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 #[repr(align(64))] // Force the size to 64 bytes
972 struct RouteGraphNode {
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 total_cltv_delta: u32,
982 /// The number of hops walked up to this node.
983 path_length_to_node: u8,
986 impl cmp::Ord for RouteGraphNode {
987 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
988 other.score.cmp(&self.score).then_with(|| other.node_id.cmp(&self.node_id))
992 impl cmp::PartialOrd for RouteGraphNode {
993 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
994 Some(self.cmp(other))
998 // While RouteGraphNode can be laid out with fewer bytes, performance appears to be improved
999 // substantially when it is laid out at exactly 64 bytes.
1001 // Thus, we use `#[repr(C)]` on the struct to force a suboptimal layout and check that it stays 64
1003 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1004 const _GRAPH_NODE_SMALL: usize = 64 - core::mem::size_of::<RouteGraphNode>();
1005 #[cfg(any(ldk_bench, not(any(test, fuzzing))))]
1006 const _GRAPH_NODE_FIXED_SIZE: usize = core::mem::size_of::<RouteGraphNode>() - 64;
1008 /// A wrapper around the various hop representations.
1010 /// Can be used to examine the properties of a hop,
1011 /// potentially to decide whether to include it in a route.
1012 #[derive(Clone, Debug)]
1013 pub enum CandidateRouteHop<'a> {
1014 /// A hop from the payer, where the outbound liquidity is known.
1016 /// Channel details of the first hop
1018 /// [`ChannelDetails::get_outbound_payment_scid`] MUST be `Some` (indicating the channel
1019 /// has been funded and is able to pay), and accessor methods may panic otherwise.
1021 /// [`find_route`] validates this prior to constructing a [`CandidateRouteHop`].
1022 details: &'a ChannelDetails,
1023 /// The node id of the payer, which is also the source side of this candidate route hop.
1024 payer_node_id: &'a NodeId,
1026 payer_node_counter: u32,
1028 target_node_counter: u32,
1030 /// A hop found in the [`ReadOnlyNetworkGraph`].
1032 /// Information about the channel, including potentially its capacity and
1033 /// direction-specific information.
1034 info: DirectedChannelInfo<'a>,
1035 /// The short channel ID of the channel, i.e. the identifier by which we refer to this
1037 short_channel_id: u64,
1039 /// A private hop communicated by the payee, generally via a BOLT 11 invoice.
1041 /// Because BOLT 11 route hints can take multiple hops to get to the destination, this may not
1042 /// terminate at the payee.
1044 /// Information about the private hop communicated via BOLT 11.
1045 hint: &'a RouteHintHop,
1046 /// Node id of the next hop in BOLT 11 route hint.
1047 target_node_id: &'a NodeId,
1049 source_node_counter: u32,
1051 target_node_counter: u32,
1053 /// A blinded path which starts with an introduction point and ultimately terminates with the
1056 /// Because we don't know the payee's identity, [`CandidateRouteHop::target`] will return
1057 /// `None` in this state.
1059 /// Because blinded paths are "all or nothing", and we cannot use just one part of a blinded
1060 /// path, the full path is treated as a single [`CandidateRouteHop`].
1062 /// Information about the blinded path including the fee, HTLC amount limits, and
1063 /// cryptographic material required to build an HTLC through the given path.
1064 hint: &'a (BlindedPayInfo, BlindedPath),
1065 /// Index of the hint in the original list of blinded hints.
1067 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1068 /// a short channel ID for this hop.
1071 source_node_counter: u32,
1073 /// Similar to [`Self::Blinded`], but the path here only has one hop.
1075 /// While we treat this similarly to [`CandidateRouteHop::Blinded`] in many respects (e.g.
1076 /// returning `None` from [`CandidateRouteHop::target`]), in this case we do actually know the
1077 /// payee's identity - it's the introduction point!
1079 /// [`BlindedPayInfo`] provided for 1-hop blinded paths is ignored because it is meant to apply
1080 /// to the hops *between* the introduction node and the destination.
1082 /// This primarily exists to track that we need to included a blinded path at the end of our
1083 /// [`Route`], even though it doesn't actually add an additional hop in the payment.
1085 /// Information about the blinded path including the fee, HTLC amount limits, and
1086 /// cryptographic material required to build an HTLC terminating with the given path.
1088 /// Note that the [`BlindedPayInfo`] is ignored here.
1089 hint: &'a (BlindedPayInfo, BlindedPath),
1090 /// Index of the hint in the original list of blinded hints.
1092 /// This is used to cheaply uniquely identify this blinded path, even though we don't have
1093 /// a short channel ID for this hop.
1096 source_node_counter: u32,
1100 impl<'a> CandidateRouteHop<'a> {
1101 /// Returns the short channel ID for this hop, if one is known.
1103 /// This SCID could be an alias or a globally unique SCID, and thus is only expected to
1104 /// uniquely identify this channel in conjunction with the [`CandidateRouteHop::source`].
1106 /// Returns `Some` as long as the candidate is a [`CandidateRouteHop::PublicHop`], a
1107 /// [`CandidateRouteHop::PrivateHop`] from a BOLT 11 route hint, or a
1108 /// [`CandidateRouteHop::FirstHop`] with a known [`ChannelDetails::get_outbound_payment_scid`]
1109 /// (which is always true for channels which are funded and ready for use).
1111 /// In other words, this should always return `Some` as long as the candidate hop is not a
1112 /// [`CandidateRouteHop::Blinded`] or a [`CandidateRouteHop::OneHopBlinded`].
1114 /// Note that this is deliberately not public as it is somewhat of a footgun because it doesn't
1115 /// define a global namespace.
1117 fn short_channel_id(&self) -> Option<u64> {
1119 CandidateRouteHop::FirstHop { details, .. } => details.get_outbound_payment_scid(),
1120 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1121 CandidateRouteHop::PrivateHop { hint, .. } => Some(hint.short_channel_id),
1122 CandidateRouteHop::Blinded { .. } => None,
1123 CandidateRouteHop::OneHopBlinded { .. } => None,
1127 /// Returns the globally unique short channel ID for this hop, if one is known.
1129 /// This only returns `Some` if the channel is public (either our own, or one we've learned
1130 /// from the public network graph), and thus the short channel ID we have for this channel is
1131 /// globally unique and identifies this channel in a global namespace.
1133 pub fn globally_unique_short_channel_id(&self) -> Option<u64> {
1135 CandidateRouteHop::FirstHop { details, .. } => if details.is_public { details.short_channel_id } else { None },
1136 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1137 CandidateRouteHop::PrivateHop { .. } => None,
1138 CandidateRouteHop::Blinded { .. } => None,
1139 CandidateRouteHop::OneHopBlinded { .. } => None,
1143 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1144 fn features(&self) -> ChannelFeatures {
1146 CandidateRouteHop::FirstHop { details, .. } => details.counterparty.features.to_context(),
1147 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1148 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1149 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1150 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1154 /// Returns the required difference in HTLC CLTV expiry between the [`Self::source`] and the
1155 /// next-hop for an HTLC taking this hop.
1157 /// This is the time that the node(s) in this hop have to claim the HTLC on-chain if the
1158 /// next-hop goes on chain with a payment preimage.
1160 pub fn cltv_expiry_delta(&self) -> u32 {
1162 CandidateRouteHop::FirstHop { .. } => 0,
1163 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1164 CandidateRouteHop::PrivateHop { hint, .. } => hint.cltv_expiry_delta as u32,
1165 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1166 CandidateRouteHop::OneHopBlinded { .. } => 0,
1170 /// Returns the minimum amount that can be sent over this hop, in millisatoshis.
1172 pub fn htlc_minimum_msat(&self) -> u64 {
1174 CandidateRouteHop::FirstHop { details, .. } => details.next_outbound_htlc_minimum_msat,
1175 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1176 CandidateRouteHop::PrivateHop { hint, .. } => hint.htlc_minimum_msat.unwrap_or(0),
1177 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1178 CandidateRouteHop::OneHopBlinded { .. } => 0,
1183 fn src_node_counter(&self) -> u32 {
1185 CandidateRouteHop::FirstHop { payer_node_counter, .. } => *payer_node_counter,
1186 CandidateRouteHop::PublicHop { info, .. } => info.source_counter(),
1187 CandidateRouteHop::PrivateHop { source_node_counter, .. } => *source_node_counter,
1188 CandidateRouteHop::Blinded { source_node_counter, .. } => *source_node_counter,
1189 CandidateRouteHop::OneHopBlinded { source_node_counter, .. } => *source_node_counter,
1194 fn target_node_counter(&self) -> Option<u32> {
1196 CandidateRouteHop::FirstHop { target_node_counter, .. } => Some(*target_node_counter),
1197 CandidateRouteHop::PublicHop { info, .. } => Some(info.target_counter()),
1198 CandidateRouteHop::PrivateHop { target_node_counter, .. } => Some(*target_node_counter),
1199 CandidateRouteHop::Blinded { .. } => None,
1200 CandidateRouteHop::OneHopBlinded { .. } => None,
1204 /// Returns the fees that must be paid to route an HTLC over this channel.
1206 pub fn fees(&self) -> RoutingFees {
1208 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1209 base_msat: 0, proportional_millionths: 0,
1211 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1212 CandidateRouteHop::PrivateHop { hint, .. } => hint.fees,
1213 CandidateRouteHop::Blinded { hint, .. } => {
1215 base_msat: hint.0.fee_base_msat,
1216 proportional_millionths: hint.0.fee_proportional_millionths
1219 CandidateRouteHop::OneHopBlinded { .. } =>
1220 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1224 /// Fetch the effective capacity of this hop.
1226 /// Note that this may be somewhat expensive, so calls to this should be limited and results
1228 fn effective_capacity(&self) -> EffectiveCapacity {
1230 CandidateRouteHop::FirstHop { details, .. } => EffectiveCapacity::ExactLiquidity {
1231 liquidity_msat: details.next_outbound_htlc_limit_msat,
1233 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1234 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }, .. } =>
1235 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1236 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }, .. } =>
1237 EffectiveCapacity::Infinite,
1238 CandidateRouteHop::Blinded { hint, .. } =>
1239 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1240 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1244 /// Returns an ID describing the given hop.
1246 /// See the docs on [`CandidateHopId`] for when this is, or is not, unique.
1248 fn id(&self) -> CandidateHopId {
1250 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1251 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1252 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), self.source() < self.target().unwrap())),
1255 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1257 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1263 /// Returns the source node id of current hop.
1265 /// Source node id refers to the node forwarding the HTLC through this hop.
1267 /// For [`Self::FirstHop`] we return payer's node id.
1269 pub fn source(&self) -> NodeId {
1271 CandidateRouteHop::FirstHop { payer_node_id, .. } => **payer_node_id,
1272 CandidateRouteHop::PublicHop { info, .. } => *info.source(),
1273 CandidateRouteHop::PrivateHop { hint, .. } => hint.src_node_id.into(),
1274 CandidateRouteHop::Blinded { hint, .. } => hint.1.introduction_node_id.into(),
1275 CandidateRouteHop::OneHopBlinded { hint, .. } => hint.1.introduction_node_id.into(),
1278 /// Returns the target node id of this hop, if known.
1280 /// Target node id refers to the node receiving the HTLC after this hop.
1282 /// For [`Self::Blinded`] we return `None` because the ultimate destination after the blinded
1283 /// path is unknown.
1285 /// For [`Self::OneHopBlinded`] we return `None` because the target is the same as the source,
1286 /// and such a return value would be somewhat nonsensical.
1288 pub fn target(&self) -> Option<NodeId> {
1290 CandidateRouteHop::FirstHop { details, .. } => Some(details.counterparty.node_id.into()),
1291 CandidateRouteHop::PublicHop { info, .. } => Some(*info.target()),
1292 CandidateRouteHop::PrivateHop { target_node_id, .. } => Some(**target_node_id),
1293 CandidateRouteHop::Blinded { .. } => None,
1294 CandidateRouteHop::OneHopBlinded { .. } => None,
1299 /// A unique(ish) identifier for a specific [`CandidateRouteHop`].
1301 /// For blinded paths, this ID is unique only within a given [`find_route`] call.
1303 /// For other hops, because SCIDs between private channels and public channels can conflict, this
1304 /// isn't guaranteed to be unique at all.
1306 /// For our uses, this is generally fine, but it is not public as it is otherwise a rather
1307 /// difficult-to-use API.
1308 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1309 enum CandidateHopId {
1310 /// Contains (scid, src_node_id < target_node_id)
1312 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1317 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1318 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1320 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1321 EffectiveCapacity::Infinite => u64::max_value(),
1322 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1323 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1324 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1325 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1326 // expected to have been generated from up-to-date capacity information.
1327 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1328 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1329 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1333 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1334 -> bool where I1::Item: PartialEq<I2::Item> {
1336 let a = iter_a.next();
1337 let b = iter_b.next();
1338 if a.is_none() && b.is_none() { return true; }
1339 if a.is_none() || b.is_none() { return false; }
1340 if a.unwrap().ne(&b.unwrap()) { return false; }
1344 /// It's useful to keep track of the hops associated with the fees required to use them,
1345 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1346 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1347 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1349 #[repr(C)] // Force fields to appear in the order we define them.
1350 struct PathBuildingHop<'a> {
1351 candidate: CandidateRouteHop<'a>,
1352 target_node_counter: Option<u32>,
1353 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1354 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1355 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1356 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1357 /// avoid processing them again.
1358 was_processed: bool,
1360 is_first_hop_target: bool,
1361 /// Used to compare channels when choosing the for routing.
1362 /// Includes paying for the use of a hop and the following hops, as well as
1363 /// an estimated cost of reaching this hop.
1364 /// Might get stale when fees are recomputed. Primarily for internal use.
1365 total_fee_msat: u64,
1366 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1367 /// walk and may be invalid thereafter.
1368 path_htlc_minimum_msat: u64,
1369 /// All penalties incurred from this channel on the way to the destination, as calculated using
1370 /// channel scoring.
1371 path_penalty_msat: u64,
1373 // The last 16 bytes are on the next cache line by default in glibc's malloc. Thus, we should
1374 // only place fields which are not hot there. Luckily, the next three fields are only read if
1375 // we end up on the selected path, and only in the final path layout phase, so we don't care
1376 // too much if reading them is slow.
1380 /// All the fees paid *after* this channel on the way to the destination
1381 next_hops_fee_msat: u64,
1382 /// Fee paid for the use of the current channel (see candidate.fees()).
1383 /// The value will be actually deducted from the counterparty balance on the previous link.
1384 hop_use_fee_msat: u64,
1386 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1387 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1388 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1389 // value_contribution_msat, which requires tracking it here. See comments below where it is
1390 // used for more info.
1391 value_contribution_msat: u64,
1394 // Checks that the entries in the `find_route` `dist` map fit in (exactly) two standard x86-64
1395 // cache lines. Sadly, they're not guaranteed to actually lie on a cache line (and in fact,
1396 // generally won't, because at least glibc's malloc will align to a nice, big, round
1397 // boundary...plus 16), but at least it will reduce the amount of data we'll need to load.
1399 // Note that these assertions only pass on somewhat recent rustc, and thus are gated on the
1402 const _NODE_MAP_SIZE_TWO_CACHE_LINES: usize = 128 - core::mem::size_of::<(NodeId, PathBuildingHop)>();
1404 const _NODE_MAP_SIZE_EXACTLY_CACHE_LINES: usize = core::mem::size_of::<(NodeId, PathBuildingHop)>() - 128;
1406 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1407 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1408 let mut debug_struct = f.debug_struct("PathBuildingHop");
1410 .field("source_node_id", &self.candidate.source())
1411 .field("target_node_id", &self.candidate.target())
1412 .field("short_channel_id", &self.candidate.short_channel_id())
1413 .field("total_fee_msat", &self.total_fee_msat)
1414 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1415 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1416 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat.saturating_sub(self.next_hops_fee_msat).saturating_sub(self.hop_use_fee_msat)))
1417 .field("path_penalty_msat", &self.path_penalty_msat)
1418 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1419 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1420 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1421 let debug_struct = debug_struct
1422 .field("value_contribution_msat", &self.value_contribution_msat);
1423 debug_struct.finish()
1427 // Instantiated with a list of hops with correct data in them collected during path finding,
1428 // an instance of this struct should be further modified only via given methods.
1430 struct PaymentPath<'a> {
1431 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1434 impl<'a> PaymentPath<'a> {
1435 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1436 fn get_value_msat(&self) -> u64 {
1437 self.hops.last().unwrap().0.fee_msat
1440 fn get_path_penalty_msat(&self) -> u64 {
1441 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1444 fn get_total_fee_paid_msat(&self) -> u64 {
1445 if self.hops.len() < 1 {
1449 // Can't use next_hops_fee_msat because it gets outdated.
1450 for (i, (hop, _)) in self.hops.iter().enumerate() {
1451 if i != self.hops.len() - 1 {
1452 result += hop.fee_msat;
1458 fn get_cost_msat(&self) -> u64 {
1459 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1462 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1463 // to change fees may result in an inconsistency.
1465 // Sometimes we call this function right after constructing a path which is inconsistent in
1466 // that it the value being transferred has decreased while we were doing path finding, leading
1467 // to the fees being paid not lining up with the actual limits.
1469 // Note that this function is not aware of the available_liquidity limit, and thus does not
1470 // support increasing the value being transferred beyond what was selected during the initial
1473 // Returns the amount that this path contributes to the total payment value, which may be greater
1474 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1475 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1476 let mut extra_contribution_msat = 0;
1477 let mut total_fee_paid_msat = 0 as u64;
1478 for i in (0..self.hops.len()).rev() {
1479 let last_hop = i == self.hops.len() - 1;
1481 // For non-last-hop, this value will represent the fees paid on the current hop. It
1482 // will consist of the fees for the use of the next hop, and extra fees to match
1483 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1484 let mut cur_hop_fees_msat = 0;
1486 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1489 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1490 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1491 cur_hop.path_penalty_msat += extra_contribution_msat;
1492 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1493 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1494 // set it too high just to maliciously take more fees by exploiting this
1495 // match htlc_minimum_msat logic.
1496 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1497 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1498 // Note that there is a risk that *previous hops* (those closer to us, as we go
1499 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1501 // This might make us end up with a broken route, although this should be super-rare
1502 // in practice, both because of how healthy channels look like, and how we pick
1503 // channels in add_entry.
1504 // Also, this can't be exploited more heavily than *announce a free path and fail
1506 cur_hop_transferred_amount_msat += extra_fees_msat;
1508 // We remember and return the extra fees on the final hop to allow accounting for
1509 // them in the path's value contribution.
1511 extra_contribution_msat = extra_fees_msat;
1513 total_fee_paid_msat += extra_fees_msat;
1514 cur_hop_fees_msat += extra_fees_msat;
1519 // Final hop is a special case: it usually has just value_msat (by design), but also
1520 // it still could overpay for the htlc_minimum_msat.
1521 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1523 // Propagate updated fees for the use of the channels to one hop back, where they
1524 // will be actually paid (fee_msat). The last hop is handled above separately.
1525 cur_hop.fee_msat = cur_hop_fees_msat;
1528 // Fee for the use of the current hop which will be deducted on the previous hop.
1529 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1530 // this channel is free for us.
1532 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1533 cur_hop.hop_use_fee_msat = new_fee;
1534 total_fee_paid_msat += new_fee;
1536 // It should not be possible because this function is called only to reduce the
1537 // value. In that case, compute_fee was already called with the same fees for
1538 // larger amount and there was no overflow.
1543 value_msat + extra_contribution_msat
1548 /// Calculate the fees required to route the given amount over a channel with the given fees.
1549 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1550 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1551 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1555 /// Calculate the fees required to route the given amount over a channel with the given fees,
1556 /// saturating to [`u64::max_value`].
1557 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1558 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1559 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1560 .saturating_add(channel_fees.base_msat as u64)
1563 /// The default `features` we assume for a node in a route, when no `features` are known about that
1566 /// Default features are:
1567 /// * variable_length_onion_optional
1568 fn default_node_features() -> NodeFeatures {
1569 let mut features = NodeFeatures::empty();
1570 features.set_variable_length_onion_optional();
1574 struct LoggedPayeePubkey(Option<PublicKey>);
1575 impl fmt::Display for LoggedPayeePubkey {
1576 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1579 "payee node id ".fmt(f)?;
1583 "blinded payee".fmt(f)
1589 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1590 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1591 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1593 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1594 "blinded route hint with introduction node id ".fmt(f)?;
1595 hint.1.introduction_node_id.fmt(f)?;
1596 " and blinding point ".fmt(f)?;
1597 hint.1.blinding_point.fmt(f)
1599 CandidateRouteHop::FirstHop { .. } => {
1600 "first hop with SCID ".fmt(f)?;
1601 self.0.short_channel_id().unwrap().fmt(f)
1603 CandidateRouteHop::PrivateHop { .. } => {
1604 "route hint with SCID ".fmt(f)?;
1605 self.0.short_channel_id().unwrap().fmt(f)
1609 self.0.short_channel_id().unwrap().fmt(f)
1616 fn sort_first_hop_channels(
1617 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1618 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1620 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1621 // most like to use.
1623 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1624 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1627 // Second, because simply always sorting in descending order would always use our largest
1628 // available outbound capacity, needlessly fragmenting our available channel capacities,
1629 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1630 // which have enough, but not too much, capacity for the payment.
1632 // Available outbound balances factor in liquidity already reserved for previously found paths.
1633 channels.sort_unstable_by(|chan_a, chan_b| {
1634 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1635 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1636 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1637 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1638 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1639 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1640 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1641 // Sort in descending order
1642 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1644 // Sort in ascending order
1645 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1650 /// Finds a route from us (payer) to the given target node (payee).
1652 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1653 /// in the given [`RouteParameters::payment_params`].
1654 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1656 /// Private routing paths between a public node and the target may be included in the `payee` field
1657 /// of [`RouteParameters::payment_params`].
1659 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1660 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1661 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1663 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1664 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1665 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1669 /// Panics if first_hops contains channels without `short_channel_id`s;
1670 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1672 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1673 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1674 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1675 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1676 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1677 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1678 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1679 ) -> Result<Route, LightningError>
1680 where L::Target: Logger, GL::Target: Logger {
1681 let graph_lock = network_graph.read_only();
1682 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1683 scorer, score_params, random_seed_bytes)?;
1684 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1688 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1689 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1690 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1691 _random_seed_bytes: &[u8; 32]
1692 ) -> Result<Route, LightningError>
1693 where L::Target: Logger {
1695 let payment_params = &route_params.payment_params;
1696 let final_value_msat = route_params.final_value_msat;
1697 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1698 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1699 // so use a dummy id for this in the blinded case.
1700 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1701 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1702 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1703 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1704 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1706 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1707 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1709 if our_node_id == maybe_dummy_payee_node_id {
1710 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1713 if final_value_msat > MAX_VALUE_MSAT {
1714 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1717 if final_value_msat == 0 {
1718 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1721 match &payment_params.payee {
1722 Payee::Clear { route_hints, node_id, .. } => {
1723 for route in route_hints.iter() {
1724 for hop in &route.0 {
1725 if hop.src_node_id == *node_id {
1726 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1731 Payee::Blinded { route_hints, .. } => {
1732 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1733 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});
1735 for (_, blinded_path) in route_hints.iter() {
1736 if blinded_path.blinded_hops.len() == 0 {
1737 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1738 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1739 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1740 } else if blinded_path.blinded_hops.len() == 1 &&
1741 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1742 && p.introduction_node_id != blinded_path.introduction_node_id)
1744 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1749 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1750 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1751 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});
1754 // The general routing idea is the following:
1755 // 1. Fill first/last hops communicated by the caller.
1756 // 2. Attempt to construct a path from payer to payee for transferring
1757 // any ~sufficient (described later) value.
1758 // If succeed, remember which channels were used and how much liquidity they have available,
1759 // so that future paths don't rely on the same liquidity.
1760 // 3. Proceed to the next step if:
1761 // - we hit the recommended target value;
1762 // - OR if we could not construct a new path. Any next attempt will fail too.
1763 // Otherwise, repeat step 2.
1764 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1765 // (not recommended value).
1766 // 5. If yes, proceed. If not, fail routing.
1767 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1768 // transferred up to the transfer target value.
1769 // 7. Reduce the value of the last path until we are sending only the target value.
1770 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1771 // them so that we're not sending two HTLCs along the same path.
1773 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1774 // distance from the payee
1776 // We are not a faithful Dijkstra's implementation because we can change values which impact
1777 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1778 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1779 // the value we are currently attempting to send over a path, we simply reduce the value being
1780 // sent along the path for any hops after that channel. This may imply that later fees (which
1781 // we've already tabulated) are lower because a smaller value is passing through the channels
1782 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1783 // channels which were selected earlier (and which may still be used for other paths without a
1784 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1787 // One potentially problematic case for this algorithm would be if there are many
1788 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1789 // graph walking), we may never find a path which is not liquidity-limited and has lower
1790 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1791 // Because we only consider paths with at least 5% of the total value being sent, the damage
1792 // from such a case should be limited, however this could be further reduced in the future by
1793 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1794 // limits for the purposes of fee calculation.
1796 // Alternatively, we could store more detailed path information in the heap (targets, below)
1797 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1798 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1799 // and practically (as we would need to store dynamically-allocated path information in heap
1800 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1801 // results of such an algorithm would likely be biased towards lower-value paths.
1803 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1804 // outside of our current search value, running a path search more times to gather candidate
1805 // paths at different values. While this may be acceptable, further path searches may increase
1806 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1807 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1808 // the same time, remaining generic across different payment values.
1810 let network_channels = network_graph.channels();
1811 let network_nodes = network_graph.nodes();
1813 if payment_params.max_path_count == 0 {
1814 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1817 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1818 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1820 let allow_mpp = if payment_params.max_path_count == 1 {
1822 } else if payment_params.payee.supports_basic_mpp() {
1824 } else if let Some(payee) = payee_node_id_opt {
1825 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1826 |info| info.features.supports_basic_mpp()))
1829 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1831 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1832 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1833 if allow_mpp { "with" } else { "without" },
1834 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1835 max_total_routing_fee_msat);
1837 let private_hop_targets_node_counter_offset = network_graph.max_node_counter() + 2;
1838 let mut private_node_id_to_node_counter = HashMap::new();
1840 let mut private_hop_key_cache = HashMap::with_capacity(
1841 payment_params.payee.unblinded_route_hints().iter().map(|path| path.0.len()).sum()
1844 // Because we store references to private hop node_ids in `dist`, below, we need them to exist
1845 // (as `NodeId`, not `PublicKey`) for the lifetime of `dist`. Thus, we calculate all the keys
1846 // we'll need here and simply fetch them when routing.
1847 let payee_node_counter = payee_node_id_opt
1848 .and_then(|payee| network_nodes.get(&payee))
1849 .map(|node| node.node_counter)
1850 .unwrap_or(private_hop_targets_node_counter_offset);
1851 private_node_id_to_node_counter.insert(maybe_dummy_payee_node_id, payee_node_counter);
1852 private_hop_key_cache.insert(maybe_dummy_payee_pk, (NodeId::from_pubkey(&maybe_dummy_payee_pk), payee_node_counter));
1854 for route in payment_params.payee.unblinded_route_hints().iter() {
1855 for hop in route.0.iter() {
1856 let hop_node_id = NodeId::from_pubkey(&hop.src_node_id);
1857 let node_counter = if let Some(node) = network_nodes.get(&hop_node_id) {
1860 let next_node_counter = private_hop_targets_node_counter_offset + private_node_id_to_node_counter.len() as u32;
1861 *private_node_id_to_node_counter.entry(hop_node_id)
1862 .or_insert(next_node_counter)
1864 private_hop_key_cache.insert(hop.src_node_id, (hop_node_id, node_counter));
1869 // Prepare the data we'll use for payee-to-payer search by
1870 // inserting first hops suggested by the caller as targets.
1871 // Our search will then attempt to reach them while traversing from the payee node.
1872 let mut first_hop_targets: HashMap<_, (Vec<&ChannelDetails>, u32)> =
1873 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1874 if let Some(hops) = first_hops {
1876 if chan.get_outbound_payment_scid().is_none() {
1877 panic!("first_hops should be filled in with usable channels, not pending ones");
1879 if chan.counterparty.node_id == *our_node_pubkey {
1880 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1882 let counterparty_node_id = NodeId::from_pubkey(&chan.counterparty.node_id);
1884 .entry(counterparty_node_id)
1885 .or_insert_with(|| {
1886 let node_counter = if let Some(node) = network_nodes.get(&counterparty_node_id) {
1889 let next_node_counter = private_hop_targets_node_counter_offset + private_node_id_to_node_counter.len() as u32;
1890 *private_node_id_to_node_counter.entry(counterparty_node_id)
1891 .or_insert(next_node_counter)
1893 (Vec::new(), node_counter)
1897 if first_hop_targets.is_empty() {
1898 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1902 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1903 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1904 // adding duplicate entries when we find a better path to a given node.
1905 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1907 // Map from node_id to information about the best current path to that node, including feerate
1909 let dist_len = private_hop_targets_node_counter_offset + private_hop_key_cache.len() as u32 + 1;
1910 let mut dist: Vec<Option<PathBuildingHop>> = vec![None; dist_len as usize];
1911 let payer_node_counter = network_nodes
1913 .map(|node| node.node_counter)
1915 private_node_id_to_node_counter.get(&our_node_id).map(|counter| *counter)
1917 .unwrap_or(network_graph.max_node_counter() + 1);
1919 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1920 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1921 // htlc_minimum with extra fees while still finding a cheaper path.
1922 let mut hit_minimum_limit;
1924 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1925 // We start with a path_value of the exact amount we want, and if that generates a route we may
1926 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1927 // amount we want in total across paths, selecting the best subset at the end.
1928 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1929 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1930 let mut path_value_msat = final_value_msat;
1932 // Routing Fragmentation Mitigation heuristic:
1934 // Routing fragmentation across many payment paths increases the overall routing
1935 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1936 // Taking too many smaller paths also increases the chance of payment failure.
1937 // Thus to avoid this effect, we require from our collected links to provide
1938 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1939 // This requirement is currently set to be 1/max_path_count of the payment
1940 // value to ensure we only ever return routes that do not violate this limit.
1941 let minimal_value_contribution_msat: u64 = if allow_mpp {
1942 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1947 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1948 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1949 // drop the requirement by setting this to 0.
1950 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1952 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1953 // determine if the channel can be used by additional MPP paths or to inform path finding
1954 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1955 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1957 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1958 HashMap::with_capacity(network_nodes.len());
1960 // Keeping track of how much value we already collected across other paths. Helps to decide
1961 // when we want to stop looking for new paths.
1962 let mut already_collected_value_msat = 0;
1964 for (_, (channels, _)) in first_hop_targets.iter_mut() {
1965 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1969 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1970 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1972 // Remember how many candidates we ignored to allow for some logging afterwards.
1973 let mut num_ignored_value_contribution: u32 = 0;
1974 let mut num_ignored_path_length_limit: u32 = 0;
1975 let mut num_ignored_cltv_delta_limit: u32 = 0;
1976 let mut num_ignored_previously_failed: u32 = 0;
1977 let mut num_ignored_total_fee_limit: u32 = 0;
1978 let mut num_ignored_avoid_overpayment: u32 = 0;
1979 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
1981 macro_rules! add_entry {
1982 // Adds entry which goes from $candidate.source() to $candidate.target() over the $candidate hop.
1983 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1984 // since that value has to be transferred over this channel.
1985 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1986 ( $candidate: expr, $next_hops_fee_msat: expr,
1987 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1988 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1989 // We "return" whether we updated the path at the end, and how much we can route via
1990 // this channel, via this:
1991 let mut hop_contribution_amt_msat = None;
1992 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1993 // practice these cases should be caught earlier:
1994 // - for regular channels at channel announcement (TODO)
1995 // - for first and last hops early in get_route
1996 let src_node_id = $candidate.source();
1997 if Some(src_node_id) != $candidate.target() {
1998 let scid_opt = $candidate.short_channel_id();
1999 let effective_capacity = $candidate.effective_capacity();
2000 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
2002 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
2003 // It may be misleading because we might later choose to reduce the value transferred
2004 // over these channels, and the channel which was insufficient might become sufficient.
2005 // Worst case: we drop a good channel here because it can't cover the high following
2006 // fees caused by one expensive channel, but then this channel could have been used
2007 // if the amount being transferred over this path is lower.
2008 // We do this for now, but this is a subject for removal.
2009 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
2010 let used_liquidity_msat = used_liquidities
2011 .get(&$candidate.id())
2012 .map_or(0, |used_liquidity_msat| {
2013 available_value_contribution_msat = available_value_contribution_msat
2014 .saturating_sub(*used_liquidity_msat);
2015 *used_liquidity_msat
2018 // Verify the liquidity offered by this channel complies to the minimal contribution.
2019 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
2020 // Do not consider candidate hops that would exceed the maximum path length.
2021 let path_length_to_node = $next_hops_path_length + 1;
2022 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
2024 // Do not consider candidates that exceed the maximum total cltv expiry limit.
2025 // In order to already account for some of the privacy enhancing random CLTV
2026 // expiry delta offset we add on top later, we subtract a rough estimate
2027 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
2028 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
2029 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
2030 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
2031 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
2032 .saturating_add($candidate.cltv_expiry_delta());
2033 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
2035 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
2036 // Includes paying fees for the use of the following channels.
2037 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
2038 Some(result) => result,
2039 // Can't overflow due to how the values were computed right above.
2040 None => unreachable!(),
2042 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2043 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
2044 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
2046 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
2047 let may_overpay_to_meet_path_minimum_msat =
2048 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
2049 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
2050 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
2051 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
2053 let payment_failed_on_this_channel = scid_opt.map_or(false,
2054 |scid| payment_params.previously_failed_channels.contains(&scid));
2056 let (should_log_candidate, first_hop_details) = match $candidate {
2057 CandidateRouteHop::FirstHop { details, .. } => (true, Some(details)),
2058 CandidateRouteHop::PrivateHop { .. } => (true, None),
2059 CandidateRouteHop::Blinded { .. } => (true, None),
2060 CandidateRouteHop::OneHopBlinded { .. } => (true, None),
2064 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
2065 // bother considering this channel. If retrying with recommended_value_msat may
2066 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
2067 // around again with a higher amount.
2068 if !contributes_sufficient_value {
2069 if should_log_candidate {
2070 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
2072 if let Some(details) = first_hop_details {
2074 "First hop candidate next_outbound_htlc_limit_msat: {}",
2075 details.next_outbound_htlc_limit_msat,
2079 num_ignored_value_contribution += 1;
2080 } else if exceeds_max_path_length {
2081 if should_log_candidate {
2082 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
2084 num_ignored_path_length_limit += 1;
2085 } else if exceeds_cltv_delta_limit {
2086 if should_log_candidate {
2087 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
2089 if let Some(_) = first_hop_details {
2091 "First hop candidate cltv_expiry_delta: {}. Limit: {}",
2092 hop_total_cltv_delta,
2093 max_total_cltv_expiry_delta,
2097 num_ignored_cltv_delta_limit += 1;
2098 } else if payment_failed_on_this_channel {
2099 if should_log_candidate {
2100 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
2102 num_ignored_previously_failed += 1;
2103 } else if may_overpay_to_meet_path_minimum_msat {
2104 if should_log_candidate {
2106 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
2107 LoggedCandidateHop(&$candidate));
2109 if let Some(details) = first_hop_details {
2111 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2112 details.next_outbound_htlc_minimum_msat,
2116 num_ignored_avoid_overpayment += 1;
2117 hit_minimum_limit = true;
2118 } else if over_path_minimum_msat {
2119 // Note that low contribution here (limited by available_liquidity_msat)
2120 // might violate htlc_minimum_msat on the hops which are next along the
2121 // payment path (upstream to the payee). To avoid that, we recompute
2122 // path fees knowing the final path contribution after constructing it.
2123 let curr_min = cmp::max(
2124 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
2126 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
2127 .saturating_add(curr_min);
2129 let dist_entry = &mut dist[$candidate.src_node_counter() as usize];
2130 let old_entry = if let Some(hop) = dist_entry {
2133 // If there was previously no known way to access the source node
2134 // (recall it goes payee-to-payer) of short_channel_id, first add a
2135 // semi-dummy record just to compute the fees to reach the source node.
2136 // This will affect our decision on selecting short_channel_id
2137 // as a way to reach the $candidate.target() node.
2138 *dist_entry = Some(PathBuildingHop {
2139 candidate: $candidate.clone(),
2140 target_node_counter: None,
2142 next_hops_fee_msat: u64::max_value(),
2143 hop_use_fee_msat: u64::max_value(),
2144 total_fee_msat: u64::max_value(),
2145 path_htlc_minimum_msat,
2146 path_penalty_msat: u64::max_value(),
2147 was_processed: false,
2148 is_first_hop_target: false,
2149 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2150 value_contribution_msat,
2152 dist_entry.as_mut().unwrap()
2155 #[allow(unused_mut)] // We only use the mut in cfg(test)
2156 let mut should_process = !old_entry.was_processed;
2157 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2159 // In test/fuzzing builds, we do extra checks to make sure the skipping
2160 // of already-seen nodes only happens in cases we expect (see below).
2161 if !should_process { should_process = true; }
2165 let mut hop_use_fee_msat = 0;
2166 let mut total_fee_msat: u64 = $next_hops_fee_msat;
2168 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
2169 // will have the same effective-fee
2170 if src_node_id != our_node_id {
2171 // Note that `u64::max_value` means we'll always fail the
2172 // `old_entry.total_fee_msat > total_fee_msat` check below
2173 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
2174 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
2177 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
2178 if total_fee_msat > max_total_routing_fee_msat {
2179 if should_log_candidate {
2180 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
2182 if let Some(_) = first_hop_details {
2184 "First hop candidate routing fee: {}. Limit: {}",
2186 max_total_routing_fee_msat,
2190 num_ignored_total_fee_limit += 1;
2192 let channel_usage = ChannelUsage {
2193 amount_msat: amount_to_transfer_over_msat,
2194 inflight_htlc_msat: used_liquidity_msat,
2197 let channel_penalty_msat =
2198 scorer.channel_penalty_msat($candidate,
2201 let path_penalty_msat = $next_hops_path_penalty_msat
2202 .saturating_add(channel_penalty_msat);
2204 // Update the way of reaching $candidate.source()
2205 // with the given short_channel_id (from $candidate.target()),
2206 // if this way is cheaper than the already known
2207 // (considering the cost to "reach" this channel from the route destination,
2208 // the cost of using this channel,
2209 // and the cost of routing to the source node of this channel).
2210 // Also, consider that htlc_minimum_msat_difference, because we might end up
2211 // paying it. Consider the following exploit:
2212 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
2213 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
2214 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
2215 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
2217 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
2218 // but it may require additional tracking - we don't want to double-count
2219 // the fees included in $next_hops_path_htlc_minimum_msat, but also
2220 // can't use something that may decrease on future hops.
2221 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
2222 .saturating_add(old_entry.path_penalty_msat);
2223 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
2224 .saturating_add(path_penalty_msat);
2226 if !old_entry.was_processed && new_cost < old_cost {
2227 let new_graph_node = RouteGraphNode {
2228 node_id: src_node_id,
2229 score: cmp::max(total_fee_msat, path_htlc_minimum_msat).saturating_add(path_penalty_msat),
2230 total_cltv_delta: hop_total_cltv_delta,
2231 value_contribution_msat,
2232 path_length_to_node,
2234 targets.push(new_graph_node);
2235 old_entry.target_node_counter = $candidate.target_node_counter();
2236 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
2237 old_entry.hop_use_fee_msat = hop_use_fee_msat;
2238 old_entry.total_fee_msat = total_fee_msat;
2239 old_entry.candidate = $candidate.clone();
2240 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
2241 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
2242 old_entry.path_penalty_msat = path_penalty_msat;
2243 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2245 old_entry.value_contribution_msat = value_contribution_msat;
2247 hop_contribution_amt_msat = Some(value_contribution_msat);
2248 } else if old_entry.was_processed && new_cost < old_cost {
2249 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2251 // If we're skipping processing a node which was previously
2252 // processed even though we found another path to it with a
2253 // cheaper fee, check that it was because the second path we
2254 // found (which we are processing now) has a lower value
2255 // contribution due to an HTLC minimum limit.
2257 // e.g. take a graph with two paths from node 1 to node 2, one
2258 // through channel A, and one through channel B. Channel A and
2259 // B are both in the to-process heap, with their scores set by
2260 // a higher htlc_minimum than fee.
2261 // Channel A is processed first, and the channels onwards from
2262 // node 1 are added to the to-process heap. Thereafter, we pop
2263 // Channel B off of the heap, note that it has a much more
2264 // restrictive htlc_maximum_msat, and recalculate the fees for
2265 // all of node 1's channels using the new, reduced, amount.
2267 // This would be bogus - we'd be selecting a higher-fee path
2268 // with a lower htlc_maximum_msat instead of the one we'd
2269 // already decided to use.
2270 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
2272 value_contribution_msat + path_penalty_msat <
2273 old_entry.value_contribution_msat + old_entry.path_penalty_msat
2280 if should_log_candidate {
2282 "Ignoring {} due to its htlc_minimum_msat limit.",
2283 LoggedCandidateHop(&$candidate));
2285 if let Some(details) = first_hop_details {
2287 "First hop candidate next_outbound_htlc_minimum_msat: {}",
2288 details.next_outbound_htlc_minimum_msat,
2292 num_ignored_htlc_minimum_msat_limit += 1;
2296 hop_contribution_amt_msat
2300 let default_node_features = default_node_features();
2302 // Find ways (channels with destination) to reach a given node and store them
2303 // in the corresponding data structures (routing graph etc).
2304 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2305 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2306 // This data can later be helpful to optimize routing (pay lower fees).
2307 macro_rules! add_entries_to_cheapest_to_target_node {
2308 ( $node: expr, $node_id: expr, $next_hops_value_contribution: expr,
2309 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2310 let fee_to_target_msat;
2311 let next_hops_path_htlc_minimum_msat;
2312 let next_hops_path_penalty_msat;
2313 let is_first_hop_target;
2314 let skip_node = if let Some(elem) = &mut dist[$node.node_counter as usize] {
2315 let was_processed = elem.was_processed;
2316 elem.was_processed = true;
2317 fee_to_target_msat = elem.total_fee_msat;
2318 next_hops_path_htlc_minimum_msat = elem.path_htlc_minimum_msat;
2319 next_hops_path_penalty_msat = elem.path_penalty_msat;
2320 is_first_hop_target = elem.is_first_hop_target;
2323 // Entries are added to dist in add_entry!() when there is a channel from a node.
2324 // Because there are no channels from payee, it will not have a dist entry at this point.
2325 // If we're processing any other node, it is always be the result of a channel from it.
2326 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2328 fee_to_target_msat = 0;
2329 next_hops_path_htlc_minimum_msat = 0;
2330 next_hops_path_penalty_msat = 0;
2331 is_first_hop_target = false;
2336 if is_first_hop_target {
2337 if let Some((first_channels, peer_node_counter)) = first_hop_targets.get(&$node_id) {
2338 for details in first_channels {
2339 debug_assert_eq!(*peer_node_counter, $node.node_counter);
2340 let candidate = CandidateRouteHop::FirstHop {
2341 details, payer_node_id: &our_node_id, payer_node_counter,
2342 target_node_counter: $node.node_counter,
2344 add_entry!(&candidate, fee_to_target_msat,
2345 $next_hops_value_contribution,
2346 next_hops_path_htlc_minimum_msat, next_hops_path_penalty_msat,
2347 $next_hops_cltv_delta, $next_hops_path_length);
2352 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2355 &default_node_features
2358 if !features.requires_unknown_bits() {
2359 for chan_id in $node.channels.iter() {
2360 let chan = network_channels.get(chan_id).unwrap();
2361 if !chan.features.requires_unknown_bits() {
2362 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2363 if first_hops.is_none() || *source != our_node_id {
2364 if directed_channel.direction().enabled {
2365 let candidate = CandidateRouteHop::PublicHop {
2366 info: directed_channel,
2367 short_channel_id: *chan_id,
2369 add_entry!(&candidate,
2371 $next_hops_value_contribution,
2372 next_hops_path_htlc_minimum_msat,
2373 next_hops_path_penalty_msat,
2374 $next_hops_cltv_delta, $next_hops_path_length);
2385 let mut payment_paths = Vec::<PaymentPath>::new();
2387 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2388 'paths_collection: loop {
2389 // For every new path, start from scratch, except for used_liquidities, which
2390 // helps to avoid reusing previously selected paths in future iterations.
2392 for e in dist.iter_mut() {
2395 for (node_id, (chans, peer_node_counter)) in first_hop_targets.iter() {
2396 // In order to avoid looking up whether each node is a first-hop target, we store a
2397 // dummy entry in dist for each first-hop target, allowing us to do this lookup for
2398 // free since we're already looking at the `was_processed` flag.
2400 // Note that all the fields (except `is_first_hop_target`) will be overwritten whenever
2401 // we find a path to the target, so are left as dummies here.
2402 dist[*peer_node_counter as usize] = Some(PathBuildingHop {
2403 candidate: CandidateRouteHop::FirstHop {
2405 payer_node_id: &our_node_id,
2406 target_node_counter: u32::max_value(),
2407 payer_node_counter: u32::max_value(),
2409 target_node_counter: None,
2411 next_hops_fee_msat: u64::max_value(),
2412 hop_use_fee_msat: u64::max_value(),
2413 total_fee_msat: u64::max_value(),
2414 path_htlc_minimum_msat: u64::max_value(),
2415 path_penalty_msat: u64::max_value(),
2416 was_processed: false,
2417 is_first_hop_target: true,
2418 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
2419 value_contribution_msat: 0,
2422 hit_minimum_limit = false;
2424 // If first hop is a private channel and the only way to reach the payee, this is the only
2425 // place where it could be added.
2426 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|(first_channels, peer_node_counter)| {
2427 debug_assert_eq!(*peer_node_counter, payee_node_counter);
2428 for details in first_channels {
2429 let candidate = CandidateRouteHop::FirstHop {
2430 details, payer_node_id: &our_node_id, payer_node_counter,
2431 target_node_counter: payee_node_counter,
2433 let added = add_entry!(&candidate, 0, path_value_msat,
2434 0, 0u64, 0, 0).is_some();
2435 log_trace!(logger, "{} direct route to payee via {}",
2436 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2440 // Add the payee as a target, so that the payee-to-payer
2441 // search algorithm knows what to start with.
2442 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2443 // The payee is not in our network graph, so nothing to add here.
2444 // There is still a chance of reaching them via last_hops though,
2445 // so don't yet fail the payment here.
2446 // If not, targets.pop() will not even let us enter the loop in step 2.
2449 add_entries_to_cheapest_to_target_node!(node, payee, path_value_msat, 0, 0);
2454 // If a caller provided us with last hops, add them to routing targets. Since this happens
2455 // earlier than general path finding, they will be somewhat prioritized, although currently
2456 // it matters only if the fees are exactly the same.
2457 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2458 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2459 let intro_node_counter_opt =
2460 // Only add the hops in this route to our candidate set if either
2461 // we have a direct channel to the first hop or the first hop is
2462 // in the regular network graph.
2463 network_nodes.get(&intro_node_id).map(|node| node.node_counter)
2465 first_hop_targets.get(&intro_node_id).map(|(_, node_counter)| *node_counter)
2467 if intro_node_counter_opt.is_none() || our_node_id == intro_node_id { continue }
2468 let candidate = if hint.1.blinded_hops.len() == 1 {
2469 CandidateRouteHop::OneHopBlinded {
2472 source_node_counter: intro_node_counter_opt.unwrap(),
2475 CandidateRouteHop::Blinded {
2478 source_node_counter: intro_node_counter_opt.unwrap(),
2481 let mut path_contribution_msat = path_value_msat;
2482 if let Some(hop_used_msat) = add_entry!(&candidate,
2483 0, path_contribution_msat, 0, 0_u64, 0, 0)
2485 path_contribution_msat = hop_used_msat;
2487 if let Some((first_channels, peer_node_counter)) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2488 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2490 for details in first_channels {
2491 let first_hop_candidate = CandidateRouteHop::FirstHop {
2492 details, payer_node_id: &our_node_id, payer_node_counter,
2493 target_node_counter: *peer_node_counter,
2495 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2499 let path_min = candidate.htlc_minimum_msat().saturating_add(
2500 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2501 add_entry!(&first_hop_candidate, blinded_path_fee,
2502 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2503 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2507 for route in payment_params.payee.unblinded_route_hints().iter()
2508 .filter(|route| !route.0.is_empty())
2510 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2511 let first_hop_src_is_reachable =
2512 // Only add the hops in this route to our candidate set if either we are part of
2513 // the first hop, we have a direct channel to the first hop, or the first hop is in
2514 // the regular network graph.
2515 our_node_id == first_hop_src_id ||
2516 first_hop_targets.get(&first_hop_src_id).is_some() ||
2517 network_nodes.get(&first_hop_src_id).is_some();
2518 if first_hop_src_is_reachable {
2519 // We start building the path from reverse, i.e., from payee
2520 // to the first RouteHintHop in the path.
2521 let hop_iter = route.0.iter().rev();
2522 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2523 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2524 let mut hop_used = true;
2525 let mut aggregate_next_hops_fee_msat: u64 = 0;
2526 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2527 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2528 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2529 let mut aggregate_next_hops_path_length: u8 = 0;
2530 let mut aggregate_path_contribution_msat = path_value_msat;
2532 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2533 let (target, private_target_node_counter) = private_hop_key_cache.get(&prev_hop_id).unwrap();
2534 let (_src_id, private_source_node_counter) = private_hop_key_cache.get(&hop.src_node_id).unwrap();
2536 if let Some((first_channels, _)) = first_hop_targets.get(&target) {
2537 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2538 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2539 hop.short_channel_id);
2544 let candidate = network_channels
2545 .get(&hop.short_channel_id)
2546 .and_then(|channel| channel.as_directed_to(&target))
2547 .map(|(info, _)| CandidateRouteHop::PublicHop {
2549 short_channel_id: hop.short_channel_id,
2551 .unwrap_or_else(|| CandidateRouteHop::PrivateHop {
2552 hint: hop, target_node_id: target,
2553 source_node_counter: *private_source_node_counter,
2554 target_node_counter: *private_target_node_counter,
2557 if let Some(hop_used_msat) = add_entry!(&candidate,
2558 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2559 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2560 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2562 aggregate_path_contribution_msat = hop_used_msat;
2564 // If this hop was not used then there is no use checking the preceding
2565 // hops in the RouteHint. We can break by just searching for a direct
2566 // channel between last checked hop and first_hop_targets.
2570 let used_liquidity_msat = used_liquidities
2571 .get(&candidate.id()).copied()
2573 let channel_usage = ChannelUsage {
2574 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2575 inflight_htlc_msat: used_liquidity_msat,
2576 effective_capacity: candidate.effective_capacity(),
2578 let channel_penalty_msat = scorer.channel_penalty_msat(
2579 &candidate, channel_usage, score_params
2581 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2582 .saturating_add(channel_penalty_msat);
2584 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2585 .saturating_add(hop.cltv_expiry_delta as u32);
2587 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2590 // Searching for a direct channel between last checked hop and first_hop_targets
2591 if let Some((first_channels, peer_node_counter)) = first_hop_targets.get_mut(&target) {
2592 sort_first_hop_channels(first_channels, &used_liquidities,
2593 recommended_value_msat, our_node_pubkey);
2594 for details in first_channels {
2595 let first_hop_candidate = CandidateRouteHop::FirstHop {
2596 details, payer_node_id: &our_node_id, payer_node_counter,
2597 target_node_counter: *peer_node_counter,
2599 add_entry!(&first_hop_candidate,
2600 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2601 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2602 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2610 // In the next values of the iterator, the aggregate fees already reflects
2611 // the sum of value sent from payer (final_value_msat) and routing fees
2612 // for the last node in the RouteHint. We need to just add the fees to
2613 // route through the current node so that the preceding node (next iteration)
2615 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2616 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2617 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2619 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2620 // this route hint's source node to forward said min over this channel.
2621 aggregate_next_hops_path_htlc_minimum_msat = {
2622 let curr_htlc_min = cmp::max(
2623 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2625 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2626 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2629 if idx == route.0.len() - 1 {
2630 // The last hop in this iterator is the first hop in
2631 // overall RouteHint.
2632 // If this hop connects to a node with which we have a direct channel,
2633 // ignore the network graph and, if the last hop was added, add our
2634 // direct channel to the candidate set.
2636 // Note that we *must* check if the last hop was added as `add_entry`
2637 // always assumes that the third argument is a node to which we have a
2639 if let Some((first_channels, peer_node_counter)) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2640 sort_first_hop_channels(first_channels, &used_liquidities,
2641 recommended_value_msat, our_node_pubkey);
2642 for details in first_channels {
2643 let first_hop_candidate = CandidateRouteHop::FirstHop {
2644 details, payer_node_id: &our_node_id, payer_node_counter,
2645 target_node_counter: *peer_node_counter,
2647 add_entry!(&first_hop_candidate,
2648 aggregate_next_hops_fee_msat,
2649 aggregate_path_contribution_msat,
2650 aggregate_next_hops_path_htlc_minimum_msat,
2651 aggregate_next_hops_path_penalty_msat,
2652 aggregate_next_hops_cltv_delta,
2653 aggregate_next_hops_path_length);
2661 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2663 // At this point, targets are filled with the data from first and
2664 // last hops communicated by the caller, and the payment receiver.
2665 let mut found_new_path = false;
2668 // If this loop terminates due the exhaustion of targets, two situations are possible:
2669 // - not enough outgoing liquidity:
2670 // 0 < already_collected_value_msat < final_value_msat
2671 // - enough outgoing liquidity:
2672 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2673 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2674 // paths_collection will be stopped because found_new_path==false.
2675 // This is not necessarily a routing failure.
2676 'path_construction: while let Some(RouteGraphNode { node_id, total_cltv_delta, mut value_contribution_msat, path_length_to_node, .. }) = targets.pop() {
2678 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2679 // traversing the graph and arrange the path out of what we found.
2680 if node_id == our_node_id {
2681 let mut new_entry = dist[payer_node_counter as usize].take().unwrap();
2682 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2685 let mut features_set = false;
2686 let candidate = &ordered_hops.last().unwrap().0.candidate;
2687 let target = candidate.target().unwrap_or(maybe_dummy_payee_node_id);
2688 let target_node_counter = candidate.target_node_counter();
2689 if let Some((first_channels, _)) = first_hop_targets.get(&target) {
2690 for details in first_channels {
2691 if let CandidateRouteHop::FirstHop { details: last_hop_details, .. }
2692 = ordered_hops.last().unwrap().0.candidate
2694 if details.get_outbound_payment_scid() == last_hop_details.get_outbound_payment_scid() {
2695 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2696 features_set = true;
2703 if let Some(node) = network_nodes.get(&target) {
2704 if let Some(node_info) = node.announcement_info.as_ref() {
2705 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2707 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2710 // We can fill in features for everything except hops which were
2711 // provided via the invoice we're paying. We could guess based on the
2712 // recipient's features but for now we simply avoid guessing at all.
2716 // Means we succesfully traversed from the payer to the payee, now
2717 // save this path for the payment route. Also, update the liquidity
2718 // remaining on the used hops, so that we take them into account
2719 // while looking for more paths.
2720 if target_node_counter.is_none() {
2723 if target_node_counter == Some(payee_node_counter) { break 'path_walk; }
2725 new_entry = match dist[target_node_counter.unwrap() as usize].take() {
2726 Some(payment_hop) => payment_hop,
2727 // We can't arrive at None because, if we ever add an entry to targets,
2728 // we also fill in the entry in dist (see add_entry!).
2729 None => unreachable!(),
2731 // We "propagate" the fees one hop backward (topologically) here,
2732 // so that fees paid for a HTLC forwarding on the current channel are
2733 // associated with the previous channel (where they will be subtracted).
2734 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2735 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2737 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2738 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2740 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2741 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2743 let mut payment_path = PaymentPath {hops: ordered_hops};
2745 // We could have possibly constructed a slightly inconsistent path: since we reduce
2746 // value being transferred along the way, we could have violated htlc_minimum_msat
2747 // on some channels we already passed (assuming dest->source direction). Here, we
2748 // recompute the fees again, so that if that's the case, we match the currently
2749 // underpaid htlc_minimum_msat with fees.
2750 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2751 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2752 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2754 // Since a path allows to transfer as much value as
2755 // the smallest channel it has ("bottleneck"), we should recompute
2756 // the fees so sender HTLC don't overpay fees when traversing
2757 // larger channels than the bottleneck. This may happen because
2758 // when we were selecting those channels we were not aware how much value
2759 // this path will transfer, and the relative fee for them
2760 // might have been computed considering a larger value.
2761 // Remember that we used these channels so that we don't rely
2762 // on the same liquidity in future paths.
2763 let mut prevented_redundant_path_selection = false;
2764 for (hop, _) in payment_path.hops.iter() {
2765 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2766 let used_liquidity_msat = used_liquidities
2767 .entry(hop.candidate.id())
2768 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2769 .or_insert(spent_on_hop_msat);
2770 let hop_capacity = hop.candidate.effective_capacity();
2771 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2772 if *used_liquidity_msat == hop_max_msat {
2773 // If this path used all of this channel's available liquidity, we know
2774 // this path will not be selected again in the next loop iteration.
2775 prevented_redundant_path_selection = true;
2777 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2779 if !prevented_redundant_path_selection {
2780 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2781 // we'll probably end up picking the same path again on the next iteration.
2782 // Decrease the available liquidity of a hop in the middle of the path.
2783 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2784 let exhausted = u64::max_value();
2786 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2787 LoggedCandidateHop(victim_candidate));
2788 if let Some(scid) = victim_candidate.short_channel_id() {
2789 *used_liquidities.entry(CandidateHopId::Clear((scid, false))).or_default() = exhausted;
2790 *used_liquidities.entry(CandidateHopId::Clear((scid, true))).or_default() = exhausted;
2794 // Track the total amount all our collected paths allow to send so that we know
2795 // when to stop looking for more paths
2796 already_collected_value_msat += value_contribution_msat;
2798 payment_paths.push(payment_path);
2799 found_new_path = true;
2800 break 'path_construction;
2803 // If we found a path back to the payee, we shouldn't try to process it again. This is
2804 // the equivalent of the `elem.was_processed` check in
2805 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2806 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2808 // Otherwise, since the current target node is not us,
2809 // keep "unrolling" the payment graph from payee to payer by
2810 // finding a way to reach the current target from the payer side.
2811 match network_nodes.get(&node_id) {
2814 add_entries_to_cheapest_to_target_node!(node, node_id,
2815 value_contribution_msat,
2816 total_cltv_delta, path_length_to_node);
2822 if !found_new_path && channel_saturation_pow_half != 0 {
2823 channel_saturation_pow_half = 0;
2824 continue 'paths_collection;
2826 // If we don't support MPP, no use trying to gather more value ever.
2827 break 'paths_collection;
2831 // Stop either when the recommended value is reached or if no new path was found in this
2833 // In the latter case, making another path finding attempt won't help,
2834 // because we deterministically terminated the search due to low liquidity.
2835 if !found_new_path && channel_saturation_pow_half != 0 {
2836 channel_saturation_pow_half = 0;
2837 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2838 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2839 path_value_msat = recommended_value_msat;
2840 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2841 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2842 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2843 break 'paths_collection;
2844 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2845 // Further, if this was our first walk of the graph, and we weren't limited by an
2846 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2847 // limited by an htlc_minimum_msat value, find another path with a higher value,
2848 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2849 // still keeping a lower total fee than this path.
2850 if !hit_minimum_limit {
2851 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2852 break 'paths_collection;
2854 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.");
2855 path_value_msat = recommended_value_msat;
2859 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2860 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2861 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2862 num_ignored_total_fee_limit;
2863 if num_ignored_total > 0 {
2865 "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.",
2866 num_ignored_value_contribution, num_ignored_path_length_limit,
2867 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2868 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2869 num_ignored_total_fee_limit, num_ignored_total);
2873 if payment_paths.len() == 0 {
2874 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2877 if already_collected_value_msat < final_value_msat {
2878 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2882 let mut selected_route = payment_paths;
2884 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2885 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2887 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2888 // the value they contribute towards the payment amount.
2889 // We sort in descending order as we will remove from the front in `retain`, next.
2890 selected_route.sort_unstable_by(|a, b|
2891 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2892 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2895 // We should make sure that at least 1 path left.
2896 let mut paths_left = selected_route.len();
2897 selected_route.retain(|path| {
2898 if paths_left == 1 {
2901 let path_value_msat = path.get_value_msat();
2902 if path_value_msat <= overpaid_value_msat {
2903 overpaid_value_msat -= path_value_msat;
2909 debug_assert!(selected_route.len() > 0);
2911 if overpaid_value_msat != 0 {
2913 // Now, subtract the remaining overpaid value from the most-expensive path.
2914 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2915 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2916 selected_route.sort_unstable_by(|a, b| {
2917 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2918 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2919 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2921 let expensive_payment_path = selected_route.first_mut().unwrap();
2923 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2924 // can't go negative.
2925 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2926 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2930 // Sort by the path itself and combine redundant paths.
2931 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2932 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2934 selected_route.sort_unstable_by_key(|path| {
2935 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2936 debug_assert!(path.hops.len() <= key.len());
2937 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id()).zip(key.iter_mut()) {
2942 for idx in 0..(selected_route.len() - 1) {
2943 if idx + 1 >= selected_route.len() { break; }
2944 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target())),
2945 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(), h.0.candidate.target()))) {
2946 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2947 selected_route[idx].update_value_and_recompute_fees(new_value);
2948 selected_route.remove(idx + 1);
2952 let mut paths = Vec::new();
2953 for payment_path in selected_route {
2954 let mut hops = Vec::with_capacity(payment_path.hops.len());
2955 for (hop, node_features) in payment_path.hops.iter()
2956 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2958 let target = hop.candidate.target().expect("target is defined when short_channel_id is defined");
2959 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2960 // If we sourced the hop from the graph we're sure the target node is announced.
2962 } else if let CandidateRouteHop::FirstHop { details, .. } = hop.candidate {
2963 // If this is a first hop we also know if it's announced.
2966 // If we sourced it any other way, we double-check the network graph to see if
2967 // there are announced channels between the endpoints. If so, the hop might be
2968 // referring to any of the announced channels, as its `short_channel_id` might be
2969 // an alias, in which case we don't take any chances here.
2970 network_graph.node(&target).map_or(false, |hop_node|
2971 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2972 .map_or(false, |c| c.as_directed_from(&hop.candidate.source()).is_some()))
2976 hops.push(RouteHop {
2977 pubkey: PublicKey::from_slice(target.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &target), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2978 node_features: node_features.clone(),
2979 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2980 channel_features: hop.candidate.features(),
2981 fee_msat: hop.fee_msat,
2982 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2983 maybe_announced_channel,
2986 let mut final_cltv_delta = final_cltv_expiry_delta;
2987 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2988 if let Some(blinded_path) = h.candidate.blinded_path() {
2989 final_cltv_delta = h.candidate.cltv_expiry_delta();
2991 hops: blinded_path.blinded_hops.clone(),
2992 blinding_point: blinded_path.blinding_point,
2993 excess_final_cltv_expiry_delta: 0,
2994 final_value_msat: h.fee_msat,
2998 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2999 // applicable for the previous hop.
3000 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
3001 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
3004 paths.push(Path { hops, blinded_tail });
3006 // Make sure we would never create a route with more paths than we allow.
3007 debug_assert!(paths.len() <= payment_params.max_path_count.into());
3009 if let Some(node_features) = payment_params.payee.node_features() {
3010 for path in paths.iter_mut() {
3011 path.hops.last_mut().unwrap().node_features = node_features.clone();
3015 let route = Route { paths, route_params: Some(route_params.clone()) };
3017 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
3018 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
3019 if route.get_total_fees() > max_total_routing_fee_msat {
3020 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
3021 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
3025 log_info!(logger, "Got route: {}", log_route!(route));
3029 // When an adversarial intermediary node observes a payment, it may be able to infer its
3030 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
3031 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
3032 // payment path by adding a randomized 'shadow route' offset to the final hop.
3033 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
3034 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
3036 let network_channels = network_graph.channels();
3037 let network_nodes = network_graph.nodes();
3039 for path in route.paths.iter_mut() {
3040 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
3042 // Remember the last three nodes of the random walk and avoid looping back on them.
3043 // Init with the last three nodes from the actual path, if possible.
3044 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
3045 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
3046 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
3048 // Choose the last publicly known node as the starting point for the random walk.
3049 let mut cur_hop: Option<NodeId> = None;
3050 let mut path_nonce = [0u8; 12];
3051 if let Some(starting_hop) = path.hops.iter().rev()
3052 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
3053 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
3054 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
3057 // Init PRNG with the path-dependant nonce, which is static for private paths.
3058 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
3059 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
3061 // Pick a random path length in [1 .. 3]
3062 prng.process_in_place(&mut random_path_bytes);
3063 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
3065 for random_hop in 0..random_walk_length {
3066 // If we don't find a suitable offset in the public network graph, we default to
3067 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3068 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
3070 if let Some(cur_node_id) = cur_hop {
3071 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
3072 // Randomly choose the next unvisited hop.
3073 prng.process_in_place(&mut random_path_bytes);
3074 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
3075 .checked_rem(cur_node.channels.len())
3076 .and_then(|index| cur_node.channels.get(index))
3077 .and_then(|id| network_channels.get(id)) {
3078 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
3079 if !nodes_to_avoid.iter().any(|x| x == next_id) {
3080 nodes_to_avoid[random_hop] = *next_id;
3081 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
3082 cur_hop = Some(*next_id);
3089 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
3090 .checked_add(random_hop_offset)
3091 .unwrap_or(shadow_ctlv_expiry_delta_offset);
3094 // Limit the total offset to reduce the worst-case locked liquidity timevalue
3095 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
3096 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
3098 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
3099 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
3100 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
3101 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
3102 max_path_offset = cmp::max(
3103 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
3104 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
3105 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
3107 // Add 'shadow' CLTV offset to the final hop
3108 if let Some(tail) = path.blinded_tail.as_mut() {
3109 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
3110 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
3112 if let Some(last_hop) = path.hops.last_mut() {
3113 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
3114 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
3119 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
3120 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
3122 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
3123 pub fn build_route_from_hops<L: Deref, GL: Deref>(
3124 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3125 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
3126 ) -> Result<Route, LightningError>
3127 where L::Target: Logger, GL::Target: Logger {
3128 let graph_lock = network_graph.read_only();
3129 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
3130 &graph_lock, logger, random_seed_bytes)?;
3131 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
3135 fn build_route_from_hops_internal<L: Deref>(
3136 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
3137 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
3138 ) -> Result<Route, LightningError> where L::Target: Logger {
3141 our_node_id: NodeId,
3142 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
3145 impl ScoreLookUp for HopScorer {
3146 type ScoreParams = ();
3147 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop,
3148 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
3150 let mut cur_id = self.our_node_id;
3151 for i in 0..self.hop_ids.len() {
3152 if let Some(next_id) = self.hop_ids[i] {
3153 if cur_id == candidate.source() && Some(next_id) == candidate.target() {
3165 impl<'a> Writeable for HopScorer {
3167 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
3172 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
3173 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
3176 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
3177 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
3178 for i in 0..hops.len() {
3179 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
3182 let scorer = HopScorer { our_node_id, hop_ids };
3184 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
3189 use crate::blinded_path::{BlindedHop, BlindedPath};
3190 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
3191 use crate::routing::utxo::UtxoResult;
3192 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
3193 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
3194 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters, CandidateRouteHop};
3195 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
3196 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
3197 use crate::chain::transaction::OutPoint;
3198 use crate::sign::EntropySource;
3199 use crate::ln::ChannelId;
3200 use crate::ln::features::{BlindedHopFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
3201 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
3202 use crate::ln::channelmanager;
3203 use crate::offers::invoice::BlindedPayInfo;
3204 use crate::util::config::UserConfig;
3205 use crate::util::test_utils as ln_test_utils;
3206 use crate::util::chacha20::ChaCha20;
3207 use crate::util::ser::{Readable, Writeable};
3209 use crate::util::ser::Writer;
3211 use bitcoin::hashes::Hash;
3212 use bitcoin::network::constants::Network;
3213 use bitcoin::blockdata::constants::ChainHash;
3214 use bitcoin::blockdata::script::Builder;
3215 use bitcoin::blockdata::opcodes;
3216 use bitcoin::blockdata::transaction::TxOut;
3217 use bitcoin::hashes::hex::FromHex;
3218 use bitcoin::secp256k1::{PublicKey,SecretKey};
3219 use bitcoin::secp256k1::Secp256k1;
3221 use crate::io::Cursor;
3222 use crate::prelude::*;
3223 use crate::sync::Arc;
3225 use core::convert::TryInto;
3227 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
3228 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
3229 channelmanager::ChannelDetails {
3230 channel_id: ChannelId::new_zero(),
3231 counterparty: channelmanager::ChannelCounterparty {
3234 unspendable_punishment_reserve: 0,
3235 forwarding_info: None,
3236 outbound_htlc_minimum_msat: None,
3237 outbound_htlc_maximum_msat: None,
3239 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
3242 outbound_scid_alias: None,
3243 inbound_scid_alias: None,
3244 channel_value_satoshis: 0,
3247 outbound_capacity_msat,
3248 next_outbound_htlc_limit_msat: outbound_capacity_msat,
3249 next_outbound_htlc_minimum_msat: 0,
3250 inbound_capacity_msat: 42,
3251 unspendable_punishment_reserve: None,
3252 confirmations_required: None,
3253 confirmations: None,
3254 force_close_spend_delay: None,
3255 is_outbound: true, is_channel_ready: true,
3256 is_usable: true, is_public: true,
3257 inbound_htlc_minimum_msat: None,
3258 inbound_htlc_maximum_msat: None,
3260 feerate_sat_per_1000_weight: None,
3261 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
3266 fn simple_route_test() {
3267 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3268 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3269 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3270 let scorer = ln_test_utils::TestScorer::new();
3271 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3272 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3274 // Simple route to 2 via 1
3276 let route_params = RouteParameters::from_payment_params_and_value(
3277 payment_params.clone(), 0);
3278 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3279 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3280 &Default::default(), &random_seed_bytes) {
3281 assert_eq!(err, "Cannot send a payment of 0 msat");
3282 } else { panic!(); }
3284 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3285 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3286 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3287 assert_eq!(route.paths[0].hops.len(), 2);
3289 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3290 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3291 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3292 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3293 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3294 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3296 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3297 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3298 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3299 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3300 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3301 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3305 fn invalid_first_hop_test() {
3306 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3307 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3308 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3309 let scorer = ln_test_utils::TestScorer::new();
3310 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3311 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3313 // Simple route to 2 via 1
3315 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
3317 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3318 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3319 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
3320 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
3321 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
3322 } else { panic!(); }
3324 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3325 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3326 assert_eq!(route.paths[0].hops.len(), 2);
3330 fn htlc_minimum_test() {
3331 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3332 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3333 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3334 let scorer = ln_test_utils::TestScorer::new();
3335 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3336 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3338 // Simple route to 2 via 1
3340 // Disable other paths
3341 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3342 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3343 short_channel_id: 12,
3345 flags: 2, // to disable
3346 cltv_expiry_delta: 0,
3347 htlc_minimum_msat: 0,
3348 htlc_maximum_msat: MAX_VALUE_MSAT,
3350 fee_proportional_millionths: 0,
3351 excess_data: Vec::new()
3353 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3354 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3355 short_channel_id: 3,
3357 flags: 2, // to disable
3358 cltv_expiry_delta: 0,
3359 htlc_minimum_msat: 0,
3360 htlc_maximum_msat: MAX_VALUE_MSAT,
3362 fee_proportional_millionths: 0,
3363 excess_data: Vec::new()
3365 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3366 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3367 short_channel_id: 13,
3369 flags: 2, // to disable
3370 cltv_expiry_delta: 0,
3371 htlc_minimum_msat: 0,
3372 htlc_maximum_msat: MAX_VALUE_MSAT,
3374 fee_proportional_millionths: 0,
3375 excess_data: Vec::new()
3377 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3378 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3379 short_channel_id: 6,
3381 flags: 2, // to disable
3382 cltv_expiry_delta: 0,
3383 htlc_minimum_msat: 0,
3384 htlc_maximum_msat: MAX_VALUE_MSAT,
3386 fee_proportional_millionths: 0,
3387 excess_data: Vec::new()
3389 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3390 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3391 short_channel_id: 7,
3393 flags: 2, // to disable
3394 cltv_expiry_delta: 0,
3395 htlc_minimum_msat: 0,
3396 htlc_maximum_msat: MAX_VALUE_MSAT,
3398 fee_proportional_millionths: 0,
3399 excess_data: Vec::new()
3402 // Check against amount_to_transfer_over_msat.
3403 // Set minimal HTLC of 200_000_000 msat.
3404 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3405 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3406 short_channel_id: 2,
3409 cltv_expiry_delta: 0,
3410 htlc_minimum_msat: 200_000_000,
3411 htlc_maximum_msat: MAX_VALUE_MSAT,
3413 fee_proportional_millionths: 0,
3414 excess_data: Vec::new()
3417 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3419 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3420 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3421 short_channel_id: 4,
3424 cltv_expiry_delta: 0,
3425 htlc_minimum_msat: 0,
3426 htlc_maximum_msat: 199_999_999,
3428 fee_proportional_millionths: 0,
3429 excess_data: Vec::new()
3432 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3433 let route_params = RouteParameters::from_payment_params_and_value(
3434 payment_params, 199_999_999);
3435 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3436 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3437 &Default::default(), &random_seed_bytes) {
3438 assert_eq!(err, "Failed to find a path to the given destination");
3439 } else { panic!(); }
3441 // Lift the restriction on the first hop.
3442 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3443 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3444 short_channel_id: 2,
3447 cltv_expiry_delta: 0,
3448 htlc_minimum_msat: 0,
3449 htlc_maximum_msat: MAX_VALUE_MSAT,
3451 fee_proportional_millionths: 0,
3452 excess_data: Vec::new()
3455 // A payment above the minimum should pass
3456 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3457 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3458 assert_eq!(route.paths[0].hops.len(), 2);
3462 fn htlc_minimum_overpay_test() {
3463 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3464 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3465 let config = UserConfig::default();
3466 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
3467 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
3469 let scorer = ln_test_utils::TestScorer::new();
3470 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3471 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3473 // A route to node#2 via two paths.
3474 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3475 // Thus, they can't send 60 without overpaying.
3476 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3477 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3478 short_channel_id: 2,
3481 cltv_expiry_delta: 0,
3482 htlc_minimum_msat: 35_000,
3483 htlc_maximum_msat: 40_000,
3485 fee_proportional_millionths: 0,
3486 excess_data: Vec::new()
3488 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3489 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3490 short_channel_id: 12,
3493 cltv_expiry_delta: 0,
3494 htlc_minimum_msat: 35_000,
3495 htlc_maximum_msat: 40_000,
3497 fee_proportional_millionths: 0,
3498 excess_data: Vec::new()
3502 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3503 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3504 short_channel_id: 13,
3507 cltv_expiry_delta: 0,
3508 htlc_minimum_msat: 0,
3509 htlc_maximum_msat: MAX_VALUE_MSAT,
3511 fee_proportional_millionths: 0,
3512 excess_data: Vec::new()
3514 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3515 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3516 short_channel_id: 4,
3519 cltv_expiry_delta: 0,
3520 htlc_minimum_msat: 0,
3521 htlc_maximum_msat: MAX_VALUE_MSAT,
3523 fee_proportional_millionths: 0,
3524 excess_data: Vec::new()
3527 // Disable other paths
3528 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3529 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3530 short_channel_id: 1,
3532 flags: 2, // to disable
3533 cltv_expiry_delta: 0,
3534 htlc_minimum_msat: 0,
3535 htlc_maximum_msat: MAX_VALUE_MSAT,
3537 fee_proportional_millionths: 0,
3538 excess_data: Vec::new()
3541 let mut route_params = RouteParameters::from_payment_params_and_value(
3542 payment_params.clone(), 60_000);
3543 route_params.max_total_routing_fee_msat = Some(15_000);
3544 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3545 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3546 // Overpay fees to hit htlc_minimum_msat.
3547 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3548 // TODO: this could be better balanced to overpay 10k and not 15k.
3549 assert_eq!(overpaid_fees, 15_000);
3551 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3552 // while taking even more fee to match htlc_minimum_msat.
3553 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3554 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3555 short_channel_id: 12,
3558 cltv_expiry_delta: 0,
3559 htlc_minimum_msat: 65_000,
3560 htlc_maximum_msat: 80_000,
3562 fee_proportional_millionths: 0,
3563 excess_data: Vec::new()
3565 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3566 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3567 short_channel_id: 2,
3570 cltv_expiry_delta: 0,
3571 htlc_minimum_msat: 0,
3572 htlc_maximum_msat: MAX_VALUE_MSAT,
3574 fee_proportional_millionths: 0,
3575 excess_data: Vec::new()
3577 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3578 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3579 short_channel_id: 4,
3582 cltv_expiry_delta: 0,
3583 htlc_minimum_msat: 0,
3584 htlc_maximum_msat: MAX_VALUE_MSAT,
3586 fee_proportional_millionths: 100_000,
3587 excess_data: Vec::new()
3590 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3591 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3592 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3593 assert_eq!(route.paths.len(), 1);
3594 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3595 let fees = route.paths[0].hops[0].fee_msat;
3596 assert_eq!(fees, 5_000);
3598 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3599 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3600 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3601 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3602 // the other channel.
3603 assert_eq!(route.paths.len(), 1);
3604 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3605 let fees = route.paths[0].hops[0].fee_msat;
3606 assert_eq!(fees, 5_000);
3610 fn htlc_minimum_recipient_overpay_test() {
3611 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3612 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3613 let config = UserConfig::default();
3614 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
3615 let scorer = ln_test_utils::TestScorer::new();
3616 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3617 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3619 // Route to node2 over a single path which requires overpaying the recipient themselves.
3621 // First disable all paths except the us -> node1 -> node2 path
3622 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3623 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3624 short_channel_id: 13,
3627 cltv_expiry_delta: 0,
3628 htlc_minimum_msat: 0,
3629 htlc_maximum_msat: 0,
3631 fee_proportional_millionths: 0,
3632 excess_data: Vec::new()
3635 // Set channel 4 to free but with a high htlc_minimum_msat
3636 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3637 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3638 short_channel_id: 4,
3641 cltv_expiry_delta: 0,
3642 htlc_minimum_msat: 15_000,
3643 htlc_maximum_msat: MAX_VALUE_MSAT,
3645 fee_proportional_millionths: 0,
3646 excess_data: Vec::new()
3649 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3650 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3651 // what we try to find a route for, so this test only just happens to work out to exactly
3653 let mut route_params = RouteParameters::from_payment_params_and_value(
3654 payment_params.clone(), 5_000);
3655 route_params.max_total_routing_fee_msat = Some(9_999);
3656 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3657 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3658 &Default::default(), &random_seed_bytes) {
3659 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3660 } else { panic!(); }
3662 let mut route_params = RouteParameters::from_payment_params_and_value(
3663 payment_params.clone(), 5_000);
3664 route_params.max_total_routing_fee_msat = Some(10_000);
3665 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3666 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3667 assert_eq!(route.get_total_fees(), 10_000);
3671 fn disable_channels_test() {
3672 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3673 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3674 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3675 let scorer = ln_test_utils::TestScorer::new();
3676 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3677 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3679 // // Disable channels 4 and 12 by flags=2
3680 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3681 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3682 short_channel_id: 4,
3684 flags: 2, // to disable
3685 cltv_expiry_delta: 0,
3686 htlc_minimum_msat: 0,
3687 htlc_maximum_msat: MAX_VALUE_MSAT,
3689 fee_proportional_millionths: 0,
3690 excess_data: Vec::new()
3692 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3693 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
3694 short_channel_id: 12,
3696 flags: 2, // to disable
3697 cltv_expiry_delta: 0,
3698 htlc_minimum_msat: 0,
3699 htlc_maximum_msat: MAX_VALUE_MSAT,
3701 fee_proportional_millionths: 0,
3702 excess_data: Vec::new()
3705 // If all the channels require some features we don't understand, route should fail
3706 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3707 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3708 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3709 &Default::default(), &random_seed_bytes) {
3710 assert_eq!(err, "Failed to find a path to the given destination");
3711 } else { panic!(); }
3713 // If we specify a channel to node7, that overrides our local channel view and that gets used
3714 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3715 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3716 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3717 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3718 &Default::default(), &random_seed_bytes).unwrap();
3719 assert_eq!(route.paths[0].hops.len(), 2);
3721 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3722 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3723 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3724 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3725 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3726 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3728 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3729 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3730 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3731 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3732 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3733 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3737 fn disable_node_test() {
3738 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3739 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3740 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3741 let scorer = ln_test_utils::TestScorer::new();
3742 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3743 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3745 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3746 let mut unknown_features = NodeFeatures::empty();
3747 unknown_features.set_unknown_feature_required();
3748 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3749 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3750 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3752 // If all nodes require some features we don't understand, route should fail
3753 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3754 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3755 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3756 &Default::default(), &random_seed_bytes) {
3757 assert_eq!(err, "Failed to find a path to the given destination");
3758 } else { panic!(); }
3760 // If we specify a channel to node7, that overrides our local channel view and that gets used
3761 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3762 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3763 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3764 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3765 &Default::default(), &random_seed_bytes).unwrap();
3766 assert_eq!(route.paths[0].hops.len(), 2);
3768 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3769 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3770 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3771 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3772 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3773 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3775 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3776 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3777 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3778 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3779 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3780 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3782 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3783 // naively) assume that the user checked the feature bits on the invoice, which override
3784 // the node_announcement.
3788 fn our_chans_test() {
3789 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3790 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3791 let scorer = ln_test_utils::TestScorer::new();
3792 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3793 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3795 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3796 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3797 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3798 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3799 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3800 assert_eq!(route.paths[0].hops.len(), 3);
3802 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3803 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3804 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3805 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3806 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3807 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3809 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3810 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3811 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3812 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3813 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3814 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3816 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3817 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3818 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3819 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3820 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3821 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3823 // If we specify a channel to node7, that overrides our local channel view and that gets used
3824 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3825 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3826 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3827 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3828 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3829 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3830 &Default::default(), &random_seed_bytes).unwrap();
3831 assert_eq!(route.paths[0].hops.len(), 2);
3833 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3834 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3835 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3836 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3837 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3838 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3840 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3841 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3842 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3843 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3844 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3845 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3848 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3849 let zero_fees = RoutingFees {
3851 proportional_millionths: 0,
3853 vec![RouteHint(vec![RouteHintHop {
3854 src_node_id: nodes[3],
3855 short_channel_id: 8,
3857 cltv_expiry_delta: (8 << 4) | 1,
3858 htlc_minimum_msat: None,
3859 htlc_maximum_msat: None,
3861 ]), RouteHint(vec![RouteHintHop {
3862 src_node_id: nodes[4],
3863 short_channel_id: 9,
3866 proportional_millionths: 0,
3868 cltv_expiry_delta: (9 << 4) | 1,
3869 htlc_minimum_msat: None,
3870 htlc_maximum_msat: None,
3871 }]), RouteHint(vec![RouteHintHop {
3872 src_node_id: nodes[5],
3873 short_channel_id: 10,
3875 cltv_expiry_delta: (10 << 4) | 1,
3876 htlc_minimum_msat: None,
3877 htlc_maximum_msat: None,
3881 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3882 let zero_fees = RoutingFees {
3884 proportional_millionths: 0,
3886 vec![RouteHint(vec![RouteHintHop {
3887 src_node_id: nodes[2],
3888 short_channel_id: 5,
3891 proportional_millionths: 0,
3893 cltv_expiry_delta: (5 << 4) | 1,
3894 htlc_minimum_msat: None,
3895 htlc_maximum_msat: None,
3897 src_node_id: nodes[3],
3898 short_channel_id: 8,
3900 cltv_expiry_delta: (8 << 4) | 1,
3901 htlc_minimum_msat: None,
3902 htlc_maximum_msat: None,
3904 ]), RouteHint(vec![RouteHintHop {
3905 src_node_id: nodes[4],
3906 short_channel_id: 9,
3909 proportional_millionths: 0,
3911 cltv_expiry_delta: (9 << 4) | 1,
3912 htlc_minimum_msat: None,
3913 htlc_maximum_msat: None,
3914 }]), RouteHint(vec![RouteHintHop {
3915 src_node_id: nodes[5],
3916 short_channel_id: 10,
3918 cltv_expiry_delta: (10 << 4) | 1,
3919 htlc_minimum_msat: None,
3920 htlc_maximum_msat: None,
3925 fn partial_route_hint_test() {
3926 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3927 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3928 let scorer = ln_test_utils::TestScorer::new();
3929 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3930 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3932 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3933 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3934 // RouteHint may be partially used by the algo to build the best path.
3936 // First check that last hop can't have its source as the payee.
3937 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3938 src_node_id: nodes[6],
3939 short_channel_id: 8,
3942 proportional_millionths: 0,
3944 cltv_expiry_delta: (8 << 4) | 1,
3945 htlc_minimum_msat: None,
3946 htlc_maximum_msat: None,
3949 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3950 invalid_last_hops.push(invalid_last_hop);
3952 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3953 .with_route_hints(invalid_last_hops).unwrap();
3954 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3955 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3956 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3957 &Default::default(), &random_seed_bytes) {
3958 assert_eq!(err, "Route hint cannot have the payee as the source.");
3959 } else { panic!(); }
3962 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3963 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3964 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3965 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3966 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3967 assert_eq!(route.paths[0].hops.len(), 5);
3969 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3970 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3971 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3972 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3973 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3974 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3976 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3977 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3978 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3979 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3980 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3981 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3983 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3984 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3985 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3986 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3987 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3988 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3990 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3991 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3992 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3993 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3994 // If we have a peer in the node map, we'll use their features here since we don't have
3995 // a way of figuring out their features from the invoice:
3996 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3997 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3999 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4000 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4001 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4002 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4003 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4004 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4007 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4008 let zero_fees = RoutingFees {
4010 proportional_millionths: 0,
4012 vec![RouteHint(vec![RouteHintHop {
4013 src_node_id: nodes[3],
4014 short_channel_id: 8,
4016 cltv_expiry_delta: (8 << 4) | 1,
4017 htlc_minimum_msat: None,
4018 htlc_maximum_msat: None,
4019 }]), RouteHint(vec![
4021 ]), RouteHint(vec![RouteHintHop {
4022 src_node_id: nodes[5],
4023 short_channel_id: 10,
4025 cltv_expiry_delta: (10 << 4) | 1,
4026 htlc_minimum_msat: None,
4027 htlc_maximum_msat: None,
4032 fn ignores_empty_last_hops_test() {
4033 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4034 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4035 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
4036 let scorer = ln_test_utils::TestScorer::new();
4037 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4038 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4040 // Test handling of an empty RouteHint passed in Invoice.
4041 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4042 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4043 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4044 assert_eq!(route.paths[0].hops.len(), 5);
4046 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4047 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4048 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4049 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4050 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4051 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4053 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4054 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4055 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4056 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4057 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4058 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4060 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4061 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4062 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4063 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4064 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4065 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4067 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4068 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4069 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4070 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4071 // If we have a peer in the node map, we'll use their features here since we don't have
4072 // a way of figuring out their features from the invoice:
4073 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4074 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4076 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4077 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4078 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4079 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4080 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4081 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4084 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
4086 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
4087 let zero_fees = RoutingFees {
4089 proportional_millionths: 0,
4091 vec![RouteHint(vec![RouteHintHop {
4092 src_node_id: hint_hops[0],
4093 short_channel_id: 0xff00,
4096 proportional_millionths: 0,
4098 cltv_expiry_delta: (5 << 4) | 1,
4099 htlc_minimum_msat: None,
4100 htlc_maximum_msat: None,
4102 src_node_id: hint_hops[1],
4103 short_channel_id: 0xff01,
4105 cltv_expiry_delta: (8 << 4) | 1,
4106 htlc_minimum_msat: None,
4107 htlc_maximum_msat: None,
4112 fn multi_hint_last_hops_test() {
4113 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4114 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4115 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
4116 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4117 let scorer = ln_test_utils::TestScorer::new();
4118 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4119 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4120 // Test through channels 2, 3, 0xff00, 0xff01.
4121 // Test shows that multiple hop hints are considered.
4123 // Disabling channels 6 & 7 by flags=2
4124 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4125 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4126 short_channel_id: 6,
4128 flags: 2, // to disable
4129 cltv_expiry_delta: 0,
4130 htlc_minimum_msat: 0,
4131 htlc_maximum_msat: MAX_VALUE_MSAT,
4133 fee_proportional_millionths: 0,
4134 excess_data: Vec::new()
4136 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4137 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4138 short_channel_id: 7,
4140 flags: 2, // to disable
4141 cltv_expiry_delta: 0,
4142 htlc_minimum_msat: 0,
4143 htlc_maximum_msat: MAX_VALUE_MSAT,
4145 fee_proportional_millionths: 0,
4146 excess_data: Vec::new()
4149 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4150 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4151 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4152 assert_eq!(route.paths[0].hops.len(), 4);
4154 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4155 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4156 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4157 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4158 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4159 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4161 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4162 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4163 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4164 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4165 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4166 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4168 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
4169 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4170 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4171 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4172 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
4173 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4175 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4176 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4177 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4178 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4179 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4180 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4184 fn private_multi_hint_last_hops_test() {
4185 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4186 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4188 let non_announced_privkey = SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
4189 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
4191 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
4192 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
4193 let scorer = ln_test_utils::TestScorer::new();
4194 // Test through channels 2, 3, 0xff00, 0xff01.
4195 // Test shows that multiple hop hints are considered.
4197 // Disabling channels 6 & 7 by flags=2
4198 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4199 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4200 short_channel_id: 6,
4202 flags: 2, // to disable
4203 cltv_expiry_delta: 0,
4204 htlc_minimum_msat: 0,
4205 htlc_maximum_msat: MAX_VALUE_MSAT,
4207 fee_proportional_millionths: 0,
4208 excess_data: Vec::new()
4210 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4211 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4212 short_channel_id: 7,
4214 flags: 2, // to disable
4215 cltv_expiry_delta: 0,
4216 htlc_minimum_msat: 0,
4217 htlc_maximum_msat: MAX_VALUE_MSAT,
4219 fee_proportional_millionths: 0,
4220 excess_data: Vec::new()
4223 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4224 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4225 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
4226 assert_eq!(route.paths[0].hops.len(), 4);
4228 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4229 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4230 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
4231 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
4232 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4233 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4235 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4236 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4237 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4238 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
4239 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4240 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4242 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
4243 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
4244 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4245 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
4246 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4247 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4249 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4250 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
4251 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4252 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4253 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4254 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4257 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
4258 let zero_fees = RoutingFees {
4260 proportional_millionths: 0,
4262 vec![RouteHint(vec![RouteHintHop {
4263 src_node_id: nodes[4],
4264 short_channel_id: 11,
4266 cltv_expiry_delta: (11 << 4) | 1,
4267 htlc_minimum_msat: None,
4268 htlc_maximum_msat: None,
4270 src_node_id: nodes[3],
4271 short_channel_id: 8,
4273 cltv_expiry_delta: (8 << 4) | 1,
4274 htlc_minimum_msat: None,
4275 htlc_maximum_msat: None,
4276 }]), RouteHint(vec![RouteHintHop {
4277 src_node_id: nodes[4],
4278 short_channel_id: 9,
4281 proportional_millionths: 0,
4283 cltv_expiry_delta: (9 << 4) | 1,
4284 htlc_minimum_msat: None,
4285 htlc_maximum_msat: None,
4286 }]), RouteHint(vec![RouteHintHop {
4287 src_node_id: nodes[5],
4288 short_channel_id: 10,
4290 cltv_expiry_delta: (10 << 4) | 1,
4291 htlc_minimum_msat: None,
4292 htlc_maximum_msat: None,
4297 fn last_hops_with_public_channel_test() {
4298 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4299 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4300 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
4301 let scorer = ln_test_utils::TestScorer::new();
4302 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4303 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4304 // This test shows that public routes can be present in the invoice
4305 // which would be handled in the same manner.
4307 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4308 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4309 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4310 assert_eq!(route.paths[0].hops.len(), 5);
4312 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4313 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4314 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
4315 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4316 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4317 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4319 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4320 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4321 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4322 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4323 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4324 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4326 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4327 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4328 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4329 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4330 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4331 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4333 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4334 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4335 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
4336 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4337 // If we have a peer in the node map, we'll use their features here since we don't have
4338 // a way of figuring out their features from the invoice:
4339 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4340 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4342 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4343 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4344 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
4345 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4346 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4347 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4351 fn our_chans_last_hop_connect_test() {
4352 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4353 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4354 let scorer = ln_test_utils::TestScorer::new();
4355 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4356 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4358 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
4359 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
4360 let mut last_hops = last_hops(&nodes);
4361 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4362 .with_route_hints(last_hops.clone()).unwrap();
4363 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
4364 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4365 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4366 &Default::default(), &random_seed_bytes).unwrap();
4367 assert_eq!(route.paths[0].hops.len(), 2);
4369 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
4370 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4371 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
4372 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4373 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
4374 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4376 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4377 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4378 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4379 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4380 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4381 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4383 last_hops[0].0[0].fees.base_msat = 1000;
4385 // Revert to via 6 as the fee on 8 goes up
4386 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4387 .with_route_hints(last_hops).unwrap();
4388 let route_params = RouteParameters::from_payment_params_and_value(
4389 payment_params.clone(), 100);
4390 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4391 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4392 assert_eq!(route.paths[0].hops.len(), 4);
4394 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4395 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4396 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4397 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4398 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4399 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4401 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4402 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4403 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4404 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4405 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4406 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4408 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4409 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4410 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4411 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4412 // If we have a peer in the node map, we'll use their features here since we don't have
4413 // a way of figuring out their features from the invoice:
4414 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4415 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4417 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4418 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4419 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4420 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4421 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4422 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4424 // ...but still use 8 for larger payments as 6 has a variable feerate
4425 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4426 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4427 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4428 assert_eq!(route.paths[0].hops.len(), 5);
4430 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4431 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4432 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4433 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4434 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4435 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4437 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4438 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4439 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4440 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4441 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4442 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4444 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4445 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4446 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4447 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4448 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4449 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4451 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4452 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4453 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4454 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4455 // If we have a peer in the node map, we'll use their features here since we don't have
4456 // a way of figuring out their features from the invoice:
4457 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4458 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4460 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4461 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4462 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4463 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4464 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4465 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4468 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> {
4469 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4470 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4471 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4473 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4474 let last_hops = RouteHint(vec![RouteHintHop {
4475 src_node_id: middle_node_id,
4476 short_channel_id: 8,
4479 proportional_millionths: last_hop_fee_prop,
4481 cltv_expiry_delta: (8 << 4) | 1,
4482 htlc_minimum_msat: None,
4483 htlc_maximum_msat: last_hop_htlc_max,
4485 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4486 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4487 let scorer = ln_test_utils::TestScorer::new();
4488 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4489 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4490 let logger = ln_test_utils::TestLogger::new();
4491 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4492 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4493 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4494 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4495 &random_seed_bytes);
4500 fn unannounced_path_test() {
4501 // We should be able to send a payment to a destination without any help of a routing graph
4502 // if we have a channel with a common counterparty that appears in the first and last hop
4504 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4506 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4507 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&<Vec<u8>>::from_hex(&format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4508 assert_eq!(route.paths[0].hops.len(), 2);
4510 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4511 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4512 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4513 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4514 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4515 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4517 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4518 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4519 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4520 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4521 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4522 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4526 fn overflow_unannounced_path_test_liquidity_underflow() {
4527 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4528 // the last-hop had a fee which overflowed a u64, we'd panic.
4529 // This was due to us adding the first-hop from us unconditionally, causing us to think
4530 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4531 // In this test, we previously hit a subtraction underflow due to having less available
4532 // liquidity at the last hop than 0.
4533 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());
4537 fn overflow_unannounced_path_test_feerate_overflow() {
4538 // This tests for the same case as above, except instead of hitting a subtraction
4539 // underflow, we hit a case where the fee charged at a hop overflowed.
4540 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());
4544 fn available_amount_while_routing_test() {
4545 // Tests whether we choose the correct available channel amount while routing.
4547 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4548 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4549 let scorer = ln_test_utils::TestScorer::new();
4550 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4551 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4552 let config = UserConfig::default();
4553 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4554 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4557 // We will use a simple single-path route from
4558 // our node to node2 via node0: channels {1, 3}.
4560 // First disable all other paths.
4561 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4562 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4563 short_channel_id: 2,
4566 cltv_expiry_delta: 0,
4567 htlc_minimum_msat: 0,
4568 htlc_maximum_msat: 100_000,
4570 fee_proportional_millionths: 0,
4571 excess_data: Vec::new()
4573 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4574 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4575 short_channel_id: 12,
4578 cltv_expiry_delta: 0,
4579 htlc_minimum_msat: 0,
4580 htlc_maximum_msat: 100_000,
4582 fee_proportional_millionths: 0,
4583 excess_data: Vec::new()
4586 // Make the first channel (#1) very permissive,
4587 // and we will be testing all limits on the second channel.
4588 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4589 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4590 short_channel_id: 1,
4593 cltv_expiry_delta: 0,
4594 htlc_minimum_msat: 0,
4595 htlc_maximum_msat: 1_000_000_000,
4597 fee_proportional_millionths: 0,
4598 excess_data: Vec::new()
4601 // First, let's see if routing works if we have absolutely no idea about the available amount.
4602 // In this case, it should be set to 250_000 sats.
4603 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4604 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4605 short_channel_id: 3,
4608 cltv_expiry_delta: 0,
4609 htlc_minimum_msat: 0,
4610 htlc_maximum_msat: 250_000_000,
4612 fee_proportional_millionths: 0,
4613 excess_data: Vec::new()
4617 // Attempt to route more than available results in a failure.
4618 let route_params = RouteParameters::from_payment_params_and_value(
4619 payment_params.clone(), 250_000_001);
4620 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4621 &our_id, &route_params, &network_graph.read_only(), None,
4622 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4623 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4624 } else { panic!(); }
4628 // Now, attempt to route an exact amount we have should be fine.
4629 let route_params = RouteParameters::from_payment_params_and_value(
4630 payment_params.clone(), 250_000_000);
4631 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4632 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4633 assert_eq!(route.paths.len(), 1);
4634 let path = route.paths.last().unwrap();
4635 assert_eq!(path.hops.len(), 2);
4636 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4637 assert_eq!(path.final_value_msat(), 250_000_000);
4640 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4641 // Disable channel #1 and use another first hop.
4642 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4643 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4644 short_channel_id: 1,
4647 cltv_expiry_delta: 0,
4648 htlc_minimum_msat: 0,
4649 htlc_maximum_msat: 1_000_000_000,
4651 fee_proportional_millionths: 0,
4652 excess_data: Vec::new()
4655 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4656 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4659 // Attempt to route more than available results in a failure.
4660 let route_params = RouteParameters::from_payment_params_and_value(
4661 payment_params.clone(), 200_000_001);
4662 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4663 &our_id, &route_params, &network_graph.read_only(),
4664 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4665 &Default::default(), &random_seed_bytes) {
4666 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4667 } else { panic!(); }
4671 // Now, attempt to route an exact amount we have should be fine.
4672 let route_params = RouteParameters::from_payment_params_and_value(
4673 payment_params.clone(), 200_000_000);
4674 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4675 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4676 &Default::default(), &random_seed_bytes).unwrap();
4677 assert_eq!(route.paths.len(), 1);
4678 let path = route.paths.last().unwrap();
4679 assert_eq!(path.hops.len(), 2);
4680 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4681 assert_eq!(path.final_value_msat(), 200_000_000);
4684 // Enable channel #1 back.
4685 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4686 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4687 short_channel_id: 1,
4690 cltv_expiry_delta: 0,
4691 htlc_minimum_msat: 0,
4692 htlc_maximum_msat: 1_000_000_000,
4694 fee_proportional_millionths: 0,
4695 excess_data: Vec::new()
4699 // Now let's see if routing works if we know only htlc_maximum_msat.
4700 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4701 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4702 short_channel_id: 3,
4705 cltv_expiry_delta: 0,
4706 htlc_minimum_msat: 0,
4707 htlc_maximum_msat: 15_000,
4709 fee_proportional_millionths: 0,
4710 excess_data: Vec::new()
4714 // Attempt to route more than available results in a failure.
4715 let route_params = RouteParameters::from_payment_params_and_value(
4716 payment_params.clone(), 15_001);
4717 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4718 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4719 &scorer, &Default::default(), &random_seed_bytes) {
4720 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4721 } else { panic!(); }
4725 // Now, attempt to route an exact amount we have should be fine.
4726 let route_params = RouteParameters::from_payment_params_and_value(
4727 payment_params.clone(), 15_000);
4728 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4729 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4730 assert_eq!(route.paths.len(), 1);
4731 let path = route.paths.last().unwrap();
4732 assert_eq!(path.hops.len(), 2);
4733 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4734 assert_eq!(path.final_value_msat(), 15_000);
4737 // Now let's see if routing works if we know only capacity from the UTXO.
4739 // We can't change UTXO capacity on the fly, so we'll disable
4740 // the existing channel and add another one with the capacity we need.
4741 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4742 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4743 short_channel_id: 3,
4746 cltv_expiry_delta: 0,
4747 htlc_minimum_msat: 0,
4748 htlc_maximum_msat: MAX_VALUE_MSAT,
4750 fee_proportional_millionths: 0,
4751 excess_data: Vec::new()
4754 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4755 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4756 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4757 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4758 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4760 *chain_monitor.utxo_ret.lock().unwrap() =
4761 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4762 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4764 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4765 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4766 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4767 short_channel_id: 333,
4770 cltv_expiry_delta: (3 << 4) | 1,
4771 htlc_minimum_msat: 0,
4772 htlc_maximum_msat: 15_000,
4774 fee_proportional_millionths: 0,
4775 excess_data: Vec::new()
4777 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4778 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4779 short_channel_id: 333,
4782 cltv_expiry_delta: (3 << 4) | 2,
4783 htlc_minimum_msat: 0,
4784 htlc_maximum_msat: 15_000,
4786 fee_proportional_millionths: 0,
4787 excess_data: Vec::new()
4791 // Attempt to route more than available results in a failure.
4792 let route_params = RouteParameters::from_payment_params_and_value(
4793 payment_params.clone(), 15_001);
4794 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4795 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4796 &scorer, &Default::default(), &random_seed_bytes) {
4797 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4798 } else { panic!(); }
4802 // Now, attempt to route an exact amount we have should be fine.
4803 let route_params = RouteParameters::from_payment_params_and_value(
4804 payment_params.clone(), 15_000);
4805 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4806 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4807 assert_eq!(route.paths.len(), 1);
4808 let path = route.paths.last().unwrap();
4809 assert_eq!(path.hops.len(), 2);
4810 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4811 assert_eq!(path.final_value_msat(), 15_000);
4814 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4815 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4816 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4817 short_channel_id: 333,
4820 cltv_expiry_delta: 0,
4821 htlc_minimum_msat: 0,
4822 htlc_maximum_msat: 10_000,
4824 fee_proportional_millionths: 0,
4825 excess_data: Vec::new()
4829 // Attempt to route more than available results in a failure.
4830 let route_params = RouteParameters::from_payment_params_and_value(
4831 payment_params.clone(), 10_001);
4832 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4833 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4834 &scorer, &Default::default(), &random_seed_bytes) {
4835 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4836 } else { panic!(); }
4840 // Now, attempt to route an exact amount we have should be fine.
4841 let route_params = RouteParameters::from_payment_params_and_value(
4842 payment_params.clone(), 10_000);
4843 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4844 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4845 assert_eq!(route.paths.len(), 1);
4846 let path = route.paths.last().unwrap();
4847 assert_eq!(path.hops.len(), 2);
4848 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4849 assert_eq!(path.final_value_msat(), 10_000);
4854 fn available_liquidity_last_hop_test() {
4855 // Check that available liquidity properly limits the path even when only
4856 // one of the latter hops is limited.
4857 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4858 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4859 let scorer = ln_test_utils::TestScorer::new();
4860 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4861 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4862 let config = UserConfig::default();
4863 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4864 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
4867 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4868 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4869 // Total capacity: 50 sats.
4871 // Disable other potential paths.
4872 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4873 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4874 short_channel_id: 2,
4877 cltv_expiry_delta: 0,
4878 htlc_minimum_msat: 0,
4879 htlc_maximum_msat: 100_000,
4881 fee_proportional_millionths: 0,
4882 excess_data: Vec::new()
4884 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4885 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4886 short_channel_id: 7,
4889 cltv_expiry_delta: 0,
4890 htlc_minimum_msat: 0,
4891 htlc_maximum_msat: 100_000,
4893 fee_proportional_millionths: 0,
4894 excess_data: Vec::new()
4899 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4900 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4901 short_channel_id: 12,
4904 cltv_expiry_delta: 0,
4905 htlc_minimum_msat: 0,
4906 htlc_maximum_msat: 100_000,
4908 fee_proportional_millionths: 0,
4909 excess_data: Vec::new()
4911 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4912 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4913 short_channel_id: 13,
4916 cltv_expiry_delta: 0,
4917 htlc_minimum_msat: 0,
4918 htlc_maximum_msat: 100_000,
4920 fee_proportional_millionths: 0,
4921 excess_data: Vec::new()
4924 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4925 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4926 short_channel_id: 6,
4929 cltv_expiry_delta: 0,
4930 htlc_minimum_msat: 0,
4931 htlc_maximum_msat: 50_000,
4933 fee_proportional_millionths: 0,
4934 excess_data: Vec::new()
4936 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4937 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
4938 short_channel_id: 11,
4941 cltv_expiry_delta: 0,
4942 htlc_minimum_msat: 0,
4943 htlc_maximum_msat: 100_000,
4945 fee_proportional_millionths: 0,
4946 excess_data: Vec::new()
4949 // Attempt to route more than available results in a failure.
4950 let route_params = RouteParameters::from_payment_params_and_value(
4951 payment_params.clone(), 60_000);
4952 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4953 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4954 &scorer, &Default::default(), &random_seed_bytes) {
4955 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4956 } else { panic!(); }
4960 // Now, attempt to route 49 sats (just a bit below the capacity).
4961 let route_params = RouteParameters::from_payment_params_and_value(
4962 payment_params.clone(), 49_000);
4963 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4964 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4965 assert_eq!(route.paths.len(), 1);
4966 let mut total_amount_paid_msat = 0;
4967 for path in &route.paths {
4968 assert_eq!(path.hops.len(), 4);
4969 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4970 total_amount_paid_msat += path.final_value_msat();
4972 assert_eq!(total_amount_paid_msat, 49_000);
4976 // Attempt to route an exact amount is also fine
4977 let route_params = RouteParameters::from_payment_params_and_value(
4978 payment_params, 50_000);
4979 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4980 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4981 assert_eq!(route.paths.len(), 1);
4982 let mut total_amount_paid_msat = 0;
4983 for path in &route.paths {
4984 assert_eq!(path.hops.len(), 4);
4985 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4986 total_amount_paid_msat += path.final_value_msat();
4988 assert_eq!(total_amount_paid_msat, 50_000);
4993 fn ignore_fee_first_hop_test() {
4994 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4995 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4996 let scorer = ln_test_utils::TestScorer::new();
4997 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4998 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4999 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5001 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5002 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5003 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5004 short_channel_id: 1,
5007 cltv_expiry_delta: 0,
5008 htlc_minimum_msat: 0,
5009 htlc_maximum_msat: 100_000,
5010 fee_base_msat: 1_000_000,
5011 fee_proportional_millionths: 0,
5012 excess_data: Vec::new()
5014 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5015 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5016 short_channel_id: 3,
5019 cltv_expiry_delta: 0,
5020 htlc_minimum_msat: 0,
5021 htlc_maximum_msat: 50_000,
5023 fee_proportional_millionths: 0,
5024 excess_data: Vec::new()
5028 let route_params = RouteParameters::from_payment_params_and_value(
5029 payment_params, 50_000);
5030 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5031 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5032 assert_eq!(route.paths.len(), 1);
5033 let mut total_amount_paid_msat = 0;
5034 for path in &route.paths {
5035 assert_eq!(path.hops.len(), 2);
5036 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5037 total_amount_paid_msat += path.final_value_msat();
5039 assert_eq!(total_amount_paid_msat, 50_000);
5044 fn simple_mpp_route_test() {
5045 let (secp_ctx, _, _, _, _) = build_graph();
5046 let (_, _, _, nodes) = get_nodes(&secp_ctx);
5047 let config = UserConfig::default();
5048 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5049 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5051 do_simple_mpp_route_test(clear_payment_params);
5053 // MPP to a 1-hop blinded path for nodes[2]
5054 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
5055 let blinded_path = BlindedPath {
5056 introduction_node_id: nodes[2],
5057 blinding_point: ln_test_utils::pubkey(42),
5058 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
5060 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
5062 fee_proportional_millionths: 0,
5063 htlc_minimum_msat: 0,
5064 htlc_maximum_msat: 0,
5065 cltv_expiry_delta: 0,
5066 features: BlindedHopFeatures::empty(),
5068 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
5069 .with_bolt12_features(bolt12_features.clone()).unwrap();
5070 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
5072 // MPP to 3 2-hop blinded paths
5073 let mut blinded_path_node_0 = blinded_path.clone();
5074 blinded_path_node_0.introduction_node_id = nodes[0];
5075 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
5076 let mut node_0_payinfo = blinded_payinfo.clone();
5077 node_0_payinfo.htlc_maximum_msat = 50_000;
5079 let mut blinded_path_node_7 = blinded_path_node_0.clone();
5080 blinded_path_node_7.introduction_node_id = nodes[7];
5081 let mut node_7_payinfo = blinded_payinfo.clone();
5082 node_7_payinfo.htlc_maximum_msat = 60_000;
5084 let mut blinded_path_node_1 = blinded_path_node_0.clone();
5085 blinded_path_node_1.introduction_node_id = nodes[1];
5086 let mut node_1_payinfo = blinded_payinfo.clone();
5087 node_1_payinfo.htlc_maximum_msat = 180_000;
5089 let two_hop_blinded_payment_params = PaymentParameters::blinded(
5091 (node_0_payinfo, blinded_path_node_0),
5092 (node_7_payinfo, blinded_path_node_7),
5093 (node_1_payinfo, blinded_path_node_1)
5095 .with_bolt12_features(bolt12_features).unwrap();
5096 do_simple_mpp_route_test(two_hop_blinded_payment_params);
5100 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
5101 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5102 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5103 let scorer = ln_test_utils::TestScorer::new();
5104 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5105 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5107 // We need a route consisting of 3 paths:
5108 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5109 // To achieve this, the amount being transferred should be around
5110 // the total capacity of these 3 paths.
5112 // First, we set limits on these (previously unlimited) channels.
5113 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
5115 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
5116 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5117 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5118 short_channel_id: 1,
5121 cltv_expiry_delta: 0,
5122 htlc_minimum_msat: 0,
5123 htlc_maximum_msat: 100_000,
5125 fee_proportional_millionths: 0,
5126 excess_data: Vec::new()
5128 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5129 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5130 short_channel_id: 3,
5133 cltv_expiry_delta: 0,
5134 htlc_minimum_msat: 0,
5135 htlc_maximum_msat: 50_000,
5137 fee_proportional_millionths: 0,
5138 excess_data: Vec::new()
5141 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
5142 // (total limit 60).
5143 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5144 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5145 short_channel_id: 12,
5148 cltv_expiry_delta: 0,
5149 htlc_minimum_msat: 0,
5150 htlc_maximum_msat: 60_000,
5152 fee_proportional_millionths: 0,
5153 excess_data: Vec::new()
5155 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5156 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5157 short_channel_id: 13,
5160 cltv_expiry_delta: 0,
5161 htlc_minimum_msat: 0,
5162 htlc_maximum_msat: 60_000,
5164 fee_proportional_millionths: 0,
5165 excess_data: Vec::new()
5168 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
5169 // (total capacity 180 sats).
5170 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5171 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5172 short_channel_id: 2,
5175 cltv_expiry_delta: 0,
5176 htlc_minimum_msat: 0,
5177 htlc_maximum_msat: 200_000,
5179 fee_proportional_millionths: 0,
5180 excess_data: Vec::new()
5182 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5183 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5184 short_channel_id: 4,
5187 cltv_expiry_delta: 0,
5188 htlc_minimum_msat: 0,
5189 htlc_maximum_msat: 180_000,
5191 fee_proportional_millionths: 0,
5192 excess_data: Vec::new()
5196 // Attempt to route more than available results in a failure.
5197 let route_params = RouteParameters::from_payment_params_and_value(
5198 payment_params.clone(), 300_000);
5199 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5200 &our_id, &route_params, &network_graph.read_only(), None,
5201 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5202 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5203 } else { panic!(); }
5207 // Attempt to route while setting max_path_count to 0 results in a failure.
5208 let zero_payment_params = payment_params.clone().with_max_path_count(0);
5209 let route_params = RouteParameters::from_payment_params_and_value(
5210 zero_payment_params, 100);
5211 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5212 &our_id, &route_params, &network_graph.read_only(), None,
5213 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5214 assert_eq!(err, "Can't find a route with no paths allowed.");
5215 } else { panic!(); }
5219 // Attempt to route while setting max_path_count to 3 results in a failure.
5220 // This is the case because the minimal_value_contribution_msat would require each path
5221 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
5222 let fail_payment_params = payment_params.clone().with_max_path_count(3);
5223 let route_params = RouteParameters::from_payment_params_and_value(
5224 fail_payment_params, 250_000);
5225 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5226 &our_id, &route_params, &network_graph.read_only(), None,
5227 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
5228 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5229 } else { panic!(); }
5233 // Now, attempt to route 250 sats (just a bit below the capacity).
5234 // Our algorithm should provide us with these 3 paths.
5235 let route_params = RouteParameters::from_payment_params_and_value(
5236 payment_params.clone(), 250_000);
5237 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5238 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5239 assert_eq!(route.paths.len(), 3);
5240 let mut total_amount_paid_msat = 0;
5241 for path in &route.paths {
5242 if let Some(bt) = &path.blinded_tail {
5243 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5245 assert_eq!(path.hops.len(), 2);
5246 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5248 total_amount_paid_msat += path.final_value_msat();
5250 assert_eq!(total_amount_paid_msat, 250_000);
5254 // Attempt to route an exact amount is also fine
5255 let route_params = RouteParameters::from_payment_params_and_value(
5256 payment_params.clone(), 290_000);
5257 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5258 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5259 assert_eq!(route.paths.len(), 3);
5260 let mut total_amount_paid_msat = 0;
5261 for path in &route.paths {
5262 if payment_params.payee.blinded_route_hints().len() != 0 {
5263 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
5264 if let Some(bt) = &path.blinded_tail {
5265 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
5266 if bt.hops.len() > 1 {
5267 assert_eq!(path.hops.last().unwrap().pubkey,
5268 payment_params.payee.blinded_route_hints().iter()
5269 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
5270 .map(|(_, p)| p.introduction_node_id).unwrap());
5272 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5275 assert_eq!(path.hops.len(), 2);
5276 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5278 total_amount_paid_msat += path.final_value_msat();
5280 assert_eq!(total_amount_paid_msat, 290_000);
5285 fn long_mpp_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 // We need a route consisting of 3 paths:
5297 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5298 // Note that these paths overlap (channels 5, 12, 13).
5299 // We will route 300 sats.
5300 // Each path will have 100 sats capacity, those channels which
5301 // are used twice will have 200 sats capacity.
5303 // Disable other potential paths.
5304 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5305 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5306 short_channel_id: 2,
5309 cltv_expiry_delta: 0,
5310 htlc_minimum_msat: 0,
5311 htlc_maximum_msat: 100_000,
5313 fee_proportional_millionths: 0,
5314 excess_data: Vec::new()
5316 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5317 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5318 short_channel_id: 7,
5321 cltv_expiry_delta: 0,
5322 htlc_minimum_msat: 0,
5323 htlc_maximum_msat: 100_000,
5325 fee_proportional_millionths: 0,
5326 excess_data: Vec::new()
5329 // Path via {node0, node2} is channels {1, 3, 5}.
5330 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5331 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5332 short_channel_id: 1,
5335 cltv_expiry_delta: 0,
5336 htlc_minimum_msat: 0,
5337 htlc_maximum_msat: 100_000,
5339 fee_proportional_millionths: 0,
5340 excess_data: Vec::new()
5342 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5343 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5344 short_channel_id: 3,
5347 cltv_expiry_delta: 0,
5348 htlc_minimum_msat: 0,
5349 htlc_maximum_msat: 100_000,
5351 fee_proportional_millionths: 0,
5352 excess_data: Vec::new()
5355 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5356 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5357 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5358 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5359 short_channel_id: 5,
5362 cltv_expiry_delta: 0,
5363 htlc_minimum_msat: 0,
5364 htlc_maximum_msat: 200_000,
5366 fee_proportional_millionths: 0,
5367 excess_data: Vec::new()
5370 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5371 // Add 100 sats to the capacities of {12, 13}, because these channels
5372 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5373 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5374 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5375 short_channel_id: 12,
5378 cltv_expiry_delta: 0,
5379 htlc_minimum_msat: 0,
5380 htlc_maximum_msat: 200_000,
5382 fee_proportional_millionths: 0,
5383 excess_data: Vec::new()
5385 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5386 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5387 short_channel_id: 13,
5390 cltv_expiry_delta: 0,
5391 htlc_minimum_msat: 0,
5392 htlc_maximum_msat: 200_000,
5394 fee_proportional_millionths: 0,
5395 excess_data: Vec::new()
5398 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5399 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5400 short_channel_id: 6,
5403 cltv_expiry_delta: 0,
5404 htlc_minimum_msat: 0,
5405 htlc_maximum_msat: 100_000,
5407 fee_proportional_millionths: 0,
5408 excess_data: Vec::new()
5410 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5411 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5412 short_channel_id: 11,
5415 cltv_expiry_delta: 0,
5416 htlc_minimum_msat: 0,
5417 htlc_maximum_msat: 100_000,
5419 fee_proportional_millionths: 0,
5420 excess_data: Vec::new()
5423 // Path via {node7, node2} is channels {12, 13, 5}.
5424 // We already limited them to 200 sats (they are used twice for 100 sats).
5425 // Nothing to do here.
5428 // Attempt to route more than available results in a failure.
5429 let route_params = RouteParameters::from_payment_params_and_value(
5430 payment_params.clone(), 350_000);
5431 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5432 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5433 &scorer, &Default::default(), &random_seed_bytes) {
5434 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5435 } else { panic!(); }
5439 // Now, attempt to route 300 sats (exact amount we can route).
5440 // Our algorithm should provide us with these 3 paths, 100 sats each.
5441 let route_params = RouteParameters::from_payment_params_and_value(
5442 payment_params, 300_000);
5443 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5444 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5445 assert_eq!(route.paths.len(), 3);
5447 let mut total_amount_paid_msat = 0;
5448 for path in &route.paths {
5449 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5450 total_amount_paid_msat += path.final_value_msat();
5452 assert_eq!(total_amount_paid_msat, 300_000);
5458 fn mpp_cheaper_route_test() {
5459 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5460 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5461 let scorer = ln_test_utils::TestScorer::new();
5462 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5463 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5464 let config = UserConfig::default();
5465 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5466 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5469 // This test checks that if we have two cheaper paths and one more expensive path,
5470 // so that liquidity-wise any 2 of 3 combination is sufficient,
5471 // two cheaper paths will be taken.
5472 // These paths have equal available liquidity.
5474 // We need a combination of 3 paths:
5475 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5476 // Note that these paths overlap (channels 5, 12, 13).
5477 // Each path will have 100 sats capacity, those channels which
5478 // are used twice will have 200 sats capacity.
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()
5493 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5494 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5495 short_channel_id: 7,
5498 cltv_expiry_delta: 0,
5499 htlc_minimum_msat: 0,
5500 htlc_maximum_msat: 100_000,
5502 fee_proportional_millionths: 0,
5503 excess_data: Vec::new()
5506 // Path via {node0, node2} is channels {1, 3, 5}.
5507 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5508 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5509 short_channel_id: 1,
5512 cltv_expiry_delta: 0,
5513 htlc_minimum_msat: 0,
5514 htlc_maximum_msat: 100_000,
5516 fee_proportional_millionths: 0,
5517 excess_data: Vec::new()
5519 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5520 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5521 short_channel_id: 3,
5524 cltv_expiry_delta: 0,
5525 htlc_minimum_msat: 0,
5526 htlc_maximum_msat: 100_000,
5528 fee_proportional_millionths: 0,
5529 excess_data: Vec::new()
5532 // Capacity of 200 sats because this channel will be used by 3rd path as well.
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: 200_000,
5543 fee_proportional_millionths: 0,
5544 excess_data: Vec::new()
5547 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5548 // Add 100 sats to the capacities of {12, 13}, because these channels
5549 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5550 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5551 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5552 short_channel_id: 12,
5555 cltv_expiry_delta: 0,
5556 htlc_minimum_msat: 0,
5557 htlc_maximum_msat: 200_000,
5559 fee_proportional_millionths: 0,
5560 excess_data: Vec::new()
5562 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5563 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5564 short_channel_id: 13,
5567 cltv_expiry_delta: 0,
5568 htlc_minimum_msat: 0,
5569 htlc_maximum_msat: 200_000,
5571 fee_proportional_millionths: 0,
5572 excess_data: Vec::new()
5575 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5576 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5577 short_channel_id: 6,
5580 cltv_expiry_delta: 0,
5581 htlc_minimum_msat: 0,
5582 htlc_maximum_msat: 100_000,
5583 fee_base_msat: 1_000,
5584 fee_proportional_millionths: 0,
5585 excess_data: Vec::new()
5587 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5588 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5589 short_channel_id: 11,
5592 cltv_expiry_delta: 0,
5593 htlc_minimum_msat: 0,
5594 htlc_maximum_msat: 100_000,
5596 fee_proportional_millionths: 0,
5597 excess_data: Vec::new()
5600 // Path via {node7, node2} is channels {12, 13, 5}.
5601 // We already limited them to 200 sats (they are used twice for 100 sats).
5602 // Nothing to do here.
5605 // Now, attempt to route 180 sats.
5606 // Our algorithm should provide us with these 2 paths.
5607 let route_params = RouteParameters::from_payment_params_and_value(
5608 payment_params, 180_000);
5609 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5610 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5611 assert_eq!(route.paths.len(), 2);
5613 let mut total_value_transferred_msat = 0;
5614 let mut total_paid_msat = 0;
5615 for path in &route.paths {
5616 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5617 total_value_transferred_msat += path.final_value_msat();
5618 for hop in &path.hops {
5619 total_paid_msat += hop.fee_msat;
5622 // If we paid fee, this would be higher.
5623 assert_eq!(total_value_transferred_msat, 180_000);
5624 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5625 assert_eq!(total_fees_paid, 0);
5630 fn fees_on_mpp_route_test() {
5631 // This test makes sure that MPP algorithm properly takes into account
5632 // fees charged on the channels, by making the fees impactful:
5633 // if the fee is not properly accounted for, the behavior is different.
5634 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5635 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5636 let scorer = ln_test_utils::TestScorer::new();
5637 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5638 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5639 let config = UserConfig::default();
5640 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
5641 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5644 // We need a route consisting of 2 paths:
5645 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5646 // We will route 200 sats, Each path will have 100 sats capacity.
5648 // This test is not particularly stable: e.g.,
5649 // there's a way to route via {node0, node2, node4}.
5650 // It works while pathfinding is deterministic, but can be broken otherwise.
5651 // It's fine to ignore this concern for now.
5653 // Disable other potential paths.
5654 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5655 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5656 short_channel_id: 2,
5659 cltv_expiry_delta: 0,
5660 htlc_minimum_msat: 0,
5661 htlc_maximum_msat: 100_000,
5663 fee_proportional_millionths: 0,
5664 excess_data: Vec::new()
5667 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5668 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5669 short_channel_id: 7,
5672 cltv_expiry_delta: 0,
5673 htlc_minimum_msat: 0,
5674 htlc_maximum_msat: 100_000,
5676 fee_proportional_millionths: 0,
5677 excess_data: Vec::new()
5680 // Path via {node0, node2} is channels {1, 3, 5}.
5681 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5682 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5683 short_channel_id: 1,
5686 cltv_expiry_delta: 0,
5687 htlc_minimum_msat: 0,
5688 htlc_maximum_msat: 100_000,
5690 fee_proportional_millionths: 0,
5691 excess_data: Vec::new()
5693 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5694 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5695 short_channel_id: 3,
5698 cltv_expiry_delta: 0,
5699 htlc_minimum_msat: 0,
5700 htlc_maximum_msat: 100_000,
5702 fee_proportional_millionths: 0,
5703 excess_data: Vec::new()
5706 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5707 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5708 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5709 short_channel_id: 5,
5712 cltv_expiry_delta: 0,
5713 htlc_minimum_msat: 0,
5714 htlc_maximum_msat: 100_000,
5716 fee_proportional_millionths: 0,
5717 excess_data: Vec::new()
5720 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5721 // All channels should be 100 sats capacity. But for the fee experiment,
5722 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5723 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5724 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5725 // so no matter how large are other channels,
5726 // the whole path will be limited by 100 sats with just these 2 conditions:
5727 // - channel 12 capacity is 250 sats
5728 // - fee for channel 6 is 150 sats
5729 // Let's test this by enforcing these 2 conditions and removing other limits.
5730 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5731 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5732 short_channel_id: 12,
5735 cltv_expiry_delta: 0,
5736 htlc_minimum_msat: 0,
5737 htlc_maximum_msat: 250_000,
5739 fee_proportional_millionths: 0,
5740 excess_data: Vec::new()
5742 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5743 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5744 short_channel_id: 13,
5747 cltv_expiry_delta: 0,
5748 htlc_minimum_msat: 0,
5749 htlc_maximum_msat: MAX_VALUE_MSAT,
5751 fee_proportional_millionths: 0,
5752 excess_data: Vec::new()
5755 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5756 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5757 short_channel_id: 6,
5760 cltv_expiry_delta: 0,
5761 htlc_minimum_msat: 0,
5762 htlc_maximum_msat: MAX_VALUE_MSAT,
5763 fee_base_msat: 150_000,
5764 fee_proportional_millionths: 0,
5765 excess_data: Vec::new()
5767 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5768 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5769 short_channel_id: 11,
5772 cltv_expiry_delta: 0,
5773 htlc_minimum_msat: 0,
5774 htlc_maximum_msat: MAX_VALUE_MSAT,
5776 fee_proportional_millionths: 0,
5777 excess_data: Vec::new()
5781 // Attempt to route more than available results in a failure.
5782 let route_params = RouteParameters::from_payment_params_and_value(
5783 payment_params.clone(), 210_000);
5784 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5785 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5786 &scorer, &Default::default(), &random_seed_bytes) {
5787 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5788 } else { panic!(); }
5792 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5793 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5794 max_total_routing_fee_msat: Some(149_999) };
5795 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5796 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5797 &scorer, &Default::default(), &random_seed_bytes) {
5798 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5799 } else { panic!(); }
5803 // Now, attempt to route 200 sats (exact amount we can route).
5804 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5805 max_total_routing_fee_msat: Some(150_000) };
5806 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5807 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5808 assert_eq!(route.paths.len(), 2);
5810 let mut total_amount_paid_msat = 0;
5811 for path in &route.paths {
5812 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5813 total_amount_paid_msat += path.final_value_msat();
5815 assert_eq!(total_amount_paid_msat, 200_000);
5816 assert_eq!(route.get_total_fees(), 150_000);
5821 fn mpp_with_last_hops() {
5822 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5823 // via a single last-hop route hint, we'd fail to route if we first collected routes
5824 // totaling close but not quite enough to fund the full payment.
5826 // This was because we considered last-hop hints to have exactly the sought payment amount
5827 // instead of the amount we were trying to collect, needlessly limiting our path searching
5828 // at the very first hop.
5830 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5831 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5832 // to only have the remaining to-collect amount in available liquidity.
5834 // This bug appeared in production in some specific channel configurations.
5835 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5836 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5837 let scorer = ln_test_utils::TestScorer::new();
5838 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5839 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5840 let config = UserConfig::default();
5841 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42)
5842 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
5843 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5844 src_node_id: nodes[2],
5845 short_channel_id: 42,
5846 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5847 cltv_expiry_delta: 42,
5848 htlc_minimum_msat: None,
5849 htlc_maximum_msat: None,
5850 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5852 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5853 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5854 // would first use the no-fee route and then fail to find a path along the second route as
5855 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5856 // under 5% of our payment amount.
5857 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5858 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5859 short_channel_id: 1,
5862 cltv_expiry_delta: (5 << 4) | 5,
5863 htlc_minimum_msat: 0,
5864 htlc_maximum_msat: 99_000,
5865 fee_base_msat: u32::max_value(),
5866 fee_proportional_millionths: u32::max_value(),
5867 excess_data: Vec::new()
5869 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5870 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5871 short_channel_id: 2,
5874 cltv_expiry_delta: (5 << 4) | 3,
5875 htlc_minimum_msat: 0,
5876 htlc_maximum_msat: 99_000,
5877 fee_base_msat: u32::max_value(),
5878 fee_proportional_millionths: u32::max_value(),
5879 excess_data: Vec::new()
5881 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5882 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5883 short_channel_id: 4,
5886 cltv_expiry_delta: (4 << 4) | 1,
5887 htlc_minimum_msat: 0,
5888 htlc_maximum_msat: MAX_VALUE_MSAT,
5890 fee_proportional_millionths: 0,
5891 excess_data: Vec::new()
5893 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5894 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5895 short_channel_id: 13,
5897 flags: 0|2, // Channel disabled
5898 cltv_expiry_delta: (13 << 4) | 1,
5899 htlc_minimum_msat: 0,
5900 htlc_maximum_msat: MAX_VALUE_MSAT,
5902 fee_proportional_millionths: 2000000,
5903 excess_data: Vec::new()
5906 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5908 let route_params = RouteParameters::from_payment_params_and_value(
5909 payment_params, 100_000);
5910 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5911 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5912 assert_eq!(route.paths.len(), 2);
5913 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5914 // Paths are manually ordered ordered by SCID, so:
5915 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5916 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5917 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5918 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5919 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5920 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5921 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5922 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5923 assert_eq!(route.get_total_fees(), 1);
5924 assert_eq!(route.get_total_amount(), 100_000);
5928 fn drop_lowest_channel_mpp_route_test() {
5929 // This test checks that low-capacity channel is dropped when after
5930 // path finding we realize that we found more capacity than we need.
5931 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5932 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5933 let scorer = ln_test_utils::TestScorer::new();
5934 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5935 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5936 let config = UserConfig::default();
5937 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
5938 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
5940 .with_max_channel_saturation_power_of_half(0);
5942 // We need a route consisting of 3 paths:
5943 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5945 // The first and the second paths should be sufficient, but the third should be
5946 // cheaper, so that we select it but drop later.
5948 // First, we set limits on these (previously unlimited) channels.
5949 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5951 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5952 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5953 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5954 short_channel_id: 1,
5957 cltv_expiry_delta: 0,
5958 htlc_minimum_msat: 0,
5959 htlc_maximum_msat: 100_000,
5961 fee_proportional_millionths: 0,
5962 excess_data: Vec::new()
5964 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5965 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5966 short_channel_id: 3,
5969 cltv_expiry_delta: 0,
5970 htlc_minimum_msat: 0,
5971 htlc_maximum_msat: 50_000,
5973 fee_proportional_millionths: 0,
5974 excess_data: Vec::new()
5977 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5978 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5979 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5980 short_channel_id: 12,
5983 cltv_expiry_delta: 0,
5984 htlc_minimum_msat: 0,
5985 htlc_maximum_msat: 60_000,
5987 fee_proportional_millionths: 0,
5988 excess_data: Vec::new()
5990 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5991 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
5992 short_channel_id: 13,
5995 cltv_expiry_delta: 0,
5996 htlc_minimum_msat: 0,
5997 htlc_maximum_msat: 60_000,
5999 fee_proportional_millionths: 0,
6000 excess_data: Vec::new()
6003 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
6004 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6005 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6006 short_channel_id: 2,
6009 cltv_expiry_delta: 0,
6010 htlc_minimum_msat: 0,
6011 htlc_maximum_msat: 20_000,
6013 fee_proportional_millionths: 0,
6014 excess_data: Vec::new()
6016 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6017 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6018 short_channel_id: 4,
6021 cltv_expiry_delta: 0,
6022 htlc_minimum_msat: 0,
6023 htlc_maximum_msat: 20_000,
6025 fee_proportional_millionths: 0,
6026 excess_data: Vec::new()
6030 // Attempt to route more than available results in a failure.
6031 let route_params = RouteParameters::from_payment_params_and_value(
6032 payment_params.clone(), 150_000);
6033 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
6034 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
6035 &scorer, &Default::default(), &random_seed_bytes) {
6036 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6037 } else { panic!(); }
6041 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
6042 // Our algorithm should provide us with these 3 paths.
6043 let route_params = RouteParameters::from_payment_params_and_value(
6044 payment_params.clone(), 125_000);
6045 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6046 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6047 assert_eq!(route.paths.len(), 3);
6048 let mut total_amount_paid_msat = 0;
6049 for path in &route.paths {
6050 assert_eq!(path.hops.len(), 2);
6051 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6052 total_amount_paid_msat += path.final_value_msat();
6054 assert_eq!(total_amount_paid_msat, 125_000);
6058 // Attempt to route without the last small cheap channel
6059 let route_params = RouteParameters::from_payment_params_and_value(
6060 payment_params, 90_000);
6061 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6062 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6063 assert_eq!(route.paths.len(), 2);
6064 let mut total_amount_paid_msat = 0;
6065 for path in &route.paths {
6066 assert_eq!(path.hops.len(), 2);
6067 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6068 total_amount_paid_msat += path.final_value_msat();
6070 assert_eq!(total_amount_paid_msat, 90_000);
6075 fn min_criteria_consistency() {
6076 // Test that we don't use an inconsistent metric between updating and walking nodes during
6077 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
6078 // was updated with a different criterion from the heap sorting, resulting in loops in
6079 // calculated paths. We test for that specific case here.
6081 // We construct a network that looks like this:
6083 // node2 -1(3)2- node3
6087 // node1 -1(5)2- node4 -1(1)2- node6
6093 // We create a loop on the side of our real path - our destination is node 6, with a
6094 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
6095 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
6096 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
6097 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
6098 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
6099 // "previous hop" being set to node 3, creating a loop in the path.
6100 let secp_ctx = Secp256k1::new();
6101 let logger = Arc::new(ln_test_utils::TestLogger::new());
6102 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6103 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
6104 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6105 let scorer = ln_test_utils::TestScorer::new();
6106 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6107 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6108 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
6110 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
6111 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6112 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6113 short_channel_id: 6,
6116 cltv_expiry_delta: (6 << 4) | 0,
6117 htlc_minimum_msat: 0,
6118 htlc_maximum_msat: MAX_VALUE_MSAT,
6120 fee_proportional_millionths: 0,
6121 excess_data: Vec::new()
6123 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
6125 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
6126 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6127 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6128 short_channel_id: 5,
6131 cltv_expiry_delta: (5 << 4) | 0,
6132 htlc_minimum_msat: 0,
6133 htlc_maximum_msat: MAX_VALUE_MSAT,
6135 fee_proportional_millionths: 0,
6136 excess_data: Vec::new()
6138 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
6140 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
6141 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6142 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6143 short_channel_id: 4,
6146 cltv_expiry_delta: (4 << 4) | 0,
6147 htlc_minimum_msat: 0,
6148 htlc_maximum_msat: MAX_VALUE_MSAT,
6150 fee_proportional_millionths: 0,
6151 excess_data: Vec::new()
6153 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
6155 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
6156 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
6157 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6158 short_channel_id: 3,
6161 cltv_expiry_delta: (3 << 4) | 0,
6162 htlc_minimum_msat: 0,
6163 htlc_maximum_msat: MAX_VALUE_MSAT,
6165 fee_proportional_millionths: 0,
6166 excess_data: Vec::new()
6168 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
6170 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
6171 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
6172 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6173 short_channel_id: 2,
6176 cltv_expiry_delta: (2 << 4) | 0,
6177 htlc_minimum_msat: 0,
6178 htlc_maximum_msat: MAX_VALUE_MSAT,
6180 fee_proportional_millionths: 0,
6181 excess_data: Vec::new()
6184 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6185 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
6186 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6187 short_channel_id: 1,
6190 cltv_expiry_delta: (1 << 4) | 0,
6191 htlc_minimum_msat: 100,
6192 htlc_maximum_msat: MAX_VALUE_MSAT,
6194 fee_proportional_millionths: 0,
6195 excess_data: Vec::new()
6197 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
6200 // Now ensure the route flows simply over nodes 1 and 4 to 6.
6201 let route_params = RouteParameters::from_payment_params_and_value(
6202 payment_params, 10_000);
6203 let route = get_route(&our_id, &route_params, &network.read_only(), None,
6204 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6205 assert_eq!(route.paths.len(), 1);
6206 assert_eq!(route.paths[0].hops.len(), 3);
6208 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
6209 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6210 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
6211 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
6212 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
6213 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
6215 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
6216 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
6217 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
6218 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
6219 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
6220 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
6222 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
6223 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
6224 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
6225 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
6226 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
6227 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
6233 fn exact_fee_liquidity_limit() {
6234 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
6235 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
6236 // we calculated fees on a higher value, resulting in us ignoring such paths.
6237 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6238 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
6239 let scorer = ln_test_utils::TestScorer::new();
6240 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6241 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6242 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
6244 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
6246 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6247 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6248 short_channel_id: 2,
6251 cltv_expiry_delta: 0,
6252 htlc_minimum_msat: 0,
6253 htlc_maximum_msat: 85_000,
6255 fee_proportional_millionths: 0,
6256 excess_data: Vec::new()
6259 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6260 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6261 short_channel_id: 12,
6264 cltv_expiry_delta: (4 << 4) | 1,
6265 htlc_minimum_msat: 0,
6266 htlc_maximum_msat: 270_000,
6268 fee_proportional_millionths: 1000000,
6269 excess_data: Vec::new()
6273 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
6274 // 200% fee charged channel 13 in the 1-to-2 direction.
6275 let mut route_params = RouteParameters::from_payment_params_and_value(
6276 payment_params, 90_000);
6277 route_params.max_total_routing_fee_msat = Some(90_000*2);
6278 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6279 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6280 assert_eq!(route.paths.len(), 1);
6281 assert_eq!(route.paths[0].hops.len(), 2);
6283 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6284 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6285 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6286 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6287 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6288 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6290 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6291 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6292 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6293 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6294 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
6295 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6300 fn htlc_max_reduction_below_min() {
6301 // Test that if, while walking the graph, we reduce the value being sent to meet an
6302 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
6303 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
6304 // resulting in us thinking there is no possible path, even if other paths exist.
6305 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6306 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6307 let scorer = ln_test_utils::TestScorer::new();
6308 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6309 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6310 let config = UserConfig::default();
6311 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6312 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6315 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
6316 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
6317 // then try to send 90_000.
6318 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
6319 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6320 short_channel_id: 2,
6323 cltv_expiry_delta: 0,
6324 htlc_minimum_msat: 0,
6325 htlc_maximum_msat: 80_000,
6327 fee_proportional_millionths: 0,
6328 excess_data: Vec::new()
6330 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6331 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6332 short_channel_id: 4,
6335 cltv_expiry_delta: (4 << 4) | 1,
6336 htlc_minimum_msat: 90_000,
6337 htlc_maximum_msat: MAX_VALUE_MSAT,
6339 fee_proportional_millionths: 0,
6340 excess_data: Vec::new()
6344 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
6345 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
6346 // expensive) channels 12-13 path.
6347 let mut route_params = RouteParameters::from_payment_params_and_value(
6348 payment_params, 90_000);
6349 route_params.max_total_routing_fee_msat = Some(90_000*2);
6350 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6351 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6352 assert_eq!(route.paths.len(), 1);
6353 assert_eq!(route.paths[0].hops.len(), 2);
6355 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
6356 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
6357 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
6358 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
6359 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
6360 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
6362 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
6363 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
6364 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
6365 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
6366 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_bolt11_invoice_features(&config).le_flags());
6367 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
6372 fn multiple_direct_first_hops() {
6373 // Previously we'd only ever considered one first hop path per counterparty.
6374 // However, as we don't restrict users to one channel per peer, we really need to support
6375 // looking at all first hop paths.
6376 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
6377 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
6378 // route over multiple channels with the same first hop.
6379 let secp_ctx = Secp256k1::new();
6380 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6381 let logger = Arc::new(ln_test_utils::TestLogger::new());
6382 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
6383 let scorer = ln_test_utils::TestScorer::new();
6384 let config = UserConfig::default();
6385 let payment_params = PaymentParameters::from_node_id(nodes[0], 42)
6386 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6388 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6389 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6392 let route_params = RouteParameters::from_payment_params_and_value(
6393 payment_params.clone(), 100_000);
6394 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6395 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6396 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6397 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6398 assert_eq!(route.paths.len(), 1);
6399 assert_eq!(route.paths[0].hops.len(), 1);
6401 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6402 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6403 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6406 let route_params = RouteParameters::from_payment_params_and_value(
6407 payment_params.clone(), 100_000);
6408 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6409 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6410 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6411 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6412 assert_eq!(route.paths.len(), 2);
6413 assert_eq!(route.paths[0].hops.len(), 1);
6414 assert_eq!(route.paths[1].hops.len(), 1);
6416 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6417 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6419 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6420 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6422 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6423 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6427 // If we have a bunch of outbound channels to the same node, where most are not
6428 // sufficient to pay the full payment, but one is, we should default to just using the
6429 // one single channel that has sufficient balance, avoiding MPP.
6431 // If we have several options above the 3xpayment value threshold, we should pick the
6432 // smallest of them, avoiding further fragmenting our available outbound balance to
6434 let route_params = RouteParameters::from_payment_params_and_value(
6435 payment_params, 100_000);
6436 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6437 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6438 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6439 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6440 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6441 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6442 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6443 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6444 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6445 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6446 assert_eq!(route.paths.len(), 1);
6447 assert_eq!(route.paths[0].hops.len(), 1);
6449 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6450 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6451 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6456 fn prefers_shorter_route_with_higher_fees() {
6457 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6458 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6459 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6461 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6462 let scorer = ln_test_utils::TestScorer::new();
6463 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6464 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6465 let route_params = RouteParameters::from_payment_params_and_value(
6466 payment_params.clone(), 100);
6467 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6468 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6469 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6471 assert_eq!(route.get_total_fees(), 100);
6472 assert_eq!(route.get_total_amount(), 100);
6473 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6475 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6476 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6477 let scorer = FixedPenaltyScorer::with_penalty(100);
6478 let route_params = RouteParameters::from_payment_params_and_value(
6479 payment_params, 100);
6480 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6481 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6482 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6484 assert_eq!(route.get_total_fees(), 300);
6485 assert_eq!(route.get_total_amount(), 100);
6486 assert_eq!(path, vec![2, 4, 7, 10]);
6489 struct BadChannelScorer {
6490 short_channel_id: u64,
6494 impl Writeable for BadChannelScorer {
6495 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6497 impl ScoreLookUp for BadChannelScorer {
6498 type ScoreParams = ();
6499 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6500 if candidate.short_channel_id() == Some(self.short_channel_id) { u64::max_value() } else { 0 }
6504 struct BadNodeScorer {
6509 impl Writeable for BadNodeScorer {
6510 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6513 impl ScoreLookUp for BadNodeScorer {
6514 type ScoreParams = ();
6515 fn channel_penalty_msat(&self, candidate: &CandidateRouteHop, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6516 if candidate.target() == Some(self.node_id) { u64::max_value() } else { 0 }
6521 fn avoids_routing_through_bad_channels_and_nodes() {
6522 let (secp_ctx, network, _, _, logger) = build_graph();
6523 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6524 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6525 let network_graph = network.read_only();
6527 // A path to nodes[6] exists when no penalties are applied to any channel.
6528 let scorer = ln_test_utils::TestScorer::new();
6529 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6530 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6531 let route_params = RouteParameters::from_payment_params_and_value(
6532 payment_params, 100);
6533 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6534 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6535 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6537 assert_eq!(route.get_total_fees(), 100);
6538 assert_eq!(route.get_total_amount(), 100);
6539 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6541 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6542 let scorer = BadChannelScorer { short_channel_id: 6 };
6543 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6544 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6545 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6547 assert_eq!(route.get_total_fees(), 300);
6548 assert_eq!(route.get_total_amount(), 100);
6549 assert_eq!(path, vec![2, 4, 7, 10]);
6551 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6552 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6553 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6554 &scorer, &Default::default(), &random_seed_bytes) {
6555 Err(LightningError { err, .. } ) => {
6556 assert_eq!(err, "Failed to find a path to the given destination");
6558 Ok(_) => panic!("Expected error"),
6563 fn total_fees_single_path() {
6565 paths: vec![Path { hops: vec![
6567 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6568 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6569 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6572 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6573 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6574 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6577 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6578 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6579 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6581 ], blinded_tail: None }],
6585 assert_eq!(route.get_total_fees(), 250);
6586 assert_eq!(route.get_total_amount(), 225);
6590 fn total_fees_multi_path() {
6592 paths: vec![Path { hops: vec![
6594 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6595 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6596 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6599 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6600 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6601 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6603 ], blinded_tail: None }, Path { hops: vec![
6605 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6606 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6607 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6610 pubkey: PublicKey::from_slice(&<Vec<u8>>::from_hex("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6611 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6612 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6614 ], blinded_tail: None }],
6618 assert_eq!(route.get_total_fees(), 200);
6619 assert_eq!(route.get_total_amount(), 300);
6623 fn total_empty_route_no_panic() {
6624 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6625 // would both panic if the route was completely empty. We test to ensure they return 0
6626 // here, even though its somewhat nonsensical as a route.
6627 let route = Route { paths: Vec::new(), route_params: None };
6629 assert_eq!(route.get_total_fees(), 0);
6630 assert_eq!(route.get_total_amount(), 0);
6634 fn limits_total_cltv_delta() {
6635 let (secp_ctx, network, _, _, logger) = build_graph();
6636 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6637 let network_graph = network.read_only();
6639 let scorer = ln_test_utils::TestScorer::new();
6641 // Make sure that generally there is at least one route available
6642 let feasible_max_total_cltv_delta = 1008;
6643 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6644 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6645 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6646 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6647 let route_params = RouteParameters::from_payment_params_and_value(
6648 feasible_payment_params, 100);
6649 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6650 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6651 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6652 assert_ne!(path.len(), 0);
6654 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6655 let fail_max_total_cltv_delta = 23;
6656 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6657 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6658 let route_params = RouteParameters::from_payment_params_and_value(
6659 fail_payment_params, 100);
6660 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6661 &Default::default(), &random_seed_bytes)
6663 Err(LightningError { err, .. } ) => {
6664 assert_eq!(err, "Failed to find a path to the given destination");
6666 Ok(_) => panic!("Expected error"),
6671 fn avoids_recently_failed_paths() {
6672 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6673 // randomly inserting channels into it until we can't find a route anymore.
6674 let (secp_ctx, network, _, _, logger) = build_graph();
6675 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6676 let network_graph = network.read_only();
6678 let scorer = ln_test_utils::TestScorer::new();
6679 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6680 .with_max_path_count(1);
6681 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6682 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6684 // We should be able to find a route initially, and then after we fail a few random
6685 // channels eventually we won't be able to any longer.
6686 let route_params = RouteParameters::from_payment_params_and_value(
6687 payment_params.clone(), 100);
6688 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6689 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6691 let route_params = RouteParameters::from_payment_params_and_value(
6692 payment_params.clone(), 100);
6693 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6694 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6696 for chan in route.paths[0].hops.iter() {
6697 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6699 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6700 % route.paths[0].hops.len();
6701 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6707 fn limits_path_length() {
6708 let (secp_ctx, network, _, _, logger) = build_line_graph();
6709 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6710 let network_graph = network.read_only();
6712 let scorer = ln_test_utils::TestScorer::new();
6713 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6714 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6716 // First check we can actually create a long route on this graph.
6717 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6718 let route_params = RouteParameters::from_payment_params_and_value(
6719 feasible_payment_params, 100);
6720 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6721 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6722 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6723 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6725 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6726 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6727 let route_params = RouteParameters::from_payment_params_and_value(
6728 fail_payment_params, 100);
6729 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6730 &Default::default(), &random_seed_bytes)
6732 Err(LightningError { err, .. } ) => {
6733 assert_eq!(err, "Failed to find a path to the given destination");
6735 Ok(_) => panic!("Expected error"),
6740 fn adds_and_limits_cltv_offset() {
6741 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6742 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6744 let scorer = ln_test_utils::TestScorer::new();
6746 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6747 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6748 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6749 let route_params = RouteParameters::from_payment_params_and_value(
6750 payment_params.clone(), 100);
6751 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6752 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6753 assert_eq!(route.paths.len(), 1);
6755 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6757 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6758 let mut route_default = route.clone();
6759 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6760 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6761 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6762 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6763 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6765 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6766 let mut route_limited = route.clone();
6767 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6768 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6769 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6770 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6771 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6775 fn adds_plausible_cltv_offset() {
6776 let (secp_ctx, network, _, _, logger) = build_graph();
6777 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6778 let network_graph = network.read_only();
6779 let network_nodes = network_graph.nodes();
6780 let network_channels = network_graph.channels();
6781 let scorer = ln_test_utils::TestScorer::new();
6782 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6783 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6784 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6786 let route_params = RouteParameters::from_payment_params_and_value(
6787 payment_params.clone(), 100);
6788 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6789 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6790 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6792 let mut path_plausibility = vec![];
6794 for p in route.paths {
6795 // 1. Select random observation point
6796 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6797 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6799 prng.process_in_place(&mut random_bytes);
6800 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6801 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6803 // 2. Calculate what CLTV expiry delta we would observe there
6804 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6806 // 3. Starting from the observation point, find candidate paths
6807 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6808 candidates.push_back((observation_point, vec![]));
6810 let mut found_plausible_candidate = false;
6812 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6813 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6814 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6815 found_plausible_candidate = true;
6816 break 'candidate_loop;
6820 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6821 for channel_id in &cur_node.channels {
6822 if let Some(channel_info) = network_channels.get(&channel_id) {
6823 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6824 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6825 if cur_path_cltv_deltas.iter().sum::<u32>()
6826 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6827 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6828 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6829 candidates.push_back((*next_id, new_path_cltv_deltas));
6837 path_plausibility.push(found_plausible_candidate);
6839 assert!(path_plausibility.iter().all(|x| *x));
6843 fn builds_correct_path_from_hops() {
6844 let (secp_ctx, network, _, _, logger) = build_graph();
6845 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6846 let network_graph = network.read_only();
6848 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6849 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6851 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6852 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6853 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6854 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6855 Arc::clone(&logger), &random_seed_bytes).unwrap();
6856 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6857 assert_eq!(hops.len(), route.paths[0].hops.len());
6858 for (idx, hop_pubkey) in hops.iter().enumerate() {
6859 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6864 fn avoids_saturating_channels() {
6865 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6866 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6867 let decay_params = ProbabilisticScoringDecayParameters::default();
6868 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6870 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6871 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6872 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6873 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6874 short_channel_id: 4,
6877 cltv_expiry_delta: (4 << 4) | 1,
6878 htlc_minimum_msat: 0,
6879 htlc_maximum_msat: 250_000_000,
6881 fee_proportional_millionths: 0,
6882 excess_data: Vec::new()
6884 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6885 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
6886 short_channel_id: 13,
6889 cltv_expiry_delta: (13 << 4) | 1,
6890 htlc_minimum_msat: 0,
6891 htlc_maximum_msat: 250_000_000,
6893 fee_proportional_millionths: 0,
6894 excess_data: Vec::new()
6897 let config = UserConfig::default();
6898 let payment_params = PaymentParameters::from_node_id(nodes[2], 42)
6899 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
6901 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6902 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6903 // 100,000 sats is less than the available liquidity on each channel, set above.
6904 let route_params = RouteParameters::from_payment_params_and_value(
6905 payment_params, 100_000_000);
6906 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6907 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6908 assert_eq!(route.paths.len(), 2);
6909 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6910 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6913 #[cfg(not(feature = "no-std"))]
6914 pub(super) fn random_init_seed() -> u64 {
6915 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6916 use core::hash::{BuildHasher, Hasher};
6917 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6918 println!("Using seed of {}", seed);
6923 #[cfg(not(feature = "no-std"))]
6924 fn generate_routes() {
6925 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6927 let logger = ln_test_utils::TestLogger::new();
6928 let graph = match super::bench_utils::read_network_graph(&logger) {
6936 let params = ProbabilisticScoringFeeParameters::default();
6937 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6938 let features = super::Bolt11InvoiceFeatures::empty();
6940 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6944 #[cfg(not(feature = "no-std"))]
6945 fn generate_routes_mpp() {
6946 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6948 let logger = ln_test_utils::TestLogger::new();
6949 let graph = match super::bench_utils::read_network_graph(&logger) {
6957 let params = ProbabilisticScoringFeeParameters::default();
6958 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6959 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6961 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6965 #[cfg(not(feature = "no-std"))]
6966 fn generate_large_mpp_routes() {
6967 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6969 let logger = ln_test_utils::TestLogger::new();
6970 let graph = match super::bench_utils::read_network_graph(&logger) {
6978 let params = ProbabilisticScoringFeeParameters::default();
6979 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6980 let features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
6982 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6986 fn honors_manual_penalties() {
6987 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6988 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6990 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6991 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6993 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6994 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6996 // First check set manual penalties are returned by the scorer.
6997 let usage = ChannelUsage {
6999 inflight_htlc_msat: 0,
7000 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
7002 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
7003 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
7004 let network_graph = network_graph.read_only();
7005 let channels = network_graph.channels();
7006 let channel = channels.get(&5).unwrap();
7007 let info = channel.as_directed_from(&NodeId::from_pubkey(&nodes[3])).unwrap();
7008 let candidate: CandidateRouteHop = CandidateRouteHop::PublicHop {
7010 short_channel_id: 5,
7012 assert_eq!(scorer.channel_penalty_msat(&candidate, usage, &scorer_params), 456);
7014 // Then check we can get a normal route
7015 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
7016 let route_params = RouteParameters::from_payment_params_and_value(
7017 payment_params, 100);
7018 let route = get_route(&our_id, &route_params, &network_graph, None,
7019 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
7020 assert!(route.is_ok());
7022 // Then check that we can't get a route if we ban an intermediate node.
7023 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
7024 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
7025 assert!(route.is_err());
7027 // Finally make sure we can route again, when we remove the ban.
7028 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
7029 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
7030 assert!(route.is_ok());
7034 fn abide_by_route_hint_max_htlc() {
7035 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
7036 // params in the final route.
7037 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7038 let netgraph = network_graph.read_only();
7039 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7040 let scorer = ln_test_utils::TestScorer::new();
7041 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7042 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7043 let config = UserConfig::default();
7045 let max_htlc_msat = 50_000;
7046 let route_hint_1 = RouteHint(vec![RouteHintHop {
7047 src_node_id: nodes[2],
7048 short_channel_id: 42,
7051 proportional_millionths: 0,
7053 cltv_expiry_delta: 10,
7054 htlc_minimum_msat: None,
7055 htlc_maximum_msat: Some(max_htlc_msat),
7057 let dest_node_id = ln_test_utils::pubkey(42);
7058 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7059 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
7060 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7063 // Make sure we'll error if our route hints don't have enough liquidity according to their
7064 // htlc_maximum_msat.
7065 let mut route_params = RouteParameters::from_payment_params_and_value(
7066 payment_params, max_htlc_msat + 1);
7067 route_params.max_total_routing_fee_msat = None;
7068 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
7069 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
7072 assert_eq!(err, "Failed to find a sufficient route to the given destination");
7073 } else { panic!(); }
7075 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
7076 let mut route_hint_2 = route_hint_1.clone();
7077 route_hint_2.0[0].short_channel_id = 43;
7078 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7079 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7080 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7082 let mut route_params = RouteParameters::from_payment_params_and_value(
7083 payment_params, max_htlc_msat + 1);
7084 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
7085 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
7086 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7087 assert_eq!(route.paths.len(), 2);
7088 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7089 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7093 fn direct_channel_to_hints_with_max_htlc() {
7094 // Check that if we have a first hop channel peer that's connected to multiple provided route
7095 // hints, that we properly split the payment between the route hints if needed.
7096 let logger = Arc::new(ln_test_utils::TestLogger::new());
7097 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7098 let scorer = ln_test_utils::TestScorer::new();
7099 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7100 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7101 let config = UserConfig::default();
7103 let our_node_id = ln_test_utils::pubkey(42);
7104 let intermed_node_id = ln_test_utils::pubkey(43);
7105 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7107 let amt_msat = 900_000;
7108 let max_htlc_msat = 500_000;
7109 let route_hint_1 = RouteHint(vec![RouteHintHop {
7110 src_node_id: intermed_node_id,
7111 short_channel_id: 44,
7114 proportional_millionths: 0,
7116 cltv_expiry_delta: 10,
7117 htlc_minimum_msat: None,
7118 htlc_maximum_msat: Some(max_htlc_msat),
7120 src_node_id: intermed_node_id,
7121 short_channel_id: 45,
7124 proportional_millionths: 0,
7126 cltv_expiry_delta: 10,
7127 htlc_minimum_msat: None,
7128 // Check that later route hint max htlcs don't override earlier ones
7129 htlc_maximum_msat: Some(max_htlc_msat - 50),
7131 let mut route_hint_2 = route_hint_1.clone();
7132 route_hint_2.0[0].short_channel_id = 46;
7133 route_hint_2.0[1].short_channel_id = 47;
7134 let dest_node_id = ln_test_utils::pubkey(44);
7135 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
7136 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
7137 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config))
7140 let route_params = RouteParameters::from_payment_params_and_value(
7141 payment_params, amt_msat);
7142 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7143 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7144 &Default::default(), &random_seed_bytes).unwrap();
7145 assert_eq!(route.paths.len(), 2);
7146 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7147 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7148 assert_eq!(route.get_total_amount(), amt_msat);
7150 // Re-run but with two first hop channels connected to the same route hint peers that must be
7152 let first_hops = vec![
7153 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7154 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
7156 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7157 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7158 &Default::default(), &random_seed_bytes).unwrap();
7159 assert_eq!(route.paths.len(), 2);
7160 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7161 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7162 assert_eq!(route.get_total_amount(), amt_msat);
7164 // Make sure this works for blinded route hints.
7165 let blinded_path = BlindedPath {
7166 introduction_node_id: intermed_node_id,
7167 blinding_point: ln_test_utils::pubkey(42),
7169 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
7170 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
7173 let blinded_payinfo = BlindedPayInfo {
7175 fee_proportional_millionths: 0,
7176 htlc_minimum_msat: 1,
7177 htlc_maximum_msat: max_htlc_msat,
7178 cltv_expiry_delta: 10,
7179 features: BlindedHopFeatures::empty(),
7181 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7182 let payment_params = PaymentParameters::blinded(vec![
7183 (blinded_payinfo.clone(), blinded_path.clone()),
7184 (blinded_payinfo.clone(), blinded_path.clone())])
7185 .with_bolt12_features(bolt12_features).unwrap();
7186 let route_params = RouteParameters::from_payment_params_and_value(
7187 payment_params, amt_msat);
7188 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
7189 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7190 &Default::default(), &random_seed_bytes).unwrap();
7191 assert_eq!(route.paths.len(), 2);
7192 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
7193 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
7194 assert_eq!(route.get_total_amount(), amt_msat);
7198 fn blinded_route_ser() {
7199 let blinded_path_1 = BlindedPath {
7200 introduction_node_id: ln_test_utils::pubkey(42),
7201 blinding_point: ln_test_utils::pubkey(43),
7203 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
7204 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
7207 let blinded_path_2 = BlindedPath {
7208 introduction_node_id: ln_test_utils::pubkey(46),
7209 blinding_point: ln_test_utils::pubkey(47),
7211 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
7212 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
7215 // (De)serialize a Route with 1 blinded path out of two total paths.
7216 let mut route = Route { paths: vec![Path {
7217 hops: vec![RouteHop {
7218 pubkey: ln_test_utils::pubkey(50),
7219 node_features: NodeFeatures::empty(),
7220 short_channel_id: 42,
7221 channel_features: ChannelFeatures::empty(),
7223 cltv_expiry_delta: 0,
7224 maybe_announced_channel: true,
7226 blinded_tail: Some(BlindedTail {
7227 hops: blinded_path_1.blinded_hops,
7228 blinding_point: blinded_path_1.blinding_point,
7229 excess_final_cltv_expiry_delta: 40,
7230 final_value_msat: 100,
7232 hops: vec![RouteHop {
7233 pubkey: ln_test_utils::pubkey(51),
7234 node_features: NodeFeatures::empty(),
7235 short_channel_id: 43,
7236 channel_features: ChannelFeatures::empty(),
7238 cltv_expiry_delta: 0,
7239 maybe_announced_channel: true,
7240 }], blinded_tail: None }],
7243 let encoded_route = route.encode();
7244 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7245 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7246 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7248 // (De)serialize a Route with two paths, each containing a blinded tail.
7249 route.paths[1].blinded_tail = Some(BlindedTail {
7250 hops: blinded_path_2.blinded_hops,
7251 blinding_point: blinded_path_2.blinding_point,
7252 excess_final_cltv_expiry_delta: 41,
7253 final_value_msat: 101,
7255 let encoded_route = route.encode();
7256 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
7257 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
7258 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
7262 fn blinded_path_inflight_processing() {
7263 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
7264 // account for the blinded tail's final amount_msat.
7265 let mut inflight_htlcs = InFlightHtlcs::new();
7266 let blinded_path = BlindedPath {
7267 introduction_node_id: ln_test_utils::pubkey(43),
7268 blinding_point: ln_test_utils::pubkey(48),
7269 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
7272 hops: vec![RouteHop {
7273 pubkey: ln_test_utils::pubkey(42),
7274 node_features: NodeFeatures::empty(),
7275 short_channel_id: 42,
7276 channel_features: ChannelFeatures::empty(),
7278 cltv_expiry_delta: 0,
7279 maybe_announced_channel: false,
7282 pubkey: blinded_path.introduction_node_id,
7283 node_features: NodeFeatures::empty(),
7284 short_channel_id: 43,
7285 channel_features: ChannelFeatures::empty(),
7287 cltv_expiry_delta: 0,
7288 maybe_announced_channel: false,
7290 blinded_tail: Some(BlindedTail {
7291 hops: blinded_path.blinded_hops,
7292 blinding_point: blinded_path.blinding_point,
7293 excess_final_cltv_expiry_delta: 0,
7294 final_value_msat: 200,
7297 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
7298 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
7299 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
7303 fn blinded_path_cltv_shadow_offset() {
7304 // Make sure we add a shadow offset when sending to blinded paths.
7305 let blinded_path = BlindedPath {
7306 introduction_node_id: ln_test_utils::pubkey(43),
7307 blinding_point: ln_test_utils::pubkey(44),
7309 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
7310 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
7313 let mut route = Route { paths: vec![Path {
7314 hops: vec![RouteHop {
7315 pubkey: ln_test_utils::pubkey(42),
7316 node_features: NodeFeatures::empty(),
7317 short_channel_id: 42,
7318 channel_features: ChannelFeatures::empty(),
7320 cltv_expiry_delta: 0,
7321 maybe_announced_channel: false,
7324 pubkey: blinded_path.introduction_node_id,
7325 node_features: NodeFeatures::empty(),
7326 short_channel_id: 43,
7327 channel_features: ChannelFeatures::empty(),
7329 cltv_expiry_delta: 0,
7330 maybe_announced_channel: false,
7333 blinded_tail: Some(BlindedTail {
7334 hops: blinded_path.blinded_hops,
7335 blinding_point: blinded_path.blinding_point,
7336 excess_final_cltv_expiry_delta: 0,
7337 final_value_msat: 200,
7339 }], route_params: None};
7341 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
7342 let (_, network_graph, _, _, _) = build_line_graph();
7343 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
7344 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
7345 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
7349 fn simple_blinded_route_hints() {
7350 do_simple_blinded_route_hints(1);
7351 do_simple_blinded_route_hints(2);
7352 do_simple_blinded_route_hints(3);
7355 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
7356 // Check that we can generate a route to a blinded path with the expected hops.
7357 let (secp_ctx, network, _, _, logger) = build_graph();
7358 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7359 let network_graph = network.read_only();
7361 let scorer = ln_test_utils::TestScorer::new();
7362 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7363 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7365 let mut blinded_path = BlindedPath {
7366 introduction_node_id: nodes[2],
7367 blinding_point: ln_test_utils::pubkey(42),
7368 blinded_hops: Vec::with_capacity(num_blinded_hops),
7370 for i in 0..num_blinded_hops {
7371 blinded_path.blinded_hops.push(
7372 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
7375 let blinded_payinfo = BlindedPayInfo {
7377 fee_proportional_millionths: 500,
7378 htlc_minimum_msat: 1000,
7379 htlc_maximum_msat: 100_000_000,
7380 cltv_expiry_delta: 15,
7381 features: BlindedHopFeatures::empty(),
7384 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
7385 let route_params = RouteParameters::from_payment_params_and_value(
7386 payment_params, 1001);
7387 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7388 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7389 assert_eq!(route.paths.len(), 1);
7390 assert_eq!(route.paths[0].hops.len(), 2);
7392 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
7393 assert_eq!(tail.hops, blinded_path.blinded_hops);
7394 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
7395 assert_eq!(tail.final_value_msat, 1001);
7397 let final_hop = route.paths[0].hops.last().unwrap();
7398 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
7399 if tail.hops.len() > 1 {
7400 assert_eq!(final_hop.fee_msat,
7401 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
7402 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7404 assert_eq!(final_hop.fee_msat, 0);
7405 assert_eq!(final_hop.cltv_expiry_delta, 0);
7410 fn blinded_path_routing_errors() {
7411 // Check that we can generate a route to a blinded path with the expected hops.
7412 let (secp_ctx, network, _, _, logger) = build_graph();
7413 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7414 let network_graph = network.read_only();
7416 let scorer = ln_test_utils::TestScorer::new();
7417 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7418 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7420 let mut invalid_blinded_path = BlindedPath {
7421 introduction_node_id: nodes[2],
7422 blinding_point: ln_test_utils::pubkey(42),
7424 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7427 let blinded_payinfo = BlindedPayInfo {
7429 fee_proportional_millionths: 500,
7430 htlc_minimum_msat: 1000,
7431 htlc_maximum_msat: 100_000_000,
7432 cltv_expiry_delta: 15,
7433 features: BlindedHopFeatures::empty(),
7436 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7437 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7438 let payment_params = PaymentParameters::blinded(vec![
7439 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7440 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7441 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7442 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7443 &scorer, &Default::default(), &random_seed_bytes)
7445 Err(LightningError { err, .. }) => {
7446 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7448 _ => panic!("Expected error")
7451 invalid_blinded_path.introduction_node_id = our_id;
7452 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7453 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7454 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7455 &Default::default(), &random_seed_bytes)
7457 Err(LightningError { err, .. }) => {
7458 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7460 _ => panic!("Expected error")
7463 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7464 invalid_blinded_path.blinded_hops.clear();
7465 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7466 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7467 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7468 &Default::default(), &random_seed_bytes)
7470 Err(LightningError { err, .. }) => {
7471 assert_eq!(err, "0-hop blinded path provided");
7473 _ => panic!("Expected error")
7478 fn matching_intro_node_paths_provided() {
7479 // Check that if multiple blinded paths with the same intro node are provided in payment
7480 // parameters, we'll return the correct paths in the resulting MPP route.
7481 let (secp_ctx, network, _, _, logger) = build_graph();
7482 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7483 let network_graph = network.read_only();
7485 let scorer = ln_test_utils::TestScorer::new();
7486 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7487 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7488 let config = UserConfig::default();
7490 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7491 let blinded_path_1 = BlindedPath {
7492 introduction_node_id: nodes[2],
7493 blinding_point: ln_test_utils::pubkey(42),
7495 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7496 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7499 let blinded_payinfo_1 = BlindedPayInfo {
7501 fee_proportional_millionths: 0,
7502 htlc_minimum_msat: 0,
7503 htlc_maximum_msat: 30_000,
7504 cltv_expiry_delta: 0,
7505 features: BlindedHopFeatures::empty(),
7508 let mut blinded_path_2 = blinded_path_1.clone();
7509 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7510 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7511 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7513 let blinded_hints = vec![
7514 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7515 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7517 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7518 .with_bolt12_features(bolt12_features).unwrap();
7520 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7521 route_params.max_total_routing_fee_msat = Some(100_000);
7522 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7523 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7524 assert_eq!(route.paths.len(), 2);
7525 let mut total_amount_paid_msat = 0;
7526 for path in route.paths.into_iter() {
7527 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7528 if let Some(bt) = &path.blinded_tail {
7529 assert_eq!(bt.blinding_point,
7530 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7531 .map(|(_, bp)| bp.blinding_point).unwrap());
7532 } else { panic!(); }
7533 total_amount_paid_msat += path.final_value_msat();
7535 assert_eq!(total_amount_paid_msat, 100_000);
7539 fn direct_to_intro_node() {
7540 // This previously caused a debug panic in the router when asserting
7541 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7542 // direct channels we failed to account for the fee charged for use of the blinded path.
7545 // node0 -1(1)2 - node1
7546 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7547 // doesn't account for the blinded path fee.
7549 let secp_ctx = Secp256k1::new();
7550 let logger = Arc::new(ln_test_utils::TestLogger::new());
7551 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7552 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7553 let scorer = ln_test_utils::TestScorer::new();
7554 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7555 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7557 let amt_msat = 10_000_000;
7558 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7559 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7560 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7561 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7562 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7563 short_channel_id: 1,
7566 cltv_expiry_delta: 42,
7567 htlc_minimum_msat: 1_000,
7568 htlc_maximum_msat: 10_000_000,
7570 fee_proportional_millionths: 0,
7571 excess_data: Vec::new()
7573 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7574 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7575 short_channel_id: 1,
7578 cltv_expiry_delta: 42,
7579 htlc_minimum_msat: 1_000,
7580 htlc_maximum_msat: 10_000_000,
7582 fee_proportional_millionths: 0,
7583 excess_data: Vec::new()
7585 let first_hops = vec![
7586 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7588 let blinded_path = BlindedPath {
7589 introduction_node_id: nodes[1],
7590 blinding_point: ln_test_utils::pubkey(42),
7592 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7593 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7596 let blinded_payinfo = BlindedPayInfo {
7597 fee_base_msat: 1000,
7598 fee_proportional_millionths: 0,
7599 htlc_minimum_msat: 1000,
7600 htlc_maximum_msat: MAX_VALUE_MSAT,
7601 cltv_expiry_delta: 0,
7602 features: BlindedHopFeatures::empty(),
7604 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7606 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7608 let netgraph = network_graph.read_only();
7609 let route_params = RouteParameters::from_payment_params_and_value(
7610 payment_params.clone(), amt_msat);
7611 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7612 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7613 &Default::default(), &random_seed_bytes) {
7614 assert_eq!(err, "Failed to find a path to the given destination");
7615 } else { panic!("Expected error") }
7617 // Sending an exact amount accounting for the blinded path fee works.
7618 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7619 let route_params = RouteParameters::from_payment_params_and_value(
7620 payment_params, amt_minus_blinded_path_fee);
7621 let route = get_route(&nodes[0], &route_params, &netgraph,
7622 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7623 &Default::default(), &random_seed_bytes).unwrap();
7624 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7625 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7629 fn direct_to_matching_intro_nodes() {
7630 // This previously caused us to enter `unreachable` code in the following situation:
7631 // 1. We add a route candidate for intro_node contributing a high amount
7632 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7633 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7634 // amount, and update our route candidate for intro_node for the lower amount
7635 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7636 // lower contribution amount, but fail (this was previously caused by failure to account for
7637 // blinded path fees when adding first_hop<>intro_node candidates)
7638 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7639 // candidate still thinks its path is contributing the original higher amount. This caused us
7640 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7642 let secp_ctx = Secp256k1::new();
7643 let logger = Arc::new(ln_test_utils::TestLogger::new());
7644 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7645 let scorer = ln_test_utils::TestScorer::new();
7646 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7647 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7648 let config = UserConfig::default();
7650 // Values are taken from the fuzz input that uncovered this panic.
7651 let amt_msat = 21_7020_5185_1403_2640;
7652 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7653 let first_hops = vec![
7654 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7655 18446744073709551615)];
7657 let blinded_path = BlindedPath {
7658 introduction_node_id: nodes[1],
7659 blinding_point: ln_test_utils::pubkey(42),
7661 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7662 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7665 let blinded_payinfo = BlindedPayInfo {
7666 fee_base_msat: 5046_2720,
7667 fee_proportional_millionths: 0,
7668 htlc_minimum_msat: 4503_5996_2737_0496,
7669 htlc_maximum_msat: 45_0359_9627_3704_9600,
7670 cltv_expiry_delta: 0,
7671 features: BlindedHopFeatures::empty(),
7673 let mut blinded_hints = vec![
7674 (blinded_payinfo.clone(), blinded_path.clone()),
7675 (blinded_payinfo.clone(), blinded_path.clone()),
7677 blinded_hints[1].0.fee_base_msat = 419_4304;
7678 blinded_hints[1].0.fee_proportional_millionths = 257;
7679 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7680 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7681 blinded_hints[1].0.cltv_expiry_delta = 0;
7683 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7684 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7685 .with_bolt12_features(bolt12_features).unwrap();
7687 let netgraph = network_graph.read_only();
7688 let route_params = RouteParameters::from_payment_params_and_value(
7689 payment_params, amt_msat);
7690 let route = get_route(&nodes[0], &route_params, &netgraph,
7691 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7692 &Default::default(), &random_seed_bytes).unwrap();
7693 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7694 assert_eq!(route.get_total_amount(), amt_msat);
7698 fn we_are_intro_node_candidate_hops() {
7699 // This previously led to a panic in the router because we'd generate a Path with only a
7700 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7701 // where the origin node is the intro node. We now fully disallow considering candidate hops
7702 // where the origin node is the intro node.
7703 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7704 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7705 let scorer = ln_test_utils::TestScorer::new();
7706 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7707 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7708 let config = UserConfig::default();
7710 // Values are taken from the fuzz input that uncovered this panic.
7711 let amt_msat = 21_7020_5185_1423_0019;
7713 let blinded_path = BlindedPath {
7714 introduction_node_id: our_id,
7715 blinding_point: ln_test_utils::pubkey(42),
7717 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7718 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7721 let blinded_payinfo = BlindedPayInfo {
7722 fee_base_msat: 5052_9027,
7723 fee_proportional_millionths: 0,
7724 htlc_minimum_msat: 21_7020_5185_1423_0019,
7725 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7726 cltv_expiry_delta: 0,
7727 features: BlindedHopFeatures::empty(),
7729 let mut blinded_hints = vec![
7730 (blinded_payinfo.clone(), blinded_path.clone()),
7731 (blinded_payinfo.clone(), blinded_path.clone()),
7733 blinded_hints[1].1.introduction_node_id = nodes[6];
7735 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7736 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7737 .with_bolt12_features(bolt12_features.clone()).unwrap();
7739 let netgraph = network_graph.read_only();
7740 let route_params = RouteParameters::from_payment_params_and_value(
7741 payment_params, amt_msat);
7742 if let Err(LightningError { err, .. }) = get_route(
7743 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7745 assert_eq!(err, "Failed to find a path to the given destination");
7750 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7751 // This previously led to a debug panic in the router because we'd find an invalid Path with
7752 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7753 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7754 // the payment, when it was intended to only include the final value of the payment.
7755 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7756 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7757 let scorer = ln_test_utils::TestScorer::new();
7758 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7759 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7760 let config = UserConfig::default();
7762 // Values are taken from the fuzz input that uncovered this panic.
7763 let amt_msat = 21_7020_5185_1423_0019;
7765 let blinded_path = BlindedPath {
7766 introduction_node_id: our_id,
7767 blinding_point: ln_test_utils::pubkey(42),
7769 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7770 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7773 let blinded_payinfo = BlindedPayInfo {
7774 fee_base_msat: 10_4425_1395,
7775 fee_proportional_millionths: 0,
7776 htlc_minimum_msat: 21_7301_9934_9094_0931,
7777 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7778 cltv_expiry_delta: 0,
7779 features: BlindedHopFeatures::empty(),
7781 let mut blinded_hints = vec![
7782 (blinded_payinfo.clone(), blinded_path.clone()),
7783 (blinded_payinfo.clone(), blinded_path.clone()),
7784 (blinded_payinfo.clone(), blinded_path.clone()),
7786 blinded_hints[1].0.fee_base_msat = 5052_9027;
7787 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7788 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7790 blinded_hints[2].1.introduction_node_id = nodes[6];
7792 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7793 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7794 .with_bolt12_features(bolt12_features.clone()).unwrap();
7796 let netgraph = network_graph.read_only();
7797 let route_params = RouteParameters::from_payment_params_and_value(
7798 payment_params, amt_msat);
7799 if let Err(LightningError { err, .. }) = get_route(
7800 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7802 assert_eq!(err, "Failed to find a path to the given destination");
7807 fn min_htlc_overpay_violates_max_htlc() {
7808 do_min_htlc_overpay_violates_max_htlc(true);
7809 do_min_htlc_overpay_violates_max_htlc(false);
7811 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7812 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7813 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7814 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7815 // that the used liquidity for a hop was less than its available liquidity limit.
7816 let secp_ctx = Secp256k1::new();
7817 let logger = Arc::new(ln_test_utils::TestLogger::new());
7818 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7819 let scorer = ln_test_utils::TestScorer::new();
7820 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7821 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7822 let config = UserConfig::default();
7824 // Values are taken from the fuzz input that uncovered this panic.
7825 let amt_msat = 7_4009_8048;
7826 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7827 let first_hop_outbound_capacity = 2_7345_2000;
7828 let first_hops = vec![get_channel_details(
7829 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7830 first_hop_outbound_capacity
7833 let base_fee = 1_6778_3453;
7834 let htlc_min = 2_5165_8240;
7835 let payment_params = if blinded_payee {
7836 let blinded_path = BlindedPath {
7837 introduction_node_id: nodes[0],
7838 blinding_point: ln_test_utils::pubkey(42),
7840 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7841 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7844 let blinded_payinfo = BlindedPayInfo {
7845 fee_base_msat: base_fee,
7846 fee_proportional_millionths: 0,
7847 htlc_minimum_msat: htlc_min,
7848 htlc_maximum_msat: htlc_min * 1000,
7849 cltv_expiry_delta: 0,
7850 features: BlindedHopFeatures::empty(),
7852 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7853 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7854 .with_bolt12_features(bolt12_features.clone()).unwrap()
7856 let route_hint = RouteHint(vec![RouteHintHop {
7857 src_node_id: nodes[0],
7858 short_channel_id: 42,
7860 base_msat: base_fee,
7861 proportional_millionths: 0,
7863 cltv_expiry_delta: 10,
7864 htlc_minimum_msat: Some(htlc_min),
7865 htlc_maximum_msat: None,
7868 PaymentParameters::from_node_id(nodes[1], 42)
7869 .with_route_hints(vec![route_hint]).unwrap()
7870 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7873 let netgraph = network_graph.read_only();
7874 let route_params = RouteParameters::from_payment_params_and_value(
7875 payment_params, amt_msat);
7876 if let Err(LightningError { err, .. }) = get_route(
7877 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7878 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7880 assert_eq!(err, "Failed to find a path to the given destination");
7885 fn previously_used_liquidity_violates_max_htlc() {
7886 do_previously_used_liquidity_violates_max_htlc(true);
7887 do_previously_used_liquidity_violates_max_htlc(false);
7890 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7891 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7892 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7893 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7894 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7895 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7896 let secp_ctx = Secp256k1::new();
7897 let logger = Arc::new(ln_test_utils::TestLogger::new());
7898 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7899 let scorer = ln_test_utils::TestScorer::new();
7900 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7901 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7902 let config = UserConfig::default();
7904 // Values are taken from the fuzz input that uncovered this panic.
7905 let amt_msat = 52_4288;
7906 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7907 let first_hops = vec![get_channel_details(
7908 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7909 ), get_channel_details(
7910 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7913 let base_fees = [0, 425_9840, 0, 0];
7914 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7915 let payment_params = if blinded_payee {
7916 let blinded_path = BlindedPath {
7917 introduction_node_id: nodes[0],
7918 blinding_point: ln_test_utils::pubkey(42),
7920 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7921 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7924 let mut blinded_hints = Vec::new();
7925 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7926 blinded_hints.push((BlindedPayInfo {
7927 fee_base_msat: *base_fee,
7928 fee_proportional_millionths: 0,
7929 htlc_minimum_msat: *htlc_min,
7930 htlc_maximum_msat: htlc_min * 100,
7931 cltv_expiry_delta: 10,
7932 features: BlindedHopFeatures::empty(),
7933 }, blinded_path.clone()));
7935 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
7936 PaymentParameters::blinded(blinded_hints.clone())
7937 .with_bolt12_features(bolt12_features.clone()).unwrap()
7939 let mut route_hints = Vec::new();
7940 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7941 route_hints.push(RouteHint(vec![RouteHintHop {
7942 src_node_id: nodes[0],
7943 short_channel_id: 42 + idx as u64,
7945 base_msat: *base_fee,
7946 proportional_millionths: 0,
7948 cltv_expiry_delta: 10,
7949 htlc_minimum_msat: Some(*htlc_min),
7950 htlc_maximum_msat: Some(htlc_min * 100),
7953 PaymentParameters::from_node_id(nodes[1], 42)
7954 .with_route_hints(route_hints).unwrap()
7955 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap()
7958 let netgraph = network_graph.read_only();
7959 let route_params = RouteParameters::from_payment_params_and_value(
7960 payment_params, amt_msat);
7962 let route = get_route(
7963 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7964 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes
7966 assert_eq!(route.paths.len(), 1);
7967 assert_eq!(route.get_total_amount(), amt_msat);
7971 fn candidate_path_min() {
7972 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7973 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7974 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7975 // would add a connecting first_hop node that did not have enough contribution amount, leading
7976 // to a debug panic upon invalid path construction.
7977 let secp_ctx = Secp256k1::new();
7978 let logger = Arc::new(ln_test_utils::TestLogger::new());
7979 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7980 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7981 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7982 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7983 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7984 let config = UserConfig::default();
7986 // Values are taken from the fuzz input that uncovered this panic.
7987 let amt_msat = 7_4009_8048;
7988 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7989 let first_hops = vec![get_channel_details(
7990 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7993 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7994 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7995 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
7996 short_channel_id: 6,
7999 cltv_expiry_delta: (6 << 4) | 0,
8000 htlc_minimum_msat: 0,
8001 htlc_maximum_msat: MAX_VALUE_MSAT,
8003 fee_proportional_millionths: 0,
8004 excess_data: Vec::new()
8006 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
8008 let htlc_min = 2_5165_8240;
8009 let blinded_hints = vec![
8011 fee_base_msat: 1_6778_3453,
8012 fee_proportional_millionths: 0,
8013 htlc_minimum_msat: htlc_min,
8014 htlc_maximum_msat: htlc_min * 100,
8015 cltv_expiry_delta: 10,
8016 features: BlindedHopFeatures::empty(),
8018 introduction_node_id: nodes[0],
8019 blinding_point: ln_test_utils::pubkey(42),
8021 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8022 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8026 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8027 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
8028 .with_bolt12_features(bolt12_features.clone()).unwrap();
8029 let route_params = RouteParameters::from_payment_params_and_value(
8030 payment_params, amt_msat);
8031 let netgraph = network_graph.read_only();
8033 if let Err(LightningError { err, .. }) = get_route(
8034 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8035 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8038 assert_eq!(err, "Failed to find a path to the given destination");
8043 fn path_contribution_includes_min_htlc_overpay() {
8044 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
8045 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
8046 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
8047 // selection, both tested here.
8048 let secp_ctx = Secp256k1::new();
8049 let logger = Arc::new(ln_test_utils::TestLogger::new());
8050 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8051 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
8052 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8053 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8054 let config = UserConfig::default();
8056 // Values are taken from the fuzz input that uncovered this panic.
8057 let amt_msat = 562_0000;
8058 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
8059 let first_hops = vec![
8060 get_channel_details(
8061 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
8065 let htlc_mins = [49_0000, 1125_0000];
8066 let payment_params = {
8067 let blinded_path = BlindedPath {
8068 introduction_node_id: nodes[0],
8069 blinding_point: ln_test_utils::pubkey(42),
8071 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
8072 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
8075 let mut blinded_hints = Vec::new();
8076 for htlc_min in htlc_mins.iter() {
8077 blinded_hints.push((BlindedPayInfo {
8079 fee_proportional_millionths: 0,
8080 htlc_minimum_msat: *htlc_min,
8081 htlc_maximum_msat: *htlc_min * 100,
8082 cltv_expiry_delta: 10,
8083 features: BlindedHopFeatures::empty(),
8084 }, blinded_path.clone()));
8086 let bolt12_features = channelmanager::provided_bolt12_invoice_features(&config);
8087 PaymentParameters::blinded(blinded_hints.clone())
8088 .with_bolt12_features(bolt12_features.clone()).unwrap()
8091 let netgraph = network_graph.read_only();
8092 let route_params = RouteParameters::from_payment_params_and_value(
8093 payment_params, amt_msat);
8094 let route = get_route(
8095 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
8096 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
8099 assert_eq!(route.paths.len(), 1);
8100 assert_eq!(route.get_total_amount(), amt_msat);
8104 fn first_hop_preferred_over_hint() {
8105 // Check that if we have a first hop to a peer we'd always prefer that over a route hint
8106 // they gave us, but we'd still consider all subsequent hints if they are more attractive.
8107 let secp_ctx = Secp256k1::new();
8108 let logger = Arc::new(ln_test_utils::TestLogger::new());
8109 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8110 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
8111 let scorer = ln_test_utils::TestScorer::new();
8112 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8113 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8114 let config = UserConfig::default();
8116 let amt_msat = 1_000_000;
8117 let (our_privkey, our_node_id, privkeys, nodes) = get_nodes(&secp_ctx);
8119 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0],
8120 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
8121 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
8122 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8123 short_channel_id: 1,
8126 cltv_expiry_delta: 42,
8127 htlc_minimum_msat: 1_000,
8128 htlc_maximum_msat: 10_000_000,
8130 fee_proportional_millionths: 0,
8131 excess_data: Vec::new()
8133 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8134 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8135 short_channel_id: 1,
8138 cltv_expiry_delta: 42,
8139 htlc_minimum_msat: 1_000,
8140 htlc_maximum_msat: 10_000_000,
8142 fee_proportional_millionths: 0,
8143 excess_data: Vec::new()
8146 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
8147 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 2);
8148 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
8149 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8150 short_channel_id: 2,
8153 cltv_expiry_delta: 42,
8154 htlc_minimum_msat: 1_000,
8155 htlc_maximum_msat: 10_000_000,
8157 fee_proportional_millionths: 0,
8158 excess_data: Vec::new()
8160 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
8161 chain_hash: ChainHash::using_genesis_block(Network::Testnet),
8162 short_channel_id: 2,
8165 cltv_expiry_delta: 42,
8166 htlc_minimum_msat: 1_000,
8167 htlc_maximum_msat: 10_000_000,
8169 fee_proportional_millionths: 0,
8170 excess_data: Vec::new()
8173 let dest_node_id = nodes[2];
8175 let route_hint = RouteHint(vec![RouteHintHop {
8176 src_node_id: our_node_id,
8177 short_channel_id: 44,
8180 proportional_millionths: 0,
8182 cltv_expiry_delta: 10,
8183 htlc_minimum_msat: None,
8184 htlc_maximum_msat: Some(5_000_000),
8187 src_node_id: nodes[0],
8188 short_channel_id: 45,
8191 proportional_millionths: 0,
8193 cltv_expiry_delta: 10,
8194 htlc_minimum_msat: None,
8195 htlc_maximum_msat: None,
8198 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8199 .with_route_hints(vec![route_hint]).unwrap()
8200 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8201 let route_params = RouteParameters::from_payment_params_and_value(
8202 payment_params, amt_msat);
8204 // First create an insufficient first hop for channel with SCID 1 and check we'd use the
8206 let first_hop = get_channel_details(Some(1), nodes[0],
8207 channelmanager::provided_init_features(&config), 999_999);
8208 let first_hops = vec![first_hop];
8210 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8211 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8212 &Default::default(), &random_seed_bytes).unwrap();
8213 assert_eq!(route.paths.len(), 1);
8214 assert_eq!(route.get_total_amount(), amt_msat);
8215 assert_eq!(route.paths[0].hops.len(), 2);
8216 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8217 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8218 assert_eq!(route.get_total_fees(), 123);
8220 // Now check we would trust our first hop info, i.e., fail if we detect the route hint is
8221 // for a first hop channel.
8222 let mut first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 999_999);
8223 first_hop.outbound_scid_alias = Some(44);
8224 let first_hops = vec![first_hop];
8226 let route_res = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8227 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8228 &Default::default(), &random_seed_bytes);
8229 assert!(route_res.is_err());
8231 // Finally check we'd use the first hop if has sufficient outbound capacity. But we'd stil
8232 // use the cheaper second hop of the route hint.
8233 let mut first_hop = get_channel_details(Some(1), nodes[0],
8234 channelmanager::provided_init_features(&config), 10_000_000);
8235 first_hop.outbound_scid_alias = Some(44);
8236 let first_hops = vec![first_hop];
8238 let route = get_route(&our_node_id, &route_params.clone(), &network_graph.read_only(),
8239 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8240 &Default::default(), &random_seed_bytes).unwrap();
8241 assert_eq!(route.paths.len(), 1);
8242 assert_eq!(route.get_total_amount(), amt_msat);
8243 assert_eq!(route.paths[0].hops.len(), 2);
8244 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
8245 assert_eq!(route.paths[0].hops[1].short_channel_id, 45);
8246 assert_eq!(route.get_total_fees(), 123);
8250 fn allow_us_being_first_hint() {
8251 // Check that we consider a route hint even if we are the src of the first hop.
8252 let secp_ctx = Secp256k1::new();
8253 let logger = Arc::new(ln_test_utils::TestLogger::new());
8254 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
8255 let scorer = ln_test_utils::TestScorer::new();
8256 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
8257 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8258 let config = UserConfig::default();
8260 let (_, our_node_id, _, nodes) = get_nodes(&secp_ctx);
8262 let amt_msat = 1_000_000;
8263 let dest_node_id = nodes[1];
8265 let first_hop = get_channel_details(Some(1), nodes[0], channelmanager::provided_init_features(&config), 10_000_000);
8266 let first_hops = vec![first_hop];
8268 let route_hint = RouteHint(vec![RouteHintHop {
8269 src_node_id: our_node_id,
8270 short_channel_id: 44,
8273 proportional_millionths: 0,
8275 cltv_expiry_delta: 10,
8276 htlc_minimum_msat: None,
8277 htlc_maximum_msat: None,
8280 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
8281 .with_route_hints(vec![route_hint]).unwrap()
8282 .with_bolt11_features(channelmanager::provided_bolt11_invoice_features(&config)).unwrap();
8284 let route_params = RouteParameters::from_payment_params_and_value(
8285 payment_params, amt_msat);
8288 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
8289 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
8290 &Default::default(), &random_seed_bytes).unwrap();
8292 assert_eq!(route.paths.len(), 1);
8293 assert_eq!(route.get_total_amount(), amt_msat);
8294 assert_eq!(route.get_total_fees(), 0);
8295 assert_eq!(route.paths[0].hops.len(), 1);
8297 assert_eq!(route.paths[0].hops[0].short_channel_id, 44);
8301 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
8302 pub(crate) mod bench_utils {
8305 use std::time::Duration;
8307 use bitcoin::hashes::Hash;
8308 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
8310 use crate::chain::transaction::OutPoint;
8311 use crate::routing::scoring::ScoreUpdate;
8312 use crate::sign::{EntropySource, KeysManager};
8313 use crate::ln::ChannelId;
8314 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
8315 use crate::ln::features::Bolt11InvoiceFeatures;
8316 use crate::routing::gossip::NetworkGraph;
8317 use crate::util::config::UserConfig;
8318 use crate::util::ser::ReadableArgs;
8319 use crate::util::test_utils::TestLogger;
8321 /// Tries to open a network graph file, or panics with a URL to fetch it.
8322 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
8323 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
8324 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
8325 .or_else(|_| { // Fall back to guessing based on the binary location
8326 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
8327 let mut path = std::env::current_exe().unwrap();
8328 path.pop(); // lightning-...
8330 path.pop(); // debug
8331 path.pop(); // target
8332 path.push("lightning");
8333 path.push("net_graph-2023-01-18.bin");
8336 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
8337 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
8338 let mut path = std::env::current_exe().unwrap();
8339 path.pop(); // bench...
8341 path.pop(); // debug
8342 path.pop(); // target
8343 path.pop(); // bench
8344 path.push("lightning");
8345 path.push("net_graph-2023-01-18.bin");
8348 .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");
8349 #[cfg(require_route_graph_test)]
8350 return Ok(res.unwrap());
8351 #[cfg(not(require_route_graph_test))]
8355 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
8356 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
8359 pub(crate) fn payer_pubkey() -> PublicKey {
8360 let secp_ctx = Secp256k1::new();
8361 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
8365 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
8367 channel_id: ChannelId::new_zero(),
8368 counterparty: ChannelCounterparty {
8369 features: channelmanager::provided_init_features(&UserConfig::default()),
8371 unspendable_punishment_reserve: 0,
8372 forwarding_info: None,
8373 outbound_htlc_minimum_msat: None,
8374 outbound_htlc_maximum_msat: None,
8376 funding_txo: Some(OutPoint {
8377 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
8380 short_channel_id: Some(1),
8381 inbound_scid_alias: None,
8382 outbound_scid_alias: None,
8383 channel_value_satoshis: 10_000_000_000,
8385 balance_msat: 10_000_000_000,
8386 outbound_capacity_msat: 10_000_000_000,
8387 next_outbound_htlc_minimum_msat: 0,
8388 next_outbound_htlc_limit_msat: 10_000_000_000,
8389 inbound_capacity_msat: 0,
8390 unspendable_punishment_reserve: None,
8391 confirmations_required: None,
8392 confirmations: None,
8393 force_close_spend_delay: None,
8395 is_channel_ready: true,
8398 inbound_htlc_minimum_msat: None,
8399 inbound_htlc_maximum_msat: None,
8401 feerate_sat_per_1000_weight: None,
8402 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
8406 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
8407 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
8408 starting_amount: u64, route_count: usize,
8409 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
8410 let payer = payer_pubkey();
8411 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8412 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8414 let nodes = graph.read_only().nodes().clone();
8415 let mut route_endpoints = Vec::new();
8416 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
8417 // with some routes we picked being un-routable.
8418 for _ in 0..route_count * 3 / 2 {
8420 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8421 let src = PublicKey::from_slice(nodes.unordered_keys()
8422 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8423 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8424 let dst = PublicKey::from_slice(nodes.unordered_keys()
8425 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
8426 let params = PaymentParameters::from_node_id(dst, 42)
8427 .with_bolt11_features(features.clone()).unwrap();
8428 let first_hop = first_hop(src);
8429 let amt_msat = starting_amount + seed % 1_000_000;
8430 let route_params = RouteParameters::from_payment_params_and_value(
8431 params.clone(), amt_msat);
8433 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
8434 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
8436 // ...and seed the scorer with success and failure data...
8437 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8438 let mut score_amt = seed % 1_000_000_000;
8440 // Generate fail/success paths for a wider range of potential amounts with
8441 // MPP enabled to give us a chance to apply penalties for more potential
8443 let mpp_features = channelmanager::provided_bolt11_invoice_features(&UserConfig::default());
8444 let params = PaymentParameters::from_node_id(dst, 42)
8445 .with_bolt11_features(mpp_features).unwrap();
8446 let route_params = RouteParameters::from_payment_params_and_value(
8447 params.clone(), score_amt);
8448 let route_res = get_route(&payer, &route_params, &graph.read_only(),
8449 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
8450 &random_seed_bytes);
8451 if let Ok(route) = route_res {
8452 for path in route.paths {
8453 if seed & 0x80 == 0 {
8454 scorer.payment_path_successful(&path, Duration::ZERO);
8456 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
8457 scorer.payment_path_failed(&path, short_channel_id, Duration::ZERO);
8459 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
8463 // If we couldn't find a path with a higer amount, reduce and try again.
8467 route_endpoints.push((first_hop, params, amt_msat));
8473 // Because we've changed channel scores, it's possible we'll take different routes to the
8474 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
8475 // requires a too-high CLTV delta.
8476 route_endpoints.retain(|(first_hop, params, amt_msat)| {
8477 let route_params = RouteParameters::from_payment_params_and_value(
8478 params.clone(), *amt_msat);
8479 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8480 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
8482 route_endpoints.truncate(route_count);
8483 assert_eq!(route_endpoints.len(), route_count);
8491 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
8492 use crate::sign::{EntropySource, KeysManager};
8493 use crate::ln::channelmanager;
8494 use crate::ln::features::Bolt11InvoiceFeatures;
8495 use crate::routing::gossip::NetworkGraph;
8496 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
8497 use crate::util::config::UserConfig;
8498 use crate::util::logger::{Logger, Record};
8499 use crate::util::test_utils::TestLogger;
8501 use criterion::Criterion;
8503 struct DummyLogger {}
8504 impl Logger for DummyLogger {
8505 fn log(&self, _record: Record) {}
8508 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8509 let logger = TestLogger::new();
8510 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8511 let scorer = FixedPenaltyScorer::with_penalty(0);
8512 generate_routes(bench, &network_graph, scorer, &Default::default(),
8513 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
8516 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
8517 let logger = TestLogger::new();
8518 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8519 let scorer = FixedPenaltyScorer::with_penalty(0);
8520 generate_routes(bench, &network_graph, scorer, &Default::default(),
8521 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8522 "generate_mpp_routes_with_zero_penalty_scorer");
8525 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8526 let logger = TestLogger::new();
8527 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8528 let params = ProbabilisticScoringFeeParameters::default();
8529 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8530 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
8531 "generate_routes_with_probabilistic_scorer");
8534 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8535 let logger = TestLogger::new();
8536 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8537 let params = ProbabilisticScoringFeeParameters::default();
8538 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8539 generate_routes(bench, &network_graph, scorer, ¶ms,
8540 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8541 "generate_mpp_routes_with_probabilistic_scorer");
8544 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
8545 let logger = TestLogger::new();
8546 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8547 let params = ProbabilisticScoringFeeParameters::default();
8548 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8549 generate_routes(bench, &network_graph, scorer, ¶ms,
8550 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8551 "generate_large_mpp_routes_with_probabilistic_scorer");
8554 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8555 let logger = TestLogger::new();
8556 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8557 let mut params = ProbabilisticScoringFeeParameters::default();
8558 params.linear_success_probability = false;
8559 let scorer = ProbabilisticScorer::new(
8560 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8561 generate_routes(bench, &network_graph, scorer, ¶ms,
8562 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8563 "generate_routes_with_nonlinear_probabilistic_scorer");
8566 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8567 let logger = TestLogger::new();
8568 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8569 let mut params = ProbabilisticScoringFeeParameters::default();
8570 params.linear_success_probability = false;
8571 let scorer = ProbabilisticScorer::new(
8572 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8573 generate_routes(bench, &network_graph, scorer, ¶ms,
8574 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 0,
8575 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
8578 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
8579 let logger = TestLogger::new();
8580 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
8581 let mut params = ProbabilisticScoringFeeParameters::default();
8582 params.linear_success_probability = false;
8583 let scorer = ProbabilisticScorer::new(
8584 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
8585 generate_routes(bench, &network_graph, scorer, ¶ms,
8586 channelmanager::provided_bolt11_invoice_features(&UserConfig::default()), 100_000_000,
8587 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
8590 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
8591 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
8592 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
8593 bench_name: &'static str,
8595 let payer = bench_utils::payer_pubkey();
8596 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
8597 let random_seed_bytes = keys_manager.get_secure_random_bytes();
8599 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
8600 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
8602 // ...then benchmark finding paths between the nodes we learned.
8604 bench.bench_function(bench_name, |b| b.iter(|| {
8605 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8606 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8607 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8608 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());