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;
13 use bitcoin::hashes::Hash;
14 use bitcoin::hashes::sha256::Hash as Sha256;
16 use crate::blinded_path::{BlindedHop, BlindedPath};
17 use crate::ln::PaymentHash;
18 use crate::ln::channelmanager::{ChannelDetails, PaymentId};
19 use crate::ln::features::{Bolt12InvoiceFeatures, ChannelFeatures, InvoiceFeatures, NodeFeatures};
20 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
21 use crate::offers::invoice::BlindedPayInfo;
22 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
23 use crate::routing::scoring::{ChannelUsage, LockableScore, Score};
24 use crate::util::ser::{Writeable, Readable, ReadableArgs, Writer};
25 use crate::util::logger::{Level, Logger};
26 use crate::util::chacha20::ChaCha20;
29 use crate::prelude::*;
30 use crate::sync::{Mutex, MutexGuard};
31 use alloc::collections::BinaryHeap;
35 /// A [`Router`] implemented using [`find_route`].
36 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: Score<ScoreParams = SP>> where
38 S::Target: for <'a> LockableScore<'a, Locked = MutexGuard<'a, Sc>>,
42 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: Score<ScoreParams = SP>> DefaultRouter<G, L, S, SP, Sc> where
49 S::Target: for <'a> LockableScore<'a, Locked = MutexGuard<'a, Sc>>,
51 /// Creates a new router.
52 pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S, score_params: SP) -> Self {
53 let random_seed_bytes = Mutex::new(random_seed_bytes);
54 Self { network_graph, logger, random_seed_bytes, scorer, score_params }
58 impl< G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: Score<ScoreParams = SP>> Router for DefaultRouter<G, L, S, SP, Sc> where
60 S::Target: for <'a> LockableScore<'a, Locked = MutexGuard<'a, Sc>>,
65 params: &RouteParameters,
66 first_hops: Option<&[&ChannelDetails]>,
67 inflight_htlcs: &InFlightHtlcs
68 ) -> Result<Route, LightningError> {
69 let random_seed_bytes = {
70 let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
71 *locked_random_seed_bytes = Sha256::hash(&*locked_random_seed_bytes).into_inner();
72 *locked_random_seed_bytes
75 payer, params, &self.network_graph, first_hops, &*self.logger,
76 &ScorerAccountingForInFlightHtlcs::new(self.scorer.lock(), inflight_htlcs),
83 /// A trait defining behavior for routing a payment.
85 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values.
87 &self, payer: &PublicKey, route_params: &RouteParameters,
88 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: &InFlightHtlcs
89 ) -> Result<Route, LightningError>;
90 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values. Includes
91 /// `PaymentHash` and `PaymentId` to be able to correlate the request with a specific payment.
92 fn find_route_with_id(
93 &self, payer: &PublicKey, route_params: &RouteParameters,
94 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: &InFlightHtlcs,
95 _payment_hash: PaymentHash, _payment_id: PaymentId
96 ) -> Result<Route, LightningError> {
97 self.find_route(payer, route_params, first_hops, inflight_htlcs)
101 /// [`Score`] implementation that factors in in-flight HTLC liquidity.
103 /// Useful for custom [`Router`] implementations to wrap their [`Score`] on-the-fly when calling
106 /// [`Score`]: crate::routing::scoring::Score
107 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Score> {
109 // Maps a channel's short channel id and its direction to the liquidity used up.
110 inflight_htlcs: &'a InFlightHtlcs,
113 impl<'a, S: Score> ScorerAccountingForInFlightHtlcs<'a, S> {
114 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
115 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
116 ScorerAccountingForInFlightHtlcs {
124 impl<'a, S: Score> Writeable for ScorerAccountingForInFlightHtlcs<'a, S> {
125 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
128 impl<'a, S: Score> Score for ScorerAccountingForInFlightHtlcs<'a, S> {
129 type ScoreParams = S::ScoreParams;
130 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
131 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
132 source, target, short_channel_id
134 let usage = ChannelUsage {
135 inflight_htlc_msat: usage.inflight_htlc_msat + used_liquidity,
139 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
141 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
145 fn payment_path_failed(&mut self, path: &Path, short_channel_id: u64) {
146 self.scorer.payment_path_failed(path, short_channel_id)
149 fn payment_path_successful(&mut self, path: &Path) {
150 self.scorer.payment_path_successful(path)
153 fn probe_failed(&mut self, path: &Path, short_channel_id: u64) {
154 self.scorer.probe_failed(path, short_channel_id)
157 fn probe_successful(&mut self, path: &Path) {
158 self.scorer.probe_successful(path)
162 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
163 /// in-use channel liquidity.
165 pub struct InFlightHtlcs(
166 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
167 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
168 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
170 HashMap<(u64, bool), u64>
174 /// Constructs an empty `InFlightHtlcs`.
175 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
177 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
178 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
179 if path.hops.is_empty() { return };
181 let mut cumulative_msat = 0;
182 if let Some(tail) = &path.blinded_tail {
183 cumulative_msat += tail.final_value_msat;
186 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
187 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
188 // the router excludes the payer node. In the following lines, the payer's information is
189 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
190 // in our sliding window of two.
191 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
192 .map(|hop| hop.pubkey)
193 .chain(core::iter::once(payer_node_id));
195 // Taking the reversed vector from above, we zip it with just the reversed hops list to
196 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
197 // the total amount sent.
198 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
199 cumulative_msat += next_hop.fee_msat;
201 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
202 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
203 .or_insert(cumulative_msat);
207 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
209 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
210 self.0.get(&(channel_scid, source < target)).map(|v| *v)
214 impl Writeable for InFlightHtlcs {
215 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
218 impl Readable for InFlightHtlcs {
219 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
220 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
221 Ok(Self(infight_map))
225 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
226 /// that leads to it.
227 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
228 pub struct RouteHop {
229 /// The node_id of the node at this hop.
230 pub pubkey: PublicKey,
231 /// The node_announcement features of the node at this hop. For the last hop, these may be
232 /// amended to match the features present in the invoice this node generated.
233 pub node_features: NodeFeatures,
234 /// The channel that should be used from the previous hop to reach this node.
235 pub short_channel_id: u64,
236 /// The channel_announcement features of the channel that should be used from the previous hop
237 /// to reach this node.
238 pub channel_features: ChannelFeatures,
239 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
240 /// If this is the last hop in [`Path::hops`]:
241 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
242 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
244 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
246 /// The CLTV delta added for this hop.
247 /// If this is the last hop in [`Path::hops`]:
248 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
249 /// * otherwise, this is the CLTV delta expected at the destination
251 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
252 pub cltv_expiry_delta: u32,
255 impl_writeable_tlv_based!(RouteHop, {
256 (0, pubkey, required),
257 (2, node_features, required),
258 (4, short_channel_id, required),
259 (6, channel_features, required),
260 (8, fee_msat, required),
261 (10, cltv_expiry_delta, required),
264 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
265 /// their BOLT12 [`Invoice`].
267 /// [`Invoice`]: crate::offers::invoice::Invoice
268 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
269 pub struct BlindedTail {
270 /// The hops of the [`BlindedPath`] provided by the recipient.
272 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
273 pub hops: Vec<BlindedHop>,
274 /// The blinding point of the [`BlindedPath`] provided by the recipient.
276 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
277 pub blinding_point: PublicKey,
278 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
279 /// inferring the destination. May be 0.
280 pub excess_final_cltv_expiry_delta: u32,
281 /// The total amount paid on this [`Path`], excluding the fees.
282 pub final_value_msat: u64,
285 impl_writeable_tlv_based!(BlindedTail, {
287 (2, blinding_point, required),
288 (4, excess_final_cltv_expiry_delta, required),
289 (6, final_value_msat, required),
292 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
293 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
294 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
296 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
297 pub hops: Vec<RouteHop>,
298 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
299 pub blinded_tail: Option<BlindedTail>,
303 /// Gets the fees for a given path, excluding any excess paid to the recipient.
304 pub fn fee_msat(&self) -> u64 {
305 match &self.blinded_tail {
306 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
308 // Do not count last hop of each path since that's the full value of the payment
309 self.hops.split_last().map_or(0,
310 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
315 /// Gets the total amount paid on this [`Path`], excluding the fees.
316 pub fn final_value_msat(&self) -> u64 {
317 match &self.blinded_tail {
318 Some(blinded_tail) => blinded_tail.final_value_msat,
319 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
323 /// Gets the final hop's CLTV expiry delta.
324 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
325 match &self.blinded_tail {
327 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
332 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
333 /// it can take multiple paths. Each path is composed of one or more hops through the network.
334 #[derive(Clone, Hash, PartialEq, Eq)]
336 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
337 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
339 pub paths: Vec<Path>,
340 /// The `payment_params` parameter passed to [`find_route`].
341 /// This is used by `ChannelManager` to track information which may be required for retries,
342 /// provided back to you via [`Event::PaymentPathFailed`].
344 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
345 pub payment_params: Option<PaymentParameters>,
349 /// Returns the total amount of fees paid on this [`Route`].
351 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
352 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
353 pub fn get_total_fees(&self) -> u64 {
354 self.paths.iter().map(|path| path.fee_msat()).sum()
357 /// Returns the total amount paid on this [`Route`], excluding the fees. Might be more than
358 /// requested if we had to reach htlc_minimum_msat.
359 pub fn get_total_amount(&self) -> u64 {
360 self.paths.iter().map(|path| path.final_value_msat()).sum()
364 const SERIALIZATION_VERSION: u8 = 1;
365 const MIN_SERIALIZATION_VERSION: u8 = 1;
367 impl Writeable for Route {
368 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
369 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
370 (self.paths.len() as u64).write(writer)?;
371 let mut blinded_tails = Vec::new();
372 for path in self.paths.iter() {
373 (path.hops.len() as u8).write(writer)?;
374 for (idx, hop) in path.hops.iter().enumerate() {
376 if let Some(blinded_tail) = &path.blinded_tail {
377 if blinded_tails.is_empty() {
378 blinded_tails = Vec::with_capacity(path.hops.len());
380 blinded_tails.push(None);
383 blinded_tails.push(Some(blinded_tail));
384 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
387 write_tlv_fields!(writer, {
388 (1, self.payment_params, option),
389 (2, blinded_tails, optional_vec),
395 impl Readable for Route {
396 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
397 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
398 let path_count: u64 = Readable::read(reader)?;
399 if path_count == 0 { return Err(DecodeError::InvalidValue); }
400 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
401 let mut min_final_cltv_expiry_delta = u32::max_value();
402 for _ in 0..path_count {
403 let hop_count: u8 = Readable::read(reader)?;
404 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
405 for _ in 0..hop_count {
406 hops.push(Readable::read(reader)?);
408 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
409 min_final_cltv_expiry_delta =
410 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
411 paths.push(Path { hops, blinded_tail: None });
413 _init_and_read_tlv_fields!(reader, {
414 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
415 (2, blinded_tails, optional_vec),
417 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
418 if blinded_tails.len() != 0 {
419 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
420 for (mut path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
421 path.blinded_tail = blinded_tail_opt;
424 Ok(Route { paths, payment_params })
428 /// Parameters needed to find a [`Route`].
430 /// Passed to [`find_route`] and [`build_route_from_hops`], but also provided in
431 /// [`Event::PaymentPathFailed`].
433 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
434 #[derive(Clone, Debug, PartialEq, Eq)]
435 pub struct RouteParameters {
436 /// The parameters of the failed payment path.
437 pub payment_params: PaymentParameters,
439 /// The amount in msats sent on the failed payment path.
440 pub final_value_msat: u64,
443 impl Writeable for RouteParameters {
444 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
445 write_tlv_fields!(writer, {
446 (0, self.payment_params, required),
447 (2, self.final_value_msat, required),
448 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
449 // `RouteParameters` directly. For compatibility, we write it here.
450 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
456 impl Readable for RouteParameters {
457 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
458 _init_and_read_tlv_fields!(reader, {
459 (0, payment_params, (required: ReadableArgs, 0)),
460 (2, final_value_msat, required),
461 (4, final_cltv_delta, option),
463 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
464 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
465 if final_cltv_expiry_delta == &0 {
466 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
471 final_value_msat: final_value_msat.0.unwrap(),
476 /// Maximum total CTLV difference we allow for a full payment path.
477 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
479 /// Maximum number of paths we allow an (MPP) payment to have.
480 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
481 // limits, but for now more than 10 paths likely carries too much one-path failure.
482 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
484 // The median hop CLTV expiry delta currently seen in the network.
485 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
487 // During routing, we only consider paths shorter than our maximum length estimate.
488 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
489 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
490 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
492 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
493 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
494 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
495 // (payment_secret and total_msat) = 93 bytes for the final hop.
496 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
497 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
498 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
500 /// Information used to route a payment.
501 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
502 pub struct PaymentParameters {
503 /// Information about the payee, such as their features and route hints for their channels.
506 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
507 pub expiry_time: Option<u64>,
509 /// The maximum total CLTV delta we accept for the route.
510 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
511 pub max_total_cltv_expiry_delta: u32,
513 /// The maximum number of paths that may be used by (MPP) payments.
514 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
515 pub max_path_count: u8,
517 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
518 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
519 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
520 /// increasing failure probability for those paths.
522 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
523 /// restriction have been found. While paths which meet this criteria will be searched for, it
524 /// is ultimately up to the scorer to select them over other paths.
526 /// A value of 0 will allow payments up to and including a channel's total announced usable
527 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
530 pub max_channel_saturation_power_of_half: u8,
532 /// A list of SCIDs which this payment was previously attempted over and which caused the
533 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
535 pub previously_failed_channels: Vec<u64>,
538 impl Writeable for PaymentParameters {
539 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
540 let mut clear_hints = &vec![];
541 let mut blinded_hints = &vec![];
543 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
544 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
546 write_tlv_fields!(writer, {
547 (0, self.payee.node_id(), option),
548 (1, self.max_total_cltv_expiry_delta, required),
549 (2, self.payee.features(), option),
550 (3, self.max_path_count, required),
551 (4, *clear_hints, vec_type),
552 (5, self.max_channel_saturation_power_of_half, required),
553 (6, self.expiry_time, option),
554 (7, self.previously_failed_channels, vec_type),
555 (8, *blinded_hints, optional_vec),
556 (9, self.payee.final_cltv_expiry_delta(), option),
562 impl ReadableArgs<u32> for PaymentParameters {
563 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
564 _init_and_read_tlv_fields!(reader, {
565 (0, payee_pubkey, option),
566 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
567 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
568 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
569 (4, route_hints, vec_type),
570 (5, max_channel_saturation_power_of_half, (default_value, 2)),
571 (6, expiry_time, option),
572 (7, previously_failed_channels, vec_type),
573 (8, blinded_route_hints, optional_vec),
574 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
576 let clear_route_hints = route_hints.unwrap_or(vec![]);
577 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
578 let payee = if blinded_route_hints.len() != 0 {
579 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
581 route_hints: blinded_route_hints,
582 features: features.and_then(|f: Features| f.bolt12()),
586 route_hints: clear_route_hints,
587 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
588 features: features.and_then(|f| f.bolt11()),
589 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
593 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
594 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
596 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
598 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
604 impl PaymentParameters {
605 /// Creates a payee with the node id of the given `pubkey`.
607 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
609 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
611 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
613 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
614 max_path_count: DEFAULT_MAX_PATH_COUNT,
615 max_channel_saturation_power_of_half: 2,
616 previously_failed_channels: Vec::new(),
620 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
622 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
625 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
626 /// whether your router will be allowed to find a multi-part route for this payment. If you
627 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
628 /// [`RecipientOnionFields::secret_only`].
630 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
631 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
632 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
633 .with_bolt11_features(InvoiceFeatures::for_keysend(allow_mpp))
634 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
637 /// Includes the payee's features. Errors if the parameters were initialized with blinded payment
640 /// This is not exported to bindings users since bindings don't support move semantics
641 pub fn with_bolt11_features(self, features: InvoiceFeatures) -> Result<Self, ()> {
643 Payee::Blinded { .. } => Err(()),
644 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
646 payee: Payee::Clear {
647 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
653 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
654 /// blinded payment paths.
656 /// This is not exported to bindings users since bindings don't support move semantics
657 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
659 Payee::Blinded { .. } => Err(()),
660 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
662 payee: Payee::Clear {
663 route_hints, node_id, features, final_cltv_expiry_delta,
669 /// Includes a payment expiration in seconds relative to the UNIX epoch.
671 /// This is not exported to bindings users since bindings don't support move semantics
672 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
673 Self { expiry_time: Some(expiry_time), ..self }
676 /// Includes a limit for the total CLTV expiry delta which is considered during routing
678 /// This is not exported to bindings users since bindings don't support move semantics
679 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
680 Self { max_total_cltv_expiry_delta, ..self }
683 /// Includes a limit for the maximum number of payment paths that may be used.
685 /// This is not exported to bindings users since bindings don't support move semantics
686 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
687 Self { max_path_count, ..self }
690 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
691 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
693 /// This is not exported to bindings users since bindings don't support move semantics
694 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
695 Self { max_channel_saturation_power_of_half, ..self }
699 /// The recipient of a payment, differing based on whether they've hidden their identity with route
701 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
703 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
704 /// will be included in the final [`Route`].
706 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
708 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
709 /// Features supported by the payee.
711 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
713 features: Option<Bolt12InvoiceFeatures>,
715 /// The recipient included these route hints in their BOLT11 invoice.
717 /// The node id of the payee.
719 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
720 route_hints: Vec<RouteHint>,
721 /// Features supported by the payee.
723 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
724 /// does not contain any features.
726 /// [`for_keysend`]: PaymentParameters::for_keysend
727 features: Option<InvoiceFeatures>,
728 /// The minimum CLTV delta at the end of the route. This value must not be zero.
729 final_cltv_expiry_delta: u32,
734 fn node_id(&self) -> Option<PublicKey> {
736 Self::Clear { node_id, .. } => Some(*node_id),
740 fn node_features(&self) -> Option<NodeFeatures> {
742 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
743 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
746 fn supports_basic_mpp(&self) -> bool {
748 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
749 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
752 fn features(&self) -> Option<FeaturesRef> {
754 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
755 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
758 fn final_cltv_expiry_delta(&self) -> Option<u32> {
760 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
766 enum FeaturesRef<'a> {
767 Bolt11(&'a InvoiceFeatures),
768 Bolt12(&'a Bolt12InvoiceFeatures),
771 Bolt11(InvoiceFeatures),
772 Bolt12(Bolt12InvoiceFeatures),
776 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
778 Self::Bolt12(f) => Some(f),
782 fn bolt11(self) -> Option<InvoiceFeatures> {
784 Self::Bolt11(f) => Some(f),
790 impl<'a> Writeable for FeaturesRef<'a> {
791 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
793 Self::Bolt11(f) => Ok(f.write(w)?),
794 Self::Bolt12(f) => Ok(f.write(w)?),
799 impl ReadableArgs<bool> for Features {
800 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
801 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
802 Ok(Self::Bolt12(Readable::read(reader)?))
806 /// A list of hops along a payment path terminating with a channel to the recipient.
807 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
808 pub struct RouteHint(pub Vec<RouteHintHop>);
810 impl Writeable for RouteHint {
811 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
812 (self.0.len() as u64).write(writer)?;
813 for hop in self.0.iter() {
820 impl Readable for RouteHint {
821 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
822 let hop_count: u64 = Readable::read(reader)?;
823 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
824 for _ in 0..hop_count {
825 hops.push(Readable::read(reader)?);
831 /// A channel descriptor for a hop along a payment path.
832 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
833 pub struct RouteHintHop {
834 /// The node_id of the non-target end of the route
835 pub src_node_id: PublicKey,
836 /// The short_channel_id of this channel
837 pub short_channel_id: u64,
838 /// The fees which must be paid to use this channel
839 pub fees: RoutingFees,
840 /// The difference in CLTV values between this node and the next node.
841 pub cltv_expiry_delta: u16,
842 /// The minimum value, in msat, which must be relayed to the next hop.
843 pub htlc_minimum_msat: Option<u64>,
844 /// The maximum value in msat available for routing with a single HTLC.
845 pub htlc_maximum_msat: Option<u64>,
848 impl_writeable_tlv_based!(RouteHintHop, {
849 (0, src_node_id, required),
850 (1, htlc_minimum_msat, option),
851 (2, short_channel_id, required),
852 (3, htlc_maximum_msat, option),
854 (6, cltv_expiry_delta, required),
857 #[derive(Eq, PartialEq)]
858 struct RouteGraphNode {
860 lowest_fee_to_node: u64,
861 total_cltv_delta: u32,
862 // The maximum value a yet-to-be-constructed payment path might flow through this node.
863 // This value is upper-bounded by us by:
864 // - how much is needed for a path being constructed
865 // - how much value can channels following this node (up to the destination) can contribute,
866 // considering their capacity and fees
867 value_contribution_msat: u64,
868 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
869 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
870 path_htlc_minimum_msat: u64,
871 /// All penalties incurred from this hop on the way to the destination, as calculated using
873 path_penalty_msat: u64,
874 /// The number of hops walked up to this node.
875 path_length_to_node: u8,
878 impl cmp::Ord for RouteGraphNode {
879 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
880 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
881 .saturating_add(other.path_penalty_msat);
882 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
883 .saturating_add(self.path_penalty_msat);
884 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
888 impl cmp::PartialOrd for RouteGraphNode {
889 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
890 Some(self.cmp(other))
894 /// A wrapper around the various hop representations.
896 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
897 #[derive(Clone, Debug)]
898 enum CandidateRouteHop<'a> {
899 /// A hop from the payer, where the outbound liquidity is known.
901 details: &'a ChannelDetails,
903 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
905 info: DirectedChannelInfo<'a>,
906 short_channel_id: u64,
908 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
910 hint: &'a RouteHintHop,
914 impl<'a> CandidateRouteHop<'a> {
915 fn short_channel_id(&self) -> u64 {
917 CandidateRouteHop::FirstHop { details } => details.get_outbound_payment_scid().unwrap(),
918 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
919 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
923 // NOTE: This may alloc memory so avoid calling it in a hot code path.
924 fn features(&self) -> ChannelFeatures {
926 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
927 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
928 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
932 fn cltv_expiry_delta(&self) -> u32 {
934 CandidateRouteHop::FirstHop { .. } => 0,
935 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
936 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
940 fn htlc_minimum_msat(&self) -> u64 {
942 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat,
943 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
944 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
948 fn fees(&self) -> RoutingFees {
950 CandidateRouteHop::FirstHop { .. } => RoutingFees {
951 base_msat: 0, proportional_millionths: 0,
953 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
954 CandidateRouteHop::PrivateHop { hint } => hint.fees,
958 fn effective_capacity(&self) -> EffectiveCapacity {
960 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
961 liquidity_msat: details.next_outbound_htlc_limit_msat,
963 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
964 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }} =>
965 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
966 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }} =>
967 EffectiveCapacity::Infinite,
973 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
974 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
976 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
977 EffectiveCapacity::Infinite => u64::max_value(),
978 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
979 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
980 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
981 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
982 // expected to have been generated from up-to-date capacity information.
983 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
984 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
985 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
989 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
990 -> bool where I1::Item: PartialEq<I2::Item> {
992 let a = iter_a.next();
993 let b = iter_b.next();
994 if a.is_none() && b.is_none() { return true; }
995 if a.is_none() || b.is_none() { return false; }
996 if a.unwrap().ne(&b.unwrap()) { return false; }
1000 /// It's useful to keep track of the hops associated with the fees required to use them,
1001 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1002 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1003 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1005 struct PathBuildingHop<'a> {
1006 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
1007 // is a larger refactor and will require careful performance analysis.
1009 candidate: CandidateRouteHop<'a>,
1012 /// All the fees paid *after* this channel on the way to the destination
1013 next_hops_fee_msat: u64,
1014 /// Fee paid for the use of the current channel (see candidate.fees()).
1015 /// The value will be actually deducted from the counterparty balance on the previous link.
1016 hop_use_fee_msat: u64,
1017 /// Used to compare channels when choosing the for routing.
1018 /// Includes paying for the use of a hop and the following hops, as well as
1019 /// an estimated cost of reaching this hop.
1020 /// Might get stale when fees are recomputed. Primarily for internal use.
1021 total_fee_msat: u64,
1022 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1023 /// walk and may be invalid thereafter.
1024 path_htlc_minimum_msat: u64,
1025 /// All penalties incurred from this channel on the way to the destination, as calculated using
1026 /// channel scoring.
1027 path_penalty_msat: u64,
1028 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1029 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1030 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1031 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1032 /// avoid processing them again.
1033 was_processed: bool,
1034 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1035 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1036 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1037 // value_contribution_msat, which requires tracking it here. See comments below where it is
1038 // used for more info.
1039 value_contribution_msat: u64,
1042 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1043 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1044 let mut debug_struct = f.debug_struct("PathBuildingHop");
1046 .field("node_id", &self.node_id)
1047 .field("short_channel_id", &self.candidate.short_channel_id())
1048 .field("total_fee_msat", &self.total_fee_msat)
1049 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1050 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1051 .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)))
1052 .field("path_penalty_msat", &self.path_penalty_msat)
1053 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1054 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1055 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1056 let debug_struct = debug_struct
1057 .field("value_contribution_msat", &self.value_contribution_msat);
1058 debug_struct.finish()
1062 // Instantiated with a list of hops with correct data in them collected during path finding,
1063 // an instance of this struct should be further modified only via given methods.
1065 struct PaymentPath<'a> {
1066 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1069 impl<'a> PaymentPath<'a> {
1070 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1071 fn get_value_msat(&self) -> u64 {
1072 self.hops.last().unwrap().0.fee_msat
1075 fn get_path_penalty_msat(&self) -> u64 {
1076 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1079 fn get_total_fee_paid_msat(&self) -> u64 {
1080 if self.hops.len() < 1 {
1084 // Can't use next_hops_fee_msat because it gets outdated.
1085 for (i, (hop, _)) in self.hops.iter().enumerate() {
1086 if i != self.hops.len() - 1 {
1087 result += hop.fee_msat;
1093 fn get_cost_msat(&self) -> u64 {
1094 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1097 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1098 // to change fees may result in an inconsistency.
1100 // Sometimes we call this function right after constructing a path which is inconsistent in
1101 // that it the value being transferred has decreased while we were doing path finding, leading
1102 // to the fees being paid not lining up with the actual limits.
1104 // Note that this function is not aware of the available_liquidity limit, and thus does not
1105 // support increasing the value being transferred beyond what was selected during the initial
1107 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
1108 let mut total_fee_paid_msat = 0 as u64;
1109 for i in (0..self.hops.len()).rev() {
1110 let last_hop = i == self.hops.len() - 1;
1112 // For non-last-hop, this value will represent the fees paid on the current hop. It
1113 // will consist of the fees for the use of the next hop, and extra fees to match
1114 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1115 let mut cur_hop_fees_msat = 0;
1117 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1120 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1121 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1122 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1123 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1124 // set it too high just to maliciously take more fees by exploiting this
1125 // match htlc_minimum_msat logic.
1126 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1127 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1128 // Note that there is a risk that *previous hops* (those closer to us, as we go
1129 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1131 // This might make us end up with a broken route, although this should be super-rare
1132 // in practice, both because of how healthy channels look like, and how we pick
1133 // channels in add_entry.
1134 // Also, this can't be exploited more heavily than *announce a free path and fail
1136 cur_hop_transferred_amount_msat += extra_fees_msat;
1137 total_fee_paid_msat += extra_fees_msat;
1138 cur_hop_fees_msat += extra_fees_msat;
1142 // Final hop is a special case: it usually has just value_msat (by design), but also
1143 // it still could overpay for the htlc_minimum_msat.
1144 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1146 // Propagate updated fees for the use of the channels to one hop back, where they
1147 // will be actually paid (fee_msat). The last hop is handled above separately.
1148 cur_hop.fee_msat = cur_hop_fees_msat;
1151 // Fee for the use of the current hop which will be deducted on the previous hop.
1152 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1153 // this channel is free for us.
1155 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1156 cur_hop.hop_use_fee_msat = new_fee;
1157 total_fee_paid_msat += new_fee;
1159 // It should not be possible because this function is called only to reduce the
1160 // value. In that case, compute_fee was already called with the same fees for
1161 // larger amount and there was no overflow.
1170 /// Calculate the fees required to route the given amount over a channel with the given fees.
1171 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1172 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1173 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1177 /// Calculate the fees required to route the given amount over a channel with the given fees,
1178 /// saturating to [`u64::max_value`].
1179 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1180 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1181 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1182 .saturating_add(channel_fees.base_msat as u64)
1185 /// The default `features` we assume for a node in a route, when no `features` are known about that
1188 /// Default features are:
1189 /// * variable_length_onion_optional
1190 fn default_node_features() -> NodeFeatures {
1191 let mut features = NodeFeatures::empty();
1192 features.set_variable_length_onion_optional();
1196 struct LoggedPayeePubkey(Option<PublicKey>);
1197 impl fmt::Display for LoggedPayeePubkey {
1198 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1201 "payee node id ".fmt(f)?;
1205 "blinded payee".fmt(f)
1212 fn sort_first_hop_channels(
1213 channels: &mut Vec<&ChannelDetails>, used_channel_liquidities: &HashMap<(u64, bool), u64>,
1214 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1216 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1217 // most like to use.
1219 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1220 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1223 // Second, because simply always sorting in descending order would always use our largest
1224 // available outbound capacity, needlessly fragmenting our available channel capacities,
1225 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1226 // which have enough, but not too much, capacity for the payment.
1228 // Available outbound balances factor in liquidity already reserved for previously found paths.
1229 channels.sort_unstable_by(|chan_a, chan_b| {
1230 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1231 .saturating_sub(*used_channel_liquidities.get(&(chan_a.get_outbound_payment_scid().unwrap(),
1232 our_node_pubkey < &chan_a.counterparty.node_id)).unwrap_or(&0));
1233 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1234 .saturating_sub(*used_channel_liquidities.get(&(chan_b.get_outbound_payment_scid().unwrap(),
1235 our_node_pubkey < &chan_b.counterparty.node_id)).unwrap_or(&0));
1236 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1237 // Sort in descending order
1238 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1240 // Sort in ascending order
1241 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1246 /// Finds a route from us (payer) to the given target node (payee).
1248 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
1249 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1251 /// Private routing paths between a public node and the target may be included in `params.payee`.
1253 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1254 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1255 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1257 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1258 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1259 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1263 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
1264 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
1269 /// Panics if first_hops contains channels without short_channel_ids;
1270 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1272 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1273 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1274 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1275 pub fn find_route<L: Deref, GL: Deref, S: Score>(
1276 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1277 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1278 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1279 ) -> Result<Route, LightningError>
1280 where L::Target: Logger, GL::Target: Logger {
1281 let graph_lock = network_graph.read_only();
1282 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
1283 route_params.final_value_msat, logger, scorer, score_params,
1284 random_seed_bytes)?;
1285 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1289 pub(crate) fn get_route<L: Deref, S: Score>(
1290 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
1291 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, logger: L, scorer: &S, score_params: &S::ScoreParams,
1292 _random_seed_bytes: &[u8; 32]
1293 ) -> Result<Route, LightningError>
1294 where L::Target: Logger {
1295 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1296 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1297 // so use a dummy id for this in the blinded case.
1298 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1299 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1300 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1301 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1302 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1304 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1305 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1308 if final_value_msat > MAX_VALUE_MSAT {
1309 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1312 if final_value_msat == 0 {
1313 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1316 match &payment_params.payee {
1317 Payee::Clear { route_hints, node_id, .. } => {
1318 for route in route_hints.iter() {
1319 for hop in &route.0 {
1320 if hop.src_node_id == *node_id {
1321 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1326 _ => return Err(LightningError{err: "Routing to blinded paths isn't supported yet".to_owned(), action: ErrorAction::IgnoreError}),
1329 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1330 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1331 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});
1334 // The general routing idea is the following:
1335 // 1. Fill first/last hops communicated by the caller.
1336 // 2. Attempt to construct a path from payer to payee for transferring
1337 // any ~sufficient (described later) value.
1338 // If succeed, remember which channels were used and how much liquidity they have available,
1339 // so that future paths don't rely on the same liquidity.
1340 // 3. Proceed to the next step if:
1341 // - we hit the recommended target value;
1342 // - OR if we could not construct a new path. Any next attempt will fail too.
1343 // Otherwise, repeat step 2.
1344 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1345 // (not recommended value).
1346 // 5. If yes, proceed. If not, fail routing.
1347 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1348 // transferred up to the transfer target value.
1349 // 7. Reduce the value of the last path until we are sending only the target value.
1350 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1351 // them so that we're not sending two HTLCs along the same path.
1353 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1354 // distance from the payee
1356 // We are not a faithful Dijkstra's implementation because we can change values which impact
1357 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1358 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1359 // the value we are currently attempting to send over a path, we simply reduce the value being
1360 // sent along the path for any hops after that channel. This may imply that later fees (which
1361 // we've already tabulated) are lower because a smaller value is passing through the channels
1362 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1363 // channels which were selected earlier (and which may still be used for other paths without a
1364 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1367 // One potentially problematic case for this algorithm would be if there are many
1368 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1369 // graph walking), we may never find a path which is not liquidity-limited and has lower
1370 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1371 // Because we only consider paths with at least 5% of the total value being sent, the damage
1372 // from such a case should be limited, however this could be further reduced in the future by
1373 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1374 // limits for the purposes of fee calculation.
1376 // Alternatively, we could store more detailed path information in the heap (targets, below)
1377 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1378 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1379 // and practically (as we would need to store dynamically-allocated path information in heap
1380 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1381 // results of such an algorithm would likely be biased towards lower-value paths.
1383 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1384 // outside of our current search value, running a path search more times to gather candidate
1385 // paths at different values. While this may be acceptable, further path searches may increase
1386 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1387 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1388 // the same time, remaining generic across different payment values.
1390 let network_channels = network_graph.channels();
1391 let network_nodes = network_graph.nodes();
1393 if payment_params.max_path_count == 0 {
1394 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1397 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1398 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1400 let allow_mpp = if payment_params.max_path_count == 1 {
1402 } else if payment_params.payee.supports_basic_mpp() {
1404 } else if let Some(payee) = payee_node_id_opt {
1405 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1406 |info| info.features.supports_basic_mpp()))
1409 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1410 LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
1411 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1414 // Prepare the data we'll use for payee-to-payer search by
1415 // inserting first hops suggested by the caller as targets.
1416 // Our search will then attempt to reach them while traversing from the payee node.
1417 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1418 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1419 if let Some(hops) = first_hops {
1421 if chan.get_outbound_payment_scid().is_none() {
1422 panic!("first_hops should be filled in with usable channels, not pending ones");
1424 if chan.counterparty.node_id == *our_node_pubkey {
1425 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1428 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1429 .or_insert(Vec::new())
1432 if first_hop_targets.is_empty() {
1433 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1437 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1438 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1439 // adding duplicate entries when we find a better path to a given node.
1440 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1442 // Map from node_id to information about the best current path to that node, including feerate
1444 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1446 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1447 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1448 // htlc_minimum with extra fees while still finding a cheaper path.
1449 let mut hit_minimum_limit;
1451 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1452 // We start with a path_value of the exact amount we want, and if that generates a route we may
1453 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1454 // amount we want in total across paths, selecting the best subset at the end.
1455 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1456 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1457 let mut path_value_msat = final_value_msat;
1459 // Routing Fragmentation Mitigation heuristic:
1461 // Routing fragmentation across many payment paths increases the overall routing
1462 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1463 // Taking too many smaller paths also increases the chance of payment failure.
1464 // Thus to avoid this effect, we require from our collected links to provide
1465 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1466 // This requirement is currently set to be 1/max_path_count of the payment
1467 // value to ensure we only ever return routes that do not violate this limit.
1468 let minimal_value_contribution_msat: u64 = if allow_mpp {
1469 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1474 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1475 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1476 // drop the requirement by setting this to 0.
1477 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1479 // Keep track of how much liquidity has been used in selected channels. Used to determine
1480 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
1481 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
1482 // liquidity used in one direction will not offset any used in the opposite direction.
1483 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
1484 HashMap::with_capacity(network_nodes.len());
1486 // Keeping track of how much value we already collected across other paths. Helps to decide
1487 // when we want to stop looking for new paths.
1488 let mut already_collected_value_msat = 0;
1490 for (_, channels) in first_hop_targets.iter_mut() {
1491 sort_first_hop_channels(channels, &used_channel_liquidities, recommended_value_msat,
1495 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1496 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1498 macro_rules! add_entry {
1499 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1500 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1501 // since that value has to be transferred over this channel.
1502 // Returns whether this channel caused an update to `targets`.
1503 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1504 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1505 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1506 // We "return" whether we updated the path at the end, and how much we can route via
1507 // this channel, via this:
1508 let mut did_add_update_path_to_src_node = None;
1509 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1510 // practice these cases should be caught earlier:
1511 // - for regular channels at channel announcement (TODO)
1512 // - for first and last hops early in get_route
1513 if $src_node_id != $dest_node_id {
1514 let short_channel_id = $candidate.short_channel_id();
1515 let effective_capacity = $candidate.effective_capacity();
1516 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1518 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1519 // It may be misleading because we might later choose to reduce the value transferred
1520 // over these channels, and the channel which was insufficient might become sufficient.
1521 // Worst case: we drop a good channel here because it can't cover the high following
1522 // fees caused by one expensive channel, but then this channel could have been used
1523 // if the amount being transferred over this path is lower.
1524 // We do this for now, but this is a subject for removal.
1525 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1526 let used_liquidity_msat = used_channel_liquidities
1527 .get(&(short_channel_id, $src_node_id < $dest_node_id))
1528 .map_or(0, |used_liquidity_msat| {
1529 available_value_contribution_msat = available_value_contribution_msat
1530 .saturating_sub(*used_liquidity_msat);
1531 *used_liquidity_msat
1534 // Verify the liquidity offered by this channel complies to the minimal contribution.
1535 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1536 // Do not consider candidate hops that would exceed the maximum path length.
1537 let path_length_to_node = $next_hops_path_length + 1;
1538 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1540 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1541 // In order to already account for some of the privacy enhancing random CLTV
1542 // expiry delta offset we add on top later, we subtract a rough estimate
1543 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1544 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1545 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1546 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1547 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1548 .saturating_add($candidate.cltv_expiry_delta());
1549 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1551 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1552 // Includes paying fees for the use of the following channels.
1553 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1554 Some(result) => result,
1555 // Can't overflow due to how the values were computed right above.
1556 None => unreachable!(),
1558 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1559 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1560 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1562 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1563 let may_overpay_to_meet_path_minimum_msat =
1564 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1565 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1566 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1567 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1569 let payment_failed_on_this_channel =
1570 payment_params.previously_failed_channels.contains(&short_channel_id);
1572 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1573 // bother considering this channel. If retrying with recommended_value_msat may
1574 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1575 // around again with a higher amount.
1576 if !contributes_sufficient_value || exceeds_max_path_length ||
1577 exceeds_cltv_delta_limit || payment_failed_on_this_channel {
1578 // Path isn't useful, ignore it and move on.
1579 } else if may_overpay_to_meet_path_minimum_msat {
1580 hit_minimum_limit = true;
1581 } else if over_path_minimum_msat {
1582 // Note that low contribution here (limited by available_liquidity_msat)
1583 // might violate htlc_minimum_msat on the hops which are next along the
1584 // payment path (upstream to the payee). To avoid that, we recompute
1585 // path fees knowing the final path contribution after constructing it.
1586 let path_htlc_minimum_msat = cmp::max(
1587 compute_fees_saturating($next_hops_path_htlc_minimum_msat, $candidate.fees())
1588 .saturating_add($next_hops_path_htlc_minimum_msat),
1589 $candidate.htlc_minimum_msat());
1590 let hm_entry = dist.entry($src_node_id);
1591 let old_entry = hm_entry.or_insert_with(|| {
1592 // If there was previously no known way to access the source node
1593 // (recall it goes payee-to-payer) of short_channel_id, first add a
1594 // semi-dummy record just to compute the fees to reach the source node.
1595 // This will affect our decision on selecting short_channel_id
1596 // as a way to reach the $dest_node_id.
1598 node_id: $dest_node_id.clone(),
1599 candidate: $candidate.clone(),
1601 next_hops_fee_msat: u64::max_value(),
1602 hop_use_fee_msat: u64::max_value(),
1603 total_fee_msat: u64::max_value(),
1604 path_htlc_minimum_msat,
1605 path_penalty_msat: u64::max_value(),
1606 was_processed: false,
1607 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1608 value_contribution_msat,
1612 #[allow(unused_mut)] // We only use the mut in cfg(test)
1613 let mut should_process = !old_entry.was_processed;
1614 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1616 // In test/fuzzing builds, we do extra checks to make sure the skipping
1617 // of already-seen nodes only happens in cases we expect (see below).
1618 if !should_process { should_process = true; }
1622 let mut hop_use_fee_msat = 0;
1623 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1625 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1626 // will have the same effective-fee
1627 if $src_node_id != our_node_id {
1628 // Note that `u64::max_value` means we'll always fail the
1629 // `old_entry.total_fee_msat > total_fee_msat` check below
1630 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1631 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1634 let channel_usage = ChannelUsage {
1635 amount_msat: amount_to_transfer_over_msat,
1636 inflight_htlc_msat: used_liquidity_msat,
1639 let channel_penalty_msat = scorer.channel_penalty_msat(
1640 short_channel_id, &$src_node_id, &$dest_node_id, channel_usage, score_params
1642 let path_penalty_msat = $next_hops_path_penalty_msat
1643 .saturating_add(channel_penalty_msat);
1644 let new_graph_node = RouteGraphNode {
1645 node_id: $src_node_id,
1646 lowest_fee_to_node: total_fee_msat,
1647 total_cltv_delta: hop_total_cltv_delta,
1648 value_contribution_msat,
1649 path_htlc_minimum_msat,
1651 path_length_to_node,
1654 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1655 // if this way is cheaper than the already known
1656 // (considering the cost to "reach" this channel from the route destination,
1657 // the cost of using this channel,
1658 // and the cost of routing to the source node of this channel).
1659 // Also, consider that htlc_minimum_msat_difference, because we might end up
1660 // paying it. Consider the following exploit:
1661 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1662 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1663 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1664 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1666 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1667 // but it may require additional tracking - we don't want to double-count
1668 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1669 // can't use something that may decrease on future hops.
1670 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1671 .saturating_add(old_entry.path_penalty_msat);
1672 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1673 .saturating_add(path_penalty_msat);
1675 if !old_entry.was_processed && new_cost < old_cost {
1676 targets.push(new_graph_node);
1677 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1678 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1679 old_entry.total_fee_msat = total_fee_msat;
1680 old_entry.node_id = $dest_node_id.clone();
1681 old_entry.candidate = $candidate.clone();
1682 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1683 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1684 old_entry.path_penalty_msat = path_penalty_msat;
1685 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1687 old_entry.value_contribution_msat = value_contribution_msat;
1689 did_add_update_path_to_src_node = Some(value_contribution_msat);
1690 } else if old_entry.was_processed && new_cost < old_cost {
1691 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1693 // If we're skipping processing a node which was previously
1694 // processed even though we found another path to it with a
1695 // cheaper fee, check that it was because the second path we
1696 // found (which we are processing now) has a lower value
1697 // contribution due to an HTLC minimum limit.
1699 // e.g. take a graph with two paths from node 1 to node 2, one
1700 // through channel A, and one through channel B. Channel A and
1701 // B are both in the to-process heap, with their scores set by
1702 // a higher htlc_minimum than fee.
1703 // Channel A is processed first, and the channels onwards from
1704 // node 1 are added to the to-process heap. Thereafter, we pop
1705 // Channel B off of the heap, note that it has a much more
1706 // restrictive htlc_maximum_msat, and recalculate the fees for
1707 // all of node 1's channels using the new, reduced, amount.
1709 // This would be bogus - we'd be selecting a higher-fee path
1710 // with a lower htlc_maximum_msat instead of the one we'd
1711 // already decided to use.
1712 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1714 value_contribution_msat + path_penalty_msat <
1715 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1723 did_add_update_path_to_src_node
1727 let default_node_features = default_node_features();
1729 // Find ways (channels with destination) to reach a given node and store them
1730 // in the corresponding data structures (routing graph etc).
1731 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1732 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1733 // This data can later be helpful to optimize routing (pay lower fees).
1734 macro_rules! add_entries_to_cheapest_to_target_node {
1735 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1736 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1737 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1738 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1739 let was_processed = elem.was_processed;
1740 elem.was_processed = true;
1743 // Entries are added to dist in add_entry!() when there is a channel from a node.
1744 // Because there are no channels from payee, it will not have a dist entry at this point.
1745 // If we're processing any other node, it is always be the result of a channel from it.
1746 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
1751 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1752 for details in first_channels {
1753 let candidate = CandidateRouteHop::FirstHop { details };
1754 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1755 $next_hops_value_contribution,
1756 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1757 $next_hops_cltv_delta, $next_hops_path_length);
1761 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1764 &default_node_features
1767 if !features.requires_unknown_bits() {
1768 for chan_id in $node.channels.iter() {
1769 let chan = network_channels.get(chan_id).unwrap();
1770 if !chan.features.requires_unknown_bits() {
1771 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1772 if first_hops.is_none() || *source != our_node_id {
1773 if directed_channel.direction().enabled {
1774 let candidate = CandidateRouteHop::PublicHop {
1775 info: directed_channel,
1776 short_channel_id: *chan_id,
1778 add_entry!(candidate, *source, $node_id,
1779 $fee_to_target_msat,
1780 $next_hops_value_contribution,
1781 $next_hops_path_htlc_minimum_msat,
1782 $next_hops_path_penalty_msat,
1783 $next_hops_cltv_delta, $next_hops_path_length);
1794 let mut payment_paths = Vec::<PaymentPath>::new();
1796 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1797 'paths_collection: loop {
1798 // For every new path, start from scratch, except for used_channel_liquidities, which
1799 // helps to avoid reusing previously selected paths in future iterations.
1802 hit_minimum_limit = false;
1804 // If first hop is a private channel and the only way to reach the payee, this is the only
1805 // place where it could be added.
1806 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
1807 for details in first_channels {
1808 let candidate = CandidateRouteHop::FirstHop { details };
1809 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
1810 0, 0u64, 0, 0).is_some();
1811 log_trace!(logger, "{} direct route to payee via SCID {}",
1812 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1816 // Add the payee as a target, so that the payee-to-payer
1817 // search algorithm knows what to start with.
1818 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
1819 // The payee is not in our network graph, so nothing to add here.
1820 // There is still a chance of reaching them via last_hops though,
1821 // so don't yet fail the payment here.
1822 // If not, targets.pop() will not even let us enter the loop in step 2.
1825 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
1830 // If a caller provided us with last hops, add them to routing targets. Since this happens
1831 // earlier than general path finding, they will be somewhat prioritized, although currently
1832 // it matters only if the fees are exactly the same.
1833 let route_hints = match &payment_params.payee {
1834 Payee::Clear { route_hints, .. } => route_hints,
1835 _ => return Err(LightningError{err: "Routing to blinded paths isn't supported yet".to_owned(), action: ErrorAction::IgnoreError}),
1837 for route in route_hints.iter().filter(|route| !route.0.is_empty()) {
1838 let first_hop_in_route = &(route.0)[0];
1839 let have_hop_src_in_graph =
1840 // Only add the hops in this route to our candidate set if either
1841 // we have a direct channel to the first hop or the first hop is
1842 // in the regular network graph.
1843 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1844 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1845 if have_hop_src_in_graph {
1846 // We start building the path from reverse, i.e., from payee
1847 // to the first RouteHintHop in the path.
1848 let hop_iter = route.0.iter().rev();
1849 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
1850 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1851 let mut hop_used = true;
1852 let mut aggregate_next_hops_fee_msat: u64 = 0;
1853 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1854 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1855 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1856 let mut aggregate_next_hops_path_length: u8 = 0;
1857 let mut aggregate_path_contribution_msat = path_value_msat;
1859 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1860 let source = NodeId::from_pubkey(&hop.src_node_id);
1861 let target = NodeId::from_pubkey(&prev_hop_id);
1862 let candidate = network_channels
1863 .get(&hop.short_channel_id)
1864 .and_then(|channel| channel.as_directed_to(&target))
1865 .map(|(info, _)| CandidateRouteHop::PublicHop {
1867 short_channel_id: hop.short_channel_id,
1869 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1871 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
1872 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
1873 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
1874 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
1876 aggregate_path_contribution_msat = hop_used_msat;
1878 // If this hop was not used then there is no use checking the preceding
1879 // hops in the RouteHint. We can break by just searching for a direct
1880 // channel between last checked hop and first_hop_targets.
1884 let used_liquidity_msat = used_channel_liquidities
1885 .get(&(hop.short_channel_id, source < target)).copied().unwrap_or(0);
1886 let channel_usage = ChannelUsage {
1887 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
1888 inflight_htlc_msat: used_liquidity_msat,
1889 effective_capacity: candidate.effective_capacity(),
1891 let channel_penalty_msat = scorer.channel_penalty_msat(
1892 hop.short_channel_id, &source, &target, channel_usage, score_params
1894 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1895 .saturating_add(channel_penalty_msat);
1897 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1898 .saturating_add(hop.cltv_expiry_delta as u32);
1900 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1903 // Searching for a direct channel between last checked hop and first_hop_targets
1904 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&prev_hop_id)) {
1905 sort_first_hop_channels(first_channels, &used_channel_liquidities,
1906 recommended_value_msat, our_node_pubkey);
1907 for details in first_channels {
1908 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
1909 add_entry!(first_hop_candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1910 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
1911 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
1912 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
1920 // In the next values of the iterator, the aggregate fees already reflects
1921 // the sum of value sent from payer (final_value_msat) and routing fees
1922 // for the last node in the RouteHint. We need to just add the fees to
1923 // route through the current node so that the preceding node (next iteration)
1925 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1926 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1927 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1929 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1930 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1931 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1932 .checked_add(hop_htlc_minimum_msat_inc);
1933 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1935 if idx == route.0.len() - 1 {
1936 // The last hop in this iterator is the first hop in
1937 // overall RouteHint.
1938 // If this hop connects to a node with which we have a direct channel,
1939 // ignore the network graph and, if the last hop was added, add our
1940 // direct channel to the candidate set.
1942 // Note that we *must* check if the last hop was added as `add_entry`
1943 // always assumes that the third argument is a node to which we have a
1945 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
1946 sort_first_hop_channels(first_channels, &used_channel_liquidities,
1947 recommended_value_msat, our_node_pubkey);
1948 for details in first_channels {
1949 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
1950 add_entry!(first_hop_candidate, our_node_id,
1951 NodeId::from_pubkey(&hop.src_node_id),
1952 aggregate_next_hops_fee_msat,
1953 aggregate_path_contribution_msat,
1954 aggregate_next_hops_path_htlc_minimum_msat,
1955 aggregate_next_hops_path_penalty_msat,
1956 aggregate_next_hops_cltv_delta,
1957 aggregate_next_hops_path_length);
1965 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1967 // At this point, targets are filled with the data from first and
1968 // last hops communicated by the caller, and the payment receiver.
1969 let mut found_new_path = false;
1972 // If this loop terminates due the exhaustion of targets, two situations are possible:
1973 // - not enough outgoing liquidity:
1974 // 0 < already_collected_value_msat < final_value_msat
1975 // - enough outgoing liquidity:
1976 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1977 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1978 // paths_collection will be stopped because found_new_path==false.
1979 // This is not necessarily a routing failure.
1980 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, mut value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, path_length_to_node, .. }) = targets.pop() {
1982 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1983 // traversing the graph and arrange the path out of what we found.
1984 if node_id == our_node_id {
1985 let mut new_entry = dist.remove(&our_node_id).unwrap();
1986 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1989 let mut features_set = false;
1990 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1991 for details in first_channels {
1992 if details.get_outbound_payment_scid().unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1993 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1994 features_set = true;
2000 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2001 if let Some(node_info) = node.announcement_info.as_ref() {
2002 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2004 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2007 // We can fill in features for everything except hops which were
2008 // provided via the invoice we're paying. We could guess based on the
2009 // recipient's features but for now we simply avoid guessing at all.
2013 // Means we succesfully traversed from the payer to the payee, now
2014 // save this path for the payment route. Also, update the liquidity
2015 // remaining on the used hops, so that we take them into account
2016 // while looking for more paths.
2017 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2021 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2022 Some(payment_hop) => payment_hop,
2023 // We can't arrive at None because, if we ever add an entry to targets,
2024 // we also fill in the entry in dist (see add_entry!).
2025 None => unreachable!(),
2027 // We "propagate" the fees one hop backward (topologically) here,
2028 // so that fees paid for a HTLC forwarding on the current channel are
2029 // associated with the previous channel (where they will be subtracted).
2030 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2031 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2033 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2034 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2036 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2037 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2039 let mut payment_path = PaymentPath {hops: ordered_hops};
2041 // We could have possibly constructed a slightly inconsistent path: since we reduce
2042 // value being transferred along the way, we could have violated htlc_minimum_msat
2043 // on some channels we already passed (assuming dest->source direction). Here, we
2044 // recompute the fees again, so that if that's the case, we match the currently
2045 // underpaid htlc_minimum_msat with fees.
2046 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2047 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
2048 payment_path.update_value_and_recompute_fees(value_contribution_msat);
2050 // Since a path allows to transfer as much value as
2051 // the smallest channel it has ("bottleneck"), we should recompute
2052 // the fees so sender HTLC don't overpay fees when traversing
2053 // larger channels than the bottleneck. This may happen because
2054 // when we were selecting those channels we were not aware how much value
2055 // this path will transfer, and the relative fee for them
2056 // might have been computed considering a larger value.
2057 // Remember that we used these channels so that we don't rely
2058 // on the same liquidity in future paths.
2059 let mut prevented_redundant_path_selection = false;
2060 let prev_hop_iter = core::iter::once(&our_node_id)
2061 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2062 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2063 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2064 let used_liquidity_msat = used_channel_liquidities
2065 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
2066 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2067 .or_insert(spent_on_hop_msat);
2068 let hop_capacity = hop.candidate.effective_capacity();
2069 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2070 if *used_liquidity_msat == hop_max_msat {
2071 // If this path used all of this channel's available liquidity, we know
2072 // this path will not be selected again in the next loop iteration.
2073 prevented_redundant_path_selection = true;
2075 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2077 if !prevented_redundant_path_selection {
2078 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2079 // we'll probably end up picking the same path again on the next iteration.
2080 // Decrease the available liquidity of a hop in the middle of the path.
2081 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
2082 let exhausted = u64::max_value();
2083 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
2084 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
2085 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
2088 // Track the total amount all our collected paths allow to send so that we know
2089 // when to stop looking for more paths
2090 already_collected_value_msat += value_contribution_msat;
2092 payment_paths.push(payment_path);
2093 found_new_path = true;
2094 break 'path_construction;
2097 // If we found a path back to the payee, we shouldn't try to process it again. This is
2098 // the equivalent of the `elem.was_processed` check in
2099 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2100 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2102 // Otherwise, since the current target node is not us,
2103 // keep "unrolling" the payment graph from payee to payer by
2104 // finding a way to reach the current target from the payer side.
2105 match network_nodes.get(&node_id) {
2108 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2109 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2110 total_cltv_delta, path_length_to_node);
2116 if !found_new_path && channel_saturation_pow_half != 0 {
2117 channel_saturation_pow_half = 0;
2118 continue 'paths_collection;
2120 // If we don't support MPP, no use trying to gather more value ever.
2121 break 'paths_collection;
2125 // Stop either when the recommended value is reached or if no new path was found in this
2127 // In the latter case, making another path finding attempt won't help,
2128 // because we deterministically terminated the search due to low liquidity.
2129 if !found_new_path && channel_saturation_pow_half != 0 {
2130 channel_saturation_pow_half = 0;
2131 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2132 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2133 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2134 break 'paths_collection;
2135 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2136 // Further, if this was our first walk of the graph, and we weren't limited by an
2137 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2138 // limited by an htlc_minimum_msat value, find another path with a higher value,
2139 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2140 // still keeping a lower total fee than this path.
2141 if !hit_minimum_limit {
2142 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2143 break 'paths_collection;
2145 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
2146 path_value_msat = recommended_value_msat;
2151 if payment_paths.len() == 0 {
2152 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2155 if already_collected_value_msat < final_value_msat {
2156 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2160 let mut selected_route = payment_paths;
2162 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2163 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2165 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2166 // the value they contribute towards the payment amount.
2167 // We sort in descending order as we will remove from the front in `retain`, next.
2168 selected_route.sort_unstable_by(|a, b|
2169 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2170 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2173 // We should make sure that at least 1 path left.
2174 let mut paths_left = selected_route.len();
2175 selected_route.retain(|path| {
2176 if paths_left == 1 {
2179 let path_value_msat = path.get_value_msat();
2180 if path_value_msat <= overpaid_value_msat {
2181 overpaid_value_msat -= path_value_msat;
2187 debug_assert!(selected_route.len() > 0);
2189 if overpaid_value_msat != 0 {
2191 // Now, subtract the remaining overpaid value from the most-expensive path.
2192 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2193 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2194 selected_route.sort_unstable_by(|a, b| {
2195 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2196 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2197 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2199 let expensive_payment_path = selected_route.first_mut().unwrap();
2201 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2202 // can't go negative.
2203 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2204 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2208 // Sort by the path itself and combine redundant paths.
2209 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2210 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2212 selected_route.sort_unstable_by_key(|path| {
2213 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
2214 debug_assert!(path.hops.len() <= key.len());
2215 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
2220 for idx in 0..(selected_route.len() - 1) {
2221 if idx + 1 >= selected_route.len() { break; }
2222 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
2223 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
2224 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2225 selected_route[idx].update_value_and_recompute_fees(new_value);
2226 selected_route.remove(idx + 1);
2230 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
2231 for payment_path in selected_route {
2232 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
2234 pubkey: PublicKey::from_slice(payment_hop.node_id.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &payment_hop.node_id), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2235 node_features: node_features.clone(),
2236 short_channel_id: payment_hop.candidate.short_channel_id(),
2237 channel_features: payment_hop.candidate.features(),
2238 fee_msat: payment_hop.fee_msat,
2239 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
2241 }).collect::<Vec<_>>();
2242 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2243 // applicable for the previous hop.
2244 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
2245 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
2247 selected_paths.push(path);
2249 // Make sure we would never create a route with more paths than we allow.
2250 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
2252 if let Some(node_features) = payment_params.payee.node_features() {
2253 for path in selected_paths.iter_mut() {
2254 if let Ok(route_hop) = path.last_mut().unwrap() {
2255 route_hop.node_features = node_features.clone();
2260 let mut paths: Vec<Path> = Vec::new();
2261 for results_vec in selected_paths {
2262 let mut hops = Vec::with_capacity(results_vec.len());
2263 for res in results_vec { hops.push(res?); }
2264 paths.push(Path { hops, blinded_tail: None });
2268 payment_params: Some(payment_params.clone()),
2270 log_info!(logger, "Got route: {}", log_route!(route));
2274 // When an adversarial intermediary node observes a payment, it may be able to infer its
2275 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2276 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2277 // payment path by adding a randomized 'shadow route' offset to the final hop.
2278 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2279 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2281 let network_channels = network_graph.channels();
2282 let network_nodes = network_graph.nodes();
2284 for path in route.paths.iter_mut() {
2285 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2287 // Remember the last three nodes of the random walk and avoid looping back on them.
2288 // Init with the last three nodes from the actual path, if possible.
2289 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2290 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2291 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2293 // Choose the last publicly known node as the starting point for the random walk.
2294 let mut cur_hop: Option<NodeId> = None;
2295 let mut path_nonce = [0u8; 12];
2296 if let Some(starting_hop) = path.hops.iter().rev()
2297 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2298 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2299 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2302 // Init PRNG with the path-dependant nonce, which is static for private paths.
2303 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2304 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2306 // Pick a random path length in [1 .. 3]
2307 prng.process_in_place(&mut random_path_bytes);
2308 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2310 for random_hop in 0..random_walk_length {
2311 // If we don't find a suitable offset in the public network graph, we default to
2312 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2313 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2315 if let Some(cur_node_id) = cur_hop {
2316 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2317 // Randomly choose the next unvisited hop.
2318 prng.process_in_place(&mut random_path_bytes);
2319 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2320 .checked_rem(cur_node.channels.len())
2321 .and_then(|index| cur_node.channels.get(index))
2322 .and_then(|id| network_channels.get(id)) {
2323 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2324 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2325 nodes_to_avoid[random_hop] = *next_id;
2326 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2327 cur_hop = Some(*next_id);
2334 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2335 .checked_add(random_hop_offset)
2336 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2339 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2340 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2341 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2343 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2344 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2345 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2346 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2347 max_path_offset = cmp::max(
2348 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2349 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2350 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2352 // Add 'shadow' CLTV offset to the final hop
2353 if let Some(tail) = path.blinded_tail.as_mut() {
2354 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2355 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2357 if let Some(last_hop) = path.hops.last_mut() {
2358 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2359 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2364 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2365 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2367 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2368 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2369 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2370 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2371 ) -> Result<Route, LightningError>
2372 where L::Target: Logger, GL::Target: Logger {
2373 let graph_lock = network_graph.read_only();
2374 let mut route = build_route_from_hops_internal(
2375 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
2376 route_params.final_value_msat, logger, random_seed_bytes)?;
2377 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2381 fn build_route_from_hops_internal<L: Deref>(
2382 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
2383 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, logger: L,
2384 random_seed_bytes: &[u8; 32]
2385 ) -> Result<Route, LightningError> where L::Target: Logger {
2388 our_node_id: NodeId,
2389 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2392 impl Score for HopScorer {
2393 type ScoreParams = ();
2394 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2395 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2397 let mut cur_id = self.our_node_id;
2398 for i in 0..self.hop_ids.len() {
2399 if let Some(next_id) = self.hop_ids[i] {
2400 if cur_id == *source && next_id == *target {
2411 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
2413 fn payment_path_successful(&mut self, _path: &Path) {}
2415 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
2417 fn probe_successful(&mut self, _path: &Path) {}
2420 impl<'a> Writeable for HopScorer {
2422 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2427 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2428 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2431 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2432 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2433 for i in 0..hops.len() {
2434 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2437 let scorer = HopScorer { our_node_id, hop_ids };
2439 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
2440 logger, &scorer, &(), random_seed_bytes)
2445 use crate::blinded_path::{BlindedHop, BlindedPath};
2446 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2447 use crate::routing::utxo::UtxoResult;
2448 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2449 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2450 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
2451 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, Score, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2452 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2453 use crate::chain::transaction::OutPoint;
2454 use crate::sign::EntropySource;
2455 use crate::ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
2456 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2457 use crate::ln::channelmanager;
2458 use crate::util::config::UserConfig;
2459 use crate::util::test_utils as ln_test_utils;
2460 use crate::util::chacha20::ChaCha20;
2461 use crate::util::ser::{Readable, Writeable};
2463 use crate::util::ser::Writer;
2465 use bitcoin::hashes::Hash;
2466 use bitcoin::network::constants::Network;
2467 use bitcoin::blockdata::constants::genesis_block;
2468 use bitcoin::blockdata::script::Builder;
2469 use bitcoin::blockdata::opcodes;
2470 use bitcoin::blockdata::transaction::TxOut;
2474 use bitcoin::secp256k1::{PublicKey,SecretKey};
2475 use bitcoin::secp256k1::Secp256k1;
2477 use crate::io::Cursor;
2478 use crate::prelude::*;
2479 use crate::sync::Arc;
2481 use core::convert::TryInto;
2483 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2484 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2485 channelmanager::ChannelDetails {
2486 channel_id: [0; 32],
2487 counterparty: channelmanager::ChannelCounterparty {
2490 unspendable_punishment_reserve: 0,
2491 forwarding_info: None,
2492 outbound_htlc_minimum_msat: None,
2493 outbound_htlc_maximum_msat: None,
2495 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2498 outbound_scid_alias: None,
2499 inbound_scid_alias: None,
2500 channel_value_satoshis: 0,
2503 outbound_capacity_msat,
2504 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2505 next_outbound_htlc_minimum_msat: 0,
2506 inbound_capacity_msat: 42,
2507 unspendable_punishment_reserve: None,
2508 confirmations_required: None,
2509 confirmations: None,
2510 force_close_spend_delay: None,
2511 is_outbound: true, is_channel_ready: true,
2512 is_usable: true, is_public: true,
2513 inbound_htlc_minimum_msat: None,
2514 inbound_htlc_maximum_msat: None,
2516 feerate_sat_per_1000_weight: None
2521 fn simple_route_test() {
2522 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2523 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2524 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2525 let scorer = ln_test_utils::TestScorer::new();
2526 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2527 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2529 // Simple route to 2 via 1
2531 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 0, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2532 assert_eq!(err, "Cannot send a payment of 0 msat");
2533 } else { panic!(); }
2535 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2536 assert_eq!(route.paths[0].hops.len(), 2);
2538 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2539 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2540 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2541 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2542 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2543 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2545 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2546 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2547 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2548 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2549 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2550 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2554 fn invalid_first_hop_test() {
2555 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2556 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2557 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2558 let scorer = ln_test_utils::TestScorer::new();
2559 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2560 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2562 // Simple route to 2 via 1
2564 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2566 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2567 get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2568 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2569 } else { panic!(); }
2571 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2572 assert_eq!(route.paths[0].hops.len(), 2);
2576 fn htlc_minimum_test() {
2577 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2578 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2579 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2580 let scorer = ln_test_utils::TestScorer::new();
2581 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2582 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2584 // Simple route to 2 via 1
2586 // Disable other paths
2587 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2588 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2589 short_channel_id: 12,
2591 flags: 2, // to disable
2592 cltv_expiry_delta: 0,
2593 htlc_minimum_msat: 0,
2594 htlc_maximum_msat: MAX_VALUE_MSAT,
2596 fee_proportional_millionths: 0,
2597 excess_data: Vec::new()
2599 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2600 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2601 short_channel_id: 3,
2603 flags: 2, // to disable
2604 cltv_expiry_delta: 0,
2605 htlc_minimum_msat: 0,
2606 htlc_maximum_msat: MAX_VALUE_MSAT,
2608 fee_proportional_millionths: 0,
2609 excess_data: Vec::new()
2611 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2612 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2613 short_channel_id: 13,
2615 flags: 2, // to disable
2616 cltv_expiry_delta: 0,
2617 htlc_minimum_msat: 0,
2618 htlc_maximum_msat: MAX_VALUE_MSAT,
2620 fee_proportional_millionths: 0,
2621 excess_data: Vec::new()
2623 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2624 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2625 short_channel_id: 6,
2627 flags: 2, // to disable
2628 cltv_expiry_delta: 0,
2629 htlc_minimum_msat: 0,
2630 htlc_maximum_msat: MAX_VALUE_MSAT,
2632 fee_proportional_millionths: 0,
2633 excess_data: Vec::new()
2635 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2636 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2637 short_channel_id: 7,
2639 flags: 2, // to disable
2640 cltv_expiry_delta: 0,
2641 htlc_minimum_msat: 0,
2642 htlc_maximum_msat: MAX_VALUE_MSAT,
2644 fee_proportional_millionths: 0,
2645 excess_data: Vec::new()
2648 // Check against amount_to_transfer_over_msat.
2649 // Set minimal HTLC of 200_000_000 msat.
2650 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2651 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2652 short_channel_id: 2,
2655 cltv_expiry_delta: 0,
2656 htlc_minimum_msat: 200_000_000,
2657 htlc_maximum_msat: MAX_VALUE_MSAT,
2659 fee_proportional_millionths: 0,
2660 excess_data: Vec::new()
2663 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2665 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2666 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2667 short_channel_id: 4,
2670 cltv_expiry_delta: 0,
2671 htlc_minimum_msat: 0,
2672 htlc_maximum_msat: 199_999_999,
2674 fee_proportional_millionths: 0,
2675 excess_data: Vec::new()
2678 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2679 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2680 assert_eq!(err, "Failed to find a path to the given destination");
2681 } else { panic!(); }
2683 // Lift the restriction on the first hop.
2684 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2685 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2686 short_channel_id: 2,
2689 cltv_expiry_delta: 0,
2690 htlc_minimum_msat: 0,
2691 htlc_maximum_msat: MAX_VALUE_MSAT,
2693 fee_proportional_millionths: 0,
2694 excess_data: Vec::new()
2697 // A payment above the minimum should pass
2698 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2699 assert_eq!(route.paths[0].hops.len(), 2);
2703 fn htlc_minimum_overpay_test() {
2704 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2705 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2706 let config = UserConfig::default();
2707 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
2708 let scorer = ln_test_utils::TestScorer::new();
2709 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2710 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2712 // A route to node#2 via two paths.
2713 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2714 // Thus, they can't send 60 without overpaying.
2715 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2716 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2717 short_channel_id: 2,
2720 cltv_expiry_delta: 0,
2721 htlc_minimum_msat: 35_000,
2722 htlc_maximum_msat: 40_000,
2724 fee_proportional_millionths: 0,
2725 excess_data: Vec::new()
2727 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2728 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2729 short_channel_id: 12,
2732 cltv_expiry_delta: 0,
2733 htlc_minimum_msat: 35_000,
2734 htlc_maximum_msat: 40_000,
2736 fee_proportional_millionths: 0,
2737 excess_data: Vec::new()
2741 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2742 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2743 short_channel_id: 13,
2746 cltv_expiry_delta: 0,
2747 htlc_minimum_msat: 0,
2748 htlc_maximum_msat: MAX_VALUE_MSAT,
2750 fee_proportional_millionths: 0,
2751 excess_data: Vec::new()
2753 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2754 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2755 short_channel_id: 4,
2758 cltv_expiry_delta: 0,
2759 htlc_minimum_msat: 0,
2760 htlc_maximum_msat: MAX_VALUE_MSAT,
2762 fee_proportional_millionths: 0,
2763 excess_data: Vec::new()
2766 // Disable other paths
2767 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2768 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2769 short_channel_id: 1,
2771 flags: 2, // to disable
2772 cltv_expiry_delta: 0,
2773 htlc_minimum_msat: 0,
2774 htlc_maximum_msat: MAX_VALUE_MSAT,
2776 fee_proportional_millionths: 0,
2777 excess_data: Vec::new()
2780 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2781 // Overpay fees to hit htlc_minimum_msat.
2782 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
2783 // TODO: this could be better balanced to overpay 10k and not 15k.
2784 assert_eq!(overpaid_fees, 15_000);
2786 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2787 // while taking even more fee to match htlc_minimum_msat.
2788 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2789 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2790 short_channel_id: 12,
2793 cltv_expiry_delta: 0,
2794 htlc_minimum_msat: 65_000,
2795 htlc_maximum_msat: 80_000,
2797 fee_proportional_millionths: 0,
2798 excess_data: Vec::new()
2800 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2801 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2802 short_channel_id: 2,
2805 cltv_expiry_delta: 0,
2806 htlc_minimum_msat: 0,
2807 htlc_maximum_msat: MAX_VALUE_MSAT,
2809 fee_proportional_millionths: 0,
2810 excess_data: Vec::new()
2812 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2813 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2814 short_channel_id: 4,
2817 cltv_expiry_delta: 0,
2818 htlc_minimum_msat: 0,
2819 htlc_maximum_msat: MAX_VALUE_MSAT,
2821 fee_proportional_millionths: 100_000,
2822 excess_data: Vec::new()
2825 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2826 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2827 assert_eq!(route.paths.len(), 1);
2828 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
2829 let fees = route.paths[0].hops[0].fee_msat;
2830 assert_eq!(fees, 5_000);
2832 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2833 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2834 // the other channel.
2835 assert_eq!(route.paths.len(), 1);
2836 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2837 let fees = route.paths[0].hops[0].fee_msat;
2838 assert_eq!(fees, 5_000);
2842 fn disable_channels_test() {
2843 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2844 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2845 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2846 let scorer = ln_test_utils::TestScorer::new();
2847 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2848 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2850 // // Disable channels 4 and 12 by flags=2
2851 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2852 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2853 short_channel_id: 4,
2855 flags: 2, // to disable
2856 cltv_expiry_delta: 0,
2857 htlc_minimum_msat: 0,
2858 htlc_maximum_msat: MAX_VALUE_MSAT,
2860 fee_proportional_millionths: 0,
2861 excess_data: Vec::new()
2863 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2864 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2865 short_channel_id: 12,
2867 flags: 2, // to disable
2868 cltv_expiry_delta: 0,
2869 htlc_minimum_msat: 0,
2870 htlc_maximum_msat: MAX_VALUE_MSAT,
2872 fee_proportional_millionths: 0,
2873 excess_data: Vec::new()
2876 // If all the channels require some features we don't understand, route should fail
2877 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2878 assert_eq!(err, "Failed to find a path to the given destination");
2879 } else { panic!(); }
2881 // If we specify a channel to node7, that overrides our local channel view and that gets used
2882 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2883 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2884 assert_eq!(route.paths[0].hops.len(), 2);
2886 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
2887 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
2888 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
2889 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
2890 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2891 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2893 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2894 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
2895 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2896 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2897 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2898 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
2902 fn disable_node_test() {
2903 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2904 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2905 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2906 let scorer = ln_test_utils::TestScorer::new();
2907 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2908 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2910 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2911 let mut unknown_features = NodeFeatures::empty();
2912 unknown_features.set_unknown_feature_required();
2913 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2914 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2915 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2917 // If all nodes require some features we don't understand, route should fail
2918 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2919 assert_eq!(err, "Failed to find a path to the given destination");
2920 } else { panic!(); }
2922 // If we specify a channel to node7, that overrides our local channel view and that gets used
2923 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2924 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2925 assert_eq!(route.paths[0].hops.len(), 2);
2927 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
2928 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
2929 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
2930 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
2931 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2932 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2934 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2935 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
2936 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2937 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2938 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2939 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
2941 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2942 // naively) assume that the user checked the feature bits on the invoice, which override
2943 // the node_announcement.
2947 fn our_chans_test() {
2948 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2949 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2950 let scorer = ln_test_utils::TestScorer::new();
2951 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2952 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2954 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2955 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
2956 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2957 assert_eq!(route.paths[0].hops.len(), 3);
2959 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2960 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2961 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
2962 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2963 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2964 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2966 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2967 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2968 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2969 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
2970 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2971 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2973 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
2974 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
2975 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
2976 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
2977 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
2978 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
2980 // If we specify a channel to node7, that overrides our local channel view and that gets used
2981 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2982 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2983 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2984 assert_eq!(route.paths[0].hops.len(), 2);
2986 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
2987 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
2988 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
2989 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
2990 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
2991 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2993 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2994 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
2995 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2996 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2997 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2998 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3001 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3002 let zero_fees = RoutingFees {
3004 proportional_millionths: 0,
3006 vec![RouteHint(vec![RouteHintHop {
3007 src_node_id: nodes[3],
3008 short_channel_id: 8,
3010 cltv_expiry_delta: (8 << 4) | 1,
3011 htlc_minimum_msat: None,
3012 htlc_maximum_msat: None,
3014 ]), RouteHint(vec![RouteHintHop {
3015 src_node_id: nodes[4],
3016 short_channel_id: 9,
3019 proportional_millionths: 0,
3021 cltv_expiry_delta: (9 << 4) | 1,
3022 htlc_minimum_msat: None,
3023 htlc_maximum_msat: None,
3024 }]), RouteHint(vec![RouteHintHop {
3025 src_node_id: nodes[5],
3026 short_channel_id: 10,
3028 cltv_expiry_delta: (10 << 4) | 1,
3029 htlc_minimum_msat: None,
3030 htlc_maximum_msat: None,
3034 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3035 let zero_fees = RoutingFees {
3037 proportional_millionths: 0,
3039 vec![RouteHint(vec![RouteHintHop {
3040 src_node_id: nodes[2],
3041 short_channel_id: 5,
3044 proportional_millionths: 0,
3046 cltv_expiry_delta: (5 << 4) | 1,
3047 htlc_minimum_msat: None,
3048 htlc_maximum_msat: None,
3050 src_node_id: nodes[3],
3051 short_channel_id: 8,
3053 cltv_expiry_delta: (8 << 4) | 1,
3054 htlc_minimum_msat: None,
3055 htlc_maximum_msat: None,
3057 ]), RouteHint(vec![RouteHintHop {
3058 src_node_id: nodes[4],
3059 short_channel_id: 9,
3062 proportional_millionths: 0,
3064 cltv_expiry_delta: (9 << 4) | 1,
3065 htlc_minimum_msat: None,
3066 htlc_maximum_msat: None,
3067 }]), RouteHint(vec![RouteHintHop {
3068 src_node_id: nodes[5],
3069 short_channel_id: 10,
3071 cltv_expiry_delta: (10 << 4) | 1,
3072 htlc_minimum_msat: None,
3073 htlc_maximum_msat: None,
3078 fn partial_route_hint_test() {
3079 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3080 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3081 let scorer = ln_test_utils::TestScorer::new();
3082 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3083 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3085 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3086 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3087 // RouteHint may be partially used by the algo to build the best path.
3089 // First check that last hop can't have its source as the payee.
3090 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3091 src_node_id: nodes[6],
3092 short_channel_id: 8,
3095 proportional_millionths: 0,
3097 cltv_expiry_delta: (8 << 4) | 1,
3098 htlc_minimum_msat: None,
3099 htlc_maximum_msat: None,
3102 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3103 invalid_last_hops.push(invalid_last_hop);
3105 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(invalid_last_hops).unwrap();
3106 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3107 assert_eq!(err, "Route hint cannot have the payee as the source.");
3108 } else { panic!(); }
3111 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3112 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3113 assert_eq!(route.paths[0].hops.len(), 5);
3115 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3116 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3117 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3118 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3119 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3120 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3122 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3123 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3124 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3125 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3126 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3127 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3129 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3130 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3131 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3132 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3133 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3134 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3136 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3137 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3138 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3139 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3140 // If we have a peer in the node map, we'll use their features here since we don't have
3141 // a way of figuring out their features from the invoice:
3142 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3143 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3145 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3146 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3147 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3148 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3149 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3150 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3153 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3154 let zero_fees = RoutingFees {
3156 proportional_millionths: 0,
3158 vec![RouteHint(vec![RouteHintHop {
3159 src_node_id: nodes[3],
3160 short_channel_id: 8,
3162 cltv_expiry_delta: (8 << 4) | 1,
3163 htlc_minimum_msat: None,
3164 htlc_maximum_msat: None,
3165 }]), RouteHint(vec![
3167 ]), RouteHint(vec![RouteHintHop {
3168 src_node_id: nodes[5],
3169 short_channel_id: 10,
3171 cltv_expiry_delta: (10 << 4) | 1,
3172 htlc_minimum_msat: None,
3173 htlc_maximum_msat: None,
3178 fn ignores_empty_last_hops_test() {
3179 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3180 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3181 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3182 let scorer = ln_test_utils::TestScorer::new();
3183 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3184 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3186 // Test handling of an empty RouteHint passed in Invoice.
3188 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3189 assert_eq!(route.paths[0].hops.len(), 5);
3191 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3192 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3193 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3194 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3195 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3196 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3198 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3199 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3200 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3201 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3202 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3203 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3205 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3206 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3207 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3208 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3209 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3210 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3212 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3213 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3214 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3215 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3216 // If we have a peer in the node map, we'll use their features here since we don't have
3217 // a way of figuring out their features from the invoice:
3218 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3219 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3221 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3222 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3223 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3224 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3225 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3226 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3229 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3231 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3232 let zero_fees = RoutingFees {
3234 proportional_millionths: 0,
3236 vec![RouteHint(vec![RouteHintHop {
3237 src_node_id: hint_hops[0],
3238 short_channel_id: 0xff00,
3241 proportional_millionths: 0,
3243 cltv_expiry_delta: (5 << 4) | 1,
3244 htlc_minimum_msat: None,
3245 htlc_maximum_msat: None,
3247 src_node_id: hint_hops[1],
3248 short_channel_id: 0xff01,
3250 cltv_expiry_delta: (8 << 4) | 1,
3251 htlc_minimum_msat: None,
3252 htlc_maximum_msat: None,
3257 fn multi_hint_last_hops_test() {
3258 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3259 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3260 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3261 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3262 let scorer = ln_test_utils::TestScorer::new();
3263 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3264 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3265 // Test through channels 2, 3, 0xff00, 0xff01.
3266 // Test shows that multiple hop hints are considered.
3268 // Disabling channels 6 & 7 by flags=2
3269 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3270 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3271 short_channel_id: 6,
3273 flags: 2, // to disable
3274 cltv_expiry_delta: 0,
3275 htlc_minimum_msat: 0,
3276 htlc_maximum_msat: MAX_VALUE_MSAT,
3278 fee_proportional_millionths: 0,
3279 excess_data: Vec::new()
3281 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3282 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3283 short_channel_id: 7,
3285 flags: 2, // to disable
3286 cltv_expiry_delta: 0,
3287 htlc_minimum_msat: 0,
3288 htlc_maximum_msat: MAX_VALUE_MSAT,
3290 fee_proportional_millionths: 0,
3291 excess_data: Vec::new()
3294 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3295 assert_eq!(route.paths[0].hops.len(), 4);
3297 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3298 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3299 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3300 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3301 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3302 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3304 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3305 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3306 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3307 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3308 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3309 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3311 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3312 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3313 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3314 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3315 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3316 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3318 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3319 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3320 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3321 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3322 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3323 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3327 fn private_multi_hint_last_hops_test() {
3328 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3329 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3331 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3332 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3334 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3335 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3336 let scorer = ln_test_utils::TestScorer::new();
3337 // Test through channels 2, 3, 0xff00, 0xff01.
3338 // Test shows that multiple hop hints are considered.
3340 // Disabling channels 6 & 7 by flags=2
3341 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3342 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3343 short_channel_id: 6,
3345 flags: 2, // to disable
3346 cltv_expiry_delta: 0,
3347 htlc_minimum_msat: 0,
3348 htlc_maximum_msat: MAX_VALUE_MSAT,
3350 fee_proportional_millionths: 0,
3351 excess_data: Vec::new()
3353 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3354 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3355 short_channel_id: 7,
3357 flags: 2, // to disable
3358 cltv_expiry_delta: 0,
3359 htlc_minimum_msat: 0,
3360 htlc_maximum_msat: MAX_VALUE_MSAT,
3362 fee_proportional_millionths: 0,
3363 excess_data: Vec::new()
3366 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &[42u8; 32]).unwrap();
3367 assert_eq!(route.paths[0].hops.len(), 4);
3369 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3370 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3371 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3372 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3373 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3374 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3376 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3377 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3378 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3379 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3380 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3381 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3383 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3384 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3385 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3386 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3387 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3388 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3390 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3391 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3392 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3393 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3394 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3395 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3398 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3399 let zero_fees = RoutingFees {
3401 proportional_millionths: 0,
3403 vec![RouteHint(vec![RouteHintHop {
3404 src_node_id: nodes[4],
3405 short_channel_id: 11,
3407 cltv_expiry_delta: (11 << 4) | 1,
3408 htlc_minimum_msat: None,
3409 htlc_maximum_msat: None,
3411 src_node_id: nodes[3],
3412 short_channel_id: 8,
3414 cltv_expiry_delta: (8 << 4) | 1,
3415 htlc_minimum_msat: None,
3416 htlc_maximum_msat: None,
3417 }]), RouteHint(vec![RouteHintHop {
3418 src_node_id: nodes[4],
3419 short_channel_id: 9,
3422 proportional_millionths: 0,
3424 cltv_expiry_delta: (9 << 4) | 1,
3425 htlc_minimum_msat: None,
3426 htlc_maximum_msat: None,
3427 }]), RouteHint(vec![RouteHintHop {
3428 src_node_id: nodes[5],
3429 short_channel_id: 10,
3431 cltv_expiry_delta: (10 << 4) | 1,
3432 htlc_minimum_msat: None,
3433 htlc_maximum_msat: None,
3438 fn last_hops_with_public_channel_test() {
3439 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3440 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3441 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3442 let scorer = ln_test_utils::TestScorer::new();
3443 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3444 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3445 // This test shows that public routes can be present in the invoice
3446 // which would be handled in the same manner.
3448 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3449 assert_eq!(route.paths[0].hops.len(), 5);
3451 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3452 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3453 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3454 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3455 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3456 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3458 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3459 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3460 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3461 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3462 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3463 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3465 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3466 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3467 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3468 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3469 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3470 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3472 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3473 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3474 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3475 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3476 // If we have a peer in the node map, we'll use their features here since we don't have
3477 // a way of figuring out their features from the invoice:
3478 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3479 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3481 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3482 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3483 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3484 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3485 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3486 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3490 fn our_chans_last_hop_connect_test() {
3491 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3492 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3493 let scorer = ln_test_utils::TestScorer::new();
3494 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3495 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3497 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3498 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3499 let mut last_hops = last_hops(&nodes);
3500 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3501 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3502 assert_eq!(route.paths[0].hops.len(), 2);
3504 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3505 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3506 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3507 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3508 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3509 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3511 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3512 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3513 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3514 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3515 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3516 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3518 last_hops[0].0[0].fees.base_msat = 1000;
3520 // Revert to via 6 as the fee on 8 goes up
3521 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops).unwrap();
3522 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3523 assert_eq!(route.paths[0].hops.len(), 4);
3525 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3526 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3527 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3528 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3529 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3530 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3532 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3533 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3534 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3535 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3536 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3537 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3539 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3540 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3541 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3542 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3543 // If we have a peer in the node map, we'll use their features here since we don't have
3544 // a way of figuring out their features from the invoice:
3545 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3546 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3548 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3549 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3550 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3551 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3552 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3553 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3555 // ...but still use 8 for larger payments as 6 has a variable feerate
3556 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3557 assert_eq!(route.paths[0].hops.len(), 5);
3559 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3560 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3561 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3562 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3563 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3564 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3566 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3567 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3568 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3569 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3570 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3571 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3573 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3574 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3575 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3576 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3577 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3578 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3580 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3581 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3582 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
3583 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3584 // If we have a peer in the node map, we'll use their features here since we don't have
3585 // a way of figuring out their features from the invoice:
3586 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3587 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3589 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3590 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3591 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
3592 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3593 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3594 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3597 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> {
3598 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3599 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3600 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3602 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3603 let last_hops = RouteHint(vec![RouteHintHop {
3604 src_node_id: middle_node_id,
3605 short_channel_id: 8,
3608 proportional_millionths: last_hop_fee_prop,
3610 cltv_expiry_delta: (8 << 4) | 1,
3611 htlc_minimum_msat: None,
3612 htlc_maximum_msat: last_hop_htlc_max,
3614 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
3615 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3616 let scorer = ln_test_utils::TestScorer::new();
3617 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3618 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3619 let logger = ln_test_utils::TestLogger::new();
3620 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
3621 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3622 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, &logger, &scorer, &(), &random_seed_bytes);
3627 fn unannounced_path_test() {
3628 // We should be able to send a payment to a destination without any help of a routing graph
3629 // if we have a channel with a common counterparty that appears in the first and last hop
3631 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3633 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3634 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3635 assert_eq!(route.paths[0].hops.len(), 2);
3637 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
3638 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3639 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
3640 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3641 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
3642 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3644 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
3645 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3646 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
3647 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3648 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3649 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3653 fn overflow_unannounced_path_test_liquidity_underflow() {
3654 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3655 // the last-hop had a fee which overflowed a u64, we'd panic.
3656 // This was due to us adding the first-hop from us unconditionally, causing us to think
3657 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3658 // In this test, we previously hit a subtraction underflow due to having less available
3659 // liquidity at the last hop than 0.
3660 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());
3664 fn overflow_unannounced_path_test_feerate_overflow() {
3665 // This tests for the same case as above, except instead of hitting a subtraction
3666 // underflow, we hit a case where the fee charged at a hop overflowed.
3667 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());
3671 fn available_amount_while_routing_test() {
3672 // Tests whether we choose the correct available channel amount while routing.
3674 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3675 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3676 let scorer = ln_test_utils::TestScorer::new();
3677 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3678 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3679 let config = UserConfig::default();
3680 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3682 // We will use a simple single-path route from
3683 // our node to node2 via node0: channels {1, 3}.
3685 // First disable all other paths.
3686 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3687 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3688 short_channel_id: 2,
3691 cltv_expiry_delta: 0,
3692 htlc_minimum_msat: 0,
3693 htlc_maximum_msat: 100_000,
3695 fee_proportional_millionths: 0,
3696 excess_data: Vec::new()
3698 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3699 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3700 short_channel_id: 12,
3703 cltv_expiry_delta: 0,
3704 htlc_minimum_msat: 0,
3705 htlc_maximum_msat: 100_000,
3707 fee_proportional_millionths: 0,
3708 excess_data: Vec::new()
3711 // Make the first channel (#1) very permissive,
3712 // and we will be testing all limits on the second channel.
3713 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3714 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3715 short_channel_id: 1,
3718 cltv_expiry_delta: 0,
3719 htlc_minimum_msat: 0,
3720 htlc_maximum_msat: 1_000_000_000,
3722 fee_proportional_millionths: 0,
3723 excess_data: Vec::new()
3726 // First, let's see if routing works if we have absolutely no idea about the available amount.
3727 // In this case, it should be set to 250_000 sats.
3728 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3729 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3730 short_channel_id: 3,
3733 cltv_expiry_delta: 0,
3734 htlc_minimum_msat: 0,
3735 htlc_maximum_msat: 250_000_000,
3737 fee_proportional_millionths: 0,
3738 excess_data: Vec::new()
3742 // Attempt to route more than available results in a failure.
3743 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3744 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3745 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3746 } else { panic!(); }
3750 // Now, attempt to route an exact amount we have should be fine.
3751 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000_000, Arc::clone(&logger), &scorer, &(),&random_seed_bytes).unwrap();
3752 assert_eq!(route.paths.len(), 1);
3753 let path = route.paths.last().unwrap();
3754 assert_eq!(path.hops.len(), 2);
3755 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3756 assert_eq!(path.final_value_msat(), 250_000_000);
3759 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3760 // Disable channel #1 and use another first hop.
3761 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3762 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3763 short_channel_id: 1,
3766 cltv_expiry_delta: 0,
3767 htlc_minimum_msat: 0,
3768 htlc_maximum_msat: 1_000_000_000,
3770 fee_proportional_millionths: 0,
3771 excess_data: Vec::new()
3774 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3775 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3778 // Attempt to route more than available results in a failure.
3779 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3780 &our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3781 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3782 } else { panic!(); }
3786 // Now, attempt to route an exact amount we have should be fine.
3787 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3788 assert_eq!(route.paths.len(), 1);
3789 let path = route.paths.last().unwrap();
3790 assert_eq!(path.hops.len(), 2);
3791 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3792 assert_eq!(path.final_value_msat(), 200_000_000);
3795 // Enable channel #1 back.
3796 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3797 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3798 short_channel_id: 1,
3801 cltv_expiry_delta: 0,
3802 htlc_minimum_msat: 0,
3803 htlc_maximum_msat: 1_000_000_000,
3805 fee_proportional_millionths: 0,
3806 excess_data: Vec::new()
3810 // Now let's see if routing works if we know only htlc_maximum_msat.
3811 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3812 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3813 short_channel_id: 3,
3816 cltv_expiry_delta: 0,
3817 htlc_minimum_msat: 0,
3818 htlc_maximum_msat: 15_000,
3820 fee_proportional_millionths: 0,
3821 excess_data: Vec::new()
3825 // Attempt to route more than available results in a failure.
3826 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3827 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3828 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3829 } else { panic!(); }
3833 // Now, attempt to route an exact amount we have should be fine.
3834 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3835 assert_eq!(route.paths.len(), 1);
3836 let path = route.paths.last().unwrap();
3837 assert_eq!(path.hops.len(), 2);
3838 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3839 assert_eq!(path.final_value_msat(), 15_000);
3842 // Now let's see if routing works if we know only capacity from the UTXO.
3844 // We can't change UTXO capacity on the fly, so we'll disable
3845 // the existing channel and add another one with the capacity we need.
3846 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3848 short_channel_id: 3,
3851 cltv_expiry_delta: 0,
3852 htlc_minimum_msat: 0,
3853 htlc_maximum_msat: MAX_VALUE_MSAT,
3855 fee_proportional_millionths: 0,
3856 excess_data: Vec::new()
3859 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3860 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3861 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3862 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3863 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3865 *chain_monitor.utxo_ret.lock().unwrap() =
3866 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
3867 gossip_sync.add_utxo_lookup(Some(chain_monitor));
3869 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3870 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3871 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3872 short_channel_id: 333,
3875 cltv_expiry_delta: (3 << 4) | 1,
3876 htlc_minimum_msat: 0,
3877 htlc_maximum_msat: 15_000,
3879 fee_proportional_millionths: 0,
3880 excess_data: Vec::new()
3882 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3883 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3884 short_channel_id: 333,
3887 cltv_expiry_delta: (3 << 4) | 2,
3888 htlc_minimum_msat: 0,
3889 htlc_maximum_msat: 15_000,
3891 fee_proportional_millionths: 0,
3892 excess_data: Vec::new()
3896 // Attempt to route more than available results in a failure.
3897 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3898 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3899 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3900 } else { panic!(); }
3904 // Now, attempt to route an exact amount we have should be fine.
3905 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3906 assert_eq!(route.paths.len(), 1);
3907 let path = route.paths.last().unwrap();
3908 assert_eq!(path.hops.len(), 2);
3909 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3910 assert_eq!(path.final_value_msat(), 15_000);
3913 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3914 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3915 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3916 short_channel_id: 333,
3919 cltv_expiry_delta: 0,
3920 htlc_minimum_msat: 0,
3921 htlc_maximum_msat: 10_000,
3923 fee_proportional_millionths: 0,
3924 excess_data: Vec::new()
3928 // Attempt to route more than available results in a failure.
3929 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3930 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3931 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3932 } else { panic!(); }
3936 // Now, attempt to route an exact amount we have should be fine.
3937 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3938 assert_eq!(route.paths.len(), 1);
3939 let path = route.paths.last().unwrap();
3940 assert_eq!(path.hops.len(), 2);
3941 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3942 assert_eq!(path.final_value_msat(), 10_000);
3947 fn available_liquidity_last_hop_test() {
3948 // Check that available liquidity properly limits the path even when only
3949 // one of the latter hops is limited.
3950 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3951 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3952 let scorer = ln_test_utils::TestScorer::new();
3953 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3954 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3955 let config = UserConfig::default();
3956 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3958 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3959 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3960 // Total capacity: 50 sats.
3962 // Disable other potential paths.
3963 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3964 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3965 short_channel_id: 2,
3968 cltv_expiry_delta: 0,
3969 htlc_minimum_msat: 0,
3970 htlc_maximum_msat: 100_000,
3972 fee_proportional_millionths: 0,
3973 excess_data: Vec::new()
3975 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3976 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3977 short_channel_id: 7,
3980 cltv_expiry_delta: 0,
3981 htlc_minimum_msat: 0,
3982 htlc_maximum_msat: 100_000,
3984 fee_proportional_millionths: 0,
3985 excess_data: Vec::new()
3990 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3991 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3992 short_channel_id: 12,
3995 cltv_expiry_delta: 0,
3996 htlc_minimum_msat: 0,
3997 htlc_maximum_msat: 100_000,
3999 fee_proportional_millionths: 0,
4000 excess_data: Vec::new()
4002 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4003 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4004 short_channel_id: 13,
4007 cltv_expiry_delta: 0,
4008 htlc_minimum_msat: 0,
4009 htlc_maximum_msat: 100_000,
4011 fee_proportional_millionths: 0,
4012 excess_data: Vec::new()
4015 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4016 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4017 short_channel_id: 6,
4020 cltv_expiry_delta: 0,
4021 htlc_minimum_msat: 0,
4022 htlc_maximum_msat: 50_000,
4024 fee_proportional_millionths: 0,
4025 excess_data: Vec::new()
4027 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4028 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4029 short_channel_id: 11,
4032 cltv_expiry_delta: 0,
4033 htlc_minimum_msat: 0,
4034 htlc_maximum_msat: 100_000,
4036 fee_proportional_millionths: 0,
4037 excess_data: Vec::new()
4040 // Attempt to route more than available results in a failure.
4041 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4042 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4043 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4044 } else { panic!(); }
4048 // Now, attempt to route 49 sats (just a bit below the capacity).
4049 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4050 assert_eq!(route.paths.len(), 1);
4051 let mut total_amount_paid_msat = 0;
4052 for path in &route.paths {
4053 assert_eq!(path.hops.len(), 4);
4054 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4055 total_amount_paid_msat += path.final_value_msat();
4057 assert_eq!(total_amount_paid_msat, 49_000);
4061 // Attempt to route an exact amount is also fine
4062 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4063 assert_eq!(route.paths.len(), 1);
4064 let mut total_amount_paid_msat = 0;
4065 for path in &route.paths {
4066 assert_eq!(path.hops.len(), 4);
4067 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4068 total_amount_paid_msat += path.final_value_msat();
4070 assert_eq!(total_amount_paid_msat, 50_000);
4075 fn ignore_fee_first_hop_test() {
4076 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4077 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4078 let scorer = ln_test_utils::TestScorer::new();
4079 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4080 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4081 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4083 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4084 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4085 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4086 short_channel_id: 1,
4089 cltv_expiry_delta: 0,
4090 htlc_minimum_msat: 0,
4091 htlc_maximum_msat: 100_000,
4092 fee_base_msat: 1_000_000,
4093 fee_proportional_millionths: 0,
4094 excess_data: Vec::new()
4096 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4097 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4098 short_channel_id: 3,
4101 cltv_expiry_delta: 0,
4102 htlc_minimum_msat: 0,
4103 htlc_maximum_msat: 50_000,
4105 fee_proportional_millionths: 0,
4106 excess_data: Vec::new()
4110 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4111 assert_eq!(route.paths.len(), 1);
4112 let mut total_amount_paid_msat = 0;
4113 for path in &route.paths {
4114 assert_eq!(path.hops.len(), 2);
4115 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4116 total_amount_paid_msat += path.final_value_msat();
4118 assert_eq!(total_amount_paid_msat, 50_000);
4123 fn simple_mpp_route_test() {
4124 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4125 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4126 let scorer = ln_test_utils::TestScorer::new();
4127 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4128 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4129 let config = UserConfig::default();
4130 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4131 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4133 // We need a route consisting of 3 paths:
4134 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4135 // To achieve this, the amount being transferred should be around
4136 // the total capacity of these 3 paths.
4138 // First, we set limits on these (previously unlimited) channels.
4139 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4141 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4142 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4144 short_channel_id: 1,
4147 cltv_expiry_delta: 0,
4148 htlc_minimum_msat: 0,
4149 htlc_maximum_msat: 100_000,
4151 fee_proportional_millionths: 0,
4152 excess_data: Vec::new()
4154 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4156 short_channel_id: 3,
4159 cltv_expiry_delta: 0,
4160 htlc_minimum_msat: 0,
4161 htlc_maximum_msat: 50_000,
4163 fee_proportional_millionths: 0,
4164 excess_data: Vec::new()
4167 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4168 // (total limit 60).
4169 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4170 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4171 short_channel_id: 12,
4174 cltv_expiry_delta: 0,
4175 htlc_minimum_msat: 0,
4176 htlc_maximum_msat: 60_000,
4178 fee_proportional_millionths: 0,
4179 excess_data: Vec::new()
4181 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4182 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4183 short_channel_id: 13,
4186 cltv_expiry_delta: 0,
4187 htlc_minimum_msat: 0,
4188 htlc_maximum_msat: 60_000,
4190 fee_proportional_millionths: 0,
4191 excess_data: Vec::new()
4194 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4195 // (total capacity 180 sats).
4196 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4197 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4198 short_channel_id: 2,
4201 cltv_expiry_delta: 0,
4202 htlc_minimum_msat: 0,
4203 htlc_maximum_msat: 200_000,
4205 fee_proportional_millionths: 0,
4206 excess_data: Vec::new()
4208 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4209 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4210 short_channel_id: 4,
4213 cltv_expiry_delta: 0,
4214 htlc_minimum_msat: 0,
4215 htlc_maximum_msat: 180_000,
4217 fee_proportional_millionths: 0,
4218 excess_data: Vec::new()
4222 // Attempt to route more than available results in a failure.
4223 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4224 &our_id, &payment_params, &network_graph.read_only(), None, 300_000,
4225 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4226 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4227 } else { panic!(); }
4231 // Attempt to route while setting max_path_count to 0 results in a failure.
4232 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4233 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4234 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100,
4235 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4236 assert_eq!(err, "Can't find a route with no paths allowed.");
4237 } else { panic!(); }
4241 // Attempt to route while setting max_path_count to 3 results in a failure.
4242 // This is the case because the minimal_value_contribution_msat would require each path
4243 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4244 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4245 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4246 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000,
4247 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4248 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4249 } else { panic!(); }
4253 // Now, attempt to route 250 sats (just a bit below the capacity).
4254 // Our algorithm should provide us with these 3 paths.
4255 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4256 250_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4257 assert_eq!(route.paths.len(), 3);
4258 let mut total_amount_paid_msat = 0;
4259 for path in &route.paths {
4260 assert_eq!(path.hops.len(), 2);
4261 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4262 total_amount_paid_msat += path.final_value_msat();
4264 assert_eq!(total_amount_paid_msat, 250_000);
4268 // Attempt to route an exact amount is also fine
4269 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4270 290_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4271 assert_eq!(route.paths.len(), 3);
4272 let mut total_amount_paid_msat = 0;
4273 for path in &route.paths {
4274 assert_eq!(path.hops.len(), 2);
4275 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4276 total_amount_paid_msat += path.final_value_msat();
4278 assert_eq!(total_amount_paid_msat, 290_000);
4283 fn long_mpp_route_test() {
4284 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4285 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4286 let scorer = ln_test_utils::TestScorer::new();
4287 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4288 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4289 let config = UserConfig::default();
4290 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4292 // We need a route consisting of 3 paths:
4293 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4294 // Note that these paths overlap (channels 5, 12, 13).
4295 // We will route 300 sats.
4296 // Each path will have 100 sats capacity, those channels which
4297 // are used twice will have 200 sats capacity.
4299 // Disable other potential paths.
4300 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4301 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4302 short_channel_id: 2,
4305 cltv_expiry_delta: 0,
4306 htlc_minimum_msat: 0,
4307 htlc_maximum_msat: 100_000,
4309 fee_proportional_millionths: 0,
4310 excess_data: Vec::new()
4312 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4313 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4314 short_channel_id: 7,
4317 cltv_expiry_delta: 0,
4318 htlc_minimum_msat: 0,
4319 htlc_maximum_msat: 100_000,
4321 fee_proportional_millionths: 0,
4322 excess_data: Vec::new()
4325 // Path via {node0, node2} is channels {1, 3, 5}.
4326 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4327 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4328 short_channel_id: 1,
4331 cltv_expiry_delta: 0,
4332 htlc_minimum_msat: 0,
4333 htlc_maximum_msat: 100_000,
4335 fee_proportional_millionths: 0,
4336 excess_data: Vec::new()
4338 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4339 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4340 short_channel_id: 3,
4343 cltv_expiry_delta: 0,
4344 htlc_minimum_msat: 0,
4345 htlc_maximum_msat: 100_000,
4347 fee_proportional_millionths: 0,
4348 excess_data: Vec::new()
4351 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4352 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4353 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4354 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4355 short_channel_id: 5,
4358 cltv_expiry_delta: 0,
4359 htlc_minimum_msat: 0,
4360 htlc_maximum_msat: 200_000,
4362 fee_proportional_millionths: 0,
4363 excess_data: Vec::new()
4366 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4367 // Add 100 sats to the capacities of {12, 13}, because these channels
4368 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4369 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4370 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4371 short_channel_id: 12,
4374 cltv_expiry_delta: 0,
4375 htlc_minimum_msat: 0,
4376 htlc_maximum_msat: 200_000,
4378 fee_proportional_millionths: 0,
4379 excess_data: Vec::new()
4381 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4382 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4383 short_channel_id: 13,
4386 cltv_expiry_delta: 0,
4387 htlc_minimum_msat: 0,
4388 htlc_maximum_msat: 200_000,
4390 fee_proportional_millionths: 0,
4391 excess_data: Vec::new()
4394 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4395 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4396 short_channel_id: 6,
4399 cltv_expiry_delta: 0,
4400 htlc_minimum_msat: 0,
4401 htlc_maximum_msat: 100_000,
4403 fee_proportional_millionths: 0,
4404 excess_data: Vec::new()
4406 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4407 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4408 short_channel_id: 11,
4411 cltv_expiry_delta: 0,
4412 htlc_minimum_msat: 0,
4413 htlc_maximum_msat: 100_000,
4415 fee_proportional_millionths: 0,
4416 excess_data: Vec::new()
4419 // Path via {node7, node2} is channels {12, 13, 5}.
4420 // We already limited them to 200 sats (they are used twice for 100 sats).
4421 // Nothing to do here.
4424 // Attempt to route more than available results in a failure.
4425 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4426 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4427 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4428 } else { panic!(); }
4432 // Now, attempt to route 300 sats (exact amount we can route).
4433 // Our algorithm should provide us with these 3 paths, 100 sats each.
4434 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4435 assert_eq!(route.paths.len(), 3);
4437 let mut total_amount_paid_msat = 0;
4438 for path in &route.paths {
4439 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4440 total_amount_paid_msat += path.final_value_msat();
4442 assert_eq!(total_amount_paid_msat, 300_000);
4448 fn mpp_cheaper_route_test() {
4449 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4450 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4451 let scorer = ln_test_utils::TestScorer::new();
4452 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4453 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4454 let config = UserConfig::default();
4455 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4457 // This test checks that if we have two cheaper paths and one more expensive path,
4458 // so that liquidity-wise any 2 of 3 combination is sufficient,
4459 // two cheaper paths will be taken.
4460 // These paths have equal available liquidity.
4462 // We need a combination of 3 paths:
4463 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4464 // Note that these paths overlap (channels 5, 12, 13).
4465 // Each path will have 100 sats capacity, those channels which
4466 // are used twice will have 200 sats capacity.
4468 // Disable other potential paths.
4469 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4471 short_channel_id: 2,
4474 cltv_expiry_delta: 0,
4475 htlc_minimum_msat: 0,
4476 htlc_maximum_msat: 100_000,
4478 fee_proportional_millionths: 0,
4479 excess_data: Vec::new()
4481 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4482 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4483 short_channel_id: 7,
4486 cltv_expiry_delta: 0,
4487 htlc_minimum_msat: 0,
4488 htlc_maximum_msat: 100_000,
4490 fee_proportional_millionths: 0,
4491 excess_data: Vec::new()
4494 // Path via {node0, node2} is channels {1, 3, 5}.
4495 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4496 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4497 short_channel_id: 1,
4500 cltv_expiry_delta: 0,
4501 htlc_minimum_msat: 0,
4502 htlc_maximum_msat: 100_000,
4504 fee_proportional_millionths: 0,
4505 excess_data: Vec::new()
4507 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4508 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4509 short_channel_id: 3,
4512 cltv_expiry_delta: 0,
4513 htlc_minimum_msat: 0,
4514 htlc_maximum_msat: 100_000,
4516 fee_proportional_millionths: 0,
4517 excess_data: Vec::new()
4520 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4521 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4522 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4523 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4524 short_channel_id: 5,
4527 cltv_expiry_delta: 0,
4528 htlc_minimum_msat: 0,
4529 htlc_maximum_msat: 200_000,
4531 fee_proportional_millionths: 0,
4532 excess_data: Vec::new()
4535 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4536 // Add 100 sats to the capacities of {12, 13}, because these channels
4537 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4538 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4539 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4540 short_channel_id: 12,
4543 cltv_expiry_delta: 0,
4544 htlc_minimum_msat: 0,
4545 htlc_maximum_msat: 200_000,
4547 fee_proportional_millionths: 0,
4548 excess_data: Vec::new()
4550 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4551 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4552 short_channel_id: 13,
4555 cltv_expiry_delta: 0,
4556 htlc_minimum_msat: 0,
4557 htlc_maximum_msat: 200_000,
4559 fee_proportional_millionths: 0,
4560 excess_data: Vec::new()
4563 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4565 short_channel_id: 6,
4568 cltv_expiry_delta: 0,
4569 htlc_minimum_msat: 0,
4570 htlc_maximum_msat: 100_000,
4571 fee_base_msat: 1_000,
4572 fee_proportional_millionths: 0,
4573 excess_data: Vec::new()
4575 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4577 short_channel_id: 11,
4580 cltv_expiry_delta: 0,
4581 htlc_minimum_msat: 0,
4582 htlc_maximum_msat: 100_000,
4584 fee_proportional_millionths: 0,
4585 excess_data: Vec::new()
4588 // Path via {node7, node2} is channels {12, 13, 5}.
4589 // We already limited them to 200 sats (they are used twice for 100 sats).
4590 // Nothing to do here.
4593 // Now, attempt to route 180 sats.
4594 // Our algorithm should provide us with these 2 paths.
4595 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4596 assert_eq!(route.paths.len(), 2);
4598 let mut total_value_transferred_msat = 0;
4599 let mut total_paid_msat = 0;
4600 for path in &route.paths {
4601 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4602 total_value_transferred_msat += path.final_value_msat();
4603 for hop in &path.hops {
4604 total_paid_msat += hop.fee_msat;
4607 // If we paid fee, this would be higher.
4608 assert_eq!(total_value_transferred_msat, 180_000);
4609 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4610 assert_eq!(total_fees_paid, 0);
4615 fn fees_on_mpp_route_test() {
4616 // This test makes sure that MPP algorithm properly takes into account
4617 // fees charged on the channels, by making the fees impactful:
4618 // if the fee is not properly accounted for, the behavior is different.
4619 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4620 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4621 let scorer = ln_test_utils::TestScorer::new();
4622 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4623 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4624 let config = UserConfig::default();
4625 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4627 // We need a route consisting of 2 paths:
4628 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4629 // We will route 200 sats, Each path will have 100 sats capacity.
4631 // This test is not particularly stable: e.g.,
4632 // there's a way to route via {node0, node2, node4}.
4633 // It works while pathfinding is deterministic, but can be broken otherwise.
4634 // It's fine to ignore this concern for now.
4636 // Disable other potential paths.
4637 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4638 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4639 short_channel_id: 2,
4642 cltv_expiry_delta: 0,
4643 htlc_minimum_msat: 0,
4644 htlc_maximum_msat: 100_000,
4646 fee_proportional_millionths: 0,
4647 excess_data: Vec::new()
4650 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4651 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4652 short_channel_id: 7,
4655 cltv_expiry_delta: 0,
4656 htlc_minimum_msat: 0,
4657 htlc_maximum_msat: 100_000,
4659 fee_proportional_millionths: 0,
4660 excess_data: Vec::new()
4663 // Path via {node0, node2} is channels {1, 3, 5}.
4664 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4665 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4666 short_channel_id: 1,
4669 cltv_expiry_delta: 0,
4670 htlc_minimum_msat: 0,
4671 htlc_maximum_msat: 100_000,
4673 fee_proportional_millionths: 0,
4674 excess_data: Vec::new()
4676 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4677 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4678 short_channel_id: 3,
4681 cltv_expiry_delta: 0,
4682 htlc_minimum_msat: 0,
4683 htlc_maximum_msat: 100_000,
4685 fee_proportional_millionths: 0,
4686 excess_data: Vec::new()
4689 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4690 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4691 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4692 short_channel_id: 5,
4695 cltv_expiry_delta: 0,
4696 htlc_minimum_msat: 0,
4697 htlc_maximum_msat: 100_000,
4699 fee_proportional_millionths: 0,
4700 excess_data: Vec::new()
4703 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4704 // All channels should be 100 sats capacity. But for the fee experiment,
4705 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4706 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4707 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4708 // so no matter how large are other channels,
4709 // the whole path will be limited by 100 sats with just these 2 conditions:
4710 // - channel 12 capacity is 250 sats
4711 // - fee for channel 6 is 150 sats
4712 // Let's test this by enforcing these 2 conditions and removing other limits.
4713 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4714 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4715 short_channel_id: 12,
4718 cltv_expiry_delta: 0,
4719 htlc_minimum_msat: 0,
4720 htlc_maximum_msat: 250_000,
4722 fee_proportional_millionths: 0,
4723 excess_data: Vec::new()
4725 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4726 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4727 short_channel_id: 13,
4730 cltv_expiry_delta: 0,
4731 htlc_minimum_msat: 0,
4732 htlc_maximum_msat: MAX_VALUE_MSAT,
4734 fee_proportional_millionths: 0,
4735 excess_data: Vec::new()
4738 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4739 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4740 short_channel_id: 6,
4743 cltv_expiry_delta: 0,
4744 htlc_minimum_msat: 0,
4745 htlc_maximum_msat: MAX_VALUE_MSAT,
4746 fee_base_msat: 150_000,
4747 fee_proportional_millionths: 0,
4748 excess_data: Vec::new()
4750 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4751 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4752 short_channel_id: 11,
4755 cltv_expiry_delta: 0,
4756 htlc_minimum_msat: 0,
4757 htlc_maximum_msat: MAX_VALUE_MSAT,
4759 fee_proportional_millionths: 0,
4760 excess_data: Vec::new()
4764 // Attempt to route more than available results in a failure.
4765 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4766 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4767 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4768 } else { panic!(); }
4772 // Now, attempt to route 200 sats (exact amount we can route).
4773 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4774 assert_eq!(route.paths.len(), 2);
4776 let mut total_amount_paid_msat = 0;
4777 for path in &route.paths {
4778 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4779 total_amount_paid_msat += path.final_value_msat();
4781 assert_eq!(total_amount_paid_msat, 200_000);
4782 assert_eq!(route.get_total_fees(), 150_000);
4787 fn mpp_with_last_hops() {
4788 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4789 // via a single last-hop route hint, we'd fail to route if we first collected routes
4790 // totaling close but not quite enough to fund the full payment.
4792 // This was because we considered last-hop hints to have exactly the sought payment amount
4793 // instead of the amount we were trying to collect, needlessly limiting our path searching
4794 // at the very first hop.
4796 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4797 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4798 // to only have the remaining to-collect amount in available liquidity.
4800 // This bug appeared in production in some specific channel configurations.
4801 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4802 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4803 let scorer = ln_test_utils::TestScorer::new();
4804 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4805 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4806 let config = UserConfig::default();
4807 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
4808 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4809 src_node_id: nodes[2],
4810 short_channel_id: 42,
4811 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4812 cltv_expiry_delta: 42,
4813 htlc_minimum_msat: None,
4814 htlc_maximum_msat: None,
4815 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
4817 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4818 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4819 // would first use the no-fee route and then fail to find a path along the second route as
4820 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4821 // under 5% of our payment amount.
4822 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4824 short_channel_id: 1,
4827 cltv_expiry_delta: (5 << 4) | 5,
4828 htlc_minimum_msat: 0,
4829 htlc_maximum_msat: 99_000,
4830 fee_base_msat: u32::max_value(),
4831 fee_proportional_millionths: u32::max_value(),
4832 excess_data: Vec::new()
4834 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4836 short_channel_id: 2,
4839 cltv_expiry_delta: (5 << 4) | 3,
4840 htlc_minimum_msat: 0,
4841 htlc_maximum_msat: 99_000,
4842 fee_base_msat: u32::max_value(),
4843 fee_proportional_millionths: u32::max_value(),
4844 excess_data: Vec::new()
4846 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4848 short_channel_id: 4,
4851 cltv_expiry_delta: (4 << 4) | 1,
4852 htlc_minimum_msat: 0,
4853 htlc_maximum_msat: MAX_VALUE_MSAT,
4855 fee_proportional_millionths: 0,
4856 excess_data: Vec::new()
4858 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4860 short_channel_id: 13,
4862 flags: 0|2, // Channel disabled
4863 cltv_expiry_delta: (13 << 4) | 1,
4864 htlc_minimum_msat: 0,
4865 htlc_maximum_msat: MAX_VALUE_MSAT,
4867 fee_proportional_millionths: 2000000,
4868 excess_data: Vec::new()
4871 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4873 let mut route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4874 assert_eq!(route.paths.len(), 2);
4875 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
4876 // Paths are manually ordered ordered by SCID, so:
4877 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4878 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4879 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
4880 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4881 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
4882 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
4883 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
4884 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
4885 assert_eq!(route.get_total_fees(), 1);
4886 assert_eq!(route.get_total_amount(), 100_000);
4890 fn drop_lowest_channel_mpp_route_test() {
4891 // This test checks that low-capacity channel is dropped when after
4892 // path finding we realize that we found more capacity than we need.
4893 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4894 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4895 let scorer = ln_test_utils::TestScorer::new();
4896 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4897 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4898 let config = UserConfig::default();
4899 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
4900 .with_max_channel_saturation_power_of_half(0);
4902 // We need a route consisting of 3 paths:
4903 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4905 // The first and the second paths should be sufficient, but the third should be
4906 // cheaper, so that we select it but drop later.
4908 // First, we set limits on these (previously unlimited) channels.
4909 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4911 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4912 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4913 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4914 short_channel_id: 1,
4917 cltv_expiry_delta: 0,
4918 htlc_minimum_msat: 0,
4919 htlc_maximum_msat: 100_000,
4921 fee_proportional_millionths: 0,
4922 excess_data: Vec::new()
4924 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4925 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4926 short_channel_id: 3,
4929 cltv_expiry_delta: 0,
4930 htlc_minimum_msat: 0,
4931 htlc_maximum_msat: 50_000,
4933 fee_proportional_millionths: 0,
4934 excess_data: Vec::new()
4937 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4938 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4939 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4940 short_channel_id: 12,
4943 cltv_expiry_delta: 0,
4944 htlc_minimum_msat: 0,
4945 htlc_maximum_msat: 60_000,
4947 fee_proportional_millionths: 0,
4948 excess_data: Vec::new()
4950 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4951 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4952 short_channel_id: 13,
4955 cltv_expiry_delta: 0,
4956 htlc_minimum_msat: 0,
4957 htlc_maximum_msat: 60_000,
4959 fee_proportional_millionths: 0,
4960 excess_data: Vec::new()
4963 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4964 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4965 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4966 short_channel_id: 2,
4969 cltv_expiry_delta: 0,
4970 htlc_minimum_msat: 0,
4971 htlc_maximum_msat: 20_000,
4973 fee_proportional_millionths: 0,
4974 excess_data: Vec::new()
4976 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4977 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4978 short_channel_id: 4,
4981 cltv_expiry_delta: 0,
4982 htlc_minimum_msat: 0,
4983 htlc_maximum_msat: 20_000,
4985 fee_proportional_millionths: 0,
4986 excess_data: Vec::new()
4990 // Attempt to route more than available results in a failure.
4991 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4992 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4993 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4994 } else { panic!(); }
4998 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4999 // Our algorithm should provide us with these 3 paths.
5000 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5001 assert_eq!(route.paths.len(), 3);
5002 let mut total_amount_paid_msat = 0;
5003 for path in &route.paths {
5004 assert_eq!(path.hops.len(), 2);
5005 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5006 total_amount_paid_msat += path.final_value_msat();
5008 assert_eq!(total_amount_paid_msat, 125_000);
5012 // Attempt to route without the last small cheap channel
5013 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5014 assert_eq!(route.paths.len(), 2);
5015 let mut total_amount_paid_msat = 0;
5016 for path in &route.paths {
5017 assert_eq!(path.hops.len(), 2);
5018 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5019 total_amount_paid_msat += path.final_value_msat();
5021 assert_eq!(total_amount_paid_msat, 90_000);
5026 fn min_criteria_consistency() {
5027 // Test that we don't use an inconsistent metric between updating and walking nodes during
5028 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5029 // was updated with a different criterion from the heap sorting, resulting in loops in
5030 // calculated paths. We test for that specific case here.
5032 // We construct a network that looks like this:
5034 // node2 -1(3)2- node3
5038 // node1 -1(5)2- node4 -1(1)2- node6
5044 // We create a loop on the side of our real path - our destination is node 6, with a
5045 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5046 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5047 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5048 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5049 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5050 // "previous hop" being set to node 3, creating a loop in the path.
5051 let secp_ctx = Secp256k1::new();
5052 let logger = Arc::new(ln_test_utils::TestLogger::new());
5053 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5054 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5055 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5056 let scorer = ln_test_utils::TestScorer::new();
5057 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5058 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5059 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5061 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5062 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5063 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5064 short_channel_id: 6,
5067 cltv_expiry_delta: (6 << 4) | 0,
5068 htlc_minimum_msat: 0,
5069 htlc_maximum_msat: MAX_VALUE_MSAT,
5071 fee_proportional_millionths: 0,
5072 excess_data: Vec::new()
5074 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5076 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5077 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5078 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5079 short_channel_id: 5,
5082 cltv_expiry_delta: (5 << 4) | 0,
5083 htlc_minimum_msat: 0,
5084 htlc_maximum_msat: MAX_VALUE_MSAT,
5086 fee_proportional_millionths: 0,
5087 excess_data: Vec::new()
5089 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5091 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5092 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5093 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5094 short_channel_id: 4,
5097 cltv_expiry_delta: (4 << 4) | 0,
5098 htlc_minimum_msat: 0,
5099 htlc_maximum_msat: MAX_VALUE_MSAT,
5101 fee_proportional_millionths: 0,
5102 excess_data: Vec::new()
5104 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5106 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5107 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5108 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5109 short_channel_id: 3,
5112 cltv_expiry_delta: (3 << 4) | 0,
5113 htlc_minimum_msat: 0,
5114 htlc_maximum_msat: MAX_VALUE_MSAT,
5116 fee_proportional_millionths: 0,
5117 excess_data: Vec::new()
5119 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5121 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5122 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5123 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5124 short_channel_id: 2,
5127 cltv_expiry_delta: (2 << 4) | 0,
5128 htlc_minimum_msat: 0,
5129 htlc_maximum_msat: MAX_VALUE_MSAT,
5131 fee_proportional_millionths: 0,
5132 excess_data: Vec::new()
5135 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5136 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5137 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5138 short_channel_id: 1,
5141 cltv_expiry_delta: (1 << 4) | 0,
5142 htlc_minimum_msat: 100,
5143 htlc_maximum_msat: MAX_VALUE_MSAT,
5145 fee_proportional_millionths: 0,
5146 excess_data: Vec::new()
5148 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5151 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5152 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5153 assert_eq!(route.paths.len(), 1);
5154 assert_eq!(route.paths[0].hops.len(), 3);
5156 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5157 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5158 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5159 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5160 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5161 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5163 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5164 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5165 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5166 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5167 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5168 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5170 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5171 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5172 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5173 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5174 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5175 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5181 fn exact_fee_liquidity_limit() {
5182 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5183 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5184 // we calculated fees on a higher value, resulting in us ignoring such paths.
5185 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5186 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5187 let scorer = ln_test_utils::TestScorer::new();
5188 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5189 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5190 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5192 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5194 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5195 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5196 short_channel_id: 2,
5199 cltv_expiry_delta: 0,
5200 htlc_minimum_msat: 0,
5201 htlc_maximum_msat: 85_000,
5203 fee_proportional_millionths: 0,
5204 excess_data: Vec::new()
5207 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5208 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5209 short_channel_id: 12,
5212 cltv_expiry_delta: (4 << 4) | 1,
5213 htlc_minimum_msat: 0,
5214 htlc_maximum_msat: 270_000,
5216 fee_proportional_millionths: 1000000,
5217 excess_data: Vec::new()
5221 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5222 // 200% fee charged channel 13 in the 1-to-2 direction.
5223 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5224 assert_eq!(route.paths.len(), 1);
5225 assert_eq!(route.paths[0].hops.len(), 2);
5227 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5228 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5229 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5230 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5231 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5232 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5234 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5235 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5236 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5237 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5238 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5239 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5244 fn htlc_max_reduction_below_min() {
5245 // Test that if, while walking the graph, we reduce the value being sent to meet an
5246 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5247 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5248 // resulting in us thinking there is no possible path, even if other paths exist.
5249 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5250 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5251 let scorer = ln_test_utils::TestScorer::new();
5252 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5253 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5254 let config = UserConfig::default();
5255 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5257 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5258 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5259 // then try to send 90_000.
5260 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5261 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5262 short_channel_id: 2,
5265 cltv_expiry_delta: 0,
5266 htlc_minimum_msat: 0,
5267 htlc_maximum_msat: 80_000,
5269 fee_proportional_millionths: 0,
5270 excess_data: Vec::new()
5272 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5273 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5274 short_channel_id: 4,
5277 cltv_expiry_delta: (4 << 4) | 1,
5278 htlc_minimum_msat: 90_000,
5279 htlc_maximum_msat: MAX_VALUE_MSAT,
5281 fee_proportional_millionths: 0,
5282 excess_data: Vec::new()
5286 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5287 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5288 // expensive) channels 12-13 path.
5289 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5290 assert_eq!(route.paths.len(), 1);
5291 assert_eq!(route.paths[0].hops.len(), 2);
5293 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5294 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5295 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5296 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5297 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5298 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5300 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5301 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5302 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5303 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5304 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5305 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5310 fn multiple_direct_first_hops() {
5311 // Previously we'd only ever considered one first hop path per counterparty.
5312 // However, as we don't restrict users to one channel per peer, we really need to support
5313 // looking at all first hop paths.
5314 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5315 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5316 // route over multiple channels with the same first hop.
5317 let secp_ctx = Secp256k1::new();
5318 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5319 let logger = Arc::new(ln_test_utils::TestLogger::new());
5320 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5321 let scorer = ln_test_utils::TestScorer::new();
5322 let config = UserConfig::default();
5323 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5324 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5325 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5328 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5329 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5330 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5331 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5332 assert_eq!(route.paths.len(), 1);
5333 assert_eq!(route.paths[0].hops.len(), 1);
5335 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5336 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5337 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5340 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5341 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5342 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5343 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5344 assert_eq!(route.paths.len(), 2);
5345 assert_eq!(route.paths[0].hops.len(), 1);
5346 assert_eq!(route.paths[1].hops.len(), 1);
5348 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5349 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5351 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5352 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5354 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5355 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5359 // If we have a bunch of outbound channels to the same node, where most are not
5360 // sufficient to pay the full payment, but one is, we should default to just using the
5361 // one single channel that has sufficient balance, avoiding MPP.
5363 // If we have several options above the 3xpayment value threshold, we should pick the
5364 // smallest of them, avoiding further fragmenting our available outbound balance to
5366 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5367 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5368 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5369 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5370 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5371 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5372 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5373 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5374 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5375 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5376 assert_eq!(route.paths.len(), 1);
5377 assert_eq!(route.paths[0].hops.len(), 1);
5379 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5380 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5381 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5386 fn prefers_shorter_route_with_higher_fees() {
5387 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5388 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5389 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5391 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5392 let scorer = ln_test_utils::TestScorer::new();
5393 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5394 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5395 let route = get_route(
5396 &our_id, &payment_params, &network_graph.read_only(), None, 100,
5397 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5399 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5401 assert_eq!(route.get_total_fees(), 100);
5402 assert_eq!(route.get_total_amount(), 100);
5403 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5405 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5406 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5407 let scorer = FixedPenaltyScorer::with_penalty(100);
5408 let route = get_route(
5409 &our_id, &payment_params, &network_graph.read_only(), None, 100,
5410 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5412 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5414 assert_eq!(route.get_total_fees(), 300);
5415 assert_eq!(route.get_total_amount(), 100);
5416 assert_eq!(path, vec![2, 4, 7, 10]);
5419 struct BadChannelScorer {
5420 short_channel_id: u64,
5424 impl Writeable for BadChannelScorer {
5425 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5427 impl Score for BadChannelScorer {
5428 type ScoreParams = ();
5429 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5430 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5433 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5434 fn payment_path_successful(&mut self, _path: &Path) {}
5435 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5436 fn probe_successful(&mut self, _path: &Path) {}
5439 struct BadNodeScorer {
5444 impl Writeable for BadNodeScorer {
5445 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5448 impl Score for BadNodeScorer {
5449 type ScoreParams = ();
5450 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5451 if *target == self.node_id { u64::max_value() } else { 0 }
5454 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5455 fn payment_path_successful(&mut self, _path: &Path) {}
5456 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5457 fn probe_successful(&mut self, _path: &Path) {}
5461 fn avoids_routing_through_bad_channels_and_nodes() {
5462 let (secp_ctx, network, _, _, logger) = build_graph();
5463 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5464 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5465 let network_graph = network.read_only();
5467 // A path to nodes[6] exists when no penalties are applied to any channel.
5468 let scorer = ln_test_utils::TestScorer::new();
5469 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5470 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5471 let route = get_route(
5472 &our_id, &payment_params, &network_graph, None, 100,
5473 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5475 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5477 assert_eq!(route.get_total_fees(), 100);
5478 assert_eq!(route.get_total_amount(), 100);
5479 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5481 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5482 let scorer = BadChannelScorer { short_channel_id: 6 };
5483 let route = get_route(
5484 &our_id, &payment_params, &network_graph, None, 100,
5485 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5487 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5489 assert_eq!(route.get_total_fees(), 300);
5490 assert_eq!(route.get_total_amount(), 100);
5491 assert_eq!(path, vec![2, 4, 7, 10]);
5493 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5494 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5496 &our_id, &payment_params, &network_graph, None, 100,
5497 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5499 Err(LightningError { err, .. } ) => {
5500 assert_eq!(err, "Failed to find a path to the given destination");
5502 Ok(_) => panic!("Expected error"),
5507 fn total_fees_single_path() {
5509 paths: vec![Path { hops: vec![
5511 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5512 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5513 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5516 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5517 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5518 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5521 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5522 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5523 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5525 ], blinded_tail: None }],
5526 payment_params: None,
5529 assert_eq!(route.get_total_fees(), 250);
5530 assert_eq!(route.get_total_amount(), 225);
5534 fn total_fees_multi_path() {
5536 paths: vec![Path { hops: vec![
5538 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5539 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5540 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5543 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5544 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5545 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5547 ], blinded_tail: None }, Path { hops: vec![
5549 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5550 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5551 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5554 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5555 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5556 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5558 ], blinded_tail: None }],
5559 payment_params: None,
5562 assert_eq!(route.get_total_fees(), 200);
5563 assert_eq!(route.get_total_amount(), 300);
5567 fn total_empty_route_no_panic() {
5568 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5569 // would both panic if the route was completely empty. We test to ensure they return 0
5570 // here, even though its somewhat nonsensical as a route.
5571 let route = Route { paths: Vec::new(), payment_params: None };
5573 assert_eq!(route.get_total_fees(), 0);
5574 assert_eq!(route.get_total_amount(), 0);
5578 fn limits_total_cltv_delta() {
5579 let (secp_ctx, network, _, _, logger) = build_graph();
5580 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5581 let network_graph = network.read_only();
5583 let scorer = ln_test_utils::TestScorer::new();
5585 // Make sure that generally there is at least one route available
5586 let feasible_max_total_cltv_delta = 1008;
5587 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5588 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5589 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5590 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5591 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5592 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5593 assert_ne!(path.len(), 0);
5595 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5596 let fail_max_total_cltv_delta = 23;
5597 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5598 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5599 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
5601 Err(LightningError { err, .. } ) => {
5602 assert_eq!(err, "Failed to find a path to the given destination");
5604 Ok(_) => panic!("Expected error"),
5609 fn avoids_recently_failed_paths() {
5610 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5611 // randomly inserting channels into it until we can't find a route anymore.
5612 let (secp_ctx, network, _, _, logger) = build_graph();
5613 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5614 let network_graph = network.read_only();
5616 let scorer = ln_test_utils::TestScorer::new();
5617 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5618 .with_max_path_count(1);
5619 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5620 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5622 // We should be able to find a route initially, and then after we fail a few random
5623 // channels eventually we won't be able to any longer.
5624 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).is_ok());
5626 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
5627 for chan in route.paths[0].hops.iter() {
5628 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5630 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5631 % route.paths[0].hops.len();
5632 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
5638 fn limits_path_length() {
5639 let (secp_ctx, network, _, _, logger) = build_line_graph();
5640 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5641 let network_graph = network.read_only();
5643 let scorer = ln_test_utils::TestScorer::new();
5644 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5645 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5647 // First check we can actually create a long route on this graph.
5648 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
5649 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100,
5650 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5651 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5652 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5654 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5655 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
5656 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100,
5657 Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
5659 Err(LightningError { err, .. } ) => {
5660 assert_eq!(err, "Failed to find a path to the given destination");
5662 Ok(_) => panic!("Expected error"),
5667 fn adds_and_limits_cltv_offset() {
5668 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5669 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5671 let scorer = ln_test_utils::TestScorer::new();
5673 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5674 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5675 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5676 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5677 assert_eq!(route.paths.len(), 1);
5679 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5681 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5682 let mut route_default = route.clone();
5683 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5684 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5685 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5686 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5687 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5689 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5690 let mut route_limited = route.clone();
5691 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5692 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5693 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5694 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5695 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5699 fn adds_plausible_cltv_offset() {
5700 let (secp_ctx, network, _, _, logger) = build_graph();
5701 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5702 let network_graph = network.read_only();
5703 let network_nodes = network_graph.nodes();
5704 let network_channels = network_graph.channels();
5705 let scorer = ln_test_utils::TestScorer::new();
5706 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
5707 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5708 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5710 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100,
5711 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5712 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5714 let mut path_plausibility = vec![];
5716 for p in route.paths {
5717 // 1. Select random observation point
5718 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5719 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5721 prng.process_in_place(&mut random_bytes);
5722 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
5723 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
5725 // 2. Calculate what CLTV expiry delta we would observe there
5726 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5728 // 3. Starting from the observation point, find candidate paths
5729 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5730 candidates.push_back((observation_point, vec![]));
5732 let mut found_plausible_candidate = false;
5734 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5735 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5736 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5737 found_plausible_candidate = true;
5738 break 'candidate_loop;
5742 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5743 for channel_id in &cur_node.channels {
5744 if let Some(channel_info) = network_channels.get(&channel_id) {
5745 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5746 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
5747 if cur_path_cltv_deltas.iter().sum::<u32>()
5748 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5749 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5750 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5751 candidates.push_back((*next_id, new_path_cltv_deltas));
5759 path_plausibility.push(found_plausible_candidate);
5761 assert!(path_plausibility.iter().all(|x| *x));
5765 fn builds_correct_path_from_hops() {
5766 let (secp_ctx, network, _, _, logger) = build_graph();
5767 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5768 let network_graph = network.read_only();
5770 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5771 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5773 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
5774 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5775 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5776 &network_graph, 100, Arc::clone(&logger), &random_seed_bytes).unwrap();
5777 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5778 assert_eq!(hops.len(), route.paths[0].hops.len());
5779 for (idx, hop_pubkey) in hops.iter().enumerate() {
5780 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5785 fn avoids_saturating_channels() {
5786 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5787 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5788 let decay_params = ProbabilisticScoringDecayParameters::default();
5789 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
5791 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5792 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5793 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5794 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5795 short_channel_id: 4,
5798 cltv_expiry_delta: (4 << 4) | 1,
5799 htlc_minimum_msat: 0,
5800 htlc_maximum_msat: 250_000_000,
5802 fee_proportional_millionths: 0,
5803 excess_data: Vec::new()
5805 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5806 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5807 short_channel_id: 13,
5810 cltv_expiry_delta: (13 << 4) | 1,
5811 htlc_minimum_msat: 0,
5812 htlc_maximum_msat: 250_000_000,
5814 fee_proportional_millionths: 0,
5815 excess_data: Vec::new()
5818 let config = UserConfig::default();
5819 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5820 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5821 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5822 // 100,000 sats is less than the available liquidity on each channel, set above.
5823 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000_000, Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
5824 assert_eq!(route.paths.len(), 2);
5825 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
5826 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
5829 #[cfg(not(feature = "no-std"))]
5830 pub(super) fn random_init_seed() -> u64 {
5831 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5832 use core::hash::{BuildHasher, Hasher};
5833 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5834 println!("Using seed of {}", seed);
5839 #[cfg(not(feature = "no-std"))]
5840 fn generate_routes() {
5841 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
5843 let logger = ln_test_utils::TestLogger::new();
5844 let graph = match super::bench_utils::read_network_graph(&logger) {
5852 let params = ProbabilisticScoringFeeParameters::default();
5853 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
5854 let features = super::InvoiceFeatures::empty();
5856 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
5860 #[cfg(not(feature = "no-std"))]
5861 fn generate_routes_mpp() {
5862 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
5864 let logger = ln_test_utils::TestLogger::new();
5865 let graph = match super::bench_utils::read_network_graph(&logger) {
5873 let params = ProbabilisticScoringFeeParameters::default();
5874 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
5875 let features = channelmanager::provided_invoice_features(&UserConfig::default());
5877 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
5881 #[cfg(not(feature = "no-std"))]
5882 fn generate_large_mpp_routes() {
5883 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
5885 let logger = ln_test_utils::TestLogger::new();
5886 let graph = match super::bench_utils::read_network_graph(&logger) {
5894 let params = ProbabilisticScoringFeeParameters::default();
5895 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
5896 let features = channelmanager::provided_invoice_features(&UserConfig::default());
5898 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
5902 fn honors_manual_penalties() {
5903 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5904 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5906 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5907 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5909 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
5910 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
5912 // First check set manual penalties are returned by the scorer.
5913 let usage = ChannelUsage {
5915 inflight_htlc_msat: 0,
5916 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
5918 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5919 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5920 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
5922 // Then check we can get a normal route
5923 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
5924 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
5925 assert!(route.is_ok());
5927 // Then check that we can't get a route if we ban an intermediate node.
5928 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
5929 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
5930 assert!(route.is_err());
5932 // Finally make sure we can route again, when we remove the ban.
5933 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5934 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
5935 assert!(route.is_ok());
5939 fn abide_by_route_hint_max_htlc() {
5940 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
5941 // params in the final route.
5942 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5943 let netgraph = network_graph.read_only();
5944 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5945 let scorer = ln_test_utils::TestScorer::new();
5946 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5947 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5948 let config = UserConfig::default();
5950 let max_htlc_msat = 50_000;
5951 let route_hint_1 = RouteHint(vec![RouteHintHop {
5952 src_node_id: nodes[2],
5953 short_channel_id: 42,
5956 proportional_millionths: 0,
5958 cltv_expiry_delta: 10,
5959 htlc_minimum_msat: None,
5960 htlc_maximum_msat: Some(max_htlc_msat),
5962 let dest_node_id = ln_test_utils::pubkey(42);
5963 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
5964 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
5965 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5967 // Make sure we'll error if our route hints don't have enough liquidity according to their
5968 // htlc_maximum_msat.
5969 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
5970 &payment_params, &netgraph, None, max_htlc_msat + 1, Arc::clone(&logger), &scorer, &(),
5973 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5974 } else { panic!(); }
5976 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
5977 let mut route_hint_2 = route_hint_1.clone();
5978 route_hint_2.0[0].short_channel_id = 43;
5979 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
5980 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
5981 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5982 let route = get_route(&our_id, &payment_params, &netgraph, None, max_htlc_msat + 1,
5983 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5984 assert_eq!(route.paths.len(), 2);
5985 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
5986 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
5990 fn direct_channel_to_hints_with_max_htlc() {
5991 // Check that if we have a first hop channel peer that's connected to multiple provided route
5992 // hints, that we properly split the payment between the route hints if needed.
5993 let logger = Arc::new(ln_test_utils::TestLogger::new());
5994 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5995 let scorer = ln_test_utils::TestScorer::new();
5996 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5997 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5998 let config = UserConfig::default();
6000 let our_node_id = ln_test_utils::pubkey(42);
6001 let intermed_node_id = ln_test_utils::pubkey(43);
6002 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6004 let amt_msat = 900_000;
6005 let max_htlc_msat = 500_000;
6006 let route_hint_1 = RouteHint(vec![RouteHintHop {
6007 src_node_id: intermed_node_id,
6008 short_channel_id: 44,
6011 proportional_millionths: 0,
6013 cltv_expiry_delta: 10,
6014 htlc_minimum_msat: None,
6015 htlc_maximum_msat: Some(max_htlc_msat),
6017 src_node_id: intermed_node_id,
6018 short_channel_id: 45,
6021 proportional_millionths: 0,
6023 cltv_expiry_delta: 10,
6024 htlc_minimum_msat: None,
6025 // Check that later route hint max htlcs don't override earlier ones
6026 htlc_maximum_msat: Some(max_htlc_msat - 50),
6028 let mut route_hint_2 = route_hint_1.clone();
6029 route_hint_2.0[0].short_channel_id = 46;
6030 route_hint_2.0[1].short_channel_id = 47;
6031 let dest_node_id = ln_test_utils::pubkey(44);
6032 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6033 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6034 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6036 let route = get_route(&our_node_id, &payment_params, &network_graph.read_only(),
6037 Some(&first_hop.iter().collect::<Vec<_>>()), amt_msat, Arc::clone(&logger), &scorer, &(),
6038 &random_seed_bytes).unwrap();
6039 assert_eq!(route.paths.len(), 2);
6040 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6041 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6042 assert_eq!(route.get_total_amount(), amt_msat);
6044 // Re-run but with two first hop channels connected to the same route hint peers that must be
6046 let first_hops = vec![
6047 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6048 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6050 let route = get_route(&our_node_id, &payment_params, &network_graph.read_only(),
6051 Some(&first_hops.iter().collect::<Vec<_>>()), amt_msat, Arc::clone(&logger), &scorer, &(),
6052 &random_seed_bytes).unwrap();
6053 assert_eq!(route.paths.len(), 2);
6054 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6055 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6056 assert_eq!(route.get_total_amount(), amt_msat);
6060 fn blinded_route_ser() {
6061 let blinded_path_1 = BlindedPath {
6062 introduction_node_id: ln_test_utils::pubkey(42),
6063 blinding_point: ln_test_utils::pubkey(43),
6065 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6066 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6069 let blinded_path_2 = BlindedPath {
6070 introduction_node_id: ln_test_utils::pubkey(46),
6071 blinding_point: ln_test_utils::pubkey(47),
6073 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6074 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6077 // (De)serialize a Route with 1 blinded path out of two total paths.
6078 let mut route = Route { paths: vec![Path {
6079 hops: vec![RouteHop {
6080 pubkey: ln_test_utils::pubkey(50),
6081 node_features: NodeFeatures::empty(),
6082 short_channel_id: 42,
6083 channel_features: ChannelFeatures::empty(),
6085 cltv_expiry_delta: 0,
6087 blinded_tail: Some(BlindedTail {
6088 hops: blinded_path_1.blinded_hops,
6089 blinding_point: blinded_path_1.blinding_point,
6090 excess_final_cltv_expiry_delta: 40,
6091 final_value_msat: 100,
6093 hops: vec![RouteHop {
6094 pubkey: ln_test_utils::pubkey(51),
6095 node_features: NodeFeatures::empty(),
6096 short_channel_id: 43,
6097 channel_features: ChannelFeatures::empty(),
6099 cltv_expiry_delta: 0,
6100 }], blinded_tail: None }],
6101 payment_params: None,
6103 let encoded_route = route.encode();
6104 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6105 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6106 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6108 // (De)serialize a Route with two paths, each containing a blinded tail.
6109 route.paths[1].blinded_tail = Some(BlindedTail {
6110 hops: blinded_path_2.blinded_hops,
6111 blinding_point: blinded_path_2.blinding_point,
6112 excess_final_cltv_expiry_delta: 41,
6113 final_value_msat: 101,
6115 let encoded_route = route.encode();
6116 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6117 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6118 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6122 fn blinded_path_inflight_processing() {
6123 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6124 // account for the blinded tail's final amount_msat.
6125 let mut inflight_htlcs = InFlightHtlcs::new();
6126 let blinded_path = BlindedPath {
6127 introduction_node_id: ln_test_utils::pubkey(43),
6128 blinding_point: ln_test_utils::pubkey(48),
6129 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6132 hops: vec![RouteHop {
6133 pubkey: ln_test_utils::pubkey(42),
6134 node_features: NodeFeatures::empty(),
6135 short_channel_id: 42,
6136 channel_features: ChannelFeatures::empty(),
6138 cltv_expiry_delta: 0,
6141 pubkey: blinded_path.introduction_node_id,
6142 node_features: NodeFeatures::empty(),
6143 short_channel_id: 43,
6144 channel_features: ChannelFeatures::empty(),
6146 cltv_expiry_delta: 0,
6148 blinded_tail: Some(BlindedTail {
6149 hops: blinded_path.blinded_hops,
6150 blinding_point: blinded_path.blinding_point,
6151 excess_final_cltv_expiry_delta: 0,
6152 final_value_msat: 200,
6155 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6156 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6157 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6161 fn blinded_path_cltv_shadow_offset() {
6162 // Make sure we add a shadow offset when sending to blinded paths.
6163 let blinded_path = BlindedPath {
6164 introduction_node_id: ln_test_utils::pubkey(43),
6165 blinding_point: ln_test_utils::pubkey(44),
6167 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6168 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6171 let mut route = Route { paths: vec![Path {
6172 hops: vec![RouteHop {
6173 pubkey: ln_test_utils::pubkey(42),
6174 node_features: NodeFeatures::empty(),
6175 short_channel_id: 42,
6176 channel_features: ChannelFeatures::empty(),
6178 cltv_expiry_delta: 0,
6181 pubkey: blinded_path.introduction_node_id,
6182 node_features: NodeFeatures::empty(),
6183 short_channel_id: 43,
6184 channel_features: ChannelFeatures::empty(),
6186 cltv_expiry_delta: 0,
6189 blinded_tail: Some(BlindedTail {
6190 hops: blinded_path.blinded_hops,
6191 blinding_point: blinded_path.blinding_point,
6192 excess_final_cltv_expiry_delta: 0,
6193 final_value_msat: 200,
6195 }], payment_params: None};
6197 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6198 let (_, network_graph, _, _, _) = build_line_graph();
6199 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6200 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6201 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6205 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
6206 pub(crate) mod bench_utils {
6210 use bitcoin::hashes::Hash;
6211 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
6213 use crate::chain::transaction::OutPoint;
6214 use crate::sign::{EntropySource, KeysManager};
6215 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
6216 use crate::ln::features::InvoiceFeatures;
6217 use crate::routing::gossip::NetworkGraph;
6218 use crate::util::config::UserConfig;
6219 use crate::util::ser::ReadableArgs;
6220 use crate::util::test_utils::TestLogger;
6222 /// Tries to open a network graph file, or panics with a URL to fetch it.
6223 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
6224 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
6225 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
6226 .or_else(|_| { // Fall back to guessing based on the binary location
6227 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
6228 let mut path = std::env::current_exe().unwrap();
6229 path.pop(); // lightning-...
6231 path.pop(); // debug
6232 path.pop(); // target
6233 path.push("lightning");
6234 path.push("net_graph-2023-01-18.bin");
6237 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
6238 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
6239 let mut path = std::env::current_exe().unwrap();
6240 path.pop(); // bench...
6242 path.pop(); // debug
6243 path.pop(); // target
6244 path.pop(); // bench
6245 path.push("lightning");
6246 path.push("net_graph-2023-01-18.bin");
6249 .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");
6250 #[cfg(require_route_graph_test)]
6251 return Ok(res.unwrap());
6252 #[cfg(not(require_route_graph_test))]
6256 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
6257 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
6260 pub(crate) fn payer_pubkey() -> PublicKey {
6261 let secp_ctx = Secp256k1::new();
6262 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
6266 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
6268 channel_id: [0; 32],
6269 counterparty: ChannelCounterparty {
6270 features: channelmanager::provided_init_features(&UserConfig::default()),
6272 unspendable_punishment_reserve: 0,
6273 forwarding_info: None,
6274 outbound_htlc_minimum_msat: None,
6275 outbound_htlc_maximum_msat: None,
6277 funding_txo: Some(OutPoint {
6278 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
6281 short_channel_id: Some(1),
6282 inbound_scid_alias: None,
6283 outbound_scid_alias: None,
6284 channel_value_satoshis: 10_000_000_000,
6286 balance_msat: 10_000_000_000,
6287 outbound_capacity_msat: 10_000_000_000,
6288 next_outbound_htlc_minimum_msat: 0,
6289 next_outbound_htlc_limit_msat: 10_000_000_000,
6290 inbound_capacity_msat: 0,
6291 unspendable_punishment_reserve: None,
6292 confirmations_required: None,
6293 confirmations: None,
6294 force_close_spend_delay: None,
6296 is_channel_ready: true,
6299 inbound_htlc_minimum_msat: None,
6300 inbound_htlc_maximum_msat: None,
6302 feerate_sat_per_1000_weight: None,
6306 pub(crate) fn generate_test_routes<S: Score>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
6307 score_params: &S::ScoreParams, features: InvoiceFeatures, mut seed: u64,
6308 starting_amount: u64, route_count: usize,
6309 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
6310 let payer = payer_pubkey();
6311 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6312 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6314 let nodes = graph.read_only().nodes().clone();
6315 let mut route_endpoints = Vec::new();
6316 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
6317 // with some routes we picked being un-routable.
6318 for _ in 0..route_count * 3 / 2 {
6320 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6321 let src = PublicKey::from_slice(nodes.unordered_keys()
6322 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
6323 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6324 let dst = PublicKey::from_slice(nodes.unordered_keys()
6325 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
6326 let params = PaymentParameters::from_node_id(dst, 42)
6327 .with_bolt11_features(features.clone()).unwrap();
6328 let first_hop = first_hop(src);
6329 let amt = starting_amount + seed % 1_000_000;
6331 get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]),
6332 amt, &TestLogger::new(), &scorer, score_params, &random_seed_bytes).is_ok();
6334 // ...and seed the scorer with success and failure data...
6335 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6336 let mut score_amt = seed % 1_000_000_000;
6338 // Generate fail/success paths for a wider range of potential amounts with
6339 // MPP enabled to give us a chance to apply penalties for more potential
6341 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
6342 let params = PaymentParameters::from_node_id(dst, 42)
6343 .with_bolt11_features(mpp_features).unwrap();
6345 let route_res = get_route(&payer, ¶ms, &graph.read_only(),
6346 Some(&[&first_hop]), score_amt, &TestLogger::new(), &scorer,
6347 score_params, &random_seed_bytes);
6348 if let Ok(route) = route_res {
6349 for path in route.paths {
6350 if seed & 0x80 == 0 {
6351 scorer.payment_path_successful(&path);
6353 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
6354 scorer.payment_path_failed(&path, short_channel_id);
6356 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6360 // If we couldn't find a path with a higer amount, reduce and try again.
6364 route_endpoints.push((first_hop, params, amt));
6370 // Because we've changed channel scores, it's possible we'll take different routes to the
6371 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
6372 // requires a too-high CLTV delta.
6373 route_endpoints.retain(|(first_hop, params, amt)| {
6374 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt,
6375 &TestLogger::new(), &scorer, score_params, &random_seed_bytes).is_ok()
6377 route_endpoints.truncate(route_count);
6378 assert_eq!(route_endpoints.len(), route_count);
6386 use crate::sign::{EntropySource, KeysManager};
6387 use crate::ln::channelmanager;
6388 use crate::ln::features::InvoiceFeatures;
6389 use crate::routing::gossip::NetworkGraph;
6390 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
6391 use crate::util::config::UserConfig;
6392 use crate::util::logger::{Logger, Record};
6393 use crate::util::test_utils::TestLogger;
6395 use criterion::Criterion;
6397 struct DummyLogger {}
6398 impl Logger for DummyLogger {
6399 fn log(&self, _record: &Record) {}
6402 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
6403 let logger = TestLogger::new();
6404 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6405 let scorer = FixedPenaltyScorer::with_penalty(0);
6406 generate_routes(bench, &network_graph, scorer, &(), InvoiceFeatures::empty(), 0,
6407 "generate_routes_with_zero_penalty_scorer");
6410 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
6411 let logger = TestLogger::new();
6412 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6413 let scorer = FixedPenaltyScorer::with_penalty(0);
6414 generate_routes(bench, &network_graph, scorer, &(),
6415 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
6416 "generate_mpp_routes_with_zero_penalty_scorer");
6419 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6420 let logger = TestLogger::new();
6421 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6422 let params = ProbabilisticScoringFeeParameters::default();
6423 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6424 generate_routes(bench, &network_graph, scorer, ¶ms, InvoiceFeatures::empty(), 0,
6425 "generate_routes_with_probabilistic_scorer");
6428 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6429 let logger = TestLogger::new();
6430 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6431 let params = ProbabilisticScoringFeeParameters::default();
6432 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6433 generate_routes(bench, &network_graph, scorer, ¶ms,
6434 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
6435 "generate_mpp_routes_with_probabilistic_scorer");
6438 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6439 let logger = TestLogger::new();
6440 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6441 let params = ProbabilisticScoringFeeParameters::default();
6442 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6443 generate_routes(bench, &network_graph, scorer, ¶ms,
6444 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
6445 "generate_large_mpp_routes_with_probabilistic_scorer");
6448 fn generate_routes<S: Score>(
6449 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
6450 score_params: &S::ScoreParams, features: InvoiceFeatures, starting_amount: u64,
6451 bench_name: &'static str,
6453 let payer = bench_utils::payer_pubkey();
6454 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6455 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6457 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
6458 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
6460 // ...then benchmark finding paths between the nodes we learned.
6462 bench.bench_function(bench_name, |b| b.iter(|| {
6463 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
6464 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt,
6465 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());