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::{Bolt11InvoiceFeatures, Bolt12InvoiceFeatures, ChannelFeatures, NodeFeatures};
20 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
21 use crate::offers::invoice::{BlindedPayInfo, Bolt12Invoice};
22 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
23 use crate::routing::scoring::{ChannelUsage, LockableScore, ScoreLookUp};
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;
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: ScoreLookUp<ScoreParams = SP>> where
38 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
42 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> DefaultRouter<G, L, S, SP, Sc> where
49 S::Target: for <'a> LockableScore<'a, ScoreLookUp = 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: ScoreLookUp<ScoreParams = SP>> Router for DefaultRouter<G, L, S, SP, Sc> where
60 S::Target: for <'a> LockableScore<'a, ScoreLookUp = 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).to_byte_array();
72 *locked_random_seed_bytes
75 payer, params, &self.network_graph, first_hops, &*self.logger,
76 &ScorerAccountingForInFlightHtlcs::new(self.scorer.read_lock(), &inflight_htlcs),
83 /// A trait defining behavior for routing a payment.
85 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
87 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
88 /// and [`RouteParameters::final_value_msat`], respectively.
90 &self, payer: &PublicKey, route_params: &RouteParameters,
91 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
92 ) -> Result<Route, LightningError>;
94 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
96 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
97 /// and [`RouteParameters::final_value_msat`], respectively.
99 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
101 fn find_route_with_id(
102 &self, payer: &PublicKey, route_params: &RouteParameters,
103 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
104 _payment_hash: PaymentHash, _payment_id: PaymentId
105 ) -> Result<Route, LightningError> {
106 self.find_route(payer, route_params, first_hops, inflight_htlcs)
110 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
112 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
115 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
116 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Deref> where S::Target: ScoreLookUp {
118 // Maps a channel's short channel id and its direction to the liquidity used up.
119 inflight_htlcs: &'a InFlightHtlcs,
121 impl<'a, S: Deref> ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
122 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
123 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
124 ScorerAccountingForInFlightHtlcs {
131 impl<'a, S: Deref> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, S> where S::Target: ScoreLookUp {
132 type ScoreParams = <S::Target as ScoreLookUp>::ScoreParams;
133 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
134 let target = match candidate.target() {
135 Some(target) => target,
136 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
138 let short_channel_id = match candidate.short_channel_id() {
139 Some(short_channel_id) => short_channel_id,
140 None => return self.scorer.channel_penalty_msat(candidate, usage, score_params),
142 let source = candidate.source();
143 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
144 &source, &target, short_channel_id
146 let usage = ChannelUsage {
147 inflight_htlc_msat: usage.inflight_htlc_msat.saturating_add(used_liquidity),
151 self.scorer.channel_penalty_msat(candidate, usage, score_params)
153 self.scorer.channel_penalty_msat(candidate, usage, score_params)
158 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
159 /// in-use channel liquidity.
161 pub struct InFlightHtlcs(
162 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
163 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
164 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
166 HashMap<(u64, bool), u64>
170 /// Constructs an empty `InFlightHtlcs`.
171 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
173 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
174 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
175 if path.hops.is_empty() { return };
177 let mut cumulative_msat = 0;
178 if let Some(tail) = &path.blinded_tail {
179 cumulative_msat += tail.final_value_msat;
182 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
183 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
184 // the router excludes the payer node. In the following lines, the payer's information is
185 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
186 // in our sliding window of two.
187 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
188 .map(|hop| hop.pubkey)
189 .chain(core::iter::once(payer_node_id));
191 // Taking the reversed vector from above, we zip it with just the reversed hops list to
192 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
193 // the total amount sent.
194 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
195 cumulative_msat += next_hop.fee_msat;
197 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
198 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
199 .or_insert(cumulative_msat);
203 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
205 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
207 .entry((channel_scid, source < target))
208 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
209 .or_insert(used_msat);
212 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
214 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
215 self.0.get(&(channel_scid, source < target)).map(|v| *v)
219 impl Writeable for InFlightHtlcs {
220 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
223 impl Readable for InFlightHtlcs {
224 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
225 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
226 Ok(Self(infight_map))
230 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
231 /// that leads to it.
232 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
233 pub struct RouteHop {
234 /// The node_id of the node at this hop.
235 pub pubkey: PublicKey,
236 /// The node_announcement features of the node at this hop. For the last hop, these may be
237 /// amended to match the features present in the invoice this node generated.
238 pub node_features: NodeFeatures,
239 /// The channel that should be used from the previous hop to reach this node.
240 pub short_channel_id: u64,
241 /// The channel_announcement features of the channel that should be used from the previous hop
242 /// to reach this node.
243 pub channel_features: ChannelFeatures,
244 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
245 /// If this is the last hop in [`Path::hops`]:
246 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
247 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
249 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
251 /// The CLTV delta added for this hop.
252 /// If this is the last hop in [`Path::hops`]:
253 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
254 /// * otherwise, this is the CLTV delta expected at the destination
256 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
257 pub cltv_expiry_delta: u32,
258 /// Indicates whether this hop is possibly announced in the public network graph.
260 /// Will be `true` if there is a possibility that the channel is publicly known, i.e., if we
261 /// either know for sure it's announced in the public graph, or if any public channels exist
262 /// for which the given `short_channel_id` could be an alias for. Will be `false` if we believe
263 /// the channel to be unannounced.
265 /// Will be `true` for objects serialized with LDK version 0.0.116 and before.
266 pub maybe_announced_channel: bool,
269 impl_writeable_tlv_based!(RouteHop, {
270 (0, pubkey, required),
271 (1, maybe_announced_channel, (default_value, true)),
272 (2, node_features, required),
273 (4, short_channel_id, required),
274 (6, channel_features, required),
275 (8, fee_msat, required),
276 (10, cltv_expiry_delta, required),
279 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
280 /// their [`Bolt12Invoice`].
282 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
283 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
284 pub struct BlindedTail {
285 /// The hops of the [`BlindedPath`] provided by the recipient.
287 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
288 pub hops: Vec<BlindedHop>,
289 /// The blinding point of the [`BlindedPath`] provided by the recipient.
291 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
292 pub blinding_point: PublicKey,
293 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
294 /// inferring the destination. May be 0.
295 pub excess_final_cltv_expiry_delta: u32,
296 /// The total amount paid on this [`Path`], excluding the fees.
297 pub final_value_msat: u64,
300 impl_writeable_tlv_based!(BlindedTail, {
301 (0, hops, required_vec),
302 (2, blinding_point, required),
303 (4, excess_final_cltv_expiry_delta, required),
304 (6, final_value_msat, required),
307 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
308 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
309 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
311 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
312 pub hops: Vec<RouteHop>,
313 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
314 pub blinded_tail: Option<BlindedTail>,
318 /// Gets the fees for a given path, excluding any excess paid to the recipient.
319 pub fn fee_msat(&self) -> u64 {
320 match &self.blinded_tail {
321 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
323 // Do not count last hop of each path since that's the full value of the payment
324 self.hops.split_last().map_or(0,
325 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
330 /// Gets the total amount paid on this [`Path`], excluding the fees.
331 pub fn final_value_msat(&self) -> u64 {
332 match &self.blinded_tail {
333 Some(blinded_tail) => blinded_tail.final_value_msat,
334 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
338 /// Gets the final hop's CLTV expiry delta.
339 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
340 match &self.blinded_tail {
342 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
347 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
348 /// it can take multiple paths. Each path is composed of one or more hops through the network.
349 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
351 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
352 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
354 pub paths: Vec<Path>,
355 /// The `route_params` parameter passed to [`find_route`].
357 /// This is used by `ChannelManager` to track information which may be required for retries.
359 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
360 pub route_params: Option<RouteParameters>,
364 /// Returns the total amount of fees paid on this [`Route`].
366 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
367 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
368 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
370 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
371 pub fn get_total_fees(&self) -> u64 {
372 let overpaid_value_msat = self.route_params.as_ref()
373 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
374 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
377 /// Returns the total amount paid on this [`Route`], excluding the fees.
379 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
380 /// we had to reach the [`htlc_minimum_msat`] limits.
382 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
383 pub fn get_total_amount(&self) -> u64 {
384 self.paths.iter().map(|path| path.final_value_msat()).sum()
388 impl fmt::Display for Route {
389 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
390 log_route!(self).fmt(f)
394 const SERIALIZATION_VERSION: u8 = 1;
395 const MIN_SERIALIZATION_VERSION: u8 = 1;
397 impl Writeable for Route {
398 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
399 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
400 (self.paths.len() as u64).write(writer)?;
401 let mut blinded_tails = Vec::new();
402 for path in self.paths.iter() {
403 (path.hops.len() as u8).write(writer)?;
404 for (idx, hop) in path.hops.iter().enumerate() {
406 if let Some(blinded_tail) = &path.blinded_tail {
407 if blinded_tails.is_empty() {
408 blinded_tails = Vec::with_capacity(path.hops.len());
410 blinded_tails.push(None);
413 blinded_tails.push(Some(blinded_tail));
414 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
417 write_tlv_fields!(writer, {
418 // For compatibility with LDK versions prior to 0.0.117, we take the individual
419 // RouteParameters' fields and reconstruct them on read.
420 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
421 (2, blinded_tails, optional_vec),
422 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
423 (5, self.route_params.as_ref().map(|p| p.max_total_routing_fee_msat), option),
429 impl Readable for Route {
430 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
431 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
432 let path_count: u64 = Readable::read(reader)?;
433 if path_count == 0 { return Err(DecodeError::InvalidValue); }
434 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
435 let mut min_final_cltv_expiry_delta = u32::max_value();
436 for _ in 0..path_count {
437 let hop_count: u8 = Readable::read(reader)?;
438 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
439 for _ in 0..hop_count {
440 hops.push(Readable::read(reader)?);
442 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
443 min_final_cltv_expiry_delta =
444 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
445 paths.push(Path { hops, blinded_tail: None });
447 _init_and_read_len_prefixed_tlv_fields!(reader, {
448 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
449 (2, blinded_tails, optional_vec),
450 (3, final_value_msat, option),
451 (5, max_total_routing_fee_msat, option)
453 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
454 if blinded_tails.len() != 0 {
455 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
456 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
457 path.blinded_tail = blinded_tail_opt;
461 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
462 let route_params = match (payment_params, final_value_msat) {
463 (Some(payment_params), Some(final_value_msat)) => {
464 Some(RouteParameters { payment_params, final_value_msat, max_total_routing_fee_msat })
469 Ok(Route { paths, route_params })
473 /// Parameters needed to find a [`Route`].
475 /// Passed to [`find_route`] and [`build_route_from_hops`].
476 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
477 pub struct RouteParameters {
478 /// The parameters of the failed payment path.
479 pub payment_params: PaymentParameters,
481 /// The amount in msats sent on the failed payment path.
482 pub final_value_msat: u64,
484 /// The maximum total fees, in millisatoshi, that may accrue during route finding.
486 /// This limit also applies to the total fees that may arise while retrying failed payment
489 /// Note that values below a few sats may result in some paths being spuriously ignored.
490 pub max_total_routing_fee_msat: Option<u64>,
493 impl RouteParameters {
494 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
496 /// [`Self::max_total_routing_fee_msat`] defaults to 1% of the payment amount + 50 sats
497 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
498 Self { payment_params, final_value_msat, max_total_routing_fee_msat: Some(final_value_msat / 100 + 50_000) }
502 impl Writeable for RouteParameters {
503 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
504 write_tlv_fields!(writer, {
505 (0, self.payment_params, required),
506 (1, self.max_total_routing_fee_msat, option),
507 (2, self.final_value_msat, required),
508 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
509 // `RouteParameters` directly. For compatibility, we write it here.
510 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
516 impl Readable for RouteParameters {
517 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
518 _init_and_read_len_prefixed_tlv_fields!(reader, {
519 (0, payment_params, (required: ReadableArgs, 0)),
520 (1, max_total_routing_fee_msat, option),
521 (2, final_value_msat, required),
522 (4, final_cltv_delta, option),
524 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
525 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
526 if final_cltv_expiry_delta == &0 {
527 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
532 final_value_msat: final_value_msat.0.unwrap(),
533 max_total_routing_fee_msat,
538 /// Maximum total CTLV difference we allow for a full payment path.
539 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
541 /// Maximum number of paths we allow an (MPP) payment to have.
542 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
543 // limits, but for now more than 10 paths likely carries too much one-path failure.
544 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
546 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
548 // The median hop CLTV expiry delta currently seen in the network.
549 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
551 // During routing, we only consider paths shorter than our maximum length estimate.
552 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
553 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
554 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
556 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
557 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
558 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
559 // (payment_secret and total_msat) = 93 bytes for the final hop.
560 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
561 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
562 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
564 /// Information used to route a payment.
565 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
566 pub struct PaymentParameters {
567 /// Information about the payee, such as their features and route hints for their channels.
570 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
571 pub expiry_time: Option<u64>,
573 /// The maximum total CLTV delta we accept for the route.
574 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
575 pub max_total_cltv_expiry_delta: u32,
577 /// The maximum number of paths that may be used by (MPP) payments.
578 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
579 pub max_path_count: u8,
581 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
582 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
583 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
584 /// increasing failure probability for those paths.
586 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
587 /// restriction have been found. While paths which meet this criteria will be searched for, it
588 /// is ultimately up to the scorer to select them over other paths.
590 /// A value of 0 will allow payments up to and including a channel's total announced usable
591 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
594 pub max_channel_saturation_power_of_half: u8,
596 /// A list of SCIDs which this payment was previously attempted over and which caused the
597 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
599 pub previously_failed_channels: Vec<u64>,
602 impl Writeable for PaymentParameters {
603 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
604 let mut clear_hints = &vec![];
605 let mut blinded_hints = &vec![];
607 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
608 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
610 write_tlv_fields!(writer, {
611 (0, self.payee.node_id(), option),
612 (1, self.max_total_cltv_expiry_delta, required),
613 (2, self.payee.features(), option),
614 (3, self.max_path_count, required),
615 (4, *clear_hints, required_vec),
616 (5, self.max_channel_saturation_power_of_half, required),
617 (6, self.expiry_time, option),
618 (7, self.previously_failed_channels, required_vec),
619 (8, *blinded_hints, optional_vec),
620 (9, self.payee.final_cltv_expiry_delta(), option),
626 impl ReadableArgs<u32> for PaymentParameters {
627 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
628 _init_and_read_len_prefixed_tlv_fields!(reader, {
629 (0, payee_pubkey, option),
630 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
631 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
632 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
633 (4, clear_route_hints, required_vec),
634 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
635 (6, expiry_time, option),
636 (7, previously_failed_channels, optional_vec),
637 (8, blinded_route_hints, optional_vec),
638 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
640 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
641 let payee = if blinded_route_hints.len() != 0 {
642 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
644 route_hints: blinded_route_hints,
645 features: features.and_then(|f: Features| f.bolt12()),
649 route_hints: clear_route_hints,
650 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
651 features: features.and_then(|f| f.bolt11()),
652 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
656 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
657 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
659 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
661 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
667 impl PaymentParameters {
668 /// Creates a payee with the node id of the given `pubkey`.
670 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
672 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
674 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
676 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
677 max_path_count: DEFAULT_MAX_PATH_COUNT,
678 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
679 previously_failed_channels: Vec::new(),
683 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
685 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
688 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
689 /// whether your router will be allowed to find a multi-part route for this payment. If you
690 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
691 /// [`RecipientOnionFields::secret_only`].
693 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
694 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
695 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
696 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
697 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
700 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
701 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
702 /// [`PaymentParameters::expiry_time`].
703 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
704 Self::blinded(invoice.payment_paths().to_vec())
705 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
706 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
709 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
710 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
712 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
714 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
715 max_path_count: DEFAULT_MAX_PATH_COUNT,
716 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
717 previously_failed_channels: Vec::new(),
721 /// Includes the payee's features. Errors if the parameters were not initialized with
722 /// [`PaymentParameters::from_bolt12_invoice`].
724 /// This is not exported to bindings users since bindings don't support move semantics
725 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
727 Payee::Clear { .. } => Err(()),
728 Payee::Blinded { route_hints, .. } =>
729 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
733 /// Includes the payee's features. Errors if the parameters were initialized with
734 /// [`PaymentParameters::from_bolt12_invoice`].
736 /// This is not exported to bindings users since bindings don't support move semantics
737 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
739 Payee::Blinded { .. } => Err(()),
740 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
742 payee: Payee::Clear {
743 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
749 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
750 /// [`PaymentParameters::from_bolt12_invoice`].
752 /// This is not exported to bindings users since bindings don't support move semantics
753 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
755 Payee::Blinded { .. } => Err(()),
756 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
758 payee: Payee::Clear {
759 route_hints, node_id, features, final_cltv_expiry_delta,
765 /// Includes a payment expiration in seconds relative to the UNIX epoch.
767 /// This is not exported to bindings users since bindings don't support move semantics
768 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
769 Self { expiry_time: Some(expiry_time), ..self }
772 /// Includes a limit for the total CLTV expiry delta which is considered during routing
774 /// This is not exported to bindings users since bindings don't support move semantics
775 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
776 Self { max_total_cltv_expiry_delta, ..self }
779 /// Includes a limit for the maximum number of payment paths that may be used.
781 /// This is not exported to bindings users since bindings don't support move semantics
782 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
783 Self { max_path_count, ..self }
786 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
787 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
789 /// This is not exported to bindings users since bindings don't support move semantics
790 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
791 Self { max_channel_saturation_power_of_half, ..self }
795 /// The recipient of a payment, differing based on whether they've hidden their identity with route
797 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
799 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
800 /// will be included in the final [`Route`].
802 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
804 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
805 /// Features supported by the payee.
807 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
809 features: Option<Bolt12InvoiceFeatures>,
811 /// The recipient included these route hints in their BOLT11 invoice.
813 /// The node id of the payee.
815 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
816 route_hints: Vec<RouteHint>,
817 /// Features supported by the payee.
819 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
820 /// does not contain any features.
822 /// [`for_keysend`]: PaymentParameters::for_keysend
823 features: Option<Bolt11InvoiceFeatures>,
824 /// The minimum CLTV delta at the end of the route. This value must not be zero.
825 final_cltv_expiry_delta: u32,
830 fn node_id(&self) -> Option<PublicKey> {
832 Self::Clear { node_id, .. } => Some(*node_id),
836 fn node_features(&self) -> Option<NodeFeatures> {
838 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
839 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
842 fn supports_basic_mpp(&self) -> bool {
844 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
845 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
848 fn features(&self) -> Option<FeaturesRef> {
850 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
851 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
854 fn final_cltv_expiry_delta(&self) -> Option<u32> {
856 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
860 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
862 Self::Blinded { route_hints, .. } => &route_hints[..],
863 Self::Clear { .. } => &[]
867 fn unblinded_route_hints(&self) -> &[RouteHint] {
869 Self::Blinded { .. } => &[],
870 Self::Clear { route_hints, .. } => &route_hints[..]
875 enum FeaturesRef<'a> {
876 Bolt11(&'a Bolt11InvoiceFeatures),
877 Bolt12(&'a Bolt12InvoiceFeatures),
880 Bolt11(Bolt11InvoiceFeatures),
881 Bolt12(Bolt12InvoiceFeatures),
885 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
887 Self::Bolt12(f) => Some(f),
891 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
893 Self::Bolt11(f) => Some(f),
899 impl<'a> Writeable for FeaturesRef<'a> {
900 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
902 Self::Bolt11(f) => Ok(f.write(w)?),
903 Self::Bolt12(f) => Ok(f.write(w)?),
908 impl ReadableArgs<bool> for Features {
909 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
910 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
911 Ok(Self::Bolt12(Readable::read(reader)?))
915 /// A list of hops along a payment path terminating with a channel to the recipient.
916 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
917 pub struct RouteHint(pub Vec<RouteHintHop>);
919 impl Writeable for RouteHint {
920 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
921 (self.0.len() as u64).write(writer)?;
922 for hop in self.0.iter() {
929 impl Readable for RouteHint {
930 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
931 let hop_count: u64 = Readable::read(reader)?;
932 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
933 for _ in 0..hop_count {
934 hops.push(Readable::read(reader)?);
940 /// A channel descriptor for a hop along a payment path.
942 /// While this generally comes from BOLT 11's `r` field, this struct includes more fields than are
943 /// available in BOLT 11. Thus, encoding and decoding this via `lightning-invoice` is lossy, as
944 /// fields not supported in BOLT 11 will be stripped.
945 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
946 pub struct RouteHintHop {
947 /// The node_id of the non-target end of the route
948 pub src_node_id: PublicKey,
949 /// The short_channel_id of this channel
950 pub short_channel_id: u64,
951 /// The fees which must be paid to use this channel
952 pub fees: RoutingFees,
953 /// The difference in CLTV values between this node and the next node.
954 pub cltv_expiry_delta: u16,
955 /// The minimum value, in msat, which must be relayed to the next hop.
956 pub htlc_minimum_msat: Option<u64>,
957 /// The maximum value in msat available for routing with a single HTLC.
958 pub htlc_maximum_msat: Option<u64>,
961 impl_writeable_tlv_based!(RouteHintHop, {
962 (0, src_node_id, required),
963 (1, htlc_minimum_msat, option),
964 (2, short_channel_id, required),
965 (3, htlc_maximum_msat, option),
967 (6, cltv_expiry_delta, required),
970 #[derive(Eq, PartialEq)]
971 struct RouteGraphNode {
973 lowest_fee_to_node: u64,
974 total_cltv_delta: u32,
975 // The maximum value a yet-to-be-constructed payment path might flow through this node.
976 // This value is upper-bounded by us by:
977 // - how much is needed for a path being constructed
978 // - how much value can channels following this node (up to the destination) can contribute,
979 // considering their capacity and fees
980 value_contribution_msat: u64,
981 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
982 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
983 path_htlc_minimum_msat: u64,
984 /// All penalties incurred from this hop on the way to the destination, as calculated using
986 path_penalty_msat: u64,
987 /// The number of hops walked up to this node.
988 path_length_to_node: u8,
991 impl cmp::Ord for RouteGraphNode {
992 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
993 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
994 .saturating_add(other.path_penalty_msat);
995 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
996 .saturating_add(self.path_penalty_msat);
997 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
1001 impl cmp::PartialOrd for RouteGraphNode {
1002 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
1003 Some(self.cmp(other))
1007 /// A wrapper around the various hop representations.
1009 /// Can be used to examine the properties of a hop,
1010 /// potentially to decide whether to include it in a route.
1011 #[derive(Clone, Debug)]
1012 pub enum CandidateRouteHop<'a> {
1013 /// A hop from the payer, where the outbound liquidity is known.
1015 /// Channel details of the first hop
1017 /// [`ChannelDetails::get_outbound_payment_scid`] MUST be `Some` (indicating the channel
1018 /// has been funded and is able to pay), and accessor methods may panic otherwise.
1020 /// [`find_route`] validates this prior to constructing a [`CandidateRouteHop`].
1021 details: &'a ChannelDetails,
1022 /// The node id of the payer, which is also the source side of this candidate route hop.
1023 payer_node_id: &'a NodeId,
1025 /// A hop found in the [`ReadOnlyNetworkGraph`].
1027 /// Information about the channel, including potentially its capacity and
1028 /// direction-specific information.
1029 info: DirectedChannelInfo<'a>,
1030 /// The short channel ID of the channel, i.e. the identifier by which we refer to this
1032 short_channel_id: u64,
1034 /// A private hop communicated by the payee, generally via a BOLT 11 invoice.
1036 /// Because BOLT 11 route hints can take multiple hops to get to the destination, this may not
1037 /// terminate at the payee.
1039 /// Information about the private hop communicated via BOLT 11.
1040 hint: &'a RouteHintHop,
1041 /// Node id of the next hop in BOLT 11 route hint.
1042 target_node_id: NodeId
1044 /// A blinded path which starts with an introduction point and ultimately terminates with the
1047 /// Because we don't know the payee's identity, [`CandidateRouteHop::target`] will return
1048 /// `None` in this state.
1050 /// Because blinded paths are "all or nothing", and we cannot use just one part of a blinded
1051 /// path, the full path is treated as a single [`CandidateRouteHop`].
1053 /// Information about the blinded path including the fee, HTLC amount limits, and
1054 /// cryptographic material required to build an HTLC through the given path.
1055 hint: &'a (BlindedPayInfo, BlindedPath),
1056 /// Index of the hint in the original list of blinded hints.
1058 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1059 /// a short channel ID for this hop.
1062 /// Similar to [`Self::Blinded`], but the path here only has one hop.
1064 /// While we treat this similarly to [`CandidateRouteHop::Blinded`] in many respects (e.g.
1065 /// returning `None` from [`CandidateRouteHop::target`]), in this case we do actually know the
1066 /// payee's identity - it's the introduction point!
1068 /// [`BlindedPayInfo`] provided for 1-hop blinded paths is ignored because it is meant to apply
1069 /// to the hops *between* the introduction node and the destination.
1071 /// This primarily exists to track that we need to included a blinded path at the end of our
1072 /// [`Route`], even though it doesn't actually add an additional hop in the payment.
1074 /// Information about the blinded path including the fee, HTLC amount limits, and
1075 /// cryptographic material required to build an HTLC terminating with the given path.
1077 /// Note that the [`BlindedPayInfo`] is ignored here.
1078 hint: &'a (BlindedPayInfo, BlindedPath),
1079 /// Index of the hint in the original list of blinded hints.
1081 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1082 /// a short channel ID for this hop.
1087 impl<'a> CandidateRouteHop<'a> {
1088 /// Returns the short channel ID for this hop, if one is known.
1090 /// This SCID could be an alias or a globally unique SCID, and thus is only expected to
1091 /// uniquely identify this channel in conjunction with the [`CandidateRouteHop::source`].
1093 /// Returns `Some` as long as the candidate is a [`CandidateRouteHop::PublicHop`], a
1094 /// [`CandidateRouteHop::PrivateHop`] from a BOLT 11 route hint, or a
1095 /// [`CandidateRouteHop::FirstHop`] with a known [`ChannelDetails::get_outbound_payment_scid`]
1096 /// (which is always true for channels which are funded and ready for use).
1098 /// In other words, this should always return `Some` as long as the candidate hop is not a
1099 /// [`CandidateRouteHop::Blinded`] or a [`CandidateRouteHop::OneHopBlinded`].
1101 /// Note that this is deliberately not public as it is somewhat of a footgun because it doesn't
1102 /// define a global namespace.
1104 fn short_channel_id(&self) -> Option<u64> {
1106 CandidateRouteHop::FirstHop { details, .. } => details.get_outbound_payment_scid(),
1107 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1108 CandidateRouteHop::PrivateHop { hint, .. } => Some(hint.short_channel_id),
1109 CandidateRouteHop::Blinded { .. } => None,
1110 CandidateRouteHop::OneHopBlinded { .. } => None,
1114 /// Returns the globally unique short channel ID for this hop, if one is known.
1116 /// This only returns `Some` if the channel is public (either our own, or one we've learned
1117 /// from the public network graph), and thus the short channel ID we have for this channel is
1118 /// globally unique and identifies this channel in a global namespace.
1120 pub fn globally_unique_short_channel_id(&self) -> Option<u64> {
1122 CandidateRouteHop::FirstHop { details, .. } => if details.is_public { details.short_channel_id } else { None },
1123 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1124 CandidateRouteHop::PrivateHop { .. } => None,
1125 CandidateRouteHop::Blinded { .. } => None,
1126 CandidateRouteHop::OneHopBlinded { .. } => None,
1130 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1131 fn features(&self) -> ChannelFeatures {
1133 CandidateRouteHop::FirstHop { details, .. } => details.counterparty.features.to_context(),
1134 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1135 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1136 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1137 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1141 /// Returns cltv_expiry_delta for this hop.
1143 pub fn cltv_expiry_delta(&self) -> u32 {
1145 CandidateRouteHop::FirstHop { .. } => 0,
1146 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1147 CandidateRouteHop::PrivateHop { hint, .. } => hint.cltv_expiry_delta as u32,
1148 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1149 CandidateRouteHop::OneHopBlinded { .. } => 0,
1153 /// Returns the htlc_minimum_msat for this hop.
1155 pub fn htlc_minimum_msat(&self) -> u64 {
1157 CandidateRouteHop::FirstHop { details, .. } => details.next_outbound_htlc_minimum_msat,
1158 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1159 CandidateRouteHop::PrivateHop { hint, .. } => hint.htlc_minimum_msat.unwrap_or(0),
1160 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1161 CandidateRouteHop::OneHopBlinded { .. } => 0,
1165 /// Returns the fees for this hop.
1167 pub fn fees(&self) -> RoutingFees {
1169 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1170 base_msat: 0, proportional_millionths: 0,
1172 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1173 CandidateRouteHop::PrivateHop { hint, .. } => hint.fees,
1174 CandidateRouteHop::Blinded { hint, .. } => {
1176 base_msat: hint.0.fee_base_msat,
1177 proportional_millionths: hint.0.fee_proportional_millionths
1180 CandidateRouteHop::OneHopBlinded { .. } =>
1181 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1185 fn effective_capacity(&self) -> EffectiveCapacity {
1187 CandidateRouteHop::FirstHop { details, .. } => EffectiveCapacity::ExactLiquidity {
1188 liquidity_msat: details.next_outbound_htlc_limit_msat,
1190 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1191 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. } =>
1192 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1193 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. } =>
1194 EffectiveCapacity::Infinite,
1195 CandidateRouteHop::Blinded { hint, .. } =>
1196 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1197 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1201 /// Returns an ID describing the given hop.
1203 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1205 fn id(&self) -> CandidateHopId {
1207 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1208 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1209 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1212 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1214 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1220 /// Returns the source node id of current hop.
1222 /// Source node id refers to the hop forwarding the payment.
1224 /// For `FirstHop` we return payer's node id.
1226 pub fn source(&self) -> NodeId {
1228 CandidateRouteHop::FirstHop { payer_node_id, .. } => **payer_node_id,
1229 CandidateRouteHop::PublicHop { info, .. } => *info.source(),
1230 CandidateRouteHop::PrivateHop { hint, .. } => hint.src_node_id.into(),
1231 CandidateRouteHop::Blinded { hint, .. } => hint.1.introduction_node_id.into(),
1232 CandidateRouteHop::OneHopBlinded { hint, .. } => hint.1.introduction_node_id.into(),
1235 /// Returns the target node id of this hop, if known.
1237 /// Target node id refers to the hop receiving the payment.
1239 /// For `Blinded` and `OneHopBlinded` we return `None` because next hop is blinded.
1241 pub fn target(&self) -> Option<NodeId> {
1243 CandidateRouteHop::FirstHop { details, .. } => Some(details.counterparty.node_id.into()),
1244 CandidateRouteHop::PublicHop { info, .. } => Some(*info.target()),
1245 CandidateRouteHop::PrivateHop { target_node_id, .. } => Some(*target_node_id),
1246 CandidateRouteHop::Blinded { .. } => None,
1247 CandidateRouteHop::OneHopBlinded { .. } => None,
1252 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1254 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1256 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1257 /// isn't guaranteed to be unique at all.
1259 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1260 /// difficult-to-use API.
1261 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1262 enum CandidateHopId {
1263 /// Contains (scid, src_node_id < target_node_id)
1265 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1270 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1271 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1273 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1274 EffectiveCapacity::Infinite => u64::max_value(),
1275 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1276 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1277 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1278 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1279 // expected to have been generated from up-to-date capacity information.
1280 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1281 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1282 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1286 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1287 -> bool where I1::Item: PartialEq<I2::Item> {
1289 let a = iter_a.next();
1290 let b = iter_b.next();
1291 if a.is_none() && b.is_none() { return true; }
1292 if a.is_none() || b.is_none() { return false; }
1293 if a.unwrap().ne(&b.unwrap()) { return false; }
1297 /// It's useful to keep track of the hops associated with the fees required to use them,
1298 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1299 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1300 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1302 struct PathBuildingHop<'a> {
1303 candidate: CandidateRouteHop<'a>,
1306 /// All the fees paid *after* this channel on the way to the destination
1307 next_hops_fee_msat: u64,
1308 /// Fee paid for the use of the current channel (see candidate.fees()).
1309 /// The value will be actually deducted from the counterparty balance on the previous link.
1310 hop_use_fee_msat: u64,
1311 /// Used to compare channels when choosing the for routing.
1312 /// Includes paying for the use of a hop and the following hops, as well as
1313 /// an estimated cost of reaching this hop.
1314 /// Might get stale when fees are recomputed. Primarily for internal use.
1315 total_fee_msat: u64,
1316 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1317 /// walk and may be invalid thereafter.
1318 path_htlc_minimum_msat: u64,
1319 /// All penalties incurred from this channel on the way to the destination, as calculated using
1320 /// channel scoring.
1321 path_penalty_msat: u64,
1322 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1323 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1324 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1325 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1326 /// avoid processing them again.
1327 was_processed: bool,
1328 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1329 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1330 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1331 // value_contribution_msat, which requires tracking it here. See comments below where it is
1332 // used for more info.
1333 value_contribution_msat: u64,
1336 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1337 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1338 let mut debug_struct = f.debug_struct("PathBuildingHop");
1340 .field("node_id", &self.candidate.target())
1341 .field("short_channel_id", &self.candidate.short_channel_id())
1342 .field("total_fee_msat", &self.total_fee_msat)
1343 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1344 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1345 .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)))
1346 .field("path_penalty_msat", &self.path_penalty_msat)
1347 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1348 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1349 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1350 let debug_struct = debug_struct
1351 .field("value_contribution_msat", &self.value_contribution_msat);
1352 debug_struct.finish()
1356 // Instantiated with a list of hops with correct data in them collected during path finding,
1357 // an instance of this struct should be further modified only via given methods.
1359 struct PaymentPath<'a> {
1360 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1363 impl<'a> PaymentPath<'a> {
1364 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1365 fn get_value_msat(&self) -> u64 {
1366 self.hops.last().unwrap().0.fee_msat
1369 fn get_path_penalty_msat(&self) -> u64 {
1370 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1373 fn get_total_fee_paid_msat(&self) -> u64 {
1374 if self.hops.len() < 1 {
1378 // Can't use next_hops_fee_msat because it gets outdated.
1379 for (i, (hop, _)) in self.hops.iter().enumerate() {
1380 if i != self.hops.len() - 1 {
1381 result += hop.fee_msat;
1387 fn get_cost_msat(&self) -> u64 {
1388 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1391 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1392 // to change fees may result in an inconsistency.
1394 // Sometimes we call this function right after constructing a path which is inconsistent in
1395 // that it the value being transferred has decreased while we were doing path finding, leading
1396 // to the fees being paid not lining up with the actual limits.
1398 // Note that this function is not aware of the available_liquidity limit, and thus does not
1399 // support increasing the value being transferred beyond what was selected during the initial
1402 // Returns the amount that this path contributes to the total payment value, which may be greater
1403 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1404 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1405 let mut extra_contribution_msat = 0;
1406 let mut total_fee_paid_msat = 0 as u64;
1407 for i in (0..self.hops.len()).rev() {
1408 let last_hop = i == self.hops.len() - 1;
1410 // For non-last-hop, this value will represent the fees paid on the current hop. It
1411 // will consist of the fees for the use of the next hop, and extra fees to match
1412 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1413 let mut cur_hop_fees_msat = 0;
1415 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1418 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1419 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1420 cur_hop.path_penalty_msat += extra_contribution_msat;
1421 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1422 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1423 // set it too high just to maliciously take more fees by exploiting this
1424 // match htlc_minimum_msat logic.
1425 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1426 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1427 // Note that there is a risk that *previous hops* (those closer to us, as we go
1428 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1430 // This might make us end up with a broken route, although this should be super-rare
1431 // in practice, both because of how healthy channels look like, and how we pick
1432 // channels in add_entry.
1433 // Also, this can't be exploited more heavily than *announce a free path and fail
1435 cur_hop_transferred_amount_msat += extra_fees_msat;
1437 // We remember and return the extra fees on the final hop to allow accounting for
1438 // them in the path's value contribution.
1440 extra_contribution_msat = extra_fees_msat;
1442 total_fee_paid_msat += extra_fees_msat;
1443 cur_hop_fees_msat += extra_fees_msat;
1448 // Final hop is a special case: it usually has just value_msat (by design), but also
1449 // it still could overpay for the htlc_minimum_msat.
1450 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1452 // Propagate updated fees for the use of the channels to one hop back, where they
1453 // will be actually paid (fee_msat). The last hop is handled above separately.
1454 cur_hop.fee_msat = cur_hop_fees_msat;
1457 // Fee for the use of the current hop which will be deducted on the previous hop.
1458 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1459 // this channel is free for us.
1461 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1462 cur_hop.hop_use_fee_msat = new_fee;
1463 total_fee_paid_msat += new_fee;
1465 // It should not be possible because this function is called only to reduce the
1466 // value. In that case, compute_fee was already called with the same fees for
1467 // larger amount and there was no overflow.
1472 value_msat + extra_contribution_msat
1477 /// Calculate the fees required to route the given amount over a channel with the given fees.
1478 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1479 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1480 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1484 /// Calculate the fees required to route the given amount over a channel with the given fees,
1485 /// saturating to [`u64::max_value`].
1486 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1487 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1488 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1489 .saturating_add(channel_fees.base_msat as u64)
1492 /// The default `features` we assume for a node in a route, when no `features` are known about that
1495 /// Default features are:
1496 /// * variable_length_onion_optional
1497 fn default_node_features() -> NodeFeatures {
1498 let mut features = NodeFeatures::empty();
1499 features.set_variable_length_onion_optional();
1503 struct LoggedPayeePubkey(Option<PublicKey>);
1504 impl fmt::Display for LoggedPayeePubkey {
1505 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1508 "payee node id ".fmt(f)?;
1512 "blinded payee".fmt(f)
1518 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1519 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1520 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1522 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1523 "blinded route hint with introduction node id ".fmt(f)?;
1524 hint.1.introduction_node_id.fmt(f)?;
1525 " and blinding point ".fmt(f)?;
1526 hint.1.blinding_point.fmt(f)
1528 CandidateRouteHop::FirstHop { .. } => {
1529 "first hop with SCID ".fmt(f)?;
1530 self.0.short_channel_id().unwrap().fmt(f)
1532 CandidateRouteHop::PrivateHop { .. } => {
1533 "route hint with SCID ".fmt(f)?;
1534 self.0.short_channel_id().unwrap().fmt(f)
1538 self.0.short_channel_id().unwrap().fmt(f)
1545 fn sort_first_hop_channels(
1546 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1547 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1549 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1550 // most like to use.
1552 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1553 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1556 // Second, because simply always sorting in descending order would always use our largest
1557 // available outbound capacity, needlessly fragmenting our available channel capacities,
1558 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1559 // which have enough, but not too much, capacity for the payment.
1561 // Available outbound balances factor in liquidity already reserved for previously found paths.
1562 channels.sort_unstable_by(|chan_a, chan_b| {
1563 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1564 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1565 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1566 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1567 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1568 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1569 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1570 // Sort in descending order
1571 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1573 // Sort in ascending order
1574 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1579 /// Finds a route from us (payer) to the given target node (payee).
1581 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1582 /// in the given [`RouteParameters::payment_params`].
1583 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1585 /// Private routing paths between a public node and the target may be included in the `payee` field
1586 /// of [`RouteParameters::payment_params`].
1588 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1589 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1590 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1592 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1593 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1594 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1598 /// Panics if first_hops contains channels without `short_channel_id`s;
1599 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1601 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1602 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1603 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1604 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1605 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1606 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1607 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1608 ) -> Result<Route, LightningError>
1609 where L::Target: Logger, GL::Target: Logger {
1610 let graph_lock = network_graph.read_only();
1611 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1612 scorer, score_params, random_seed_bytes)?;
1613 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1617 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1618 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1619 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1620 _random_seed_bytes: &[u8; 32]
1621 ) -> Result<Route, LightningError>
1622 where L::Target: Logger {
1624 let payment_params = &route_params.payment_params;
1625 let final_value_msat = route_params.final_value_msat;
1626 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1627 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1628 // so use a dummy id for this in the blinded case.
1629 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1630 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1631 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1632 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1633 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1635 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1636 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1638 if our_node_id == maybe_dummy_payee_node_id {
1639 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1642 if final_value_msat > MAX_VALUE_MSAT {
1643 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1646 if final_value_msat == 0 {
1647 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1650 match &payment_params.payee {
1651 Payee::Clear { route_hints, node_id, .. } => {
1652 for route in route_hints.iter() {
1653 for hop in &route.0 {
1654 if hop.src_node_id == *node_id {
1655 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1660 Payee::Blinded { route_hints, .. } => {
1661 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1662 return Err(LightningError{err: "Cannot generate a route to blinded paths if we are the introduction node to all of them".to_owned(), action: ErrorAction::IgnoreError});
1664 for (_, blinded_path) in route_hints.iter() {
1665 if blinded_path.blinded_hops.len() == 0 {
1666 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1667 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1668 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1669 } else if blinded_path.blinded_hops.len() == 1 &&
1670 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1671 && p.introduction_node_id != blinded_path.introduction_node_id)
1673 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1678 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1679 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1680 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});
1683 // The general routing idea is the following:
1684 // 1. Fill first/last hops communicated by the caller.
1685 // 2. Attempt to construct a path from payer to payee for transferring
1686 // any ~sufficient (described later) value.
1687 // If succeed, remember which channels were used and how much liquidity they have available,
1688 // so that future paths don't rely on the same liquidity.
1689 // 3. Proceed to the next step if:
1690 // - we hit the recommended target value;
1691 // - OR if we could not construct a new path. Any next attempt will fail too.
1692 // Otherwise, repeat step 2.
1693 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1694 // (not recommended value).
1695 // 5. If yes, proceed. If not, fail routing.
1696 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1697 // transferred up to the transfer target value.
1698 // 7. Reduce the value of the last path until we are sending only the target value.
1699 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1700 // them so that we're not sending two HTLCs along the same path.
1702 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1703 // distance from the payee
1705 // We are not a faithful Dijkstra's implementation because we can change values which impact
1706 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1707 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1708 // the value we are currently attempting to send over a path, we simply reduce the value being
1709 // sent along the path for any hops after that channel. This may imply that later fees (which
1710 // we've already tabulated) are lower because a smaller value is passing through the channels
1711 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1712 // channels which were selected earlier (and which may still be used for other paths without a
1713 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1716 // One potentially problematic case for this algorithm would be if there are many
1717 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1718 // graph walking), we may never find a path which is not liquidity-limited and has lower
1719 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1720 // Because we only consider paths with at least 5% of the total value being sent, the damage
1721 // from such a case should be limited, however this could be further reduced in the future by
1722 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1723 // limits for the purposes of fee calculation.
1725 // Alternatively, we could store more detailed path information in the heap (targets, below)
1726 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1727 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1728 // and practically (as we would need to store dynamically-allocated path information in heap
1729 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1730 // results of such an algorithm would likely be biased towards lower-value paths.
1732 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1733 // outside of our current search value, running a path search more times to gather candidate
1734 // paths at different values. While this may be acceptable, further path searches may increase
1735 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1736 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1737 // the same time, remaining generic across different payment values.
1739 let network_channels = network_graph.channels();
1740 let network_nodes = network_graph.nodes();
1742 if payment_params.max_path_count == 0 {
1743 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1746 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1747 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1749 let allow_mpp = if payment_params.max_path_count == 1 {
1751 } else if payment_params.payee.supports_basic_mpp() {
1753 } else if let Some(payee) = payee_node_id_opt {
1754 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1755 |info| info.features.supports_basic_mpp()))
1758 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1760 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1761 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1762 if allow_mpp { "with" } else { "without" },
1763 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1764 max_total_routing_fee_msat);
1767 // Prepare the data we'll use for payee-to-payer search by
1768 // inserting first hops suggested by the caller as targets.
1769 // Our search will then attempt to reach them while traversing from the payee node.
1770 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1771 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1772 if let Some(hops) = first_hops {
1774 if chan.get_outbound_payment_scid().is_none() {
1775 panic!("first_hops should be filled in with usable channels, not pending ones");
1777 if chan.counterparty.node_id == *our_node_pubkey {
1778 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1781 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1782 .or_insert(Vec::new())
1785 if first_hop_targets.is_empty() {
1786 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1790 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1791 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1792 // adding duplicate entries when we find a better path to a given node.
1793 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1795 // Map from node_id to information about the best current path to that node, including feerate
1797 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1799 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1800 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1801 // htlc_minimum with extra fees while still finding a cheaper path.
1802 let mut hit_minimum_limit;
1804 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1805 // We start with a path_value of the exact amount we want, and if that generates a route we may
1806 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1807 // amount we want in total across paths, selecting the best subset at the end.
1808 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1809 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1810 let mut path_value_msat = final_value_msat;
1812 // Routing Fragmentation Mitigation heuristic:
1814 // Routing fragmentation across many payment paths increases the overall routing
1815 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1816 // Taking too many smaller paths also increases the chance of payment failure.
1817 // Thus to avoid this effect, we require from our collected links to provide
1818 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1819 // This requirement is currently set to be 1/max_path_count of the payment
1820 // value to ensure we only ever return routes that do not violate this limit.
1821 let minimal_value_contribution_msat: u64 = if allow_mpp {
1822 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1827 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1828 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1829 // drop the requirement by setting this to 0.
1830 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1832 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1833 // determine if the channel can be used by additional MPP paths or to inform path finding
1834 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1835 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1837 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1838 HashMap::with_capacity(network_nodes.len());
1840 // Keeping track of how much value we already collected across other paths. Helps to decide
1841 // when we want to stop looking for new paths.
1842 let mut already_collected_value_msat = 0;
1844 for (_, channels) in first_hop_targets.iter_mut() {
1845 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1849 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1850 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1852 // Remember how many candidates we ignored to allow for some logging afterwards.
1853 let mut num_ignored_value_contribution: u32 = 0;
1854 let mut num_ignored_path_length_limit: u32 = 0;
1855 let mut num_ignored_cltv_delta_limit: u32 = 0;
1856 let mut num_ignored_previously_failed: u32 = 0;
1857 let mut num_ignored_total_fee_limit: u32 = 0;
1858 let mut num_ignored_avoid_overpayment: u32 = 0;
1859 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
1861 macro_rules! add_entry {
1862 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
1863 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1864 // since that value has to be transferred over this channel.
1865 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1866 ( $candidate: expr, $next_hops_fee_msat: expr,
1867 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1868 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1869 // We "return" whether we updated the path at the end, and how much we can route via
1870 // this channel, via this:
1871 let mut hop_contribution_amt_msat = None;
1872 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1873 // practice these cases should be caught earlier:
1874 // - for regular channels at channel announcement (TODO)
1875 // - for first and last hops early in get_route
1876 let src_node_id = $candidate.source();
1877 if Some(src_node_id) != $candidate.target() {
1878 let scid_opt = $candidate.short_channel_id();
1879 let effective_capacity = $candidate.effective_capacity();
1880 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1882 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1883 // It may be misleading because we might later choose to reduce the value transferred
1884 // over these channels, and the channel which was insufficient might become sufficient.
1885 // Worst case: we drop a good channel here because it can't cover the high following
1886 // fees caused by one expensive channel, but then this channel could have been used
1887 // if the amount being transferred over this path is lower.
1888 // We do this for now, but this is a subject for removal.
1889 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1890 let used_liquidity_msat = used_liquidities
1891 .get(&$candidate.id())
1892 .map_or(0, |used_liquidity_msat| {
1893 available_value_contribution_msat = available_value_contribution_msat
1894 .saturating_sub(*used_liquidity_msat);
1895 *used_liquidity_msat
1898 // Verify the liquidity offered by this channel complies to the minimal contribution.
1899 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1900 // Do not consider candidate hops that would exceed the maximum path length.
1901 let path_length_to_node = $next_hops_path_length + 1;
1902 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1904 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1905 // In order to already account for some of the privacy enhancing random CLTV
1906 // expiry delta offset we add on top later, we subtract a rough estimate
1907 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1908 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1909 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1910 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1911 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1912 .saturating_add($candidate.cltv_expiry_delta());
1913 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1915 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1916 // Includes paying fees for the use of the following channels.
1917 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1918 Some(result) => result,
1919 // Can't overflow due to how the values were computed right above.
1920 None => unreachable!(),
1922 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1923 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1924 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1926 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1927 let may_overpay_to_meet_path_minimum_msat =
1928 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1929 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
1930 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1931 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
1933 let payment_failed_on_this_channel = scid_opt.map_or(false,
1934 |scid| payment_params.previously_failed_channels.contains(&scid));
1936 let (should_log_candidate, first_hop_details) = match $candidate {
1937 CandidateRouteHop::FirstHop { details, .. } => (true, Some(details)),
1938 CandidateRouteHop::PrivateHop { .. } => (true, None),
1939 CandidateRouteHop::Blinded { .. } => (true, None),
1940 CandidateRouteHop::OneHopBlinded { .. } => (true, None),
1944 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1945 // bother considering this channel. If retrying with recommended_value_msat may
1946 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1947 // around again with a higher amount.
1948 if !contributes_sufficient_value {
1949 if should_log_candidate {
1950 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1952 if let Some(details) = first_hop_details {
1954 "First hop candidate next_outbound_htlc_limit_msat: {}",
1955 details.next_outbound_htlc_limit_msat,
1959 num_ignored_value_contribution += 1;
1960 } else if exceeds_max_path_length {
1961 if should_log_candidate {
1962 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1964 num_ignored_path_length_limit += 1;
1965 } else if exceeds_cltv_delta_limit {
1966 if should_log_candidate {
1967 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1969 if let Some(_) = first_hop_details {
1971 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
1972 hop_total_cltv_delta,
1973 max_total_cltv_expiry_delta,
1977 num_ignored_cltv_delta_limit += 1;
1978 } else if payment_failed_on_this_channel {
1979 if should_log_candidate {
1980 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1982 num_ignored_previously_failed += 1;
1983 } else if may_overpay_to_meet_path_minimum_msat {
1984 if should_log_candidate {
1986 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
1987 LoggedCandidateHop(&$candidate));
1989 if let Some(details) = first_hop_details {
1991 "First hop candidate next_outbound_htlc_minimum_msat: {}",
1992 details.next_outbound_htlc_minimum_msat,
1996 num_ignored_avoid_overpayment += 1;
1997 hit_minimum_limit = true;
1998 } else if over_path_minimum_msat {
1999 // Note that low contribution here (limited by available_liquidity_msat)
2000 // might violate htlc_minimum_msat on the hops which are next along the
2001 // payment path (upstream to the payee). To avoid that, we recompute
2002 // path fees knowing the final path contribution after constructing it.
2003 let curr_min = cmp::max(
2004 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2006 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2007 .saturating_add(curr_min);
2008 let hm_entry = dist.entry(src_node_id);
2009 let old_entry = hm_entry.or_insert_with(|| {
2010 // If there was previously no known way to access the source node
2011 // (recall it goes payee-to-payer) of short_channel_id, first add a
2012 // semi-dummy record just to compute the fees to reach the source node.
2013 // This will affect our decision on selecting short_channel_id
2014 // as a way to reach the $candidate.target() node.
2016 candidate: $candidate.clone(),
2018 next_hops_fee_msat: u64::max_value(),
2019 hop_use_fee_msat: u64::max_value(),
2020 total_fee_msat: u64::max_value(),
2021 path_htlc_minimum_msat,
2022 path_penalty_msat: u64::max_value(),
2023 was_processed: false,
2024 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2025 value_contribution_msat,
2029 #[allow(unused_mut)] // We only use the mut in cfg(test)
2030 let mut should_process = !old_entry.was_processed;
2031 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2033 // In test/fuzzing builds, we do extra checks to make sure the skipping
2034 // of already-seen nodes only happens in cases we expect (see below).
2035 if !should_process { should_process = true; }
2039 let mut hop_use_fee_msat = 0;
2040 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2042 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2043 // will have the same effective-fee
2044 if src_node_id != our_node_id {
2045 // Note that `u64::max_value` means we'll always fail the
2046 // `old_entry.total_fee_msat > total_fee_msat` check below
2047 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2048 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2051 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2052 if total_fee_msat > max_total_routing_fee_msat {
2053 if should_log_candidate {
2054 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2056 if let Some(_) = first_hop_details {
2058 "First hop candidate routing fee: {}. Limit: {}",
2060 max_total_routing_fee_msat,
2064 num_ignored_total_fee_limit += 1;
2066 let channel_usage = ChannelUsage {
2067 amount_msat: amount_to_transfer_over_msat,
2068 inflight_htlc_msat: used_liquidity_msat,
2071 let channel_penalty_msat =
2072 scorer.channel_penalty_msat($candidate,
2075 let path_penalty_msat = $next_hops_path_penalty_msat
2076 .saturating_add(channel_penalty_msat);
2077 let new_graph_node = RouteGraphNode {
2078 node_id: src_node_id,
2079 lowest_fee_to_node: total_fee_msat,
2080 total_cltv_delta: hop_total_cltv_delta,
2081 value_contribution_msat,
2082 path_htlc_minimum_msat,
2084 path_length_to_node,
2087 // Update the way of reaching $candidate.source()
2088 // with the given short_channel_id (from $candidate.target()),
2089 // if this way is cheaper than the already known
2090 // (considering the cost to "reach" this channel from the route destination,
2091 // the cost of using this channel,
2092 // and the cost of routing to the source node of this channel).
2093 // Also, consider that htlc_minimum_msat_difference, because we might end up
2094 // paying it. Consider the following exploit:
2095 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2096 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2097 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2098 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2100 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2101 // but it may require additional tracking - we don't want to double-count
2102 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2103 // can't use something that may decrease on future hops.
2104 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2105 .saturating_add(old_entry.path_penalty_msat);
2106 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2107 .saturating_add(path_penalty_msat);
2109 if !old_entry.was_processed && new_cost < old_cost {
2110 targets.push(new_graph_node);
2111 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2112 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2113 old_entry.total_fee_msat = total_fee_msat;
2114 old_entry.candidate = $candidate.clone();
2115 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2116 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2117 old_entry.path_penalty_msat = path_penalty_msat;
2118 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2120 old_entry.value_contribution_msat = value_contribution_msat;
2122 hop_contribution_amt_msat = Some(value_contribution_msat);
2123 } else if old_entry.was_processed && new_cost < old_cost {
2124 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2126 // If we're skipping processing a node which was previously
2127 // processed even though we found another path to it with a
2128 // cheaper fee, check that it was because the second path we
2129 // found (which we are processing now) has a lower value
2130 // contribution due to an HTLC minimum limit.
2132 // e.g. take a graph with two paths from node 1 to node 2, one
2133 // through channel A, and one through channel B. Channel A and
2134 // B are both in the to-process heap, with their scores set by
2135 // a higher htlc_minimum than fee.
2136 // Channel A is processed first, and the channels onwards from
2137 // node 1 are added to the to-process heap. Thereafter, we pop
2138 // Channel B off of the heap, note that it has a much more
2139 // restrictive htlc_maximum_msat, and recalculate the fees for
2140 // all of node 1's channels using the new, reduced, amount.
2142 // This would be bogus - we'd be selecting a higher-fee path
2143 // with a lower htlc_maximum_msat instead of the one we'd
2144 // already decided to use.
2145 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2147 value_contribution_msat + path_penalty_msat <
2148 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2155 if should_log_candidate {
2157 "Ignoring {} due to its htlc_minimum_msat limit.",
2158 LoggedCandidateHop(&$candidate));
2160 if let Some(details) = first_hop_details {
2162 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2163 details.next_outbound_htlc_minimum_msat,
2167 num_ignored_htlc_minimum_msat_limit += 1;
2171 hop_contribution_amt_msat
2175 let default_node_features = default_node_features();
2177 // Find ways (channels with destination) to reach a given node and store them
2178 // in the corresponding data structures (routing graph etc).
2179 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2180 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2181 // This data can later be helpful to optimize routing (pay lower fees).
2182 macro_rules! add_entries_to_cheapest_to_target_node {
2183 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
2184 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
2185 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2186 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2187 let was_processed = elem.was_processed;
2188 elem.was_processed = true;
2191 // Entries are added to dist in add_entry!() when there is a channel from a node.
2192 // Because there are no channels from payee, it will not have a dist entry at this point.
2193 // If we're processing any other node, it is always be the result of a channel from it.
2194 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2199 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2200 for details in first_channels {
2201 let candidate = CandidateRouteHop::FirstHop {
2202 details, payer_node_id: &our_node_id,
2204 add_entry!(&candidate, $fee_to_target_msat,
2205 $next_hops_value_contribution,
2206 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
2207 $next_hops_cltv_delta, $next_hops_path_length);
2211 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2214 &default_node_features
2217 if !features.requires_unknown_bits() {
2218 for chan_id in $node.channels.iter() {
2219 let chan = network_channels.get(chan_id).unwrap();
2220 if !chan.features.requires_unknown_bits() {
2221 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2222 if first_hops.is_none() || *source != our_node_id {
2223 if directed_channel.direction().enabled {
2224 let candidate = CandidateRouteHop::PublicHop {
2225 info: directed_channel,
2226 short_channel_id: *chan_id,
2228 add_entry!(&candidate,
2229 $fee_to_target_msat,
2230 $next_hops_value_contribution,
2231 $next_hops_path_htlc_minimum_msat,
2232 $next_hops_path_penalty_msat,
2233 $next_hops_cltv_delta, $next_hops_path_length);
2244 let mut payment_paths = Vec::<PaymentPath>::new();
2246 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2247 'paths_collection: loop {
2248 // For every new path, start from scratch, except for used_liquidities, which
2249 // helps to avoid reusing previously selected paths in future iterations.
2252 hit_minimum_limit = false;
2254 // If first hop is a private channel and the only way to reach the payee, this is the only
2255 // place where it could be added.
2256 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2257 for details in first_channels {
2258 let candidate = CandidateRouteHop::FirstHop {
2259 details, payer_node_id: &our_node_id,
2261 let added = add_entry!(&candidate, 0, path_value_msat,
2262 0, 0u64, 0, 0).is_some();
2263 log_trace!(logger, "{} direct route to payee via {}",
2264 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2268 // Add the payee as a target, so that the payee-to-payer
2269 // search algorithm knows what to start with.
2270 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2271 // The payee is not in our network graph, so nothing to add here.
2272 // There is still a chance of reaching them via last_hops though,
2273 // so don't yet fail the payment here.
2274 // If not, targets.pop() will not even let us enter the loop in step 2.
2277 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2282 // If a caller provided us with last hops, add them to routing targets. Since this happens
2283 // earlier than general path finding, they will be somewhat prioritized, although currently
2284 // it matters only if the fees are exactly the same.
2285 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2286 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2287 let have_intro_node_in_graph =
2288 // Only add the hops in this route to our candidate set if either
2289 // we have a direct channel to the first hop or the first hop is
2290 // in the regular network graph.
2291 first_hop_targets.get(&intro_node_id).is_some() ||
2292 network_nodes.get(&intro_node_id).is_some();
2293 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2294 let candidate = if hint.1.blinded_hops.len() == 1 {
2295 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2296 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2297 let mut path_contribution_msat = path_value_msat;
2298 if let Some(hop_used_msat) = add_entry!(&candidate,
2299 0, path_contribution_msat, 0, 0_u64, 0, 0)
2301 path_contribution_msat = hop_used_msat;
2303 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2304 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2306 for details in first_channels {
2307 let first_hop_candidate = CandidateRouteHop::FirstHop {
2308 details, payer_node_id: &our_node_id,
2310 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2314 let path_min = candidate.htlc_minimum_msat().saturating_add(
2315 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2316 add_entry!(&first_hop_candidate, blinded_path_fee,
2317 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2318 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2322 for route in payment_params.payee.unblinded_route_hints().iter()
2323 .filter(|route| !route.0.is_empty())
2325 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2326 let first_hop_src_is_reachable =
2327 // Only add the hops in this route to our candidate set if either we are part of
2328 // the first hop, we have a direct channel to the first hop, or the first hop is in
2329 // the regular network graph.
2330 our_node_id == first_hop_src_id ||
2331 first_hop_targets.get(&first_hop_src_id).is_some() ||
2332 network_nodes.get(&first_hop_src_id).is_some();
2333 if first_hop_src_is_reachable {
2334 // We start building the path from reverse, i.e., from payee
2335 // to the first RouteHintHop in the path.
2336 let hop_iter = route.0.iter().rev();
2337 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2338 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2339 let mut hop_used = true;
2340 let mut aggregate_next_hops_fee_msat: u64 = 0;
2341 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2342 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2343 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2344 let mut aggregate_next_hops_path_length: u8 = 0;
2345 let mut aggregate_path_contribution_msat = path_value_msat;
2347 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2348 let source = NodeId::from_pubkey(&hop.src_node_id);
2349 let target = NodeId::from_pubkey(&prev_hop_id);
2351 if let Some(first_channels) = first_hop_targets.get(&target) {
2352 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2353 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2354 hop.short_channel_id);
2359 let candidate = network_channels
2360 .get(&hop.short_channel_id)
2361 .and_then(|channel| channel.as_directed_to(&target))
2362 .map(|(info, _)| CandidateRouteHop::PublicHop {
2364 short_channel_id: hop.short_channel_id,
2366 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop, target_node_id: target });
2368 if let Some(hop_used_msat) = add_entry!(&candidate,
2369 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2370 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2371 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2373 aggregate_path_contribution_msat = hop_used_msat;
2375 // If this hop was not used then there is no use checking the preceding
2376 // hops in the RouteHint. We can break by just searching for a direct
2377 // channel between last checked hop and first_hop_targets.
2381 let used_liquidity_msat = used_liquidities
2382 .get(&candidate.id()).copied()
2384 let channel_usage = ChannelUsage {
2385 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2386 inflight_htlc_msat: used_liquidity_msat,
2387 effective_capacity: candidate.effective_capacity(),
2389 let channel_penalty_msat = scorer.channel_penalty_msat(
2390 &candidate, channel_usage, score_params
2392 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2393 .saturating_add(channel_penalty_msat);
2395 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2396 .saturating_add(hop.cltv_expiry_delta as u32);
2398 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2401 // Searching for a direct channel between last checked hop and first_hop_targets
2402 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2403 sort_first_hop_channels(first_channels, &used_liquidities,
2404 recommended_value_msat, our_node_pubkey);
2405 for details in first_channels {
2406 let first_hop_candidate = CandidateRouteHop::FirstHop {
2407 details, payer_node_id: &our_node_id,
2409 add_entry!(&first_hop_candidate,
2410 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2411 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2412 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2420 // In the next values of the iterator, the aggregate fees already reflects
2421 // the sum of value sent from payer (final_value_msat) and routing fees
2422 // for the last node in the RouteHint. We need to just add the fees to
2423 // route through the current node so that the preceding node (next iteration)
2425 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2426 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2427 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2429 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2430 // this route hint's source node to forward said min over this channel.
2431 aggregate_next_hops_path_htlc_minimum_msat = {
2432 let curr_htlc_min = cmp::max(
2433 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2435 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2436 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2439 if idx == route.0.len() - 1 {
2440 // The last hop in this iterator is the first hop in
2441 // overall RouteHint.
2442 // If this hop connects to a node with which we have a direct channel,
2443 // ignore the network graph and, if the last hop was added, add our
2444 // direct channel to the candidate set.
2446 // Note that we *must* check if the last hop was added as `add_entry`
2447 // always assumes that the third argument is a node to which we have a
2449 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2450 sort_first_hop_channels(first_channels, &used_liquidities,
2451 recommended_value_msat, our_node_pubkey);
2452 for details in first_channels {
2453 let first_hop_candidate = CandidateRouteHop::FirstHop {
2454 details, payer_node_id: &our_node_id,
2456 add_entry!(&first_hop_candidate,
2457 aggregate_next_hops_fee_msat,
2458 aggregate_path_contribution_msat,
2459 aggregate_next_hops_path_htlc_minimum_msat,
2460 aggregate_next_hops_path_penalty_msat,
2461 aggregate_next_hops_cltv_delta,
2462 aggregate_next_hops_path_length);
2470 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2472 // At this point, targets are filled with the data from first and
2473 // last hops communicated by the caller, and the payment receiver.
2474 let mut found_new_path = false;
2477 // If this loop terminates due the exhaustion of targets, two situations are possible:
2478 // - not enough outgoing liquidity:
2479 // 0 < already_collected_value_msat < final_value_msat
2480 // - enough outgoing liquidity:
2481 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2482 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2483 // paths_collection will be stopped because found_new_path==false.
2484 // This is not necessarily a routing failure.
2485 '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() {
2487 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2488 // traversing the graph and arrange the path out of what we found.
2489 if node_id == our_node_id {
2490 let mut new_entry = dist.remove(&our_node_id).unwrap();
2491 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2494 let mut features_set = false;
2495 let target = ordered_hops.last().unwrap().0.candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2496 if let Some(first_channels) = first_hop_targets.get(&target) {
2497 for details in first_channels {
2498 if let CandidateRouteHop::FirstHop { details: last_hop_details, .. }
2499 = ordered_hops.last().unwrap().0.candidate
2501 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2502 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2503 features_set = true;
2510 if let Some(node) = network_nodes.get(&target) {
2511 if let Some(node_info) = node.announcement_info.as_ref() {
2512 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2514 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2517 // We can fill in features for everything except hops which were
2518 // provided via the invoice we're paying. We could guess based on the
2519 // recipient's features but for now we simply avoid guessing at all.
2523 // Means we succesfully traversed from the payer to the payee, now
2524 // save this path for the payment route. Also, update the liquidity
2525 // remaining on the used hops, so that we take them into account
2526 // while looking for more paths.
2527 if target == maybe_dummy_payee_node_id {
2531 new_entry = match dist.remove(&target) {
2532 Some(payment_hop) => payment_hop,
2533 // We can't arrive at None because, if we ever add an entry to targets,
2534 // we also fill in the entry in dist (see add_entry!).
2535 None => unreachable!(),
2537 // We "propagate" the fees one hop backward (topologically) here,
2538 // so that fees paid for a HTLC forwarding on the current channel are
2539 // associated with the previous channel (where they will be subtracted).
2540 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2541 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2543 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2544 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2546 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2547 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2549 let mut payment_path = PaymentPath {hops: ordered_hops};
2551 // We could have possibly constructed a slightly inconsistent path: since we reduce
2552 // value being transferred along the way, we could have violated htlc_minimum_msat
2553 // on some channels we already passed (assuming dest->source direction). Here, we
2554 // recompute the fees again, so that if that's the case, we match the currently
2555 // underpaid htlc_minimum_msat with fees.
2556 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2557 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2558 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2560 // Since a path allows to transfer as much value as
2561 // the smallest channel it has ("bottleneck"), we should recompute
2562 // the fees so sender HTLC don't overpay fees when traversing
2563 // larger channels than the bottleneck. This may happen because
2564 // when we were selecting those channels we were not aware how much value
2565 // this path will transfer, and the relative fee for them
2566 // might have been computed considering a larger value.
2567 // Remember that we used these channels so that we don't rely
2568 // on the same liquidity in future paths.
2569 let mut prevented_redundant_path_selection = false;
2570 for (hop, _) in payment_path.hops.iter() {
2571 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2572 let used_liquidity_msat = used_liquidities
2573 .entry(hop.candidate.id())
2574 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2575 .or_insert(spent_on_hop_msat);
2576 let hop_capacity = hop.candidate.effective_capacity();
2577 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2578 if *used_liquidity_msat == hop_max_msat {
2579 // If this path used all of this channel's available liquidity, we know
2580 // this path will not be selected again in the next loop iteration.
2581 prevented_redundant_path_selection = true;
2583 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2585 if !prevented_redundant_path_selection {
2586 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2587 // we'll probably end up picking the same path again on the next iteration.
2588 // Decrease the available liquidity of a hop in the middle of the path.
2589 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2590 let exhausted = u64::max_value();
2592 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2593 LoggedCandidateHop(victim_candidate));
2594 if let Some(scid) = victim_candidate.short_channel_id() {
2595 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2596 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2600 // Track the total amount all our collected paths allow to send so that we know
2601 // when to stop looking for more paths
2602 already_collected_value_msat += value_contribution_msat;
2604 payment_paths.push(payment_path);
2605 found_new_path = true;
2606 break 'path_construction;
2609 // If we found a path back to the payee, we shouldn't try to process it again. This is
2610 // the equivalent of the `elem.was_processed` check in
2611 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2612 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2614 // Otherwise, since the current target node is not us,
2615 // keep "unrolling" the payment graph from payee to payer by
2616 // finding a way to reach the current target from the payer side.
2617 match network_nodes.get(&node_id) {
2620 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2621 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2622 total_cltv_delta, path_length_to_node);
2628 if !found_new_path && channel_saturation_pow_half != 0 {
2629 channel_saturation_pow_half = 0;
2630 continue 'paths_collection;
2632 // If we don't support MPP, no use trying to gather more value ever.
2633 break 'paths_collection;
2637 // Stop either when the recommended value is reached or if no new path was found in this
2639 // In the latter case, making another path finding attempt won't help,
2640 // because we deterministically terminated the search due to low liquidity.
2641 if !found_new_path && channel_saturation_pow_half != 0 {
2642 channel_saturation_pow_half = 0;
2643 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2644 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2645 path_value_msat = recommended_value_msat;
2646 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2647 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2648 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2649 break 'paths_collection;
2650 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2651 // Further, if this was our first walk of the graph, and we weren't limited by an
2652 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2653 // limited by an htlc_minimum_msat value, find another path with a higher value,
2654 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2655 // still keeping a lower total fee than this path.
2656 if !hit_minimum_limit {
2657 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2658 break 'paths_collection;
2660 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher value to meet htlc_minimum_msat limit.");
2661 path_value_msat = recommended_value_msat;
2665 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2666 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2667 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2668 num_ignored_total_fee_limit;
2669 if num_ignored_total > 0 {
2671 "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure, {} due to htlc_minimum_msat limit, {} to avoid overpaying, {} due to maximum total fee limit. Total: {} ignored candidates.",
2672 num_ignored_value_contribution, num_ignored_path_length_limit,
2673 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2674 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2675 num_ignored_total_fee_limit, num_ignored_total);
2679 if payment_paths.len() == 0 {
2680 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2683 if already_collected_value_msat < final_value_msat {
2684 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2688 let mut selected_route = payment_paths;
2690 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2691 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2693 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2694 // the value they contribute towards the payment amount.
2695 // We sort in descending order as we will remove from the front in `retain`, next.
2696 selected_route.sort_unstable_by(|a, b|
2697 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2698 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2701 // We should make sure that at least 1 path left.
2702 let mut paths_left = selected_route.len();
2703 selected_route.retain(|path| {
2704 if paths_left == 1 {
2707 let path_value_msat = path.get_value_msat();
2708 if path_value_msat <= overpaid_value_msat {
2709 overpaid_value_msat -= path_value_msat;
2715 debug_assert!(selected_route.len() > 0);
2717 if overpaid_value_msat != 0 {
2719 // Now, subtract the remaining overpaid value from the most-expensive path.
2720 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2721 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2722 selected_route.sort_unstable_by(|a, b| {
2723 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2724 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2725 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2727 let expensive_payment_path = selected_route.first_mut().unwrap();
2729 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2730 // can't go negative.
2731 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2732 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2736 // Sort by the path itself and combine redundant paths.
2737 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2738 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2740 selected_route.sort_unstable_by_key(|path| {
2741 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2742 debug_assert!(path.hops.len() <= key.len());
2743 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
2748 for idx in 0..(selected_route.len() - 1) {
2749 if idx + 1 >= selected_route.len() { break; }
2750 if iter_equal(selected_route[idx].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
2751 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
2752 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2753 selected_route[idx].update_value_and_recompute_fees(new_value);
2754 selected_route.remove(idx + 1);
2758 let mut paths = Vec::new();
2759 for payment_path in selected_route {
2760 let mut hops = Vec::with_capacity(payment_path.hops.len());
2761 for (hop, node_features) in payment_path.hops.iter()
2762 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2764 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
2765 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2766 // If we sourced the hop from the graph we're sure the target node is announced.
2768 } else if let CandidateRouteHop::FirstHop { details, .. } = hop.candidate {
2769 // If this is a first hop we also know if it's announced.
2772 // If we sourced it any other way, we double-check the network graph to see if
2773 // there are announced channels between the endpoints. If so, the hop might be
2774 // referring to any of the announced channels, as its `short_channel_id` might be
2775 // an alias, in which case we don't take any chances here.
2776 network_graph.node(&target).map_or(false, |hop_node|
2777 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2778 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
2782 hops.push(RouteHop {
2783 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2784 node_features: node_features.clone(),
2785 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2786 channel_features: hop.candidate.features(),
2787 fee_msat: hop.fee_msat,
2788 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2789 maybe_announced_channel,
2792 let mut final_cltv_delta = final_cltv_expiry_delta;
2793 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2794 if let Some(blinded_path) = h.candidate.blinded_path() {
2795 final_cltv_delta = h.candidate.cltv_expiry_delta();
2797 hops: blinded_path.blinded_hops.clone(),
2798 blinding_point: blinded_path.blinding_point,
2799 excess_final_cltv_expiry_delta: 0,
2800 final_value_msat: h.fee_msat,
2804 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2805 // applicable for the previous hop.
2806 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2807 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2810 paths.push(Path { hops, blinded_tail });
2812 // Make sure we would never create a route with more paths than we allow.
2813 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2815 if let Some(node_features) = payment_params.payee.node_features() {
2816 for path in paths.iter_mut() {
2817 path.hops.last_mut().unwrap().node_features = node_features.clone();
2821 let route = Route { paths, route_params: Some(route_params.clone()) };
2823 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2824 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2825 if route.get_total_fees() > max_total_routing_fee_msat {
2826 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2827 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2831 log_info!(logger, "Got route: {}", log_route!(route));
2835 // When an adversarial intermediary node observes a payment, it may be able to infer its
2836 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2837 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2838 // payment path by adding a randomized 'shadow route' offset to the final hop.
2839 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2840 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2842 let network_channels = network_graph.channels();
2843 let network_nodes = network_graph.nodes();
2845 for path in route.paths.iter_mut() {
2846 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2848 // Remember the last three nodes of the random walk and avoid looping back on them.
2849 // Init with the last three nodes from the actual path, if possible.
2850 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2851 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2852 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2854 // Choose the last publicly known node as the starting point for the random walk.
2855 let mut cur_hop: Option<NodeId> = None;
2856 let mut path_nonce = [0u8; 12];
2857 if let Some(starting_hop) = path.hops.iter().rev()
2858 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2859 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2860 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2863 // Init PRNG with the path-dependant nonce, which is static for private paths.
2864 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2865 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2867 // Pick a random path length in [1 .. 3]
2868 prng.process_in_place(&mut random_path_bytes);
2869 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2871 for random_hop in 0..random_walk_length {
2872 // If we don't find a suitable offset in the public network graph, we default to
2873 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2874 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2876 if let Some(cur_node_id) = cur_hop {
2877 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2878 // Randomly choose the next unvisited hop.
2879 prng.process_in_place(&mut random_path_bytes);
2880 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2881 .checked_rem(cur_node.channels.len())
2882 .and_then(|index| cur_node.channels.get(index))
2883 .and_then(|id| network_channels.get(id)) {
2884 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2885 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2886 nodes_to_avoid[random_hop] = *next_id;
2887 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2888 cur_hop = Some(*next_id);
2895 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2896 .checked_add(random_hop_offset)
2897 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2900 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2901 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2902 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2904 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2905 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2906 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2907 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2908 max_path_offset = cmp::max(
2909 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2910 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2911 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2913 // Add 'shadow' CLTV offset to the final hop
2914 if let Some(tail) = path.blinded_tail.as_mut() {
2915 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2916 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2918 if let Some(last_hop) = path.hops.last_mut() {
2919 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2920 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2925 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2926 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2928 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2929 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2930 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2931 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2932 ) -> Result<Route, LightningError>
2933 where L::Target: Logger, GL::Target: Logger {
2934 let graph_lock = network_graph.read_only();
2935 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2936 &graph_lock, logger, random_seed_bytes)?;
2937 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2941 fn build_route_from_hops_internal<L: Deref>(
2942 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2943 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2944 ) -> Result<Route, LightningError> where L::Target: Logger {
2947 our_node_id: NodeId,
2948 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2951 impl ScoreLookUp for HopScorer {
2952 type ScoreParams = ();
2953 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
2954 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2956 let mut cur_id = self.our_node_id;
2957 for i in 0..self.hop_ids.len() {
2958 if let Some(next_id) = self.hop_ids[i] {
2959 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
2971 impl<'a> Writeable for HopScorer {
2973 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2978 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2979 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2982 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2983 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2984 for i in 0..hops.len() {
2985 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2988 let scorer = HopScorer { our_node_id, hop_ids };
2990 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
2995 use crate::blinded_path::{BlindedHop, BlindedPath};
2996 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2997 use crate::routing::utxo::UtxoResult;
2998 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2999 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3000 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop};
3001 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3002 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3003 use crate::chain::transaction::OutPoint;
3004 use crate::sign::EntropySource;
3005 use crate::ln::ChannelId;
3006 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3007 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3008 use crate::ln::channelmanager;
3009 use crate::offers::invoice::BlindedPayInfo;
3010 use crate::util::config::UserConfig;
3011 use crate::util::test_utils as ln_test_utils;
3012 use crate::util::chacha20::ChaCha20;
3013 use crate::util::ser::{Readable, Writeable};
3015 use crate::util::ser::Writer;
3017 use bitcoin::hashes::Hash;
3018 use bitcoin::network::constants::Network;
3019 use bitcoin::blockdata::constants::ChainHash;
3020 use bitcoin::blockdata::script::Builder;
3021 use bitcoin::blockdata::opcodes;
3022 use bitcoin::blockdata::transaction::TxOut;
3023 use bitcoin::hashes::hex::FromHex;
3024 use bitcoin::secp256k1::{PublicKey,SecretKey};
3025 use bitcoin::secp256k1::Secp256k1;
3027 use crate::io::Cursor;
3028 use crate::prelude::*;
3029 use crate::sync::Arc;
3031 use core::convert::TryInto;
3033 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3034 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
3035 channelmanager::ChannelDetails {
3036 channel_id: ChannelId::new_zero(),
3037 counterparty: channelmanager::ChannelCounterparty {
3040 unspendable_punishment_reserve: 0,
3041 forwarding_info: None,
3042 outbound_htlc_minimum_msat: None,
3043 outbound_htlc_maximum_msat: None,
3045 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3048 outbound_scid_alias: None,
3049 inbound_scid_alias: None,
3050 channel_value_satoshis: 0,
3053 outbound_capacity_msat,
3054 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3055 next_outbound_htlc_minimum_msat: 0,
3056 inbound_capacity_msat: 42,
3057 unspendable_punishment_reserve: None,
3058 confirmations_required: None,
3059 confirmations: None,
3060 force_close_spend_delay: None,
3061 is_outbound: true, is_channel_ready: true,
3062 is_usable: true, is_public: true,
3063 inbound_htlc_minimum_msat: None,
3064 inbound_htlc_maximum_msat: None,
3066 feerate_sat_per_1000_weight: None,
3067 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
3072 fn simple_route_test() {
3073 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3074 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3075 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3076 let scorer = ln_test_utils::TestScorer::new();
3077 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3078 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3080 // Simple route to 2 via 1
3082 let route_params = RouteParameters::from_payment_params_and_value(
3083 payment_params.clone(), 0);
3084 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3085 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3086 &Default::default(), &random_seed_bytes) {
3087 assert_eq!(err, "Cannot send a payment of 0 msat");
3088 } else { panic!(); }
3090 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3091 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3092 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3093 assert_eq!(route.paths[0].hops.len(), 2);
3095 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3096 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3097 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3098 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3099 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3100 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3102 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3103 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3104 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3105 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3106 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3107 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3111 fn invalid_first_hop_test() {
3112 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3113 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3114 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3115 let scorer = ln_test_utils::TestScorer::new();
3116 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3117 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3119 // Simple route to 2 via 1
3121 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3123 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3124 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3125 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3126 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3127 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3128 } else { panic!(); }
3130 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3131 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3132 assert_eq!(route.paths[0].hops.len(), 2);
3136 fn htlc_minimum_test() {
3137 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3138 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3139 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3140 let scorer = ln_test_utils::TestScorer::new();
3141 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3142 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3144 // Simple route to 2 via 1
3146 // Disable other paths
3147 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3148 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3149 short_channel_id: 12,
3151 flags: 2, // to disable
3152 cltv_expiry_delta: 0,
3153 htlc_minimum_msat: 0,
3154 htlc_maximum_msat: MAX_VALUE_MSAT,
3156 fee_proportional_millionths: 0,
3157 excess_data: Vec::new()
3159 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3160 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3161 short_channel_id: 3,
3163 flags: 2, // to disable
3164 cltv_expiry_delta: 0,
3165 htlc_minimum_msat: 0,
3166 htlc_maximum_msat: MAX_VALUE_MSAT,
3168 fee_proportional_millionths: 0,
3169 excess_data: Vec::new()
3171 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3172 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3173 short_channel_id: 13,
3175 flags: 2, // to disable
3176 cltv_expiry_delta: 0,
3177 htlc_minimum_msat: 0,
3178 htlc_maximum_msat: MAX_VALUE_MSAT,
3180 fee_proportional_millionths: 0,
3181 excess_data: Vec::new()
3183 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3184 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3185 short_channel_id: 6,
3187 flags: 2, // to disable
3188 cltv_expiry_delta: 0,
3189 htlc_minimum_msat: 0,
3190 htlc_maximum_msat: MAX_VALUE_MSAT,
3192 fee_proportional_millionths: 0,
3193 excess_data: Vec::new()
3195 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3196 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3197 short_channel_id: 7,
3199 flags: 2, // to disable
3200 cltv_expiry_delta: 0,
3201 htlc_minimum_msat: 0,
3202 htlc_maximum_msat: MAX_VALUE_MSAT,
3204 fee_proportional_millionths: 0,
3205 excess_data: Vec::new()
3208 // Check against amount_to_transfer_over_msat.
3209 // Set minimal HTLC of 200_000_000 msat.
3210 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3211 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3212 short_channel_id: 2,
3215 cltv_expiry_delta: 0,
3216 htlc_minimum_msat: 200_000_000,
3217 htlc_maximum_msat: MAX_VALUE_MSAT,
3219 fee_proportional_millionths: 0,
3220 excess_data: Vec::new()
3223 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3225 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3226 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3227 short_channel_id: 4,
3230 cltv_expiry_delta: 0,
3231 htlc_minimum_msat: 0,
3232 htlc_maximum_msat: 199_999_999,
3234 fee_proportional_millionths: 0,
3235 excess_data: Vec::new()
3238 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3239 let route_params = RouteParameters::from_payment_params_and_value(
3240 payment_params, 199_999_999);
3241 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3242 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3243 &Default::default(), &random_seed_bytes) {
3244 assert_eq!(err, "Failed to find a path to the given destination");
3245 } else { panic!(); }
3247 // Lift the restriction on the first hop.
3248 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3249 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3250 short_channel_id: 2,
3253 cltv_expiry_delta: 0,
3254 htlc_minimum_msat: 0,
3255 htlc_maximum_msat: MAX_VALUE_MSAT,
3257 fee_proportional_millionths: 0,
3258 excess_data: Vec::new()
3261 // A payment above the minimum should pass
3262 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3263 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3264 assert_eq!(route.paths[0].hops.len(), 2);
3268 fn htlc_minimum_overpay_test() {
3269 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3270 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3271 let config = UserConfig::default();
3272 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3273 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3275 let scorer = ln_test_utils::TestScorer::new();
3276 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3277 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3279 // A route to node#2 via two paths.
3280 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3281 // Thus, they can't send 60 without overpaying.
3282 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3283 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3284 short_channel_id: 2,
3287 cltv_expiry_delta: 0,
3288 htlc_minimum_msat: 35_000,
3289 htlc_maximum_msat: 40_000,
3291 fee_proportional_millionths: 0,
3292 excess_data: Vec::new()
3294 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3295 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3296 short_channel_id: 12,
3299 cltv_expiry_delta: 0,
3300 htlc_minimum_msat: 35_000,
3301 htlc_maximum_msat: 40_000,
3303 fee_proportional_millionths: 0,
3304 excess_data: Vec::new()
3308 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3309 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3310 short_channel_id: 13,
3313 cltv_expiry_delta: 0,
3314 htlc_minimum_msat: 0,
3315 htlc_maximum_msat: MAX_VALUE_MSAT,
3317 fee_proportional_millionths: 0,
3318 excess_data: Vec::new()
3320 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3321 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3322 short_channel_id: 4,
3325 cltv_expiry_delta: 0,
3326 htlc_minimum_msat: 0,
3327 htlc_maximum_msat: MAX_VALUE_MSAT,
3329 fee_proportional_millionths: 0,
3330 excess_data: Vec::new()
3333 // Disable other paths
3334 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3335 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3336 short_channel_id: 1,
3338 flags: 2, // to disable
3339 cltv_expiry_delta: 0,
3340 htlc_minimum_msat: 0,
3341 htlc_maximum_msat: MAX_VALUE_MSAT,
3343 fee_proportional_millionths: 0,
3344 excess_data: Vec::new()
3347 let mut route_params = RouteParameters::from_payment_params_and_value(
3348 payment_params.clone(), 60_000);
3349 route_params.max_total_routing_fee_msat = Some(15_000);
3350 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3351 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3352 // Overpay fees to hit htlc_minimum_msat.
3353 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3354 // TODO: this could be better balanced to overpay 10k and not 15k.
3355 assert_eq!(overpaid_fees, 15_000);
3357 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3358 // while taking even more fee to match htlc_minimum_msat.
3359 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3360 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3361 short_channel_id: 12,
3364 cltv_expiry_delta: 0,
3365 htlc_minimum_msat: 65_000,
3366 htlc_maximum_msat: 80_000,
3368 fee_proportional_millionths: 0,
3369 excess_data: Vec::new()
3371 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3372 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3373 short_channel_id: 2,
3376 cltv_expiry_delta: 0,
3377 htlc_minimum_msat: 0,
3378 htlc_maximum_msat: MAX_VALUE_MSAT,
3380 fee_proportional_millionths: 0,
3381 excess_data: Vec::new()
3383 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3384 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3385 short_channel_id: 4,
3388 cltv_expiry_delta: 0,
3389 htlc_minimum_msat: 0,
3390 htlc_maximum_msat: MAX_VALUE_MSAT,
3392 fee_proportional_millionths: 100_000,
3393 excess_data: Vec::new()
3396 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3397 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3398 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3399 assert_eq!(route.paths.len(), 1);
3400 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3401 let fees = route.paths[0].hops[0].fee_msat;
3402 assert_eq!(fees, 5_000);
3404 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3405 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3406 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3407 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3408 // the other channel.
3409 assert_eq!(route.paths.len(), 1);
3410 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3411 let fees = route.paths[0].hops[0].fee_msat;
3412 assert_eq!(fees, 5_000);
3416 fn htlc_minimum_recipient_overpay_test() {
3417 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3418 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3419 let config = UserConfig::default();
3420 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3421 let scorer = ln_test_utils::TestScorer::new();
3422 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3423 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3425 // Route to node2 over a single path which requires overpaying the recipient themselves.
3427 // First disable all paths except the us -> node1 -> node2 path
3428 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3429 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3430 short_channel_id: 13,
3433 cltv_expiry_delta: 0,
3434 htlc_minimum_msat: 0,
3435 htlc_maximum_msat: 0,
3437 fee_proportional_millionths: 0,
3438 excess_data: Vec::new()
3441 // Set channel 4 to free but with a high htlc_minimum_msat
3442 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3443 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3444 short_channel_id: 4,
3447 cltv_expiry_delta: 0,
3448 htlc_minimum_msat: 15_000,
3449 htlc_maximum_msat: MAX_VALUE_MSAT,
3451 fee_proportional_millionths: 0,
3452 excess_data: Vec::new()
3455 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3456 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3457 // what we try to find a route for, so this test only just happens to work out to exactly
3459 let mut route_params = RouteParameters::from_payment_params_and_value(
3460 payment_params.clone(), 5_000);
3461 route_params.max_total_routing_fee_msat = Some(9_999);
3462 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3463 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3464 &Default::default(), &random_seed_bytes) {
3465 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3466 } else { panic!(); }
3468 let mut route_params = RouteParameters::from_payment_params_and_value(
3469 payment_params.clone(), 5_000);
3470 route_params.max_total_routing_fee_msat = Some(10_000);
3471 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3472 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3473 assert_eq!(route.get_total_fees(), 10_000);
3477 fn disable_channels_test() {
3478 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3479 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3480 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3481 let scorer = ln_test_utils::TestScorer::new();
3482 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3483 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3485 // // Disable channels 4 and 12 by flags=2
3486 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3487 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3488 short_channel_id: 4,
3490 flags: 2, // to disable
3491 cltv_expiry_delta: 0,
3492 htlc_minimum_msat: 0,
3493 htlc_maximum_msat: MAX_VALUE_MSAT,
3495 fee_proportional_millionths: 0,
3496 excess_data: Vec::new()
3498 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3499 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3500 short_channel_id: 12,
3502 flags: 2, // to disable
3503 cltv_expiry_delta: 0,
3504 htlc_minimum_msat: 0,
3505 htlc_maximum_msat: MAX_VALUE_MSAT,
3507 fee_proportional_millionths: 0,
3508 excess_data: Vec::new()
3511 // If all the channels require some features we don't understand, route should fail
3512 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3513 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3514 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3515 &Default::default(), &random_seed_bytes) {
3516 assert_eq!(err, "Failed to find a path to the given destination");
3517 } else { panic!(); }
3519 // If we specify a channel to node7, that overrides our local channel view and that gets used
3520 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3521 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3522 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3523 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3524 &Default::default(), &random_seed_bytes).unwrap();
3525 assert_eq!(route.paths[0].hops.len(), 2);
3527 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3528 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3529 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3530 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3531 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3532 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3534 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3535 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3536 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3537 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3538 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3539 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3543 fn disable_node_test() {
3544 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3545 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3546 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3547 let scorer = ln_test_utils::TestScorer::new();
3548 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3549 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3551 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3552 let mut unknown_features = NodeFeatures::empty();
3553 unknown_features.set_unknown_feature_required();
3554 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3555 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3556 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3558 // If all nodes require some features we don't understand, route should fail
3559 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3560 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3561 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3562 &Default::default(), &random_seed_bytes) {
3563 assert_eq!(err, "Failed to find a path to the given destination");
3564 } else { panic!(); }
3566 // If we specify a channel to node7, that overrides our local channel view and that gets used
3567 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3568 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3569 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3570 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3571 &Default::default(), &random_seed_bytes).unwrap();
3572 assert_eq!(route.paths[0].hops.len(), 2);
3574 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3575 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3576 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3577 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3578 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3579 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3581 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3582 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3583 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3584 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3585 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3586 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3588 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3589 // naively) assume that the user checked the feature bits on the invoice, which override
3590 // the node_announcement.
3594 fn our_chans_test() {
3595 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3596 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3597 let scorer = ln_test_utils::TestScorer::new();
3598 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3599 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3601 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3602 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3603 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3604 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3605 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3606 assert_eq!(route.paths[0].hops.len(), 3);
3608 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3609 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3610 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3611 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3612 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3613 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3615 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3616 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3617 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3618 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3619 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3620 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3622 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3623 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3624 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3625 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3626 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3627 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3629 // If we specify a channel to node7, that overrides our local channel view and that gets used
3630 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3631 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3632 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3633 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3634 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3635 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3636 &Default::default(), &random_seed_bytes).unwrap();
3637 assert_eq!(route.paths[0].hops.len(), 2);
3639 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3640 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3641 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3642 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3643 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3644 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3646 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3647 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3648 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3649 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3650 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3651 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3654 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3655 let zero_fees = RoutingFees {
3657 proportional_millionths: 0,
3659 vec![RouteHint(vec![RouteHintHop {
3660 src_node_id: nodes[3],
3661 short_channel_id: 8,
3663 cltv_expiry_delta: (8 << 4) | 1,
3664 htlc_minimum_msat: None,
3665 htlc_maximum_msat: None,
3667 ]), RouteHint(vec![RouteHintHop {
3668 src_node_id: nodes[4],
3669 short_channel_id: 9,
3672 proportional_millionths: 0,
3674 cltv_expiry_delta: (9 << 4) | 1,
3675 htlc_minimum_msat: None,
3676 htlc_maximum_msat: None,
3677 }]), RouteHint(vec![RouteHintHop {
3678 src_node_id: nodes[5],
3679 short_channel_id: 10,
3681 cltv_expiry_delta: (10 << 4) | 1,
3682 htlc_minimum_msat: None,
3683 htlc_maximum_msat: None,
3687 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3688 let zero_fees = RoutingFees {
3690 proportional_millionths: 0,
3692 vec![RouteHint(vec![RouteHintHop {
3693 src_node_id: nodes[2],
3694 short_channel_id: 5,
3697 proportional_millionths: 0,
3699 cltv_expiry_delta: (5 << 4) | 1,
3700 htlc_minimum_msat: None,
3701 htlc_maximum_msat: None,
3703 src_node_id: nodes[3],
3704 short_channel_id: 8,
3706 cltv_expiry_delta: (8 << 4) | 1,
3707 htlc_minimum_msat: None,
3708 htlc_maximum_msat: None,
3710 ]), RouteHint(vec![RouteHintHop {
3711 src_node_id: nodes[4],
3712 short_channel_id: 9,
3715 proportional_millionths: 0,
3717 cltv_expiry_delta: (9 << 4) | 1,
3718 htlc_minimum_msat: None,
3719 htlc_maximum_msat: None,
3720 }]), RouteHint(vec![RouteHintHop {
3721 src_node_id: nodes[5],
3722 short_channel_id: 10,
3724 cltv_expiry_delta: (10 << 4) | 1,
3725 htlc_minimum_msat: None,
3726 htlc_maximum_msat: None,
3731 fn partial_route_hint_test() {
3732 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3733 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3734 let scorer = ln_test_utils::TestScorer::new();
3735 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3736 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3738 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3739 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3740 // RouteHint may be partially used by the algo to build the best path.
3742 // First check that last hop can't have its source as the payee.
3743 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3744 src_node_id: nodes[6],
3745 short_channel_id: 8,
3748 proportional_millionths: 0,
3750 cltv_expiry_delta: (8 << 4) | 1,
3751 htlc_minimum_msat: None,
3752 htlc_maximum_msat: None,
3755 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3756 invalid_last_hops.push(invalid_last_hop);
3758 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3759 .with_route_hints(invalid_last_hops).unwrap();
3760 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3761 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3762 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3763 &Default::default(), &random_seed_bytes) {
3764 assert_eq!(err, "Route hint cannot have the payee as the source.");
3765 } else { panic!(); }
3768 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3769 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3770 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3771 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3772 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3773 assert_eq!(route.paths[0].hops.len(), 5);
3775 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3776 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3777 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3778 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3779 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3780 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3782 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3783 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3784 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3785 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3786 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3787 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3789 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3790 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3791 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3792 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3793 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3794 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3796 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3797 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3798 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3799 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3800 // If we have a peer in the node map, we'll use their features here since we don't have
3801 // a way of figuring out their features from the invoice:
3802 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3803 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3805 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3806 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3807 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3808 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3809 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3810 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3813 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3814 let zero_fees = RoutingFees {
3816 proportional_millionths: 0,
3818 vec![RouteHint(vec![RouteHintHop {
3819 src_node_id: nodes[3],
3820 short_channel_id: 8,
3822 cltv_expiry_delta: (8 << 4) | 1,
3823 htlc_minimum_msat: None,
3824 htlc_maximum_msat: None,
3825 }]), RouteHint(vec![
3827 ]), RouteHint(vec![RouteHintHop {
3828 src_node_id: nodes[5],
3829 short_channel_id: 10,
3831 cltv_expiry_delta: (10 << 4) | 1,
3832 htlc_minimum_msat: None,
3833 htlc_maximum_msat: None,
3838 fn ignores_empty_last_hops_test() {
3839 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3840 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3841 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3842 let scorer = ln_test_utils::TestScorer::new();
3843 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3844 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3846 // Test handling of an empty RouteHint passed in Invoice.
3847 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3848 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3849 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3850 assert_eq!(route.paths[0].hops.len(), 5);
3852 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3853 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3854 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3855 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3856 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3857 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3859 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3860 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3861 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3862 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3863 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3864 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3866 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3867 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3868 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3869 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3870 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3871 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3873 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3874 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3875 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3876 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3877 // If we have a peer in the node map, we'll use their features here since we don't have
3878 // a way of figuring out their features from the invoice:
3879 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3880 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3882 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3883 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3884 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3885 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3886 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3887 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3890 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3892 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3893 let zero_fees = RoutingFees {
3895 proportional_millionths: 0,
3897 vec![RouteHint(vec![RouteHintHop {
3898 src_node_id: hint_hops[0],
3899 short_channel_id: 0xff00,
3902 proportional_millionths: 0,
3904 cltv_expiry_delta: (5 << 4) | 1,
3905 htlc_minimum_msat: None,
3906 htlc_maximum_msat: None,
3908 src_node_id: hint_hops[1],
3909 short_channel_id: 0xff01,
3911 cltv_expiry_delta: (8 << 4) | 1,
3912 htlc_minimum_msat: None,
3913 htlc_maximum_msat: None,
3918 fn multi_hint_last_hops_test() {
3919 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3920 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3921 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3922 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3923 let scorer = ln_test_utils::TestScorer::new();
3924 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3925 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3926 // Test through channels 2, 3, 0xff00, 0xff01.
3927 // Test shows that multiple hop hints are considered.
3929 // Disabling channels 6 & 7 by flags=2
3930 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3931 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3932 short_channel_id: 6,
3934 flags: 2, // to disable
3935 cltv_expiry_delta: 0,
3936 htlc_minimum_msat: 0,
3937 htlc_maximum_msat: MAX_VALUE_MSAT,
3939 fee_proportional_millionths: 0,
3940 excess_data: Vec::new()
3942 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3943 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3944 short_channel_id: 7,
3946 flags: 2, // to disable
3947 cltv_expiry_delta: 0,
3948 htlc_minimum_msat: 0,
3949 htlc_maximum_msat: MAX_VALUE_MSAT,
3951 fee_proportional_millionths: 0,
3952 excess_data: Vec::new()
3955 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3956 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3957 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3958 assert_eq!(route.paths[0].hops.len(), 4);
3960 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3961 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3962 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3963 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3964 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3965 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3967 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3968 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3969 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3970 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3971 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3972 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3974 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3975 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3976 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3977 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3978 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3979 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3981 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3982 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3983 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3984 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3985 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3986 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3990 fn private_multi_hint_last_hops_test() {
3991 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3992 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3994 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3995 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3997 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3998 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3999 let scorer = ln_test_utils::TestScorer::new();
4000 // Test through channels 2, 3, 0xff00, 0xff01.
4001 // Test shows that multiple hop hints are considered.
4003 // Disabling channels 6 & 7 by flags=2
4004 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4005 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4006 short_channel_id: 6,
4008 flags: 2, // to disable
4009 cltv_expiry_delta: 0,
4010 htlc_minimum_msat: 0,
4011 htlc_maximum_msat: MAX_VALUE_MSAT,
4013 fee_proportional_millionths: 0,
4014 excess_data: Vec::new()
4016 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4017 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4018 short_channel_id: 7,
4020 flags: 2, // to disable
4021 cltv_expiry_delta: 0,
4022 htlc_minimum_msat: 0,
4023 htlc_maximum_msat: MAX_VALUE_MSAT,
4025 fee_proportional_millionths: 0,
4026 excess_data: Vec::new()
4029 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4030 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4031 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4032 assert_eq!(route.paths[0].hops.len(), 4);
4034 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4035 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4036 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4037 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4038 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4039 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4041 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4042 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4043 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4044 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4045 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4046 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4048 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4049 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4050 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4051 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4052 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4053 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4055 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4056 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4057 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4058 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4059 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4060 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4063 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4064 let zero_fees = RoutingFees {
4066 proportional_millionths: 0,
4068 vec![RouteHint(vec![RouteHintHop {
4069 src_node_id: nodes[4],
4070 short_channel_id: 11,
4072 cltv_expiry_delta: (11 << 4) | 1,
4073 htlc_minimum_msat: None,
4074 htlc_maximum_msat: None,
4076 src_node_id: nodes[3],
4077 short_channel_id: 8,
4079 cltv_expiry_delta: (8 << 4) | 1,
4080 htlc_minimum_msat: None,
4081 htlc_maximum_msat: None,
4082 }]), RouteHint(vec![RouteHintHop {
4083 src_node_id: nodes[4],
4084 short_channel_id: 9,
4087 proportional_millionths: 0,
4089 cltv_expiry_delta: (9 << 4) | 1,
4090 htlc_minimum_msat: None,
4091 htlc_maximum_msat: None,
4092 }]), RouteHint(vec![RouteHintHop {
4093 src_node_id: nodes[5],
4094 short_channel_id: 10,
4096 cltv_expiry_delta: (10 << 4) | 1,
4097 htlc_minimum_msat: None,
4098 htlc_maximum_msat: None,
4103 fn last_hops_with_public_channel_test() {
4104 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4105 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4106 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4107 let scorer = ln_test_utils::TestScorer::new();
4108 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4109 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4110 // This test shows that public routes can be present in the invoice
4111 // which would be handled in the same manner.
4113 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4114 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4115 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4116 assert_eq!(route.paths[0].hops.len(), 5);
4118 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4119 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4120 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4121 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4122 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4123 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4125 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4126 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4127 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4128 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4129 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4130 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4132 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4133 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4134 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4135 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4136 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4137 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4139 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4140 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4141 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4142 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4143 // If we have a peer in the node map, we'll use their features here since we don't have
4144 // a way of figuring out their features from the invoice:
4145 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4146 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4148 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4149 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4150 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4151 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4152 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4153 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4157 fn our_chans_last_hop_connect_test() {
4158 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4159 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4160 let scorer = ln_test_utils::TestScorer::new();
4161 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4162 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4164 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4165 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4166 let mut last_hops = last_hops(&nodes);
4167 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4168 .with_route_hints(last_hops.clone()).unwrap();
4169 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4170 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4171 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4172 &Default::default(), &random_seed_bytes).unwrap();
4173 assert_eq!(route.paths[0].hops.len(), 2);
4175 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4176 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4177 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4178 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4179 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4180 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4182 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4183 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4184 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4185 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4186 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4187 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4189 last_hops[0].0[0].fees.base_msat = 1000;
4191 // Revert to via 6 as the fee on 8 goes up
4192 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4193 .with_route_hints(last_hops).unwrap();
4194 let route_params = RouteParameters::from_payment_params_and_value(
4195 payment_params.clone(), 100);
4196 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4197 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4198 assert_eq!(route.paths[0].hops.len(), 4);
4200 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4201 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4202 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4203 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4204 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4205 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4207 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4208 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4209 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4210 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4211 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4212 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4214 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4215 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4216 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4217 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4218 // If we have a peer in the node map, we'll use their features here since we don't have
4219 // a way of figuring out their features from the invoice:
4220 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4221 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4223 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4224 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4225 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4226 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4227 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4228 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4230 // ...but still use 8 for larger payments as 6 has a variable feerate
4231 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4232 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4233 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4234 assert_eq!(route.paths[0].hops.len(), 5);
4236 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4237 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4238 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4239 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4240 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4241 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4243 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4244 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4245 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4246 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4247 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4248 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4250 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4251 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4252 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4253 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4254 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4255 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4257 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4258 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4259 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4260 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4261 // If we have a peer in the node map, we'll use their features here since we don't have
4262 // a way of figuring out their features from the invoice:
4263 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4264 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4266 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4267 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4268 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4269 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4270 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4271 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4274 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> {
4275 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4276 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4277 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4279 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4280 let last_hops = RouteHint(vec![RouteHintHop {
4281 src_node_id: middle_node_id,
4282 short_channel_id: 8,
4285 proportional_millionths: last_hop_fee_prop,
4287 cltv_expiry_delta: (8 << 4) | 1,
4288 htlc_minimum_msat: None,
4289 htlc_maximum_msat: last_hop_htlc_max,
4291 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4292 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4293 let scorer = ln_test_utils::TestScorer::new();
4294 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4295 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4296 let logger = ln_test_utils::TestLogger::new();
4297 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4298 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4299 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4300 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4301 &random_seed_bytes);
4306 fn unannounced_path_test() {
4307 // We should be able to send a payment to a destination without any help of a routing graph
4308 // if we have a channel with a common counterparty that appears in the first and last hop
4310 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4312 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4313 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4314 assert_eq!(route.paths[0].hops.len(), 2);
4316 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4317 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4318 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4319 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4320 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4321 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4323 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4324 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4325 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4326 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4327 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4328 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4332 fn overflow_unannounced_path_test_liquidity_underflow() {
4333 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4334 // the last-hop had a fee which overflowed a u64, we'd panic.
4335 // This was due to us adding the first-hop from us unconditionally, causing us to think
4336 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4337 // In this test, we previously hit a subtraction underflow due to having less available
4338 // liquidity at the last hop than 0.
4339 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());
4343 fn overflow_unannounced_path_test_feerate_overflow() {
4344 // This tests for the same case as above, except instead of hitting a subtraction
4345 // underflow, we hit a case where the fee charged at a hop overflowed.
4346 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());
4350 fn available_amount_while_routing_test() {
4351 // Tests whether we choose the correct available channel amount while routing.
4353 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4354 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4355 let scorer = ln_test_utils::TestScorer::new();
4356 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4357 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4358 let config = UserConfig::default();
4359 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4360 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4363 // We will use a simple single-path route from
4364 // our node to node2 via node0: channels {1, 3}.
4366 // First disable all other paths.
4367 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4368 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4369 short_channel_id: 2,
4372 cltv_expiry_delta: 0,
4373 htlc_minimum_msat: 0,
4374 htlc_maximum_msat: 100_000,
4376 fee_proportional_millionths: 0,
4377 excess_data: Vec::new()
4379 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4380 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4381 short_channel_id: 12,
4384 cltv_expiry_delta: 0,
4385 htlc_minimum_msat: 0,
4386 htlc_maximum_msat: 100_000,
4388 fee_proportional_millionths: 0,
4389 excess_data: Vec::new()
4392 // Make the first channel (#1) very permissive,
4393 // and we will be testing all limits on the second channel.
4394 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4395 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4396 short_channel_id: 1,
4399 cltv_expiry_delta: 0,
4400 htlc_minimum_msat: 0,
4401 htlc_maximum_msat: 1_000_000_000,
4403 fee_proportional_millionths: 0,
4404 excess_data: Vec::new()
4407 // First, let's see if routing works if we have absolutely no idea about the available amount.
4408 // In this case, it should be set to 250_000 sats.
4409 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4410 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4411 short_channel_id: 3,
4414 cltv_expiry_delta: 0,
4415 htlc_minimum_msat: 0,
4416 htlc_maximum_msat: 250_000_000,
4418 fee_proportional_millionths: 0,
4419 excess_data: Vec::new()
4423 // Attempt to route more than available results in a failure.
4424 let route_params = RouteParameters::from_payment_params_and_value(
4425 payment_params.clone(), 250_000_001);
4426 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4427 &our_id, &route_params, &network_graph.read_only(), None,
4428 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4429 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4430 } else { panic!(); }
4434 // Now, attempt to route an exact amount we have should be fine.
4435 let route_params = RouteParameters::from_payment_params_and_value(
4436 payment_params.clone(), 250_000_000);
4437 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4438 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4439 assert_eq!(route.paths.len(), 1);
4440 let path = route.paths.last().unwrap();
4441 assert_eq!(path.hops.len(), 2);
4442 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4443 assert_eq!(path.final_value_msat(), 250_000_000);
4446 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4447 // Disable channel #1 and use another first hop.
4448 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4449 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4450 short_channel_id: 1,
4453 cltv_expiry_delta: 0,
4454 htlc_minimum_msat: 0,
4455 htlc_maximum_msat: 1_000_000_000,
4457 fee_proportional_millionths: 0,
4458 excess_data: Vec::new()
4461 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4462 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4465 // Attempt to route more than available results in a failure.
4466 let route_params = RouteParameters::from_payment_params_and_value(
4467 payment_params.clone(), 200_000_001);
4468 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4469 &our_id, &route_params, &network_graph.read_only(),
4470 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4471 &Default::default(), &random_seed_bytes) {
4472 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4473 } else { panic!(); }
4477 // Now, attempt to route an exact amount we have should be fine.
4478 let route_params = RouteParameters::from_payment_params_and_value(
4479 payment_params.clone(), 200_000_000);
4480 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4481 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4482 &Default::default(), &random_seed_bytes).unwrap();
4483 assert_eq!(route.paths.len(), 1);
4484 let path = route.paths.last().unwrap();
4485 assert_eq!(path.hops.len(), 2);
4486 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4487 assert_eq!(path.final_value_msat(), 200_000_000);
4490 // Enable channel #1 back.
4491 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4492 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4493 short_channel_id: 1,
4496 cltv_expiry_delta: 0,
4497 htlc_minimum_msat: 0,
4498 htlc_maximum_msat: 1_000_000_000,
4500 fee_proportional_millionths: 0,
4501 excess_data: Vec::new()
4505 // Now let's see if routing works if we know only htlc_maximum_msat.
4506 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4507 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4508 short_channel_id: 3,
4511 cltv_expiry_delta: 0,
4512 htlc_minimum_msat: 0,
4513 htlc_maximum_msat: 15_000,
4515 fee_proportional_millionths: 0,
4516 excess_data: Vec::new()
4520 // Attempt to route more than available results in a failure.
4521 let route_params = RouteParameters::from_payment_params_and_value(
4522 payment_params.clone(), 15_001);
4523 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4524 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4525 &scorer, &Default::default(), &random_seed_bytes) {
4526 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4527 } else { panic!(); }
4531 // Now, attempt to route an exact amount we have should be fine.
4532 let route_params = RouteParameters::from_payment_params_and_value(
4533 payment_params.clone(), 15_000);
4534 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4535 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4536 assert_eq!(route.paths.len(), 1);
4537 let path = route.paths.last().unwrap();
4538 assert_eq!(path.hops.len(), 2);
4539 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4540 assert_eq!(path.final_value_msat(), 15_000);
4543 // Now let's see if routing works if we know only capacity from the UTXO.
4545 // We can't change UTXO capacity on the fly, so we'll disable
4546 // the existing channel and add another one with the capacity we need.
4547 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4548 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4549 short_channel_id: 3,
4552 cltv_expiry_delta: 0,
4553 htlc_minimum_msat: 0,
4554 htlc_maximum_msat: MAX_VALUE_MSAT,
4556 fee_proportional_millionths: 0,
4557 excess_data: Vec::new()
4560 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4561 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4562 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4563 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4564 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4566 *chain_monitor.utxo_ret.lock().unwrap() =
4567 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4568 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4570 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4571 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4572 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4573 short_channel_id: 333,
4576 cltv_expiry_delta: (3 << 4) | 1,
4577 htlc_minimum_msat: 0,
4578 htlc_maximum_msat: 15_000,
4580 fee_proportional_millionths: 0,
4581 excess_data: Vec::new()
4583 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4584 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4585 short_channel_id: 333,
4588 cltv_expiry_delta: (3 << 4) | 2,
4589 htlc_minimum_msat: 0,
4590 htlc_maximum_msat: 15_000,
4592 fee_proportional_millionths: 0,
4593 excess_data: Vec::new()
4597 // Attempt to route more than available results in a failure.
4598 let route_params = RouteParameters::from_payment_params_and_value(
4599 payment_params.clone(), 15_001);
4600 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4601 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4602 &scorer, &Default::default(), &random_seed_bytes) {
4603 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4604 } else { panic!(); }
4608 // Now, attempt to route an exact amount we have should be fine.
4609 let route_params = RouteParameters::from_payment_params_and_value(
4610 payment_params.clone(), 15_000);
4611 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4612 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4613 assert_eq!(route.paths.len(), 1);
4614 let path = route.paths.last().unwrap();
4615 assert_eq!(path.hops.len(), 2);
4616 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4617 assert_eq!(path.final_value_msat(), 15_000);
4620 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4621 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4622 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4623 short_channel_id: 333,
4626 cltv_expiry_delta: 0,
4627 htlc_minimum_msat: 0,
4628 htlc_maximum_msat: 10_000,
4630 fee_proportional_millionths: 0,
4631 excess_data: Vec::new()
4635 // Attempt to route more than available results in a failure.
4636 let route_params = RouteParameters::from_payment_params_and_value(
4637 payment_params.clone(), 10_001);
4638 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4639 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4640 &scorer, &Default::default(), &random_seed_bytes) {
4641 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4642 } else { panic!(); }
4646 // Now, attempt to route an exact amount we have should be fine.
4647 let route_params = RouteParameters::from_payment_params_and_value(
4648 payment_params.clone(), 10_000);
4649 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4650 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4651 assert_eq!(route.paths.len(), 1);
4652 let path = route.paths.last().unwrap();
4653 assert_eq!(path.hops.len(), 2);
4654 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4655 assert_eq!(path.final_value_msat(), 10_000);
4660 fn available_liquidity_last_hop_test() {
4661 // Check that available liquidity properly limits the path even when only
4662 // one of the latter hops is limited.
4663 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4664 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4665 let scorer = ln_test_utils::TestScorer::new();
4666 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4667 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4668 let config = UserConfig::default();
4669 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4670 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4673 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4674 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4675 // Total capacity: 50 sats.
4677 // Disable other potential paths.
4678 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4679 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4680 short_channel_id: 2,
4683 cltv_expiry_delta: 0,
4684 htlc_minimum_msat: 0,
4685 htlc_maximum_msat: 100_000,
4687 fee_proportional_millionths: 0,
4688 excess_data: Vec::new()
4690 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4691 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4692 short_channel_id: 7,
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()
4705 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4706 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4707 short_channel_id: 12,
4710 cltv_expiry_delta: 0,
4711 htlc_minimum_msat: 0,
4712 htlc_maximum_msat: 100_000,
4714 fee_proportional_millionths: 0,
4715 excess_data: Vec::new()
4717 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4718 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4719 short_channel_id: 13,
4722 cltv_expiry_delta: 0,
4723 htlc_minimum_msat: 0,
4724 htlc_maximum_msat: 100_000,
4726 fee_proportional_millionths: 0,
4727 excess_data: Vec::new()
4730 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4731 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4732 short_channel_id: 6,
4735 cltv_expiry_delta: 0,
4736 htlc_minimum_msat: 0,
4737 htlc_maximum_msat: 50_000,
4739 fee_proportional_millionths: 0,
4740 excess_data: Vec::new()
4742 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4743 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4744 short_channel_id: 11,
4747 cltv_expiry_delta: 0,
4748 htlc_minimum_msat: 0,
4749 htlc_maximum_msat: 100_000,
4751 fee_proportional_millionths: 0,
4752 excess_data: Vec::new()
4755 // Attempt to route more than available results in a failure.
4756 let route_params = RouteParameters::from_payment_params_and_value(
4757 payment_params.clone(), 60_000);
4758 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4759 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4760 &scorer, &Default::default(), &random_seed_bytes) {
4761 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4762 } else { panic!(); }
4766 // Now, attempt to route 49 sats (just a bit below the capacity).
4767 let route_params = RouteParameters::from_payment_params_and_value(
4768 payment_params.clone(), 49_000);
4769 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4770 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4771 assert_eq!(route.paths.len(), 1);
4772 let mut total_amount_paid_msat = 0;
4773 for path in &route.paths {
4774 assert_eq!(path.hops.len(), 4);
4775 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4776 total_amount_paid_msat += path.final_value_msat();
4778 assert_eq!(total_amount_paid_msat, 49_000);
4782 // Attempt to route an exact amount is also fine
4783 let route_params = RouteParameters::from_payment_params_and_value(
4784 payment_params, 50_000);
4785 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4786 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4787 assert_eq!(route.paths.len(), 1);
4788 let mut total_amount_paid_msat = 0;
4789 for path in &route.paths {
4790 assert_eq!(path.hops.len(), 4);
4791 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4792 total_amount_paid_msat += path.final_value_msat();
4794 assert_eq!(total_amount_paid_msat, 50_000);
4799 fn ignore_fee_first_hop_test() {
4800 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4801 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4802 let scorer = ln_test_utils::TestScorer::new();
4803 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4804 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4805 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4807 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4808 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4809 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4810 short_channel_id: 1,
4813 cltv_expiry_delta: 0,
4814 htlc_minimum_msat: 0,
4815 htlc_maximum_msat: 100_000,
4816 fee_base_msat: 1_000_000,
4817 fee_proportional_millionths: 0,
4818 excess_data: Vec::new()
4820 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4821 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4822 short_channel_id: 3,
4825 cltv_expiry_delta: 0,
4826 htlc_minimum_msat: 0,
4827 htlc_maximum_msat: 50_000,
4829 fee_proportional_millionths: 0,
4830 excess_data: Vec::new()
4834 let route_params = RouteParameters::from_payment_params_and_value(
4835 payment_params, 50_000);
4836 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4837 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4838 assert_eq!(route.paths.len(), 1);
4839 let mut total_amount_paid_msat = 0;
4840 for path in &route.paths {
4841 assert_eq!(path.hops.len(), 2);
4842 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4843 total_amount_paid_msat += path.final_value_msat();
4845 assert_eq!(total_amount_paid_msat, 50_000);
4850 fn simple_mpp_route_test() {
4851 let (secp_ctx, _, _, _, _) = build_graph();
4852 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4853 let config = UserConfig::default();
4854 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4855 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4857 do_simple_mpp_route_test(clear_payment_params);
4859 // MPP to a 1-hop blinded path for nodes[2]
4860 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
4861 let blinded_path = BlindedPath {
4862 introduction_node_id: nodes[2],
4863 blinding_point: ln_test_utils::pubkey(42),
4864 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4866 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4868 fee_proportional_millionths: 0,
4869 htlc_minimum_msat: 0,
4870 htlc_maximum_msat: 0,
4871 cltv_expiry_delta: 0,
4872 features: BlindedHopFeatures::empty(),
4874 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4875 .with_bolt12_features(bolt12_features.clone()).unwrap();
4876 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4878 // MPP to 3 2-hop blinded paths
4879 let mut blinded_path_node_0 = blinded_path.clone();
4880 blinded_path_node_0.introduction_node_id = nodes[0];
4881 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4882 let mut node_0_payinfo = blinded_payinfo.clone();
4883 node_0_payinfo.htlc_maximum_msat = 50_000;
4885 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4886 blinded_path_node_7.introduction_node_id = nodes[7];
4887 let mut node_7_payinfo = blinded_payinfo.clone();
4888 node_7_payinfo.htlc_maximum_msat = 60_000;
4890 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4891 blinded_path_node_1.introduction_node_id = nodes[1];
4892 let mut node_1_payinfo = blinded_payinfo.clone();
4893 node_1_payinfo.htlc_maximum_msat = 180_000;
4895 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4897 (node_0_payinfo, blinded_path_node_0),
4898 (node_7_payinfo, blinded_path_node_7),
4899 (node_1_payinfo, blinded_path_node_1)
4901 .with_bolt12_features(bolt12_features).unwrap();
4902 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4906 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4907 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4908 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4909 let scorer = ln_test_utils::TestScorer::new();
4910 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4911 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4913 // We need a route consisting of 3 paths:
4914 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4915 // To achieve this, the amount being transferred should be around
4916 // the total capacity of these 3 paths.
4918 // First, we set limits on these (previously unlimited) channels.
4919 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4921 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4922 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4923 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4924 short_channel_id: 1,
4927 cltv_expiry_delta: 0,
4928 htlc_minimum_msat: 0,
4929 htlc_maximum_msat: 100_000,
4931 fee_proportional_millionths: 0,
4932 excess_data: Vec::new()
4934 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4935 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4936 short_channel_id: 3,
4939 cltv_expiry_delta: 0,
4940 htlc_minimum_msat: 0,
4941 htlc_maximum_msat: 50_000,
4943 fee_proportional_millionths: 0,
4944 excess_data: Vec::new()
4947 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4948 // (total limit 60).
4949 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4950 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4951 short_channel_id: 12,
4954 cltv_expiry_delta: 0,
4955 htlc_minimum_msat: 0,
4956 htlc_maximum_msat: 60_000,
4958 fee_proportional_millionths: 0,
4959 excess_data: Vec::new()
4961 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4962 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4963 short_channel_id: 13,
4966 cltv_expiry_delta: 0,
4967 htlc_minimum_msat: 0,
4968 htlc_maximum_msat: 60_000,
4970 fee_proportional_millionths: 0,
4971 excess_data: Vec::new()
4974 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4975 // (total capacity 180 sats).
4976 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4977 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4978 short_channel_id: 2,
4981 cltv_expiry_delta: 0,
4982 htlc_minimum_msat: 0,
4983 htlc_maximum_msat: 200_000,
4985 fee_proportional_millionths: 0,
4986 excess_data: Vec::new()
4988 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4989 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4990 short_channel_id: 4,
4993 cltv_expiry_delta: 0,
4994 htlc_minimum_msat: 0,
4995 htlc_maximum_msat: 180_000,
4997 fee_proportional_millionths: 0,
4998 excess_data: Vec::new()
5002 // Attempt to route more than available results in a failure.
5003 let route_params = RouteParameters::from_payment_params_and_value(
5004 payment_params.clone(), 300_000);
5005 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5006 &our_id, &route_params, &network_graph.read_only(), None,
5007 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5008 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5009 } else { panic!(); }
5013 // Attempt to route while setting max_path_count to 0 results in a failure.
5014 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5015 let route_params = RouteParameters::from_payment_params_and_value(
5016 zero_payment_params, 100);
5017 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5018 &our_id, &route_params, &network_graph.read_only(), None,
5019 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5020 assert_eq!(err, "Can't find a route with no paths allowed.");
5021 } else { panic!(); }
5025 // Attempt to route while setting max_path_count to 3 results in a failure.
5026 // This is the case because the minimal_value_contribution_msat would require each path
5027 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5028 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5029 let route_params = RouteParameters::from_payment_params_and_value(
5030 fail_payment_params, 250_000);
5031 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5032 &our_id, &route_params, &network_graph.read_only(), None,
5033 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5034 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5035 } else { panic!(); }
5039 // Now, attempt to route 250 sats (just a bit below the capacity).
5040 // Our algorithm should provide us with these 3 paths.
5041 let route_params = RouteParameters::from_payment_params_and_value(
5042 payment_params.clone(), 250_000);
5043 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5044 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5045 assert_eq!(route.paths.len(), 3);
5046 let mut total_amount_paid_msat = 0;
5047 for path in &route.paths {
5048 if let Some(bt) = &path.blinded_tail {
5049 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5051 assert_eq!(path.hops.len(), 2);
5052 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5054 total_amount_paid_msat += path.final_value_msat();
5056 assert_eq!(total_amount_paid_msat, 250_000);
5060 // Attempt to route an exact amount is also fine
5061 let route_params = RouteParameters::from_payment_params_and_value(
5062 payment_params.clone(), 290_000);
5063 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5064 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5065 assert_eq!(route.paths.len(), 3);
5066 let mut total_amount_paid_msat = 0;
5067 for path in &route.paths {
5068 if payment_params.payee.blinded_route_hints().len() != 0 {
5069 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5070 if let Some(bt) = &path.blinded_tail {
5071 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5072 if bt.hops.len() > 1 {
5073 assert_eq!(path.hops.last().unwrap().pubkey,
5074 payment_params.payee.blinded_route_hints().iter()
5075 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5076 .map(|(_, p)| p.introduction_node_id).unwrap());
5078 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5081 assert_eq!(path.hops.len(), 2);
5082 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5084 total_amount_paid_msat += path.final_value_msat();
5086 assert_eq!(total_amount_paid_msat, 290_000);
5091 fn long_mpp_route_test() {
5092 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5093 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5094 let scorer = ln_test_utils::TestScorer::new();
5095 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5096 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5097 let config = UserConfig::default();
5098 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5099 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5102 // We need a route consisting of 3 paths:
5103 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5104 // Note that these paths overlap (channels 5, 12, 13).
5105 // We will route 300 sats.
5106 // Each path will have 100 sats capacity, those channels which
5107 // are used twice will have 200 sats capacity.
5109 // Disable other potential paths.
5110 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5111 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5112 short_channel_id: 2,
5115 cltv_expiry_delta: 0,
5116 htlc_minimum_msat: 0,
5117 htlc_maximum_msat: 100_000,
5119 fee_proportional_millionths: 0,
5120 excess_data: Vec::new()
5122 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5123 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5124 short_channel_id: 7,
5127 cltv_expiry_delta: 0,
5128 htlc_minimum_msat: 0,
5129 htlc_maximum_msat: 100_000,
5131 fee_proportional_millionths: 0,
5132 excess_data: Vec::new()
5135 // Path via {node0, node2} is channels {1, 3, 5}.
5136 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5137 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5138 short_channel_id: 1,
5141 cltv_expiry_delta: 0,
5142 htlc_minimum_msat: 0,
5143 htlc_maximum_msat: 100_000,
5145 fee_proportional_millionths: 0,
5146 excess_data: Vec::new()
5148 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5149 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5150 short_channel_id: 3,
5153 cltv_expiry_delta: 0,
5154 htlc_minimum_msat: 0,
5155 htlc_maximum_msat: 100_000,
5157 fee_proportional_millionths: 0,
5158 excess_data: Vec::new()
5161 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5162 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5163 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5164 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5165 short_channel_id: 5,
5168 cltv_expiry_delta: 0,
5169 htlc_minimum_msat: 0,
5170 htlc_maximum_msat: 200_000,
5172 fee_proportional_millionths: 0,
5173 excess_data: Vec::new()
5176 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5177 // Add 100 sats to the capacities of {12, 13}, because these channels
5178 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5179 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5180 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5181 short_channel_id: 12,
5184 cltv_expiry_delta: 0,
5185 htlc_minimum_msat: 0,
5186 htlc_maximum_msat: 200_000,
5188 fee_proportional_millionths: 0,
5189 excess_data: Vec::new()
5191 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5192 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5193 short_channel_id: 13,
5196 cltv_expiry_delta: 0,
5197 htlc_minimum_msat: 0,
5198 htlc_maximum_msat: 200_000,
5200 fee_proportional_millionths: 0,
5201 excess_data: Vec::new()
5204 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5205 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5206 short_channel_id: 6,
5209 cltv_expiry_delta: 0,
5210 htlc_minimum_msat: 0,
5211 htlc_maximum_msat: 100_000,
5213 fee_proportional_millionths: 0,
5214 excess_data: Vec::new()
5216 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5217 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5218 short_channel_id: 11,
5221 cltv_expiry_delta: 0,
5222 htlc_minimum_msat: 0,
5223 htlc_maximum_msat: 100_000,
5225 fee_proportional_millionths: 0,
5226 excess_data: Vec::new()
5229 // Path via {node7, node2} is channels {12, 13, 5}.
5230 // We already limited them to 200 sats (they are used twice for 100 sats).
5231 // Nothing to do here.
5234 // Attempt to route more than available results in a failure.
5235 let route_params = RouteParameters::from_payment_params_and_value(
5236 payment_params.clone(), 350_000);
5237 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5238 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5239 &scorer, &Default::default(), &random_seed_bytes) {
5240 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5241 } else { panic!(); }
5245 // Now, attempt to route 300 sats (exact amount we can route).
5246 // Our algorithm should provide us with these 3 paths, 100 sats each.
5247 let route_params = RouteParameters::from_payment_params_and_value(
5248 payment_params, 300_000);
5249 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5250 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5251 assert_eq!(route.paths.len(), 3);
5253 let mut total_amount_paid_msat = 0;
5254 for path in &route.paths {
5255 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5256 total_amount_paid_msat += path.final_value_msat();
5258 assert_eq!(total_amount_paid_msat, 300_000);
5264 fn mpp_cheaper_route_test() {
5265 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5266 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5267 let scorer = ln_test_utils::TestScorer::new();
5268 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5269 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5270 let config = UserConfig::default();
5271 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5272 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5275 // This test checks that if we have two cheaper paths and one more expensive path,
5276 // so that liquidity-wise any 2 of 3 combination is sufficient,
5277 // two cheaper paths will be taken.
5278 // These paths have equal available liquidity.
5280 // We need a combination of 3 paths:
5281 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5282 // Note that these paths overlap (channels 5, 12, 13).
5283 // Each path will have 100 sats capacity, those channels which
5284 // are used twice will have 200 sats capacity.
5286 // Disable other potential paths.
5287 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5288 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5289 short_channel_id: 2,
5292 cltv_expiry_delta: 0,
5293 htlc_minimum_msat: 0,
5294 htlc_maximum_msat: 100_000,
5296 fee_proportional_millionths: 0,
5297 excess_data: Vec::new()
5299 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5300 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5301 short_channel_id: 7,
5304 cltv_expiry_delta: 0,
5305 htlc_minimum_msat: 0,
5306 htlc_maximum_msat: 100_000,
5308 fee_proportional_millionths: 0,
5309 excess_data: Vec::new()
5312 // Path via {node0, node2} is channels {1, 3, 5}.
5313 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5314 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5315 short_channel_id: 1,
5318 cltv_expiry_delta: 0,
5319 htlc_minimum_msat: 0,
5320 htlc_maximum_msat: 100_000,
5322 fee_proportional_millionths: 0,
5323 excess_data: Vec::new()
5325 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5326 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5327 short_channel_id: 3,
5330 cltv_expiry_delta: 0,
5331 htlc_minimum_msat: 0,
5332 htlc_maximum_msat: 100_000,
5334 fee_proportional_millionths: 0,
5335 excess_data: Vec::new()
5338 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5339 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5340 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5341 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5342 short_channel_id: 5,
5345 cltv_expiry_delta: 0,
5346 htlc_minimum_msat: 0,
5347 htlc_maximum_msat: 200_000,
5349 fee_proportional_millionths: 0,
5350 excess_data: Vec::new()
5353 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5354 // Add 100 sats to the capacities of {12, 13}, because these channels
5355 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5356 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5357 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5358 short_channel_id: 12,
5361 cltv_expiry_delta: 0,
5362 htlc_minimum_msat: 0,
5363 htlc_maximum_msat: 200_000,
5365 fee_proportional_millionths: 0,
5366 excess_data: Vec::new()
5368 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5369 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5370 short_channel_id: 13,
5373 cltv_expiry_delta: 0,
5374 htlc_minimum_msat: 0,
5375 htlc_maximum_msat: 200_000,
5377 fee_proportional_millionths: 0,
5378 excess_data: Vec::new()
5381 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5382 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5383 short_channel_id: 6,
5386 cltv_expiry_delta: 0,
5387 htlc_minimum_msat: 0,
5388 htlc_maximum_msat: 100_000,
5389 fee_base_msat: 1_000,
5390 fee_proportional_millionths: 0,
5391 excess_data: Vec::new()
5393 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5394 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5395 short_channel_id: 11,
5398 cltv_expiry_delta: 0,
5399 htlc_minimum_msat: 0,
5400 htlc_maximum_msat: 100_000,
5402 fee_proportional_millionths: 0,
5403 excess_data: Vec::new()
5406 // Path via {node7, node2} is channels {12, 13, 5}.
5407 // We already limited them to 200 sats (they are used twice for 100 sats).
5408 // Nothing to do here.
5411 // Now, attempt to route 180 sats.
5412 // Our algorithm should provide us with these 2 paths.
5413 let route_params = RouteParameters::from_payment_params_and_value(
5414 payment_params, 180_000);
5415 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5416 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5417 assert_eq!(route.paths.len(), 2);
5419 let mut total_value_transferred_msat = 0;
5420 let mut total_paid_msat = 0;
5421 for path in &route.paths {
5422 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5423 total_value_transferred_msat += path.final_value_msat();
5424 for hop in &path.hops {
5425 total_paid_msat += hop.fee_msat;
5428 // If we paid fee, this would be higher.
5429 assert_eq!(total_value_transferred_msat, 180_000);
5430 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5431 assert_eq!(total_fees_paid, 0);
5436 fn fees_on_mpp_route_test() {
5437 // This test makes sure that MPP algorithm properly takes into account
5438 // fees charged on the channels, by making the fees impactful:
5439 // if the fee is not properly accounted for, the behavior is different.
5440 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5441 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5442 let scorer = ln_test_utils::TestScorer::new();
5443 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5444 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5445 let config = UserConfig::default();
5446 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5447 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5450 // We need a route consisting of 2 paths:
5451 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5452 // We will route 200 sats, Each path will have 100 sats capacity.
5454 // This test is not particularly stable: e.g.,
5455 // there's a way to route via {node0, node2, node4}.
5456 // It works while pathfinding is deterministic, but can be broken otherwise.
5457 // It's fine to ignore this concern for now.
5459 // Disable other potential paths.
5460 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5461 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5462 short_channel_id: 2,
5465 cltv_expiry_delta: 0,
5466 htlc_minimum_msat: 0,
5467 htlc_maximum_msat: 100_000,
5469 fee_proportional_millionths: 0,
5470 excess_data: Vec::new()
5473 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5474 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5475 short_channel_id: 7,
5478 cltv_expiry_delta: 0,
5479 htlc_minimum_msat: 0,
5480 htlc_maximum_msat: 100_000,
5482 fee_proportional_millionths: 0,
5483 excess_data: Vec::new()
5486 // Path via {node0, node2} is channels {1, 3, 5}.
5487 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5488 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5489 short_channel_id: 1,
5492 cltv_expiry_delta: 0,
5493 htlc_minimum_msat: 0,
5494 htlc_maximum_msat: 100_000,
5496 fee_proportional_millionths: 0,
5497 excess_data: Vec::new()
5499 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5500 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5501 short_channel_id: 3,
5504 cltv_expiry_delta: 0,
5505 htlc_minimum_msat: 0,
5506 htlc_maximum_msat: 100_000,
5508 fee_proportional_millionths: 0,
5509 excess_data: Vec::new()
5512 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5513 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5514 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5515 short_channel_id: 5,
5518 cltv_expiry_delta: 0,
5519 htlc_minimum_msat: 0,
5520 htlc_maximum_msat: 100_000,
5522 fee_proportional_millionths: 0,
5523 excess_data: Vec::new()
5526 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5527 // All channels should be 100 sats capacity. But for the fee experiment,
5528 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5529 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5530 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5531 // so no matter how large are other channels,
5532 // the whole path will be limited by 100 sats with just these 2 conditions:
5533 // - channel 12 capacity is 250 sats
5534 // - fee for channel 6 is 150 sats
5535 // Let's test this by enforcing these 2 conditions and removing other limits.
5536 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5537 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5538 short_channel_id: 12,
5541 cltv_expiry_delta: 0,
5542 htlc_minimum_msat: 0,
5543 htlc_maximum_msat: 250_000,
5545 fee_proportional_millionths: 0,
5546 excess_data: Vec::new()
5548 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5549 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5550 short_channel_id: 13,
5553 cltv_expiry_delta: 0,
5554 htlc_minimum_msat: 0,
5555 htlc_maximum_msat: MAX_VALUE_MSAT,
5557 fee_proportional_millionths: 0,
5558 excess_data: Vec::new()
5561 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5562 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5563 short_channel_id: 6,
5566 cltv_expiry_delta: 0,
5567 htlc_minimum_msat: 0,
5568 htlc_maximum_msat: MAX_VALUE_MSAT,
5569 fee_base_msat: 150_000,
5570 fee_proportional_millionths: 0,
5571 excess_data: Vec::new()
5573 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5574 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5575 short_channel_id: 11,
5578 cltv_expiry_delta: 0,
5579 htlc_minimum_msat: 0,
5580 htlc_maximum_msat: MAX_VALUE_MSAT,
5582 fee_proportional_millionths: 0,
5583 excess_data: Vec::new()
5587 // Attempt to route more than available results in a failure.
5588 let route_params = RouteParameters::from_payment_params_and_value(
5589 payment_params.clone(), 210_000);
5590 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5591 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5592 &scorer, &Default::default(), &random_seed_bytes) {
5593 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5594 } else { panic!(); }
5598 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5599 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5600 max_total_routing_fee_msat: Some(149_999) };
5601 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5602 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5603 &scorer, &Default::default(), &random_seed_bytes) {
5604 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5605 } else { panic!(); }
5609 // Now, attempt to route 200 sats (exact amount we can route).
5610 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5611 max_total_routing_fee_msat: Some(150_000) };
5612 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5613 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5614 assert_eq!(route.paths.len(), 2);
5616 let mut total_amount_paid_msat = 0;
5617 for path in &route.paths {
5618 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5619 total_amount_paid_msat += path.final_value_msat();
5621 assert_eq!(total_amount_paid_msat, 200_000);
5622 assert_eq!(route.get_total_fees(), 150_000);
5627 fn mpp_with_last_hops() {
5628 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5629 // via a single last-hop route hint, we'd fail to route if we first collected routes
5630 // totaling close but not quite enough to fund the full payment.
5632 // This was because we considered last-hop hints to have exactly the sought payment amount
5633 // instead of the amount we were trying to collect, needlessly limiting our path searching
5634 // at the very first hop.
5636 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5637 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5638 // to only have the remaining to-collect amount in available liquidity.
5640 // This bug appeared in production in some specific channel configurations.
5641 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5642 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
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();
5646 let config = UserConfig::default();
5647 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
5648 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
5649 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5650 src_node_id: nodes[2],
5651 short_channel_id: 42,
5652 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5653 cltv_expiry_delta: 42,
5654 htlc_minimum_msat: None,
5655 htlc_maximum_msat: None,
5656 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5658 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5659 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5660 // would first use the no-fee route and then fail to find a path along the second route as
5661 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5662 // under 5% of our payment amount.
5663 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5664 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5665 short_channel_id: 1,
5668 cltv_expiry_delta: (5 << 4) | 5,
5669 htlc_minimum_msat: 0,
5670 htlc_maximum_msat: 99_000,
5671 fee_base_msat: u32::max_value(),
5672 fee_proportional_millionths: u32::max_value(),
5673 excess_data: Vec::new()
5675 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5676 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5677 short_channel_id: 2,
5680 cltv_expiry_delta: (5 << 4) | 3,
5681 htlc_minimum_msat: 0,
5682 htlc_maximum_msat: 99_000,
5683 fee_base_msat: u32::max_value(),
5684 fee_proportional_millionths: u32::max_value(),
5685 excess_data: Vec::new()
5687 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5688 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5689 short_channel_id: 4,
5692 cltv_expiry_delta: (4 << 4) | 1,
5693 htlc_minimum_msat: 0,
5694 htlc_maximum_msat: MAX_VALUE_MSAT,
5696 fee_proportional_millionths: 0,
5697 excess_data: Vec::new()
5699 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5700 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5701 short_channel_id: 13,
5703 flags: 0|2, // Channel disabled
5704 cltv_expiry_delta: (13 << 4) | 1,
5705 htlc_minimum_msat: 0,
5706 htlc_maximum_msat: MAX_VALUE_MSAT,
5708 fee_proportional_millionths: 2000000,
5709 excess_data: Vec::new()
5712 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5714 let route_params = RouteParameters::from_payment_params_and_value(
5715 payment_params, 100_000);
5716 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5717 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5718 assert_eq!(route.paths.len(), 2);
5719 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5720 // Paths are manually ordered ordered by SCID, so:
5721 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5722 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5723 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5724 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5725 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5726 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5727 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5728 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5729 assert_eq!(route.get_total_fees(), 1);
5730 assert_eq!(route.get_total_amount(), 100_000);
5734 fn drop_lowest_channel_mpp_route_test() {
5735 // This test checks that low-capacity channel is dropped when after
5736 // path finding we realize that we found more capacity than we need.
5737 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5738 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5739 let scorer = ln_test_utils::TestScorer::new();
5740 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5741 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5742 let config = UserConfig::default();
5743 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5744 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5746 .with_max_channel_saturation_power_of_half(0);
5748 // We need a route consisting of 3 paths:
5749 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5751 // The first and the second paths should be sufficient, but the third should be
5752 // cheaper, so that we select it but drop later.
5754 // First, we set limits on these (previously unlimited) channels.
5755 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5757 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5758 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5759 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5760 short_channel_id: 1,
5763 cltv_expiry_delta: 0,
5764 htlc_minimum_msat: 0,
5765 htlc_maximum_msat: 100_000,
5767 fee_proportional_millionths: 0,
5768 excess_data: Vec::new()
5770 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5771 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5772 short_channel_id: 3,
5775 cltv_expiry_delta: 0,
5776 htlc_minimum_msat: 0,
5777 htlc_maximum_msat: 50_000,
5779 fee_proportional_millionths: 0,
5780 excess_data: Vec::new()
5783 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5784 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5785 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5786 short_channel_id: 12,
5789 cltv_expiry_delta: 0,
5790 htlc_minimum_msat: 0,
5791 htlc_maximum_msat: 60_000,
5793 fee_proportional_millionths: 0,
5794 excess_data: Vec::new()
5796 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5797 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5798 short_channel_id: 13,
5801 cltv_expiry_delta: 0,
5802 htlc_minimum_msat: 0,
5803 htlc_maximum_msat: 60_000,
5805 fee_proportional_millionths: 0,
5806 excess_data: Vec::new()
5809 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5810 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5811 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5812 short_channel_id: 2,
5815 cltv_expiry_delta: 0,
5816 htlc_minimum_msat: 0,
5817 htlc_maximum_msat: 20_000,
5819 fee_proportional_millionths: 0,
5820 excess_data: Vec::new()
5822 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5823 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5824 short_channel_id: 4,
5827 cltv_expiry_delta: 0,
5828 htlc_minimum_msat: 0,
5829 htlc_maximum_msat: 20_000,
5831 fee_proportional_millionths: 0,
5832 excess_data: Vec::new()
5836 // Attempt to route more than available results in a failure.
5837 let route_params = RouteParameters::from_payment_params_and_value(
5838 payment_params.clone(), 150_000);
5839 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5840 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5841 &scorer, &Default::default(), &random_seed_bytes) {
5842 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5843 } else { panic!(); }
5847 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5848 // Our algorithm should provide us with these 3 paths.
5849 let route_params = RouteParameters::from_payment_params_and_value(
5850 payment_params.clone(), 125_000);
5851 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5852 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5853 assert_eq!(route.paths.len(), 3);
5854 let mut total_amount_paid_msat = 0;
5855 for path in &route.paths {
5856 assert_eq!(path.hops.len(), 2);
5857 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5858 total_amount_paid_msat += path.final_value_msat();
5860 assert_eq!(total_amount_paid_msat, 125_000);
5864 // Attempt to route without the last small cheap channel
5865 let route_params = RouteParameters::from_payment_params_and_value(
5866 payment_params, 90_000);
5867 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5868 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5869 assert_eq!(route.paths.len(), 2);
5870 let mut total_amount_paid_msat = 0;
5871 for path in &route.paths {
5872 assert_eq!(path.hops.len(), 2);
5873 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5874 total_amount_paid_msat += path.final_value_msat();
5876 assert_eq!(total_amount_paid_msat, 90_000);
5881 fn min_criteria_consistency() {
5882 // Test that we don't use an inconsistent metric between updating and walking nodes during
5883 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5884 // was updated with a different criterion from the heap sorting, resulting in loops in
5885 // calculated paths. We test for that specific case here.
5887 // We construct a network that looks like this:
5889 // node2 -1(3)2- node3
5893 // node1 -1(5)2- node4 -1(1)2- node6
5899 // We create a loop on the side of our real path - our destination is node 6, with a
5900 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5901 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5902 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5903 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5904 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5905 // "previous hop" being set to node 3, creating a loop in the path.
5906 let secp_ctx = Secp256k1::new();
5907 let logger = Arc::new(ln_test_utils::TestLogger::new());
5908 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5909 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5910 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5911 let scorer = ln_test_utils::TestScorer::new();
5912 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5913 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5914 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5916 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5917 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5918 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5919 short_channel_id: 6,
5922 cltv_expiry_delta: (6 << 4) | 0,
5923 htlc_minimum_msat: 0,
5924 htlc_maximum_msat: MAX_VALUE_MSAT,
5926 fee_proportional_millionths: 0,
5927 excess_data: Vec::new()
5929 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5931 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5932 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5933 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5934 short_channel_id: 5,
5937 cltv_expiry_delta: (5 << 4) | 0,
5938 htlc_minimum_msat: 0,
5939 htlc_maximum_msat: MAX_VALUE_MSAT,
5941 fee_proportional_millionths: 0,
5942 excess_data: Vec::new()
5944 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5946 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5947 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5948 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5949 short_channel_id: 4,
5952 cltv_expiry_delta: (4 << 4) | 0,
5953 htlc_minimum_msat: 0,
5954 htlc_maximum_msat: MAX_VALUE_MSAT,
5956 fee_proportional_millionths: 0,
5957 excess_data: Vec::new()
5959 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5961 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5962 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5963 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5964 short_channel_id: 3,
5967 cltv_expiry_delta: (3 << 4) | 0,
5968 htlc_minimum_msat: 0,
5969 htlc_maximum_msat: MAX_VALUE_MSAT,
5971 fee_proportional_millionths: 0,
5972 excess_data: Vec::new()
5974 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5976 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5977 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5978 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5979 short_channel_id: 2,
5982 cltv_expiry_delta: (2 << 4) | 0,
5983 htlc_minimum_msat: 0,
5984 htlc_maximum_msat: MAX_VALUE_MSAT,
5986 fee_proportional_millionths: 0,
5987 excess_data: Vec::new()
5990 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5991 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5992 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5993 short_channel_id: 1,
5996 cltv_expiry_delta: (1 << 4) | 0,
5997 htlc_minimum_msat: 100,
5998 htlc_maximum_msat: MAX_VALUE_MSAT,
6000 fee_proportional_millionths: 0,
6001 excess_data: Vec::new()
6003 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6006 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6007 let route_params = RouteParameters::from_payment_params_and_value(
6008 payment_params, 10_000);
6009 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6010 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6011 assert_eq!(route.paths.len(), 1);
6012 assert_eq!(route.paths[0].hops.len(), 3);
6014 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6015 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6016 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6017 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6018 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6019 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6021 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6022 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6023 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6024 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6025 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6026 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6028 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6029 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6030 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6031 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6032 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6033 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6039 fn exact_fee_liquidity_limit() {
6040 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6041 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6042 // we calculated fees on a higher value, resulting in us ignoring such paths.
6043 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6044 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6045 let scorer = ln_test_utils::TestScorer::new();
6046 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6047 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6048 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6050 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6052 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6053 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6054 short_channel_id: 2,
6057 cltv_expiry_delta: 0,
6058 htlc_minimum_msat: 0,
6059 htlc_maximum_msat: 85_000,
6061 fee_proportional_millionths: 0,
6062 excess_data: Vec::new()
6065 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6066 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6067 short_channel_id: 12,
6070 cltv_expiry_delta: (4 << 4) | 1,
6071 htlc_minimum_msat: 0,
6072 htlc_maximum_msat: 270_000,
6074 fee_proportional_millionths: 1000000,
6075 excess_data: Vec::new()
6079 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6080 // 200% fee charged channel 13 in the 1-to-2 direction.
6081 let mut route_params = RouteParameters::from_payment_params_and_value(
6082 payment_params, 90_000);
6083 route_params.max_total_routing_fee_msat = Some(90_000*2);
6084 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6085 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6086 assert_eq!(route.paths.len(), 1);
6087 assert_eq!(route.paths[0].hops.len(), 2);
6089 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6090 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6091 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6092 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6093 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6094 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6096 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6097 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6098 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6099 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6100 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6101 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6106 fn htlc_max_reduction_below_min() {
6107 // Test that if, while walking the graph, we reduce the value being sent to meet an
6108 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6109 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6110 // resulting in us thinking there is no possible path, even if other paths exist.
6111 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6112 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6113 let scorer = ln_test_utils::TestScorer::new();
6114 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6115 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6116 let config = UserConfig::default();
6117 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6118 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6121 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6122 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6123 // then try to send 90_000.
6124 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6125 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6126 short_channel_id: 2,
6129 cltv_expiry_delta: 0,
6130 htlc_minimum_msat: 0,
6131 htlc_maximum_msat: 80_000,
6133 fee_proportional_millionths: 0,
6134 excess_data: Vec::new()
6136 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6137 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6138 short_channel_id: 4,
6141 cltv_expiry_delta: (4 << 4) | 1,
6142 htlc_minimum_msat: 90_000,
6143 htlc_maximum_msat: MAX_VALUE_MSAT,
6145 fee_proportional_millionths: 0,
6146 excess_data: Vec::new()
6150 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6151 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6152 // expensive) channels 12-13 path.
6153 let mut route_params = RouteParameters::from_payment_params_and_value(
6154 payment_params, 90_000);
6155 route_params.max_total_routing_fee_msat = Some(90_000*2);
6156 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6157 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6158 assert_eq!(route.paths.len(), 1);
6159 assert_eq!(route.paths[0].hops.len(), 2);
6161 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6162 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6163 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6164 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6165 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6166 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6168 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6169 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6170 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6171 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6172 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6173 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6178 fn multiple_direct_first_hops() {
6179 // Previously we'd only ever considered one first hop path per counterparty.
6180 // However, as we don't restrict users to one channel per peer, we really need to support
6181 // looking at all first hop paths.
6182 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6183 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6184 // route over multiple channels with the same first hop.
6185 let secp_ctx = Secp256k1::new();
6186 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6187 let logger = Arc::new(ln_test_utils::TestLogger::new());
6188 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6189 let scorer = ln_test_utils::TestScorer::new();
6190 let config = UserConfig::default();
6191 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6192 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6194 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6195 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6198 let route_params = RouteParameters::from_payment_params_and_value(
6199 payment_params.clone(), 100_000);
6200 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6201 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6202 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6203 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6204 assert_eq!(route.paths.len(), 1);
6205 assert_eq!(route.paths[0].hops.len(), 1);
6207 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6208 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6209 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6212 let route_params = RouteParameters::from_payment_params_and_value(
6213 payment_params.clone(), 100_000);
6214 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6215 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6216 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6217 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6218 assert_eq!(route.paths.len(), 2);
6219 assert_eq!(route.paths[0].hops.len(), 1);
6220 assert_eq!(route.paths[1].hops.len(), 1);
6222 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6223 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6225 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6226 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6228 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6229 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6233 // If we have a bunch of outbound channels to the same node, where most are not
6234 // sufficient to pay the full payment, but one is, we should default to just using the
6235 // one single channel that has sufficient balance, avoiding MPP.
6237 // If we have several options above the 3xpayment value threshold, we should pick the
6238 // smallest of them, avoiding further fragmenting our available outbound balance to
6240 let route_params = RouteParameters::from_payment_params_and_value(
6241 payment_params, 100_000);
6242 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6243 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6244 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6245 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6246 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6247 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6248 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6249 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6250 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6251 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6252 assert_eq!(route.paths.len(), 1);
6253 assert_eq!(route.paths[0].hops.len(), 1);
6255 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6256 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6257 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6262 fn prefers_shorter_route_with_higher_fees() {
6263 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6264 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6265 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6267 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6268 let scorer = ln_test_utils::TestScorer::new();
6269 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6270 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6271 let route_params = RouteParameters::from_payment_params_and_value(
6272 payment_params.clone(), 100);
6273 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6274 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6275 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6277 assert_eq!(route.get_total_fees(), 100);
6278 assert_eq!(route.get_total_amount(), 100);
6279 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6281 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6282 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6283 let scorer = FixedPenaltyScorer::with_penalty(100);
6284 let route_params = RouteParameters::from_payment_params_and_value(
6285 payment_params, 100);
6286 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6287 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6288 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6290 assert_eq!(route.get_total_fees(), 300);
6291 assert_eq!(route.get_total_amount(), 100);
6292 assert_eq!(path, vec![2, 4, 7, 10]);
6295 struct BadChannelScorer {
6296 short_channel_id: u64,
6300 impl Writeable for BadChannelScorer {
6301 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6303 impl ScoreLookUp for BadChannelScorer {
6304 type ScoreParams = ();
6305 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6306 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6310 struct BadNodeScorer {
6315 impl Writeable for BadNodeScorer {
6316 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6319 impl ScoreLookUp for BadNodeScorer {
6320 type ScoreParams = ();
6321 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6322 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6327 fn avoids_routing_through_bad_channels_and_nodes() {
6328 let (secp_ctx, network, _, _, logger) = build_graph();
6329 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6330 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6331 let network_graph = network.read_only();
6333 // A path to nodes[6] exists when no penalties are applied to any channel.
6334 let scorer = ln_test_utils::TestScorer::new();
6335 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6336 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6337 let route_params = RouteParameters::from_payment_params_and_value(
6338 payment_params, 100);
6339 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6340 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6341 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6343 assert_eq!(route.get_total_fees(), 100);
6344 assert_eq!(route.get_total_amount(), 100);
6345 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6347 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6348 let scorer = BadChannelScorer { short_channel_id: 6 };
6349 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6350 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6351 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6353 assert_eq!(route.get_total_fees(), 300);
6354 assert_eq!(route.get_total_amount(), 100);
6355 assert_eq!(path, vec![2, 4, 7, 10]);
6357 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6358 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6359 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6360 &scorer, &Default::default(), &random_seed_bytes) {
6361 Err(LightningError { err, .. } ) => {
6362 assert_eq!(err, "Failed to find a path to the given destination");
6364 Ok(_) => panic!("Expected error"),
6369 fn total_fees_single_path() {
6371 paths: vec![Path { hops: vec![
6373 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6374 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6375 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6378 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6379 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6380 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6383 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6384 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6385 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6387 ], blinded_tail: None }],
6391 assert_eq!(route.get_total_fees(), 250);
6392 assert_eq!(route.get_total_amount(), 225);
6396 fn total_fees_multi_path() {
6398 paths: vec![Path { hops: vec![
6400 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6401 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6402 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6405 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6406 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6407 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6409 ], blinded_tail: None }, Path { hops: vec![
6411 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6412 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6413 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6416 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6417 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6418 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6420 ], blinded_tail: None }],
6424 assert_eq!(route.get_total_fees(), 200);
6425 assert_eq!(route.get_total_amount(), 300);
6429 fn total_empty_route_no_panic() {
6430 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6431 // would both panic if the route was completely empty. We test to ensure they return 0
6432 // here, even though its somewhat nonsensical as a route.
6433 let route = Route { paths: Vec::new(), route_params: None };
6435 assert_eq!(route.get_total_fees(), 0);
6436 assert_eq!(route.get_total_amount(), 0);
6440 fn limits_total_cltv_delta() {
6441 let (secp_ctx, network, _, _, logger) = build_graph();
6442 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6443 let network_graph = network.read_only();
6445 let scorer = ln_test_utils::TestScorer::new();
6447 // Make sure that generally there is at least one route available
6448 let feasible_max_total_cltv_delta = 1008;
6449 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6450 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6451 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6452 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6453 let route_params = RouteParameters::from_payment_params_and_value(
6454 feasible_payment_params, 100);
6455 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6456 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6457 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6458 assert_ne!(path.len(), 0);
6460 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6461 let fail_max_total_cltv_delta = 23;
6462 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6463 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6464 let route_params = RouteParameters::from_payment_params_and_value(
6465 fail_payment_params, 100);
6466 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6467 &Default::default(), &random_seed_bytes)
6469 Err(LightningError { err, .. } ) => {
6470 assert_eq!(err, "Failed to find a path to the given destination");
6472 Ok(_) => panic!("Expected error"),
6477 fn avoids_recently_failed_paths() {
6478 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6479 // randomly inserting channels into it until we can't find a route anymore.
6480 let (secp_ctx, network, _, _, logger) = build_graph();
6481 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6482 let network_graph = network.read_only();
6484 let scorer = ln_test_utils::TestScorer::new();
6485 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6486 .with_max_path_count(1);
6487 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6488 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6490 // We should be able to find a route initially, and then after we fail a few random
6491 // channels eventually we won't be able to any longer.
6492 let route_params = RouteParameters::from_payment_params_and_value(
6493 payment_params.clone(), 100);
6494 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6495 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6497 let route_params = RouteParameters::from_payment_params_and_value(
6498 payment_params.clone(), 100);
6499 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6500 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6502 for chan in route.paths[0].hops.iter() {
6503 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6505 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6506 % route.paths[0].hops.len();
6507 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6513 fn limits_path_length() {
6514 let (secp_ctx, network, _, _, logger) = build_line_graph();
6515 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6516 let network_graph = network.read_only();
6518 let scorer = ln_test_utils::TestScorer::new();
6519 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6520 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6522 // First check we can actually create a long route on this graph.
6523 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6524 let route_params = RouteParameters::from_payment_params_and_value(
6525 feasible_payment_params, 100);
6526 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6527 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6528 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6529 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6531 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6532 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6533 let route_params = RouteParameters::from_payment_params_and_value(
6534 fail_payment_params, 100);
6535 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6536 &Default::default(), &random_seed_bytes)
6538 Err(LightningError { err, .. } ) => {
6539 assert_eq!(err, "Failed to find a path to the given destination");
6541 Ok(_) => panic!("Expected error"),
6546 fn adds_and_limits_cltv_offset() {
6547 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6548 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6550 let scorer = ln_test_utils::TestScorer::new();
6552 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6553 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6554 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6555 let route_params = RouteParameters::from_payment_params_and_value(
6556 payment_params.clone(), 100);
6557 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6558 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6559 assert_eq!(route.paths.len(), 1);
6561 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6563 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6564 let mut route_default = route.clone();
6565 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6566 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6567 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6568 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6569 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6571 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6572 let mut route_limited = route.clone();
6573 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6574 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6575 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6576 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6577 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6581 fn adds_plausible_cltv_offset() {
6582 let (secp_ctx, network, _, _, logger) = build_graph();
6583 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6584 let network_graph = network.read_only();
6585 let network_nodes = network_graph.nodes();
6586 let network_channels = network_graph.channels();
6587 let scorer = ln_test_utils::TestScorer::new();
6588 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6589 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6590 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6592 let route_params = RouteParameters::from_payment_params_and_value(
6593 payment_params.clone(), 100);
6594 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6595 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6596 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6598 let mut path_plausibility = vec![];
6600 for p in route.paths {
6601 // 1. Select random observation point
6602 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6603 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6605 prng.process_in_place(&mut random_bytes);
6606 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6607 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6609 // 2. Calculate what CLTV expiry delta we would observe there
6610 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6612 // 3. Starting from the observation point, find candidate paths
6613 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6614 candidates.push_back((observation_point, vec![]));
6616 let mut found_plausible_candidate = false;
6618 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6619 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6620 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6621 found_plausible_candidate = true;
6622 break 'candidate_loop;
6626 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6627 for channel_id in &cur_node.channels {
6628 if let Some(channel_info) = network_channels.get(&channel_id) {
6629 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6630 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6631 if cur_path_cltv_deltas.iter().sum::<u32>()
6632 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6633 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6634 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6635 candidates.push_back((*next_id, new_path_cltv_deltas));
6643 path_plausibility.push(found_plausible_candidate);
6645 assert!(path_plausibility.iter().all(|x| *x));
6649 fn builds_correct_path_from_hops() {
6650 let (secp_ctx, network, _, _, logger) = build_graph();
6651 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6652 let network_graph = network.read_only();
6654 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6655 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6657 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6658 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6659 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6660 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6661 Arc::clone(&logger), &random_seed_bytes).unwrap();
6662 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6663 assert_eq!(hops.len(), route.paths[0].hops.len());
6664 for (idx, hop_pubkey) in hops.iter().enumerate() {
6665 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6670 fn avoids_saturating_channels() {
6671 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6672 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6673 let decay_params = ProbabilisticScoringDecayParameters::default();
6674 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6676 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6677 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6678 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6679 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6680 short_channel_id: 4,
6683 cltv_expiry_delta: (4 << 4) | 1,
6684 htlc_minimum_msat: 0,
6685 htlc_maximum_msat: 250_000_000,
6687 fee_proportional_millionths: 0,
6688 excess_data: Vec::new()
6690 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6691 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6692 short_channel_id: 13,
6695 cltv_expiry_delta: (13 << 4) | 1,
6696 htlc_minimum_msat: 0,
6697 htlc_maximum_msat: 250_000_000,
6699 fee_proportional_millionths: 0,
6700 excess_data: Vec::new()
6703 let config = UserConfig::default();
6704 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6705 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6707 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6708 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6709 // 100,000 sats is less than the available liquidity on each channel, set above.
6710 let route_params = RouteParameters::from_payment_params_and_value(
6711 payment_params, 100_000_000);
6712 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6713 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6714 assert_eq!(route.paths.len(), 2);
6715 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6716 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6719 #[cfg(not(feature = "no-std"))]
6720 pub(super) fn random_init_seed() -> u64 {
6721 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6722 use core::hash::{BuildHasher, Hasher};
6723 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6724 println!("Using seed of {}", seed);
6729 #[cfg(not(feature = "no-std"))]
6730 fn generate_routes() {
6731 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6733 let logger = ln_test_utils::TestLogger::new();
6734 let graph = match super::bench_utils::read_network_graph(&logger) {
6742 let params = ProbabilisticScoringFeeParameters::default();
6743 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6744 let features = super::Bolt11InvoiceFeatures::empty();
6746 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6750 #[cfg(not(feature = "no-std"))]
6751 fn generate_routes_mpp() {
6752 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6754 let logger = ln_test_utils::TestLogger::new();
6755 let graph = match super::bench_utils::read_network_graph(&logger) {
6763 let params = ProbabilisticScoringFeeParameters::default();
6764 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6765 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6767 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6771 #[cfg(not(feature = "no-std"))]
6772 fn generate_large_mpp_routes() {
6773 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6775 let logger = ln_test_utils::TestLogger::new();
6776 let graph = match super::bench_utils::read_network_graph(&logger) {
6784 let params = ProbabilisticScoringFeeParameters::default();
6785 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6786 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6788 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6792 fn honors_manual_penalties() {
6793 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6794 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6796 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6797 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6799 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6800 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6802 // First check set manual penalties are returned by the scorer.
6803 let usage = ChannelUsage {
6805 inflight_htlc_msat: 0,
6806 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6808 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6809 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6810 let network_graph = network_graph.read_only();
6811 let channels = network_graph.channels();
6812 let channel = channels.get(&5).unwrap();
6813 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
6814 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop {
6816 short_channel_id: 5,
6818 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
6820 // Then check we can get a normal route
6821 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6822 let route_params = RouteParameters::from_payment_params_and_value(
6823 payment_params, 100);
6824 let route = get_route(&our_id, &route_params, &network_graph, None,
6825 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6826 assert!(route.is_ok());
6828 // Then check that we can't get a route if we ban an intermediate node.
6829 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6830 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6831 assert!(route.is_err());
6833 // Finally make sure we can route again, when we remove the ban.
6834 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6835 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6836 assert!(route.is_ok());
6840 fn abide_by_route_hint_max_htlc() {
6841 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6842 // params in the final route.
6843 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6844 let netgraph = network_graph.read_only();
6845 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6846 let scorer = ln_test_utils::TestScorer::new();
6847 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6848 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6849 let config = UserConfig::default();
6851 let max_htlc_msat = 50_000;
6852 let route_hint_1 = RouteHint(vec![RouteHintHop {
6853 src_node_id: nodes[2],
6854 short_channel_id: 42,
6857 proportional_millionths: 0,
6859 cltv_expiry_delta: 10,
6860 htlc_minimum_msat: None,
6861 htlc_maximum_msat: Some(max_htlc_msat),
6863 let dest_node_id = ln_test_utils::pubkey(42);
6864 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6865 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6866 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6869 // Make sure we'll error if our route hints don't have enough liquidity according to their
6870 // htlc_maximum_msat.
6871 let mut route_params = RouteParameters::from_payment_params_and_value(
6872 payment_params, max_htlc_msat + 1);
6873 route_params.max_total_routing_fee_msat = None;
6874 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6875 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6878 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6879 } else { panic!(); }
6881 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6882 let mut route_hint_2 = route_hint_1.clone();
6883 route_hint_2.0[0].short_channel_id = 43;
6884 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6885 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6886 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6888 let mut route_params = RouteParameters::from_payment_params_and_value(
6889 payment_params, max_htlc_msat + 1);
6890 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6891 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6892 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6893 assert_eq!(route.paths.len(), 2);
6894 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6895 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6899 fn direct_channel_to_hints_with_max_htlc() {
6900 // Check that if we have a first hop channel peer that's connected to multiple provided route
6901 // hints, that we properly split the payment between the route hints if needed.
6902 let logger = Arc::new(ln_test_utils::TestLogger::new());
6903 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6904 let scorer = ln_test_utils::TestScorer::new();
6905 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6906 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6907 let config = UserConfig::default();
6909 let our_node_id = ln_test_utils::pubkey(42);
6910 let intermed_node_id = ln_test_utils::pubkey(43);
6911 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6913 let amt_msat = 900_000;
6914 let max_htlc_msat = 500_000;
6915 let route_hint_1 = RouteHint(vec![RouteHintHop {
6916 src_node_id: intermed_node_id,
6917 short_channel_id: 44,
6920 proportional_millionths: 0,
6922 cltv_expiry_delta: 10,
6923 htlc_minimum_msat: None,
6924 htlc_maximum_msat: Some(max_htlc_msat),
6926 src_node_id: intermed_node_id,
6927 short_channel_id: 45,
6930 proportional_millionths: 0,
6932 cltv_expiry_delta: 10,
6933 htlc_minimum_msat: None,
6934 // Check that later route hint max htlcs don't override earlier ones
6935 htlc_maximum_msat: Some(max_htlc_msat - 50),
6937 let mut route_hint_2 = route_hint_1.clone();
6938 route_hint_2.0[0].short_channel_id = 46;
6939 route_hint_2.0[1].short_channel_id = 47;
6940 let dest_node_id = ln_test_utils::pubkey(44);
6941 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6942 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6943 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6946 let route_params = RouteParameters::from_payment_params_and_value(
6947 payment_params, amt_msat);
6948 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6949 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6950 &Default::default(), &random_seed_bytes).unwrap();
6951 assert_eq!(route.paths.len(), 2);
6952 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6953 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6954 assert_eq!(route.get_total_amount(), amt_msat);
6956 // Re-run but with two first hop channels connected to the same route hint peers that must be
6958 let first_hops = vec![
6959 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6960 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6962 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6963 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6964 &Default::default(), &random_seed_bytes).unwrap();
6965 assert_eq!(route.paths.len(), 2);
6966 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6967 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6968 assert_eq!(route.get_total_amount(), amt_msat);
6970 // Make sure this works for blinded route hints.
6971 let blinded_path = BlindedPath {
6972 introduction_node_id: intermed_node_id,
6973 blinding_point: ln_test_utils::pubkey(42),
6975 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6976 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6979 let blinded_payinfo = BlindedPayInfo {
6981 fee_proportional_millionths: 0,
6982 htlc_minimum_msat: 1,
6983 htlc_maximum_msat: max_htlc_msat,
6984 cltv_expiry_delta: 10,
6985 features: BlindedHopFeatures::empty(),
6987 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
6988 let payment_params = PaymentParameters::blinded(vec![
6989 (blinded_payinfo.clone(), blinded_path.clone()),
6990 (blinded_payinfo.clone(), blinded_path.clone())])
6991 .with_bolt12_features(bolt12_features).unwrap();
6992 let route_params = RouteParameters::from_payment_params_and_value(
6993 payment_params, amt_msat);
6994 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6995 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6996 &Default::default(), &random_seed_bytes).unwrap();
6997 assert_eq!(route.paths.len(), 2);
6998 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6999 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7000 assert_eq!(route.get_total_amount(), amt_msat);
7004 fn blinded_route_ser() {
7005 let blinded_path_1 = BlindedPath {
7006 introduction_node_id: ln_test_utils::pubkey(42),
7007 blinding_point: ln_test_utils::pubkey(43),
7009 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7010 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7013 let blinded_path_2 = BlindedPath {
7014 introduction_node_id: ln_test_utils::pubkey(46),
7015 blinding_point: ln_test_utils::pubkey(47),
7017 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7018 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7021 // (De)serialize a Route with 1 blinded path out of two total paths.
7022 let mut route = Route { paths: vec![Path {
7023 hops: vec![RouteHop {
7024 pubkey: ln_test_utils::pubkey(50),
7025 node_features: NodeFeatures::empty(),
7026 short_channel_id: 42,
7027 channel_features: ChannelFeatures::empty(),
7029 cltv_expiry_delta: 0,
7030 maybe_announced_channel: true,
7032 blinded_tail: Some(BlindedTail {
7033 hops: blinded_path_1.blinded_hops,
7034 blinding_point: blinded_path_1.blinding_point,
7035 excess_final_cltv_expiry_delta: 40,
7036 final_value_msat: 100,
7038 hops: vec![RouteHop {
7039 pubkey: ln_test_utils::pubkey(51),
7040 node_features: NodeFeatures::empty(),
7041 short_channel_id: 43,
7042 channel_features: ChannelFeatures::empty(),
7044 cltv_expiry_delta: 0,
7045 maybe_announced_channel: true,
7046 }], blinded_tail: None }],
7049 let encoded_route = route.encode();
7050 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7051 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7052 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7054 // (De)serialize a Route with two paths, each containing a blinded tail.
7055 route.paths[1].blinded_tail = Some(BlindedTail {
7056 hops: blinded_path_2.blinded_hops,
7057 blinding_point: blinded_path_2.blinding_point,
7058 excess_final_cltv_expiry_delta: 41,
7059 final_value_msat: 101,
7061 let encoded_route = route.encode();
7062 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7063 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7064 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7068 fn blinded_path_inflight_processing() {
7069 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7070 // account for the blinded tail's final amount_msat.
7071 let mut inflight_htlcs = InFlightHtlcs::new();
7072 let blinded_path = BlindedPath {
7073 introduction_node_id: ln_test_utils::pubkey(43),
7074 blinding_point: ln_test_utils::pubkey(48),
7075 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7078 hops: vec![RouteHop {
7079 pubkey: ln_test_utils::pubkey(42),
7080 node_features: NodeFeatures::empty(),
7081 short_channel_id: 42,
7082 channel_features: ChannelFeatures::empty(),
7084 cltv_expiry_delta: 0,
7085 maybe_announced_channel: false,
7088 pubkey: blinded_path.introduction_node_id,
7089 node_features: NodeFeatures::empty(),
7090 short_channel_id: 43,
7091 channel_features: ChannelFeatures::empty(),
7093 cltv_expiry_delta: 0,
7094 maybe_announced_channel: false,
7096 blinded_tail: Some(BlindedTail {
7097 hops: blinded_path.blinded_hops,
7098 blinding_point: blinded_path.blinding_point,
7099 excess_final_cltv_expiry_delta: 0,
7100 final_value_msat: 200,
7103 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7104 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7105 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7109 fn blinded_path_cltv_shadow_offset() {
7110 // Make sure we add a shadow offset when sending to blinded paths.
7111 let blinded_path = BlindedPath {
7112 introduction_node_id: ln_test_utils::pubkey(43),
7113 blinding_point: ln_test_utils::pubkey(44),
7115 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7116 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7119 let mut route = Route { paths: vec![Path {
7120 hops: vec![RouteHop {
7121 pubkey: ln_test_utils::pubkey(42),
7122 node_features: NodeFeatures::empty(),
7123 short_channel_id: 42,
7124 channel_features: ChannelFeatures::empty(),
7126 cltv_expiry_delta: 0,
7127 maybe_announced_channel: false,
7130 pubkey: blinded_path.introduction_node_id,
7131 node_features: NodeFeatures::empty(),
7132 short_channel_id: 43,
7133 channel_features: ChannelFeatures::empty(),
7135 cltv_expiry_delta: 0,
7136 maybe_announced_channel: false,
7139 blinded_tail: Some(BlindedTail {
7140 hops: blinded_path.blinded_hops,
7141 blinding_point: blinded_path.blinding_point,
7142 excess_final_cltv_expiry_delta: 0,
7143 final_value_msat: 200,
7145 }], route_params: None};
7147 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7148 let (_, network_graph, _, _, _) = build_line_graph();
7149 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7150 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7151 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7155 fn simple_blinded_route_hints() {
7156 do_simple_blinded_route_hints(1);
7157 do_simple_blinded_route_hints(2);
7158 do_simple_blinded_route_hints(3);
7161 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7162 // Check that we can generate a route to a blinded path with the expected hops.
7163 let (secp_ctx, network, _, _, logger) = build_graph();
7164 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7165 let network_graph = network.read_only();
7167 let scorer = ln_test_utils::TestScorer::new();
7168 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7169 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7171 let mut blinded_path = BlindedPath {
7172 introduction_node_id: nodes[2],
7173 blinding_point: ln_test_utils::pubkey(42),
7174 blinded_hops: Vec::with_capacity(num_blinded_hops),
7176 for i in 0..num_blinded_hops {
7177 blinded_path.blinded_hops.push(
7178 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7181 let blinded_payinfo = BlindedPayInfo {
7183 fee_proportional_millionths: 500,
7184 htlc_minimum_msat: 1000,
7185 htlc_maximum_msat: 100_000_000,
7186 cltv_expiry_delta: 15,
7187 features: BlindedHopFeatures::empty(),
7190 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7191 let route_params = RouteParameters::from_payment_params_and_value(
7192 payment_params, 1001);
7193 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7194 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7195 assert_eq!(route.paths.len(), 1);
7196 assert_eq!(route.paths[0].hops.len(), 2);
7198 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7199 assert_eq!(tail.hops, blinded_path.blinded_hops);
7200 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7201 assert_eq!(tail.final_value_msat, 1001);
7203 let final_hop = route.paths[0].hops.last().unwrap();
7204 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
7205 if tail.hops.len() > 1 {
7206 assert_eq!(final_hop.fee_msat,
7207 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7208 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7210 assert_eq!(final_hop.fee_msat, 0);
7211 assert_eq!(final_hop.cltv_expiry_delta, 0);
7216 fn blinded_path_routing_errors() {
7217 // Check that we can generate a route to a blinded path with the expected hops.
7218 let (secp_ctx, network, _, _, logger) = build_graph();
7219 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7220 let network_graph = network.read_only();
7222 let scorer = ln_test_utils::TestScorer::new();
7223 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7224 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7226 let mut invalid_blinded_path = BlindedPath {
7227 introduction_node_id: nodes[2],
7228 blinding_point: ln_test_utils::pubkey(42),
7230 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7233 let blinded_payinfo = BlindedPayInfo {
7235 fee_proportional_millionths: 500,
7236 htlc_minimum_msat: 1000,
7237 htlc_maximum_msat: 100_000_000,
7238 cltv_expiry_delta: 15,
7239 features: BlindedHopFeatures::empty(),
7242 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7243 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7244 let payment_params = PaymentParameters::blinded(vec![
7245 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7246 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7247 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7248 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7249 &scorer, &Default::default(), &random_seed_bytes)
7251 Err(LightningError { err, .. }) => {
7252 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7254 _ => panic!("Expected error")
7257 invalid_blinded_path.introduction_node_id = our_id;
7258 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7259 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7260 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7261 &Default::default(), &random_seed_bytes)
7263 Err(LightningError { err, .. }) => {
7264 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7266 _ => panic!("Expected error")
7269 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7270 invalid_blinded_path.blinded_hops.clear();
7271 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7272 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7273 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7274 &Default::default(), &random_seed_bytes)
7276 Err(LightningError { err, .. }) => {
7277 assert_eq!(err, "0-hop blinded path provided");
7279 _ => panic!("Expected error")
7284 fn matching_intro_node_paths_provided() {
7285 // Check that if multiple blinded paths with the same intro node are provided in payment
7286 // parameters, we'll return the correct paths in the resulting MPP route.
7287 let (secp_ctx, network, _, _, logger) = build_graph();
7288 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7289 let network_graph = network.read_only();
7291 let scorer = ln_test_utils::TestScorer::new();
7292 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7293 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7294 let config = UserConfig::default();
7296 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7297 let blinded_path_1 = BlindedPath {
7298 introduction_node_id: nodes[2],
7299 blinding_point: ln_test_utils::pubkey(42),
7301 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7302 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7305 let blinded_payinfo_1 = BlindedPayInfo {
7307 fee_proportional_millionths: 0,
7308 htlc_minimum_msat: 0,
7309 htlc_maximum_msat: 30_000,
7310 cltv_expiry_delta: 0,
7311 features: BlindedHopFeatures::empty(),
7314 let mut blinded_path_2 = blinded_path_1.clone();
7315 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7316 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7317 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7319 let blinded_hints = vec![
7320 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7321 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7323 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7324 .with_bolt12_features(bolt12_features).unwrap();
7326 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7327 route_params.max_total_routing_fee_msat = Some(100_000);
7328 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7329 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7330 assert_eq!(route.paths.len(), 2);
7331 let mut total_amount_paid_msat = 0;
7332 for path in route.paths.into_iter() {
7333 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7334 if let Some(bt) = &path.blinded_tail {
7335 assert_eq!(bt.blinding_point,
7336 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7337 .map(|(_, bp)| bp.blinding_point).unwrap());
7338 } else { panic!(); }
7339 total_amount_paid_msat += path.final_value_msat();
7341 assert_eq!(total_amount_paid_msat, 100_000);
7345 fn direct_to_intro_node() {
7346 // This previously caused a debug panic in the router when asserting
7347 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7348 // direct channels we failed to account for the fee charged for use of the blinded path.
7351 // node0 -1(1)2 - node1
7352 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7353 // doesn't account for the blinded path fee.
7355 let secp_ctx = Secp256k1::new();
7356 let logger = Arc::new(ln_test_utils::TestLogger::new());
7357 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7358 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7359 let scorer = ln_test_utils::TestScorer::new();
7360 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7361 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7363 let amt_msat = 10_000_000;
7364 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7365 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7366 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7367 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7368 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7369 short_channel_id: 1,
7372 cltv_expiry_delta: 42,
7373 htlc_minimum_msat: 1_000,
7374 htlc_maximum_msat: 10_000_000,
7376 fee_proportional_millionths: 0,
7377 excess_data: Vec::new()
7379 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7380 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7381 short_channel_id: 1,
7384 cltv_expiry_delta: 42,
7385 htlc_minimum_msat: 1_000,
7386 htlc_maximum_msat: 10_000_000,
7388 fee_proportional_millionths: 0,
7389 excess_data: Vec::new()
7391 let first_hops = vec![
7392 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7394 let blinded_path = BlindedPath {
7395 introduction_node_id: nodes[1],
7396 blinding_point: ln_test_utils::pubkey(42),
7398 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7399 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7402 let blinded_payinfo = BlindedPayInfo {
7403 fee_base_msat: 1000,
7404 fee_proportional_millionths: 0,
7405 htlc_minimum_msat: 1000,
7406 htlc_maximum_msat: MAX_VALUE_MSAT,
7407 cltv_expiry_delta: 0,
7408 features: BlindedHopFeatures::empty(),
7410 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7412 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7414 let netgraph = network_graph.read_only();
7415 let route_params = RouteParameters::from_payment_params_and_value(
7416 payment_params.clone(), amt_msat);
7417 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7418 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7419 &Default::default(), &random_seed_bytes) {
7420 assert_eq!(err, "Failed to find a path to the given destination");
7421 } else { panic!("Expected error") }
7423 // Sending an exact amount accounting for the blinded path fee works.
7424 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7425 let route_params = RouteParameters::from_payment_params_and_value(
7426 payment_params, amt_minus_blinded_path_fee);
7427 let route = get_route(&nodes[0], &route_params, &netgraph,
7428 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7429 &Default::default(), &random_seed_bytes).unwrap();
7430 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7431 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7435 fn direct_to_matching_intro_nodes() {
7436 // This previously caused us to enter `unreachable` code in the following situation:
7437 // 1. We add a route candidate for intro_node contributing a high amount
7438 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7439 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7440 // amount, and update our route candidate for intro_node for the lower amount
7441 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7442 // lower contribution amount, but fail (this was previously caused by failure to account for
7443 // blinded path fees when adding first_hop<>intro_node candidates)
7444 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7445 // candidate still thinks its path is contributing the original higher amount. This caused us
7446 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7448 let secp_ctx = Secp256k1::new();
7449 let logger = Arc::new(ln_test_utils::TestLogger::new());
7450 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7451 let scorer = ln_test_utils::TestScorer::new();
7452 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7453 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7454 let config = UserConfig::default();
7456 // Values are taken from the fuzz input that uncovered this panic.
7457 let amt_msat = 21_7020_5185_1403_2640;
7458 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7459 let first_hops = vec![
7460 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7461 18446744073709551615)];
7463 let blinded_path = BlindedPath {
7464 introduction_node_id: nodes[1],
7465 blinding_point: ln_test_utils::pubkey(42),
7467 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7468 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7471 let blinded_payinfo = BlindedPayInfo {
7472 fee_base_msat: 5046_2720,
7473 fee_proportional_millionths: 0,
7474 htlc_minimum_msat: 4503_5996_2737_0496,
7475 htlc_maximum_msat: 45_0359_9627_3704_9600,
7476 cltv_expiry_delta: 0,
7477 features: BlindedHopFeatures::empty(),
7479 let mut blinded_hints = vec![
7480 (blinded_payinfo.clone(), blinded_path.clone()),
7481 (blinded_payinfo.clone(), blinded_path.clone()),
7483 blinded_hints[1].0.fee_base_msat = 419_4304;
7484 blinded_hints[1].0.fee_proportional_millionths = 257;
7485 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7486 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7487 blinded_hints[1].0.cltv_expiry_delta = 0;
7489 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7490 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7491 .with_bolt12_features(bolt12_features).unwrap();
7493 let netgraph = network_graph.read_only();
7494 let route_params = RouteParameters::from_payment_params_and_value(
7495 payment_params, amt_msat);
7496 let route = get_route(&nodes[0], &route_params, &netgraph,
7497 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7498 &Default::default(), &random_seed_bytes).unwrap();
7499 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7500 assert_eq!(route.get_total_amount(), amt_msat);
7504 fn we_are_intro_node_candidate_hops() {
7505 // This previously led to a panic in the router because we'd generate a Path with only a
7506 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7507 // where the origin node is the intro node. We now fully disallow considering candidate hops
7508 // where the origin node is the intro node.
7509 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7510 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7511 let scorer = ln_test_utils::TestScorer::new();
7512 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7513 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7514 let config = UserConfig::default();
7516 // Values are taken from the fuzz input that uncovered this panic.
7517 let amt_msat = 21_7020_5185_1423_0019;
7519 let blinded_path = BlindedPath {
7520 introduction_node_id: our_id,
7521 blinding_point: ln_test_utils::pubkey(42),
7523 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7524 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7527 let blinded_payinfo = BlindedPayInfo {
7528 fee_base_msat: 5052_9027,
7529 fee_proportional_millionths: 0,
7530 htlc_minimum_msat: 21_7020_5185_1423_0019,
7531 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7532 cltv_expiry_delta: 0,
7533 features: BlindedHopFeatures::empty(),
7535 let mut blinded_hints = vec![
7536 (blinded_payinfo.clone(), blinded_path.clone()),
7537 (blinded_payinfo.clone(), blinded_path.clone()),
7539 blinded_hints[1].1.introduction_node_id = nodes[6];
7541 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7542 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7543 .with_bolt12_features(bolt12_features.clone()).unwrap();
7545 let netgraph = network_graph.read_only();
7546 let route_params = RouteParameters::from_payment_params_and_value(
7547 payment_params, amt_msat);
7548 if let Err(LightningError { err, .. }) = get_route(
7549 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7551 assert_eq!(err, "Failed to find a path to the given destination");
7556 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7557 // This previously led to a debug panic in the router because we'd find an invalid Path with
7558 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7559 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7560 // the payment, when it was intended to only include the final value of the payment.
7561 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7562 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7563 let scorer = ln_test_utils::TestScorer::new();
7564 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7565 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7566 let config = UserConfig::default();
7568 // Values are taken from the fuzz input that uncovered this panic.
7569 let amt_msat = 21_7020_5185_1423_0019;
7571 let blinded_path = BlindedPath {
7572 introduction_node_id: our_id,
7573 blinding_point: ln_test_utils::pubkey(42),
7575 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7576 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7579 let blinded_payinfo = BlindedPayInfo {
7580 fee_base_msat: 10_4425_1395,
7581 fee_proportional_millionths: 0,
7582 htlc_minimum_msat: 21_7301_9934_9094_0931,
7583 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7584 cltv_expiry_delta: 0,
7585 features: BlindedHopFeatures::empty(),
7587 let mut blinded_hints = vec![
7588 (blinded_payinfo.clone(), blinded_path.clone()),
7589 (blinded_payinfo.clone(), blinded_path.clone()),
7590 (blinded_payinfo.clone(), blinded_path.clone()),
7592 blinded_hints[1].0.fee_base_msat = 5052_9027;
7593 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7594 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7596 blinded_hints[2].1.introduction_node_id = nodes[6];
7598 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7599 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7600 .with_bolt12_features(bolt12_features.clone()).unwrap();
7602 let netgraph = network_graph.read_only();
7603 let route_params = RouteParameters::from_payment_params_and_value(
7604 payment_params, amt_msat);
7605 if let Err(LightningError { err, .. }) = get_route(
7606 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7608 assert_eq!(err, "Failed to find a path to the given destination");
7613 fn min_htlc_overpay_violates_max_htlc() {
7614 do_min_htlc_overpay_violates_max_htlc(true);
7615 do_min_htlc_overpay_violates_max_htlc(false);
7617 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7618 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7619 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7620 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7621 // that the used liquidity for a hop was less than its available liquidity limit.
7622 let secp_ctx = Secp256k1::new();
7623 let logger = Arc::new(ln_test_utils::TestLogger::new());
7624 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7625 let scorer = ln_test_utils::TestScorer::new();
7626 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7627 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7628 let config = UserConfig::default();
7630 // Values are taken from the fuzz input that uncovered this panic.
7631 let amt_msat = 7_4009_8048;
7632 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7633 let first_hop_outbound_capacity = 2_7345_2000;
7634 let first_hops = vec![get_channel_details(
7635 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7636 first_hop_outbound_capacity
7639 let base_fee = 1_6778_3453;
7640 let htlc_min = 2_5165_8240;
7641 let payment_params = if blinded_payee {
7642 let blinded_path = BlindedPath {
7643 introduction_node_id: nodes[0],
7644 blinding_point: ln_test_utils::pubkey(42),
7646 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7647 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7650 let blinded_payinfo = BlindedPayInfo {
7651 fee_base_msat: base_fee,
7652 fee_proportional_millionths: 0,
7653 htlc_minimum_msat: htlc_min,
7654 htlc_maximum_msat: htlc_min * 1000,
7655 cltv_expiry_delta: 0,
7656 features: BlindedHopFeatures::empty(),
7658 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7659 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7660 .with_bolt12_features(bolt12_features.clone()).unwrap()
7662 let route_hint = RouteHint(vec![RouteHintHop {
7663 src_node_id: nodes[0],
7664 short_channel_id: 42,
7666 base_msat: base_fee,
7667 proportional_millionths: 0,
7669 cltv_expiry_delta: 10,
7670 htlc_minimum_msat: Some(htlc_min),
7671 htlc_maximum_msat: None,
7674 PaymentParameters::from_node_id(nodes[1], 42)
7675 .with_route_hints(vec![route_hint]).unwrap()
7676 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7679 let netgraph = network_graph.read_only();
7680 let route_params = RouteParameters::from_payment_params_and_value(
7681 payment_params, amt_msat);
7682 if let Err(LightningError { err, .. }) = get_route(
7683 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7684 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7686 assert_eq!(err, "Failed to find a path to the given destination");
7691 fn previously_used_liquidity_violates_max_htlc() {
7692 do_previously_used_liquidity_violates_max_htlc(true);
7693 do_previously_used_liquidity_violates_max_htlc(false);
7696 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7697 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7698 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7699 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7700 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7701 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7702 let secp_ctx = Secp256k1::new();
7703 let logger = Arc::new(ln_test_utils::TestLogger::new());
7704 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7705 let scorer = ln_test_utils::TestScorer::new();
7706 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7707 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7708 let config = UserConfig::default();
7710 // Values are taken from the fuzz input that uncovered this panic.
7711 let amt_msat = 52_4288;
7712 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7713 let first_hops = vec![get_channel_details(
7714 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7715 ), get_channel_details(
7716 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7719 let base_fees = [0, 425_9840, 0, 0];
7720 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7721 let payment_params = if blinded_payee {
7722 let blinded_path = BlindedPath {
7723 introduction_node_id: nodes[0],
7724 blinding_point: ln_test_utils::pubkey(42),
7726 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7727 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7730 let mut blinded_hints = Vec::new();
7731 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7732 blinded_hints.push((BlindedPayInfo {
7733 fee_base_msat: *base_fee,
7734 fee_proportional_millionths: 0,
7735 htlc_minimum_msat: *htlc_min,
7736 htlc_maximum_msat: htlc_min * 100,
7737 cltv_expiry_delta: 10,
7738 features: BlindedHopFeatures::empty(),
7739 }, blinded_path.clone()));
7741 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7742 PaymentParameters::blinded(blinded_hints.clone())
7743 .with_bolt12_features(bolt12_features.clone()).unwrap()
7745 let mut route_hints = Vec::new();
7746 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7747 route_hints.push(RouteHint(vec![RouteHintHop {
7748 src_node_id: nodes[0],
7749 short_channel_id: 42 + idx as u64,
7751 base_msat: *base_fee,
7752 proportional_millionths: 0,
7754 cltv_expiry_delta: 10,
7755 htlc_minimum_msat: Some(*htlc_min),
7756 htlc_maximum_msat: Some(htlc_min * 100),
7759 PaymentParameters::from_node_id(nodes[1], 42)
7760 .with_route_hints(route_hints).unwrap()
7761 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7764 let netgraph = network_graph.read_only();
7765 let route_params = RouteParameters::from_payment_params_and_value(
7766 payment_params, amt_msat);
7768 let route = get_route(
7769 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7770 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7772 assert_eq!(route.paths.len(), 1);
7773 assert_eq!(route.get_total_amount(), amt_msat);
7777 fn candidate_path_min() {
7778 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7779 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7780 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7781 // would add a connecting first_hop node that did not have enough contribution amount, leading
7782 // to a debug panic upon invalid path construction.
7783 let secp_ctx = Secp256k1::new();
7784 let logger = Arc::new(ln_test_utils::TestLogger::new());
7785 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7786 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7787 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7788 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7789 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7790 let config = UserConfig::default();
7792 // Values are taken from the fuzz input that uncovered this panic.
7793 let amt_msat = 7_4009_8048;
7794 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7795 let first_hops = vec![get_channel_details(
7796 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7799 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7800 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7801 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7802 short_channel_id: 6,
7805 cltv_expiry_delta: (6 << 4) | 0,
7806 htlc_minimum_msat: 0,
7807 htlc_maximum_msat: MAX_VALUE_MSAT,
7809 fee_proportional_millionths: 0,
7810 excess_data: Vec::new()
7812 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7814 let htlc_min = 2_5165_8240;
7815 let blinded_hints = vec![
7817 fee_base_msat: 1_6778_3453,
7818 fee_proportional_millionths: 0,
7819 htlc_minimum_msat: htlc_min,
7820 htlc_maximum_msat: htlc_min * 100,
7821 cltv_expiry_delta: 10,
7822 features: BlindedHopFeatures::empty(),
7824 introduction_node_id: nodes[0],
7825 blinding_point: ln_test_utils::pubkey(42),
7827 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7828 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7832 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7833 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7834 .with_bolt12_features(bolt12_features.clone()).unwrap();
7835 let route_params = RouteParameters::from_payment_params_and_value(
7836 payment_params, amt_msat);
7837 let netgraph = network_graph.read_only();
7839 if let Err(LightningError { err, .. }) = get_route(
7840 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7841 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7844 assert_eq!(err, "Failed to find a path to the given destination");
7849 fn path_contribution_includes_min_htlc_overpay() {
7850 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7851 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7852 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7853 // selection, both tested here.
7854 let secp_ctx = Secp256k1::new();
7855 let logger = Arc::new(ln_test_utils::TestLogger::new());
7856 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7857 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7858 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7859 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7860 let config = UserConfig::default();
7862 // Values are taken from the fuzz input that uncovered this panic.
7863 let amt_msat = 562_0000;
7864 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7865 let first_hops = vec![
7866 get_channel_details(
7867 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7871 let htlc_mins = [49_0000, 1125_0000];
7872 let payment_params = {
7873 let blinded_path = BlindedPath {
7874 introduction_node_id: nodes[0],
7875 blinding_point: ln_test_utils::pubkey(42),
7877 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7878 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7881 let mut blinded_hints = Vec::new();
7882 for htlc_min in htlc_mins.iter() {
7883 blinded_hints.push((BlindedPayInfo {
7885 fee_proportional_millionths: 0,
7886 htlc_minimum_msat: *htlc_min,
7887 htlc_maximum_msat: *htlc_min * 100,
7888 cltv_expiry_delta: 10,
7889 features: BlindedHopFeatures::empty(),
7890 }, blinded_path.clone()));
7892 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7893 PaymentParameters::blinded(blinded_hints.clone())
7894 .with_bolt12_features(bolt12_features.clone()).unwrap()
7897 let netgraph = network_graph.read_only();
7898 let route_params = RouteParameters::from_payment_params_and_value(
7899 payment_params, amt_msat);
7900 let route = get_route(
7901 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7902 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7905 assert_eq!(route.paths.len(), 1);
7906 assert_eq!(route.get_total_amount(), amt_msat);
7910 fn first_hop_preferred_over_hint() {
7911 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
7912 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
7913 let secp_ctx = Secp256k1::new();
7914 let logger = Arc::new(ln_test_utils::TestLogger::new());
7915 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7916 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7917 let scorer = ln_test_utils::TestScorer::new();
7918 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7919 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7920 let config = UserConfig::default();
7922 let amt_msat = 1_000_000;
7923 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
7925 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
7926 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7927 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
7928 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7929 short_channel_id: 1,
7932 cltv_expiry_delta: 42,
7933 htlc_minimum_msat: 1_000,
7934 htlc_maximum_msat: 10_000_000,
7936 fee_proportional_millionths: 0,
7937 excess_data: Vec::new()
7939 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7940 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7941 short_channel_id: 1,
7944 cltv_expiry_delta: 42,
7945 htlc_minimum_msat: 1_000,
7946 htlc_maximum_msat: 10_000_000,
7948 fee_proportional_millionths: 0,
7949 excess_data: Vec::new()
7952 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7953 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
7954 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7955 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7956 short_channel_id: 2,
7959 cltv_expiry_delta: 42,
7960 htlc_minimum_msat: 1_000,
7961 htlc_maximum_msat: 10_000_000,
7963 fee_proportional_millionths: 0,
7964 excess_data: Vec::new()
7966 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7967 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7968 short_channel_id: 2,
7971 cltv_expiry_delta: 42,
7972 htlc_minimum_msat: 1_000,
7973 htlc_maximum_msat: 10_000_000,
7975 fee_proportional_millionths: 0,
7976 excess_data: Vec::new()
7979 let dest_node_id = nodes[2];
7981 let route_hint = RouteHint(vec![RouteHintHop {
7982 src_node_id: our_node_id,
7983 short_channel_id: 44,
7986 proportional_millionths: 0,
7988 cltv_expiry_delta: 10,
7989 htlc_minimum_msat: None,
7990 htlc_maximum_msat: Some(5_000_000),
7993 src_node_id: nodes[0],
7994 short_channel_id: 45,
7997 proportional_millionths: 0,
7999 cltv_expiry_delta: 10,
8000 htlc_minimum_msat: None,
8001 htlc_maximum_msat: None,
8004 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8005 .with_route_hints(vec![route_hint]).unwrap()
8006 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8007 let route_params = RouteParameters::from_payment_params_and_value(
8008 payment_params, amt_msat);
8010 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8012 let first_hop = get_channel_details(Some(1), nodes[0],
8013 channelmanager::provided_init_features(&config), 999_999);
8014 let first_hops = vec![first_hop];
8016 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8017 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8018 &Default::default(), &random_seed_bytes).unwrap();
8019 assert_eq!(route.paths.len(), 1);
8020 assert_eq!(route.get_total_amount(), amt_msat);
8021 assert_eq!(route.paths[0].hops.len(), 2);
8022 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8023 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8024 assert_eq!(route.get_total_fees(), 123);
8026 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8027 // for a first hop channel.
8028 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8029 first_hop.outbound_scid_alias = Some(44);
8030 let first_hops = vec![first_hop];
8032 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8033 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8034 &Default::default(), &random_seed_bytes);
8035 assert!(route_res.is_err());
8037 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8038 // use the cheaper second hop of the route hint.
8039 let mut first_hop = get_channel_details(Some(1), nodes[0],
8040 channelmanager::provided_init_features(&config), 10_000_000);
8041 first_hop.outbound_scid_alias = Some(44);
8042 let first_hops = vec![first_hop];
8044 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8045 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8046 &Default::default(), &random_seed_bytes).unwrap();
8047 assert_eq!(route.paths.len(), 1);
8048 assert_eq!(route.get_total_amount(), amt_msat);
8049 assert_eq!(route.paths[0].hops.len(), 2);
8050 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8051 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8052 assert_eq!(route.get_total_fees(), 123);
8056 fn allow_us_being_first_hint() {
8057 // Check that we consider a route hint even if we are the src of the first hop.
8058 let secp_ctx = Secp256k1::new();
8059 let logger = Arc::new(ln_test_utils::TestLogger::new());
8060 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8061 let scorer = ln_test_utils::TestScorer::new();
8062 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8063 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8064 let config = UserConfig::default();
8066 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8068 let amt_msat = 1_000_000;
8069 let dest_node_id = nodes[1];
8071 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8072 let first_hops = vec![first_hop];
8074 let route_hint = RouteHint(vec![RouteHintHop {
8075 src_node_id: our_node_id,
8076 short_channel_id: 44,
8079 proportional_millionths: 0,
8081 cltv_expiry_delta: 10,
8082 htlc_minimum_msat: None,
8083 htlc_maximum_msat: None,
8086 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8087 .with_route_hints(vec![route_hint]).unwrap()
8088 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8090 let route_params = RouteParameters::from_payment_params_and_value(
8091 payment_params, amt_msat);
8094 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8095 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8096 &Default::default(), &random_seed_bytes).unwrap();
8098 assert_eq!(route.paths.len(), 1);
8099 assert_eq!(route.get_total_amount(), amt_msat);
8100 assert_eq!(route.get_total_fees(), 0);
8101 assert_eq!(route.paths[0].hops.len(), 1);
8103 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8107 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
8108 pub(crate) mod bench_utils {
8112 use bitcoin::hashes::Hash;
8113 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
8115 use crate::chain::transaction::OutPoint;
8116 use crate::routing::scoring::ScoreUpdate;
8117 use crate::sign::{EntropySource, KeysManager};
8118 use crate::ln::ChannelId;
8119 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
8120 use crate::ln::features::Bolt11InvoiceFeatures;
8121 use crate::routing::gossip::NetworkGraph;
8122 use crate::util::config::UserConfig;
8123 use crate::util::ser::ReadableArgs;
8124 use crate::util::test_utils::TestLogger;
8126 /// Tries to open a network graph file, or panics with a URL to fetch it.
8127 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
8128 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
8129 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
8130 .or_else(|_| { // Fall back to guessing based on the binary location
8131 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8132 let mut path = std::env::current_exe().unwrap();
8133 path.pop(); // lightning-...
8135 path.pop(); // debug
8136 path.pop(); // target
8137 path.push("lightning");
8138 path.push("net_graph-2023-01-18.bin");
8141 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8142 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8143 let mut path = std::env::current_exe().unwrap();
8144 path.pop(); // bench...
8146 path.pop(); // debug
8147 path.pop(); // target
8148 path.pop(); // bench
8149 path.push("lightning");
8150 path.push("net_graph-2023-01-18.bin");
8153 .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");
8154 #[cfg(require_route_graph_test)]
8155 return Ok(res.unwrap());
8156 #[cfg(not(require_route_graph_test))]
8160 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
8161 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
8164 pub(crate) fn payer_pubkey() -> PublicKey {
8165 let secp_ctx = Secp256k1::new();
8166 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8170 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8172 channel_id: ChannelId::new_zero(),
8173 counterparty: ChannelCounterparty {
8174 features: channelmanager::provided_init_features(&UserConfig::default()),
8176 unspendable_punishment_reserve: 0,
8177 forwarding_info: None,
8178 outbound_htlc_minimum_msat: None,
8179 outbound_htlc_maximum_msat: None,
8181 funding_txo: Some(OutPoint {
8182 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8185 short_channel_id: Some(1),
8186 inbound_scid_alias: None,
8187 outbound_scid_alias: None,
8188 channel_value_satoshis: 10_000_000_000,
8190 balance_msat: 10_000_000_000,
8191 outbound_capacity_msat: 10_000_000_000,
8192 next_outbound_htlc_minimum_msat: 0,
8193 next_outbound_htlc_limit_msat: 10_000_000_000,
8194 inbound_capacity_msat: 0,
8195 unspendable_punishment_reserve: None,
8196 confirmations_required: None,
8197 confirmations: None,
8198 force_close_spend_delay: None,
8200 is_channel_ready: true,
8203 inbound_htlc_minimum_msat: None,
8204 inbound_htlc_maximum_msat: None,
8206 feerate_sat_per_1000_weight: None,
8207 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
8211 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8212 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8213 starting_amount: u64, route_count: usize,
8214 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8215 let payer = payer_pubkey();
8216 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8217 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8219 let nodes = graph.read_only().nodes().clone();
8220 let mut route_endpoints = Vec::new();
8221 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
8222 // with some routes we picked being un-routable.
8223 for _ in 0..route_count * 3 / 2 {
8225 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8226 let src = PublicKey::from_slice(nodes.unordered_keys()
8227 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8228 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8229 let dst = PublicKey::from_slice(nodes.unordered_keys()
8230 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8231 let params = PaymentParameters::from_node_id(dst, 42)
8232 .with_bolt11_features(features.clone()).unwrap();
8233 let first_hop = first_hop(src);
8234 let amt_msat = starting_amount + seed % 1_000_000;
8235 let route_params = RouteParameters::from_payment_params_and_value(
8236 params.clone(), amt_msat);
8238 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8239 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8241 // ...and seed the scorer with success and failure data...
8242 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8243 let mut score_amt = seed % 1_000_000_000;
8245 // Generate fail/success paths for a wider range of potential amounts with
8246 // MPP enabled to give us a chance to apply penalties for more potential
8248 let mpp_features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
8249 let params = PaymentParameters::from_node_id(dst, 42)
8250 .with_bolt11_features(mpp_features).unwrap();
8251 let route_params = RouteParameters::from_payment_params_and_value(
8252 params.clone(), score_amt);
8253 let route_res = get_route(&payer, &route_params, &graph.read_only(),
8254 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
8255 &random_seed_bytes);
8256 if let Ok(route) = route_res {
8257 for path in route.paths {
8258 if seed & 0x80 == 0 {
8259 scorer.payment_path_successful(&path);
8261 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
8262 scorer.payment_path_failed(&path, short_channel_id);
8264 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8268 // If we couldn't find a path with a higer amount, reduce and try again.
8272 route_endpoints.push((first_hop, params, amt_msat));
8278 // Because we've changed channel scores, it's possible we'll take different routes to the
8279 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
8280 // requires a too-high CLTV delta.
8281 route_endpoints.retain(|(first_hop, params, amt_msat)| {
8282 let route_params = RouteParameters::from_payment_params_and_value(
8283 params.clone(), *amt_msat);
8284 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8285 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
8287 route_endpoints.truncate(route_count);
8288 assert_eq!(route_endpoints.len(), route_count);
8296 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8297 use crate::sign::{EntropySource, KeysManager};
8298 use crate::ln::channelmanager;
8299 use crate::ln::features::Bolt11InvoiceFeatures;
8300 use crate::routing::gossip::NetworkGraph;
8301 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
8302 use crate::util::config::UserConfig;
8303 use crate::util::logger::{Logger, Record};
8304 use crate::util::test_utils::TestLogger;
8306 use criterion::Criterion;
8308 struct DummyLogger {}
8309 impl Logger for DummyLogger {
8310 fn log(&self, _record: Record) {}
8313 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8314 let logger = TestLogger::new();
8315 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8316 let scorer = FixedPenaltyScorer::with_penalty(0);
8317 generate_routes(bench, &network_graph, scorer, &Default::default(),
8318 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8321 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8322 let logger = TestLogger::new();
8323 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8324 let scorer = FixedPenaltyScorer::with_penalty(0);
8325 generate_routes(bench, &network_graph, scorer, &Default::default(),
8326 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8327 "generate_mpp_routes_with_zero_penalty_scorer");
8330 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8331 let logger = TestLogger::new();
8332 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8333 let params = ProbabilisticScoringFeeParameters::default();
8334 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8335 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8336 "generate_routes_with_probabilistic_scorer");
8339 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8340 let logger = TestLogger::new();
8341 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8342 let params = ProbabilisticScoringFeeParameters::default();
8343 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8344 generate_routes(bench, &network_graph, scorer, ¶ms,
8345 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8346 "generate_mpp_routes_with_probabilistic_scorer");
8349 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8350 let logger = TestLogger::new();
8351 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8352 let params = ProbabilisticScoringFeeParameters::default();
8353 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8354 generate_routes(bench, &network_graph, scorer, ¶ms,
8355 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8356 "generate_large_mpp_routes_with_probabilistic_scorer");
8359 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8360 let logger = TestLogger::new();
8361 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8362 let mut params = ProbabilisticScoringFeeParameters::default();
8363 params.linear_success_probability = false;
8364 let scorer = ProbabilisticScorer::new(
8365 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8366 generate_routes(bench, &network_graph, scorer, ¶ms,
8367 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8368 "generate_routes_with_nonlinear_probabilistic_scorer");
8371 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8372 let logger = TestLogger::new();
8373 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8374 let mut params = ProbabilisticScoringFeeParameters::default();
8375 params.linear_success_probability = false;
8376 let scorer = ProbabilisticScorer::new(
8377 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8378 generate_routes(bench, &network_graph, scorer, ¶ms,
8379 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8380 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8383 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8384 let logger = TestLogger::new();
8385 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8386 let mut params = ProbabilisticScoringFeeParameters::default();
8387 params.linear_success_probability = false;
8388 let scorer = ProbabilisticScorer::new(
8389 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8390 generate_routes(bench, &network_graph, scorer, ¶ms,
8391 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8392 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8395 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8396 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8397 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8398 bench_name: &'static str,
8400 let payer = bench_utils::payer_pubkey();
8401 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8402 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8404 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8405 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8407 // ...then benchmark finding paths between the nodes we learned.
8409 bench.bench_function(bench_name, |b| b.iter(|| {
8410 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8411 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8412 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8413 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());