 -> node2 path
3594 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3595 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3596 short_channel_id: 13,
3599 cltv_expiry_delta: 0,
3600 htlc_minimum_msat: 0,
3601 htlc_maximum_msat: 0,
3603 fee_proportional_millionths: 0,
3604 excess_data: Vec::new()
3607 // Set channel 4 to free but with a high htlc_minimum_msat
3608 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3609 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3610 short_channel_id: 4,
3613 cltv_expiry_delta: 0,
3614 htlc_minimum_msat: 15_000,
3615 htlc_maximum_msat: MAX_VALUE_MSAT,
3617 fee_proportional_millionths: 0,
3618 excess_data: Vec::new()
3621 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3622 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3623 // what we try to find a route for, so this test only just happens to work out to exactly
3625 let mut route_params = RouteParameters::from_payment_params_and_value(
3626 payment_params.clone(), 5_000);
3627 route_params.max_total_routing_fee_msat = Some(9_999);
3628 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3629 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3630 &Default::default(), &random_seed_bytes) {
3631 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3632 } else { panic!(); }
3634 let mut route_params = RouteParameters::from_payment_params_and_value(
3635 payment_params.clone(), 5_000);
3636 route_params.max_total_routing_fee_msat = Some(10_000);
3637 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3638 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3639 assert_eq!(route.get_total_fees(), 10_000);
3643 fn disable_channels_test() {
3644 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3645 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3646 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3647 let scorer = ln_test_utils::TestScorer::new();
3648 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3649 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3651 // // Disable channels 4 and 12 by flags=2
3652 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3653 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3654 short_channel_id: 4,
3656 flags: 2, // to disable
3657 cltv_expiry_delta: 0,
3658 htlc_minimum_msat: 0,
3659 htlc_maximum_msat: MAX_VALUE_MSAT,
3661 fee_proportional_millionths: 0,
3662 excess_data: Vec::new()
3664 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3665 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3666 short_channel_id: 12,
3668 flags: 2, // to disable
3669 cltv_expiry_delta: 0,
3670 htlc_minimum_msat: 0,
3671 htlc_maximum_msat: MAX_VALUE_MSAT,
3673 fee_proportional_millionths: 0,
3674 excess_data: Vec::new()
3677 // If all the channels require some features we don't understand, route should fail
3678 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3679 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3680 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3681 &Default::default(), &random_seed_bytes) {
3682 assert_eq!(err, "Failed to find a path to the given destination");
3683 } else { panic!(); }
3685 // If we specify a channel to node7, that overrides our local channel view and that gets used
3686 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3687 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3688 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3689 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3690 &Default::default(), &random_seed_bytes).unwrap();
3691 assert_eq!(route.paths[0].hops.len(), 2);
3693 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3694 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3695 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3696 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3697 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3698 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3700 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3701 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3702 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3703 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3704 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3705 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3709 fn disable_node_test() {
3710 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3711 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3712 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3713 let scorer = ln_test_utils::TestScorer::new();
3714 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3715 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3717 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3718 let mut unknown_features = NodeFeatures::empty();
3719 unknown_features.set_unknown_feature_required();
3720 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3721 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3722 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3724 // If all nodes require some features we don't understand, route should fail
3725 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3726 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3727 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3728 &Default::default(), &random_seed_bytes) {
3729 assert_eq!(err, "Failed to find a path to the given destination");
3730 } else { panic!(); }
3732 // If we specify a channel to node7, that overrides our local channel view and that gets used
3733 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3734 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3735 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3736 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3737 &Default::default(), &random_seed_bytes).unwrap();
3738 assert_eq!(route.paths[0].hops.len(), 2);
3740 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3741 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3742 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3743 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3744 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3745 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3747 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3748 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3749 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3750 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3751 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3752 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3754 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3755 // naively) assume that the user checked the feature bits on the invoice, which override
3756 // the node_announcement.
3760 fn our_chans_test() {
3761 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3762 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3763 let scorer = ln_test_utils::TestScorer::new();
3764 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3765 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3767 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3768 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3769 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3770 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3771 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3772 assert_eq!(route.paths[0].hops.len(), 3);
3774 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3775 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3776 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3777 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3778 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3779 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3781 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3782 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3783 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3784 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3785 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3786 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3788 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3789 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3790 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3791 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3792 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3793 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3795 // If we specify a channel to node7, that overrides our local channel view and that gets used
3796 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3797 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3798 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3799 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3800 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3801 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3802 &Default::default(), &random_seed_bytes).unwrap();
3803 assert_eq!(route.paths[0].hops.len(), 2);
3805 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3806 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3807 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3808 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3809 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3810 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3812 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3813 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3814 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3815 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3816 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3817 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3820 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3821 let zero_fees = RoutingFees {
3823 proportional_millionths: 0,
3825 vec![RouteHint(vec![RouteHintHop {
3826 src_node_id: nodes[3],
3827 short_channel_id: 8,
3829 cltv_expiry_delta: (8 << 4) | 1,
3830 htlc_minimum_msat: None,
3831 htlc_maximum_msat: None,
3833 ]), RouteHint(vec![RouteHintHop {
3834 src_node_id: nodes[4],
3835 short_channel_id: 9,
3838 proportional_millionths: 0,
3840 cltv_expiry_delta: (9 << 4) | 1,
3841 htlc_minimum_msat: None,
3842 htlc_maximum_msat: None,
3843 }]), RouteHint(vec![RouteHintHop {
3844 src_node_id: nodes[5],
3845 short_channel_id: 10,
3847 cltv_expiry_delta: (10 << 4) | 1,
3848 htlc_minimum_msat: None,
3849 htlc_maximum_msat: None,
3853 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3854 let zero_fees = RoutingFees {
3856 proportional_millionths: 0,
3858 vec![RouteHint(vec![RouteHintHop {
3859 src_node_id: nodes[2],
3860 short_channel_id: 5,
3863 proportional_millionths: 0,
3865 cltv_expiry_delta: (5 << 4) | 1,
3866 htlc_minimum_msat: None,
3867 htlc_maximum_msat: None,
3869 src_node_id: nodes[3],
3870 short_channel_id: 8,
3872 cltv_expiry_delta: (8 << 4) | 1,
3873 htlc_minimum_msat: None,
3874 htlc_maximum_msat: None,
3876 ]), RouteHint(vec![RouteHintHop {
3877 src_node_id: nodes[4],
3878 short_channel_id: 9,
3881 proportional_millionths: 0,
3883 cltv_expiry_delta: (9 << 4) | 1,
3884 htlc_minimum_msat: None,
3885 htlc_maximum_msat: None,
3886 }]), RouteHint(vec![RouteHintHop {
3887 src_node_id: nodes[5],
3888 short_channel_id: 10,
3890 cltv_expiry_delta: (10 << 4) | 1,
3891 htlc_minimum_msat: None,
3892 htlc_maximum_msat: None,
3897 fn partial_route_hint_test() {
3898 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3899 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3900 let scorer = ln_test_utils::TestScorer::new();
3901 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3902 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3904 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3905 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3906 // RouteHint may be partially used by the algo to build the best path.
3908 // First check that last hop can't have its source as the payee.
3909 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3910 src_node_id: nodes[6],
3911 short_channel_id: 8,
3914 proportional_millionths: 0,
3916 cltv_expiry_delta: (8 << 4) | 1,
3917 htlc_minimum_msat: None,
3918 htlc_maximum_msat: None,
3921 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3922 invalid_last_hops.push(invalid_last_hop);
3924 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3925 .with_route_hints(invalid_last_hops).unwrap();
3926 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3927 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3928 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3929 &Default::default(), &random_seed_bytes) {
3930 assert_eq!(err, "Route hint cannot have the payee as the source.");
3931 } else { panic!(); }
3934 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3935 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3936 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3937 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3938 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3939 assert_eq!(route.paths[0].hops.len(), 5);
3941 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3942 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3943 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3944 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3945 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3946 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3948 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3949 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3950 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3951 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3952 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3953 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3955 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3956 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3957 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3958 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3959 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3960 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3962 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3963 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3964 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3965 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3966 // If we have a peer in the node map, we'll use their features here since we don't have
3967 // a way of figuring out their features from the invoice:
3968 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3969 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3971 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3972 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3973 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3974 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3975 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3976 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3979 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3980 let zero_fees = RoutingFees {
3982 proportional_millionths: 0,
3984 vec![RouteHint(vec![RouteHintHop {
3985 src_node_id: nodes[3],
3986 short_channel_id: 8,
3988 cltv_expiry_delta: (8 << 4) | 1,
3989 htlc_minimum_msat: None,
3990 htlc_maximum_msat: None,
3991 }]), RouteHint(vec![
3993 ]), RouteHint(vec![RouteHintHop {
3994 src_node_id: nodes[5],
3995 short_channel_id: 10,
3997 cltv_expiry_delta: (10 << 4) | 1,
3998 htlc_minimum_msat: None,
3999 htlc_maximum_msat: None,
4004 fn ignores_empty_last_hops_test() {
4005 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4006 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4007 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
4008 let scorer = ln_test_utils::TestScorer::new();
4009 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4010 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4012 // Test handling of an empty RouteHint passed in Invoice.
4013 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4014 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4015 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4016 assert_eq!(route.paths[0].hops.len(), 5);
4018 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4019 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4020 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4021 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4022 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4023 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4025 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4026 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4027 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4028 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4029 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4030 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4032 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4033 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4034 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4035 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4036 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4037 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4039 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4040 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4041 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4042 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4043 // If we have a peer in the node map, we'll use their features here since we don't have
4044 // a way of figuring out their features from the invoice:
4045 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4046 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4048 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4049 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4050 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4051 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4052 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4053 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4056 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
4058 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
4059 let zero_fees = RoutingFees {
4061 proportional_millionths: 0,
4063 vec![RouteHint(vec![RouteHintHop {
4064 src_node_id: hint_hops[0],
4065 short_channel_id: 0xff00,
4068 proportional_millionths: 0,
4070 cltv_expiry_delta: (5 << 4) | 1,
4071 htlc_minimum_msat: None,
4072 htlc_maximum_msat: None,
4074 src_node_id: hint_hops[1],
4075 short_channel_id: 0xff01,
4077 cltv_expiry_delta: (8 << 4) | 1,
4078 htlc_minimum_msat: None,
4079 htlc_maximum_msat: None,
4084 fn multi_hint_last_hops_test() {
4085 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4086 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4087 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
4088 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4089 let scorer = ln_test_utils::TestScorer::new();
4090 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4091 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4092 // Test through channels 2, 3, 0xff00, 0xff01.
4093 // Test shows that multiple hop hints are considered.
4095 // Disabling channels 6 & 7 by flags=2
4096 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4097 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4098 short_channel_id: 6,
4100 flags: 2, // to disable
4101 cltv_expiry_delta: 0,
4102 htlc_minimum_msat: 0,
4103 htlc_maximum_msat: MAX_VALUE_MSAT,
4105 fee_proportional_millionths: 0,
4106 excess_data: Vec::new()
4108 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4109 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4110 short_channel_id: 7,
4112 flags: 2, // to disable
4113 cltv_expiry_delta: 0,
4114 htlc_minimum_msat: 0,
4115 htlc_maximum_msat: MAX_VALUE_MSAT,
4117 fee_proportional_millionths: 0,
4118 excess_data: Vec::new()
4121 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4122 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4123 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4124 assert_eq!(route.paths[0].hops.len(), 4);
4126 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4127 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4128 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4129 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4130 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4131 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4133 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4134 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4135 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4136 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4137 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4138 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4140 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
4141 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4142 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4143 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4144 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
4145 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4147 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4148 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4149 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4150 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4151 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4152 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4156 fn private_multi_hint_last_hops_test() {
4157 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4158 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4160 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
4161 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
4163 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
4164 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4165 let scorer = ln_test_utils::TestScorer::new();
4166 // Test through channels 2, 3, 0xff00, 0xff01.
4167 // Test shows that multiple hop hints are considered.
4169 // Disabling channels 6 & 7 by flags=2
4170 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4171 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4172 short_channel_id: 6,
4174 flags: 2, // to disable
4175 cltv_expiry_delta: 0,
4176 htlc_minimum_msat: 0,
4177 htlc_maximum_msat: MAX_VALUE_MSAT,
4179 fee_proportional_millionths: 0,
4180 excess_data: Vec::new()
4182 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4183 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4184 short_channel_id: 7,
4186 flags: 2, // to disable
4187 cltv_expiry_delta: 0,
4188 htlc_minimum_msat: 0,
4189 htlc_maximum_msat: MAX_VALUE_MSAT,
4191 fee_proportional_millionths: 0,
4192 excess_data: Vec::new()
4195 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4196 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4197 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4198 assert_eq!(route.paths[0].hops.len(), 4);
4200 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4201 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4202 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4203 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4204 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4205 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4207 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4208 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4209 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4210 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4211 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4212 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4214 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4215 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4216 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4217 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4218 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4219 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4221 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4222 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4223 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4224 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4225 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4226 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4229 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4230 let zero_fees = RoutingFees {
4232 proportional_millionths: 0,
4234 vec![RouteHint(vec![RouteHintHop {
4235 src_node_id: nodes[4],
4236 short_channel_id: 11,
4238 cltv_expiry_delta: (11 << 4) | 1,
4239 htlc_minimum_msat: None,
4240 htlc_maximum_msat: None,
4242 src_node_id: nodes[3],
4243 short_channel_id: 8,
4245 cltv_expiry_delta: (8 << 4) | 1,
4246 htlc_minimum_msat: None,
4247 htlc_maximum_msat: None,
4248 }]), RouteHint(vec![RouteHintHop {
4249 src_node_id: nodes[4],
4250 short_channel_id: 9,
4253 proportional_millionths: 0,
4255 cltv_expiry_delta: (9 << 4) | 1,
4256 htlc_minimum_msat: None,
4257 htlc_maximum_msat: None,
4258 }]), RouteHint(vec![RouteHintHop {
4259 src_node_id: nodes[5],
4260 short_channel_id: 10,
4262 cltv_expiry_delta: (10 << 4) | 1,
4263 htlc_minimum_msat: None,
4264 htlc_maximum_msat: None,
4269 fn last_hops_with_public_channel_test() {
4270 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4271 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4272 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4273 let scorer = ln_test_utils::TestScorer::new();
4274 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4275 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4276 // This test shows that public routes can be present in the invoice
4277 // which would be handled in the same manner.
4279 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4280 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4281 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4282 assert_eq!(route.paths[0].hops.len(), 5);
4284 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4285 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4286 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4287 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4288 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4289 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4291 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4292 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4293 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4294 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4295 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4296 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4298 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4299 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4300 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4301 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4302 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4303 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4305 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4306 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4307 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4308 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4309 // If we have a peer in the node map, we'll use their features here since we don't have
4310 // a way of figuring out their features from the invoice:
4311 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4312 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4314 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4315 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4316 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4317 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4318 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4319 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4323 fn our_chans_last_hop_connect_test() {
4324 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4325 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4326 let scorer = ln_test_utils::TestScorer::new();
4327 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4328 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4330 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4331 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4332 let mut last_hops = last_hops(&nodes);
4333 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4334 .with_route_hints(last_hops.clone()).unwrap();
4335 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4336 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4337 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4338 &Default::default(), &random_seed_bytes).unwrap();
4339 assert_eq!(route.paths[0].hops.len(), 2);
4341 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4342 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4343 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4344 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4345 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4346 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4348 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4349 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4350 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4351 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4352 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4353 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4355 last_hops[0].0[0].fees.base_msat = 1000;
4357 // Revert to via 6 as the fee on 8 goes up
4358 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4359 .with_route_hints(last_hops).unwrap();
4360 let route_params = RouteParameters::from_payment_params_and_value(
4361 payment_params.clone(), 100);
4362 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4363 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4364 assert_eq!(route.paths[0].hops.len(), 4);
4366 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4367 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4368 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4369 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4370 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4371 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4373 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4374 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4375 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4376 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4377 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4378 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4380 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4381 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4382 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4383 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4384 // If we have a peer in the node map, we'll use their features here since we don't have
4385 // a way of figuring out their features from the invoice:
4386 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4387 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4389 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4390 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4391 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4392 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4393 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4394 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4396 // ...but still use 8 for larger payments as 6 has a variable feerate
4397 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4398 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4399 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4400 assert_eq!(route.paths[0].hops.len(), 5);
4402 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4403 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4404 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4405 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4406 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4407 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4409 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4410 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4411 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4412 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4413 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4414 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4416 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4417 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4418 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4419 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4420 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4421 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4423 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4424 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4425 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4426 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4427 // If we have a peer in the node map, we'll use their features here since we don't have
4428 // a way of figuring out their features from the invoice:
4429 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4430 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4432 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4433 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4434 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4435 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4436 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4437 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4440 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> {
4441 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4442 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4443 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4445 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4446 let last_hops = RouteHint(vec![RouteHintHop {
4447 src_node_id: middle_node_id,
4448 short_channel_id: 8,
4451 proportional_millionths: last_hop_fee_prop,
4453 cltv_expiry_delta: (8 << 4) | 1,
4454 htlc_minimum_msat: None,
4455 htlc_maximum_msat: last_hop_htlc_max,
4457 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4458 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4459 let scorer = ln_test_utils::TestScorer::new();
4460 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4461 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4462 let logger = ln_test_utils::TestLogger::new();
4463 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4464 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4465 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4466 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4467 &random_seed_bytes);
4472 fn unannounced_path_test() {
4473 // We should be able to send a payment to a destination without any help of a routing graph
4474 // if we have a channel with a common counterparty that appears in the first and last hop
4476 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4478 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4479 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4480 assert_eq!(route.paths[0].hops.len(), 2);
4482 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4483 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4484 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4485 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4486 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4487 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4489 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4490 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4491 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4492 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4493 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4494 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4498 fn overflow_unannounced_path_test_liquidity_underflow() {
4499 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4500 // the last-hop had a fee which overflowed a u64, we'd panic.
4501 // This was due to us adding the first-hop from us unconditionally, causing us to think
4502 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4503 // In this test, we previously hit a subtraction underflow due to having less available
4504 // liquidity at the last hop than 0.
4505 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());
4509 fn overflow_unannounced_path_test_feerate_overflow() {
4510 // This tests for the same case as above, except instead of hitting a subtraction
4511 // underflow, we hit a case where the fee charged at a hop overflowed.
4512 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());
4516 fn available_amount_while_routing_test() {
4517 // Tests whether we choose the correct available channel amount while routing.
4519 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4520 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4521 let scorer = ln_test_utils::TestScorer::new();
4522 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4523 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4524 let config = UserConfig::default();
4525 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4526 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4529 // We will use a simple single-path route from
4530 // our node to node2 via node0: channels {1, 3}.
4532 // First disable all other paths.
4533 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4534 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4535 short_channel_id: 2,
4538 cltv_expiry_delta: 0,
4539 htlc_minimum_msat: 0,
4540 htlc_maximum_msat: 100_000,
4542 fee_proportional_millionths: 0,
4543 excess_data: Vec::new()
4545 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4546 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4547 short_channel_id: 12,
4550 cltv_expiry_delta: 0,
4551 htlc_minimum_msat: 0,
4552 htlc_maximum_msat: 100_000,
4554 fee_proportional_millionths: 0,
4555 excess_data: Vec::new()
4558 // Make the first channel (#1) very permissive,
4559 // and we will be testing all limits on the second channel.
4560 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4561 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4562 short_channel_id: 1,
4565 cltv_expiry_delta: 0,
4566 htlc_minimum_msat: 0,
4567 htlc_maximum_msat: 1_000_000_000,
4569 fee_proportional_millionths: 0,
4570 excess_data: Vec::new()
4573 // First, let's see if routing works if we have absolutely no idea about the available amount.
4574 // In this case, it should be set to 250_000 sats.
4575 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4576 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4577 short_channel_id: 3,
4580 cltv_expiry_delta: 0,
4581 htlc_minimum_msat: 0,
4582 htlc_maximum_msat: 250_000_000,
4584 fee_proportional_millionths: 0,
4585 excess_data: Vec::new()
4589 // Attempt to route more than available results in a failure.
4590 let route_params = RouteParameters::from_payment_params_and_value(
4591 payment_params.clone(), 250_000_001);
4592 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4593 &our_id, &route_params, &network_graph.read_only(), None,
4594 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4595 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4596 } else { panic!(); }
4600 // Now, attempt to route an exact amount we have should be fine.
4601 let route_params = RouteParameters::from_payment_params_and_value(
4602 payment_params.clone(), 250_000_000);
4603 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4604 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4605 assert_eq!(route.paths.len(), 1);
4606 let path = route.paths.last().unwrap();
4607 assert_eq!(path.hops.len(), 2);
4608 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4609 assert_eq!(path.final_value_msat(), 250_000_000);
4612 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4613 // Disable channel #1 and use another first hop.
4614 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4615 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4616 short_channel_id: 1,
4619 cltv_expiry_delta: 0,
4620 htlc_minimum_msat: 0,
4621 htlc_maximum_msat: 1_000_000_000,
4623 fee_proportional_millionths: 0,
4624 excess_data: Vec::new()
4627 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4628 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4631 // Attempt to route more than available results in a failure.
4632 let route_params = RouteParameters::from_payment_params_and_value(
4633 payment_params.clone(), 200_000_001);
4634 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4635 &our_id, &route_params, &network_graph.read_only(),
4636 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4637 &Default::default(), &random_seed_bytes) {
4638 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4639 } else { panic!(); }
4643 // Now, attempt to route an exact amount we have should be fine.
4644 let route_params = RouteParameters::from_payment_params_and_value(
4645 payment_params.clone(), 200_000_000);
4646 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4647 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4648 &Default::default(), &random_seed_bytes).unwrap();
4649 assert_eq!(route.paths.len(), 1);
4650 let path = route.paths.last().unwrap();
4651 assert_eq!(path.hops.len(), 2);
4652 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4653 assert_eq!(path.final_value_msat(), 200_000_000);
4656 // Enable channel #1 back.
4657 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4658 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4659 short_channel_id: 1,
4662 cltv_expiry_delta: 0,
4663 htlc_minimum_msat: 0,
4664 htlc_maximum_msat: 1_000_000_000,
4666 fee_proportional_millionths: 0,
4667 excess_data: Vec::new()
4671 // Now let's see if routing works if we know only htlc_maximum_msat.
4672 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4673 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4674 short_channel_id: 3,
4677 cltv_expiry_delta: 0,
4678 htlc_minimum_msat: 0,
4679 htlc_maximum_msat: 15_000,
4681 fee_proportional_millionths: 0,
4682 excess_data: Vec::new()
4686 // Attempt to route more than available results in a failure.
4687 let route_params = RouteParameters::from_payment_params_and_value(
4688 payment_params.clone(), 15_001);
4689 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4690 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4691 &scorer, &Default::default(), &random_seed_bytes) {
4692 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4693 } else { panic!(); }
4697 // Now, attempt to route an exact amount we have should be fine.
4698 let route_params = RouteParameters::from_payment_params_and_value(
4699 payment_params.clone(), 15_000);
4700 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4701 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4702 assert_eq!(route.paths.len(), 1);
4703 let path = route.paths.last().unwrap();
4704 assert_eq!(path.hops.len(), 2);
4705 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4706 assert_eq!(path.final_value_msat(), 15_000);
4709 // Now let's see if routing works if we know only capacity from the UTXO.
4711 // We can't change UTXO capacity on the fly, so we'll disable
4712 // the existing channel and add another one with the capacity we need.
4713 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4714 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4715 short_channel_id: 3,
4718 cltv_expiry_delta: 0,
4719 htlc_minimum_msat: 0,
4720 htlc_maximum_msat: MAX_VALUE_MSAT,
4722 fee_proportional_millionths: 0,
4723 excess_data: Vec::new()
4726 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4727 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4728 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4729 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4730 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4732 *chain_monitor.utxo_ret.lock().unwrap() =
4733 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4734 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4736 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4737 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4738 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4739 short_channel_id: 333,
4742 cltv_expiry_delta: (3 << 4) | 1,
4743 htlc_minimum_msat: 0,
4744 htlc_maximum_msat: 15_000,
4746 fee_proportional_millionths: 0,
4747 excess_data: Vec::new()
4749 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4750 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4751 short_channel_id: 333,
4754 cltv_expiry_delta: (3 << 4) | 2,
4755 htlc_minimum_msat: 0,
4756 htlc_maximum_msat: 15_000,
4758 fee_proportional_millionths: 0,
4759 excess_data: Vec::new()
4763 // Attempt to route more than available results in a failure.
4764 let route_params = RouteParameters::from_payment_params_and_value(
4765 payment_params.clone(), 15_001);
4766 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4767 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4768 &scorer, &Default::default(), &random_seed_bytes) {
4769 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4770 } else { panic!(); }
4774 // Now, attempt to route an exact amount we have should be fine.
4775 let route_params = RouteParameters::from_payment_params_and_value(
4776 payment_params.clone(), 15_000);
4777 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4778 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4779 assert_eq!(route.paths.len(), 1);
4780 let path = route.paths.last().unwrap();
4781 assert_eq!(path.hops.len(), 2);
4782 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4783 assert_eq!(path.final_value_msat(), 15_000);
4786 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4787 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4788 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4789 short_channel_id: 333,
4792 cltv_expiry_delta: 0,
4793 htlc_minimum_msat: 0,
4794 htlc_maximum_msat: 10_000,
4796 fee_proportional_millionths: 0,
4797 excess_data: Vec::new()
4801 // Attempt to route more than available results in a failure.
4802 let route_params = RouteParameters::from_payment_params_and_value(
4803 payment_params.clone(), 10_001);
4804 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4805 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4806 &scorer, &Default::default(), &random_seed_bytes) {
4807 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4808 } else { panic!(); }
4812 // Now, attempt to route an exact amount we have should be fine.
4813 let route_params = RouteParameters::from_payment_params_and_value(
4814 payment_params.clone(), 10_000);
4815 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4816 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4817 assert_eq!(route.paths.len(), 1);
4818 let path = route.paths.last().unwrap();
4819 assert_eq!(path.hops.len(), 2);
4820 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4821 assert_eq!(path.final_value_msat(), 10_000);
4826 fn available_liquidity_last_hop_test() {
4827 // Check that available liquidity properly limits the path even when only
4828 // one of the latter hops is limited.
4829 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4830 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4831 let scorer = ln_test_utils::TestScorer::new();
4832 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4833 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4834 let config = UserConfig::default();
4835 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4836 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4839 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4840 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4841 // Total capacity: 50 sats.
4843 // Disable other potential paths.
4844 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4845 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4846 short_channel_id: 2,
4849 cltv_expiry_delta: 0,
4850 htlc_minimum_msat: 0,
4851 htlc_maximum_msat: 100_000,
4853 fee_proportional_millionths: 0,
4854 excess_data: Vec::new()
4856 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4857 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4858 short_channel_id: 7,
4861 cltv_expiry_delta: 0,
4862 htlc_minimum_msat: 0,
4863 htlc_maximum_msat: 100_000,
4865 fee_proportional_millionths: 0,
4866 excess_data: Vec::new()
4871 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4872 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4873 short_channel_id: 12,
4876 cltv_expiry_delta: 0,
4877 htlc_minimum_msat: 0,
4878 htlc_maximum_msat: 100_000,
4880 fee_proportional_millionths: 0,
4881 excess_data: Vec::new()
4883 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4884 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4885 short_channel_id: 13,
4888 cltv_expiry_delta: 0,
4889 htlc_minimum_msat: 0,
4890 htlc_maximum_msat: 100_000,
4892 fee_proportional_millionths: 0,
4893 excess_data: Vec::new()
4896 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4897 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4898 short_channel_id: 6,
4901 cltv_expiry_delta: 0,
4902 htlc_minimum_msat: 0,
4903 htlc_maximum_msat: 50_000,
4905 fee_proportional_millionths: 0,
4906 excess_data: Vec::new()
4908 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4909 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4910 short_channel_id: 11,
4913 cltv_expiry_delta: 0,
4914 htlc_minimum_msat: 0,
4915 htlc_maximum_msat: 100_000,
4917 fee_proportional_millionths: 0,
4918 excess_data: Vec::new()
4921 // Attempt to route more than available results in a failure.
4922 let route_params = RouteParameters::from_payment_params_and_value(
4923 payment_params.clone(), 60_000);
4924 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4925 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4926 &scorer, &Default::default(), &random_seed_bytes) {
4927 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4928 } else { panic!(); }
4932 // Now, attempt to route 49 sats (just a bit below the capacity).
4933 let route_params = RouteParameters::from_payment_params_and_value(
4934 payment_params.clone(), 49_000);
4935 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4936 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4937 assert_eq!(route.paths.len(), 1);
4938 let mut total_amount_paid_msat = 0;
4939 for path in &route.paths {
4940 assert_eq!(path.hops.len(), 4);
4941 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4942 total_amount_paid_msat += path.final_value_msat();
4944 assert_eq!(total_amount_paid_msat, 49_000);
4948 // Attempt to route an exact amount is also fine
4949 let route_params = RouteParameters::from_payment_params_and_value(
4950 payment_params, 50_000);
4951 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4952 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4953 assert_eq!(route.paths.len(), 1);
4954 let mut total_amount_paid_msat = 0;
4955 for path in &route.paths {
4956 assert_eq!(path.hops.len(), 4);
4957 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4958 total_amount_paid_msat += path.final_value_msat();
4960 assert_eq!(total_amount_paid_msat, 50_000);
4965 fn ignore_fee_first_hop_test() {
4966 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4967 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4968 let scorer = ln_test_utils::TestScorer::new();
4969 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4970 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4971 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4973 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4974 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4975 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4976 short_channel_id: 1,
4979 cltv_expiry_delta: 0,
4980 htlc_minimum_msat: 0,
4981 htlc_maximum_msat: 100_000,
4982 fee_base_msat: 1_000_000,
4983 fee_proportional_millionths: 0,
4984 excess_data: Vec::new()
4986 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4987 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4988 short_channel_id: 3,
4991 cltv_expiry_delta: 0,
4992 htlc_minimum_msat: 0,
4993 htlc_maximum_msat: 50_000,
4995 fee_proportional_millionths: 0,
4996 excess_data: Vec::new()
5000 let route_params = RouteParameters::from_payment_params_and_value(
5001 payment_params, 50_000);
5002 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5003 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5004 assert_eq!(route.paths.len(), 1);
5005 let mut total_amount_paid_msat = 0;
5006 for path in &route.paths {
5007 assert_eq!(path.hops.len(), 2);
5008 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5009 total_amount_paid_msat += path.final_value_msat();
5011 assert_eq!(total_amount_paid_msat, 50_000);
5016 fn simple_mpp_route_test() {
5017 let (secp_ctx, _, _, _, _) = build_graph();
5018 let (_, _, _, nodes) = get_nodes(&secp_ctx);
5019 let config = UserConfig::default();
5020 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5021 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5023 do_simple_mpp_route_test(clear_payment_params);
5025 // MPP to a 1-hop blinded path for nodes[2]
5026 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
5027 let blinded_path = BlindedPath {
5028 introduction_node_id: nodes[2],
5029 blinding_point: ln_test_utils::pubkey(42),
5030 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
5032 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
5034 fee_proportional_millionths: 0,
5035 htlc_minimum_msat: 0,
5036 htlc_maximum_msat: 0,
5037 cltv_expiry_delta: 0,
5038 features: BlindedHopFeatures::empty(),
5040 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
5041 .with_bolt12_features(bolt12_features.clone()).unwrap();
5042 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
5044 // MPP to 3 2-hop blinded paths
5045 let mut blinded_path_node_0 = blinded_path.clone();
5046 blinded_path_node_0.introduction_node_id = nodes[0];
5047 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
5048 let mut node_0_payinfo = blinded_payinfo.clone();
5049 node_0_payinfo.htlc_maximum_msat = 50_000;
5051 let mut blinded_path_node_7 = blinded_path_node_0.clone();
5052 blinded_path_node_7.introduction_node_id = nodes[7];
5053 let mut node_7_payinfo = blinded_payinfo.clone();
5054 node_7_payinfo.htlc_maximum_msat = 60_000;
5056 let mut blinded_path_node_1 = blinded_path_node_0.clone();
5057 blinded_path_node_1.introduction_node_id = nodes[1];
5058 let mut node_1_payinfo = blinded_payinfo.clone();
5059 node_1_payinfo.htlc_maximum_msat = 180_000;
5061 let two_hop_blinded_payment_params = PaymentParameters::blinded(
5063 (node_0_payinfo, blinded_path_node_0),
5064 (node_7_payinfo, blinded_path_node_7),
5065 (node_1_payinfo, blinded_path_node_1)
5067 .with_bolt12_features(bolt12_features).unwrap();
5068 do_simple_mpp_route_test(two_hop_blinded_payment_params);
5072 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
5073 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5074 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5075 let scorer = ln_test_utils::TestScorer::new();
5076 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5077 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5079 // We need a route consisting of 3 paths:
5080 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5081 // To achieve this, the amount being transferred should be around
5082 // the total capacity of these 3 paths.
5084 // First, we set limits on these (previously unlimited) channels.
5085 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
5087 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5088 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5089 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5090 short_channel_id: 1,
5093 cltv_expiry_delta: 0,
5094 htlc_minimum_msat: 0,
5095 htlc_maximum_msat: 100_000,
5097 fee_proportional_millionths: 0,
5098 excess_data: Vec::new()
5100 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5101 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5102 short_channel_id: 3,
5105 cltv_expiry_delta: 0,
5106 htlc_minimum_msat: 0,
5107 htlc_maximum_msat: 50_000,
5109 fee_proportional_millionths: 0,
5110 excess_data: Vec::new()
5113 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
5114 // (total limit 60).
5115 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5116 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5117 short_channel_id: 12,
5120 cltv_expiry_delta: 0,
5121 htlc_minimum_msat: 0,
5122 htlc_maximum_msat: 60_000,
5124 fee_proportional_millionths: 0,
5125 excess_data: Vec::new()
5127 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5128 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5129 short_channel_id: 13,
5132 cltv_expiry_delta: 0,
5133 htlc_minimum_msat: 0,
5134 htlc_maximum_msat: 60_000,
5136 fee_proportional_millionths: 0,
5137 excess_data: Vec::new()
5140 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
5141 // (total capacity 180 sats).
5142 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5143 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5144 short_channel_id: 2,
5147 cltv_expiry_delta: 0,
5148 htlc_minimum_msat: 0,
5149 htlc_maximum_msat: 200_000,
5151 fee_proportional_millionths: 0,
5152 excess_data: Vec::new()
5154 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5155 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5156 short_channel_id: 4,
5159 cltv_expiry_delta: 0,
5160 htlc_minimum_msat: 0,
5161 htlc_maximum_msat: 180_000,
5163 fee_proportional_millionths: 0,
5164 excess_data: Vec::new()
5168 // Attempt to route more than available results in a failure.
5169 let route_params = RouteParameters::from_payment_params_and_value(
5170 payment_params.clone(), 300_000);
5171 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5172 &our_id, &route_params, &network_graph.read_only(), None,
5173 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5174 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5175 } else { panic!(); }
5179 // Attempt to route while setting max_path_count to 0 results in a failure.
5180 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5181 let route_params = RouteParameters::from_payment_params_and_value(
5182 zero_payment_params, 100);
5183 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5184 &our_id, &route_params, &network_graph.read_only(), None,
5185 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5186 assert_eq!(err, "Can't find a route with no paths allowed.");
5187 } else { panic!(); }
5191 // Attempt to route while setting max_path_count to 3 results in a failure.
5192 // This is the case because the minimal_value_contribution_msat would require each path
5193 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5194 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5195 let route_params = RouteParameters::from_payment_params_and_value(
5196 fail_payment_params, 250_000);
5197 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5198 &our_id, &route_params, &network_graph.read_only(), None,
5199 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5200 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5201 } else { panic!(); }
5205 // Now, attempt to route 250 sats (just a bit below the capacity).
5206 // Our algorithm should provide us with these 3 paths.
5207 let route_params = RouteParameters::from_payment_params_and_value(
5208 payment_params.clone(), 250_000);
5209 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5210 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5211 assert_eq!(route.paths.len(), 3);
5212 let mut total_amount_paid_msat = 0;
5213 for path in &route.paths {
5214 if let Some(bt) = &path.blinded_tail {
5215 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5217 assert_eq!(path.hops.len(), 2);
5218 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5220 total_amount_paid_msat += path.final_value_msat();
5222 assert_eq!(total_amount_paid_msat, 250_000);
5226 // Attempt to route an exact amount is also fine
5227 let route_params = RouteParameters::from_payment_params_and_value(
5228 payment_params.clone(), 290_000);
5229 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5230 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5231 assert_eq!(route.paths.len(), 3);
5232 let mut total_amount_paid_msat = 0;
5233 for path in &route.paths {
5234 if payment_params.payee.blinded_route_hints().len() != 0 {
5235 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5236 if let Some(bt) = &path.blinded_tail {
5237 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5238 if bt.hops.len() > 1 {
5239 assert_eq!(path.hops.last().unwrap().pubkey,
5240 payment_params.payee.blinded_route_hints().iter()
5241 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5242 .map(|(_, p)| p.introduction_node_id).unwrap());
5244 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5247 assert_eq!(path.hops.len(), 2);
5248 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5250 total_amount_paid_msat += path.final_value_msat();
5252 assert_eq!(total_amount_paid_msat, 290_000);
5257 fn long_mpp_route_test() {
5258 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5259 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5260 let scorer = ln_test_utils::TestScorer::new();
5261 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5262 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5263 let config = UserConfig::default();
5264 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5265 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5268 // We need a route consisting of 3 paths:
5269 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5270 // Note that these paths overlap (channels 5, 12, 13).
5271 // We will route 300 sats.
5272 // Each path will have 100 sats capacity, those channels which
5273 // are used twice will have 200 sats capacity.
5275 // Disable other potential paths.
5276 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5277 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5278 short_channel_id: 2,
5281 cltv_expiry_delta: 0,
5282 htlc_minimum_msat: 0,
5283 htlc_maximum_msat: 100_000,
5285 fee_proportional_millionths: 0,
5286 excess_data: Vec::new()
5288 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5289 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5290 short_channel_id: 7,
5293 cltv_expiry_delta: 0,
5294 htlc_minimum_msat: 0,
5295 htlc_maximum_msat: 100_000,
5297 fee_proportional_millionths: 0,
5298 excess_data: Vec::new()
5301 // Path via {node0, node2} is channels {1, 3, 5}.
5302 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5303 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5304 short_channel_id: 1,
5307 cltv_expiry_delta: 0,
5308 htlc_minimum_msat: 0,
5309 htlc_maximum_msat: 100_000,
5311 fee_proportional_millionths: 0,
5312 excess_data: Vec::new()
5314 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5315 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5316 short_channel_id: 3,
5319 cltv_expiry_delta: 0,
5320 htlc_minimum_msat: 0,
5321 htlc_maximum_msat: 100_000,
5323 fee_proportional_millionths: 0,
5324 excess_data: Vec::new()
5327 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5328 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5329 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5330 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5331 short_channel_id: 5,
5334 cltv_expiry_delta: 0,
5335 htlc_minimum_msat: 0,
5336 htlc_maximum_msat: 200_000,
5338 fee_proportional_millionths: 0,
5339 excess_data: Vec::new()
5342 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5343 // Add 100 sats to the capacities of {12, 13}, because these channels
5344 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5345 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5346 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5347 short_channel_id: 12,
5350 cltv_expiry_delta: 0,
5351 htlc_minimum_msat: 0,
5352 htlc_maximum_msat: 200_000,
5354 fee_proportional_millionths: 0,
5355 excess_data: Vec::new()
5357 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5358 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5359 short_channel_id: 13,
5362 cltv_expiry_delta: 0,
5363 htlc_minimum_msat: 0,
5364 htlc_maximum_msat: 200_000,
5366 fee_proportional_millionths: 0,
5367 excess_data: Vec::new()
5370 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5371 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5372 short_channel_id: 6,
5375 cltv_expiry_delta: 0,
5376 htlc_minimum_msat: 0,
5377 htlc_maximum_msat: 100_000,
5379 fee_proportional_millionths: 0,
5380 excess_data: Vec::new()
5382 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5383 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5384 short_channel_id: 11,
5387 cltv_expiry_delta: 0,
5388 htlc_minimum_msat: 0,
5389 htlc_maximum_msat: 100_000,
5391 fee_proportional_millionths: 0,
5392 excess_data: Vec::new()
5395 // Path via {node7, node2} is channels {12, 13, 5}.
5396 // We already limited them to 200 sats (they are used twice for 100 sats).
5397 // Nothing to do here.
5400 // Attempt to route more than available results in a failure.
5401 let route_params = RouteParameters::from_payment_params_and_value(
5402 payment_params.clone(), 350_000);
5403 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5404 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5405 &scorer, &Default::default(), &random_seed_bytes) {
5406 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5407 } else { panic!(); }
5411 // Now, attempt to route 300 sats (exact amount we can route).
5412 // Our algorithm should provide us with these 3 paths, 100 sats each.
5413 let route_params = RouteParameters::from_payment_params_and_value(
5414 payment_params, 300_000);
5415 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5416 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5417 assert_eq!(route.paths.len(), 3);
5419 let mut total_amount_paid_msat = 0;
5420 for path in &route.paths {
5421 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5422 total_amount_paid_msat += path.final_value_msat();
5424 assert_eq!(total_amount_paid_msat, 300_000);
5430 fn mpp_cheaper_route_test() {
5431 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5432 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5433 let scorer = ln_test_utils::TestScorer::new();
5434 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5435 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5436 let config = UserConfig::default();
5437 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5438 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5441 // This test checks that if we have two cheaper paths and one more expensive path,
5442 // so that liquidity-wise any 2 of 3 combination is sufficient,
5443 // two cheaper paths will be taken.
5444 // These paths have equal available liquidity.
5446 // We need a combination of 3 paths:
5447 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5448 // Note that these paths overlap (channels 5, 12, 13).
5449 // Each path will have 100 sats capacity, those channels which
5450 // are used twice will have 200 sats capacity.
5452 // Disable other potential paths.
5453 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5454 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5455 short_channel_id: 2,
5458 cltv_expiry_delta: 0,
5459 htlc_minimum_msat: 0,
5460 htlc_maximum_msat: 100_000,
5462 fee_proportional_millionths: 0,
5463 excess_data: Vec::new()
5465 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5466 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5467 short_channel_id: 7,
5470 cltv_expiry_delta: 0,
5471 htlc_minimum_msat: 0,
5472 htlc_maximum_msat: 100_000,
5474 fee_proportional_millionths: 0,
5475 excess_data: Vec::new()
5478 // Path via {node0, node2} is channels {1, 3, 5}.
5479 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5480 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5481 short_channel_id: 1,
5484 cltv_expiry_delta: 0,
5485 htlc_minimum_msat: 0,
5486 htlc_maximum_msat: 100_000,
5488 fee_proportional_millionths: 0,
5489 excess_data: Vec::new()
5491 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5492 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5493 short_channel_id: 3,
5496 cltv_expiry_delta: 0,
5497 htlc_minimum_msat: 0,
5498 htlc_maximum_msat: 100_000,
5500 fee_proportional_millionths: 0,
5501 excess_data: Vec::new()
5504 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5505 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5506 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5507 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5508 short_channel_id: 5,
5511 cltv_expiry_delta: 0,
5512 htlc_minimum_msat: 0,
5513 htlc_maximum_msat: 200_000,
5515 fee_proportional_millionths: 0,
5516 excess_data: Vec::new()
5519 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5520 // Add 100 sats to the capacities of {12, 13}, because these channels
5521 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5522 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5523 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5524 short_channel_id: 12,
5527 cltv_expiry_delta: 0,
5528 htlc_minimum_msat: 0,
5529 htlc_maximum_msat: 200_000,
5531 fee_proportional_millionths: 0,
5532 excess_data: Vec::new()
5534 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5535 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5536 short_channel_id: 13,
5539 cltv_expiry_delta: 0,
5540 htlc_minimum_msat: 0,
5541 htlc_maximum_msat: 200_000,
5543 fee_proportional_millionths: 0,
5544 excess_data: Vec::new()
5547 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5548 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5549 short_channel_id: 6,
5552 cltv_expiry_delta: 0,
5553 htlc_minimum_msat: 0,
5554 htlc_maximum_msat: 100_000,
5555 fee_base_msat: 1_000,
5556 fee_proportional_millionths: 0,
5557 excess_data: Vec::new()
5559 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5560 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5561 short_channel_id: 11,
5564 cltv_expiry_delta: 0,
5565 htlc_minimum_msat: 0,
5566 htlc_maximum_msat: 100_000,
5568 fee_proportional_millionths: 0,
5569 excess_data: Vec::new()
5572 // Path via {node7, node2} is channels {12, 13, 5}.
5573 // We already limited them to 200 sats (they are used twice for 100 sats).
5574 // Nothing to do here.
5577 // Now, attempt to route 180 sats.
5578 // Our algorithm should provide us with these 2 paths.
5579 let route_params = RouteParameters::from_payment_params_and_value(
5580 payment_params, 180_000);
5581 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5582 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5583 assert_eq!(route.paths.len(), 2);
5585 let mut total_value_transferred_msat = 0;
5586 let mut total_paid_msat = 0;
5587 for path in &route.paths {
5588 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5589 total_value_transferred_msat += path.final_value_msat();
5590 for hop in &path.hops {
5591 total_paid_msat += hop.fee_msat;
5594 // If we paid fee, this would be higher.
5595 assert_eq!(total_value_transferred_msat, 180_000);
5596 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5597 assert_eq!(total_fees_paid, 0);
5602 fn fees_on_mpp_route_test() {
5603 // This test makes sure that MPP algorithm properly takes into account
5604 // fees charged on the channels, by making the fees impactful:
5605 // if the fee is not properly accounted for, the behavior is different.
5606 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5607 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5608 let scorer = ln_test_utils::TestScorer::new();
5609 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5610 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5611 let config = UserConfig::default();
5612 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5613 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5616 // We need a route consisting of 2 paths:
5617 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5618 // We will route 200 sats, Each path will have 100 sats capacity.
5620 // This test is not particularly stable: e.g.,
5621 // there's a way to route via {node0, node2, node4}.
5622 // It works while pathfinding is deterministic, but can be broken otherwise.
5623 // It's fine to ignore this concern for now.
5625 // Disable other potential paths.
5626 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5627 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5628 short_channel_id: 2,
5631 cltv_expiry_delta: 0,
5632 htlc_minimum_msat: 0,
5633 htlc_maximum_msat: 100_000,
5635 fee_proportional_millionths: 0,
5636 excess_data: Vec::new()
5639 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5640 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5641 short_channel_id: 7,
5644 cltv_expiry_delta: 0,
5645 htlc_minimum_msat: 0,
5646 htlc_maximum_msat: 100_000,
5648 fee_proportional_millionths: 0,
5649 excess_data: Vec::new()
5652 // Path via {node0, node2} is channels {1, 3, 5}.
5653 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5654 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5655 short_channel_id: 1,
5658 cltv_expiry_delta: 0,
5659 htlc_minimum_msat: 0,
5660 htlc_maximum_msat: 100_000,
5662 fee_proportional_millionths: 0,
5663 excess_data: Vec::new()
5665 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5666 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5667 short_channel_id: 3,
5670 cltv_expiry_delta: 0,
5671 htlc_minimum_msat: 0,
5672 htlc_maximum_msat: 100_000,
5674 fee_proportional_millionths: 0,
5675 excess_data: Vec::new()
5678 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5679 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5680 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5681 short_channel_id: 5,
5684 cltv_expiry_delta: 0,
5685 htlc_minimum_msat: 0,
5686 htlc_maximum_msat: 100_000,
5688 fee_proportional_millionths: 0,
5689 excess_data: Vec::new()
5692 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5693 // All channels should be 100 sats capacity. But for the fee experiment,
5694 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5695 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5696 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5697 // so no matter how large are other channels,
5698 // the whole path will be limited by 100 sats with just these 2 conditions:
5699 // - channel 12 capacity is 250 sats
5700 // - fee for channel 6 is 150 sats
5701 // Let's test this by enforcing these 2 conditions and removing other limits.
5702 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5703 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5704 short_channel_id: 12,
5707 cltv_expiry_delta: 0,
5708 htlc_minimum_msat: 0,
5709 htlc_maximum_msat: 250_000,
5711 fee_proportional_millionths: 0,
5712 excess_data: Vec::new()
5714 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5715 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5716 short_channel_id: 13,
5719 cltv_expiry_delta: 0,
5720 htlc_minimum_msat: 0,
5721 htlc_maximum_msat: MAX_VALUE_MSAT,
5723 fee_proportional_millionths: 0,
5724 excess_data: Vec::new()
5727 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5728 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5729 short_channel_id: 6,
5732 cltv_expiry_delta: 0,
5733 htlc_minimum_msat: 0,
5734 htlc_maximum_msat: MAX_VALUE_MSAT,
5735 fee_base_msat: 150_000,
5736 fee_proportional_millionths: 0,
5737 excess_data: Vec::new()
5739 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5740 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5741 short_channel_id: 11,
5744 cltv_expiry_delta: 0,
5745 htlc_minimum_msat: 0,
5746 htlc_maximum_msat: MAX_VALUE_MSAT,
5748 fee_proportional_millionths: 0,
5749 excess_data: Vec::new()
5753 // Attempt to route more than available results in a failure.
5754 let route_params = RouteParameters::from_payment_params_and_value(
5755 payment_params.clone(), 210_000);
5756 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5757 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5758 &scorer, &Default::default(), &random_seed_bytes) {
5759 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5760 } else { panic!(); }
5764 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5765 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5766 max_total_routing_fee_msat: Some(149_999) };
5767 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5768 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5769 &scorer, &Default::default(), &random_seed_bytes) {
5770 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5771 } else { panic!(); }
5775 // Now, attempt to route 200 sats (exact amount we can route).
5776 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5777 max_total_routing_fee_msat: Some(150_000) };
5778 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5779 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5780 assert_eq!(route.paths.len(), 2);
5782 let mut total_amount_paid_msat = 0;
5783 for path in &route.paths {
5784 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5785 total_amount_paid_msat += path.final_value_msat();
5787 assert_eq!(total_amount_paid_msat, 200_000);
5788 assert_eq!(route.get_total_fees(), 150_000);
5793 fn mpp_with_last_hops() {
5794 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5795 // via a single last-hop route hint, we'd fail to route if we first collected routes
5796 // totaling close but not quite enough to fund the full payment.
5798 // This was because we considered last-hop hints to have exactly the sought payment amount
5799 // instead of the amount we were trying to collect, needlessly limiting our path searching
5800 // at the very first hop.
5802 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5803 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5804 // to only have the remaining to-collect amount in available liquidity.
5806 // This bug appeared in production in some specific channel configurations.
5807 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5808 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5809 let scorer = ln_test_utils::TestScorer::new();
5810 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5811 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5812 let config = UserConfig::default();
5813 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
5814 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
5815 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5816 src_node_id: nodes[2],
5817 short_channel_id: 42,
5818 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5819 cltv_expiry_delta: 42,
5820 htlc_minimum_msat: None,
5821 htlc_maximum_msat: None,
5822 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5824 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5825 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5826 // would first use the no-fee route and then fail to find a path along the second route as
5827 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5828 // under 5% of our payment amount.
5829 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5830 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5831 short_channel_id: 1,
5834 cltv_expiry_delta: (5 << 4) | 5,
5835 htlc_minimum_msat: 0,
5836 htlc_maximum_msat: 99_000,
5837 fee_base_msat: u32::max_value(),
5838 fee_proportional_millionths: u32::max_value(),
5839 excess_data: Vec::new()
5841 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5842 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5843 short_channel_id: 2,
5846 cltv_expiry_delta: (5 << 4) | 3,
5847 htlc_minimum_msat: 0,
5848 htlc_maximum_msat: 99_000,
5849 fee_base_msat: u32::max_value(),
5850 fee_proportional_millionths: u32::max_value(),
5851 excess_data: Vec::new()
5853 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5854 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5855 short_channel_id: 4,
5858 cltv_expiry_delta: (4 << 4) | 1,
5859 htlc_minimum_msat: 0,
5860 htlc_maximum_msat: MAX_VALUE_MSAT,
5862 fee_proportional_millionths: 0,
5863 excess_data: Vec::new()
5865 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5866 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5867 short_channel_id: 13,
5869 flags: 0|2, // Channel disabled
5870 cltv_expiry_delta: (13 << 4) | 1,
5871 htlc_minimum_msat: 0,
5872 htlc_maximum_msat: MAX_VALUE_MSAT,
5874 fee_proportional_millionths: 2000000,
5875 excess_data: Vec::new()
5878 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5880 let route_params = RouteParameters::from_payment_params_and_value(
5881 payment_params, 100_000);
5882 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5883 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5884 assert_eq!(route.paths.len(), 2);
5885 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5886 // Paths are manually ordered ordered by SCID, so:
5887 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5888 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5889 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5890 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5891 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5892 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5893 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5894 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5895 assert_eq!(route.get_total_fees(), 1);
5896 assert_eq!(route.get_total_amount(), 100_000);
5900 fn drop_lowest_channel_mpp_route_test() {
5901 // This test checks that low-capacity channel is dropped when after
5902 // path finding we realize that we found more capacity than we need.
5903 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5904 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5905 let scorer = ln_test_utils::TestScorer::new();
5906 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5907 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5908 let config = UserConfig::default();
5909 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5910 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5912 .with_max_channel_saturation_power_of_half(0);
5914 // We need a route consisting of 3 paths:
5915 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5917 // The first and the second paths should be sufficient, but the third should be
5918 // cheaper, so that we select it but drop later.
5920 // First, we set limits on these (previously unlimited) channels.
5921 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5923 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5924 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5925 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5926 short_channel_id: 1,
5929 cltv_expiry_delta: 0,
5930 htlc_minimum_msat: 0,
5931 htlc_maximum_msat: 100_000,
5933 fee_proportional_millionths: 0,
5934 excess_data: Vec::new()
5936 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5937 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5938 short_channel_id: 3,
5941 cltv_expiry_delta: 0,
5942 htlc_minimum_msat: 0,
5943 htlc_maximum_msat: 50_000,
5945 fee_proportional_millionths: 0,
5946 excess_data: Vec::new()
5949 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5950 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5951 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5952 short_channel_id: 12,
5955 cltv_expiry_delta: 0,
5956 htlc_minimum_msat: 0,
5957 htlc_maximum_msat: 60_000,
5959 fee_proportional_millionths: 0,
5960 excess_data: Vec::new()
5962 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5963 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5964 short_channel_id: 13,
5967 cltv_expiry_delta: 0,
5968 htlc_minimum_msat: 0,
5969 htlc_maximum_msat: 60_000,
5971 fee_proportional_millionths: 0,
5972 excess_data: Vec::new()
5975 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5976 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5977 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5978 short_channel_id: 2,
5981 cltv_expiry_delta: 0,
5982 htlc_minimum_msat: 0,
5983 htlc_maximum_msat: 20_000,
5985 fee_proportional_millionths: 0,
5986 excess_data: Vec::new()
5988 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5989 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5990 short_channel_id: 4,
5993 cltv_expiry_delta: 0,
5994 htlc_minimum_msat: 0,
5995 htlc_maximum_msat: 20_000,
5997 fee_proportional_millionths: 0,
5998 excess_data: Vec::new()
6002 // Attempt to route more than available results in a failure.
6003 let route_params = RouteParameters::from_payment_params_and_value(
6004 payment_params.clone(), 150_000);
6005 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
6006 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
6007 &scorer, &Default::default(), &random_seed_bytes) {
6008 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6009 } else { panic!(); }
6013 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
6014 // Our algorithm should provide us with these 3 paths.
6015 let route_params = RouteParameters::from_payment_params_and_value(
6016 payment_params.clone(), 125_000);
6017 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6018 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6019 assert_eq!(route.paths.len(), 3);
6020 let mut total_amount_paid_msat = 0;
6021 for path in &route.paths {
6022 assert_eq!(path.hops.len(), 2);
6023 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6024 total_amount_paid_msat += path.final_value_msat();
6026 assert_eq!(total_amount_paid_msat, 125_000);
6030 // Attempt to route without the last small cheap channel
6031 let route_params = RouteParameters::from_payment_params_and_value(
6032 payment_params, 90_000);
6033 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6034 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6035 assert_eq!(route.paths.len(), 2);
6036 let mut total_amount_paid_msat = 0;
6037 for path in &route.paths {
6038 assert_eq!(path.hops.len(), 2);
6039 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6040 total_amount_paid_msat += path.final_value_msat();
6042 assert_eq!(total_amount_paid_msat, 90_000);
6047 fn min_criteria_consistency() {
6048 // Test that we don't use an inconsistent metric between updating and walking nodes during
6049 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
6050 // was updated with a different criterion from the heap sorting, resulting in loops in
6051 // calculated paths. We test for that specific case here.
6053 // We construct a network that looks like this:
6055 // node2 -1(3)2- node3
6059 // node1 -1(5)2- node4 -1(1)2- node6
6065 // We create a loop on the side of our real path - our destination is node 6, with a
6066 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
6067 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
6068 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
6069 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
6070 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
6071 // "previous hop" being set to node 3, creating a loop in the path.
6072 let secp_ctx = Secp256k1::new();
6073 let logger = Arc::new(ln_test_utils::TestLogger::new());
6074 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6075 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
6076 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6077 let scorer = ln_test_utils::TestScorer::new();
6078 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6079 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6080 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
6082 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
6083 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6084 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6085 short_channel_id: 6,
6088 cltv_expiry_delta: (6 << 4) | 0,
6089 htlc_minimum_msat: 0,
6090 htlc_maximum_msat: MAX_VALUE_MSAT,
6092 fee_proportional_millionths: 0,
6093 excess_data: Vec::new()
6095 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
6097 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
6098 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6099 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6100 short_channel_id: 5,
6103 cltv_expiry_delta: (5 << 4) | 0,
6104 htlc_minimum_msat: 0,
6105 htlc_maximum_msat: MAX_VALUE_MSAT,
6107 fee_proportional_millionths: 0,
6108 excess_data: Vec::new()
6110 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
6112 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
6113 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6114 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6115 short_channel_id: 4,
6118 cltv_expiry_delta: (4 << 4) | 0,
6119 htlc_minimum_msat: 0,
6120 htlc_maximum_msat: MAX_VALUE_MSAT,
6122 fee_proportional_millionths: 0,
6123 excess_data: Vec::new()
6125 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
6127 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
6128 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
6129 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6130 short_channel_id: 3,
6133 cltv_expiry_delta: (3 << 4) | 0,
6134 htlc_minimum_msat: 0,
6135 htlc_maximum_msat: MAX_VALUE_MSAT,
6137 fee_proportional_millionths: 0,
6138 excess_data: Vec::new()
6140 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
6142 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
6143 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
6144 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6145 short_channel_id: 2,
6148 cltv_expiry_delta: (2 << 4) | 0,
6149 htlc_minimum_msat: 0,
6150 htlc_maximum_msat: MAX_VALUE_MSAT,
6152 fee_proportional_millionths: 0,
6153 excess_data: Vec::new()
6156 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6157 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6158 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6159 short_channel_id: 1,
6162 cltv_expiry_delta: (1 << 4) | 0,
6163 htlc_minimum_msat: 100,
6164 htlc_maximum_msat: MAX_VALUE_MSAT,
6166 fee_proportional_millionths: 0,
6167 excess_data: Vec::new()
6169 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6172 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6173 let route_params = RouteParameters::from_payment_params_and_value(
6174 payment_params, 10_000);
6175 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6176 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6177 assert_eq!(route.paths.len(), 1);
6178 assert_eq!(route.paths[0].hops.len(), 3);
6180 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6181 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6182 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6183 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6184 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6185 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6187 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6188 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6189 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6190 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6191 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6192 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6194 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6195 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6196 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6197 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6198 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6199 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6205 fn exact_fee_liquidity_limit() {
6206 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6207 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6208 // we calculated fees on a higher value, resulting in us ignoring such paths.
6209 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6210 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6211 let scorer = ln_test_utils::TestScorer::new();
6212 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6213 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6214 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6216 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6218 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6219 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6220 short_channel_id: 2,
6223 cltv_expiry_delta: 0,
6224 htlc_minimum_msat: 0,
6225 htlc_maximum_msat: 85_000,
6227 fee_proportional_millionths: 0,
6228 excess_data: Vec::new()
6231 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6232 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6233 short_channel_id: 12,
6236 cltv_expiry_delta: (4 << 4) | 1,
6237 htlc_minimum_msat: 0,
6238 htlc_maximum_msat: 270_000,
6240 fee_proportional_millionths: 1000000,
6241 excess_data: Vec::new()
6245 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6246 // 200% fee charged channel 13 in the 1-to-2 direction.
6247 let mut route_params = RouteParameters::from_payment_params_and_value(
6248 payment_params, 90_000);
6249 route_params.max_total_routing_fee_msat = Some(90_000*2);
6250 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6251 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6252 assert_eq!(route.paths.len(), 1);
6253 assert_eq!(route.paths[0].hops.len(), 2);
6255 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6256 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6257 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6258 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6259 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6260 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6262 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6263 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6264 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6265 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6266 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6267 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6272 fn htlc_max_reduction_below_min() {
6273 // Test that if, while walking the graph, we reduce the value being sent to meet an
6274 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6275 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6276 // resulting in us thinking there is no possible path, even if other paths exist.
6277 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6278 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6279 let scorer = ln_test_utils::TestScorer::new();
6280 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6281 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6282 let config = UserConfig::default();
6283 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6284 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6287 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6288 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6289 // then try to send 90_000.
6290 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6291 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6292 short_channel_id: 2,
6295 cltv_expiry_delta: 0,
6296 htlc_minimum_msat: 0,
6297 htlc_maximum_msat: 80_000,
6299 fee_proportional_millionths: 0,
6300 excess_data: Vec::new()
6302 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6303 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6304 short_channel_id: 4,
6307 cltv_expiry_delta: (4 << 4) | 1,
6308 htlc_minimum_msat: 90_000,
6309 htlc_maximum_msat: MAX_VALUE_MSAT,
6311 fee_proportional_millionths: 0,
6312 excess_data: Vec::new()
6316 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6317 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6318 // expensive) channels 12-13 path.
6319 let mut route_params = RouteParameters::from_payment_params_and_value(
6320 payment_params, 90_000);
6321 route_params.max_total_routing_fee_msat = Some(90_000*2);
6322 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6323 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6324 assert_eq!(route.paths.len(), 1);
6325 assert_eq!(route.paths[0].hops.len(), 2);
6327 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6328 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6329 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6330 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6331 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6332 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6334 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6335 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6336 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6337 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6338 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6339 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6344 fn multiple_direct_first_hops() {
6345 // Previously we'd only ever considered one first hop path per counterparty.
6346 // However, as we don't restrict users to one channel per peer, we really need to support
6347 // looking at all first hop paths.
6348 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6349 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6350 // route over multiple channels with the same first hop.
6351 let secp_ctx = Secp256k1::new();
6352 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6353 let logger = Arc::new(ln_test_utils::TestLogger::new());
6354 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6355 let scorer = ln_test_utils::TestScorer::new();
6356 let config = UserConfig::default();
6357 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6358 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6360 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6361 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6364 let route_params = RouteParameters::from_payment_params_and_value(
6365 payment_params.clone(), 100_000);
6366 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6367 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6368 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6369 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6370 assert_eq!(route.paths.len(), 1);
6371 assert_eq!(route.paths[0].hops.len(), 1);
6373 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6374 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6375 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6378 let route_params = RouteParameters::from_payment_params_and_value(
6379 payment_params.clone(), 100_000);
6380 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6381 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6382 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6383 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6384 assert_eq!(route.paths.len(), 2);
6385 assert_eq!(route.paths[0].hops.len(), 1);
6386 assert_eq!(route.paths[1].hops.len(), 1);
6388 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6389 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6391 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6392 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6394 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6395 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6399 // If we have a bunch of outbound channels to the same node, where most are not
6400 // sufficient to pay the full payment, but one is, we should default to just using the
6401 // one single channel that has sufficient balance, avoiding MPP.
6403 // If we have several options above the 3xpayment value threshold, we should pick the
6404 // smallest of them, avoiding further fragmenting our available outbound balance to
6406 let route_params = RouteParameters::from_payment_params_and_value(
6407 payment_params, 100_000);
6408 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6409 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6410 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6411 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6412 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6413 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6414 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6415 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6416 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6417 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6418 assert_eq!(route.paths.len(), 1);
6419 assert_eq!(route.paths[0].hops.len(), 1);
6421 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6422 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6423 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6428 fn prefers_shorter_route_with_higher_fees() {
6429 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6430 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6431 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6433 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6434 let scorer = ln_test_utils::TestScorer::new();
6435 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6436 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6437 let route_params = RouteParameters::from_payment_params_and_value(
6438 payment_params.clone(), 100);
6439 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6440 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6441 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6443 assert_eq!(route.get_total_fees(), 100);
6444 assert_eq!(route.get_total_amount(), 100);
6445 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6447 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6448 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6449 let scorer = FixedPenaltyScorer::with_penalty(100);
6450 let route_params = RouteParameters::from_payment_params_and_value(
6451 payment_params, 100);
6452 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6453 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6454 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6456 assert_eq!(route.get_total_fees(), 300);
6457 assert_eq!(route.get_total_amount(), 100);
6458 assert_eq!(path, vec![2, 4, 7, 10]);
6461 struct BadChannelScorer {
6462 short_channel_id: u64,
6466 impl Writeable for BadChannelScorer {
6467 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6469 impl ScoreLookUp for BadChannelScorer {
6470 type ScoreParams = ();
6471 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6472 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6476 struct BadNodeScorer {
6481 impl Writeable for BadNodeScorer {
6482 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6485 impl ScoreLookUp for BadNodeScorer {
6486 type ScoreParams = ();
6487 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6488 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6493 fn avoids_routing_through_bad_channels_and_nodes() {
6494 let (secp_ctx, network, _, _, logger) = build_graph();
6495 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6496 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6497 let network_graph = network.read_only();
6499 // A path to nodes[6] exists when no penalties are applied to any channel.
6500 let scorer = ln_test_utils::TestScorer::new();
6501 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6502 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6503 let route_params = RouteParameters::from_payment_params_and_value(
6504 payment_params, 100);
6505 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6506 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6507 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6509 assert_eq!(route.get_total_fees(), 100);
6510 assert_eq!(route.get_total_amount(), 100);
6511 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6513 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6514 let scorer = BadChannelScorer { short_channel_id: 6 };
6515 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6516 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6517 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6519 assert_eq!(route.get_total_fees(), 300);
6520 assert_eq!(route.get_total_amount(), 100);
6521 assert_eq!(path, vec![2, 4, 7, 10]);
6523 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6524 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6525 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6526 &scorer, &Default::default(), &random_seed_bytes) {
6527 Err(LightningError { err, .. } ) => {
6528 assert_eq!(err, "Failed to find a path to the given destination");
6530 Ok(_) => panic!("Expected error"),
6535 fn total_fees_single_path() {
6537 paths: vec![Path { hops: vec![
6539 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6540 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6541 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6544 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6545 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6546 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6549 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6550 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6551 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6553 ], blinded_tail: None }],
6557 assert_eq!(route.get_total_fees(), 250);
6558 assert_eq!(route.get_total_amount(), 225);
6562 fn total_fees_multi_path() {
6564 paths: vec![Path { hops: vec![
6566 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6567 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6568 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6571 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6572 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6573 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6575 ], blinded_tail: None }, Path { hops: vec![
6577 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6578 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6579 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6582 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6583 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6584 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6586 ], blinded_tail: None }],
6590 assert_eq!(route.get_total_fees(), 200);
6591 assert_eq!(route.get_total_amount(), 300);
6595 fn total_empty_route_no_panic() {
6596 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6597 // would both panic if the route was completely empty. We test to ensure they return 0
6598 // here, even though its somewhat nonsensical as a route.
6599 let route = Route { paths: Vec::new(), route_params: None };
6601 assert_eq!(route.get_total_fees(), 0);
6602 assert_eq!(route.get_total_amount(), 0);
6606 fn limits_total_cltv_delta() {
6607 let (secp_ctx, network, _, _, logger) = build_graph();
6608 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6609 let network_graph = network.read_only();
6611 let scorer = ln_test_utils::TestScorer::new();
6613 // Make sure that generally there is at least one route available
6614 let feasible_max_total_cltv_delta = 1008;
6615 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6616 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6617 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6618 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6619 let route_params = RouteParameters::from_payment_params_and_value(
6620 feasible_payment_params, 100);
6621 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6622 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6623 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6624 assert_ne!(path.len(), 0);
6626 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6627 let fail_max_total_cltv_delta = 23;
6628 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6629 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6630 let route_params = RouteParameters::from_payment_params_and_value(
6631 fail_payment_params, 100);
6632 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6633 &Default::default(), &random_seed_bytes)
6635 Err(LightningError { err, .. } ) => {
6636 assert_eq!(err, "Failed to find a path to the given destination");
6638 Ok(_) => panic!("Expected error"),
6643 fn avoids_recently_failed_paths() {
6644 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6645 // randomly inserting channels into it until we can't find a route anymore.
6646 let (secp_ctx, network, _, _, logger) = build_graph();
6647 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6648 let network_graph = network.read_only();
6650 let scorer = ln_test_utils::TestScorer::new();
6651 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6652 .with_max_path_count(1);
6653 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6654 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6656 // We should be able to find a route initially, and then after we fail a few random
6657 // channels eventually we won't be able to any longer.
6658 let route_params = RouteParameters::from_payment_params_and_value(
6659 payment_params.clone(), 100);
6660 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6661 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6663 let route_params = RouteParameters::from_payment_params_and_value(
6664 payment_params.clone(), 100);
6665 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6666 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6668 for chan in route.paths[0].hops.iter() {
6669 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6671 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6672 % route.paths[0].hops.len();
6673 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6679 fn limits_path_length() {
6680 let (secp_ctx, network, _, _, logger) = build_line_graph();
6681 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6682 let network_graph = network.read_only();
6684 let scorer = ln_test_utils::TestScorer::new();
6685 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6686 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6688 // First check we can actually create a long route on this graph.
6689 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6690 let route_params = RouteParameters::from_payment_params_and_value(
6691 feasible_payment_params, 100);
6692 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6693 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6694 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6695 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6697 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6698 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6699 let route_params = RouteParameters::from_payment_params_and_value(
6700 fail_payment_params, 100);
6701 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6702 &Default::default(), &random_seed_bytes)
6704 Err(LightningError { err, .. } ) => {
6705 assert_eq!(err, "Failed to find a path to the given destination");
6707 Ok(_) => panic!("Expected error"),
6712 fn adds_and_limits_cltv_offset() {
6713 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6714 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6716 let scorer = ln_test_utils::TestScorer::new();
6718 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6719 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6720 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6721 let route_params = RouteParameters::from_payment_params_and_value(
6722 payment_params.clone(), 100);
6723 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6724 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6725 assert_eq!(route.paths.len(), 1);
6727 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6729 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6730 let mut route_default = route.clone();
6731 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6732 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6733 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6734 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6735 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6737 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6738 let mut route_limited = route.clone();
6739 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6740 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6741 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6742 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6743 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6747 fn adds_plausible_cltv_offset() {
6748 let (secp_ctx, network, _, _, logger) = build_graph();
6749 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6750 let network_graph = network.read_only();
6751 let network_nodes = network_graph.nodes();
6752 let network_channels = network_graph.channels();
6753 let scorer = ln_test_utils::TestScorer::new();
6754 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6755 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6756 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6758 let route_params = RouteParameters::from_payment_params_and_value(
6759 payment_params.clone(), 100);
6760 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6761 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6762 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6764 let mut path_plausibility = vec![];
6766 for p in route.paths {
6767 // 1. Select random observation point
6768 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6769 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6771 prng.process_in_place(&mut random_bytes);
6772 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6773 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6775 // 2. Calculate what CLTV expiry delta we would observe there
6776 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6778 // 3. Starting from the observation point, find candidate paths
6779 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6780 candidates.push_back((observation_point, vec![]));
6782 let mut found_plausible_candidate = false;
6784 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6785 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6786 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6787 found_plausible_candidate = true;
6788 break 'candidate_loop;
6792 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6793 for channel_id in &cur_node.channels {
6794 if let Some(channel_info) = network_channels.get(&channel_id) {
6795 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6796 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6797 if cur_path_cltv_deltas.iter().sum::<u32>()
6798 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6799 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6800 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6801 candidates.push_back((*next_id, new_path_cltv_deltas));
6809 path_plausibility.push(found_plausible_candidate);
6811 assert!(path_plausibility.iter().all(|x| *x));
6815 fn builds_correct_path_from_hops() {
6816 let (secp_ctx, network, _, _, logger) = build_graph();
6817 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6818 let network_graph = network.read_only();
6820 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6821 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6823 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6824 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6825 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6826 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6827 Arc::clone(&logger), &random_seed_bytes).unwrap();
6828 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6829 assert_eq!(hops.len(), route.paths[0].hops.len());
6830 for (idx, hop_pubkey) in hops.iter().enumerate() {
6831 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6836 fn avoids_saturating_channels() {
6837 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6838 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6839 let decay_params = ProbabilisticScoringDecayParameters::default();
6840 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6842 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6843 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6844 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6845 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6846 short_channel_id: 4,
6849 cltv_expiry_delta: (4 << 4) | 1,
6850 htlc_minimum_msat: 0,
6851 htlc_maximum_msat: 250_000_000,
6853 fee_proportional_millionths: 0,
6854 excess_data: Vec::new()
6856 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6857 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6858 short_channel_id: 13,
6861 cltv_expiry_delta: (13 << 4) | 1,
6862 htlc_minimum_msat: 0,
6863 htlc_maximum_msat: 250_000_000,
6865 fee_proportional_millionths: 0,
6866 excess_data: Vec::new()
6869 let config = UserConfig::default();
6870 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6871 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6873 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6874 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6875 // 100,000 sats is less than the available liquidity on each channel, set above.
6876 let route_params = RouteParameters::from_payment_params_and_value(
6877 payment_params, 100_000_000);
6878 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6879 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6880 assert_eq!(route.paths.len(), 2);
6881 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6882 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6885 #[cfg(not(feature = "no-std"))]
6886 pub(super) fn random_init_seed() -> u64 {
6887 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6888 use core::hash::{BuildHasher, Hasher};
6889 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6890 println!("Using seed of {}", seed);
6895 #[cfg(not(feature = "no-std"))]
6896 fn generate_routes() {
6897 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6899 let logger = ln_test_utils::TestLogger::new();
6900 let graph = match super::bench_utils::read_network_graph(&logger) {
6908 let params = ProbabilisticScoringFeeParameters::default();
6909 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6910 let features = super::Bolt11InvoiceFeatures::empty();
6912 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6916 #[cfg(not(feature = "no-std"))]
6917 fn generate_routes_mpp() {
6918 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6920 let logger = ln_test_utils::TestLogger::new();
6921 let graph = match super::bench_utils::read_network_graph(&logger) {
6929 let params = ProbabilisticScoringFeeParameters::default();
6930 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6931 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6933 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6937 #[cfg(not(feature = "no-std"))]
6938 fn generate_large_mpp_routes() {
6939 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6941 let logger = ln_test_utils::TestLogger::new();
6942 let graph = match super::bench_utils::read_network_graph(&logger) {
6950 let params = ProbabilisticScoringFeeParameters::default();
6951 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6952 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6954 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6958 fn honors_manual_penalties() {
6959 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6960 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6962 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6963 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6965 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6966 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6968 // First check set manual penalties are returned by the scorer.
6969 let usage = ChannelUsage {
6971 inflight_htlc_msat: 0,
6972 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6974 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6975 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6976 let network_graph = network_graph.read_only();
6977 let channels = network_graph.channels();
6978 let channel = channels.get(&5).unwrap();
6979 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
6980 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop {
6982 short_channel_id: 5,
6984 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
6986 // Then check we can get a normal route
6987 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6988 let route_params = RouteParameters::from_payment_params_and_value(
6989 payment_params, 100);
6990 let route = get_route(&our_id, &route_params, &network_graph, None,
6991 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6992 assert!(route.is_ok());
6994 // Then check that we can't get a route if we ban an intermediate node.
6995 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6996 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6997 assert!(route.is_err());
6999 // Finally make sure we can route again, when we remove the ban.
7000 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
7001 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
7002 assert!(route.is_ok());
7006 fn abide_by_route_hint_max_htlc() {
7007 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
7008 // params in the final route.
7009 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7010 let netgraph = network_graph.read_only();
7011 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7012 let scorer = ln_test_utils::TestScorer::new();
7013 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7014 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7015 let config = UserConfig::default();
7017 let max_htlc_msat = 50_000;
7018 let route_hint_1 = RouteHint(vec![RouteHintHop {
7019 src_node_id: nodes[2],
7020 short_channel_id: 42,
7023 proportional_millionths: 0,
7025 cltv_expiry_delta: 10,
7026 htlc_minimum_msat: None,
7027 htlc_maximum_msat: Some(max_htlc_msat),
7029 let dest_node_id = ln_test_utils::pubkey(42);
7030 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7031 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
7032 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7035 // Make sure we'll error if our route hints don't have enough liquidity according to their
7036 // htlc_maximum_msat.
7037 let mut route_params = RouteParameters::from_payment_params_and_value(
7038 payment_params, max_htlc_msat + 1);
7039 route_params.max_total_routing_fee_msat = None;
7040 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
7041 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
7044 assert_eq!(err, "Failed to find a sufficient route to the given destination");
7045 } else { panic!(); }
7047 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
7048 let mut route_hint_2 = route_hint_1.clone();
7049 route_hint_2.0[0].short_channel_id = 43;
7050 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7051 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7052 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7054 let mut route_params = RouteParameters::from_payment_params_and_value(
7055 payment_params, max_htlc_msat + 1);
7056 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
7057 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
7058 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7059 assert_eq!(route.paths.len(), 2);
7060 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7061 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7065 fn direct_channel_to_hints_with_max_htlc() {
7066 // Check that if we have a first hop channel peer that's connected to multiple provided route
7067 // hints, that we properly split the payment between the route hints if needed.
7068 let logger = Arc::new(ln_test_utils::TestLogger::new());
7069 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7070 let scorer = ln_test_utils::TestScorer::new();
7071 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7072 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7073 let config = UserConfig::default();
7075 let our_node_id = ln_test_utils::pubkey(42);
7076 let intermed_node_id = ln_test_utils::pubkey(43);
7077 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7079 let amt_msat = 900_000;
7080 let max_htlc_msat = 500_000;
7081 let route_hint_1 = RouteHint(vec![RouteHintHop {
7082 src_node_id: intermed_node_id,
7083 short_channel_id: 44,
7086 proportional_millionths: 0,
7088 cltv_expiry_delta: 10,
7089 htlc_minimum_msat: None,
7090 htlc_maximum_msat: Some(max_htlc_msat),
7092 src_node_id: intermed_node_id,
7093 short_channel_id: 45,
7096 proportional_millionths: 0,
7098 cltv_expiry_delta: 10,
7099 htlc_minimum_msat: None,
7100 // Check that later route hint max htlcs don't override earlier ones
7101 htlc_maximum_msat: Some(max_htlc_msat - 50),
7103 let mut route_hint_2 = route_hint_1.clone();
7104 route_hint_2.0[0].short_channel_id = 46;
7105 route_hint_2.0[1].short_channel_id = 47;
7106 let dest_node_id = ln_test_utils::pubkey(44);
7107 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7108 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7109 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7112 let route_params = RouteParameters::from_payment_params_and_value(
7113 payment_params, amt_msat);
7114 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7115 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7116 &Default::default(), &random_seed_bytes).unwrap();
7117 assert_eq!(route.paths.len(), 2);
7118 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7119 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7120 assert_eq!(route.get_total_amount(), amt_msat);
7122 // Re-run but with two first hop channels connected to the same route hint peers that must be
7124 let first_hops = vec![
7125 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7126 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7128 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7129 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7130 &Default::default(), &random_seed_bytes).unwrap();
7131 assert_eq!(route.paths.len(), 2);
7132 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7133 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7134 assert_eq!(route.get_total_amount(), amt_msat);
7136 // Make sure this works for blinded route hints.
7137 let blinded_path = BlindedPath {
7138 introduction_node_id: intermed_node_id,
7139 blinding_point: ln_test_utils::pubkey(42),
7141 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
7142 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
7145 let blinded_payinfo = BlindedPayInfo {
7147 fee_proportional_millionths: 0,
7148 htlc_minimum_msat: 1,
7149 htlc_maximum_msat: max_htlc_msat,
7150 cltv_expiry_delta: 10,
7151 features: BlindedHopFeatures::empty(),
7153 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7154 let payment_params = PaymentParameters::blinded(vec![
7155 (blinded_payinfo.clone(), blinded_path.clone()),
7156 (blinded_payinfo.clone(), blinded_path.clone())])
7157 .with_bolt12_features(bolt12_features).unwrap();
7158 let route_params = RouteParameters::from_payment_params_and_value(
7159 payment_params, amt_msat);
7160 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7161 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7162 &Default::default(), &random_seed_bytes).unwrap();
7163 assert_eq!(route.paths.len(), 2);
7164 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7165 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7166 assert_eq!(route.get_total_amount(), amt_msat);
7170 fn blinded_route_ser() {
7171 let blinded_path_1 = BlindedPath {
7172 introduction_node_id: ln_test_utils::pubkey(42),
7173 blinding_point: ln_test_utils::pubkey(43),
7175 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7176 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7179 let blinded_path_2 = BlindedPath {
7180 introduction_node_id: ln_test_utils::pubkey(46),
7181 blinding_point: ln_test_utils::pubkey(47),
7183 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7184 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7187 // (De)serialize a Route with 1 blinded path out of two total paths.
7188 let mut route = Route { paths: vec![Path {
7189 hops: vec![RouteHop {
7190 pubkey: ln_test_utils::pubkey(50),
7191 node_features: NodeFeatures::empty(),
7192 short_channel_id: 42,
7193 channel_features: ChannelFeatures::empty(),
7195 cltv_expiry_delta: 0,
7196 maybe_announced_channel: true,
7198 blinded_tail: Some(BlindedTail {
7199 hops: blinded_path_1.blinded_hops,
7200 blinding_point: blinded_path_1.blinding_point,
7201 excess_final_cltv_expiry_delta: 40,
7202 final_value_msat: 100,
7204 hops: vec![RouteHop {
7205 pubkey: ln_test_utils::pubkey(51),
7206 node_features: NodeFeatures::empty(),
7207 short_channel_id: 43,
7208 channel_features: ChannelFeatures::empty(),
7210 cltv_expiry_delta: 0,
7211 maybe_announced_channel: true,
7212 }], blinded_tail: None }],
7215 let encoded_route = route.encode();
7216 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7217 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7218 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7220 // (De)serialize a Route with two paths, each containing a blinded tail.
7221 route.paths[1].blinded_tail = Some(BlindedTail {
7222 hops: blinded_path_2.blinded_hops,
7223 blinding_point: blinded_path_2.blinding_point,
7224 excess_final_cltv_expiry_delta: 41,
7225 final_value_msat: 101,
7227 let encoded_route = route.encode();
7228 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7229 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7230 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7234 fn blinded_path_inflight_processing() {
7235 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7236 // account for the blinded tail's final amount_msat.
7237 let mut inflight_htlcs = InFlightHtlcs::new();
7238 let blinded_path = BlindedPath {
7239 introduction_node_id: ln_test_utils::pubkey(43),
7240 blinding_point: ln_test_utils::pubkey(48),
7241 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7244 hops: vec![RouteHop {
7245 pubkey: ln_test_utils::pubkey(42),
7246 node_features: NodeFeatures::empty(),
7247 short_channel_id: 42,
7248 channel_features: ChannelFeatures::empty(),
7250 cltv_expiry_delta: 0,
7251 maybe_announced_channel: false,
7254 pubkey: blinded_path.introduction_node_id,
7255 node_features: NodeFeatures::empty(),
7256 short_channel_id: 43,
7257 channel_features: ChannelFeatures::empty(),
7259 cltv_expiry_delta: 0,
7260 maybe_announced_channel: false,
7262 blinded_tail: Some(BlindedTail {
7263 hops: blinded_path.blinded_hops,
7264 blinding_point: blinded_path.blinding_point,
7265 excess_final_cltv_expiry_delta: 0,
7266 final_value_msat: 200,
7269 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7270 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7271 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7275 fn blinded_path_cltv_shadow_offset() {
7276 // Make sure we add a shadow offset when sending to blinded paths.
7277 let blinded_path = BlindedPath {
7278 introduction_node_id: ln_test_utils::pubkey(43),
7279 blinding_point: ln_test_utils::pubkey(44),
7281 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7282 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7285 let mut route = Route { paths: vec![Path {
7286 hops: vec![RouteHop {
7287 pubkey: ln_test_utils::pubkey(42),
7288 node_features: NodeFeatures::empty(),
7289 short_channel_id: 42,
7290 channel_features: ChannelFeatures::empty(),
7292 cltv_expiry_delta: 0,
7293 maybe_announced_channel: false,
7296 pubkey: blinded_path.introduction_node_id,
7297 node_features: NodeFeatures::empty(),
7298 short_channel_id: 43,
7299 channel_features: ChannelFeatures::empty(),
7301 cltv_expiry_delta: 0,
7302 maybe_announced_channel: false,
7305 blinded_tail: Some(BlindedTail {
7306 hops: blinded_path.blinded_hops,
7307 blinding_point: blinded_path.blinding_point,
7308 excess_final_cltv_expiry_delta: 0,
7309 final_value_msat: 200,
7311 }], route_params: None};
7313 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7314 let (_, network_graph, _, _, _) = build_line_graph();
7315 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7316 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7317 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7321 fn simple_blinded_route_hints() {
7322 do_simple_blinded_route_hints(1);
7323 do_simple_blinded_route_hints(2);
7324 do_simple_blinded_route_hints(3);
7327 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7328 // Check that we can generate a route to a blinded path with the expected hops.
7329 let (secp_ctx, network, _, _, logger) = build_graph();
7330 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7331 let network_graph = network.read_only();
7333 let scorer = ln_test_utils::TestScorer::new();
7334 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7335 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7337 let mut blinded_path = BlindedPath {
7338 introduction_node_id: nodes[2],
7339 blinding_point: ln_test_utils::pubkey(42),
7340 blinded_hops: Vec::with_capacity(num_blinded_hops),
7342 for i in 0..num_blinded_hops {
7343 blinded_path.blinded_hops.push(
7344 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7347 let blinded_payinfo = BlindedPayInfo {
7349 fee_proportional_millionths: 500,
7350 htlc_minimum_msat: 1000,
7351 htlc_maximum_msat: 100_000_000,
7352 cltv_expiry_delta: 15,
7353 features: BlindedHopFeatures::empty(),
7356 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7357 let route_params = RouteParameters::from_payment_params_and_value(
7358 payment_params, 1001);
7359 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7360 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7361 assert_eq!(route.paths.len(), 1);
7362 assert_eq!(route.paths[0].hops.len(), 2);
7364 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7365 assert_eq!(tail.hops, blinded_path.blinded_hops);
7366 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7367 assert_eq!(tail.final_value_msat, 1001);
7369 let final_hop = route.paths[0].hops.last().unwrap();
7370 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
7371 if tail.hops.len() > 1 {
7372 assert_eq!(final_hop.fee_msat,
7373 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7374 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7376 assert_eq!(final_hop.fee_msat, 0);
7377 assert_eq!(final_hop.cltv_expiry_delta, 0);
7382 fn blinded_path_routing_errors() {
7383 // Check that we can generate a route to a blinded path with the expected hops.
7384 let (secp_ctx, network, _, _, logger) = build_graph();
7385 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7386 let network_graph = network.read_only();
7388 let scorer = ln_test_utils::TestScorer::new();
7389 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7390 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7392 let mut invalid_blinded_path = BlindedPath {
7393 introduction_node_id: nodes[2],
7394 blinding_point: ln_test_utils::pubkey(42),
7396 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7399 let blinded_payinfo = BlindedPayInfo {
7401 fee_proportional_millionths: 500,
7402 htlc_minimum_msat: 1000,
7403 htlc_maximum_msat: 100_000_000,
7404 cltv_expiry_delta: 15,
7405 features: BlindedHopFeatures::empty(),
7408 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7409 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7410 let payment_params = PaymentParameters::blinded(vec![
7411 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7412 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7413 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7414 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7415 &scorer, &Default::default(), &random_seed_bytes)
7417 Err(LightningError { err, .. }) => {
7418 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7420 _ => panic!("Expected error")
7423 invalid_blinded_path.introduction_node_id = our_id;
7424 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7425 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7426 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7427 &Default::default(), &random_seed_bytes)
7429 Err(LightningError { err, .. }) => {
7430 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7432 _ => panic!("Expected error")
7435 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7436 invalid_blinded_path.blinded_hops.clear();
7437 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7438 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7439 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7440 &Default::default(), &random_seed_bytes)
7442 Err(LightningError { err, .. }) => {
7443 assert_eq!(err, "0-hop blinded path provided");
7445 _ => panic!("Expected error")
7450 fn matching_intro_node_paths_provided() {
7451 // Check that if multiple blinded paths with the same intro node are provided in payment
7452 // parameters, we'll return the correct paths in the resulting MPP route.
7453 let (secp_ctx, network, _, _, logger) = build_graph();
7454 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7455 let network_graph = network.read_only();
7457 let scorer = ln_test_utils::TestScorer::new();
7458 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7459 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7460 let config = UserConfig::default();
7462 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7463 let blinded_path_1 = BlindedPath {
7464 introduction_node_id: nodes[2],
7465 blinding_point: ln_test_utils::pubkey(42),
7467 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7468 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7471 let blinded_payinfo_1 = BlindedPayInfo {
7473 fee_proportional_millionths: 0,
7474 htlc_minimum_msat: 0,
7475 htlc_maximum_msat: 30_000,
7476 cltv_expiry_delta: 0,
7477 features: BlindedHopFeatures::empty(),
7480 let mut blinded_path_2 = blinded_path_1.clone();
7481 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7482 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7483 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7485 let blinded_hints = vec![
7486 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7487 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7489 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7490 .with_bolt12_features(bolt12_features).unwrap();
7492 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7493 route_params.max_total_routing_fee_msat = Some(100_000);
7494 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7495 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7496 assert_eq!(route.paths.len(), 2);
7497 let mut total_amount_paid_msat = 0;
7498 for path in route.paths.into_iter() {
7499 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7500 if let Some(bt) = &path.blinded_tail {
7501 assert_eq!(bt.blinding_point,
7502 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7503 .map(|(_, bp)| bp.blinding_point).unwrap());
7504 } else { panic!(); }
7505 total_amount_paid_msat += path.final_value_msat();
7507 assert_eq!(total_amount_paid_msat, 100_000);
7511 fn direct_to_intro_node() {
7512 // This previously caused a debug panic in the router when asserting
7513 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7514 // direct channels we failed to account for the fee charged for use of the blinded path.
7517 // node0 -1(1)2 - node1
7518 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7519 // doesn't account for the blinded path fee.
7521 let secp_ctx = Secp256k1::new();
7522 let logger = Arc::new(ln_test_utils::TestLogger::new());
7523 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7524 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7525 let scorer = ln_test_utils::TestScorer::new();
7526 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7527 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7529 let amt_msat = 10_000_000;
7530 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7531 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7532 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7533 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7534 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7535 short_channel_id: 1,
7538 cltv_expiry_delta: 42,
7539 htlc_minimum_msat: 1_000,
7540 htlc_maximum_msat: 10_000_000,
7542 fee_proportional_millionths: 0,
7543 excess_data: Vec::new()
7545 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7546 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7547 short_channel_id: 1,
7550 cltv_expiry_delta: 42,
7551 htlc_minimum_msat: 1_000,
7552 htlc_maximum_msat: 10_000_000,
7554 fee_proportional_millionths: 0,
7555 excess_data: Vec::new()
7557 let first_hops = vec![
7558 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7560 let blinded_path = BlindedPath {
7561 introduction_node_id: nodes[1],
7562 blinding_point: ln_test_utils::pubkey(42),
7564 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7565 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7568 let blinded_payinfo = BlindedPayInfo {
7569 fee_base_msat: 1000,
7570 fee_proportional_millionths: 0,
7571 htlc_minimum_msat: 1000,
7572 htlc_maximum_msat: MAX_VALUE_MSAT,
7573 cltv_expiry_delta: 0,
7574 features: BlindedHopFeatures::empty(),
7576 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7578 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7580 let netgraph = network_graph.read_only();
7581 let route_params = RouteParameters::from_payment_params_and_value(
7582 payment_params.clone(), amt_msat);
7583 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7584 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7585 &Default::default(), &random_seed_bytes) {
7586 assert_eq!(err, "Failed to find a path to the given destination");
7587 } else { panic!("Expected error") }
7589 // Sending an exact amount accounting for the blinded path fee works.
7590 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7591 let route_params = RouteParameters::from_payment_params_and_value(
7592 payment_params, amt_minus_blinded_path_fee);
7593 let route = get_route(&nodes[0], &route_params, &netgraph,
7594 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7595 &Default::default(), &random_seed_bytes).unwrap();
7596 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7597 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7601 fn direct_to_matching_intro_nodes() {
7602 // This previously caused us to enter `unreachable` code in the following situation:
7603 // 1. We add a route candidate for intro_node contributing a high amount
7604 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7605 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7606 // amount, and update our route candidate for intro_node for the lower amount
7607 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7608 // lower contribution amount, but fail (this was previously caused by failure to account for
7609 // blinded path fees when adding first_hop<>intro_node candidates)
7610 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7611 // candidate still thinks its path is contributing the original higher amount. This caused us
7612 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7614 let secp_ctx = Secp256k1::new();
7615 let logger = Arc::new(ln_test_utils::TestLogger::new());
7616 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7617 let scorer = ln_test_utils::TestScorer::new();
7618 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7619 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7620 let config = UserConfig::default();
7622 // Values are taken from the fuzz input that uncovered this panic.
7623 let amt_msat = 21_7020_5185_1403_2640;
7624 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7625 let first_hops = vec![
7626 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7627 18446744073709551615)];
7629 let blinded_path = BlindedPath {
7630 introduction_node_id: nodes[1],
7631 blinding_point: ln_test_utils::pubkey(42),
7633 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7634 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7637 let blinded_payinfo = BlindedPayInfo {
7638 fee_base_msat: 5046_2720,
7639 fee_proportional_millionths: 0,
7640 htlc_minimum_msat: 4503_5996_2737_0496,
7641 htlc_maximum_msat: 45_0359_9627_3704_9600,
7642 cltv_expiry_delta: 0,
7643 features: BlindedHopFeatures::empty(),
7645 let mut blinded_hints = vec![
7646 (blinded_payinfo.clone(), blinded_path.clone()),
7647 (blinded_payinfo.clone(), blinded_path.clone()),
7649 blinded_hints[1].0.fee_base_msat = 419_4304;
7650 blinded_hints[1].0.fee_proportional_millionths = 257;
7651 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7652 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7653 blinded_hints[1].0.cltv_expiry_delta = 0;
7655 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7656 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7657 .with_bolt12_features(bolt12_features).unwrap();
7659 let netgraph = network_graph.read_only();
7660 let route_params = RouteParameters::from_payment_params_and_value(
7661 payment_params, amt_msat);
7662 let route = get_route(&nodes[0], &route_params, &netgraph,
7663 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7664 &Default::default(), &random_seed_bytes).unwrap();
7665 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7666 assert_eq!(route.get_total_amount(), amt_msat);
7670 fn we_are_intro_node_candidate_hops() {
7671 // This previously led to a panic in the router because we'd generate a Path with only a
7672 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7673 // where the origin node is the intro node. We now fully disallow considering candidate hops
7674 // where the origin node is the intro node.
7675 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7676 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7677 let scorer = ln_test_utils::TestScorer::new();
7678 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7679 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7680 let config = UserConfig::default();
7682 // Values are taken from the fuzz input that uncovered this panic.
7683 let amt_msat = 21_7020_5185_1423_0019;
7685 let blinded_path = BlindedPath {
7686 introduction_node_id: our_id,
7687 blinding_point: ln_test_utils::pubkey(42),
7689 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7690 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7693 let blinded_payinfo = BlindedPayInfo {
7694 fee_base_msat: 5052_9027,
7695 fee_proportional_millionths: 0,
7696 htlc_minimum_msat: 21_7020_5185_1423_0019,
7697 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7698 cltv_expiry_delta: 0,
7699 features: BlindedHopFeatures::empty(),
7701 let mut blinded_hints = vec![
7702 (blinded_payinfo.clone(), blinded_path.clone()),
7703 (blinded_payinfo.clone(), blinded_path.clone()),
7705 blinded_hints[1].1.introduction_node_id = nodes[6];
7707 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7708 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7709 .with_bolt12_features(bolt12_features.clone()).unwrap();
7711 let netgraph = network_graph.read_only();
7712 let route_params = RouteParameters::from_payment_params_and_value(
7713 payment_params, amt_msat);
7714 if let Err(LightningError { err, .. }) = get_route(
7715 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7717 assert_eq!(err, "Failed to find a path to the given destination");
7722 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7723 // This previously led to a debug panic in the router because we'd find an invalid Path with
7724 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7725 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7726 // the payment, when it was intended to only include the final value of the payment.
7727 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7728 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7729 let scorer = ln_test_utils::TestScorer::new();
7730 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7731 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7732 let config = UserConfig::default();
7734 // Values are taken from the fuzz input that uncovered this panic.
7735 let amt_msat = 21_7020_5185_1423_0019;
7737 let blinded_path = BlindedPath {
7738 introduction_node_id: our_id,
7739 blinding_point: ln_test_utils::pubkey(42),
7741 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7742 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7745 let blinded_payinfo = BlindedPayInfo {
7746 fee_base_msat: 10_4425_1395,
7747 fee_proportional_millionths: 0,
7748 htlc_minimum_msat: 21_7301_9934_9094_0931,
7749 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7750 cltv_expiry_delta: 0,
7751 features: BlindedHopFeatures::empty(),
7753 let mut blinded_hints = vec![
7754 (blinded_payinfo.clone(), blinded_path.clone()),
7755 (blinded_payinfo.clone(), blinded_path.clone()),
7756 (blinded_payinfo.clone(), blinded_path.clone()),
7758 blinded_hints[1].0.fee_base_msat = 5052_9027;
7759 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7760 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7762 blinded_hints[2].1.introduction_node_id = nodes[6];
7764 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7765 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7766 .with_bolt12_features(bolt12_features.clone()).unwrap();
7768 let netgraph = network_graph.read_only();
7769 let route_params = RouteParameters::from_payment_params_and_value(
7770 payment_params, amt_msat);
7771 if let Err(LightningError { err, .. }) = get_route(
7772 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7774 assert_eq!(err, "Failed to find a path to the given destination");
7779 fn min_htlc_overpay_violates_max_htlc() {
7780 do_min_htlc_overpay_violates_max_htlc(true);
7781 do_min_htlc_overpay_violates_max_htlc(false);
7783 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7784 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7785 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7786 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7787 // that the used liquidity for a hop was less than its available liquidity limit.
7788 let secp_ctx = Secp256k1::new();
7789 let logger = Arc::new(ln_test_utils::TestLogger::new());
7790 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7791 let scorer = ln_test_utils::TestScorer::new();
7792 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7793 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7794 let config = UserConfig::default();
7796 // Values are taken from the fuzz input that uncovered this panic.
7797 let amt_msat = 7_4009_8048;
7798 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7799 let first_hop_outbound_capacity = 2_7345_2000;
7800 let first_hops = vec![get_channel_details(
7801 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7802 first_hop_outbound_capacity
7805 let base_fee = 1_6778_3453;
7806 let htlc_min = 2_5165_8240;
7807 let payment_params = if blinded_payee {
7808 let blinded_path = BlindedPath {
7809 introduction_node_id: nodes[0],
7810 blinding_point: ln_test_utils::pubkey(42),
7812 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7813 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7816 let blinded_payinfo = BlindedPayInfo {
7817 fee_base_msat: base_fee,
7818 fee_proportional_millionths: 0,
7819 htlc_minimum_msat: htlc_min,
7820 htlc_maximum_msat: htlc_min * 1000,
7821 cltv_expiry_delta: 0,
7822 features: BlindedHopFeatures::empty(),
7824 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7825 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7826 .with_bolt12_features(bolt12_features.clone()).unwrap()
7828 let route_hint = RouteHint(vec![RouteHintHop {
7829 src_node_id: nodes[0],
7830 short_channel_id: 42,
7832 base_msat: base_fee,
7833 proportional_millionths: 0,
7835 cltv_expiry_delta: 10,
7836 htlc_minimum_msat: Some(htlc_min),
7837 htlc_maximum_msat: None,
7840 PaymentParameters::from_node_id(nodes[1], 42)
7841 .with_route_hints(vec![route_hint]).unwrap()
7842 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7845 let netgraph = network_graph.read_only();
7846 let route_params = RouteParameters::from_payment_params_and_value(
7847 payment_params, amt_msat);
7848 if let Err(LightningError { err, .. }) = get_route(
7849 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7850 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7852 assert_eq!(err, "Failed to find a path to the given destination");
7857 fn previously_used_liquidity_violates_max_htlc() {
7858 do_previously_used_liquidity_violates_max_htlc(true);
7859 do_previously_used_liquidity_violates_max_htlc(false);
7862 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7863 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7864 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7865 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7866 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7867 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7868 let secp_ctx = Secp256k1::new();
7869 let logger = Arc::new(ln_test_utils::TestLogger::new());
7870 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7871 let scorer = ln_test_utils::TestScorer::new();
7872 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7873 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7874 let config = UserConfig::default();
7876 // Values are taken from the fuzz input that uncovered this panic.
7877 let amt_msat = 52_4288;
7878 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7879 let first_hops = vec![get_channel_details(
7880 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7881 ), get_channel_details(
7882 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7885 let base_fees = [0, 425_9840, 0, 0];
7886 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7887 let payment_params = if blinded_payee {
7888 let blinded_path = BlindedPath {
7889 introduction_node_id: nodes[0],
7890 blinding_point: ln_test_utils::pubkey(42),
7892 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7893 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7896 let mut blinded_hints = Vec::new();
7897 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7898 blinded_hints.push((BlindedPayInfo {
7899 fee_base_msat: *base_fee,
7900 fee_proportional_millionths: 0,
7901 htlc_minimum_msat: *htlc_min,
7902 htlc_maximum_msat: htlc_min * 100,
7903 cltv_expiry_delta: 10,
7904 features: BlindedHopFeatures::empty(),
7905 }, blinded_path.clone()));
7907 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7908 PaymentParameters::blinded(blinded_hints.clone())
7909 .with_bolt12_features(bolt12_features.clone()).unwrap()
7911 let mut route_hints = Vec::new();
7912 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7913 route_hints.push(RouteHint(vec![RouteHintHop {
7914 src_node_id: nodes[0],
7915 short_channel_id: 42 + idx as u64,
7917 base_msat: *base_fee,
7918 proportional_millionths: 0,
7920 cltv_expiry_delta: 10,
7921 htlc_minimum_msat: Some(*htlc_min),
7922 htlc_maximum_msat: Some(htlc_min * 100),
7925 PaymentParameters::from_node_id(nodes[1], 42)
7926 .with_route_hints(route_hints).unwrap()
7927 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7930 let netgraph = network_graph.read_only();
7931 let route_params = RouteParameters::from_payment_params_and_value(
7932 payment_params, amt_msat);
7934 let route = get_route(
7935 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7936 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7938 assert_eq!(route.paths.len(), 1);
7939 assert_eq!(route.get_total_amount(), amt_msat);
7943 fn candidate_path_min() {
7944 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7945 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7946 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7947 // would add a connecting first_hop node that did not have enough contribution amount, leading
7948 // to a debug panic upon invalid path construction.
7949 let secp_ctx = Secp256k1::new();
7950 let logger = Arc::new(ln_test_utils::TestLogger::new());
7951 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7952 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7953 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7954 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7955 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7956 let config = UserConfig::default();
7958 // Values are taken from the fuzz input that uncovered this panic.
7959 let amt_msat = 7_4009_8048;
7960 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7961 let first_hops = vec![get_channel_details(
7962 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7965 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7966 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7967 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7968 short_channel_id: 6,
7971 cltv_expiry_delta: (6 << 4) | 0,
7972 htlc_minimum_msat: 0,
7973 htlc_maximum_msat: MAX_VALUE_MSAT,
7975 fee_proportional_millionths: 0,
7976 excess_data: Vec::new()
7978 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7980 let htlc_min = 2_5165_8240;
7981 let blinded_hints = vec![
7983 fee_base_msat: 1_6778_3453,
7984 fee_proportional_millionths: 0,
7985 htlc_minimum_msat: htlc_min,
7986 htlc_maximum_msat: htlc_min * 100,
7987 cltv_expiry_delta: 10,
7988 features: BlindedHopFeatures::empty(),
7990 introduction_node_id: nodes[0],
7991 blinding_point: ln_test_utils::pubkey(42),
7993 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7994 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7998 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7999 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
8000 .with_bolt12_features(bolt12_features.clone()).unwrap();
8001 let route_params = RouteParameters::from_payment_params_and_value(
8002 payment_params, amt_msat);
8003 let netgraph = network_graph.read_only();
8005 if let Err(LightningError { err, .. }) = get_route(
8006 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8007 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8010 assert_eq!(err, "Failed to find a path to the given destination");
8015 fn path_contribution_includes_min_htlc_overpay() {
8016 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
8017 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
8018 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
8019 // selection, both tested here.
8020 let secp_ctx = Secp256k1::new();
8021 let logger = Arc::new(ln_test_utils::TestLogger::new());
8022 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8023 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
8024 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8025 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8026 let config = UserConfig::default();
8028 // Values are taken from the fuzz input that uncovered this panic.
8029 let amt_msat = 562_0000;
8030 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8031 let first_hops = vec![
8032 get_channel_details(
8033 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
8037 let htlc_mins = [49_0000, 1125_0000];
8038 let payment_params = {
8039 let blinded_path = BlindedPath {
8040 introduction_node_id: nodes[0],
8041 blinding_point: ln_test_utils::pubkey(42),
8043 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8044 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8047 let mut blinded_hints = Vec::new();
8048 for htlc_min in htlc_mins.iter() {
8049 blinded_hints.push((BlindedPayInfo {
8051 fee_proportional_millionths: 0,
8052 htlc_minimum_msat: *htlc_min,
8053 htlc_maximum_msat: *htlc_min * 100,
8054 cltv_expiry_delta: 10,
8055 features: BlindedHopFeatures::empty(),
8056 }, blinded_path.clone()));
8058 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8059 PaymentParameters::blinded(blinded_hints.clone())
8060 .with_bolt12_features(bolt12_features.clone()).unwrap()
8063 let netgraph = network_graph.read_only();
8064 let route_params = RouteParameters::from_payment_params_and_value(
8065 payment_params, amt_msat);
8066 let route = get_route(
8067 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8068 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8071 assert_eq!(route.paths.len(), 1);
8072 assert_eq!(route.get_total_amount(), amt_msat);
8076 fn first_hop_preferred_over_hint() {
8077 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
8078 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
8079 let secp_ctx = Secp256k1::new();
8080 let logger = Arc::new(ln_test_utils::TestLogger::new());
8081 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8082 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
8083 let scorer = ln_test_utils::TestScorer::new();
8084 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8085 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8086 let config = UserConfig::default();
8088 let amt_msat = 1_000_000;
8089 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
8091 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
8092 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
8093 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
8094 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8095 short_channel_id: 1,
8098 cltv_expiry_delta: 42,
8099 htlc_minimum_msat: 1_000,
8100 htlc_maximum_msat: 10_000_000,
8102 fee_proportional_millionths: 0,
8103 excess_data: Vec::new()
8105 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8106 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8107 short_channel_id: 1,
8110 cltv_expiry_delta: 42,
8111 htlc_minimum_msat: 1_000,
8112 htlc_maximum_msat: 10_000_000,
8114 fee_proportional_millionths: 0,
8115 excess_data: Vec::new()
8118 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
8119 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
8120 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8121 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8122 short_channel_id: 2,
8125 cltv_expiry_delta: 42,
8126 htlc_minimum_msat: 1_000,
8127 htlc_maximum_msat: 10_000_000,
8129 fee_proportional_millionths: 0,
8130 excess_data: Vec::new()
8132 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
8133 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8134 short_channel_id: 2,
8137 cltv_expiry_delta: 42,
8138 htlc_minimum_msat: 1_000,
8139 htlc_maximum_msat: 10_000_000,
8141 fee_proportional_millionths: 0,
8142 excess_data: Vec::new()
8145 let dest_node_id = nodes[2];
8147 let route_hint = RouteHint(vec![RouteHintHop {
8148 src_node_id: our_node_id,
8149 short_channel_id: 44,
8152 proportional_millionths: 0,
8154 cltv_expiry_delta: 10,
8155 htlc_minimum_msat: None,
8156 htlc_maximum_msat: Some(5_000_000),
8159 src_node_id: nodes[0],
8160 short_channel_id: 45,
8163 proportional_millionths: 0,
8165 cltv_expiry_delta: 10,
8166 htlc_minimum_msat: None,
8167 htlc_maximum_msat: None,
8170 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8171 .with_route_hints(vec![route_hint]).unwrap()
8172 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8173 let route_params = RouteParameters::from_payment_params_and_value(
8174 payment_params, amt_msat);
8176 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8178 let first_hop = get_channel_details(Some(1), nodes[0],
8179 channelmanager::provided_init_features(&config), 999_999);
8180 let first_hops = vec![first_hop];
8182 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8183 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8184 &Default::default(), &random_seed_bytes).unwrap();
8185 assert_eq!(route.paths.len(), 1);
8186 assert_eq!(route.get_total_amount(), amt_msat);
8187 assert_eq!(route.paths[0].hops.len(), 2);
8188 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8189 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8190 assert_eq!(route.get_total_fees(), 123);
8192 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8193 // for a first hop channel.
8194 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8195 first_hop.outbound_scid_alias = Some(44);
8196 let first_hops = vec![first_hop];
8198 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8199 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8200 &Default::default(), &random_seed_bytes);
8201 assert!(route_res.is_err());
8203 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8204 // use the cheaper second hop of the route hint.
8205 let mut first_hop = get_channel_details(Some(1), nodes[0],
8206 channelmanager::provided_init_features(&config), 10_000_000);
8207 first_hop.outbound_scid_alias = Some(44);
8208 let first_hops = vec![first_hop];
8210 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8211 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8212 &Default::default(), &random_seed_bytes).unwrap();
8213 assert_eq!(route.paths.len(), 1);
8214 assert_eq!(route.get_total_amount(), amt_msat);
8215 assert_eq!(route.paths[0].hops.len(), 2);
8216 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8217 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8218 assert_eq!(route.get_total_fees(), 123);
8222 fn allow_us_being_first_hint() {
8223 // Check that we consider a route hint even if we are the src of the first hop.
8224 let secp_ctx = Secp256k1::new();
8225 let logger = Arc::new(ln_test_utils::TestLogger::new());
8226 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8227 let scorer = ln_test_utils::TestScorer::new();
8228 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8229 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8230 let config = UserConfig::default();
8232 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8234 let amt_msat = 1_000_000;
8235 let dest_node_id = nodes[1];
8237 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8238 let first_hops = vec![first_hop];
8240 let route_hint = RouteHint(vec![RouteHintHop {
8241 src_node_id: our_node_id,
8242 short_channel_id: 44,
8245 proportional_millionths: 0,
8247 cltv_expiry_delta: 10,
8248 htlc_minimum_msat: None,
8249 htlc_maximum_msat: None,
8252 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8253 .with_route_hints(vec![route_hint]).unwrap()
8254 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8256 let route_params = RouteParameters::from_payment_params_and_value(
8257 payment_params, amt_msat);
8260 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8261 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8262 &Default::default(), &random_seed_bytes).unwrap();
8264 assert_eq!(route.paths.len(), 1);
8265 assert_eq!(route.get_total_amount(), amt_msat);
8266 assert_eq!(route.get_total_fees(), 0);
8267 assert_eq!(route.paths[0].hops.len(), 1);
8269 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8273 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
8274 pub(crate) mod bench_utils {
8277 use std::time::Duration;
8279 use bitcoin::hashes::Hash;
8280 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
8282 use crate::chain::transaction::OutPoint;
8283 use crate::routing::scoring::ScoreUpdate;
8284 use crate::sign::{EntropySource, KeysManager};
8285 use crate::ln::ChannelId;
8286 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
8287 use crate::ln::features::Bolt11InvoiceFeatures;
8288 use crate::routing::gossip::NetworkGraph;
8289 use crate::util::config::UserConfig;
8290 use crate::util::ser::ReadableArgs;
8291 use crate::util::test_utils::TestLogger;
8293 /// Tries to open a network graph file, or panics with a URL to fetch it.
8294 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
8295 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
8296 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
8297 .or_else(|_| { // Fall back to guessing based on the binary location
8298 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8299 let mut path = std::env::current_exe().unwrap();
8300 path.pop(); // lightning-...
8302 path.pop(); // debug
8303 path.pop(); // target
8304 path.push("lightning");
8305 path.push("net_graph-2023-01-18.bin");
8308 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8309 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8310 let mut path = std::env::current_exe().unwrap();
8311 path.pop(); // bench...
8313 path.pop(); // debug
8314 path.pop(); // target
8315 path.pop(); // bench
8316 path.push("lightning");
8317 path.push("net_graph-2023-01-18.bin");
8320 .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");
8321 #[cfg(require_route_graph_test)]
8322 return Ok(res.unwrap());
8323 #[cfg(not(require_route_graph_test))]
8327 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
8328 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
8331 pub(crate) fn payer_pubkey() -> PublicKey {
8332 let secp_ctx = Secp256k1::new();
8333 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8337 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8339 channel_id: ChannelId::new_zero(),
8340 counterparty: ChannelCounterparty {
8341 features: channelmanager::provided_init_features(&UserConfig::default()),
8343 unspendable_punishment_reserve: 0,
8344 forwarding_info: None,
8345 outbound_htlc_minimum_msat: None,
8346 outbound_htlc_maximum_msat: None,
8348 funding_txo: Some(OutPoint {
8349 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8352 short_channel_id: Some(1),
8353 inbound_scid_alias: None,
8354 outbound_scid_alias: None,
8355 channel_value_satoshis: 10_000_000_000,
8357 balance_msat: 10_000_000_000,
8358 outbound_capacity_msat: 10_000_000_000,
8359 next_outbound_htlc_minimum_msat: 0,
8360 next_outbound_htlc_limit_msat: 10_000_000_000,
8361 inbound_capacity_msat: 0,
8362 unspendable_punishment_reserve: None,
8363 confirmations_required: None,
8364 confirmations: None,
8365 force_close_spend_delay: None,
8367 is_channel_ready: true,
8370 inbound_htlc_minimum_msat: None,
8371 inbound_htlc_maximum_msat: None,
8373 feerate_sat_per_1000_weight: None,
8374 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
8378 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8379 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8380 starting_amount: u64, route_count: usize,
8381 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8382 let payer = payer_pubkey();
8383 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8384 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8386 let nodes = graph.read_only().nodes().clone();
8387 let mut route_endpoints = Vec::new();
8388 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
8389 // with some routes we picked being un-routable.
8390 for _ in 0..route_count * 3 / 2 {
8392 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8393 let src = PublicKey::from_slice(nodes.unordered_keys()
8394 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8395 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8396 let dst = PublicKey::from_slice(nodes.unordered_keys()
8397 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8398 let params = PaymentParameters::from_node_id(dst, 42)
8399 .with_bolt11_features(features.clone()).unwrap();
8400 let first_hop = first_hop(src);
8401 let amt_msat = starting_amount + seed % 1_000_000;
8402 let route_params = RouteParameters::from_payment_params_and_value(
8403 params.clone(), amt_msat);
8405 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8406 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8408 // ...and seed the scorer with success and failure data...
8409 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8410 let mut score_amt = seed % 1_000_000_000;
8412 // Generate fail/success paths for a wider range of potential amounts with
8413 // MPP enabled to give us a chance to apply penalties for more potential
8415 let mpp_features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
8416 let params = PaymentParameters::from_node_id(dst, 42)
8417 .with_bolt11_features(mpp_features).unwrap();
8418 let route_params = RouteParameters::from_payment_params_and_value(
8419 params.clone(), score_amt);
8420 let route_res = get_route(&payer, &route_params, &graph.read_only(),
8421 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
8422 &random_seed_bytes);
8423 if let Ok(route) = route_res {
8424 for path in route.paths {
8425 if seed & 0x80 == 0 {
8426 scorer.payment_path_successful(&path, Duration::ZERO);
8428 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
8429 scorer.payment_path_failed(&path, short_channel_id, Duration::ZERO);
8431 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8435 // If we couldn't find a path with a higer amount, reduce and try again.
8439 route_endpoints.push((first_hop, params, amt_msat));
8445 // Because we've changed channel scores, it's possible we'll take different routes to the
8446 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
8447 // requires a too-high CLTV delta.
8448 route_endpoints.retain(|(first_hop, params, amt_msat)| {
8449 let route_params = RouteParameters::from_payment_params_and_value(
8450 params.clone(), *amt_msat);
8451 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8452 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
8454 route_endpoints.truncate(route_count);
8455 assert_eq!(route_endpoints.len(), route_count);
8463 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8464 use crate::sign::{EntropySource, KeysManager};
8465 use crate::ln::channelmanager;
8466 use crate::ln::features::Bolt11InvoiceFeatures;
8467 use crate::routing::gossip::NetworkGraph;
8468 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
8469 use crate::util::config::UserConfig;
8470 use crate::util::logger::{Logger, Record};
8471 use crate::util::test_utils::TestLogger;
8473 use criterion::Criterion;
8475 struct DummyLogger {}
8476 impl Logger for DummyLogger {
8477 fn log(&self, _record: Record) {}
8480 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8481 let logger = TestLogger::new();
8482 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8483 let scorer = FixedPenaltyScorer::with_penalty(0);
8484 generate_routes(bench, &network_graph, scorer, &Default::default(),
8485 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8488 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8489 let logger = TestLogger::new();
8490 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8491 let scorer = FixedPenaltyScorer::with_penalty(0);
8492 generate_routes(bench, &network_graph, scorer, &Default::default(),
8493 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8494 "generate_mpp_routes_with_zero_penalty_scorer");
8497 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8498 let logger = TestLogger::new();
8499 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8500 let params = ProbabilisticScoringFeeParameters::default();
8501 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8502 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8503 "generate_routes_with_probabilistic_scorer");
8506 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8507 let logger = TestLogger::new();
8508 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8509 let params = ProbabilisticScoringFeeParameters::default();
8510 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8511 generate_routes(bench, &network_graph, scorer, ¶ms,
8512 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8513 "generate_mpp_routes_with_probabilistic_scorer");
8516 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8517 let logger = TestLogger::new();
8518 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8519 let params = ProbabilisticScoringFeeParameters::default();
8520 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8521 generate_routes(bench, &network_graph, scorer, ¶ms,
8522 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8523 "generate_large_mpp_routes_with_probabilistic_scorer");
8526 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8527 let logger = TestLogger::new();
8528 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8529 let mut params = ProbabilisticScoringFeeParameters::default();
8530 params.linear_success_probability = false;
8531 let scorer = ProbabilisticScorer::new(
8532 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8533 generate_routes(bench, &network_graph, scorer, ¶ms,
8534 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8535 "generate_routes_with_nonlinear_probabilistic_scorer");
8538 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8539 let logger = TestLogger::new();
8540 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8541 let mut params = ProbabilisticScoringFeeParameters::default();
8542 params.linear_success_probability = false;
8543 let scorer = ProbabilisticScorer::new(
8544 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8545 generate_routes(bench, &network_graph, scorer, ¶ms,
8546 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8547 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8550 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8551 let logger = TestLogger::new();
8552 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8553 let mut params = ProbabilisticScoringFeeParameters::default();
8554 params.linear_success_probability = false;
8555 let scorer = ProbabilisticScorer::new(
8556 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8557 generate_routes(bench, &network_graph, scorer, ¶ms,
8558 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8559 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8562 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8563 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8564 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8565 bench_name: &'static str,
8567 let payer = bench_utils::payer_pubkey();
8568 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8569 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8571 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8572 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8574 // ...then benchmark finding paths between the nodes we learned.
8576 bench.bench_function(bench_name, |b| b.iter(|| {
8577 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8578 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8579 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8580 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());