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: &'a 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 the required difference in HTLC CLTV expiry between the [`Self::source`] and the
1142 /// next-hop for an HTLC taking this hop.
1144 /// This is the time that the node(s) in this hop have to claim the HTLC on-chain if the
1145 /// next-hop goes on chain with a payment preimage.
1147 pub fn cltv_expiry_delta(&self) -> u32 {
1149 CandidateRouteHop::FirstHop { .. } => 0,
1150 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1151 CandidateRouteHop::PrivateHop { hint, .. } => hint.cltv_expiry_delta as u32,
1152 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1153 CandidateRouteHop::OneHopBlinded { .. } => 0,
1157 /// Returns the minimum amount that can be sent over this hop, in millisatoshis.
1159 pub fn htlc_minimum_msat(&self) -> u64 {
1161 CandidateRouteHop::FirstHop { details, .. } => details.next_outbound_htlc_minimum_msat,
1162 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1163 CandidateRouteHop::PrivateHop { hint, .. } => hint.htlc_minimum_msat.unwrap_or(0),
1164 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1165 CandidateRouteHop::OneHopBlinded { .. } => 0,
1169 /// Returns the fees that must be paid to route an HTLC over this channel.
1171 pub fn fees(&self) -> RoutingFees {
1173 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1174 base_msat: 0, proportional_millionths: 0,
1176 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1177 CandidateRouteHop::PrivateHop { hint, .. } => hint.fees,
1178 CandidateRouteHop::Blinded { hint, .. } => {
1180 base_msat: hint.0.fee_base_msat,
1181 proportional_millionths: hint.0.fee_proportional_millionths
1184 CandidateRouteHop::OneHopBlinded { .. } =>
1185 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1189 fn effective_capacity(&self) -> EffectiveCapacity {
1191 CandidateRouteHop::FirstHop { details, .. } => EffectiveCapacity::ExactLiquidity {
1192 liquidity_msat: details.next_outbound_htlc_limit_msat,
1194 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1195 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. } =>
1196 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1197 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. } =>
1198 EffectiveCapacity::Infinite,
1199 CandidateRouteHop::Blinded { hint, .. } =>
1200 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1201 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1205 /// Returns an ID describing the given hop.
1207 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1209 fn id(&self) -> CandidateHopId {
1211 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1212 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1213 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1216 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1218 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1224 /// Returns the source node id of current hop.
1226 /// Source node id refers to the node forwarding the HTLC through this hop.
1228 /// For [`Self::FirstHop`] we return payer's node id.
1230 pub fn source(&self) -> NodeId {
1232 CandidateRouteHop::FirstHop { payer_node_id, .. } => **payer_node_id,
1233 CandidateRouteHop::PublicHop { info, .. } => *info.source(),
1234 CandidateRouteHop::PrivateHop { hint, .. } => hint.src_node_id.into(),
1235 CandidateRouteHop::Blinded { hint, .. } => hint.1.introduction_node_id.into(),
1236 CandidateRouteHop::OneHopBlinded { hint, .. } => hint.1.introduction_node_id.into(),
1239 /// Returns the target node id of this hop, if known.
1241 /// Target node id refers to the node receiving the HTLC after this hop.
1243 /// For [`Self::Blinded`] we return `None` because the ultimate destination after the blinded
1244 /// path is unknown.
1246 /// For [`Self::OneHopBlinded`] we return `None` because the target is the same as the source,
1247 /// and such a return value would be somewhat nonsensical.
1249 pub fn target(&self) -> Option<NodeId> {
1251 CandidateRouteHop::FirstHop { details, .. } => Some(details.counterparty.node_id.into()),
1252 CandidateRouteHop::PublicHop { info, .. } => Some(*info.target()),
1253 CandidateRouteHop::PrivateHop { target_node_id, .. } => Some(**target_node_id),
1254 CandidateRouteHop::Blinded { .. } => None,
1255 CandidateRouteHop::OneHopBlinded { .. } => None,
1260 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1262 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1264 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1265 /// isn't guaranteed to be unique at all.
1267 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1268 /// difficult-to-use API.
1269 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1270 enum CandidateHopId {
1271 /// Contains (scid, src_node_id < target_node_id)
1273 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1278 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1279 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1281 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1282 EffectiveCapacity::Infinite => u64::max_value(),
1283 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1284 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1285 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1286 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1287 // expected to have been generated from up-to-date capacity information.
1288 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1289 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1290 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1294 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1295 -> bool where I1::Item: PartialEq<I2::Item> {
1297 let a = iter_a.next();
1298 let b = iter_b.next();
1299 if a.is_none() && b.is_none() { return true; }
1300 if a.is_none() || b.is_none() { return false; }
1301 if a.unwrap().ne(&b.unwrap()) { return false; }
1305 /// It's useful to keep track of the hops associated with the fees required to use them,
1306 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1307 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1308 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1310 struct PathBuildingHop<'a> {
1311 candidate: CandidateRouteHop<'a>,
1314 /// All the fees paid *after* this channel on the way to the destination
1315 next_hops_fee_msat: u64,
1316 /// Fee paid for the use of the current channel (see candidate.fees()).
1317 /// The value will be actually deducted from the counterparty balance on the previous link.
1318 hop_use_fee_msat: u64,
1319 /// Used to compare channels when choosing the for routing.
1320 /// Includes paying for the use of a hop and the following hops, as well as
1321 /// an estimated cost of reaching this hop.
1322 /// Might get stale when fees are recomputed. Primarily for internal use.
1323 total_fee_msat: u64,
1324 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1325 /// walk and may be invalid thereafter.
1326 path_htlc_minimum_msat: u64,
1327 /// All penalties incurred from this channel on the way to the destination, as calculated using
1328 /// channel scoring.
1329 path_penalty_msat: u64,
1330 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1331 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1332 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1333 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1334 /// avoid processing them again.
1335 was_processed: bool,
1336 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1337 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1338 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1339 // value_contribution_msat, which requires tracking it here. See comments below where it is
1340 // used for more info.
1341 value_contribution_msat: u64,
1344 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1345 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1346 let mut debug_struct = f.debug_struct("PathBuildingHop");
1348 .field("node_id", &self.candidate.target())
1349 .field("short_channel_id", &self.candidate.short_channel_id())
1350 .field("total_fee_msat", &self.total_fee_msat)
1351 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1352 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1353 .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)))
1354 .field("path_penalty_msat", &self.path_penalty_msat)
1355 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1356 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1357 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1358 let debug_struct = debug_struct
1359 .field("value_contribution_msat", &self.value_contribution_msat);
1360 debug_struct.finish()
1364 // Instantiated with a list of hops with correct data in them collected during path finding,
1365 // an instance of this struct should be further modified only via given methods.
1367 struct PaymentPath<'a> {
1368 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1371 impl<'a> PaymentPath<'a> {
1372 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1373 fn get_value_msat(&self) -> u64 {
1374 self.hops.last().unwrap().0.fee_msat
1377 fn get_path_penalty_msat(&self) -> u64 {
1378 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1381 fn get_total_fee_paid_msat(&self) -> u64 {
1382 if self.hops.len() < 1 {
1386 // Can't use next_hops_fee_msat because it gets outdated.
1387 for (i, (hop, _)) in self.hops.iter().enumerate() {
1388 if i != self.hops.len() - 1 {
1389 result += hop.fee_msat;
1395 fn get_cost_msat(&self) -> u64 {
1396 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1399 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1400 // to change fees may result in an inconsistency.
1402 // Sometimes we call this function right after constructing a path which is inconsistent in
1403 // that it the value being transferred has decreased while we were doing path finding, leading
1404 // to the fees being paid not lining up with the actual limits.
1406 // Note that this function is not aware of the available_liquidity limit, and thus does not
1407 // support increasing the value being transferred beyond what was selected during the initial
1410 // Returns the amount that this path contributes to the total payment value, which may be greater
1411 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1412 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1413 let mut extra_contribution_msat = 0;
1414 let mut total_fee_paid_msat = 0 as u64;
1415 for i in (0..self.hops.len()).rev() {
1416 let last_hop = i == self.hops.len() - 1;
1418 // For non-last-hop, this value will represent the fees paid on the current hop. It
1419 // will consist of the fees for the use of the next hop, and extra fees to match
1420 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1421 let mut cur_hop_fees_msat = 0;
1423 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1426 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1427 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1428 cur_hop.path_penalty_msat += extra_contribution_msat;
1429 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1430 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1431 // set it too high just to maliciously take more fees by exploiting this
1432 // match htlc_minimum_msat logic.
1433 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1434 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1435 // Note that there is a risk that *previous hops* (those closer to us, as we go
1436 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1438 // This might make us end up with a broken route, although this should be super-rare
1439 // in practice, both because of how healthy channels look like, and how we pick
1440 // channels in add_entry.
1441 // Also, this can't be exploited more heavily than *announce a free path and fail
1443 cur_hop_transferred_amount_msat += extra_fees_msat;
1445 // We remember and return the extra fees on the final hop to allow accounting for
1446 // them in the path's value contribution.
1448 extra_contribution_msat = extra_fees_msat;
1450 total_fee_paid_msat += extra_fees_msat;
1451 cur_hop_fees_msat += extra_fees_msat;
1456 // Final hop is a special case: it usually has just value_msat (by design), but also
1457 // it still could overpay for the htlc_minimum_msat.
1458 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1460 // Propagate updated fees for the use of the channels to one hop back, where they
1461 // will be actually paid (fee_msat). The last hop is handled above separately.
1462 cur_hop.fee_msat = cur_hop_fees_msat;
1465 // Fee for the use of the current hop which will be deducted on the previous hop.
1466 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1467 // this channel is free for us.
1469 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1470 cur_hop.hop_use_fee_msat = new_fee;
1471 total_fee_paid_msat += new_fee;
1473 // It should not be possible because this function is called only to reduce the
1474 // value. In that case, compute_fee was already called with the same fees for
1475 // larger amount and there was no overflow.
1480 value_msat + extra_contribution_msat
1485 /// Calculate the fees required to route the given amount over a channel with the given fees.
1486 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1487 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1488 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1492 /// Calculate the fees required to route the given amount over a channel with the given fees,
1493 /// saturating to [`u64::max_value`].
1494 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1495 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1496 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1497 .saturating_add(channel_fees.base_msat as u64)
1500 /// The default `features` we assume for a node in a route, when no `features` are known about that
1503 /// Default features are:
1504 /// * variable_length_onion_optional
1505 fn default_node_features() -> NodeFeatures {
1506 let mut features = NodeFeatures::empty();
1507 features.set_variable_length_onion_optional();
1511 struct LoggedPayeePubkey(Option<PublicKey>);
1512 impl fmt::Display for LoggedPayeePubkey {
1513 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1516 "payee node id ".fmt(f)?;
1520 "blinded payee".fmt(f)
1526 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1527 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1528 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1530 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1531 "blinded route hint with introduction node id ".fmt(f)?;
1532 hint.1.introduction_node_id.fmt(f)?;
1533 " and blinding point ".fmt(f)?;
1534 hint.1.blinding_point.fmt(f)
1536 CandidateRouteHop::FirstHop { .. } => {
1537 "first hop with SCID ".fmt(f)?;
1538 self.0.short_channel_id().unwrap().fmt(f)
1540 CandidateRouteHop::PrivateHop { .. } => {
1541 "route hint with SCID ".fmt(f)?;
1542 self.0.short_channel_id().unwrap().fmt(f)
1546 self.0.short_channel_id().unwrap().fmt(f)
1553 fn sort_first_hop_channels(
1554 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1555 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1557 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1558 // most like to use.
1560 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1561 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1564 // Second, because simply always sorting in descending order would always use our largest
1565 // available outbound capacity, needlessly fragmenting our available channel capacities,
1566 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1567 // which have enough, but not too much, capacity for the payment.
1569 // Available outbound balances factor in liquidity already reserved for previously found paths.
1570 channels.sort_unstable_by(|chan_a, chan_b| {
1571 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1572 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1573 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1574 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1575 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1576 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1577 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1578 // Sort in descending order
1579 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1581 // Sort in ascending order
1582 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1587 /// Finds a route from us (payer) to the given target node (payee).
1589 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1590 /// in the given [`RouteParameters::payment_params`].
1591 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1593 /// Private routing paths between a public node and the target may be included in the `payee` field
1594 /// of [`RouteParameters::payment_params`].
1596 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1597 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1598 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1600 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1601 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1602 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1606 /// Panics if first_hops contains channels without `short_channel_id`s;
1607 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1609 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1610 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1611 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1612 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1613 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1614 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1615 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1616 ) -> Result<Route, LightningError>
1617 where L::Target: Logger, GL::Target: Logger {
1618 let graph_lock = network_graph.read_only();
1619 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1620 scorer, score_params, random_seed_bytes)?;
1621 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1625 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1626 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1627 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1628 _random_seed_bytes: &[u8; 32]
1629 ) -> Result<Route, LightningError>
1630 where L::Target: Logger {
1632 let payment_params = &route_params.payment_params;
1633 let final_value_msat = route_params.final_value_msat;
1634 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1635 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1636 // so use a dummy id for this in the blinded case.
1637 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1638 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1639 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1640 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1641 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1643 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1644 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1646 if our_node_id == maybe_dummy_payee_node_id {
1647 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1650 if final_value_msat > MAX_VALUE_MSAT {
1651 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1654 if final_value_msat == 0 {
1655 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1658 match &payment_params.payee {
1659 Payee::Clear { route_hints, node_id, .. } => {
1660 for route in route_hints.iter() {
1661 for hop in &route.0 {
1662 if hop.src_node_id == *node_id {
1663 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1668 Payee::Blinded { route_hints, .. } => {
1669 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1670 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});
1672 for (_, blinded_path) in route_hints.iter() {
1673 if blinded_path.blinded_hops.len() == 0 {
1674 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1675 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1676 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1677 } else if blinded_path.blinded_hops.len() == 1 &&
1678 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1679 && p.introduction_node_id != blinded_path.introduction_node_id)
1681 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1686 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1687 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1688 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});
1691 // The general routing idea is the following:
1692 // 1. Fill first/last hops communicated by the caller.
1693 // 2. Attempt to construct a path from payer to payee for transferring
1694 // any ~sufficient (described later) value.
1695 // If succeed, remember which channels were used and how much liquidity they have available,
1696 // so that future paths don't rely on the same liquidity.
1697 // 3. Proceed to the next step if:
1698 // - we hit the recommended target value;
1699 // - OR if we could not construct a new path. Any next attempt will fail too.
1700 // Otherwise, repeat step 2.
1701 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1702 // (not recommended value).
1703 // 5. If yes, proceed. If not, fail routing.
1704 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1705 // transferred up to the transfer target value.
1706 // 7. Reduce the value of the last path until we are sending only the target value.
1707 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1708 // them so that we're not sending two HTLCs along the same path.
1710 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1711 // distance from the payee
1713 // We are not a faithful Dijkstra's implementation because we can change values which impact
1714 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1715 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1716 // the value we are currently attempting to send over a path, we simply reduce the value being
1717 // sent along the path for any hops after that channel. This may imply that later fees (which
1718 // we've already tabulated) are lower because a smaller value is passing through the channels
1719 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1720 // channels which were selected earlier (and which may still be used for other paths without a
1721 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1724 // One potentially problematic case for this algorithm would be if there are many
1725 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1726 // graph walking), we may never find a path which is not liquidity-limited and has lower
1727 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1728 // Because we only consider paths with at least 5% of the total value being sent, the damage
1729 // from such a case should be limited, however this could be further reduced in the future by
1730 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1731 // limits for the purposes of fee calculation.
1733 // Alternatively, we could store more detailed path information in the heap (targets, below)
1734 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1735 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1736 // and practically (as we would need to store dynamically-allocated path information in heap
1737 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1738 // results of such an algorithm would likely be biased towards lower-value paths.
1740 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1741 // outside of our current search value, running a path search more times to gather candidate
1742 // paths at different values. While this may be acceptable, further path searches may increase
1743 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1744 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1745 // the same time, remaining generic across different payment values.
1747 let network_channels = network_graph.channels();
1748 let network_nodes = network_graph.nodes();
1750 if payment_params.max_path_count == 0 {
1751 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1754 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1755 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1757 let allow_mpp = if payment_params.max_path_count == 1 {
1759 } else if payment_params.payee.supports_basic_mpp() {
1761 } else if let Some(payee) = payee_node_id_opt {
1762 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1763 |info| info.features.supports_basic_mpp()))
1766 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1768 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1769 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1770 if allow_mpp { "with" } else { "without" },
1771 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1772 max_total_routing_fee_msat);
1775 // Prepare the data we'll use for payee-to-payer search by
1776 // inserting first hops suggested by the caller as targets.
1777 // Our search will then attempt to reach them while traversing from the payee node.
1778 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1779 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1780 if let Some(hops) = first_hops {
1782 if chan.get_outbound_payment_scid().is_none() {
1783 panic!("first_hops should be filled in with usable channels, not pending ones");
1785 if chan.counterparty.node_id == *our_node_pubkey {
1786 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1789 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1790 .or_insert(Vec::new())
1793 if first_hop_targets.is_empty() {
1794 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1798 let mut private_hop_key_cache = HashMap::with_capacity(
1799 payment_params.payee.unblinded_route_hints().iter().map(|path| path.0.len()).sum()
1802 // Because we store references to private hop node_ids in `dist`, below, we need them to exist
1803 // (as `NodeId`, not `PublicKey`) for the lifetime of `dist`. Thus, we calculate all the keys
1804 // we'll need here and simply fetch them when routing.
1805 private_hop_key_cache.insert(maybe_dummy_payee_pk, NodeId::from_pubkey(&maybe_dummy_payee_pk));
1806 for route in payment_params.payee.unblinded_route_hints().iter() {
1807 for hop in route.0.iter() {
1808 private_hop_key_cache.insert(hop.src_node_id, NodeId::from_pubkey(&hop.src_node_id));
1812 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1813 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1814 // adding duplicate entries when we find a better path to a given node.
1815 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1817 // Map from node_id to information about the best current path to that node, including feerate
1819 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1821 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1822 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1823 // htlc_minimum with extra fees while still finding a cheaper path.
1824 let mut hit_minimum_limit;
1826 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1827 // We start with a path_value of the exact amount we want, and if that generates a route we may
1828 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1829 // amount we want in total across paths, selecting the best subset at the end.
1830 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1831 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1832 let mut path_value_msat = final_value_msat;
1834 // Routing Fragmentation Mitigation heuristic:
1836 // Routing fragmentation across many payment paths increases the overall routing
1837 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1838 // Taking too many smaller paths also increases the chance of payment failure.
1839 // Thus to avoid this effect, we require from our collected links to provide
1840 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1841 // This requirement is currently set to be 1/max_path_count of the payment
1842 // value to ensure we only ever return routes that do not violate this limit.
1843 let minimal_value_contribution_msat: u64 = if allow_mpp {
1844 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1849 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1850 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1851 // drop the requirement by setting this to 0.
1852 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1854 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1855 // determine if the channel can be used by additional MPP paths or to inform path finding
1856 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1857 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1859 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1860 HashMap::with_capacity(network_nodes.len());
1862 // Keeping track of how much value we already collected across other paths. Helps to decide
1863 // when we want to stop looking for new paths.
1864 let mut already_collected_value_msat = 0;
1866 for (_, channels) in first_hop_targets.iter_mut() {
1867 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1871 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1872 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1874 // Remember how many candidates we ignored to allow for some logging afterwards.
1875 let mut num_ignored_value_contribution: u32 = 0;
1876 let mut num_ignored_path_length_limit: u32 = 0;
1877 let mut num_ignored_cltv_delta_limit: u32 = 0;
1878 let mut num_ignored_previously_failed: u32 = 0;
1879 let mut num_ignored_total_fee_limit: u32 = 0;
1880 let mut num_ignored_avoid_overpayment: u32 = 0;
1881 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
1883 macro_rules! add_entry {
1884 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
1885 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1886 // since that value has to be transferred over this channel.
1887 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1888 ( $candidate: expr, $next_hops_fee_msat: expr,
1889 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1890 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1891 // We "return" whether we updated the path at the end, and how much we can route via
1892 // this channel, via this:
1893 let mut hop_contribution_amt_msat = None;
1894 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1895 // practice these cases should be caught earlier:
1896 // - for regular channels at channel announcement (TODO)
1897 // - for first and last hops early in get_route
1898 let src_node_id = $candidate.source();
1899 if Some(src_node_id) != $candidate.target() {
1900 let scid_opt = $candidate.short_channel_id();
1901 let effective_capacity = $candidate.effective_capacity();
1902 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1904 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1905 // It may be misleading because we might later choose to reduce the value transferred
1906 // over these channels, and the channel which was insufficient might become sufficient.
1907 // Worst case: we drop a good channel here because it can't cover the high following
1908 // fees caused by one expensive channel, but then this channel could have been used
1909 // if the amount being transferred over this path is lower.
1910 // We do this for now, but this is a subject for removal.
1911 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1912 let used_liquidity_msat = used_liquidities
1913 .get(&$candidate.id())
1914 .map_or(0, |used_liquidity_msat| {
1915 available_value_contribution_msat = available_value_contribution_msat
1916 .saturating_sub(*used_liquidity_msat);
1917 *used_liquidity_msat
1920 // Verify the liquidity offered by this channel complies to the minimal contribution.
1921 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1922 // Do not consider candidate hops that would exceed the maximum path length.
1923 let path_length_to_node = $next_hops_path_length + 1;
1924 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1926 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1927 // In order to already account for some of the privacy enhancing random CLTV
1928 // expiry delta offset we add on top later, we subtract a rough estimate
1929 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1930 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1931 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1932 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1933 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1934 .saturating_add($candidate.cltv_expiry_delta());
1935 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1937 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1938 // Includes paying fees for the use of the following channels.
1939 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1940 Some(result) => result,
1941 // Can't overflow due to how the values were computed right above.
1942 None => unreachable!(),
1944 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1945 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1946 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1948 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1949 let may_overpay_to_meet_path_minimum_msat =
1950 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1951 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
1952 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1953 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
1955 let payment_failed_on_this_channel = scid_opt.map_or(false,
1956 |scid| payment_params.previously_failed_channels.contains(&scid));
1958 let (should_log_candidate, first_hop_details) = match $candidate {
1959 CandidateRouteHop::FirstHop { details, .. } => (true, Some(details)),
1960 CandidateRouteHop::PrivateHop { .. } => (true, None),
1961 CandidateRouteHop::Blinded { .. } => (true, None),
1962 CandidateRouteHop::OneHopBlinded { .. } => (true, None),
1966 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1967 // bother considering this channel. If retrying with recommended_value_msat may
1968 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1969 // around again with a higher amount.
1970 if !contributes_sufficient_value {
1971 if should_log_candidate {
1972 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1974 if let Some(details) = first_hop_details {
1976 "First hop candidate next_outbound_htlc_limit_msat: {}",
1977 details.next_outbound_htlc_limit_msat,
1981 num_ignored_value_contribution += 1;
1982 } else if exceeds_max_path_length {
1983 if should_log_candidate {
1984 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1986 num_ignored_path_length_limit += 1;
1987 } else if exceeds_cltv_delta_limit {
1988 if should_log_candidate {
1989 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1991 if let Some(_) = first_hop_details {
1993 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
1994 hop_total_cltv_delta,
1995 max_total_cltv_expiry_delta,
1999 num_ignored_cltv_delta_limit += 1;
2000 } else if payment_failed_on_this_channel {
2001 if should_log_candidate {
2002 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
2004 num_ignored_previously_failed += 1;
2005 } else if may_overpay_to_meet_path_minimum_msat {
2006 if should_log_candidate {
2008 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
2009 LoggedCandidateHop(&$candidate));
2011 if let Some(details) = first_hop_details {
2013 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2014 details.next_outbound_htlc_minimum_msat,
2018 num_ignored_avoid_overpayment += 1;
2019 hit_minimum_limit = true;
2020 } else if over_path_minimum_msat {
2021 // Note that low contribution here (limited by available_liquidity_msat)
2022 // might violate htlc_minimum_msat on the hops which are next along the
2023 // payment path (upstream to the payee). To avoid that, we recompute
2024 // path fees knowing the final path contribution after constructing it.
2025 let curr_min = cmp::max(
2026 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2028 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2029 .saturating_add(curr_min);
2030 let hm_entry = dist.entry(src_node_id);
2031 let old_entry = hm_entry.or_insert_with(|| {
2032 // If there was previously no known way to access the source node
2033 // (recall it goes payee-to-payer) of short_channel_id, first add a
2034 // semi-dummy record just to compute the fees to reach the source node.
2035 // This will affect our decision on selecting short_channel_id
2036 // as a way to reach the $candidate.target() node.
2038 candidate: $candidate.clone(),
2040 next_hops_fee_msat: u64::max_value(),
2041 hop_use_fee_msat: u64::max_value(),
2042 total_fee_msat: u64::max_value(),
2043 path_htlc_minimum_msat,
2044 path_penalty_msat: u64::max_value(),
2045 was_processed: false,
2046 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2047 value_contribution_msat,
2051 #[allow(unused_mut)] // We only use the mut in cfg(test)
2052 let mut should_process = !old_entry.was_processed;
2053 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2055 // In test/fuzzing builds, we do extra checks to make sure the skipping
2056 // of already-seen nodes only happens in cases we expect (see below).
2057 if !should_process { should_process = true; }
2061 let mut hop_use_fee_msat = 0;
2062 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2064 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2065 // will have the same effective-fee
2066 if src_node_id != our_node_id {
2067 // Note that `u64::max_value` means we'll always fail the
2068 // `old_entry.total_fee_msat > total_fee_msat` check below
2069 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2070 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2073 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2074 if total_fee_msat > max_total_routing_fee_msat {
2075 if should_log_candidate {
2076 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2078 if let Some(_) = first_hop_details {
2080 "First hop candidate routing fee: {}. Limit: {}",
2082 max_total_routing_fee_msat,
2086 num_ignored_total_fee_limit += 1;
2088 let channel_usage = ChannelUsage {
2089 amount_msat: amount_to_transfer_over_msat,
2090 inflight_htlc_msat: used_liquidity_msat,
2093 let channel_penalty_msat =
2094 scorer.channel_penalty_msat($candidate,
2097 let path_penalty_msat = $next_hops_path_penalty_msat
2098 .saturating_add(channel_penalty_msat);
2099 let new_graph_node = RouteGraphNode {
2100 node_id: src_node_id,
2101 lowest_fee_to_node: total_fee_msat,
2102 total_cltv_delta: hop_total_cltv_delta,
2103 value_contribution_msat,
2104 path_htlc_minimum_msat,
2106 path_length_to_node,
2109 // Update the way of reaching $candidate.source()
2110 // with the given short_channel_id (from $candidate.target()),
2111 // if this way is cheaper than the already known
2112 // (considering the cost to "reach" this channel from the route destination,
2113 // the cost of using this channel,
2114 // and the cost of routing to the source node of this channel).
2115 // Also, consider that htlc_minimum_msat_difference, because we might end up
2116 // paying it. Consider the following exploit:
2117 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2118 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2119 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2120 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2122 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2123 // but it may require additional tracking - we don't want to double-count
2124 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2125 // can't use something that may decrease on future hops.
2126 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2127 .saturating_add(old_entry.path_penalty_msat);
2128 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2129 .saturating_add(path_penalty_msat);
2131 if !old_entry.was_processed && new_cost < old_cost {
2132 targets.push(new_graph_node);
2133 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2134 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2135 old_entry.total_fee_msat = total_fee_msat;
2136 old_entry.candidate = $candidate.clone();
2137 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2138 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2139 old_entry.path_penalty_msat = path_penalty_msat;
2140 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2142 old_entry.value_contribution_msat = value_contribution_msat;
2144 hop_contribution_amt_msat = Some(value_contribution_msat);
2145 } else if old_entry.was_processed && new_cost < old_cost {
2146 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2148 // If we're skipping processing a node which was previously
2149 // processed even though we found another path to it with a
2150 // cheaper fee, check that it was because the second path we
2151 // found (which we are processing now) has a lower value
2152 // contribution due to an HTLC minimum limit.
2154 // e.g. take a graph with two paths from node 1 to node 2, one
2155 // through channel A, and one through channel B. Channel A and
2156 // B are both in the to-process heap, with their scores set by
2157 // a higher htlc_minimum than fee.
2158 // Channel A is processed first, and the channels onwards from
2159 // node 1 are added to the to-process heap. Thereafter, we pop
2160 // Channel B off of the heap, note that it has a much more
2161 // restrictive htlc_maximum_msat, and recalculate the fees for
2162 // all of node 1's channels using the new, reduced, amount.
2164 // This would be bogus - we'd be selecting a higher-fee path
2165 // with a lower htlc_maximum_msat instead of the one we'd
2166 // already decided to use.
2167 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2169 value_contribution_msat + path_penalty_msat <
2170 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2177 if should_log_candidate {
2179 "Ignoring {} due to its htlc_minimum_msat limit.",
2180 LoggedCandidateHop(&$candidate));
2182 if let Some(details) = first_hop_details {
2184 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2185 details.next_outbound_htlc_minimum_msat,
2189 num_ignored_htlc_minimum_msat_limit += 1;
2193 hop_contribution_amt_msat
2197 let default_node_features = default_node_features();
2199 // Find ways (channels with destination) to reach a given node and store them
2200 // in the corresponding data structures (routing graph etc).
2201 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2202 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2203 // This data can later be helpful to optimize routing (pay lower fees).
2204 macro_rules! add_entries_to_cheapest_to_target_node {
2205 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
2206 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
2207 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2208 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2209 let was_processed = elem.was_processed;
2210 elem.was_processed = true;
2213 // Entries are added to dist in add_entry!() when there is a channel from a node.
2214 // Because there are no channels from payee, it will not have a dist entry at this point.
2215 // If we're processing any other node, it is always be the result of a channel from it.
2216 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2221 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2222 for details in first_channels {
2223 let candidate = CandidateRouteHop::FirstHop {
2224 details, payer_node_id: &our_node_id,
2226 add_entry!(&candidate, $fee_to_target_msat,
2227 $next_hops_value_contribution,
2228 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
2229 $next_hops_cltv_delta, $next_hops_path_length);
2233 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2236 &default_node_features
2239 if !features.requires_unknown_bits() {
2240 for chan_id in $node.channels.iter() {
2241 let chan = network_channels.get(chan_id).unwrap();
2242 if !chan.features.requires_unknown_bits() {
2243 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2244 if first_hops.is_none() || *source != our_node_id {
2245 if directed_channel.direction().enabled {
2246 let candidate = CandidateRouteHop::PublicHop {
2247 info: directed_channel,
2248 short_channel_id: *chan_id,
2250 add_entry!(&candidate,
2251 $fee_to_target_msat,
2252 $next_hops_value_contribution,
2253 $next_hops_path_htlc_minimum_msat,
2254 $next_hops_path_penalty_msat,
2255 $next_hops_cltv_delta, $next_hops_path_length);
2266 let mut payment_paths = Vec::<PaymentPath>::new();
2268 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2269 'paths_collection: loop {
2270 // For every new path, start from scratch, except for used_liquidities, which
2271 // helps to avoid reusing previously selected paths in future iterations.
2274 hit_minimum_limit = false;
2276 // If first hop is a private channel and the only way to reach the payee, this is the only
2277 // place where it could be added.
2278 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2279 for details in first_channels {
2280 let candidate = CandidateRouteHop::FirstHop {
2281 details, payer_node_id: &our_node_id,
2283 let added = add_entry!(&candidate, 0, path_value_msat,
2284 0, 0u64, 0, 0).is_some();
2285 log_trace!(logger, "{} direct route to payee via {}",
2286 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2290 // Add the payee as a target, so that the payee-to-payer
2291 // search algorithm knows what to start with.
2292 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2293 // The payee is not in our network graph, so nothing to add here.
2294 // There is still a chance of reaching them via last_hops though,
2295 // so don't yet fail the payment here.
2296 // If not, targets.pop() will not even let us enter the loop in step 2.
2299 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2304 // If a caller provided us with last hops, add them to routing targets. Since this happens
2305 // earlier than general path finding, they will be somewhat prioritized, although currently
2306 // it matters only if the fees are exactly the same.
2307 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2308 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2309 let have_intro_node_in_graph =
2310 // Only add the hops in this route to our candidate set if either
2311 // we have a direct channel to the first hop or the first hop is
2312 // in the regular network graph.
2313 first_hop_targets.get(&intro_node_id).is_some() ||
2314 network_nodes.get(&intro_node_id).is_some();
2315 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2316 let candidate = if hint.1.blinded_hops.len() == 1 {
2317 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2318 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2319 let mut path_contribution_msat = path_value_msat;
2320 if let Some(hop_used_msat) = add_entry!(&candidate,
2321 0, path_contribution_msat, 0, 0_u64, 0, 0)
2323 path_contribution_msat = hop_used_msat;
2325 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2326 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2328 for details in first_channels {
2329 let first_hop_candidate = CandidateRouteHop::FirstHop {
2330 details, payer_node_id: &our_node_id,
2332 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2336 let path_min = candidate.htlc_minimum_msat().saturating_add(
2337 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2338 add_entry!(&first_hop_candidate, blinded_path_fee,
2339 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2340 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2344 for route in payment_params.payee.unblinded_route_hints().iter()
2345 .filter(|route| !route.0.is_empty())
2347 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2348 let first_hop_src_is_reachable =
2349 // Only add the hops in this route to our candidate set if either we are part of
2350 // the first hop, we have a direct channel to the first hop, or the first hop is in
2351 // the regular network graph.
2352 our_node_id == first_hop_src_id ||
2353 first_hop_targets.get(&first_hop_src_id).is_some() ||
2354 network_nodes.get(&first_hop_src_id).is_some();
2355 if first_hop_src_is_reachable {
2356 // We start building the path from reverse, i.e., from payee
2357 // to the first RouteHintHop in the path.
2358 let hop_iter = route.0.iter().rev();
2359 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2360 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2361 let mut hop_used = true;
2362 let mut aggregate_next_hops_fee_msat: u64 = 0;
2363 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2364 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2365 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2366 let mut aggregate_next_hops_path_length: u8 = 0;
2367 let mut aggregate_path_contribution_msat = path_value_msat;
2369 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2370 let target = private_hop_key_cache.get(&prev_hop_id).unwrap();
2372 if let Some(first_channels) = first_hop_targets.get(&target) {
2373 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2374 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2375 hop.short_channel_id);
2380 let candidate = network_channels
2381 .get(&hop.short_channel_id)
2382 .and_then(|channel| channel.as_directed_to(&target))
2383 .map(|(info, _)| CandidateRouteHop::PublicHop {
2385 short_channel_id: hop.short_channel_id,
2387 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop, target_node_id: target });
2389 if let Some(hop_used_msat) = add_entry!(&candidate,
2390 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2391 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2392 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2394 aggregate_path_contribution_msat = hop_used_msat;
2396 // If this hop was not used then there is no use checking the preceding
2397 // hops in the RouteHint. We can break by just searching for a direct
2398 // channel between last checked hop and first_hop_targets.
2402 let used_liquidity_msat = used_liquidities
2403 .get(&candidate.id()).copied()
2405 let channel_usage = ChannelUsage {
2406 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2407 inflight_htlc_msat: used_liquidity_msat,
2408 effective_capacity: candidate.effective_capacity(),
2410 let channel_penalty_msat = scorer.channel_penalty_msat(
2411 &candidate, channel_usage, score_params
2413 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2414 .saturating_add(channel_penalty_msat);
2416 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2417 .saturating_add(hop.cltv_expiry_delta as u32);
2419 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2422 // Searching for a direct channel between last checked hop and first_hop_targets
2423 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2424 sort_first_hop_channels(first_channels, &used_liquidities,
2425 recommended_value_msat, our_node_pubkey);
2426 for details in first_channels {
2427 let first_hop_candidate = CandidateRouteHop::FirstHop {
2428 details, payer_node_id: &our_node_id,
2430 add_entry!(&first_hop_candidate,
2431 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2432 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2433 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2441 // In the next values of the iterator, the aggregate fees already reflects
2442 // the sum of value sent from payer (final_value_msat) and routing fees
2443 // for the last node in the RouteHint. We need to just add the fees to
2444 // route through the current node so that the preceding node (next iteration)
2446 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2447 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2448 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2450 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2451 // this route hint's source node to forward said min over this channel.
2452 aggregate_next_hops_path_htlc_minimum_msat = {
2453 let curr_htlc_min = cmp::max(
2454 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2456 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2457 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2460 if idx == route.0.len() - 1 {
2461 // The last hop in this iterator is the first hop in
2462 // overall RouteHint.
2463 // If this hop connects to a node with which we have a direct channel,
2464 // ignore the network graph and, if the last hop was added, add our
2465 // direct channel to the candidate set.
2467 // Note that we *must* check if the last hop was added as `add_entry`
2468 // always assumes that the third argument is a node to which we have a
2470 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2471 sort_first_hop_channels(first_channels, &used_liquidities,
2472 recommended_value_msat, our_node_pubkey);
2473 for details in first_channels {
2474 let first_hop_candidate = CandidateRouteHop::FirstHop {
2475 details, payer_node_id: &our_node_id,
2477 add_entry!(&first_hop_candidate,
2478 aggregate_next_hops_fee_msat,
2479 aggregate_path_contribution_msat,
2480 aggregate_next_hops_path_htlc_minimum_msat,
2481 aggregate_next_hops_path_penalty_msat,
2482 aggregate_next_hops_cltv_delta,
2483 aggregate_next_hops_path_length);
2491 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2493 // At this point, targets are filled with the data from first and
2494 // last hops communicated by the caller, and the payment receiver.
2495 let mut found_new_path = false;
2498 // If this loop terminates due the exhaustion of targets, two situations are possible:
2499 // - not enough outgoing liquidity:
2500 // 0 < already_collected_value_msat < final_value_msat
2501 // - enough outgoing liquidity:
2502 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2503 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2504 // paths_collection will be stopped because found_new_path==false.
2505 // This is not necessarily a routing failure.
2506 '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() {
2508 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2509 // traversing the graph and arrange the path out of what we found.
2510 if node_id == our_node_id {
2511 let mut new_entry = dist.remove(&our_node_id).unwrap();
2512 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2515 let mut features_set = false;
2516 let target = ordered_hops.last().unwrap().0.candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2517 if let Some(first_channels) = first_hop_targets.get(&target) {
2518 for details in first_channels {
2519 if let CandidateRouteHop::FirstHop { details: last_hop_details, .. }
2520 = ordered_hops.last().unwrap().0.candidate
2522 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2523 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2524 features_set = true;
2531 if let Some(node) = network_nodes.get(&target) {
2532 if let Some(node_info) = node.announcement_info.as_ref() {
2533 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2535 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2538 // We can fill in features for everything except hops which were
2539 // provided via the invoice we're paying. We could guess based on the
2540 // recipient's features but for now we simply avoid guessing at all.
2544 // Means we succesfully traversed from the payer to the payee, now
2545 // save this path for the payment route. Also, update the liquidity
2546 // remaining on the used hops, so that we take them into account
2547 // while looking for more paths.
2548 if target == maybe_dummy_payee_node_id {
2552 new_entry = match dist.remove(&target) {
2553 Some(payment_hop) => payment_hop,
2554 // We can't arrive at None because, if we ever add an entry to targets,
2555 // we also fill in the entry in dist (see add_entry!).
2556 None => unreachable!(),
2558 // We "propagate" the fees one hop backward (topologically) here,
2559 // so that fees paid for a HTLC forwarding on the current channel are
2560 // associated with the previous channel (where they will be subtracted).
2561 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2562 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2564 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2565 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2567 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2568 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2570 let mut payment_path = PaymentPath {hops: ordered_hops};
2572 // We could have possibly constructed a slightly inconsistent path: since we reduce
2573 // value being transferred along the way, we could have violated htlc_minimum_msat
2574 // on some channels we already passed (assuming dest->source direction). Here, we
2575 // recompute the fees again, so that if that's the case, we match the currently
2576 // underpaid htlc_minimum_msat with fees.
2577 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2578 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2579 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2581 // Since a path allows to transfer as much value as
2582 // the smallest channel it has ("bottleneck"), we should recompute
2583 // the fees so sender HTLC don't overpay fees when traversing
2584 // larger channels than the bottleneck. This may happen because
2585 // when we were selecting those channels we were not aware how much value
2586 // this path will transfer, and the relative fee for them
2587 // might have been computed considering a larger value.
2588 // Remember that we used these channels so that we don't rely
2589 // on the same liquidity in future paths.
2590 let mut prevented_redundant_path_selection = false;
2591 for (hop, _) in payment_path.hops.iter() {
2592 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2593 let used_liquidity_msat = used_liquidities
2594 .entry(hop.candidate.id())
2595 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2596 .or_insert(spent_on_hop_msat);
2597 let hop_capacity = hop.candidate.effective_capacity();
2598 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2599 if *used_liquidity_msat == hop_max_msat {
2600 // If this path used all of this channel's available liquidity, we know
2601 // this path will not be selected again in the next loop iteration.
2602 prevented_redundant_path_selection = true;
2604 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2606 if !prevented_redundant_path_selection {
2607 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2608 // we'll probably end up picking the same path again on the next iteration.
2609 // Decrease the available liquidity of a hop in the middle of the path.
2610 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2611 let exhausted = u64::max_value();
2613 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2614 LoggedCandidateHop(victim_candidate));
2615 if let Some(scid) = victim_candidate.short_channel_id() {
2616 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2617 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2621 // Track the total amount all our collected paths allow to send so that we know
2622 // when to stop looking for more paths
2623 already_collected_value_msat += value_contribution_msat;
2625 payment_paths.push(payment_path);
2626 found_new_path = true;
2627 break 'path_construction;
2630 // If we found a path back to the payee, we shouldn't try to process it again. This is
2631 // the equivalent of the `elem.was_processed` check in
2632 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2633 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2635 // Otherwise, since the current target node is not us,
2636 // keep "unrolling" the payment graph from payee to payer by
2637 // finding a way to reach the current target from the payer side.
2638 match network_nodes.get(&node_id) {
2641 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2642 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2643 total_cltv_delta, path_length_to_node);
2649 if !found_new_path && channel_saturation_pow_half != 0 {
2650 channel_saturation_pow_half = 0;
2651 continue 'paths_collection;
2653 // If we don't support MPP, no use trying to gather more value ever.
2654 break 'paths_collection;
2658 // Stop either when the recommended value is reached or if no new path was found in this
2660 // In the latter case, making another path finding attempt won't help,
2661 // because we deterministically terminated the search due to low liquidity.
2662 if !found_new_path && channel_saturation_pow_half != 0 {
2663 channel_saturation_pow_half = 0;
2664 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2665 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2666 path_value_msat = recommended_value_msat;
2667 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2668 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2669 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2670 break 'paths_collection;
2671 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2672 // Further, if this was our first walk of the graph, and we weren't limited by an
2673 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2674 // limited by an htlc_minimum_msat value, find another path with a higher value,
2675 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2676 // still keeping a lower total fee than this path.
2677 if !hit_minimum_limit {
2678 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2679 break 'paths_collection;
2681 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.");
2682 path_value_msat = recommended_value_msat;
2686 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2687 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2688 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2689 num_ignored_total_fee_limit;
2690 if num_ignored_total > 0 {
2692 "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.",
2693 num_ignored_value_contribution, num_ignored_path_length_limit,
2694 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2695 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2696 num_ignored_total_fee_limit, num_ignored_total);
2700 if payment_paths.len() == 0 {
2701 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2704 if already_collected_value_msat < final_value_msat {
2705 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2709 let mut selected_route = payment_paths;
2711 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2712 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2714 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2715 // the value they contribute towards the payment amount.
2716 // We sort in descending order as we will remove from the front in `retain`, next.
2717 selected_route.sort_unstable_by(|a, b|
2718 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2719 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2722 // We should make sure that at least 1 path left.
2723 let mut paths_left = selected_route.len();
2724 selected_route.retain(|path| {
2725 if paths_left == 1 {
2728 let path_value_msat = path.get_value_msat();
2729 if path_value_msat <= overpaid_value_msat {
2730 overpaid_value_msat -= path_value_msat;
2736 debug_assert!(selected_route.len() > 0);
2738 if overpaid_value_msat != 0 {
2740 // Now, subtract the remaining overpaid value from the most-expensive path.
2741 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2742 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2743 selected_route.sort_unstable_by(|a, b| {
2744 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2745 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2746 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2748 let expensive_payment_path = selected_route.first_mut().unwrap();
2750 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2751 // can't go negative.
2752 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2753 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2757 // Sort by the path itself and combine redundant paths.
2758 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2759 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2761 selected_route.sort_unstable_by_key(|path| {
2762 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2763 debug_assert!(path.hops.len() <= key.len());
2764 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
2769 for idx in 0..(selected_route.len() - 1) {
2770 if idx + 1 >= selected_route.len() { break; }
2771 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
2772 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
2773 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2774 selected_route[idx].update_value_and_recompute_fees(new_value);
2775 selected_route.remove(idx + 1);
2779 let mut paths = Vec::new();
2780 for payment_path in selected_route {
2781 let mut hops = Vec::with_capacity(payment_path.hops.len());
2782 for (hop, node_features) in payment_path.hops.iter()
2783 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2785 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
2786 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2787 // If we sourced the hop from the graph we're sure the target node is announced.
2789 } else if let CandidateRouteHop::FirstHop { details, .. } = hop.candidate {
2790 // If this is a first hop we also know if it's announced.
2793 // If we sourced it any other way, we double-check the network graph to see if
2794 // there are announced channels between the endpoints. If so, the hop might be
2795 // referring to any of the announced channels, as its `short_channel_id` might be
2796 // an alias, in which case we don't take any chances here.
2797 network_graph.node(&target).map_or(false, |hop_node|
2798 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2799 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
2803 hops.push(RouteHop {
2804 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2805 node_features: node_features.clone(),
2806 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2807 channel_features: hop.candidate.features(),
2808 fee_msat: hop.fee_msat,
2809 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2810 maybe_announced_channel,
2813 let mut final_cltv_delta = final_cltv_expiry_delta;
2814 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2815 if let Some(blinded_path) = h.candidate.blinded_path() {
2816 final_cltv_delta = h.candidate.cltv_expiry_delta();
2818 hops: blinded_path.blinded_hops.clone(),
2819 blinding_point: blinded_path.blinding_point,
2820 excess_final_cltv_expiry_delta: 0,
2821 final_value_msat: h.fee_msat,
2825 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2826 // applicable for the previous hop.
2827 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2828 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2831 paths.push(Path { hops, blinded_tail });
2833 // Make sure we would never create a route with more paths than we allow.
2834 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2836 if let Some(node_features) = payment_params.payee.node_features() {
2837 for path in paths.iter_mut() {
2838 path.hops.last_mut().unwrap().node_features = node_features.clone();
2842 let route = Route { paths, route_params: Some(route_params.clone()) };
2844 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2845 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2846 if route.get_total_fees() > max_total_routing_fee_msat {
2847 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2848 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2852 log_info!(logger, "Got route: {}", log_route!(route));
2856 // When an adversarial intermediary node observes a payment, it may be able to infer its
2857 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2858 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2859 // payment path by adding a randomized 'shadow route' offset to the final hop.
2860 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2861 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2863 let network_channels = network_graph.channels();
2864 let network_nodes = network_graph.nodes();
2866 for path in route.paths.iter_mut() {
2867 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2869 // Remember the last three nodes of the random walk and avoid looping back on them.
2870 // Init with the last three nodes from the actual path, if possible.
2871 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2872 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2873 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2875 // Choose the last publicly known node as the starting point for the random walk.
2876 let mut cur_hop: Option<NodeId> = None;
2877 let mut path_nonce = [0u8; 12];
2878 if let Some(starting_hop) = path.hops.iter().rev()
2879 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2880 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2881 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2884 // Init PRNG with the path-dependant nonce, which is static for private paths.
2885 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2886 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2888 // Pick a random path length in [1 .. 3]
2889 prng.process_in_place(&mut random_path_bytes);
2890 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2892 for random_hop in 0..random_walk_length {
2893 // If we don't find a suitable offset in the public network graph, we default to
2894 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2895 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2897 if let Some(cur_node_id) = cur_hop {
2898 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2899 // Randomly choose the next unvisited hop.
2900 prng.process_in_place(&mut random_path_bytes);
2901 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2902 .checked_rem(cur_node.channels.len())
2903 .and_then(|index| cur_node.channels.get(index))
2904 .and_then(|id| network_channels.get(id)) {
2905 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2906 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2907 nodes_to_avoid[random_hop] = *next_id;
2908 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2909 cur_hop = Some(*next_id);
2916 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2917 .checked_add(random_hop_offset)
2918 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2921 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2922 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2923 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2925 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2926 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2927 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2928 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2929 max_path_offset = cmp::max(
2930 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2931 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2932 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2934 // Add 'shadow' CLTV offset to the final hop
2935 if let Some(tail) = path.blinded_tail.as_mut() {
2936 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2937 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2939 if let Some(last_hop) = path.hops.last_mut() {
2940 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2941 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2946 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2947 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2949 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2950 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2951 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2952 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2953 ) -> Result<Route, LightningError>
2954 where L::Target: Logger, GL::Target: Logger {
2955 let graph_lock = network_graph.read_only();
2956 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2957 &graph_lock, logger, random_seed_bytes)?;
2958 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2962 fn build_route_from_hops_internal<L: Deref>(
2963 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2964 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2965 ) -> Result<Route, LightningError> where L::Target: Logger {
2968 our_node_id: NodeId,
2969 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2972 impl ScoreLookUp for HopScorer {
2973 type ScoreParams = ();
2974 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
2975 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2977 let mut cur_id = self.our_node_id;
2978 for i in 0..self.hop_ids.len() {
2979 if let Some(next_id) = self.hop_ids[i] {
2980 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
2992 impl<'a> Writeable for HopScorer {
2994 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2999 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
3000 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
3003 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
3004 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
3005 for i in 0..hops.len() {
3006 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
3009 let scorer = HopScorer { our_node_id, hop_ids };
3011 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
3016 use crate::blinded_path::{BlindedHop, BlindedPath};
3017 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
3018 use crate::routing::utxo::UtxoResult;
3019 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
3020 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3021 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop};
3022 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3023 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3024 use crate::chain::transaction::OutPoint;
3025 use crate::sign::EntropySource;
3026 use crate::ln::ChannelId;
3027 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3028 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3029 use crate::ln::channelmanager;
3030 use crate::offers::invoice::BlindedPayInfo;
3031 use crate::util::config::UserConfig;
3032 use crate::util::test_utils as ln_test_utils;
3033 use crate::util::chacha20::ChaCha20;
3034 use crate::util::ser::{Readable, Writeable};
3036 use crate::util::ser::Writer;
3038 use bitcoin::hashes::Hash;
3039 use bitcoin::network::constants::Network;
3040 use bitcoin::blockdata::constants::ChainHash;
3041 use bitcoin::blockdata::script::Builder;
3042 use bitcoin::blockdata::opcodes;
3043 use bitcoin::blockdata::transaction::TxOut;
3044 use bitcoin::hashes::hex::FromHex;
3045 use bitcoin::secp256k1::{PublicKey,SecretKey};
3046 use bitcoin::secp256k1::Secp256k1;
3048 use crate::io::Cursor;
3049 use crate::prelude::*;
3050 use crate::sync::Arc;
3052 use core::convert::TryInto;
3054 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3055 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
3056 channelmanager::ChannelDetails {
3057 channel_id: ChannelId::new_zero(),
3058 counterparty: channelmanager::ChannelCounterparty {
3061 unspendable_punishment_reserve: 0,
3062 forwarding_info: None,
3063 outbound_htlc_minimum_msat: None,
3064 outbound_htlc_maximum_msat: None,
3066 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3069 outbound_scid_alias: None,
3070 inbound_scid_alias: None,
3071 channel_value_satoshis: 0,
3074 outbound_capacity_msat,
3075 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3076 next_outbound_htlc_minimum_msat: 0,
3077 inbound_capacity_msat: 42,
3078 unspendable_punishment_reserve: None,
3079 confirmations_required: None,
3080 confirmations: None,
3081 force_close_spend_delay: None,
3082 is_outbound: true, is_channel_ready: true,
3083 is_usable: true, is_public: true,
3084 inbound_htlc_minimum_msat: None,
3085 inbound_htlc_maximum_msat: None,
3087 feerate_sat_per_1000_weight: None,
3088 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
3093 fn simple_route_test() {
3094 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3095 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3096 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3097 let scorer = ln_test_utils::TestScorer::new();
3098 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3099 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3101 // Simple route to 2 via 1
3103 let route_params = RouteParameters::from_payment_params_and_value(
3104 payment_params.clone(), 0);
3105 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3106 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3107 &Default::default(), &random_seed_bytes) {
3108 assert_eq!(err, "Cannot send a payment of 0 msat");
3109 } else { panic!(); }
3111 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3112 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3113 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3114 assert_eq!(route.paths[0].hops.len(), 2);
3116 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3117 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3118 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3119 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3120 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3121 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3123 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3124 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3125 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3126 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3127 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3128 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3132 fn invalid_first_hop_test() {
3133 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3134 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3135 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3136 let scorer = ln_test_utils::TestScorer::new();
3137 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3138 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3140 // Simple route to 2 via 1
3142 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3144 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3145 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3146 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3147 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3148 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3149 } else { panic!(); }
3151 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3152 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3153 assert_eq!(route.paths[0].hops.len(), 2);
3157 fn htlc_minimum_test() {
3158 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3159 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3160 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3161 let scorer = ln_test_utils::TestScorer::new();
3162 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3163 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3165 // Simple route to 2 via 1
3167 // Disable other paths
3168 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3169 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3170 short_channel_id: 12,
3172 flags: 2, // to disable
3173 cltv_expiry_delta: 0,
3174 htlc_minimum_msat: 0,
3175 htlc_maximum_msat: MAX_VALUE_MSAT,
3177 fee_proportional_millionths: 0,
3178 excess_data: Vec::new()
3180 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3181 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3182 short_channel_id: 3,
3184 flags: 2, // to disable
3185 cltv_expiry_delta: 0,
3186 htlc_minimum_msat: 0,
3187 htlc_maximum_msat: MAX_VALUE_MSAT,
3189 fee_proportional_millionths: 0,
3190 excess_data: Vec::new()
3192 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3193 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3194 short_channel_id: 13,
3196 flags: 2, // to disable
3197 cltv_expiry_delta: 0,
3198 htlc_minimum_msat: 0,
3199 htlc_maximum_msat: MAX_VALUE_MSAT,
3201 fee_proportional_millionths: 0,
3202 excess_data: Vec::new()
3204 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3205 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3206 short_channel_id: 6,
3208 flags: 2, // to disable
3209 cltv_expiry_delta: 0,
3210 htlc_minimum_msat: 0,
3211 htlc_maximum_msat: MAX_VALUE_MSAT,
3213 fee_proportional_millionths: 0,
3214 excess_data: Vec::new()
3216 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3217 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3218 short_channel_id: 7,
3220 flags: 2, // to disable
3221 cltv_expiry_delta: 0,
3222 htlc_minimum_msat: 0,
3223 htlc_maximum_msat: MAX_VALUE_MSAT,
3225 fee_proportional_millionths: 0,
3226 excess_data: Vec::new()
3229 // Check against amount_to_transfer_over_msat.
3230 // Set minimal HTLC of 200_000_000 msat.
3231 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3232 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3233 short_channel_id: 2,
3236 cltv_expiry_delta: 0,
3237 htlc_minimum_msat: 200_000_000,
3238 htlc_maximum_msat: MAX_VALUE_MSAT,
3240 fee_proportional_millionths: 0,
3241 excess_data: Vec::new()
3244 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3246 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3247 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3248 short_channel_id: 4,
3251 cltv_expiry_delta: 0,
3252 htlc_minimum_msat: 0,
3253 htlc_maximum_msat: 199_999_999,
3255 fee_proportional_millionths: 0,
3256 excess_data: Vec::new()
3259 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3260 let route_params = RouteParameters::from_payment_params_and_value(
3261 payment_params, 199_999_999);
3262 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3263 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3264 &Default::default(), &random_seed_bytes) {
3265 assert_eq!(err, "Failed to find a path to the given destination");
3266 } else { panic!(); }
3268 // Lift the restriction on the first hop.
3269 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3270 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3271 short_channel_id: 2,
3274 cltv_expiry_delta: 0,
3275 htlc_minimum_msat: 0,
3276 htlc_maximum_msat: MAX_VALUE_MSAT,
3278 fee_proportional_millionths: 0,
3279 excess_data: Vec::new()
3282 // A payment above the minimum should pass
3283 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3284 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3285 assert_eq!(route.paths[0].hops.len(), 2);
3289 fn htlc_minimum_overpay_test() {
3290 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3291 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3292 let config = UserConfig::default();
3293 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3294 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3296 let scorer = ln_test_utils::TestScorer::new();
3297 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3298 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3300 // A route to node#2 via two paths.
3301 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3302 // Thus, they can't send 60 without overpaying.
3303 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3304 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3305 short_channel_id: 2,
3308 cltv_expiry_delta: 0,
3309 htlc_minimum_msat: 35_000,
3310 htlc_maximum_msat: 40_000,
3312 fee_proportional_millionths: 0,
3313 excess_data: Vec::new()
3315 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3316 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3317 short_channel_id: 12,
3320 cltv_expiry_delta: 0,
3321 htlc_minimum_msat: 35_000,
3322 htlc_maximum_msat: 40_000,
3324 fee_proportional_millionths: 0,
3325 excess_data: Vec::new()
3329 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3330 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3331 short_channel_id: 13,
3334 cltv_expiry_delta: 0,
3335 htlc_minimum_msat: 0,
3336 htlc_maximum_msat: MAX_VALUE_MSAT,
3338 fee_proportional_millionths: 0,
3339 excess_data: Vec::new()
3341 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3342 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3343 short_channel_id: 4,
3346 cltv_expiry_delta: 0,
3347 htlc_minimum_msat: 0,
3348 htlc_maximum_msat: MAX_VALUE_MSAT,
3350 fee_proportional_millionths: 0,
3351 excess_data: Vec::new()
3354 // Disable other paths
3355 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3356 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3357 short_channel_id: 1,
3359 flags: 2, // to disable
3360 cltv_expiry_delta: 0,
3361 htlc_minimum_msat: 0,
3362 htlc_maximum_msat: MAX_VALUE_MSAT,
3364 fee_proportional_millionths: 0,
3365 excess_data: Vec::new()
3368 let mut route_params = RouteParameters::from_payment_params_and_value(
3369 payment_params.clone(), 60_000);
3370 route_params.max_total_routing_fee_msat = Some(15_000);
3371 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3372 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3373 // Overpay fees to hit htlc_minimum_msat.
3374 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3375 // TODO: this could be better balanced to overpay 10k and not 15k.
3376 assert_eq!(overpaid_fees, 15_000);
3378 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3379 // while taking even more fee to match htlc_minimum_msat.
3380 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3381 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3382 short_channel_id: 12,
3385 cltv_expiry_delta: 0,
3386 htlc_minimum_msat: 65_000,
3387 htlc_maximum_msat: 80_000,
3389 fee_proportional_millionths: 0,
3390 excess_data: Vec::new()
3392 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3393 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3394 short_channel_id: 2,
3397 cltv_expiry_delta: 0,
3398 htlc_minimum_msat: 0,
3399 htlc_maximum_msat: MAX_VALUE_MSAT,
3401 fee_proportional_millionths: 0,
3402 excess_data: Vec::new()
3404 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3405 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3406 short_channel_id: 4,
3409 cltv_expiry_delta: 0,
3410 htlc_minimum_msat: 0,
3411 htlc_maximum_msat: MAX_VALUE_MSAT,
3413 fee_proportional_millionths: 100_000,
3414 excess_data: Vec::new()
3417 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3418 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3419 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3420 assert_eq!(route.paths.len(), 1);
3421 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3422 let fees = route.paths[0].hops[0].fee_msat;
3423 assert_eq!(fees, 5_000);
3425 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3426 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3427 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3428 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3429 // the other channel.
3430 assert_eq!(route.paths.len(), 1);
3431 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3432 let fees = route.paths[0].hops[0].fee_msat;
3433 assert_eq!(fees, 5_000);
3437 fn htlc_minimum_recipient_overpay_test() {
3438 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3439 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3440 let config = UserConfig::default();
3441 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3442 let scorer = ln_test_utils::TestScorer::new();
3443 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3444 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3446 // Route to node2 over a single path which requires overpaying the recipient themselves.
3448 // First disable all paths except the us -> node1 -> node2 path
3449 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3450 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3451 short_channel_id: 13,
3454 cltv_expiry_delta: 0,
3455 htlc_minimum_msat: 0,
3456 htlc_maximum_msat: 0,
3458 fee_proportional_millionths: 0,
3459 excess_data: Vec::new()
3462 // Set channel 4 to free but with a high htlc_minimum_msat
3463 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3464 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3465 short_channel_id: 4,
3468 cltv_expiry_delta: 0,
3469 htlc_minimum_msat: 15_000,
3470 htlc_maximum_msat: MAX_VALUE_MSAT,
3472 fee_proportional_millionths: 0,
3473 excess_data: Vec::new()
3476 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3477 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3478 // what we try to find a route for, so this test only just happens to work out to exactly
3480 let mut route_params = RouteParameters::from_payment_params_and_value(
3481 payment_params.clone(), 5_000);
3482 route_params.max_total_routing_fee_msat = Some(9_999);
3483 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3484 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3485 &Default::default(), &random_seed_bytes) {
3486 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3487 } else { panic!(); }
3489 let mut route_params = RouteParameters::from_payment_params_and_value(
3490 payment_params.clone(), 5_000);
3491 route_params.max_total_routing_fee_msat = Some(10_000);
3492 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3493 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3494 assert_eq!(route.get_total_fees(), 10_000);
3498 fn disable_channels_test() {
3499 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3500 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3501 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3502 let scorer = ln_test_utils::TestScorer::new();
3503 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3504 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3506 // // Disable channels 4 and 12 by flags=2
3507 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3508 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3509 short_channel_id: 4,
3511 flags: 2, // to disable
3512 cltv_expiry_delta: 0,
3513 htlc_minimum_msat: 0,
3514 htlc_maximum_msat: MAX_VALUE_MSAT,
3516 fee_proportional_millionths: 0,
3517 excess_data: Vec::new()
3519 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3520 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3521 short_channel_id: 12,
3523 flags: 2, // to disable
3524 cltv_expiry_delta: 0,
3525 htlc_minimum_msat: 0,
3526 htlc_maximum_msat: MAX_VALUE_MSAT,
3528 fee_proportional_millionths: 0,
3529 excess_data: Vec::new()
3532 // If all the channels require some features we don't understand, route should fail
3533 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3534 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3535 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3536 &Default::default(), &random_seed_bytes) {
3537 assert_eq!(err, "Failed to find a path to the given destination");
3538 } else { panic!(); }
3540 // If we specify a channel to node7, that overrides our local channel view and that gets used
3541 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3542 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3543 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3544 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3545 &Default::default(), &random_seed_bytes).unwrap();
3546 assert_eq!(route.paths[0].hops.len(), 2);
3548 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3549 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3550 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3551 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3552 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3553 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3555 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3556 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3557 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3558 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3559 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3560 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3564 fn disable_node_test() {
3565 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3566 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3567 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3568 let scorer = ln_test_utils::TestScorer::new();
3569 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3570 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3572 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3573 let mut unknown_features = NodeFeatures::empty();
3574 unknown_features.set_unknown_feature_required();
3575 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3576 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3577 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3579 // If all nodes require some features we don't understand, route should fail
3580 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3581 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3582 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3583 &Default::default(), &random_seed_bytes) {
3584 assert_eq!(err, "Failed to find a path to the given destination");
3585 } else { panic!(); }
3587 // If we specify a channel to node7, that overrides our local channel view and that gets used
3588 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3589 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3590 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3591 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3592 &Default::default(), &random_seed_bytes).unwrap();
3593 assert_eq!(route.paths[0].hops.len(), 2);
3595 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3596 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3597 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3598 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3599 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3600 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3602 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3603 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3604 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3605 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3606 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3607 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3609 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3610 // naively) assume that the user checked the feature bits on the invoice, which override
3611 // the node_announcement.
3615 fn our_chans_test() {
3616 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3617 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3618 let scorer = ln_test_utils::TestScorer::new();
3619 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3620 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3622 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3623 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3624 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3625 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3626 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3627 assert_eq!(route.paths[0].hops.len(), 3);
3629 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3630 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3631 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3632 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3633 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3634 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3636 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3637 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3638 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3639 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3640 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3641 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3643 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3644 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3645 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3646 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3647 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3648 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3650 // If we specify a channel to node7, that overrides our local channel view and that gets used
3651 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3652 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3653 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3654 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3655 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3656 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3657 &Default::default(), &random_seed_bytes).unwrap();
3658 assert_eq!(route.paths[0].hops.len(), 2);
3660 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3661 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3662 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3663 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3664 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3665 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3667 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3668 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3669 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3670 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3671 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3672 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3675 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3676 let zero_fees = RoutingFees {
3678 proportional_millionths: 0,
3680 vec![RouteHint(vec![RouteHintHop {
3681 src_node_id: nodes[3],
3682 short_channel_id: 8,
3684 cltv_expiry_delta: (8 << 4) | 1,
3685 htlc_minimum_msat: None,
3686 htlc_maximum_msat: None,
3688 ]), RouteHint(vec![RouteHintHop {
3689 src_node_id: nodes[4],
3690 short_channel_id: 9,
3693 proportional_millionths: 0,
3695 cltv_expiry_delta: (9 << 4) | 1,
3696 htlc_minimum_msat: None,
3697 htlc_maximum_msat: None,
3698 }]), RouteHint(vec![RouteHintHop {
3699 src_node_id: nodes[5],
3700 short_channel_id: 10,
3702 cltv_expiry_delta: (10 << 4) | 1,
3703 htlc_minimum_msat: None,
3704 htlc_maximum_msat: None,
3708 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3709 let zero_fees = RoutingFees {
3711 proportional_millionths: 0,
3713 vec![RouteHint(vec![RouteHintHop {
3714 src_node_id: nodes[2],
3715 short_channel_id: 5,
3718 proportional_millionths: 0,
3720 cltv_expiry_delta: (5 << 4) | 1,
3721 htlc_minimum_msat: None,
3722 htlc_maximum_msat: None,
3724 src_node_id: nodes[3],
3725 short_channel_id: 8,
3727 cltv_expiry_delta: (8 << 4) | 1,
3728 htlc_minimum_msat: None,
3729 htlc_maximum_msat: None,
3731 ]), RouteHint(vec![RouteHintHop {
3732 src_node_id: nodes[4],
3733 short_channel_id: 9,
3736 proportional_millionths: 0,
3738 cltv_expiry_delta: (9 << 4) | 1,
3739 htlc_minimum_msat: None,
3740 htlc_maximum_msat: None,
3741 }]), RouteHint(vec![RouteHintHop {
3742 src_node_id: nodes[5],
3743 short_channel_id: 10,
3745 cltv_expiry_delta: (10 << 4) | 1,
3746 htlc_minimum_msat: None,
3747 htlc_maximum_msat: None,
3752 fn partial_route_hint_test() {
3753 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3754 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3755 let scorer = ln_test_utils::TestScorer::new();
3756 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3757 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3759 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3760 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3761 // RouteHint may be partially used by the algo to build the best path.
3763 // First check that last hop can't have its source as the payee.
3764 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3765 src_node_id: nodes[6],
3766 short_channel_id: 8,
3769 proportional_millionths: 0,
3771 cltv_expiry_delta: (8 << 4) | 1,
3772 htlc_minimum_msat: None,
3773 htlc_maximum_msat: None,
3776 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3777 invalid_last_hops.push(invalid_last_hop);
3779 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3780 .with_route_hints(invalid_last_hops).unwrap();
3781 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3782 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3783 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3784 &Default::default(), &random_seed_bytes) {
3785 assert_eq!(err, "Route hint cannot have the payee as the source.");
3786 } else { panic!(); }
3789 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3790 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3791 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3792 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3793 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3794 assert_eq!(route.paths[0].hops.len(), 5);
3796 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3797 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3798 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3799 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3800 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3801 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3803 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3804 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3805 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3806 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3807 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3808 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3810 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3811 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3812 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3813 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3814 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3815 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3817 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3818 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3819 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3820 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3821 // If we have a peer in the node map, we'll use their features here since we don't have
3822 // a way of figuring out their features from the invoice:
3823 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3824 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3826 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3827 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3828 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3829 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3830 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3831 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3834 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3835 let zero_fees = RoutingFees {
3837 proportional_millionths: 0,
3839 vec![RouteHint(vec![RouteHintHop {
3840 src_node_id: nodes[3],
3841 short_channel_id: 8,
3843 cltv_expiry_delta: (8 << 4) | 1,
3844 htlc_minimum_msat: None,
3845 htlc_maximum_msat: None,
3846 }]), RouteHint(vec![
3848 ]), RouteHint(vec![RouteHintHop {
3849 src_node_id: nodes[5],
3850 short_channel_id: 10,
3852 cltv_expiry_delta: (10 << 4) | 1,
3853 htlc_minimum_msat: None,
3854 htlc_maximum_msat: None,
3859 fn ignores_empty_last_hops_test() {
3860 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3861 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3862 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3863 let scorer = ln_test_utils::TestScorer::new();
3864 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3865 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3867 // Test handling of an empty RouteHint passed in Invoice.
3868 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3869 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3870 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3871 assert_eq!(route.paths[0].hops.len(), 5);
3873 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3874 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3875 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3876 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3877 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3878 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3880 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3881 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3882 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3883 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3884 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3885 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3887 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3888 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3889 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3890 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3891 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3892 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3894 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3895 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3896 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3897 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3898 // If we have a peer in the node map, we'll use their features here since we don't have
3899 // a way of figuring out their features from the invoice:
3900 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3901 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3903 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3904 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3905 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3906 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3907 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3908 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3911 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3913 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3914 let zero_fees = RoutingFees {
3916 proportional_millionths: 0,
3918 vec![RouteHint(vec![RouteHintHop {
3919 src_node_id: hint_hops[0],
3920 short_channel_id: 0xff00,
3923 proportional_millionths: 0,
3925 cltv_expiry_delta: (5 << 4) | 1,
3926 htlc_minimum_msat: None,
3927 htlc_maximum_msat: None,
3929 src_node_id: hint_hops[1],
3930 short_channel_id: 0xff01,
3932 cltv_expiry_delta: (8 << 4) | 1,
3933 htlc_minimum_msat: None,
3934 htlc_maximum_msat: None,
3939 fn multi_hint_last_hops_test() {
3940 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3941 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3942 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3943 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3944 let scorer = ln_test_utils::TestScorer::new();
3945 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3946 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3947 // Test through channels 2, 3, 0xff00, 0xff01.
3948 // Test shows that multiple hop hints are considered.
3950 // Disabling channels 6 & 7 by flags=2
3951 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3952 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3953 short_channel_id: 6,
3955 flags: 2, // to disable
3956 cltv_expiry_delta: 0,
3957 htlc_minimum_msat: 0,
3958 htlc_maximum_msat: MAX_VALUE_MSAT,
3960 fee_proportional_millionths: 0,
3961 excess_data: Vec::new()
3963 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3964 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3965 short_channel_id: 7,
3967 flags: 2, // to disable
3968 cltv_expiry_delta: 0,
3969 htlc_minimum_msat: 0,
3970 htlc_maximum_msat: MAX_VALUE_MSAT,
3972 fee_proportional_millionths: 0,
3973 excess_data: Vec::new()
3976 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3977 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3978 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3979 assert_eq!(route.paths[0].hops.len(), 4);
3981 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3982 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3983 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3984 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3985 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3986 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3988 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3989 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3990 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3991 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3992 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3993 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3995 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3996 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3997 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3998 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3999 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
4000 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4002 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4003 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4004 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4005 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4006 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4007 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4011 fn private_multi_hint_last_hops_test() {
4012 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4013 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4015 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
4016 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
4018 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
4019 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4020 let scorer = ln_test_utils::TestScorer::new();
4021 // Test through channels 2, 3, 0xff00, 0xff01.
4022 // Test shows that multiple hop hints are considered.
4024 // Disabling channels 6 & 7 by flags=2
4025 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4026 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4027 short_channel_id: 6,
4029 flags: 2, // to disable
4030 cltv_expiry_delta: 0,
4031 htlc_minimum_msat: 0,
4032 htlc_maximum_msat: MAX_VALUE_MSAT,
4034 fee_proportional_millionths: 0,
4035 excess_data: Vec::new()
4037 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4038 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4039 short_channel_id: 7,
4041 flags: 2, // to disable
4042 cltv_expiry_delta: 0,
4043 htlc_minimum_msat: 0,
4044 htlc_maximum_msat: MAX_VALUE_MSAT,
4046 fee_proportional_millionths: 0,
4047 excess_data: Vec::new()
4050 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4051 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4052 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4053 assert_eq!(route.paths[0].hops.len(), 4);
4055 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4056 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4057 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4058 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4059 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4060 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4062 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4063 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4064 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4065 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4066 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4067 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4069 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4070 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4071 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4072 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4073 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4074 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4076 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4077 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4078 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4079 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4080 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4081 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4084 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4085 let zero_fees = RoutingFees {
4087 proportional_millionths: 0,
4089 vec![RouteHint(vec![RouteHintHop {
4090 src_node_id: nodes[4],
4091 short_channel_id: 11,
4093 cltv_expiry_delta: (11 << 4) | 1,
4094 htlc_minimum_msat: None,
4095 htlc_maximum_msat: None,
4097 src_node_id: nodes[3],
4098 short_channel_id: 8,
4100 cltv_expiry_delta: (8 << 4) | 1,
4101 htlc_minimum_msat: None,
4102 htlc_maximum_msat: None,
4103 }]), RouteHint(vec![RouteHintHop {
4104 src_node_id: nodes[4],
4105 short_channel_id: 9,
4108 proportional_millionths: 0,
4110 cltv_expiry_delta: (9 << 4) | 1,
4111 htlc_minimum_msat: None,
4112 htlc_maximum_msat: None,
4113 }]), RouteHint(vec![RouteHintHop {
4114 src_node_id: nodes[5],
4115 short_channel_id: 10,
4117 cltv_expiry_delta: (10 << 4) | 1,
4118 htlc_minimum_msat: None,
4119 htlc_maximum_msat: None,
4124 fn last_hops_with_public_channel_test() {
4125 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4126 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4127 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4128 let scorer = ln_test_utils::TestScorer::new();
4129 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4130 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4131 // This test shows that public routes can be present in the invoice
4132 // which would be handled in the same manner.
4134 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4135 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4136 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4137 assert_eq!(route.paths[0].hops.len(), 5);
4139 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4140 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4141 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4142 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4143 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4144 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4146 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4147 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4148 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4149 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4150 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4151 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4153 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4154 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4155 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4156 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4157 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4158 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4160 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4161 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4162 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4163 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4164 // If we have a peer in the node map, we'll use their features here since we don't have
4165 // a way of figuring out their features from the invoice:
4166 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4167 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4169 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4170 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4171 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4172 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4173 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4174 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4178 fn our_chans_last_hop_connect_test() {
4179 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4180 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4181 let scorer = ln_test_utils::TestScorer::new();
4182 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4183 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4185 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4186 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4187 let mut last_hops = last_hops(&nodes);
4188 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4189 .with_route_hints(last_hops.clone()).unwrap();
4190 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4191 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4192 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4193 &Default::default(), &random_seed_bytes).unwrap();
4194 assert_eq!(route.paths[0].hops.len(), 2);
4196 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4197 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4198 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4199 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4200 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4201 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4203 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4204 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4205 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4206 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4207 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4208 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4210 last_hops[0].0[0].fees.base_msat = 1000;
4212 // Revert to via 6 as the fee on 8 goes up
4213 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4214 .with_route_hints(last_hops).unwrap();
4215 let route_params = RouteParameters::from_payment_params_and_value(
4216 payment_params.clone(), 100);
4217 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4218 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4219 assert_eq!(route.paths[0].hops.len(), 4);
4221 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4222 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4223 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4224 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4225 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4226 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4228 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4229 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4230 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4231 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4232 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4233 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4235 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4236 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4237 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4238 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4239 // If we have a peer in the node map, we'll use their features here since we don't have
4240 // a way of figuring out their features from the invoice:
4241 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4242 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4244 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4245 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4246 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4247 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4248 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4249 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4251 // ...but still use 8 for larger payments as 6 has a variable feerate
4252 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4253 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4254 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4255 assert_eq!(route.paths[0].hops.len(), 5);
4257 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4258 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4259 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4260 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4261 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4262 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4264 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4265 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4266 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4267 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4268 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4269 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4271 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4272 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4273 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4274 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4275 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4276 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4278 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4279 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4280 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4281 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4282 // If we have a peer in the node map, we'll use their features here since we don't have
4283 // a way of figuring out their features from the invoice:
4284 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4285 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4287 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4288 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4289 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4290 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4291 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4292 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4295 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> {
4296 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4297 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4298 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4300 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4301 let last_hops = RouteHint(vec![RouteHintHop {
4302 src_node_id: middle_node_id,
4303 short_channel_id: 8,
4306 proportional_millionths: last_hop_fee_prop,
4308 cltv_expiry_delta: (8 << 4) | 1,
4309 htlc_minimum_msat: None,
4310 htlc_maximum_msat: last_hop_htlc_max,
4312 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4313 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4314 let scorer = ln_test_utils::TestScorer::new();
4315 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4316 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4317 let logger = ln_test_utils::TestLogger::new();
4318 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4319 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4320 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4321 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4322 &random_seed_bytes);
4327 fn unannounced_path_test() {
4328 // We should be able to send a payment to a destination without any help of a routing graph
4329 // if we have a channel with a common counterparty that appears in the first and last hop
4331 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4333 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4334 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4335 assert_eq!(route.paths[0].hops.len(), 2);
4337 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4338 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4339 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4340 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4341 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4342 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4344 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4345 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4346 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4347 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4348 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4349 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4353 fn overflow_unannounced_path_test_liquidity_underflow() {
4354 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4355 // the last-hop had a fee which overflowed a u64, we'd panic.
4356 // This was due to us adding the first-hop from us unconditionally, causing us to think
4357 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4358 // In this test, we previously hit a subtraction underflow due to having less available
4359 // liquidity at the last hop than 0.
4360 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());
4364 fn overflow_unannounced_path_test_feerate_overflow() {
4365 // This tests for the same case as above, except instead of hitting a subtraction
4366 // underflow, we hit a case where the fee charged at a hop overflowed.
4367 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());
4371 fn available_amount_while_routing_test() {
4372 // Tests whether we choose the correct available channel amount while routing.
4374 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4375 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4376 let scorer = ln_test_utils::TestScorer::new();
4377 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4378 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4379 let config = UserConfig::default();
4380 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4381 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4384 // We will use a simple single-path route from
4385 // our node to node2 via node0: channels {1, 3}.
4387 // First disable all other paths.
4388 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4389 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4390 short_channel_id: 2,
4393 cltv_expiry_delta: 0,
4394 htlc_minimum_msat: 0,
4395 htlc_maximum_msat: 100_000,
4397 fee_proportional_millionths: 0,
4398 excess_data: Vec::new()
4400 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4401 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4402 short_channel_id: 12,
4405 cltv_expiry_delta: 0,
4406 htlc_minimum_msat: 0,
4407 htlc_maximum_msat: 100_000,
4409 fee_proportional_millionths: 0,
4410 excess_data: Vec::new()
4413 // Make the first channel (#1) very permissive,
4414 // and we will be testing all limits on the second channel.
4415 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4416 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4417 short_channel_id: 1,
4420 cltv_expiry_delta: 0,
4421 htlc_minimum_msat: 0,
4422 htlc_maximum_msat: 1_000_000_000,
4424 fee_proportional_millionths: 0,
4425 excess_data: Vec::new()
4428 // First, let's see if routing works if we have absolutely no idea about the available amount.
4429 // In this case, it should be set to 250_000 sats.
4430 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4431 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4432 short_channel_id: 3,
4435 cltv_expiry_delta: 0,
4436 htlc_minimum_msat: 0,
4437 htlc_maximum_msat: 250_000_000,
4439 fee_proportional_millionths: 0,
4440 excess_data: Vec::new()
4444 // Attempt to route more than available results in a failure.
4445 let route_params = RouteParameters::from_payment_params_and_value(
4446 payment_params.clone(), 250_000_001);
4447 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4448 &our_id, &route_params, &network_graph.read_only(), None,
4449 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4450 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4451 } else { panic!(); }
4455 // Now, attempt to route an exact amount we have should be fine.
4456 let route_params = RouteParameters::from_payment_params_and_value(
4457 payment_params.clone(), 250_000_000);
4458 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4459 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4460 assert_eq!(route.paths.len(), 1);
4461 let path = route.paths.last().unwrap();
4462 assert_eq!(path.hops.len(), 2);
4463 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4464 assert_eq!(path.final_value_msat(), 250_000_000);
4467 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4468 // Disable channel #1 and use another first hop.
4469 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4470 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4471 short_channel_id: 1,
4474 cltv_expiry_delta: 0,
4475 htlc_minimum_msat: 0,
4476 htlc_maximum_msat: 1_000_000_000,
4478 fee_proportional_millionths: 0,
4479 excess_data: Vec::new()
4482 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4483 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4486 // Attempt to route more than available results in a failure.
4487 let route_params = RouteParameters::from_payment_params_and_value(
4488 payment_params.clone(), 200_000_001);
4489 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4490 &our_id, &route_params, &network_graph.read_only(),
4491 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4492 &Default::default(), &random_seed_bytes) {
4493 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4494 } else { panic!(); }
4498 // Now, attempt to route an exact amount we have should be fine.
4499 let route_params = RouteParameters::from_payment_params_and_value(
4500 payment_params.clone(), 200_000_000);
4501 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4502 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4503 &Default::default(), &random_seed_bytes).unwrap();
4504 assert_eq!(route.paths.len(), 1);
4505 let path = route.paths.last().unwrap();
4506 assert_eq!(path.hops.len(), 2);
4507 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4508 assert_eq!(path.final_value_msat(), 200_000_000);
4511 // Enable channel #1 back.
4512 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4513 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4514 short_channel_id: 1,
4517 cltv_expiry_delta: 0,
4518 htlc_minimum_msat: 0,
4519 htlc_maximum_msat: 1_000_000_000,
4521 fee_proportional_millionths: 0,
4522 excess_data: Vec::new()
4526 // Now let's see if routing works if we know only htlc_maximum_msat.
4527 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4528 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4529 short_channel_id: 3,
4532 cltv_expiry_delta: 0,
4533 htlc_minimum_msat: 0,
4534 htlc_maximum_msat: 15_000,
4536 fee_proportional_millionths: 0,
4537 excess_data: Vec::new()
4541 // Attempt to route more than available results in a failure.
4542 let route_params = RouteParameters::from_payment_params_and_value(
4543 payment_params.clone(), 15_001);
4544 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4545 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4546 &scorer, &Default::default(), &random_seed_bytes) {
4547 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4548 } else { panic!(); }
4552 // Now, attempt to route an exact amount we have should be fine.
4553 let route_params = RouteParameters::from_payment_params_and_value(
4554 payment_params.clone(), 15_000);
4555 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4556 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4557 assert_eq!(route.paths.len(), 1);
4558 let path = route.paths.last().unwrap();
4559 assert_eq!(path.hops.len(), 2);
4560 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4561 assert_eq!(path.final_value_msat(), 15_000);
4564 // Now let's see if routing works if we know only capacity from the UTXO.
4566 // We can't change UTXO capacity on the fly, so we'll disable
4567 // the existing channel and add another one with the capacity we need.
4568 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4569 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4570 short_channel_id: 3,
4573 cltv_expiry_delta: 0,
4574 htlc_minimum_msat: 0,
4575 htlc_maximum_msat: MAX_VALUE_MSAT,
4577 fee_proportional_millionths: 0,
4578 excess_data: Vec::new()
4581 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4582 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4583 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4584 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4585 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4587 *chain_monitor.utxo_ret.lock().unwrap() =
4588 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4589 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4591 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4592 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4593 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4594 short_channel_id: 333,
4597 cltv_expiry_delta: (3 << 4) | 1,
4598 htlc_minimum_msat: 0,
4599 htlc_maximum_msat: 15_000,
4601 fee_proportional_millionths: 0,
4602 excess_data: Vec::new()
4604 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4605 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4606 short_channel_id: 333,
4609 cltv_expiry_delta: (3 << 4) | 2,
4610 htlc_minimum_msat: 0,
4611 htlc_maximum_msat: 15_000,
4613 fee_proportional_millionths: 0,
4614 excess_data: Vec::new()
4618 // Attempt to route more than available results in a failure.
4619 let route_params = RouteParameters::from_payment_params_and_value(
4620 payment_params.clone(), 15_001);
4621 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4622 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4623 &scorer, &Default::default(), &random_seed_bytes) {
4624 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4625 } else { panic!(); }
4629 // Now, attempt to route an exact amount we have should be fine.
4630 let route_params = RouteParameters::from_payment_params_and_value(
4631 payment_params.clone(), 15_000);
4632 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4633 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4634 assert_eq!(route.paths.len(), 1);
4635 let path = route.paths.last().unwrap();
4636 assert_eq!(path.hops.len(), 2);
4637 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4638 assert_eq!(path.final_value_msat(), 15_000);
4641 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4642 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4643 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4644 short_channel_id: 333,
4647 cltv_expiry_delta: 0,
4648 htlc_minimum_msat: 0,
4649 htlc_maximum_msat: 10_000,
4651 fee_proportional_millionths: 0,
4652 excess_data: Vec::new()
4656 // Attempt to route more than available results in a failure.
4657 let route_params = RouteParameters::from_payment_params_and_value(
4658 payment_params.clone(), 10_001);
4659 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4660 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4661 &scorer, &Default::default(), &random_seed_bytes) {
4662 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4663 } else { panic!(); }
4667 // Now, attempt to route an exact amount we have should be fine.
4668 let route_params = RouteParameters::from_payment_params_and_value(
4669 payment_params.clone(), 10_000);
4670 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4671 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4672 assert_eq!(route.paths.len(), 1);
4673 let path = route.paths.last().unwrap();
4674 assert_eq!(path.hops.len(), 2);
4675 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4676 assert_eq!(path.final_value_msat(), 10_000);
4681 fn available_liquidity_last_hop_test() {
4682 // Check that available liquidity properly limits the path even when only
4683 // one of the latter hops is limited.
4684 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4685 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4686 let scorer = ln_test_utils::TestScorer::new();
4687 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4688 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4689 let config = UserConfig::default();
4690 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4691 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4694 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4695 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4696 // Total capacity: 50 sats.
4698 // Disable other potential paths.
4699 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4700 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4701 short_channel_id: 2,
4704 cltv_expiry_delta: 0,
4705 htlc_minimum_msat: 0,
4706 htlc_maximum_msat: 100_000,
4708 fee_proportional_millionths: 0,
4709 excess_data: Vec::new()
4711 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4712 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4713 short_channel_id: 7,
4716 cltv_expiry_delta: 0,
4717 htlc_minimum_msat: 0,
4718 htlc_maximum_msat: 100_000,
4720 fee_proportional_millionths: 0,
4721 excess_data: Vec::new()
4726 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4727 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4728 short_channel_id: 12,
4731 cltv_expiry_delta: 0,
4732 htlc_minimum_msat: 0,
4733 htlc_maximum_msat: 100_000,
4735 fee_proportional_millionths: 0,
4736 excess_data: Vec::new()
4738 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4739 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4740 short_channel_id: 13,
4743 cltv_expiry_delta: 0,
4744 htlc_minimum_msat: 0,
4745 htlc_maximum_msat: 100_000,
4747 fee_proportional_millionths: 0,
4748 excess_data: Vec::new()
4751 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4752 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4753 short_channel_id: 6,
4756 cltv_expiry_delta: 0,
4757 htlc_minimum_msat: 0,
4758 htlc_maximum_msat: 50_000,
4760 fee_proportional_millionths: 0,
4761 excess_data: Vec::new()
4763 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4764 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4765 short_channel_id: 11,
4768 cltv_expiry_delta: 0,
4769 htlc_minimum_msat: 0,
4770 htlc_maximum_msat: 100_000,
4772 fee_proportional_millionths: 0,
4773 excess_data: Vec::new()
4776 // Attempt to route more than available results in a failure.
4777 let route_params = RouteParameters::from_payment_params_and_value(
4778 payment_params.clone(), 60_000);
4779 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4780 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4781 &scorer, &Default::default(), &random_seed_bytes) {
4782 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4783 } else { panic!(); }
4787 // Now, attempt to route 49 sats (just a bit below the capacity).
4788 let route_params = RouteParameters::from_payment_params_and_value(
4789 payment_params.clone(), 49_000);
4790 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4791 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4792 assert_eq!(route.paths.len(), 1);
4793 let mut total_amount_paid_msat = 0;
4794 for path in &route.paths {
4795 assert_eq!(path.hops.len(), 4);
4796 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4797 total_amount_paid_msat += path.final_value_msat();
4799 assert_eq!(total_amount_paid_msat, 49_000);
4803 // Attempt to route an exact amount is also fine
4804 let route_params = RouteParameters::from_payment_params_and_value(
4805 payment_params, 50_000);
4806 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4807 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4808 assert_eq!(route.paths.len(), 1);
4809 let mut total_amount_paid_msat = 0;
4810 for path in &route.paths {
4811 assert_eq!(path.hops.len(), 4);
4812 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4813 total_amount_paid_msat += path.final_value_msat();
4815 assert_eq!(total_amount_paid_msat, 50_000);
4820 fn ignore_fee_first_hop_test() {
4821 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4822 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4823 let scorer = ln_test_utils::TestScorer::new();
4824 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4825 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4826 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4828 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4829 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4830 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4831 short_channel_id: 1,
4834 cltv_expiry_delta: 0,
4835 htlc_minimum_msat: 0,
4836 htlc_maximum_msat: 100_000,
4837 fee_base_msat: 1_000_000,
4838 fee_proportional_millionths: 0,
4839 excess_data: Vec::new()
4841 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4842 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4843 short_channel_id: 3,
4846 cltv_expiry_delta: 0,
4847 htlc_minimum_msat: 0,
4848 htlc_maximum_msat: 50_000,
4850 fee_proportional_millionths: 0,
4851 excess_data: Vec::new()
4855 let route_params = RouteParameters::from_payment_params_and_value(
4856 payment_params, 50_000);
4857 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4858 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4859 assert_eq!(route.paths.len(), 1);
4860 let mut total_amount_paid_msat = 0;
4861 for path in &route.paths {
4862 assert_eq!(path.hops.len(), 2);
4863 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4864 total_amount_paid_msat += path.final_value_msat();
4866 assert_eq!(total_amount_paid_msat, 50_000);
4871 fn simple_mpp_route_test() {
4872 let (secp_ctx, _, _, _, _) = build_graph();
4873 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4874 let config = UserConfig::default();
4875 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4876 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4878 do_simple_mpp_route_test(clear_payment_params);
4880 // MPP to a 1-hop blinded path for nodes[2]
4881 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
4882 let blinded_path = BlindedPath {
4883 introduction_node_id: nodes[2],
4884 blinding_point: ln_test_utils::pubkey(42),
4885 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4887 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4889 fee_proportional_millionths: 0,
4890 htlc_minimum_msat: 0,
4891 htlc_maximum_msat: 0,
4892 cltv_expiry_delta: 0,
4893 features: BlindedHopFeatures::empty(),
4895 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4896 .with_bolt12_features(bolt12_features.clone()).unwrap();
4897 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4899 // MPP to 3 2-hop blinded paths
4900 let mut blinded_path_node_0 = blinded_path.clone();
4901 blinded_path_node_0.introduction_node_id = nodes[0];
4902 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4903 let mut node_0_payinfo = blinded_payinfo.clone();
4904 node_0_payinfo.htlc_maximum_msat = 50_000;
4906 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4907 blinded_path_node_7.introduction_node_id = nodes[7];
4908 let mut node_7_payinfo = blinded_payinfo.clone();
4909 node_7_payinfo.htlc_maximum_msat = 60_000;
4911 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4912 blinded_path_node_1.introduction_node_id = nodes[1];
4913 let mut node_1_payinfo = blinded_payinfo.clone();
4914 node_1_payinfo.htlc_maximum_msat = 180_000;
4916 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4918 (node_0_payinfo, blinded_path_node_0),
4919 (node_7_payinfo, blinded_path_node_7),
4920 (node_1_payinfo, blinded_path_node_1)
4922 .with_bolt12_features(bolt12_features).unwrap();
4923 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4927 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4928 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4929 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4930 let scorer = ln_test_utils::TestScorer::new();
4931 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4932 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4934 // We need a route consisting of 3 paths:
4935 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4936 // To achieve this, the amount being transferred should be around
4937 // the total capacity of these 3 paths.
4939 // First, we set limits on these (previously unlimited) channels.
4940 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4942 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4943 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4944 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4945 short_channel_id: 1,
4948 cltv_expiry_delta: 0,
4949 htlc_minimum_msat: 0,
4950 htlc_maximum_msat: 100_000,
4952 fee_proportional_millionths: 0,
4953 excess_data: Vec::new()
4955 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4956 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4957 short_channel_id: 3,
4960 cltv_expiry_delta: 0,
4961 htlc_minimum_msat: 0,
4962 htlc_maximum_msat: 50_000,
4964 fee_proportional_millionths: 0,
4965 excess_data: Vec::new()
4968 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4969 // (total limit 60).
4970 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4971 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4972 short_channel_id: 12,
4975 cltv_expiry_delta: 0,
4976 htlc_minimum_msat: 0,
4977 htlc_maximum_msat: 60_000,
4979 fee_proportional_millionths: 0,
4980 excess_data: Vec::new()
4982 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4983 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4984 short_channel_id: 13,
4987 cltv_expiry_delta: 0,
4988 htlc_minimum_msat: 0,
4989 htlc_maximum_msat: 60_000,
4991 fee_proportional_millionths: 0,
4992 excess_data: Vec::new()
4995 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4996 // (total capacity 180 sats).
4997 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4998 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4999 short_channel_id: 2,
5002 cltv_expiry_delta: 0,
5003 htlc_minimum_msat: 0,
5004 htlc_maximum_msat: 200_000,
5006 fee_proportional_millionths: 0,
5007 excess_data: Vec::new()
5009 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5010 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5011 short_channel_id: 4,
5014 cltv_expiry_delta: 0,
5015 htlc_minimum_msat: 0,
5016 htlc_maximum_msat: 180_000,
5018 fee_proportional_millionths: 0,
5019 excess_data: Vec::new()
5023 // Attempt to route more than available results in a failure.
5024 let route_params = RouteParameters::from_payment_params_and_value(
5025 payment_params.clone(), 300_000);
5026 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5027 &our_id, &route_params, &network_graph.read_only(), None,
5028 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5029 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5030 } else { panic!(); }
5034 // Attempt to route while setting max_path_count to 0 results in a failure.
5035 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5036 let route_params = RouteParameters::from_payment_params_and_value(
5037 zero_payment_params, 100);
5038 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5039 &our_id, &route_params, &network_graph.read_only(), None,
5040 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5041 assert_eq!(err, "Can't find a route with no paths allowed.");
5042 } else { panic!(); }
5046 // Attempt to route while setting max_path_count to 3 results in a failure.
5047 // This is the case because the minimal_value_contribution_msat would require each path
5048 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5049 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5050 let route_params = RouteParameters::from_payment_params_and_value(
5051 fail_payment_params, 250_000);
5052 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5053 &our_id, &route_params, &network_graph.read_only(), None,
5054 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5055 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5056 } else { panic!(); }
5060 // Now, attempt to route 250 sats (just a bit below the capacity).
5061 // Our algorithm should provide us with these 3 paths.
5062 let route_params = RouteParameters::from_payment_params_and_value(
5063 payment_params.clone(), 250_000);
5064 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5065 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5066 assert_eq!(route.paths.len(), 3);
5067 let mut total_amount_paid_msat = 0;
5068 for path in &route.paths {
5069 if let Some(bt) = &path.blinded_tail {
5070 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5072 assert_eq!(path.hops.len(), 2);
5073 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5075 total_amount_paid_msat += path.final_value_msat();
5077 assert_eq!(total_amount_paid_msat, 250_000);
5081 // Attempt to route an exact amount is also fine
5082 let route_params = RouteParameters::from_payment_params_and_value(
5083 payment_params.clone(), 290_000);
5084 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5085 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5086 assert_eq!(route.paths.len(), 3);
5087 let mut total_amount_paid_msat = 0;
5088 for path in &route.paths {
5089 if payment_params.payee.blinded_route_hints().len() != 0 {
5090 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5091 if let Some(bt) = &path.blinded_tail {
5092 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5093 if bt.hops.len() > 1 {
5094 assert_eq!(path.hops.last().unwrap().pubkey,
5095 payment_params.payee.blinded_route_hints().iter()
5096 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5097 .map(|(_, p)| p.introduction_node_id).unwrap());
5099 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5102 assert_eq!(path.hops.len(), 2);
5103 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5105 total_amount_paid_msat += path.final_value_msat();
5107 assert_eq!(total_amount_paid_msat, 290_000);
5112 fn long_mpp_route_test() {
5113 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5114 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5115 let scorer = ln_test_utils::TestScorer::new();
5116 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5117 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5118 let config = UserConfig::default();
5119 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5120 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5123 // We need a route consisting of 3 paths:
5124 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5125 // Note that these paths overlap (channels 5, 12, 13).
5126 // We will route 300 sats.
5127 // Each path will have 100 sats capacity, those channels which
5128 // are used twice will have 200 sats capacity.
5130 // Disable other potential paths.
5131 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5132 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5133 short_channel_id: 2,
5136 cltv_expiry_delta: 0,
5137 htlc_minimum_msat: 0,
5138 htlc_maximum_msat: 100_000,
5140 fee_proportional_millionths: 0,
5141 excess_data: Vec::new()
5143 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5144 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5145 short_channel_id: 7,
5148 cltv_expiry_delta: 0,
5149 htlc_minimum_msat: 0,
5150 htlc_maximum_msat: 100_000,
5152 fee_proportional_millionths: 0,
5153 excess_data: Vec::new()
5156 // Path via {node0, node2} is channels {1, 3, 5}.
5157 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5158 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5159 short_channel_id: 1,
5162 cltv_expiry_delta: 0,
5163 htlc_minimum_msat: 0,
5164 htlc_maximum_msat: 100_000,
5166 fee_proportional_millionths: 0,
5167 excess_data: Vec::new()
5169 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5170 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5171 short_channel_id: 3,
5174 cltv_expiry_delta: 0,
5175 htlc_minimum_msat: 0,
5176 htlc_maximum_msat: 100_000,
5178 fee_proportional_millionths: 0,
5179 excess_data: Vec::new()
5182 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5183 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5184 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5185 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5186 short_channel_id: 5,
5189 cltv_expiry_delta: 0,
5190 htlc_minimum_msat: 0,
5191 htlc_maximum_msat: 200_000,
5193 fee_proportional_millionths: 0,
5194 excess_data: Vec::new()
5197 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5198 // Add 100 sats to the capacities of {12, 13}, because these channels
5199 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5200 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5201 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5202 short_channel_id: 12,
5205 cltv_expiry_delta: 0,
5206 htlc_minimum_msat: 0,
5207 htlc_maximum_msat: 200_000,
5209 fee_proportional_millionths: 0,
5210 excess_data: Vec::new()
5212 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5213 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5214 short_channel_id: 13,
5217 cltv_expiry_delta: 0,
5218 htlc_minimum_msat: 0,
5219 htlc_maximum_msat: 200_000,
5221 fee_proportional_millionths: 0,
5222 excess_data: Vec::new()
5225 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5226 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5227 short_channel_id: 6,
5230 cltv_expiry_delta: 0,
5231 htlc_minimum_msat: 0,
5232 htlc_maximum_msat: 100_000,
5234 fee_proportional_millionths: 0,
5235 excess_data: Vec::new()
5237 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5238 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5239 short_channel_id: 11,
5242 cltv_expiry_delta: 0,
5243 htlc_minimum_msat: 0,
5244 htlc_maximum_msat: 100_000,
5246 fee_proportional_millionths: 0,
5247 excess_data: Vec::new()
5250 // Path via {node7, node2} is channels {12, 13, 5}.
5251 // We already limited them to 200 sats (they are used twice for 100 sats).
5252 // Nothing to do here.
5255 // Attempt to route more than available results in a failure.
5256 let route_params = RouteParameters::from_payment_params_and_value(
5257 payment_params.clone(), 350_000);
5258 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5259 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5260 &scorer, &Default::default(), &random_seed_bytes) {
5261 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5262 } else { panic!(); }
5266 // Now, attempt to route 300 sats (exact amount we can route).
5267 // Our algorithm should provide us with these 3 paths, 100 sats each.
5268 let route_params = RouteParameters::from_payment_params_and_value(
5269 payment_params, 300_000);
5270 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5271 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5272 assert_eq!(route.paths.len(), 3);
5274 let mut total_amount_paid_msat = 0;
5275 for path in &route.paths {
5276 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5277 total_amount_paid_msat += path.final_value_msat();
5279 assert_eq!(total_amount_paid_msat, 300_000);
5285 fn mpp_cheaper_route_test() {
5286 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5287 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5288 let scorer = ln_test_utils::TestScorer::new();
5289 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5290 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5291 let config = UserConfig::default();
5292 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5293 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5296 // This test checks that if we have two cheaper paths and one more expensive path,
5297 // so that liquidity-wise any 2 of 3 combination is sufficient,
5298 // two cheaper paths will be taken.
5299 // These paths have equal available liquidity.
5301 // We need a combination of 3 paths:
5302 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5303 // Note that these paths overlap (channels 5, 12, 13).
5304 // Each path will have 100 sats capacity, those channels which
5305 // are used twice will have 200 sats capacity.
5307 // Disable other potential paths.
5308 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5309 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5310 short_channel_id: 2,
5313 cltv_expiry_delta: 0,
5314 htlc_minimum_msat: 0,
5315 htlc_maximum_msat: 100_000,
5317 fee_proportional_millionths: 0,
5318 excess_data: Vec::new()
5320 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5321 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5322 short_channel_id: 7,
5325 cltv_expiry_delta: 0,
5326 htlc_minimum_msat: 0,
5327 htlc_maximum_msat: 100_000,
5329 fee_proportional_millionths: 0,
5330 excess_data: Vec::new()
5333 // Path via {node0, node2} is channels {1, 3, 5}.
5334 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5335 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5336 short_channel_id: 1,
5339 cltv_expiry_delta: 0,
5340 htlc_minimum_msat: 0,
5341 htlc_maximum_msat: 100_000,
5343 fee_proportional_millionths: 0,
5344 excess_data: Vec::new()
5346 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5347 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5348 short_channel_id: 3,
5351 cltv_expiry_delta: 0,
5352 htlc_minimum_msat: 0,
5353 htlc_maximum_msat: 100_000,
5355 fee_proportional_millionths: 0,
5356 excess_data: Vec::new()
5359 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5360 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5361 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5362 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5363 short_channel_id: 5,
5366 cltv_expiry_delta: 0,
5367 htlc_minimum_msat: 0,
5368 htlc_maximum_msat: 200_000,
5370 fee_proportional_millionths: 0,
5371 excess_data: Vec::new()
5374 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5375 // Add 100 sats to the capacities of {12, 13}, because these channels
5376 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5377 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5378 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5379 short_channel_id: 12,
5382 cltv_expiry_delta: 0,
5383 htlc_minimum_msat: 0,
5384 htlc_maximum_msat: 200_000,
5386 fee_proportional_millionths: 0,
5387 excess_data: Vec::new()
5389 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5390 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5391 short_channel_id: 13,
5394 cltv_expiry_delta: 0,
5395 htlc_minimum_msat: 0,
5396 htlc_maximum_msat: 200_000,
5398 fee_proportional_millionths: 0,
5399 excess_data: Vec::new()
5402 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5403 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5404 short_channel_id: 6,
5407 cltv_expiry_delta: 0,
5408 htlc_minimum_msat: 0,
5409 htlc_maximum_msat: 100_000,
5410 fee_base_msat: 1_000,
5411 fee_proportional_millionths: 0,
5412 excess_data: Vec::new()
5414 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5415 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5416 short_channel_id: 11,
5419 cltv_expiry_delta: 0,
5420 htlc_minimum_msat: 0,
5421 htlc_maximum_msat: 100_000,
5423 fee_proportional_millionths: 0,
5424 excess_data: Vec::new()
5427 // Path via {node7, node2} is channels {12, 13, 5}.
5428 // We already limited them to 200 sats (they are used twice for 100 sats).
5429 // Nothing to do here.
5432 // Now, attempt to route 180 sats.
5433 // Our algorithm should provide us with these 2 paths.
5434 let route_params = RouteParameters::from_payment_params_and_value(
5435 payment_params, 180_000);
5436 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5437 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5438 assert_eq!(route.paths.len(), 2);
5440 let mut total_value_transferred_msat = 0;
5441 let mut total_paid_msat = 0;
5442 for path in &route.paths {
5443 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5444 total_value_transferred_msat += path.final_value_msat();
5445 for hop in &path.hops {
5446 total_paid_msat += hop.fee_msat;
5449 // If we paid fee, this would be higher.
5450 assert_eq!(total_value_transferred_msat, 180_000);
5451 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5452 assert_eq!(total_fees_paid, 0);
5457 fn fees_on_mpp_route_test() {
5458 // This test makes sure that MPP algorithm properly takes into account
5459 // fees charged on the channels, by making the fees impactful:
5460 // if the fee is not properly accounted for, the behavior is different.
5461 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5462 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5463 let scorer = ln_test_utils::TestScorer::new();
5464 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5465 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5466 let config = UserConfig::default();
5467 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5468 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5471 // We need a route consisting of 2 paths:
5472 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5473 // We will route 200 sats, Each path will have 100 sats capacity.
5475 // This test is not particularly stable: e.g.,
5476 // there's a way to route via {node0, node2, node4}.
5477 // It works while pathfinding is deterministic, but can be broken otherwise.
5478 // It's fine to ignore this concern for now.
5480 // Disable other potential paths.
5481 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5482 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5483 short_channel_id: 2,
5486 cltv_expiry_delta: 0,
5487 htlc_minimum_msat: 0,
5488 htlc_maximum_msat: 100_000,
5490 fee_proportional_millionths: 0,
5491 excess_data: Vec::new()
5494 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5495 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5496 short_channel_id: 7,
5499 cltv_expiry_delta: 0,
5500 htlc_minimum_msat: 0,
5501 htlc_maximum_msat: 100_000,
5503 fee_proportional_millionths: 0,
5504 excess_data: Vec::new()
5507 // Path via {node0, node2} is channels {1, 3, 5}.
5508 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5509 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5510 short_channel_id: 1,
5513 cltv_expiry_delta: 0,
5514 htlc_minimum_msat: 0,
5515 htlc_maximum_msat: 100_000,
5517 fee_proportional_millionths: 0,
5518 excess_data: Vec::new()
5520 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5521 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5522 short_channel_id: 3,
5525 cltv_expiry_delta: 0,
5526 htlc_minimum_msat: 0,
5527 htlc_maximum_msat: 100_000,
5529 fee_proportional_millionths: 0,
5530 excess_data: Vec::new()
5533 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5534 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5535 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5536 short_channel_id: 5,
5539 cltv_expiry_delta: 0,
5540 htlc_minimum_msat: 0,
5541 htlc_maximum_msat: 100_000,
5543 fee_proportional_millionths: 0,
5544 excess_data: Vec::new()
5547 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5548 // All channels should be 100 sats capacity. But for the fee experiment,
5549 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5550 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5551 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5552 // so no matter how large are other channels,
5553 // the whole path will be limited by 100 sats with just these 2 conditions:
5554 // - channel 12 capacity is 250 sats
5555 // - fee for channel 6 is 150 sats
5556 // Let's test this by enforcing these 2 conditions and removing other limits.
5557 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5558 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5559 short_channel_id: 12,
5562 cltv_expiry_delta: 0,
5563 htlc_minimum_msat: 0,
5564 htlc_maximum_msat: 250_000,
5566 fee_proportional_millionths: 0,
5567 excess_data: Vec::new()
5569 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5570 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5571 short_channel_id: 13,
5574 cltv_expiry_delta: 0,
5575 htlc_minimum_msat: 0,
5576 htlc_maximum_msat: MAX_VALUE_MSAT,
5578 fee_proportional_millionths: 0,
5579 excess_data: Vec::new()
5582 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5583 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5584 short_channel_id: 6,
5587 cltv_expiry_delta: 0,
5588 htlc_minimum_msat: 0,
5589 htlc_maximum_msat: MAX_VALUE_MSAT,
5590 fee_base_msat: 150_000,
5591 fee_proportional_millionths: 0,
5592 excess_data: Vec::new()
5594 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5595 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5596 short_channel_id: 11,
5599 cltv_expiry_delta: 0,
5600 htlc_minimum_msat: 0,
5601 htlc_maximum_msat: MAX_VALUE_MSAT,
5603 fee_proportional_millionths: 0,
5604 excess_data: Vec::new()
5608 // Attempt to route more than available results in a failure.
5609 let route_params = RouteParameters::from_payment_params_and_value(
5610 payment_params.clone(), 210_000);
5611 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5612 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5613 &scorer, &Default::default(), &random_seed_bytes) {
5614 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5615 } else { panic!(); }
5619 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5620 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5621 max_total_routing_fee_msat: Some(149_999) };
5622 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5623 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5624 &scorer, &Default::default(), &random_seed_bytes) {
5625 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5626 } else { panic!(); }
5630 // Now, attempt to route 200 sats (exact amount we can route).
5631 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5632 max_total_routing_fee_msat: Some(150_000) };
5633 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5634 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5635 assert_eq!(route.paths.len(), 2);
5637 let mut total_amount_paid_msat = 0;
5638 for path in &route.paths {
5639 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5640 total_amount_paid_msat += path.final_value_msat();
5642 assert_eq!(total_amount_paid_msat, 200_000);
5643 assert_eq!(route.get_total_fees(), 150_000);
5648 fn mpp_with_last_hops() {
5649 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5650 // via a single last-hop route hint, we'd fail to route if we first collected routes
5651 // totaling close but not quite enough to fund the full payment.
5653 // This was because we considered last-hop hints to have exactly the sought payment amount
5654 // instead of the amount we were trying to collect, needlessly limiting our path searching
5655 // at the very first hop.
5657 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5658 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5659 // to only have the remaining to-collect amount in available liquidity.
5661 // This bug appeared in production in some specific channel configurations.
5662 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5663 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5664 let scorer = ln_test_utils::TestScorer::new();
5665 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5666 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5667 let config = UserConfig::default();
5668 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
5669 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
5670 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5671 src_node_id: nodes[2],
5672 short_channel_id: 42,
5673 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5674 cltv_expiry_delta: 42,
5675 htlc_minimum_msat: None,
5676 htlc_maximum_msat: None,
5677 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5679 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5680 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5681 // would first use the no-fee route and then fail to find a path along the second route as
5682 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5683 // under 5% of our payment amount.
5684 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5685 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5686 short_channel_id: 1,
5689 cltv_expiry_delta: (5 << 4) | 5,
5690 htlc_minimum_msat: 0,
5691 htlc_maximum_msat: 99_000,
5692 fee_base_msat: u32::max_value(),
5693 fee_proportional_millionths: u32::max_value(),
5694 excess_data: Vec::new()
5696 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5697 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5698 short_channel_id: 2,
5701 cltv_expiry_delta: (5 << 4) | 3,
5702 htlc_minimum_msat: 0,
5703 htlc_maximum_msat: 99_000,
5704 fee_base_msat: u32::max_value(),
5705 fee_proportional_millionths: u32::max_value(),
5706 excess_data: Vec::new()
5708 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5709 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5710 short_channel_id: 4,
5713 cltv_expiry_delta: (4 << 4) | 1,
5714 htlc_minimum_msat: 0,
5715 htlc_maximum_msat: MAX_VALUE_MSAT,
5717 fee_proportional_millionths: 0,
5718 excess_data: Vec::new()
5720 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5721 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5722 short_channel_id: 13,
5724 flags: 0|2, // Channel disabled
5725 cltv_expiry_delta: (13 << 4) | 1,
5726 htlc_minimum_msat: 0,
5727 htlc_maximum_msat: MAX_VALUE_MSAT,
5729 fee_proportional_millionths: 2000000,
5730 excess_data: Vec::new()
5733 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5735 let route_params = RouteParameters::from_payment_params_and_value(
5736 payment_params, 100_000);
5737 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5738 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5739 assert_eq!(route.paths.len(), 2);
5740 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5741 // Paths are manually ordered ordered by SCID, so:
5742 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5743 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5744 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5745 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5746 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5747 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5748 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5749 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5750 assert_eq!(route.get_total_fees(), 1);
5751 assert_eq!(route.get_total_amount(), 100_000);
5755 fn drop_lowest_channel_mpp_route_test() {
5756 // This test checks that low-capacity channel is dropped when after
5757 // path finding we realize that we found more capacity than we need.
5758 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5759 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5760 let scorer = ln_test_utils::TestScorer::new();
5761 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5762 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5763 let config = UserConfig::default();
5764 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5765 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5767 .with_max_channel_saturation_power_of_half(0);
5769 // We need a route consisting of 3 paths:
5770 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5772 // The first and the second paths should be sufficient, but the third should be
5773 // cheaper, so that we select it but drop later.
5775 // First, we set limits on these (previously unlimited) channels.
5776 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5778 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5779 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5780 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5781 short_channel_id: 1,
5784 cltv_expiry_delta: 0,
5785 htlc_minimum_msat: 0,
5786 htlc_maximum_msat: 100_000,
5788 fee_proportional_millionths: 0,
5789 excess_data: Vec::new()
5791 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5792 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5793 short_channel_id: 3,
5796 cltv_expiry_delta: 0,
5797 htlc_minimum_msat: 0,
5798 htlc_maximum_msat: 50_000,
5800 fee_proportional_millionths: 0,
5801 excess_data: Vec::new()
5804 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5805 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5806 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5807 short_channel_id: 12,
5810 cltv_expiry_delta: 0,
5811 htlc_minimum_msat: 0,
5812 htlc_maximum_msat: 60_000,
5814 fee_proportional_millionths: 0,
5815 excess_data: Vec::new()
5817 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5818 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5819 short_channel_id: 13,
5822 cltv_expiry_delta: 0,
5823 htlc_minimum_msat: 0,
5824 htlc_maximum_msat: 60_000,
5826 fee_proportional_millionths: 0,
5827 excess_data: Vec::new()
5830 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5831 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5832 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5833 short_channel_id: 2,
5836 cltv_expiry_delta: 0,
5837 htlc_minimum_msat: 0,
5838 htlc_maximum_msat: 20_000,
5840 fee_proportional_millionths: 0,
5841 excess_data: Vec::new()
5843 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5844 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5845 short_channel_id: 4,
5848 cltv_expiry_delta: 0,
5849 htlc_minimum_msat: 0,
5850 htlc_maximum_msat: 20_000,
5852 fee_proportional_millionths: 0,
5853 excess_data: Vec::new()
5857 // Attempt to route more than available results in a failure.
5858 let route_params = RouteParameters::from_payment_params_and_value(
5859 payment_params.clone(), 150_000);
5860 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5861 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5862 &scorer, &Default::default(), &random_seed_bytes) {
5863 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5864 } else { panic!(); }
5868 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5869 // Our algorithm should provide us with these 3 paths.
5870 let route_params = RouteParameters::from_payment_params_and_value(
5871 payment_params.clone(), 125_000);
5872 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5873 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5874 assert_eq!(route.paths.len(), 3);
5875 let mut total_amount_paid_msat = 0;
5876 for path in &route.paths {
5877 assert_eq!(path.hops.len(), 2);
5878 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5879 total_amount_paid_msat += path.final_value_msat();
5881 assert_eq!(total_amount_paid_msat, 125_000);
5885 // Attempt to route without the last small cheap channel
5886 let route_params = RouteParameters::from_payment_params_and_value(
5887 payment_params, 90_000);
5888 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5889 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5890 assert_eq!(route.paths.len(), 2);
5891 let mut total_amount_paid_msat = 0;
5892 for path in &route.paths {
5893 assert_eq!(path.hops.len(), 2);
5894 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5895 total_amount_paid_msat += path.final_value_msat();
5897 assert_eq!(total_amount_paid_msat, 90_000);
5902 fn min_criteria_consistency() {
5903 // Test that we don't use an inconsistent metric between updating and walking nodes during
5904 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5905 // was updated with a different criterion from the heap sorting, resulting in loops in
5906 // calculated paths. We test for that specific case here.
5908 // We construct a network that looks like this:
5910 // node2 -1(3)2- node3
5914 // node1 -1(5)2- node4 -1(1)2- node6
5920 // We create a loop on the side of our real path - our destination is node 6, with a
5921 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5922 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5923 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5924 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5925 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5926 // "previous hop" being set to node 3, creating a loop in the path.
5927 let secp_ctx = Secp256k1::new();
5928 let logger = Arc::new(ln_test_utils::TestLogger::new());
5929 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5930 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5931 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5932 let scorer = ln_test_utils::TestScorer::new();
5933 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5934 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5935 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5937 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5938 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5939 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5940 short_channel_id: 6,
5943 cltv_expiry_delta: (6 << 4) | 0,
5944 htlc_minimum_msat: 0,
5945 htlc_maximum_msat: MAX_VALUE_MSAT,
5947 fee_proportional_millionths: 0,
5948 excess_data: Vec::new()
5950 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5952 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5953 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5954 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5955 short_channel_id: 5,
5958 cltv_expiry_delta: (5 << 4) | 0,
5959 htlc_minimum_msat: 0,
5960 htlc_maximum_msat: MAX_VALUE_MSAT,
5962 fee_proportional_millionths: 0,
5963 excess_data: Vec::new()
5965 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5967 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5968 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5969 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5970 short_channel_id: 4,
5973 cltv_expiry_delta: (4 << 4) | 0,
5974 htlc_minimum_msat: 0,
5975 htlc_maximum_msat: MAX_VALUE_MSAT,
5977 fee_proportional_millionths: 0,
5978 excess_data: Vec::new()
5980 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5982 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5983 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5984 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5985 short_channel_id: 3,
5988 cltv_expiry_delta: (3 << 4) | 0,
5989 htlc_minimum_msat: 0,
5990 htlc_maximum_msat: MAX_VALUE_MSAT,
5992 fee_proportional_millionths: 0,
5993 excess_data: Vec::new()
5995 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5997 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5998 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5999 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6000 short_channel_id: 2,
6003 cltv_expiry_delta: (2 << 4) | 0,
6004 htlc_minimum_msat: 0,
6005 htlc_maximum_msat: MAX_VALUE_MSAT,
6007 fee_proportional_millionths: 0,
6008 excess_data: Vec::new()
6011 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6012 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6013 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6014 short_channel_id: 1,
6017 cltv_expiry_delta: (1 << 4) | 0,
6018 htlc_minimum_msat: 100,
6019 htlc_maximum_msat: MAX_VALUE_MSAT,
6021 fee_proportional_millionths: 0,
6022 excess_data: Vec::new()
6024 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6027 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6028 let route_params = RouteParameters::from_payment_params_and_value(
6029 payment_params, 10_000);
6030 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6031 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6032 assert_eq!(route.paths.len(), 1);
6033 assert_eq!(route.paths[0].hops.len(), 3);
6035 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6036 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6037 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6038 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6039 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6040 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6042 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6043 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6044 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6045 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6046 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6047 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6049 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6050 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6051 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6052 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6053 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6054 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6060 fn exact_fee_liquidity_limit() {
6061 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6062 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6063 // we calculated fees on a higher value, resulting in us ignoring such paths.
6064 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6065 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6066 let scorer = ln_test_utils::TestScorer::new();
6067 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6068 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6069 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6071 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6073 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6074 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6075 short_channel_id: 2,
6078 cltv_expiry_delta: 0,
6079 htlc_minimum_msat: 0,
6080 htlc_maximum_msat: 85_000,
6082 fee_proportional_millionths: 0,
6083 excess_data: Vec::new()
6086 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6087 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6088 short_channel_id: 12,
6091 cltv_expiry_delta: (4 << 4) | 1,
6092 htlc_minimum_msat: 0,
6093 htlc_maximum_msat: 270_000,
6095 fee_proportional_millionths: 1000000,
6096 excess_data: Vec::new()
6100 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6101 // 200% fee charged channel 13 in the 1-to-2 direction.
6102 let mut route_params = RouteParameters::from_payment_params_and_value(
6103 payment_params, 90_000);
6104 route_params.max_total_routing_fee_msat = Some(90_000*2);
6105 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6106 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6107 assert_eq!(route.paths.len(), 1);
6108 assert_eq!(route.paths[0].hops.len(), 2);
6110 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6111 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6112 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6113 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6114 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6115 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6117 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6118 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6119 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6120 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6121 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6122 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6127 fn htlc_max_reduction_below_min() {
6128 // Test that if, while walking the graph, we reduce the value being sent to meet an
6129 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6130 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6131 // resulting in us thinking there is no possible path, even if other paths exist.
6132 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6133 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6134 let scorer = ln_test_utils::TestScorer::new();
6135 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6136 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6137 let config = UserConfig::default();
6138 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6139 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6142 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6143 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6144 // then try to send 90_000.
6145 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6146 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6147 short_channel_id: 2,
6150 cltv_expiry_delta: 0,
6151 htlc_minimum_msat: 0,
6152 htlc_maximum_msat: 80_000,
6154 fee_proportional_millionths: 0,
6155 excess_data: Vec::new()
6157 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6158 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6159 short_channel_id: 4,
6162 cltv_expiry_delta: (4 << 4) | 1,
6163 htlc_minimum_msat: 90_000,
6164 htlc_maximum_msat: MAX_VALUE_MSAT,
6166 fee_proportional_millionths: 0,
6167 excess_data: Vec::new()
6171 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6172 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6173 // expensive) channels 12-13 path.
6174 let mut route_params = RouteParameters::from_payment_params_and_value(
6175 payment_params, 90_000);
6176 route_params.max_total_routing_fee_msat = Some(90_000*2);
6177 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6178 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6179 assert_eq!(route.paths.len(), 1);
6180 assert_eq!(route.paths[0].hops.len(), 2);
6182 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6183 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6184 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6185 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6186 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6187 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6189 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6190 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6191 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6192 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6193 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6194 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6199 fn multiple_direct_first_hops() {
6200 // Previously we'd only ever considered one first hop path per counterparty.
6201 // However, as we don't restrict users to one channel per peer, we really need to support
6202 // looking at all first hop paths.
6203 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6204 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6205 // route over multiple channels with the same first hop.
6206 let secp_ctx = Secp256k1::new();
6207 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6208 let logger = Arc::new(ln_test_utils::TestLogger::new());
6209 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6210 let scorer = ln_test_utils::TestScorer::new();
6211 let config = UserConfig::default();
6212 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6213 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6215 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6216 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6219 let route_params = RouteParameters::from_payment_params_and_value(
6220 payment_params.clone(), 100_000);
6221 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6222 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6223 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6224 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6225 assert_eq!(route.paths.len(), 1);
6226 assert_eq!(route.paths[0].hops.len(), 1);
6228 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6229 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6230 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6233 let route_params = RouteParameters::from_payment_params_and_value(
6234 payment_params.clone(), 100_000);
6235 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6236 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6237 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6238 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6239 assert_eq!(route.paths.len(), 2);
6240 assert_eq!(route.paths[0].hops.len(), 1);
6241 assert_eq!(route.paths[1].hops.len(), 1);
6243 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6244 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6246 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6247 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6249 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6250 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6254 // If we have a bunch of outbound channels to the same node, where most are not
6255 // sufficient to pay the full payment, but one is, we should default to just using the
6256 // one single channel that has sufficient balance, avoiding MPP.
6258 // If we have several options above the 3xpayment value threshold, we should pick the
6259 // smallest of them, avoiding further fragmenting our available outbound balance to
6261 let route_params = RouteParameters::from_payment_params_and_value(
6262 payment_params, 100_000);
6263 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6264 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6265 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6266 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6267 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6268 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6269 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6270 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6271 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6272 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6273 assert_eq!(route.paths.len(), 1);
6274 assert_eq!(route.paths[0].hops.len(), 1);
6276 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6277 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6278 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6283 fn prefers_shorter_route_with_higher_fees() {
6284 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6285 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6286 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6288 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6289 let scorer = ln_test_utils::TestScorer::new();
6290 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6291 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6292 let route_params = RouteParameters::from_payment_params_and_value(
6293 payment_params.clone(), 100);
6294 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6295 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6296 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6298 assert_eq!(route.get_total_fees(), 100);
6299 assert_eq!(route.get_total_amount(), 100);
6300 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6302 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6303 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6304 let scorer = FixedPenaltyScorer::with_penalty(100);
6305 let route_params = RouteParameters::from_payment_params_and_value(
6306 payment_params, 100);
6307 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6308 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6309 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6311 assert_eq!(route.get_total_fees(), 300);
6312 assert_eq!(route.get_total_amount(), 100);
6313 assert_eq!(path, vec![2, 4, 7, 10]);
6316 struct BadChannelScorer {
6317 short_channel_id: u64,
6321 impl Writeable for BadChannelScorer {
6322 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6324 impl ScoreLookUp for BadChannelScorer {
6325 type ScoreParams = ();
6326 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6327 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6331 struct BadNodeScorer {
6336 impl Writeable for BadNodeScorer {
6337 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6340 impl ScoreLookUp for BadNodeScorer {
6341 type ScoreParams = ();
6342 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6343 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6348 fn avoids_routing_through_bad_channels_and_nodes() {
6349 let (secp_ctx, network, _, _, logger) = build_graph();
6350 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6351 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6352 let network_graph = network.read_only();
6354 // A path to nodes[6] exists when no penalties are applied to any channel.
6355 let scorer = ln_test_utils::TestScorer::new();
6356 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6357 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6358 let route_params = RouteParameters::from_payment_params_and_value(
6359 payment_params, 100);
6360 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6361 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6362 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6364 assert_eq!(route.get_total_fees(), 100);
6365 assert_eq!(route.get_total_amount(), 100);
6366 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6368 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6369 let scorer = BadChannelScorer { short_channel_id: 6 };
6370 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6371 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6372 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6374 assert_eq!(route.get_total_fees(), 300);
6375 assert_eq!(route.get_total_amount(), 100);
6376 assert_eq!(path, vec![2, 4, 7, 10]);
6378 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6379 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6380 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6381 &scorer, &Default::default(), &random_seed_bytes) {
6382 Err(LightningError { err, .. } ) => {
6383 assert_eq!(err, "Failed to find a path to the given destination");
6385 Ok(_) => panic!("Expected error"),
6390 fn total_fees_single_path() {
6392 paths: vec![Path { hops: vec![
6394 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6395 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6396 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6399 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6400 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6401 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6404 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6405 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6406 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6408 ], blinded_tail: None }],
6412 assert_eq!(route.get_total_fees(), 250);
6413 assert_eq!(route.get_total_amount(), 225);
6417 fn total_fees_multi_path() {
6419 paths: vec![Path { hops: vec![
6421 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6422 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6423 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6426 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6427 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6428 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6430 ], blinded_tail: None }, Path { hops: vec![
6432 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6433 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6434 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6437 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6438 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6439 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6441 ], blinded_tail: None }],
6445 assert_eq!(route.get_total_fees(), 200);
6446 assert_eq!(route.get_total_amount(), 300);
6450 fn total_empty_route_no_panic() {
6451 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6452 // would both panic if the route was completely empty. We test to ensure they return 0
6453 // here, even though its somewhat nonsensical as a route.
6454 let route = Route { paths: Vec::new(), route_params: None };
6456 assert_eq!(route.get_total_fees(), 0);
6457 assert_eq!(route.get_total_amount(), 0);
6461 fn limits_total_cltv_delta() {
6462 let (secp_ctx, network, _, _, logger) = build_graph();
6463 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6464 let network_graph = network.read_only();
6466 let scorer = ln_test_utils::TestScorer::new();
6468 // Make sure that generally there is at least one route available
6469 let feasible_max_total_cltv_delta = 1008;
6470 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6471 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6472 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6473 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6474 let route_params = RouteParameters::from_payment_params_and_value(
6475 feasible_payment_params, 100);
6476 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6477 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6478 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6479 assert_ne!(path.len(), 0);
6481 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6482 let fail_max_total_cltv_delta = 23;
6483 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6484 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6485 let route_params = RouteParameters::from_payment_params_and_value(
6486 fail_payment_params, 100);
6487 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6488 &Default::default(), &random_seed_bytes)
6490 Err(LightningError { err, .. } ) => {
6491 assert_eq!(err, "Failed to find a path to the given destination");
6493 Ok(_) => panic!("Expected error"),
6498 fn avoids_recently_failed_paths() {
6499 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6500 // randomly inserting channels into it until we can't find a route anymore.
6501 let (secp_ctx, network, _, _, logger) = build_graph();
6502 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6503 let network_graph = network.read_only();
6505 let scorer = ln_test_utils::TestScorer::new();
6506 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6507 .with_max_path_count(1);
6508 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6509 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6511 // We should be able to find a route initially, and then after we fail a few random
6512 // channels eventually we won't be able to any longer.
6513 let route_params = RouteParameters::from_payment_params_and_value(
6514 payment_params.clone(), 100);
6515 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6516 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6518 let route_params = RouteParameters::from_payment_params_and_value(
6519 payment_params.clone(), 100);
6520 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6521 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6523 for chan in route.paths[0].hops.iter() {
6524 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6526 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6527 % route.paths[0].hops.len();
6528 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6534 fn limits_path_length() {
6535 let (secp_ctx, network, _, _, logger) = build_line_graph();
6536 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6537 let network_graph = network.read_only();
6539 let scorer = ln_test_utils::TestScorer::new();
6540 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6541 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6543 // First check we can actually create a long route on this graph.
6544 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6545 let route_params = RouteParameters::from_payment_params_and_value(
6546 feasible_payment_params, 100);
6547 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6548 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6549 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6550 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6552 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6553 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6554 let route_params = RouteParameters::from_payment_params_and_value(
6555 fail_payment_params, 100);
6556 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6557 &Default::default(), &random_seed_bytes)
6559 Err(LightningError { err, .. } ) => {
6560 assert_eq!(err, "Failed to find a path to the given destination");
6562 Ok(_) => panic!("Expected error"),
6567 fn adds_and_limits_cltv_offset() {
6568 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6569 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6571 let scorer = ln_test_utils::TestScorer::new();
6573 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6574 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6575 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6576 let route_params = RouteParameters::from_payment_params_and_value(
6577 payment_params.clone(), 100);
6578 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6579 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6580 assert_eq!(route.paths.len(), 1);
6582 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6584 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6585 let mut route_default = route.clone();
6586 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6587 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6588 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6589 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6590 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6592 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6593 let mut route_limited = route.clone();
6594 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6595 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6596 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6597 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6598 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6602 fn adds_plausible_cltv_offset() {
6603 let (secp_ctx, network, _, _, logger) = build_graph();
6604 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6605 let network_graph = network.read_only();
6606 let network_nodes = network_graph.nodes();
6607 let network_channels = network_graph.channels();
6608 let scorer = ln_test_utils::TestScorer::new();
6609 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6610 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6611 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6613 let route_params = RouteParameters::from_payment_params_and_value(
6614 payment_params.clone(), 100);
6615 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6616 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6617 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6619 let mut path_plausibility = vec![];
6621 for p in route.paths {
6622 // 1. Select random observation point
6623 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6624 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6626 prng.process_in_place(&mut random_bytes);
6627 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6628 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6630 // 2. Calculate what CLTV expiry delta we would observe there
6631 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6633 // 3. Starting from the observation point, find candidate paths
6634 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6635 candidates.push_back((observation_point, vec![]));
6637 let mut found_plausible_candidate = false;
6639 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6640 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6641 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6642 found_plausible_candidate = true;
6643 break 'candidate_loop;
6647 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6648 for channel_id in &cur_node.channels {
6649 if let Some(channel_info) = network_channels.get(&channel_id) {
6650 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6651 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6652 if cur_path_cltv_deltas.iter().sum::<u32>()
6653 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6654 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6655 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6656 candidates.push_back((*next_id, new_path_cltv_deltas));
6664 path_plausibility.push(found_plausible_candidate);
6666 assert!(path_plausibility.iter().all(|x| *x));
6670 fn builds_correct_path_from_hops() {
6671 let (secp_ctx, network, _, _, logger) = build_graph();
6672 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6673 let network_graph = network.read_only();
6675 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6676 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6678 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6679 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6680 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6681 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6682 Arc::clone(&logger), &random_seed_bytes).unwrap();
6683 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6684 assert_eq!(hops.len(), route.paths[0].hops.len());
6685 for (idx, hop_pubkey) in hops.iter().enumerate() {
6686 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6691 fn avoids_saturating_channels() {
6692 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6693 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6694 let decay_params = ProbabilisticScoringDecayParameters::default();
6695 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6697 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6698 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6699 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6700 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6701 short_channel_id: 4,
6704 cltv_expiry_delta: (4 << 4) | 1,
6705 htlc_minimum_msat: 0,
6706 htlc_maximum_msat: 250_000_000,
6708 fee_proportional_millionths: 0,
6709 excess_data: Vec::new()
6711 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6712 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6713 short_channel_id: 13,
6716 cltv_expiry_delta: (13 << 4) | 1,
6717 htlc_minimum_msat: 0,
6718 htlc_maximum_msat: 250_000_000,
6720 fee_proportional_millionths: 0,
6721 excess_data: Vec::new()
6724 let config = UserConfig::default();
6725 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6726 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6728 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6729 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6730 // 100,000 sats is less than the available liquidity on each channel, set above.
6731 let route_params = RouteParameters::from_payment_params_and_value(
6732 payment_params, 100_000_000);
6733 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6734 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6735 assert_eq!(route.paths.len(), 2);
6736 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6737 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6740 #[cfg(not(feature = "no-std"))]
6741 pub(super) fn random_init_seed() -> u64 {
6742 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6743 use core::hash::{BuildHasher, Hasher};
6744 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6745 println!("Using seed of {}", seed);
6750 #[cfg(not(feature = "no-std"))]
6751 fn generate_routes() {
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 = super::Bolt11InvoiceFeatures::empty();
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_routes_mpp() {
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(), 0, 2);
6792 #[cfg(not(feature = "no-std"))]
6793 fn generate_large_mpp_routes() {
6794 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6796 let logger = ln_test_utils::TestLogger::new();
6797 let graph = match super::bench_utils::read_network_graph(&logger) {
6805 let params = ProbabilisticScoringFeeParameters::default();
6806 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6807 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6809 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6813 fn honors_manual_penalties() {
6814 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6815 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6817 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6818 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6820 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6821 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6823 // First check set manual penalties are returned by the scorer.
6824 let usage = ChannelUsage {
6826 inflight_htlc_msat: 0,
6827 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6829 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6830 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6831 let network_graph = network_graph.read_only();
6832 let channels = network_graph.channels();
6833 let channel = channels.get(&5).unwrap();
6834 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
6835 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop {
6837 short_channel_id: 5,
6839 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
6841 // Then check we can get a normal route
6842 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6843 let route_params = RouteParameters::from_payment_params_and_value(
6844 payment_params, 100);
6845 let route = get_route(&our_id, &route_params, &network_graph, None,
6846 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6847 assert!(route.is_ok());
6849 // Then check that we can't get a route if we ban an intermediate node.
6850 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6851 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6852 assert!(route.is_err());
6854 // Finally make sure we can route again, when we remove the ban.
6855 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6856 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6857 assert!(route.is_ok());
6861 fn abide_by_route_hint_max_htlc() {
6862 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6863 // params in the final route.
6864 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6865 let netgraph = network_graph.read_only();
6866 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6867 let scorer = ln_test_utils::TestScorer::new();
6868 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6869 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6870 let config = UserConfig::default();
6872 let max_htlc_msat = 50_000;
6873 let route_hint_1 = RouteHint(vec![RouteHintHop {
6874 src_node_id: nodes[2],
6875 short_channel_id: 42,
6878 proportional_millionths: 0,
6880 cltv_expiry_delta: 10,
6881 htlc_minimum_msat: None,
6882 htlc_maximum_msat: Some(max_htlc_msat),
6884 let dest_node_id = ln_test_utils::pubkey(42);
6885 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6886 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6887 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6890 // Make sure we'll error if our route hints don't have enough liquidity according to their
6891 // htlc_maximum_msat.
6892 let mut route_params = RouteParameters::from_payment_params_and_value(
6893 payment_params, max_htlc_msat + 1);
6894 route_params.max_total_routing_fee_msat = None;
6895 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6896 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6899 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6900 } else { panic!(); }
6902 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6903 let mut route_hint_2 = route_hint_1.clone();
6904 route_hint_2.0[0].short_channel_id = 43;
6905 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6906 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6907 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6909 let mut route_params = RouteParameters::from_payment_params_and_value(
6910 payment_params, max_htlc_msat + 1);
6911 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6912 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6913 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6914 assert_eq!(route.paths.len(), 2);
6915 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6916 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6920 fn direct_channel_to_hints_with_max_htlc() {
6921 // Check that if we have a first hop channel peer that's connected to multiple provided route
6922 // hints, that we properly split the payment between the route hints if needed.
6923 let logger = Arc::new(ln_test_utils::TestLogger::new());
6924 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6925 let scorer = ln_test_utils::TestScorer::new();
6926 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6927 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6928 let config = UserConfig::default();
6930 let our_node_id = ln_test_utils::pubkey(42);
6931 let intermed_node_id = ln_test_utils::pubkey(43);
6932 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6934 let amt_msat = 900_000;
6935 let max_htlc_msat = 500_000;
6936 let route_hint_1 = RouteHint(vec![RouteHintHop {
6937 src_node_id: intermed_node_id,
6938 short_channel_id: 44,
6941 proportional_millionths: 0,
6943 cltv_expiry_delta: 10,
6944 htlc_minimum_msat: None,
6945 htlc_maximum_msat: Some(max_htlc_msat),
6947 src_node_id: intermed_node_id,
6948 short_channel_id: 45,
6951 proportional_millionths: 0,
6953 cltv_expiry_delta: 10,
6954 htlc_minimum_msat: None,
6955 // Check that later route hint max htlcs don't override earlier ones
6956 htlc_maximum_msat: Some(max_htlc_msat - 50),
6958 let mut route_hint_2 = route_hint_1.clone();
6959 route_hint_2.0[0].short_channel_id = 46;
6960 route_hint_2.0[1].short_channel_id = 47;
6961 let dest_node_id = ln_test_utils::pubkey(44);
6962 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6963 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6964 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6967 let route_params = RouteParameters::from_payment_params_and_value(
6968 payment_params, amt_msat);
6969 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6970 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6971 &Default::default(), &random_seed_bytes).unwrap();
6972 assert_eq!(route.paths.len(), 2);
6973 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6974 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6975 assert_eq!(route.get_total_amount(), amt_msat);
6977 // Re-run but with two first hop channels connected to the same route hint peers that must be
6979 let first_hops = vec![
6980 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6981 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6983 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6984 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6985 &Default::default(), &random_seed_bytes).unwrap();
6986 assert_eq!(route.paths.len(), 2);
6987 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6988 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6989 assert_eq!(route.get_total_amount(), amt_msat);
6991 // Make sure this works for blinded route hints.
6992 let blinded_path = BlindedPath {
6993 introduction_node_id: intermed_node_id,
6994 blinding_point: ln_test_utils::pubkey(42),
6996 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6997 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
7000 let blinded_payinfo = BlindedPayInfo {
7002 fee_proportional_millionths: 0,
7003 htlc_minimum_msat: 1,
7004 htlc_maximum_msat: max_htlc_msat,
7005 cltv_expiry_delta: 10,
7006 features: BlindedHopFeatures::empty(),
7008 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7009 let payment_params = PaymentParameters::blinded(vec![
7010 (blinded_payinfo.clone(), blinded_path.clone()),
7011 (blinded_payinfo.clone(), blinded_path.clone())])
7012 .with_bolt12_features(bolt12_features).unwrap();
7013 let route_params = RouteParameters::from_payment_params_and_value(
7014 payment_params, amt_msat);
7015 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7016 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7017 &Default::default(), &random_seed_bytes).unwrap();
7018 assert_eq!(route.paths.len(), 2);
7019 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7020 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7021 assert_eq!(route.get_total_amount(), amt_msat);
7025 fn blinded_route_ser() {
7026 let blinded_path_1 = BlindedPath {
7027 introduction_node_id: ln_test_utils::pubkey(42),
7028 blinding_point: ln_test_utils::pubkey(43),
7030 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7031 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7034 let blinded_path_2 = BlindedPath {
7035 introduction_node_id: ln_test_utils::pubkey(46),
7036 blinding_point: ln_test_utils::pubkey(47),
7038 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7039 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7042 // (De)serialize a Route with 1 blinded path out of two total paths.
7043 let mut route = Route { paths: vec![Path {
7044 hops: vec![RouteHop {
7045 pubkey: ln_test_utils::pubkey(50),
7046 node_features: NodeFeatures::empty(),
7047 short_channel_id: 42,
7048 channel_features: ChannelFeatures::empty(),
7050 cltv_expiry_delta: 0,
7051 maybe_announced_channel: true,
7053 blinded_tail: Some(BlindedTail {
7054 hops: blinded_path_1.blinded_hops,
7055 blinding_point: blinded_path_1.blinding_point,
7056 excess_final_cltv_expiry_delta: 40,
7057 final_value_msat: 100,
7059 hops: vec![RouteHop {
7060 pubkey: ln_test_utils::pubkey(51),
7061 node_features: NodeFeatures::empty(),
7062 short_channel_id: 43,
7063 channel_features: ChannelFeatures::empty(),
7065 cltv_expiry_delta: 0,
7066 maybe_announced_channel: true,
7067 }], blinded_tail: None }],
7070 let encoded_route = route.encode();
7071 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7072 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7073 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7075 // (De)serialize a Route with two paths, each containing a blinded tail.
7076 route.paths[1].blinded_tail = Some(BlindedTail {
7077 hops: blinded_path_2.blinded_hops,
7078 blinding_point: blinded_path_2.blinding_point,
7079 excess_final_cltv_expiry_delta: 41,
7080 final_value_msat: 101,
7082 let encoded_route = route.encode();
7083 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7084 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7085 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7089 fn blinded_path_inflight_processing() {
7090 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7091 // account for the blinded tail's final amount_msat.
7092 let mut inflight_htlcs = InFlightHtlcs::new();
7093 let blinded_path = BlindedPath {
7094 introduction_node_id: ln_test_utils::pubkey(43),
7095 blinding_point: ln_test_utils::pubkey(48),
7096 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7099 hops: vec![RouteHop {
7100 pubkey: ln_test_utils::pubkey(42),
7101 node_features: NodeFeatures::empty(),
7102 short_channel_id: 42,
7103 channel_features: ChannelFeatures::empty(),
7105 cltv_expiry_delta: 0,
7106 maybe_announced_channel: false,
7109 pubkey: blinded_path.introduction_node_id,
7110 node_features: NodeFeatures::empty(),
7111 short_channel_id: 43,
7112 channel_features: ChannelFeatures::empty(),
7114 cltv_expiry_delta: 0,
7115 maybe_announced_channel: false,
7117 blinded_tail: Some(BlindedTail {
7118 hops: blinded_path.blinded_hops,
7119 blinding_point: blinded_path.blinding_point,
7120 excess_final_cltv_expiry_delta: 0,
7121 final_value_msat: 200,
7124 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7125 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7126 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7130 fn blinded_path_cltv_shadow_offset() {
7131 // Make sure we add a shadow offset when sending to blinded paths.
7132 let blinded_path = BlindedPath {
7133 introduction_node_id: ln_test_utils::pubkey(43),
7134 blinding_point: ln_test_utils::pubkey(44),
7136 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7137 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7140 let mut route = Route { paths: vec![Path {
7141 hops: vec![RouteHop {
7142 pubkey: ln_test_utils::pubkey(42),
7143 node_features: NodeFeatures::empty(),
7144 short_channel_id: 42,
7145 channel_features: ChannelFeatures::empty(),
7147 cltv_expiry_delta: 0,
7148 maybe_announced_channel: false,
7151 pubkey: blinded_path.introduction_node_id,
7152 node_features: NodeFeatures::empty(),
7153 short_channel_id: 43,
7154 channel_features: ChannelFeatures::empty(),
7156 cltv_expiry_delta: 0,
7157 maybe_announced_channel: false,
7160 blinded_tail: Some(BlindedTail {
7161 hops: blinded_path.blinded_hops,
7162 blinding_point: blinded_path.blinding_point,
7163 excess_final_cltv_expiry_delta: 0,
7164 final_value_msat: 200,
7166 }], route_params: None};
7168 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7169 let (_, network_graph, _, _, _) = build_line_graph();
7170 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7171 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7172 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7176 fn simple_blinded_route_hints() {
7177 do_simple_blinded_route_hints(1);
7178 do_simple_blinded_route_hints(2);
7179 do_simple_blinded_route_hints(3);
7182 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7183 // Check that we can generate a route to a blinded path with the expected hops.
7184 let (secp_ctx, network, _, _, logger) = build_graph();
7185 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7186 let network_graph = network.read_only();
7188 let scorer = ln_test_utils::TestScorer::new();
7189 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7190 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7192 let mut blinded_path = BlindedPath {
7193 introduction_node_id: nodes[2],
7194 blinding_point: ln_test_utils::pubkey(42),
7195 blinded_hops: Vec::with_capacity(num_blinded_hops),
7197 for i in 0..num_blinded_hops {
7198 blinded_path.blinded_hops.push(
7199 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7202 let blinded_payinfo = BlindedPayInfo {
7204 fee_proportional_millionths: 500,
7205 htlc_minimum_msat: 1000,
7206 htlc_maximum_msat: 100_000_000,
7207 cltv_expiry_delta: 15,
7208 features: BlindedHopFeatures::empty(),
7211 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7212 let route_params = RouteParameters::from_payment_params_and_value(
7213 payment_params, 1001);
7214 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7215 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7216 assert_eq!(route.paths.len(), 1);
7217 assert_eq!(route.paths[0].hops.len(), 2);
7219 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7220 assert_eq!(tail.hops, blinded_path.blinded_hops);
7221 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7222 assert_eq!(tail.final_value_msat, 1001);
7224 let final_hop = route.paths[0].hops.last().unwrap();
7225 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
7226 if tail.hops.len() > 1 {
7227 assert_eq!(final_hop.fee_msat,
7228 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7229 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7231 assert_eq!(final_hop.fee_msat, 0);
7232 assert_eq!(final_hop.cltv_expiry_delta, 0);
7237 fn blinded_path_routing_errors() {
7238 // Check that we can generate a route to a blinded path with the expected hops.
7239 let (secp_ctx, network, _, _, logger) = build_graph();
7240 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7241 let network_graph = network.read_only();
7243 let scorer = ln_test_utils::TestScorer::new();
7244 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7245 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7247 let mut invalid_blinded_path = BlindedPath {
7248 introduction_node_id: nodes[2],
7249 blinding_point: ln_test_utils::pubkey(42),
7251 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7254 let blinded_payinfo = BlindedPayInfo {
7256 fee_proportional_millionths: 500,
7257 htlc_minimum_msat: 1000,
7258 htlc_maximum_msat: 100_000_000,
7259 cltv_expiry_delta: 15,
7260 features: BlindedHopFeatures::empty(),
7263 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7264 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7265 let payment_params = PaymentParameters::blinded(vec![
7266 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7267 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7268 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7269 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7270 &scorer, &Default::default(), &random_seed_bytes)
7272 Err(LightningError { err, .. }) => {
7273 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7275 _ => panic!("Expected error")
7278 invalid_blinded_path.introduction_node_id = our_id;
7279 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7280 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7281 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7282 &Default::default(), &random_seed_bytes)
7284 Err(LightningError { err, .. }) => {
7285 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7287 _ => panic!("Expected error")
7290 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7291 invalid_blinded_path.blinded_hops.clear();
7292 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7293 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7294 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7295 &Default::default(), &random_seed_bytes)
7297 Err(LightningError { err, .. }) => {
7298 assert_eq!(err, "0-hop blinded path provided");
7300 _ => panic!("Expected error")
7305 fn matching_intro_node_paths_provided() {
7306 // Check that if multiple blinded paths with the same intro node are provided in payment
7307 // parameters, we'll return the correct paths in the resulting MPP route.
7308 let (secp_ctx, network, _, _, logger) = build_graph();
7309 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7310 let network_graph = network.read_only();
7312 let scorer = ln_test_utils::TestScorer::new();
7313 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7314 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7315 let config = UserConfig::default();
7317 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7318 let blinded_path_1 = BlindedPath {
7319 introduction_node_id: nodes[2],
7320 blinding_point: ln_test_utils::pubkey(42),
7322 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7323 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7326 let blinded_payinfo_1 = BlindedPayInfo {
7328 fee_proportional_millionths: 0,
7329 htlc_minimum_msat: 0,
7330 htlc_maximum_msat: 30_000,
7331 cltv_expiry_delta: 0,
7332 features: BlindedHopFeatures::empty(),
7335 let mut blinded_path_2 = blinded_path_1.clone();
7336 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7337 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7338 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7340 let blinded_hints = vec![
7341 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7342 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7344 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7345 .with_bolt12_features(bolt12_features).unwrap();
7347 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7348 route_params.max_total_routing_fee_msat = Some(100_000);
7349 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7350 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7351 assert_eq!(route.paths.len(), 2);
7352 let mut total_amount_paid_msat = 0;
7353 for path in route.paths.into_iter() {
7354 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7355 if let Some(bt) = &path.blinded_tail {
7356 assert_eq!(bt.blinding_point,
7357 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7358 .map(|(_, bp)| bp.blinding_point).unwrap());
7359 } else { panic!(); }
7360 total_amount_paid_msat += path.final_value_msat();
7362 assert_eq!(total_amount_paid_msat, 100_000);
7366 fn direct_to_intro_node() {
7367 // This previously caused a debug panic in the router when asserting
7368 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7369 // direct channels we failed to account for the fee charged for use of the blinded path.
7372 // node0 -1(1)2 - node1
7373 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7374 // doesn't account for the blinded path fee.
7376 let secp_ctx = Secp256k1::new();
7377 let logger = Arc::new(ln_test_utils::TestLogger::new());
7378 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7379 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7380 let scorer = ln_test_utils::TestScorer::new();
7381 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7382 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7384 let amt_msat = 10_000_000;
7385 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7386 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7387 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7388 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7389 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7390 short_channel_id: 1,
7393 cltv_expiry_delta: 42,
7394 htlc_minimum_msat: 1_000,
7395 htlc_maximum_msat: 10_000_000,
7397 fee_proportional_millionths: 0,
7398 excess_data: Vec::new()
7400 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7401 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7402 short_channel_id: 1,
7405 cltv_expiry_delta: 42,
7406 htlc_minimum_msat: 1_000,
7407 htlc_maximum_msat: 10_000_000,
7409 fee_proportional_millionths: 0,
7410 excess_data: Vec::new()
7412 let first_hops = vec![
7413 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7415 let blinded_path = BlindedPath {
7416 introduction_node_id: nodes[1],
7417 blinding_point: ln_test_utils::pubkey(42),
7419 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7420 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7423 let blinded_payinfo = BlindedPayInfo {
7424 fee_base_msat: 1000,
7425 fee_proportional_millionths: 0,
7426 htlc_minimum_msat: 1000,
7427 htlc_maximum_msat: MAX_VALUE_MSAT,
7428 cltv_expiry_delta: 0,
7429 features: BlindedHopFeatures::empty(),
7431 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7433 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7435 let netgraph = network_graph.read_only();
7436 let route_params = RouteParameters::from_payment_params_and_value(
7437 payment_params.clone(), amt_msat);
7438 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7439 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7440 &Default::default(), &random_seed_bytes) {
7441 assert_eq!(err, "Failed to find a path to the given destination");
7442 } else { panic!("Expected error") }
7444 // Sending an exact amount accounting for the blinded path fee works.
7445 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7446 let route_params = RouteParameters::from_payment_params_and_value(
7447 payment_params, amt_minus_blinded_path_fee);
7448 let route = get_route(&nodes[0], &route_params, &netgraph,
7449 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7450 &Default::default(), &random_seed_bytes).unwrap();
7451 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7452 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7456 fn direct_to_matching_intro_nodes() {
7457 // This previously caused us to enter `unreachable` code in the following situation:
7458 // 1. We add a route candidate for intro_node contributing a high amount
7459 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7460 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7461 // amount, and update our route candidate for intro_node for the lower amount
7462 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7463 // lower contribution amount, but fail (this was previously caused by failure to account for
7464 // blinded path fees when adding first_hop<>intro_node candidates)
7465 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7466 // candidate still thinks its path is contributing the original higher amount. This caused us
7467 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7469 let secp_ctx = Secp256k1::new();
7470 let logger = Arc::new(ln_test_utils::TestLogger::new());
7471 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7472 let scorer = ln_test_utils::TestScorer::new();
7473 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7474 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7475 let config = UserConfig::default();
7477 // Values are taken from the fuzz input that uncovered this panic.
7478 let amt_msat = 21_7020_5185_1403_2640;
7479 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7480 let first_hops = vec![
7481 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7482 18446744073709551615)];
7484 let blinded_path = BlindedPath {
7485 introduction_node_id: nodes[1],
7486 blinding_point: ln_test_utils::pubkey(42),
7488 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7489 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7492 let blinded_payinfo = BlindedPayInfo {
7493 fee_base_msat: 5046_2720,
7494 fee_proportional_millionths: 0,
7495 htlc_minimum_msat: 4503_5996_2737_0496,
7496 htlc_maximum_msat: 45_0359_9627_3704_9600,
7497 cltv_expiry_delta: 0,
7498 features: BlindedHopFeatures::empty(),
7500 let mut blinded_hints = vec![
7501 (blinded_payinfo.clone(), blinded_path.clone()),
7502 (blinded_payinfo.clone(), blinded_path.clone()),
7504 blinded_hints[1].0.fee_base_msat = 419_4304;
7505 blinded_hints[1].0.fee_proportional_millionths = 257;
7506 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7507 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7508 blinded_hints[1].0.cltv_expiry_delta = 0;
7510 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7511 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7512 .with_bolt12_features(bolt12_features).unwrap();
7514 let netgraph = network_graph.read_only();
7515 let route_params = RouteParameters::from_payment_params_and_value(
7516 payment_params, amt_msat);
7517 let route = get_route(&nodes[0], &route_params, &netgraph,
7518 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7519 &Default::default(), &random_seed_bytes).unwrap();
7520 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7521 assert_eq!(route.get_total_amount(), amt_msat);
7525 fn we_are_intro_node_candidate_hops() {
7526 // This previously led to a panic in the router because we'd generate a Path with only a
7527 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7528 // where the origin node is the intro node. We now fully disallow considering candidate hops
7529 // where the origin node is the intro node.
7530 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7531 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7532 let scorer = ln_test_utils::TestScorer::new();
7533 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7534 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7535 let config = UserConfig::default();
7537 // Values are taken from the fuzz input that uncovered this panic.
7538 let amt_msat = 21_7020_5185_1423_0019;
7540 let blinded_path = BlindedPath {
7541 introduction_node_id: our_id,
7542 blinding_point: ln_test_utils::pubkey(42),
7544 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7545 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7548 let blinded_payinfo = BlindedPayInfo {
7549 fee_base_msat: 5052_9027,
7550 fee_proportional_millionths: 0,
7551 htlc_minimum_msat: 21_7020_5185_1423_0019,
7552 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7553 cltv_expiry_delta: 0,
7554 features: BlindedHopFeatures::empty(),
7556 let mut blinded_hints = vec![
7557 (blinded_payinfo.clone(), blinded_path.clone()),
7558 (blinded_payinfo.clone(), blinded_path.clone()),
7560 blinded_hints[1].1.introduction_node_id = nodes[6];
7562 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7563 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7564 .with_bolt12_features(bolt12_features.clone()).unwrap();
7566 let netgraph = network_graph.read_only();
7567 let route_params = RouteParameters::from_payment_params_and_value(
7568 payment_params, amt_msat);
7569 if let Err(LightningError { err, .. }) = get_route(
7570 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7572 assert_eq!(err, "Failed to find a path to the given destination");
7577 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7578 // This previously led to a debug panic in the router because we'd find an invalid Path with
7579 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7580 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7581 // the payment, when it was intended to only include the final value of the payment.
7582 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7583 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7584 let scorer = ln_test_utils::TestScorer::new();
7585 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7586 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7587 let config = UserConfig::default();
7589 // Values are taken from the fuzz input that uncovered this panic.
7590 let amt_msat = 21_7020_5185_1423_0019;
7592 let blinded_path = BlindedPath {
7593 introduction_node_id: our_id,
7594 blinding_point: ln_test_utils::pubkey(42),
7596 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7597 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7600 let blinded_payinfo = BlindedPayInfo {
7601 fee_base_msat: 10_4425_1395,
7602 fee_proportional_millionths: 0,
7603 htlc_minimum_msat: 21_7301_9934_9094_0931,
7604 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7605 cltv_expiry_delta: 0,
7606 features: BlindedHopFeatures::empty(),
7608 let mut blinded_hints = vec![
7609 (blinded_payinfo.clone(), blinded_path.clone()),
7610 (blinded_payinfo.clone(), blinded_path.clone()),
7611 (blinded_payinfo.clone(), blinded_path.clone()),
7613 blinded_hints[1].0.fee_base_msat = 5052_9027;
7614 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7615 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7617 blinded_hints[2].1.introduction_node_id = nodes[6];
7619 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7620 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7621 .with_bolt12_features(bolt12_features.clone()).unwrap();
7623 let netgraph = network_graph.read_only();
7624 let route_params = RouteParameters::from_payment_params_and_value(
7625 payment_params, amt_msat);
7626 if let Err(LightningError { err, .. }) = get_route(
7627 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7629 assert_eq!(err, "Failed to find a path to the given destination");
7634 fn min_htlc_overpay_violates_max_htlc() {
7635 do_min_htlc_overpay_violates_max_htlc(true);
7636 do_min_htlc_overpay_violates_max_htlc(false);
7638 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7639 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7640 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7641 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7642 // that the used liquidity for a hop was less than its available liquidity limit.
7643 let secp_ctx = Secp256k1::new();
7644 let logger = Arc::new(ln_test_utils::TestLogger::new());
7645 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7646 let scorer = ln_test_utils::TestScorer::new();
7647 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7648 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7649 let config = UserConfig::default();
7651 // Values are taken from the fuzz input that uncovered this panic.
7652 let amt_msat = 7_4009_8048;
7653 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7654 let first_hop_outbound_capacity = 2_7345_2000;
7655 let first_hops = vec![get_channel_details(
7656 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7657 first_hop_outbound_capacity
7660 let base_fee = 1_6778_3453;
7661 let htlc_min = 2_5165_8240;
7662 let payment_params = if blinded_payee {
7663 let blinded_path = BlindedPath {
7664 introduction_node_id: nodes[0],
7665 blinding_point: ln_test_utils::pubkey(42),
7667 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7668 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7671 let blinded_payinfo = BlindedPayInfo {
7672 fee_base_msat: base_fee,
7673 fee_proportional_millionths: 0,
7674 htlc_minimum_msat: htlc_min,
7675 htlc_maximum_msat: htlc_min * 1000,
7676 cltv_expiry_delta: 0,
7677 features: BlindedHopFeatures::empty(),
7679 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7680 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7681 .with_bolt12_features(bolt12_features.clone()).unwrap()
7683 let route_hint = RouteHint(vec![RouteHintHop {
7684 src_node_id: nodes[0],
7685 short_channel_id: 42,
7687 base_msat: base_fee,
7688 proportional_millionths: 0,
7690 cltv_expiry_delta: 10,
7691 htlc_minimum_msat: Some(htlc_min),
7692 htlc_maximum_msat: None,
7695 PaymentParameters::from_node_id(nodes[1], 42)
7696 .with_route_hints(vec![route_hint]).unwrap()
7697 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7700 let netgraph = network_graph.read_only();
7701 let route_params = RouteParameters::from_payment_params_and_value(
7702 payment_params, amt_msat);
7703 if let Err(LightningError { err, .. }) = get_route(
7704 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7705 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7707 assert_eq!(err, "Failed to find a path to the given destination");
7712 fn previously_used_liquidity_violates_max_htlc() {
7713 do_previously_used_liquidity_violates_max_htlc(true);
7714 do_previously_used_liquidity_violates_max_htlc(false);
7717 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7718 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7719 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7720 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7721 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7722 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7723 let secp_ctx = Secp256k1::new();
7724 let logger = Arc::new(ln_test_utils::TestLogger::new());
7725 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7726 let scorer = ln_test_utils::TestScorer::new();
7727 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7728 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7729 let config = UserConfig::default();
7731 // Values are taken from the fuzz input that uncovered this panic.
7732 let amt_msat = 52_4288;
7733 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7734 let first_hops = vec![get_channel_details(
7735 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7736 ), get_channel_details(
7737 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7740 let base_fees = [0, 425_9840, 0, 0];
7741 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7742 let payment_params = if blinded_payee {
7743 let blinded_path = BlindedPath {
7744 introduction_node_id: nodes[0],
7745 blinding_point: ln_test_utils::pubkey(42),
7747 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7748 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7751 let mut blinded_hints = Vec::new();
7752 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7753 blinded_hints.push((BlindedPayInfo {
7754 fee_base_msat: *base_fee,
7755 fee_proportional_millionths: 0,
7756 htlc_minimum_msat: *htlc_min,
7757 htlc_maximum_msat: htlc_min * 100,
7758 cltv_expiry_delta: 10,
7759 features: BlindedHopFeatures::empty(),
7760 }, blinded_path.clone()));
7762 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7763 PaymentParameters::blinded(blinded_hints.clone())
7764 .with_bolt12_features(bolt12_features.clone()).unwrap()
7766 let mut route_hints = Vec::new();
7767 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7768 route_hints.push(RouteHint(vec![RouteHintHop {
7769 src_node_id: nodes[0],
7770 short_channel_id: 42 + idx as u64,
7772 base_msat: *base_fee,
7773 proportional_millionths: 0,
7775 cltv_expiry_delta: 10,
7776 htlc_minimum_msat: Some(*htlc_min),
7777 htlc_maximum_msat: Some(htlc_min * 100),
7780 PaymentParameters::from_node_id(nodes[1], 42)
7781 .with_route_hints(route_hints).unwrap()
7782 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7785 let netgraph = network_graph.read_only();
7786 let route_params = RouteParameters::from_payment_params_and_value(
7787 payment_params, amt_msat);
7789 let route = get_route(
7790 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7791 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7793 assert_eq!(route.paths.len(), 1);
7794 assert_eq!(route.get_total_amount(), amt_msat);
7798 fn candidate_path_min() {
7799 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7800 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7801 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7802 // would add a connecting first_hop node that did not have enough contribution amount, leading
7803 // to a debug panic upon invalid path construction.
7804 let secp_ctx = Secp256k1::new();
7805 let logger = Arc::new(ln_test_utils::TestLogger::new());
7806 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7807 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7808 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7809 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7810 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7811 let config = UserConfig::default();
7813 // Values are taken from the fuzz input that uncovered this panic.
7814 let amt_msat = 7_4009_8048;
7815 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7816 let first_hops = vec![get_channel_details(
7817 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7820 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7821 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7822 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7823 short_channel_id: 6,
7826 cltv_expiry_delta: (6 << 4) | 0,
7827 htlc_minimum_msat: 0,
7828 htlc_maximum_msat: MAX_VALUE_MSAT,
7830 fee_proportional_millionths: 0,
7831 excess_data: Vec::new()
7833 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7835 let htlc_min = 2_5165_8240;
7836 let blinded_hints = vec![
7838 fee_base_msat: 1_6778_3453,
7839 fee_proportional_millionths: 0,
7840 htlc_minimum_msat: htlc_min,
7841 htlc_maximum_msat: htlc_min * 100,
7842 cltv_expiry_delta: 10,
7843 features: BlindedHopFeatures::empty(),
7845 introduction_node_id: nodes[0],
7846 blinding_point: ln_test_utils::pubkey(42),
7848 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7849 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7853 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7854 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7855 .with_bolt12_features(bolt12_features.clone()).unwrap();
7856 let route_params = RouteParameters::from_payment_params_and_value(
7857 payment_params, amt_msat);
7858 let netgraph = network_graph.read_only();
7860 if let Err(LightningError { err, .. }) = get_route(
7861 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7862 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7865 assert_eq!(err, "Failed to find a path to the given destination");
7870 fn path_contribution_includes_min_htlc_overpay() {
7871 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7872 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7873 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7874 // selection, both tested here.
7875 let secp_ctx = Secp256k1::new();
7876 let logger = Arc::new(ln_test_utils::TestLogger::new());
7877 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7878 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7879 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7880 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7881 let config = UserConfig::default();
7883 // Values are taken from the fuzz input that uncovered this panic.
7884 let amt_msat = 562_0000;
7885 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7886 let first_hops = vec![
7887 get_channel_details(
7888 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7892 let htlc_mins = [49_0000, 1125_0000];
7893 let payment_params = {
7894 let blinded_path = BlindedPath {
7895 introduction_node_id: nodes[0],
7896 blinding_point: ln_test_utils::pubkey(42),
7898 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7899 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7902 let mut blinded_hints = Vec::new();
7903 for htlc_min in htlc_mins.iter() {
7904 blinded_hints.push((BlindedPayInfo {
7906 fee_proportional_millionths: 0,
7907 htlc_minimum_msat: *htlc_min,
7908 htlc_maximum_msat: *htlc_min * 100,
7909 cltv_expiry_delta: 10,
7910 features: BlindedHopFeatures::empty(),
7911 }, blinded_path.clone()));
7913 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7914 PaymentParameters::blinded(blinded_hints.clone())
7915 .with_bolt12_features(bolt12_features.clone()).unwrap()
7918 let netgraph = network_graph.read_only();
7919 let route_params = RouteParameters::from_payment_params_and_value(
7920 payment_params, amt_msat);
7921 let route = get_route(
7922 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7923 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7926 assert_eq!(route.paths.len(), 1);
7927 assert_eq!(route.get_total_amount(), amt_msat);
7931 fn first_hop_preferred_over_hint() {
7932 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
7933 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
7934 let secp_ctx = Secp256k1::new();
7935 let logger = Arc::new(ln_test_utils::TestLogger::new());
7936 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7937 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7938 let scorer = ln_test_utils::TestScorer::new();
7939 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7940 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7941 let config = UserConfig::default();
7943 let amt_msat = 1_000_000;
7944 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
7946 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
7947 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7948 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
7949 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7950 short_channel_id: 1,
7953 cltv_expiry_delta: 42,
7954 htlc_minimum_msat: 1_000,
7955 htlc_maximum_msat: 10_000_000,
7957 fee_proportional_millionths: 0,
7958 excess_data: Vec::new()
7960 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7961 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7962 short_channel_id: 1,
7965 cltv_expiry_delta: 42,
7966 htlc_minimum_msat: 1_000,
7967 htlc_maximum_msat: 10_000_000,
7969 fee_proportional_millionths: 0,
7970 excess_data: Vec::new()
7973 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7974 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
7975 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7976 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7977 short_channel_id: 2,
7980 cltv_expiry_delta: 42,
7981 htlc_minimum_msat: 1_000,
7982 htlc_maximum_msat: 10_000_000,
7984 fee_proportional_millionths: 0,
7985 excess_data: Vec::new()
7987 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7988 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7989 short_channel_id: 2,
7992 cltv_expiry_delta: 42,
7993 htlc_minimum_msat: 1_000,
7994 htlc_maximum_msat: 10_000_000,
7996 fee_proportional_millionths: 0,
7997 excess_data: Vec::new()
8000 let dest_node_id = nodes[2];
8002 let route_hint = RouteHint(vec![RouteHintHop {
8003 src_node_id: our_node_id,
8004 short_channel_id: 44,
8007 proportional_millionths: 0,
8009 cltv_expiry_delta: 10,
8010 htlc_minimum_msat: None,
8011 htlc_maximum_msat: Some(5_000_000),
8014 src_node_id: nodes[0],
8015 short_channel_id: 45,
8018 proportional_millionths: 0,
8020 cltv_expiry_delta: 10,
8021 htlc_minimum_msat: None,
8022 htlc_maximum_msat: None,
8025 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8026 .with_route_hints(vec![route_hint]).unwrap()
8027 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8028 let route_params = RouteParameters::from_payment_params_and_value(
8029 payment_params, amt_msat);
8031 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8033 let first_hop = get_channel_details(Some(1), nodes[0],
8034 channelmanager::provided_init_features(&config), 999_999);
8035 let first_hops = vec![first_hop];
8037 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8038 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8039 &Default::default(), &random_seed_bytes).unwrap();
8040 assert_eq!(route.paths.len(), 1);
8041 assert_eq!(route.get_total_amount(), amt_msat);
8042 assert_eq!(route.paths[0].hops.len(), 2);
8043 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8044 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8045 assert_eq!(route.get_total_fees(), 123);
8047 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8048 // for a first hop channel.
8049 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8050 first_hop.outbound_scid_alias = Some(44);
8051 let first_hops = vec![first_hop];
8053 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8054 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8055 &Default::default(), &random_seed_bytes);
8056 assert!(route_res.is_err());
8058 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8059 // use the cheaper second hop of the route hint.
8060 let mut first_hop = get_channel_details(Some(1), nodes[0],
8061 channelmanager::provided_init_features(&config), 10_000_000);
8062 first_hop.outbound_scid_alias = Some(44);
8063 let first_hops = vec![first_hop];
8065 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8066 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8067 &Default::default(), &random_seed_bytes).unwrap();
8068 assert_eq!(route.paths.len(), 1);
8069 assert_eq!(route.get_total_amount(), amt_msat);
8070 assert_eq!(route.paths[0].hops.len(), 2);
8071 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8072 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8073 assert_eq!(route.get_total_fees(), 123);
8077 fn allow_us_being_first_hint() {
8078 // Check that we consider a route hint even if we are the src of the first hop.
8079 let secp_ctx = Secp256k1::new();
8080 let logger = Arc::new(ln_test_utils::TestLogger::new());
8081 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8082 let scorer = ln_test_utils::TestScorer::new();
8083 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8084 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8085 let config = UserConfig::default();
8087 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8089 let amt_msat = 1_000_000;
8090 let dest_node_id = nodes[1];
8092 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8093 let first_hops = vec![first_hop];
8095 let route_hint = RouteHint(vec![RouteHintHop {
8096 src_node_id: our_node_id,
8097 short_channel_id: 44,
8100 proportional_millionths: 0,
8102 cltv_expiry_delta: 10,
8103 htlc_minimum_msat: None,
8104 htlc_maximum_msat: None,
8107 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8108 .with_route_hints(vec![route_hint]).unwrap()
8109 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8111 let route_params = RouteParameters::from_payment_params_and_value(
8112 payment_params, amt_msat);
8115 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8116 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8117 &Default::default(), &random_seed_bytes).unwrap();
8119 assert_eq!(route.paths.len(), 1);
8120 assert_eq!(route.get_total_amount(), amt_msat);
8121 assert_eq!(route.get_total_fees(), 0);
8122 assert_eq!(route.paths[0].hops.len(), 1);
8124 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8128 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
8129 pub(crate) mod bench_utils {
8133 use bitcoin::hashes::Hash;
8134 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
8136 use crate::chain::transaction::OutPoint;
8137 use crate::routing::scoring::ScoreUpdate;
8138 use crate::sign::{EntropySource, KeysManager};
8139 use crate::ln::ChannelId;
8140 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
8141 use crate::ln::features::Bolt11InvoiceFeatures;
8142 use crate::routing::gossip::NetworkGraph;
8143 use crate::util::config::UserConfig;
8144 use crate::util::ser::ReadableArgs;
8145 use crate::util::test_utils::TestLogger;
8147 /// Tries to open a network graph file, or panics with a URL to fetch it.
8148 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
8149 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
8150 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
8151 .or_else(|_| { // Fall back to guessing based on the binary location
8152 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8153 let mut path = std::env::current_exe().unwrap();
8154 path.pop(); // lightning-...
8156 path.pop(); // debug
8157 path.pop(); // target
8158 path.push("lightning");
8159 path.push("net_graph-2023-01-18.bin");
8162 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8163 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8164 let mut path = std::env::current_exe().unwrap();
8165 path.pop(); // bench...
8167 path.pop(); // debug
8168 path.pop(); // target
8169 path.pop(); // bench
8170 path.push("lightning");
8171 path.push("net_graph-2023-01-18.bin");
8174 .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");
8175 #[cfg(require_route_graph_test)]
8176 return Ok(res.unwrap());
8177 #[cfg(not(require_route_graph_test))]
8181 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
8182 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
8185 pub(crate) fn payer_pubkey() -> PublicKey {
8186 let secp_ctx = Secp256k1::new();
8187 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8191 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8193 channel_id: ChannelId::new_zero(),
8194 counterparty: ChannelCounterparty {
8195 features: channelmanager::provided_init_features(&UserConfig::default()),
8197 unspendable_punishment_reserve: 0,
8198 forwarding_info: None,
8199 outbound_htlc_minimum_msat: None,
8200 outbound_htlc_maximum_msat: None,
8202 funding_txo: Some(OutPoint {
8203 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8206 short_channel_id: Some(1),
8207 inbound_scid_alias: None,
8208 outbound_scid_alias: None,
8209 channel_value_satoshis: 10_000_000_000,
8211 balance_msat: 10_000_000_000,
8212 outbound_capacity_msat: 10_000_000_000,
8213 next_outbound_htlc_minimum_msat: 0,
8214 next_outbound_htlc_limit_msat: 10_000_000_000,
8215 inbound_capacity_msat: 0,
8216 unspendable_punishment_reserve: None,
8217 confirmations_required: None,
8218 confirmations: None,
8219 force_close_spend_delay: None,
8221 is_channel_ready: true,
8224 inbound_htlc_minimum_msat: None,
8225 inbound_htlc_maximum_msat: None,
8227 feerate_sat_per_1000_weight: None,
8228 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
8232 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8233 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8234 starting_amount: u64, route_count: usize,
8235 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8236 let payer = payer_pubkey();
8237 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8238 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8240 let nodes = graph.read_only().nodes().clone();
8241 let mut route_endpoints = Vec::new();
8242 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
8243 // with some routes we picked being un-routable.
8244 for _ in 0..route_count * 3 / 2 {
8246 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8247 let src = PublicKey::from_slice(nodes.unordered_keys()
8248 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8249 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8250 let dst = PublicKey::from_slice(nodes.unordered_keys()
8251 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8252 let params = PaymentParameters::from_node_id(dst, 42)
8253 .with_bolt11_features(features.clone()).unwrap();
8254 let first_hop = first_hop(src);
8255 let amt_msat = starting_amount + seed % 1_000_000;
8256 let route_params = RouteParameters::from_payment_params_and_value(
8257 params.clone(), amt_msat);
8259 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8260 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8262 // ...and seed the scorer with success and failure data...
8263 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8264 let mut score_amt = seed % 1_000_000_000;
8266 // Generate fail/success paths for a wider range of potential amounts with
8267 // MPP enabled to give us a chance to apply penalties for more potential
8269 let mpp_features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
8270 let params = PaymentParameters::from_node_id(dst, 42)
8271 .with_bolt11_features(mpp_features).unwrap();
8272 let route_params = RouteParameters::from_payment_params_and_value(
8273 params.clone(), score_amt);
8274 let route_res = get_route(&payer, &route_params, &graph.read_only(),
8275 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
8276 &random_seed_bytes);
8277 if let Ok(route) = route_res {
8278 for path in route.paths {
8279 if seed & 0x80 == 0 {
8280 scorer.payment_path_successful(&path);
8282 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
8283 scorer.payment_path_failed(&path, short_channel_id);
8285 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8289 // If we couldn't find a path with a higer amount, reduce and try again.
8293 route_endpoints.push((first_hop, params, amt_msat));
8299 // Because we've changed channel scores, it's possible we'll take different routes to the
8300 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
8301 // requires a too-high CLTV delta.
8302 route_endpoints.retain(|(first_hop, params, amt_msat)| {
8303 let route_params = RouteParameters::from_payment_params_and_value(
8304 params.clone(), *amt_msat);
8305 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8306 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
8308 route_endpoints.truncate(route_count);
8309 assert_eq!(route_endpoints.len(), route_count);
8317 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8318 use crate::sign::{EntropySource, KeysManager};
8319 use crate::ln::channelmanager;
8320 use crate::ln::features::Bolt11InvoiceFeatures;
8321 use crate::routing::gossip::NetworkGraph;
8322 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
8323 use crate::util::config::UserConfig;
8324 use crate::util::logger::{Logger, Record};
8325 use crate::util::test_utils::TestLogger;
8327 use criterion::Criterion;
8329 struct DummyLogger {}
8330 impl Logger for DummyLogger {
8331 fn log(&self, _record: Record) {}
8334 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8335 let logger = TestLogger::new();
8336 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8337 let scorer = FixedPenaltyScorer::with_penalty(0);
8338 generate_routes(bench, &network_graph, scorer, &Default::default(),
8339 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8342 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8343 let logger = TestLogger::new();
8344 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8345 let scorer = FixedPenaltyScorer::with_penalty(0);
8346 generate_routes(bench, &network_graph, scorer, &Default::default(),
8347 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8348 "generate_mpp_routes_with_zero_penalty_scorer");
8351 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8352 let logger = TestLogger::new();
8353 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8354 let params = ProbabilisticScoringFeeParameters::default();
8355 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8356 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8357 "generate_routes_with_probabilistic_scorer");
8360 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8361 let logger = TestLogger::new();
8362 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8363 let params = ProbabilisticScoringFeeParameters::default();
8364 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8365 generate_routes(bench, &network_graph, scorer, ¶ms,
8366 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8367 "generate_mpp_routes_with_probabilistic_scorer");
8370 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8371 let logger = TestLogger::new();
8372 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8373 let params = ProbabilisticScoringFeeParameters::default();
8374 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8375 generate_routes(bench, &network_graph, scorer, ¶ms,
8376 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8377 "generate_large_mpp_routes_with_probabilistic_scorer");
8380 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8381 let logger = TestLogger::new();
8382 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8383 let mut params = ProbabilisticScoringFeeParameters::default();
8384 params.linear_success_probability = false;
8385 let scorer = ProbabilisticScorer::new(
8386 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8387 generate_routes(bench, &network_graph, scorer, ¶ms,
8388 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8389 "generate_routes_with_nonlinear_probabilistic_scorer");
8392 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8393 let logger = TestLogger::new();
8394 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8395 let mut params = ProbabilisticScoringFeeParameters::default();
8396 params.linear_success_probability = false;
8397 let scorer = ProbabilisticScorer::new(
8398 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8399 generate_routes(bench, &network_graph, scorer, ¶ms,
8400 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8401 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8404 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8405 let logger = TestLogger::new();
8406 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8407 let mut params = ProbabilisticScoringFeeParameters::default();
8408 params.linear_success_probability = false;
8409 let scorer = ProbabilisticScorer::new(
8410 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8411 generate_routes(bench, &network_graph, scorer, ¶ms,
8412 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8413 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8416 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8417 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8418 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8419 bench_name: &'static str,
8421 let payer = bench_utils::payer_pubkey();
8422 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8423 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8425 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8426 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8428 // ...then benchmark finding paths between the nodes we learned.
8430 bench.bench_function(bench_name, |b| b.iter(|| {
8431 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8432 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8433 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8434 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());