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).into_inner();
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>;
93 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
95 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
96 /// and [`RouteParameters::final_value_msat`], respectively.
98 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
100 fn find_route_with_id(
101 &self, payer: &PublicKey, route_params: &RouteParameters,
102 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
103 _payment_hash: PaymentHash, _payment_id: PaymentId
104 ) -> Result<Route, LightningError> {
105 self.find_route(payer, route_params, first_hops, inflight_htlcs)
109 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
111 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
114 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
115 pub struct ScorerAccountingForInFlightHtlcs<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> {
117 // Maps a channel's short channel id and its direction to the liquidity used up.
118 inflight_htlcs: &'a InFlightHtlcs,
120 impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
121 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
122 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
123 ScorerAccountingForInFlightHtlcs {
131 impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> Writeable for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
132 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
135 impl<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
136 type ScoreParams = Sc::ScoreParams;
137 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
138 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
139 source, target, short_channel_id
141 let usage = ChannelUsage {
142 inflight_htlc_msat: usage.inflight_htlc_msat + used_liquidity,
146 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
148 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
153 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
154 /// in-use channel liquidity.
156 pub struct InFlightHtlcs(
157 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
158 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
159 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
161 HashMap<(u64, bool), u64>
165 /// Constructs an empty `InFlightHtlcs`.
166 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
168 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
169 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
170 if path.hops.is_empty() { return };
172 let mut cumulative_msat = 0;
173 if let Some(tail) = &path.blinded_tail {
174 cumulative_msat += tail.final_value_msat;
177 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
178 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
179 // the router excludes the payer node. In the following lines, the payer's information is
180 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
181 // in our sliding window of two.
182 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
183 .map(|hop| hop.pubkey)
184 .chain(core::iter::once(payer_node_id));
186 // Taking the reversed vector from above, we zip it with just the reversed hops list to
187 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
188 // the total amount sent.
189 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
190 cumulative_msat += next_hop.fee_msat;
192 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
193 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
194 .or_insert(cumulative_msat);
198 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
200 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
202 .entry((channel_scid, source < target))
203 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
204 .or_insert(used_msat);
207 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
209 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
210 self.0.get(&(channel_scid, source < target)).map(|v| *v)
214 impl Writeable for InFlightHtlcs {
215 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
218 impl Readable for InFlightHtlcs {
219 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
220 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
221 Ok(Self(infight_map))
225 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
226 /// that leads to it.
227 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
228 pub struct RouteHop {
229 /// The node_id of the node at this hop.
230 pub pubkey: PublicKey,
231 /// The node_announcement features of the node at this hop. For the last hop, these may be
232 /// amended to match the features present in the invoice this node generated.
233 pub node_features: NodeFeatures,
234 /// The channel that should be used from the previous hop to reach this node.
235 pub short_channel_id: u64,
236 /// The channel_announcement features of the channel that should be used from the previous hop
237 /// to reach this node.
238 pub channel_features: ChannelFeatures,
239 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
240 /// If this is the last hop in [`Path::hops`]:
241 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
242 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
244 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
246 /// The CLTV delta added for this hop.
247 /// If this is the last hop in [`Path::hops`]:
248 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
249 /// * otherwise, this is the CLTV delta expected at the destination
251 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
252 pub cltv_expiry_delta: u32,
255 impl_writeable_tlv_based!(RouteHop, {
256 (0, pubkey, required),
257 (2, node_features, required),
258 (4, short_channel_id, required),
259 (6, channel_features, required),
260 (8, fee_msat, required),
261 (10, cltv_expiry_delta, required),
264 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
265 /// their [`Bolt12Invoice`].
267 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
268 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
269 pub struct BlindedTail {
270 /// The hops of the [`BlindedPath`] provided by the recipient.
272 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
273 pub hops: Vec<BlindedHop>,
274 /// The blinding point of the [`BlindedPath`] provided by the recipient.
276 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
277 pub blinding_point: PublicKey,
278 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
279 /// inferring the destination. May be 0.
280 pub excess_final_cltv_expiry_delta: u32,
281 /// The total amount paid on this [`Path`], excluding the fees.
282 pub final_value_msat: u64,
285 impl_writeable_tlv_based!(BlindedTail, {
286 (0, hops, required_vec),
287 (2, blinding_point, required),
288 (4, excess_final_cltv_expiry_delta, required),
289 (6, final_value_msat, required),
292 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
293 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
294 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
296 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
297 pub hops: Vec<RouteHop>,
298 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
299 pub blinded_tail: Option<BlindedTail>,
303 /// Gets the fees for a given path, excluding any excess paid to the recipient.
304 pub fn fee_msat(&self) -> u64 {
305 match &self.blinded_tail {
306 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
308 // Do not count last hop of each path since that's the full value of the payment
309 self.hops.split_last().map_or(0,
310 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
315 /// Gets the total amount paid on this [`Path`], excluding the fees.
316 pub fn final_value_msat(&self) -> u64 {
317 match &self.blinded_tail {
318 Some(blinded_tail) => blinded_tail.final_value_msat,
319 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
323 /// Gets the final hop's CLTV expiry delta.
324 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
325 match &self.blinded_tail {
327 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
332 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
333 /// it can take multiple paths. Each path is composed of one or more hops through the network.
334 #[derive(Clone, Hash, PartialEq, Eq)]
336 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
337 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
339 pub paths: Vec<Path>,
340 /// The `route_params` parameter passed to [`find_route`].
342 /// This is used by `ChannelManager` to track information which may be required for retries.
344 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
345 pub route_params: Option<RouteParameters>,
349 /// Returns the total amount of fees paid on this [`Route`].
351 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
352 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
353 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
355 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
356 pub fn get_total_fees(&self) -> u64 {
357 let overpaid_value_msat = self.route_params.as_ref()
358 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
359 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
362 /// Returns the total amount paid on this [`Route`], excluding the fees.
364 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
365 /// we had to reach the [`htlc_minimum_msat`] limits.
367 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
368 pub fn get_total_amount(&self) -> u64 {
369 self.paths.iter().map(|path| path.final_value_msat()).sum()
373 const SERIALIZATION_VERSION: u8 = 1;
374 const MIN_SERIALIZATION_VERSION: u8 = 1;
376 impl Writeable for Route {
377 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
378 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
379 (self.paths.len() as u64).write(writer)?;
380 let mut blinded_tails = Vec::new();
381 for path in self.paths.iter() {
382 (path.hops.len() as u8).write(writer)?;
383 for (idx, hop) in path.hops.iter().enumerate() {
385 if let Some(blinded_tail) = &path.blinded_tail {
386 if blinded_tails.is_empty() {
387 blinded_tails = Vec::with_capacity(path.hops.len());
389 blinded_tails.push(None);
392 blinded_tails.push(Some(blinded_tail));
393 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
396 write_tlv_fields!(writer, {
397 // For compatibility with LDK versions prior to 0.0.117, we take the individual
398 // RouteParameters' fields and reconstruct them on read.
399 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
400 (2, blinded_tails, optional_vec),
401 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
407 impl Readable for Route {
408 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
409 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
410 let path_count: u64 = Readable::read(reader)?;
411 if path_count == 0 { return Err(DecodeError::InvalidValue); }
412 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
413 let mut min_final_cltv_expiry_delta = u32::max_value();
414 for _ in 0..path_count {
415 let hop_count: u8 = Readable::read(reader)?;
416 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
417 for _ in 0..hop_count {
418 hops.push(Readable::read(reader)?);
420 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
421 min_final_cltv_expiry_delta =
422 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
423 paths.push(Path { hops, blinded_tail: None });
425 _init_and_read_len_prefixed_tlv_fields!(reader, {
426 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
427 (2, blinded_tails, optional_vec),
428 (3, final_value_msat, option),
430 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
431 if blinded_tails.len() != 0 {
432 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
433 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
434 path.blinded_tail = blinded_tail_opt;
438 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
439 let route_params = match (payment_params, final_value_msat) {
440 (Some(payment_params), Some(final_value_msat)) => {
441 Some(RouteParameters { payment_params, final_value_msat })
446 Ok(Route { paths, route_params })
450 /// Parameters needed to find a [`Route`].
452 /// Passed to [`find_route`] and [`build_route_from_hops`].
453 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
454 pub struct RouteParameters {
455 /// The parameters of the failed payment path.
456 pub payment_params: PaymentParameters,
458 /// The amount in msats sent on the failed payment path.
459 pub final_value_msat: u64,
462 impl RouteParameters {
463 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
464 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
465 Self { payment_params, final_value_msat }
469 impl Writeable for RouteParameters {
470 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
471 write_tlv_fields!(writer, {
472 (0, self.payment_params, required),
473 (2, self.final_value_msat, required),
474 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
475 // `RouteParameters` directly. For compatibility, we write it here.
476 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
482 impl Readable for RouteParameters {
483 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
484 _init_and_read_len_prefixed_tlv_fields!(reader, {
485 (0, payment_params, (required: ReadableArgs, 0)),
486 (2, final_value_msat, required),
487 (4, final_cltv_delta, option),
489 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
490 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
491 if final_cltv_expiry_delta == &0 {
492 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
497 final_value_msat: final_value_msat.0.unwrap(),
502 /// Maximum total CTLV difference we allow for a full payment path.
503 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
505 /// Maximum number of paths we allow an (MPP) payment to have.
506 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
507 // limits, but for now more than 10 paths likely carries too much one-path failure.
508 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
510 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
512 // The median hop CLTV expiry delta currently seen in the network.
513 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
515 // During routing, we only consider paths shorter than our maximum length estimate.
516 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
517 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
518 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
520 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
521 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
522 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
523 // (payment_secret and total_msat) = 93 bytes for the final hop.
524 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
525 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
526 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
528 /// Information used to route a payment.
529 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
530 pub struct PaymentParameters {
531 /// Information about the payee, such as their features and route hints for their channels.
534 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
535 pub expiry_time: Option<u64>,
537 /// The maximum total CLTV delta we accept for the route.
538 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
539 pub max_total_cltv_expiry_delta: u32,
541 /// The maximum number of paths that may be used by (MPP) payments.
542 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
543 pub max_path_count: u8,
545 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
546 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
547 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
548 /// increasing failure probability for those paths.
550 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
551 /// restriction have been found. While paths which meet this criteria will be searched for, it
552 /// is ultimately up to the scorer to select them over other paths.
554 /// A value of 0 will allow payments up to and including a channel's total announced usable
555 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
558 pub max_channel_saturation_power_of_half: u8,
560 /// A list of SCIDs which this payment was previously attempted over and which caused the
561 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
563 pub previously_failed_channels: Vec<u64>,
566 impl Writeable for PaymentParameters {
567 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
568 let mut clear_hints = &vec![];
569 let mut blinded_hints = &vec![];
571 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
572 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
574 write_tlv_fields!(writer, {
575 (0, self.payee.node_id(), option),
576 (1, self.max_total_cltv_expiry_delta, required),
577 (2, self.payee.features(), option),
578 (3, self.max_path_count, required),
579 (4, *clear_hints, required_vec),
580 (5, self.max_channel_saturation_power_of_half, required),
581 (6, self.expiry_time, option),
582 (7, self.previously_failed_channels, required_vec),
583 (8, *blinded_hints, optional_vec),
584 (9, self.payee.final_cltv_expiry_delta(), option),
590 impl ReadableArgs<u32> for PaymentParameters {
591 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
592 _init_and_read_len_prefixed_tlv_fields!(reader, {
593 (0, payee_pubkey, option),
594 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
595 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
596 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
597 (4, clear_route_hints, required_vec),
598 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
599 (6, expiry_time, option),
600 (7, previously_failed_channels, optional_vec),
601 (8, blinded_route_hints, optional_vec),
602 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
604 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
605 let payee = if blinded_route_hints.len() != 0 {
606 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
608 route_hints: blinded_route_hints,
609 features: features.and_then(|f: Features| f.bolt12()),
613 route_hints: clear_route_hints,
614 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
615 features: features.and_then(|f| f.bolt11()),
616 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
620 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
621 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
623 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
625 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
631 impl PaymentParameters {
632 /// Creates a payee with the node id of the given `pubkey`.
634 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
636 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
638 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
640 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
641 max_path_count: DEFAULT_MAX_PATH_COUNT,
642 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
643 previously_failed_channels: Vec::new(),
647 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
649 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
652 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
653 /// whether your router will be allowed to find a multi-part route for this payment. If you
654 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
655 /// [`RecipientOnionFields::secret_only`].
657 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
658 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
659 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
660 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
661 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
664 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
665 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
666 /// [`PaymentParameters::expiry_time`].
667 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
668 Self::blinded(invoice.payment_paths().to_vec())
669 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
670 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
673 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
674 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
676 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
678 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
679 max_path_count: DEFAULT_MAX_PATH_COUNT,
680 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
681 previously_failed_channels: Vec::new(),
685 /// Includes the payee's features. Errors if the parameters were not initialized with
686 /// [`PaymentParameters::from_bolt12_invoice`].
688 /// This is not exported to bindings users since bindings don't support move semantics
689 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
691 Payee::Clear { .. } => Err(()),
692 Payee::Blinded { route_hints, .. } =>
693 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
697 /// Includes the payee's features. Errors if the parameters were initialized with
698 /// [`PaymentParameters::from_bolt12_invoice`].
700 /// This is not exported to bindings users since bindings don't support move semantics
701 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
703 Payee::Blinded { .. } => Err(()),
704 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
706 payee: Payee::Clear {
707 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
713 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
714 /// [`PaymentParameters::from_bolt12_invoice`].
716 /// This is not exported to bindings users since bindings don't support move semantics
717 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
719 Payee::Blinded { .. } => Err(()),
720 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
722 payee: Payee::Clear {
723 route_hints, node_id, features, final_cltv_expiry_delta,
729 /// Includes a payment expiration in seconds relative to the UNIX epoch.
731 /// This is not exported to bindings users since bindings don't support move semantics
732 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
733 Self { expiry_time: Some(expiry_time), ..self }
736 /// Includes a limit for the total CLTV expiry delta which is considered during routing
738 /// This is not exported to bindings users since bindings don't support move semantics
739 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
740 Self { max_total_cltv_expiry_delta, ..self }
743 /// Includes a limit for the maximum number of payment paths that may be used.
745 /// This is not exported to bindings users since bindings don't support move semantics
746 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
747 Self { max_path_count, ..self }
750 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
751 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
753 /// This is not exported to bindings users since bindings don't support move semantics
754 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
755 Self { max_channel_saturation_power_of_half, ..self }
759 /// The recipient of a payment, differing based on whether they've hidden their identity with route
761 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
763 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
764 /// will be included in the final [`Route`].
766 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
768 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
769 /// Features supported by the payee.
771 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
773 features: Option<Bolt12InvoiceFeatures>,
775 /// The recipient included these route hints in their BOLT11 invoice.
777 /// The node id of the payee.
779 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
780 route_hints: Vec<RouteHint>,
781 /// Features supported by the payee.
783 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
784 /// does not contain any features.
786 /// [`for_keysend`]: PaymentParameters::for_keysend
787 features: Option<Bolt11InvoiceFeatures>,
788 /// The minimum CLTV delta at the end of the route. This value must not be zero.
789 final_cltv_expiry_delta: u32,
794 fn node_id(&self) -> Option<PublicKey> {
796 Self::Clear { node_id, .. } => Some(*node_id),
800 fn node_features(&self) -> Option<NodeFeatures> {
802 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
803 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
806 fn supports_basic_mpp(&self) -> bool {
808 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
809 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
812 fn features(&self) -> Option<FeaturesRef> {
814 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
815 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
818 fn final_cltv_expiry_delta(&self) -> Option<u32> {
820 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
824 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
826 Self::Blinded { route_hints, .. } => &route_hints[..],
827 Self::Clear { .. } => &[]
831 fn unblinded_route_hints(&self) -> &[RouteHint] {
833 Self::Blinded { .. } => &[],
834 Self::Clear { route_hints, .. } => &route_hints[..]
839 enum FeaturesRef<'a> {
840 Bolt11(&'a Bolt11InvoiceFeatures),
841 Bolt12(&'a Bolt12InvoiceFeatures),
844 Bolt11(Bolt11InvoiceFeatures),
845 Bolt12(Bolt12InvoiceFeatures),
849 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
851 Self::Bolt12(f) => Some(f),
855 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
857 Self::Bolt11(f) => Some(f),
863 impl<'a> Writeable for FeaturesRef<'a> {
864 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
866 Self::Bolt11(f) => Ok(f.write(w)?),
867 Self::Bolt12(f) => Ok(f.write(w)?),
872 impl ReadableArgs<bool> for Features {
873 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
874 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
875 Ok(Self::Bolt12(Readable::read(reader)?))
879 /// A list of hops along a payment path terminating with a channel to the recipient.
880 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
881 pub struct RouteHint(pub Vec<RouteHintHop>);
883 impl Writeable for RouteHint {
884 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
885 (self.0.len() as u64).write(writer)?;
886 for hop in self.0.iter() {
893 impl Readable for RouteHint {
894 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
895 let hop_count: u64 = Readable::read(reader)?;
896 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
897 for _ in 0..hop_count {
898 hops.push(Readable::read(reader)?);
904 /// A channel descriptor for a hop along a payment path.
905 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
906 pub struct RouteHintHop {
907 /// The node_id of the non-target end of the route
908 pub src_node_id: PublicKey,
909 /// The short_channel_id of this channel
910 pub short_channel_id: u64,
911 /// The fees which must be paid to use this channel
912 pub fees: RoutingFees,
913 /// The difference in CLTV values between this node and the next node.
914 pub cltv_expiry_delta: u16,
915 /// The minimum value, in msat, which must be relayed to the next hop.
916 pub htlc_minimum_msat: Option<u64>,
917 /// The maximum value in msat available for routing with a single HTLC.
918 pub htlc_maximum_msat: Option<u64>,
921 impl_writeable_tlv_based!(RouteHintHop, {
922 (0, src_node_id, required),
923 (1, htlc_minimum_msat, option),
924 (2, short_channel_id, required),
925 (3, htlc_maximum_msat, option),
927 (6, cltv_expiry_delta, required),
930 #[derive(Eq, PartialEq)]
931 struct RouteGraphNode {
933 lowest_fee_to_node: u64,
934 total_cltv_delta: u32,
935 // The maximum value a yet-to-be-constructed payment path might flow through this node.
936 // This value is upper-bounded by us by:
937 // - how much is needed for a path being constructed
938 // - how much value can channels following this node (up to the destination) can contribute,
939 // considering their capacity and fees
940 value_contribution_msat: u64,
941 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
942 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
943 path_htlc_minimum_msat: u64,
944 /// All penalties incurred from this hop on the way to the destination, as calculated using
946 path_penalty_msat: u64,
947 /// The number of hops walked up to this node.
948 path_length_to_node: u8,
951 impl cmp::Ord for RouteGraphNode {
952 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
953 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
954 .saturating_add(other.path_penalty_msat);
955 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
956 .saturating_add(self.path_penalty_msat);
957 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
961 impl cmp::PartialOrd for RouteGraphNode {
962 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
963 Some(self.cmp(other))
967 /// A wrapper around the various hop representations.
969 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
970 #[derive(Clone, Debug)]
971 enum CandidateRouteHop<'a> {
972 /// A hop from the payer, where the outbound liquidity is known.
974 details: &'a ChannelDetails,
976 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
978 info: DirectedChannelInfo<'a>,
979 short_channel_id: u64,
981 /// A hop to the payee found in the BOLT 11 payment invoice, though not necessarily a direct
984 hint: &'a RouteHintHop,
986 /// The payee's identity is concealed behind blinded paths provided in a BOLT 12 invoice.
988 hint: &'a (BlindedPayInfo, BlindedPath),
991 /// Similar to [`Self::Blinded`], but the path here has 1 blinded hop. `BlindedPayInfo` provided
992 /// for 1-hop blinded paths is ignored because it is meant to apply to the hops *between* the
993 /// introduction node and the destination. Useful for tracking that we need to include a blinded
994 /// path at the end of our [`Route`].
996 hint: &'a (BlindedPayInfo, BlindedPath),
1001 impl<'a> CandidateRouteHop<'a> {
1002 fn short_channel_id(&self) -> Option<u64> {
1004 CandidateRouteHop::FirstHop { details } => Some(details.get_outbound_payment_scid().unwrap()),
1005 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1006 CandidateRouteHop::PrivateHop { hint } => Some(hint.short_channel_id),
1007 CandidateRouteHop::Blinded { .. } => None,
1008 CandidateRouteHop::OneHopBlinded { .. } => None,
1012 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1013 fn features(&self) -> ChannelFeatures {
1015 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
1016 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1017 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1018 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1019 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1023 fn cltv_expiry_delta(&self) -> u32 {
1025 CandidateRouteHop::FirstHop { .. } => 0,
1026 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1027 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
1028 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1029 CandidateRouteHop::OneHopBlinded { .. } => 0,
1033 fn htlc_minimum_msat(&self) -> u64 {
1035 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat,
1036 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1037 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
1038 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1039 CandidateRouteHop::OneHopBlinded { .. } => 0,
1043 fn fees(&self) -> RoutingFees {
1045 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1046 base_msat: 0, proportional_millionths: 0,
1048 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1049 CandidateRouteHop::PrivateHop { hint } => hint.fees,
1050 CandidateRouteHop::Blinded { hint, .. } => {
1052 base_msat: hint.0.fee_base_msat,
1053 proportional_millionths: hint.0.fee_proportional_millionths
1056 CandidateRouteHop::OneHopBlinded { .. } =>
1057 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1061 fn effective_capacity(&self) -> EffectiveCapacity {
1063 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
1064 liquidity_msat: details.next_outbound_htlc_limit_msat,
1066 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1067 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }} =>
1068 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1069 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }} =>
1070 EffectiveCapacity::Infinite,
1071 CandidateRouteHop::Blinded { hint, .. } =>
1072 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1073 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1077 fn id(&self, channel_direction: bool /* src_node_id < target_node_id */) -> CandidateHopId {
1079 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1080 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1081 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), channel_direction)),
1084 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1086 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1094 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1095 enum CandidateHopId {
1096 /// Contains (scid, src_node_id < target_node_id)
1098 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1103 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1104 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1106 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1107 EffectiveCapacity::Infinite => u64::max_value(),
1108 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1109 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1110 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1111 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1112 // expected to have been generated from up-to-date capacity information.
1113 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1114 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1115 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1119 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1120 -> bool where I1::Item: PartialEq<I2::Item> {
1122 let a = iter_a.next();
1123 let b = iter_b.next();
1124 if a.is_none() && b.is_none() { return true; }
1125 if a.is_none() || b.is_none() { return false; }
1126 if a.unwrap().ne(&b.unwrap()) { return false; }
1130 /// It's useful to keep track of the hops associated with the fees required to use them,
1131 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1132 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1133 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1135 struct PathBuildingHop<'a> {
1136 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
1137 // is a larger refactor and will require careful performance analysis.
1139 candidate: CandidateRouteHop<'a>,
1142 /// All the fees paid *after* this channel on the way to the destination
1143 next_hops_fee_msat: u64,
1144 /// Fee paid for the use of the current channel (see candidate.fees()).
1145 /// The value will be actually deducted from the counterparty balance on the previous link.
1146 hop_use_fee_msat: u64,
1147 /// Used to compare channels when choosing the for routing.
1148 /// Includes paying for the use of a hop and the following hops, as well as
1149 /// an estimated cost of reaching this hop.
1150 /// Might get stale when fees are recomputed. Primarily for internal use.
1151 total_fee_msat: u64,
1152 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1153 /// walk and may be invalid thereafter.
1154 path_htlc_minimum_msat: u64,
1155 /// All penalties incurred from this channel on the way to the destination, as calculated using
1156 /// channel scoring.
1157 path_penalty_msat: u64,
1158 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1159 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1160 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1161 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1162 /// avoid processing them again.
1163 was_processed: bool,
1164 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1165 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1166 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1167 // value_contribution_msat, which requires tracking it here. See comments below where it is
1168 // used for more info.
1169 value_contribution_msat: u64,
1172 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1173 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1174 let mut debug_struct = f.debug_struct("PathBuildingHop");
1176 .field("node_id", &self.node_id)
1177 .field("short_channel_id", &self.candidate.short_channel_id())
1178 .field("total_fee_msat", &self.total_fee_msat)
1179 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1180 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1181 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat - (&self.next_hops_fee_msat + &self.hop_use_fee_msat)))
1182 .field("path_penalty_msat", &self.path_penalty_msat)
1183 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1184 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1185 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1186 let debug_struct = debug_struct
1187 .field("value_contribution_msat", &self.value_contribution_msat);
1188 debug_struct.finish()
1192 // Instantiated with a list of hops with correct data in them collected during path finding,
1193 // an instance of this struct should be further modified only via given methods.
1195 struct PaymentPath<'a> {
1196 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1199 impl<'a> PaymentPath<'a> {
1200 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1201 fn get_value_msat(&self) -> u64 {
1202 self.hops.last().unwrap().0.fee_msat
1205 fn get_path_penalty_msat(&self) -> u64 {
1206 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1209 fn get_total_fee_paid_msat(&self) -> u64 {
1210 if self.hops.len() < 1 {
1214 // Can't use next_hops_fee_msat because it gets outdated.
1215 for (i, (hop, _)) in self.hops.iter().enumerate() {
1216 if i != self.hops.len() - 1 {
1217 result += hop.fee_msat;
1223 fn get_cost_msat(&self) -> u64 {
1224 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1227 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1228 // to change fees may result in an inconsistency.
1230 // Sometimes we call this function right after constructing a path which is inconsistent in
1231 // that it the value being transferred has decreased while we were doing path finding, leading
1232 // to the fees being paid not lining up with the actual limits.
1234 // Note that this function is not aware of the available_liquidity limit, and thus does not
1235 // support increasing the value being transferred beyond what was selected during the initial
1237 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
1238 let mut total_fee_paid_msat = 0 as u64;
1239 for i in (0..self.hops.len()).rev() {
1240 let last_hop = i == self.hops.len() - 1;
1242 // For non-last-hop, this value will represent the fees paid on the current hop. It
1243 // will consist of the fees for the use of the next hop, and extra fees to match
1244 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1245 let mut cur_hop_fees_msat = 0;
1247 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1250 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1251 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1252 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1253 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1254 // set it too high just to maliciously take more fees by exploiting this
1255 // match htlc_minimum_msat logic.
1256 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1257 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1258 // Note that there is a risk that *previous hops* (those closer to us, as we go
1259 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1261 // This might make us end up with a broken route, although this should be super-rare
1262 // in practice, both because of how healthy channels look like, and how we pick
1263 // channels in add_entry.
1264 // Also, this can't be exploited more heavily than *announce a free path and fail
1266 cur_hop_transferred_amount_msat += extra_fees_msat;
1267 total_fee_paid_msat += extra_fees_msat;
1268 cur_hop_fees_msat += extra_fees_msat;
1272 // Final hop is a special case: it usually has just value_msat (by design), but also
1273 // it still could overpay for the htlc_minimum_msat.
1274 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1276 // Propagate updated fees for the use of the channels to one hop back, where they
1277 // will be actually paid (fee_msat). The last hop is handled above separately.
1278 cur_hop.fee_msat = cur_hop_fees_msat;
1281 // Fee for the use of the current hop which will be deducted on the previous hop.
1282 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1283 // this channel is free for us.
1285 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1286 cur_hop.hop_use_fee_msat = new_fee;
1287 total_fee_paid_msat += new_fee;
1289 // It should not be possible because this function is called only to reduce the
1290 // value. In that case, compute_fee was already called with the same fees for
1291 // larger amount and there was no overflow.
1300 /// Calculate the fees required to route the given amount over a channel with the given fees.
1301 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1302 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1303 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1307 /// Calculate the fees required to route the given amount over a channel with the given fees,
1308 /// saturating to [`u64::max_value`].
1309 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1310 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1311 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1312 .saturating_add(channel_fees.base_msat as u64)
1315 /// The default `features` we assume for a node in a route, when no `features` are known about that
1318 /// Default features are:
1319 /// * variable_length_onion_optional
1320 fn default_node_features() -> NodeFeatures {
1321 let mut features = NodeFeatures::empty();
1322 features.set_variable_length_onion_optional();
1326 struct LoggedPayeePubkey(Option<PublicKey>);
1327 impl fmt::Display for LoggedPayeePubkey {
1328 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1331 "payee node id ".fmt(f)?;
1335 "blinded payee".fmt(f)
1341 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1342 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1343 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1345 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1346 "blinded route hint with introduction node id ".fmt(f)?;
1347 hint.1.introduction_node_id.fmt(f)?;
1348 " and blinding point ".fmt(f)?;
1349 hint.1.blinding_point.fmt(f)
1351 CandidateRouteHop::FirstHop { .. } => {
1352 "first hop with SCID ".fmt(f)?;
1353 self.0.short_channel_id().unwrap().fmt(f)
1355 CandidateRouteHop::PrivateHop { .. } => {
1356 "route hint with SCID ".fmt(f)?;
1357 self.0.short_channel_id().unwrap().fmt(f)
1361 self.0.short_channel_id().unwrap().fmt(f)
1368 fn sort_first_hop_channels(
1369 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1370 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1372 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1373 // most like to use.
1375 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1376 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1379 // Second, because simply always sorting in descending order would always use our largest
1380 // available outbound capacity, needlessly fragmenting our available channel capacities,
1381 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1382 // which have enough, but not too much, capacity for the payment.
1384 // Available outbound balances factor in liquidity already reserved for previously found paths.
1385 channels.sort_unstable_by(|chan_a, chan_b| {
1386 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1387 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1388 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1389 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1390 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1391 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1392 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1393 // Sort in descending order
1394 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1396 // Sort in ascending order
1397 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1402 /// Finds a route from us (payer) to the given target node (payee).
1404 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1405 /// in the given [`RouteParameters::payment_params`].
1406 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1408 /// Private routing paths between a public node and the target may be included in the `payee` field
1409 /// of [`RouteParameters::payment_params`].
1411 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1412 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1413 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1415 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1416 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1417 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1421 /// Panics if first_hops contains channels without `short_channel_id`s;
1422 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1424 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1425 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1426 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1427 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1428 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1429 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1430 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1431 ) -> Result<Route, LightningError>
1432 where L::Target: Logger, GL::Target: Logger {
1433 let graph_lock = network_graph.read_only();
1434 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1435 scorer, score_params, random_seed_bytes)?;
1436 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1440 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1441 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1442 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1443 _random_seed_bytes: &[u8; 32]
1444 ) -> Result<Route, LightningError>
1445 where L::Target: Logger {
1447 let payment_params = &route_params.payment_params;
1448 let final_value_msat = route_params.final_value_msat;
1449 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1450 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1451 // so use a dummy id for this in the blinded case.
1452 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1453 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1454 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1455 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1456 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1458 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1459 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1462 if final_value_msat > MAX_VALUE_MSAT {
1463 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1466 if final_value_msat == 0 {
1467 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1470 match &payment_params.payee {
1471 Payee::Clear { route_hints, node_id, .. } => {
1472 for route in route_hints.iter() {
1473 for hop in &route.0 {
1474 if hop.src_node_id == *node_id {
1475 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1480 Payee::Blinded { route_hints, .. } => {
1481 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1482 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});
1484 for (_, blinded_path) in route_hints.iter() {
1485 if blinded_path.blinded_hops.len() == 0 {
1486 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1487 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1488 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1489 } else if blinded_path.blinded_hops.len() == 1 &&
1490 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1491 && p.introduction_node_id != blinded_path.introduction_node_id)
1493 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1498 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1499 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1500 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});
1503 // The general routing idea is the following:
1504 // 1. Fill first/last hops communicated by the caller.
1505 // 2. Attempt to construct a path from payer to payee for transferring
1506 // any ~sufficient (described later) value.
1507 // If succeed, remember which channels were used and how much liquidity they have available,
1508 // so that future paths don't rely on the same liquidity.
1509 // 3. Proceed to the next step if:
1510 // - we hit the recommended target value;
1511 // - OR if we could not construct a new path. Any next attempt will fail too.
1512 // Otherwise, repeat step 2.
1513 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1514 // (not recommended value).
1515 // 5. If yes, proceed. If not, fail routing.
1516 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1517 // transferred up to the transfer target value.
1518 // 7. Reduce the value of the last path until we are sending only the target value.
1519 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1520 // them so that we're not sending two HTLCs along the same path.
1522 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1523 // distance from the payee
1525 // We are not a faithful Dijkstra's implementation because we can change values which impact
1526 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1527 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1528 // the value we are currently attempting to send over a path, we simply reduce the value being
1529 // sent along the path for any hops after that channel. This may imply that later fees (which
1530 // we've already tabulated) are lower because a smaller value is passing through the channels
1531 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1532 // channels which were selected earlier (and which may still be used for other paths without a
1533 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1536 // One potentially problematic case for this algorithm would be if there are many
1537 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1538 // graph walking), we may never find a path which is not liquidity-limited and has lower
1539 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1540 // Because we only consider paths with at least 5% of the total value being sent, the damage
1541 // from such a case should be limited, however this could be further reduced in the future by
1542 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1543 // limits for the purposes of fee calculation.
1545 // Alternatively, we could store more detailed path information in the heap (targets, below)
1546 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1547 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1548 // and practically (as we would need to store dynamically-allocated path information in heap
1549 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1550 // results of such an algorithm would likely be biased towards lower-value paths.
1552 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1553 // outside of our current search value, running a path search more times to gather candidate
1554 // paths at different values. While this may be acceptable, further path searches may increase
1555 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1556 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1557 // the same time, remaining generic across different payment values.
1559 let network_channels = network_graph.channels();
1560 let network_nodes = network_graph.nodes();
1562 if payment_params.max_path_count == 0 {
1563 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1566 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1567 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1569 let allow_mpp = if payment_params.max_path_count == 1 {
1571 } else if payment_params.payee.supports_basic_mpp() {
1573 } else if let Some(payee) = payee_node_id_opt {
1574 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1575 |info| info.features.supports_basic_mpp()))
1578 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1579 LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
1580 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1583 // Prepare the data we'll use for payee-to-payer search by
1584 // inserting first hops suggested by the caller as targets.
1585 // Our search will then attempt to reach them while traversing from the payee node.
1586 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1587 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1588 if let Some(hops) = first_hops {
1590 if chan.get_outbound_payment_scid().is_none() {
1591 panic!("first_hops should be filled in with usable channels, not pending ones");
1593 if chan.counterparty.node_id == *our_node_pubkey {
1594 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1597 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1598 .or_insert(Vec::new())
1601 if first_hop_targets.is_empty() {
1602 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1606 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1607 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1608 // adding duplicate entries when we find a better path to a given node.
1609 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1611 // Map from node_id to information about the best current path to that node, including feerate
1613 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1615 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1616 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1617 // htlc_minimum with extra fees while still finding a cheaper path.
1618 let mut hit_minimum_limit;
1620 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1621 // We start with a path_value of the exact amount we want, and if that generates a route we may
1622 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1623 // amount we want in total across paths, selecting the best subset at the end.
1624 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1625 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1626 let mut path_value_msat = final_value_msat;
1628 // Routing Fragmentation Mitigation heuristic:
1630 // Routing fragmentation across many payment paths increases the overall routing
1631 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1632 // Taking too many smaller paths also increases the chance of payment failure.
1633 // Thus to avoid this effect, we require from our collected links to provide
1634 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1635 // This requirement is currently set to be 1/max_path_count of the payment
1636 // value to ensure we only ever return routes that do not violate this limit.
1637 let minimal_value_contribution_msat: u64 = if allow_mpp {
1638 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1643 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1644 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1645 // drop the requirement by setting this to 0.
1646 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1648 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1649 // determine if the channel can be used by additional MPP paths or to inform path finding
1650 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1651 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1653 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1654 HashMap::with_capacity(network_nodes.len());
1656 // Keeping track of how much value we already collected across other paths. Helps to decide
1657 // when we want to stop looking for new paths.
1658 let mut already_collected_value_msat = 0;
1660 for (_, channels) in first_hop_targets.iter_mut() {
1661 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1665 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1666 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1668 // Remember how many candidates we ignored to allow for some logging afterwards.
1669 let mut num_ignored_value_contribution = 0;
1670 let mut num_ignored_path_length_limit = 0;
1671 let mut num_ignored_cltv_delta_limit = 0;
1672 let mut num_ignored_previously_failed = 0;
1674 macro_rules! add_entry {
1675 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1676 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1677 // since that value has to be transferred over this channel.
1678 // Returns whether this channel caused an update to `targets`.
1679 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1680 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1681 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1682 // We "return" whether we updated the path at the end, and how much we can route via
1683 // this channel, via this:
1684 let mut did_add_update_path_to_src_node = None;
1685 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1686 // practice these cases should be caught earlier:
1687 // - for regular channels at channel announcement (TODO)
1688 // - for first and last hops early in get_route
1689 if $src_node_id != $dest_node_id {
1690 let scid_opt = $candidate.short_channel_id();
1691 let effective_capacity = $candidate.effective_capacity();
1692 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1694 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1695 // It may be misleading because we might later choose to reduce the value transferred
1696 // over these channels, and the channel which was insufficient might become sufficient.
1697 // Worst case: we drop a good channel here because it can't cover the high following
1698 // fees caused by one expensive channel, but then this channel could have been used
1699 // if the amount being transferred over this path is lower.
1700 // We do this for now, but this is a subject for removal.
1701 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1702 let used_liquidity_msat = used_liquidities
1703 .get(&$candidate.id($src_node_id < $dest_node_id))
1704 .map_or(0, |used_liquidity_msat| {
1705 available_value_contribution_msat = available_value_contribution_msat
1706 .saturating_sub(*used_liquidity_msat);
1707 *used_liquidity_msat
1710 // Verify the liquidity offered by this channel complies to the minimal contribution.
1711 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1712 // Do not consider candidate hops that would exceed the maximum path length.
1713 let path_length_to_node = $next_hops_path_length + 1;
1714 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1716 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1717 // In order to already account for some of the privacy enhancing random CLTV
1718 // expiry delta offset we add on top later, we subtract a rough estimate
1719 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1720 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1721 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1722 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1723 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1724 .saturating_add($candidate.cltv_expiry_delta());
1725 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1727 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1728 // Includes paying fees for the use of the following channels.
1729 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1730 Some(result) => result,
1731 // Can't overflow due to how the values were computed right above.
1732 None => unreachable!(),
1734 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1735 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1736 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1738 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1739 let may_overpay_to_meet_path_minimum_msat =
1740 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1741 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1742 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1743 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1745 let payment_failed_on_this_channel = scid_opt.map_or(false,
1746 |scid| payment_params.previously_failed_channels.contains(&scid));
1748 let should_log_candidate = match $candidate {
1749 CandidateRouteHop::FirstHop { .. } => true,
1750 CandidateRouteHop::PrivateHop { .. } => true,
1751 CandidateRouteHop::Blinded { .. } => true,
1755 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1756 // bother considering this channel. If retrying with recommended_value_msat may
1757 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1758 // around again with a higher amount.
1759 if !contributes_sufficient_value {
1760 if should_log_candidate {
1761 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1763 num_ignored_value_contribution += 1;
1764 } else if exceeds_max_path_length {
1765 if should_log_candidate {
1766 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1768 num_ignored_path_length_limit += 1;
1769 } else if exceeds_cltv_delta_limit {
1770 if should_log_candidate {
1771 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1773 num_ignored_cltv_delta_limit += 1;
1774 } else if payment_failed_on_this_channel {
1775 if should_log_candidate {
1776 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1778 num_ignored_previously_failed += 1;
1779 } else if may_overpay_to_meet_path_minimum_msat {
1780 hit_minimum_limit = true;
1781 } else if over_path_minimum_msat {
1782 // Note that low contribution here (limited by available_liquidity_msat)
1783 // might violate htlc_minimum_msat on the hops which are next along the
1784 // payment path (upstream to the payee). To avoid that, we recompute
1785 // path fees knowing the final path contribution after constructing it.
1786 let path_htlc_minimum_msat = cmp::max(
1787 compute_fees_saturating($next_hops_path_htlc_minimum_msat, $candidate.fees())
1788 .saturating_add($next_hops_path_htlc_minimum_msat),
1789 $candidate.htlc_minimum_msat());
1790 let hm_entry = dist.entry($src_node_id);
1791 let old_entry = hm_entry.or_insert_with(|| {
1792 // If there was previously no known way to access the source node
1793 // (recall it goes payee-to-payer) of short_channel_id, first add a
1794 // semi-dummy record just to compute the fees to reach the source node.
1795 // This will affect our decision on selecting short_channel_id
1796 // as a way to reach the $dest_node_id.
1798 node_id: $dest_node_id.clone(),
1799 candidate: $candidate.clone(),
1801 next_hops_fee_msat: u64::max_value(),
1802 hop_use_fee_msat: u64::max_value(),
1803 total_fee_msat: u64::max_value(),
1804 path_htlc_minimum_msat,
1805 path_penalty_msat: u64::max_value(),
1806 was_processed: false,
1807 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1808 value_contribution_msat,
1812 #[allow(unused_mut)] // We only use the mut in cfg(test)
1813 let mut should_process = !old_entry.was_processed;
1814 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1816 // In test/fuzzing builds, we do extra checks to make sure the skipping
1817 // of already-seen nodes only happens in cases we expect (see below).
1818 if !should_process { should_process = true; }
1822 let mut hop_use_fee_msat = 0;
1823 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1825 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1826 // will have the same effective-fee
1827 if $src_node_id != our_node_id {
1828 // Note that `u64::max_value` means we'll always fail the
1829 // `old_entry.total_fee_msat > total_fee_msat` check below
1830 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1831 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1834 let channel_usage = ChannelUsage {
1835 amount_msat: amount_to_transfer_over_msat,
1836 inflight_htlc_msat: used_liquidity_msat,
1839 let channel_penalty_msat = scid_opt.map_or(0,
1840 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1841 channel_usage, score_params));
1842 let path_penalty_msat = $next_hops_path_penalty_msat
1843 .saturating_add(channel_penalty_msat);
1844 let new_graph_node = RouteGraphNode {
1845 node_id: $src_node_id,
1846 lowest_fee_to_node: total_fee_msat,
1847 total_cltv_delta: hop_total_cltv_delta,
1848 value_contribution_msat,
1849 path_htlc_minimum_msat,
1851 path_length_to_node,
1854 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1855 // if this way is cheaper than the already known
1856 // (considering the cost to "reach" this channel from the route destination,
1857 // the cost of using this channel,
1858 // and the cost of routing to the source node of this channel).
1859 // Also, consider that htlc_minimum_msat_difference, because we might end up
1860 // paying it. Consider the following exploit:
1861 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1862 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1863 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1864 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1866 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1867 // but it may require additional tracking - we don't want to double-count
1868 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1869 // can't use something that may decrease on future hops.
1870 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1871 .saturating_add(old_entry.path_penalty_msat);
1872 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1873 .saturating_add(path_penalty_msat);
1875 if !old_entry.was_processed && new_cost < old_cost {
1876 targets.push(new_graph_node);
1877 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1878 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1879 old_entry.total_fee_msat = total_fee_msat;
1880 old_entry.node_id = $dest_node_id.clone();
1881 old_entry.candidate = $candidate.clone();
1882 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1883 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1884 old_entry.path_penalty_msat = path_penalty_msat;
1885 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1887 old_entry.value_contribution_msat = value_contribution_msat;
1889 did_add_update_path_to_src_node = Some(value_contribution_msat);
1890 } else if old_entry.was_processed && new_cost < old_cost {
1891 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1893 // If we're skipping processing a node which was previously
1894 // processed even though we found another path to it with a
1895 // cheaper fee, check that it was because the second path we
1896 // found (which we are processing now) has a lower value
1897 // contribution due to an HTLC minimum limit.
1899 // e.g. take a graph with two paths from node 1 to node 2, one
1900 // through channel A, and one through channel B. Channel A and
1901 // B are both in the to-process heap, with their scores set by
1902 // a higher htlc_minimum than fee.
1903 // Channel A is processed first, and the channels onwards from
1904 // node 1 are added to the to-process heap. Thereafter, we pop
1905 // Channel B off of the heap, note that it has a much more
1906 // restrictive htlc_maximum_msat, and recalculate the fees for
1907 // all of node 1's channels using the new, reduced, amount.
1909 // This would be bogus - we'd be selecting a higher-fee path
1910 // with a lower htlc_maximum_msat instead of the one we'd
1911 // already decided to use.
1912 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1914 value_contribution_msat + path_penalty_msat <
1915 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1923 did_add_update_path_to_src_node
1927 let default_node_features = default_node_features();
1929 // Find ways (channels with destination) to reach a given node and store them
1930 // in the corresponding data structures (routing graph etc).
1931 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1932 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1933 // This data can later be helpful to optimize routing (pay lower fees).
1934 macro_rules! add_entries_to_cheapest_to_target_node {
1935 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1936 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1937 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1938 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1939 let was_processed = elem.was_processed;
1940 elem.was_processed = true;
1943 // Entries are added to dist in add_entry!() when there is a channel from a node.
1944 // Because there are no channels from payee, it will not have a dist entry at this point.
1945 // If we're processing any other node, it is always be the result of a channel from it.
1946 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
1951 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1952 for details in first_channels {
1953 let candidate = CandidateRouteHop::FirstHop { details };
1954 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1955 $next_hops_value_contribution,
1956 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1957 $next_hops_cltv_delta, $next_hops_path_length);
1961 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1964 &default_node_features
1967 if !features.requires_unknown_bits() {
1968 for chan_id in $node.channels.iter() {
1969 let chan = network_channels.get(chan_id).unwrap();
1970 if !chan.features.requires_unknown_bits() {
1971 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1972 if first_hops.is_none() || *source != our_node_id {
1973 if directed_channel.direction().enabled {
1974 let candidate = CandidateRouteHop::PublicHop {
1975 info: directed_channel,
1976 short_channel_id: *chan_id,
1978 add_entry!(candidate, *source, $node_id,
1979 $fee_to_target_msat,
1980 $next_hops_value_contribution,
1981 $next_hops_path_htlc_minimum_msat,
1982 $next_hops_path_penalty_msat,
1983 $next_hops_cltv_delta, $next_hops_path_length);
1994 let mut payment_paths = Vec::<PaymentPath>::new();
1996 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1997 'paths_collection: loop {
1998 // For every new path, start from scratch, except for used_liquidities, which
1999 // helps to avoid reusing previously selected paths in future iterations.
2002 hit_minimum_limit = false;
2004 // If first hop is a private channel and the only way to reach the payee, this is the only
2005 // place where it could be added.
2006 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2007 for details in first_channels {
2008 let candidate = CandidateRouteHop::FirstHop { details };
2009 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
2010 0, 0u64, 0, 0).is_some();
2011 log_trace!(logger, "{} direct route to payee via {}",
2012 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2016 // Add the payee as a target, so that the payee-to-payer
2017 // search algorithm knows what to start with.
2018 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2019 // The payee is not in our network graph, so nothing to add here.
2020 // There is still a chance of reaching them via last_hops though,
2021 // so don't yet fail the payment here.
2022 // If not, targets.pop() will not even let us enter the loop in step 2.
2025 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2030 // If a caller provided us with last hops, add them to routing targets. Since this happens
2031 // earlier than general path finding, they will be somewhat prioritized, although currently
2032 // it matters only if the fees are exactly the same.
2033 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2034 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2035 let have_intro_node_in_graph =
2036 // Only add the hops in this route to our candidate set if either
2037 // we have a direct channel to the first hop or the first hop is
2038 // in the regular network graph.
2039 first_hop_targets.get(&intro_node_id).is_some() ||
2040 network_nodes.get(&intro_node_id).is_some();
2041 if !have_intro_node_in_graph { continue }
2042 let candidate = if hint.1.blinded_hops.len() == 1 {
2043 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2044 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2045 let mut path_contribution_msat = path_value_msat;
2046 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2047 0, path_contribution_msat, 0, 0_u64, 0, 0)
2049 path_contribution_msat = hop_used_msat;
2051 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2052 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2054 for details in first_channels {
2055 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2056 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2060 add_entry!(first_hop_candidate, our_node_id, intro_node_id, blinded_path_fee,
2061 path_contribution_msat, candidate.htlc_minimum_msat(), 0_u64,
2062 candidate.cltv_expiry_delta(),
2063 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2067 for route in payment_params.payee.unblinded_route_hints().iter()
2068 .filter(|route| !route.0.is_empty())
2070 let first_hop_in_route = &(route.0)[0];
2071 let have_hop_src_in_graph =
2072 // Only add the hops in this route to our candidate set if either
2073 // we have a direct channel to the first hop or the first hop is
2074 // in the regular network graph.
2075 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
2076 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
2077 if have_hop_src_in_graph {
2078 // We start building the path from reverse, i.e., from payee
2079 // to the first RouteHintHop in the path.
2080 let hop_iter = route.0.iter().rev();
2081 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2082 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2083 let mut hop_used = true;
2084 let mut aggregate_next_hops_fee_msat: u64 = 0;
2085 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2086 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2087 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2088 let mut aggregate_next_hops_path_length: u8 = 0;
2089 let mut aggregate_path_contribution_msat = path_value_msat;
2091 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2092 let source = NodeId::from_pubkey(&hop.src_node_id);
2093 let target = NodeId::from_pubkey(&prev_hop_id);
2094 let candidate = network_channels
2095 .get(&hop.short_channel_id)
2096 .and_then(|channel| channel.as_directed_to(&target))
2097 .map(|(info, _)| CandidateRouteHop::PublicHop {
2099 short_channel_id: hop.short_channel_id,
2101 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2103 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2104 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2105 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2106 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2108 aggregate_path_contribution_msat = hop_used_msat;
2110 // If this hop was not used then there is no use checking the preceding
2111 // hops in the RouteHint. We can break by just searching for a direct
2112 // channel between last checked hop and first_hop_targets.
2116 let used_liquidity_msat = used_liquidities
2117 .get(&candidate.id(source < target)).copied()
2119 let channel_usage = ChannelUsage {
2120 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2121 inflight_htlc_msat: used_liquidity_msat,
2122 effective_capacity: candidate.effective_capacity(),
2124 let channel_penalty_msat = scorer.channel_penalty_msat(
2125 hop.short_channel_id, &source, &target, channel_usage, score_params
2127 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2128 .saturating_add(channel_penalty_msat);
2130 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2131 .saturating_add(hop.cltv_expiry_delta as u32);
2133 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2136 // Searching for a direct channel between last checked hop and first_hop_targets
2137 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&prev_hop_id)) {
2138 sort_first_hop_channels(first_channels, &used_liquidities,
2139 recommended_value_msat, our_node_pubkey);
2140 for details in first_channels {
2141 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2142 add_entry!(first_hop_candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
2143 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2144 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2145 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2153 // In the next values of the iterator, the aggregate fees already reflects
2154 // the sum of value sent from payer (final_value_msat) and routing fees
2155 // for the last node in the RouteHint. We need to just add the fees to
2156 // route through the current node so that the preceding node (next iteration)
2158 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2159 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2160 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2162 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
2163 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
2164 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
2165 .checked_add(hop_htlc_minimum_msat_inc);
2166 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
2168 if idx == route.0.len() - 1 {
2169 // The last hop in this iterator is the first hop in
2170 // overall RouteHint.
2171 // If this hop connects to a node with which we have a direct channel,
2172 // ignore the network graph and, if the last hop was added, add our
2173 // direct channel to the candidate set.
2175 // Note that we *must* check if the last hop was added as `add_entry`
2176 // always assumes that the third argument is a node to which we have a
2178 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2179 sort_first_hop_channels(first_channels, &used_liquidities,
2180 recommended_value_msat, our_node_pubkey);
2181 for details in first_channels {
2182 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2183 add_entry!(first_hop_candidate, our_node_id,
2184 NodeId::from_pubkey(&hop.src_node_id),
2185 aggregate_next_hops_fee_msat,
2186 aggregate_path_contribution_msat,
2187 aggregate_next_hops_path_htlc_minimum_msat,
2188 aggregate_next_hops_path_penalty_msat,
2189 aggregate_next_hops_cltv_delta,
2190 aggregate_next_hops_path_length);
2198 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2200 // At this point, targets are filled with the data from first and
2201 // last hops communicated by the caller, and the payment receiver.
2202 let mut found_new_path = false;
2205 // If this loop terminates due the exhaustion of targets, two situations are possible:
2206 // - not enough outgoing liquidity:
2207 // 0 < already_collected_value_msat < final_value_msat
2208 // - enough outgoing liquidity:
2209 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2210 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2211 // paths_collection will be stopped because found_new_path==false.
2212 // This is not necessarily a routing failure.
2213 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, mut value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, path_length_to_node, .. }) = targets.pop() {
2215 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2216 // traversing the graph and arrange the path out of what we found.
2217 if node_id == our_node_id {
2218 let mut new_entry = dist.remove(&our_node_id).unwrap();
2219 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2222 let mut features_set = false;
2223 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2224 for details in first_channels {
2225 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2226 if details.get_outbound_payment_scid().unwrap() == scid {
2227 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2228 features_set = true;
2235 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2236 if let Some(node_info) = node.announcement_info.as_ref() {
2237 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2239 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2242 // We can fill in features for everything except hops which were
2243 // provided via the invoice we're paying. We could guess based on the
2244 // recipient's features but for now we simply avoid guessing at all.
2248 // Means we succesfully traversed from the payer to the payee, now
2249 // save this path for the payment route. Also, update the liquidity
2250 // remaining on the used hops, so that we take them into account
2251 // while looking for more paths.
2252 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2256 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2257 Some(payment_hop) => payment_hop,
2258 // We can't arrive at None because, if we ever add an entry to targets,
2259 // we also fill in the entry in dist (see add_entry!).
2260 None => unreachable!(),
2262 // We "propagate" the fees one hop backward (topologically) here,
2263 // so that fees paid for a HTLC forwarding on the current channel are
2264 // associated with the previous channel (where they will be subtracted).
2265 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2266 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2268 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2269 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2271 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2272 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2274 let mut payment_path = PaymentPath {hops: ordered_hops};
2276 // We could have possibly constructed a slightly inconsistent path: since we reduce
2277 // value being transferred along the way, we could have violated htlc_minimum_msat
2278 // on some channels we already passed (assuming dest->source direction). Here, we
2279 // recompute the fees again, so that if that's the case, we match the currently
2280 // underpaid htlc_minimum_msat with fees.
2281 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2282 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
2283 payment_path.update_value_and_recompute_fees(value_contribution_msat);
2285 // Since a path allows to transfer as much value as
2286 // the smallest channel it has ("bottleneck"), we should recompute
2287 // the fees so sender HTLC don't overpay fees when traversing
2288 // larger channels than the bottleneck. This may happen because
2289 // when we were selecting those channels we were not aware how much value
2290 // this path will transfer, and the relative fee for them
2291 // might have been computed considering a larger value.
2292 // Remember that we used these channels so that we don't rely
2293 // on the same liquidity in future paths.
2294 let mut prevented_redundant_path_selection = false;
2295 let prev_hop_iter = core::iter::once(&our_node_id)
2296 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2297 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2298 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2299 let used_liquidity_msat = used_liquidities
2300 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2301 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2302 .or_insert(spent_on_hop_msat);
2303 let hop_capacity = hop.candidate.effective_capacity();
2304 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2305 if *used_liquidity_msat == hop_max_msat {
2306 // If this path used all of this channel's available liquidity, we know
2307 // this path will not be selected again in the next loop iteration.
2308 prevented_redundant_path_selection = true;
2310 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2312 if !prevented_redundant_path_selection {
2313 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2314 // we'll probably end up picking the same path again on the next iteration.
2315 // Decrease the available liquidity of a hop in the middle of the path.
2316 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2317 let exhausted = u64::max_value();
2319 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2320 LoggedCandidateHop(victim_candidate));
2321 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2322 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2325 // Track the total amount all our collected paths allow to send so that we know
2326 // when to stop looking for more paths
2327 already_collected_value_msat += value_contribution_msat;
2329 payment_paths.push(payment_path);
2330 found_new_path = true;
2331 break 'path_construction;
2334 // If we found a path back to the payee, we shouldn't try to process it again. This is
2335 // the equivalent of the `elem.was_processed` check in
2336 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2337 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2339 // Otherwise, since the current target node is not us,
2340 // keep "unrolling" the payment graph from payee to payer by
2341 // finding a way to reach the current target from the payer side.
2342 match network_nodes.get(&node_id) {
2345 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2346 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2347 total_cltv_delta, path_length_to_node);
2353 if !found_new_path && channel_saturation_pow_half != 0 {
2354 channel_saturation_pow_half = 0;
2355 continue 'paths_collection;
2357 // If we don't support MPP, no use trying to gather more value ever.
2358 break 'paths_collection;
2362 // Stop either when the recommended value is reached or if no new path was found in this
2364 // In the latter case, making another path finding attempt won't help,
2365 // because we deterministically terminated the search due to low liquidity.
2366 if !found_new_path && channel_saturation_pow_half != 0 {
2367 channel_saturation_pow_half = 0;
2368 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2369 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2370 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2371 break 'paths_collection;
2372 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2373 // Further, if this was our first walk of the graph, and we weren't limited by an
2374 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2375 // limited by an htlc_minimum_msat value, find another path with a higher value,
2376 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2377 // still keeping a lower total fee than this path.
2378 if !hit_minimum_limit {
2379 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2380 break 'paths_collection;
2382 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
2383 path_value_msat = recommended_value_msat;
2387 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2388 num_ignored_cltv_delta_limit + num_ignored_previously_failed;
2389 if num_ignored_total > 0 {
2390 log_trace!(logger, "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure. Total: {} ignored candidates.", num_ignored_value_contribution, num_ignored_path_length_limit, num_ignored_cltv_delta_limit, num_ignored_previously_failed, num_ignored_total);
2394 if payment_paths.len() == 0 {
2395 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2398 if already_collected_value_msat < final_value_msat {
2399 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2403 let mut selected_route = payment_paths;
2405 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2406 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2408 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2409 // the value they contribute towards the payment amount.
2410 // We sort in descending order as we will remove from the front in `retain`, next.
2411 selected_route.sort_unstable_by(|a, b|
2412 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2413 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2416 // We should make sure that at least 1 path left.
2417 let mut paths_left = selected_route.len();
2418 selected_route.retain(|path| {
2419 if paths_left == 1 {
2422 let path_value_msat = path.get_value_msat();
2423 if path_value_msat <= overpaid_value_msat {
2424 overpaid_value_msat -= path_value_msat;
2430 debug_assert!(selected_route.len() > 0);
2432 if overpaid_value_msat != 0 {
2434 // Now, subtract the remaining overpaid value from the most-expensive path.
2435 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2436 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2437 selected_route.sort_unstable_by(|a, b| {
2438 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2439 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2440 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2442 let expensive_payment_path = selected_route.first_mut().unwrap();
2444 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2445 // can't go negative.
2446 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2447 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2451 // Sort by the path itself and combine redundant paths.
2452 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2453 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2455 selected_route.sort_unstable_by_key(|path| {
2456 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2457 debug_assert!(path.hops.len() <= key.len());
2458 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2463 for idx in 0..(selected_route.len() - 1) {
2464 if idx + 1 >= selected_route.len() { break; }
2465 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2466 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2467 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2468 selected_route[idx].update_value_and_recompute_fees(new_value);
2469 selected_route.remove(idx + 1);
2473 let mut paths = Vec::new();
2474 for payment_path in selected_route {
2475 let mut hops = Vec::with_capacity(payment_path.hops.len());
2476 for (hop, node_features) in payment_path.hops.iter()
2477 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2479 hops.push(RouteHop {
2480 pubkey: PublicKey::from_slice(hop.node_id.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &hop.node_id), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
2481 node_features: node_features.clone(),
2482 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2483 channel_features: hop.candidate.features(),
2484 fee_msat: hop.fee_msat,
2485 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2488 let mut final_cltv_delta = final_cltv_expiry_delta;
2489 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2490 if let Some(blinded_path) = h.candidate.blinded_path() {
2491 final_cltv_delta = h.candidate.cltv_expiry_delta();
2493 hops: blinded_path.blinded_hops.clone(),
2494 blinding_point: blinded_path.blinding_point,
2495 excess_final_cltv_expiry_delta: 0,
2496 final_value_msat: h.fee_msat,
2500 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2501 // applicable for the previous hop.
2502 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2503 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2506 paths.push(Path { hops, blinded_tail });
2508 // Make sure we would never create a route with more paths than we allow.
2509 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2511 if let Some(node_features) = payment_params.payee.node_features() {
2512 for path in paths.iter_mut() {
2513 path.hops.last_mut().unwrap().node_features = node_features.clone();
2517 let route = Route { paths, route_params: Some(route_params.clone()) };
2518 log_info!(logger, "Got route: {}", log_route!(route));
2522 // When an adversarial intermediary node observes a payment, it may be able to infer its
2523 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2524 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2525 // payment path by adding a randomized 'shadow route' offset to the final hop.
2526 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2527 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2529 let network_channels = network_graph.channels();
2530 let network_nodes = network_graph.nodes();
2532 for path in route.paths.iter_mut() {
2533 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2535 // Remember the last three nodes of the random walk and avoid looping back on them.
2536 // Init with the last three nodes from the actual path, if possible.
2537 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2538 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2539 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2541 // Choose the last publicly known node as the starting point for the random walk.
2542 let mut cur_hop: Option<NodeId> = None;
2543 let mut path_nonce = [0u8; 12];
2544 if let Some(starting_hop) = path.hops.iter().rev()
2545 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2546 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2547 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2550 // Init PRNG with the path-dependant nonce, which is static for private paths.
2551 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2552 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2554 // Pick a random path length in [1 .. 3]
2555 prng.process_in_place(&mut random_path_bytes);
2556 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2558 for random_hop in 0..random_walk_length {
2559 // If we don't find a suitable offset in the public network graph, we default to
2560 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2561 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2563 if let Some(cur_node_id) = cur_hop {
2564 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2565 // Randomly choose the next unvisited hop.
2566 prng.process_in_place(&mut random_path_bytes);
2567 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2568 .checked_rem(cur_node.channels.len())
2569 .and_then(|index| cur_node.channels.get(index))
2570 .and_then(|id| network_channels.get(id)) {
2571 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2572 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2573 nodes_to_avoid[random_hop] = *next_id;
2574 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2575 cur_hop = Some(*next_id);
2582 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2583 .checked_add(random_hop_offset)
2584 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2587 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2588 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2589 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2591 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2592 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2593 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2594 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2595 max_path_offset = cmp::max(
2596 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2597 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2598 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2600 // Add 'shadow' CLTV offset to the final hop
2601 if let Some(tail) = path.blinded_tail.as_mut() {
2602 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2603 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2605 if let Some(last_hop) = path.hops.last_mut() {
2606 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2607 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2612 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2613 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2615 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2616 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2617 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2618 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2619 ) -> Result<Route, LightningError>
2620 where L::Target: Logger, GL::Target: Logger {
2621 let graph_lock = network_graph.read_only();
2622 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2623 &graph_lock, logger, random_seed_bytes)?;
2624 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2628 fn build_route_from_hops_internal<L: Deref>(
2629 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2630 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2631 ) -> Result<Route, LightningError> where L::Target: Logger {
2634 our_node_id: NodeId,
2635 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2638 impl ScoreLookUp for HopScorer {
2639 type ScoreParams = ();
2640 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2641 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2643 let mut cur_id = self.our_node_id;
2644 for i in 0..self.hop_ids.len() {
2645 if let Some(next_id) = self.hop_ids[i] {
2646 if cur_id == *source && next_id == *target {
2658 impl<'a> Writeable for HopScorer {
2660 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2665 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2666 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2669 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2670 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2671 for i in 0..hops.len() {
2672 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2675 let scorer = HopScorer { our_node_id, hop_ids };
2677 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &(), random_seed_bytes)
2682 use crate::blinded_path::{BlindedHop, BlindedPath};
2683 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2684 use crate::routing::utxo::UtxoResult;
2685 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2686 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2687 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2688 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2689 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2690 use crate::chain::transaction::OutPoint;
2691 use crate::sign::EntropySource;
2692 use crate::ln::ChannelId;
2693 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2694 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2695 use crate::ln::channelmanager;
2696 use crate::offers::invoice::BlindedPayInfo;
2697 use crate::util::config::UserConfig;
2698 use crate::util::test_utils as ln_test_utils;
2699 use crate::util::chacha20::ChaCha20;
2700 use crate::util::ser::{Readable, Writeable};
2702 use crate::util::ser::Writer;
2704 use bitcoin::hashes::Hash;
2705 use bitcoin::network::constants::Network;
2706 use bitcoin::blockdata::constants::genesis_block;
2707 use bitcoin::blockdata::script::Builder;
2708 use bitcoin::blockdata::opcodes;
2709 use bitcoin::blockdata::transaction::TxOut;
2713 use bitcoin::secp256k1::{PublicKey,SecretKey};
2714 use bitcoin::secp256k1::Secp256k1;
2716 use crate::io::Cursor;
2717 use crate::prelude::*;
2718 use crate::sync::Arc;
2720 use core::convert::TryInto;
2722 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2723 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2724 channelmanager::ChannelDetails {
2725 channel_id: ChannelId::new_zero(),
2726 counterparty: channelmanager::ChannelCounterparty {
2729 unspendable_punishment_reserve: 0,
2730 forwarding_info: None,
2731 outbound_htlc_minimum_msat: None,
2732 outbound_htlc_maximum_msat: None,
2734 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2737 outbound_scid_alias: None,
2738 inbound_scid_alias: None,
2739 channel_value_satoshis: 0,
2741 outbound_capacity_msat,
2742 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2743 next_outbound_htlc_minimum_msat: 0,
2744 inbound_capacity_msat: 42,
2745 unspendable_punishment_reserve: None,
2746 confirmations_required: None,
2747 confirmations: None,
2748 force_close_spend_delay: None,
2749 is_outbound: true, is_channel_ready: true,
2750 is_usable: true, is_public: true,
2751 inbound_htlc_minimum_msat: None,
2752 inbound_htlc_maximum_msat: None,
2754 feerate_sat_per_1000_weight: None,
2755 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2760 fn simple_route_test() {
2761 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2762 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2763 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2764 let scorer = ln_test_utils::TestScorer::new();
2765 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2766 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2768 // Simple route to 2 via 1
2770 let route_params = RouteParameters::from_payment_params_and_value(
2771 payment_params.clone(), 0);
2772 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2773 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
2774 &random_seed_bytes) {
2775 assert_eq!(err, "Cannot send a payment of 0 msat");
2776 } else { panic!(); }
2778 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2779 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2780 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2781 assert_eq!(route.paths[0].hops.len(), 2);
2783 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2784 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2785 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2786 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2787 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2788 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2790 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2791 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2792 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2793 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2794 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2795 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2799 fn invalid_first_hop_test() {
2800 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2801 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2802 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2803 let scorer = ln_test_utils::TestScorer::new();
2804 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2805 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2807 // Simple route to 2 via 1
2809 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2811 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2812 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2813 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2814 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2815 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2816 } else { panic!(); }
2818 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2819 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2820 assert_eq!(route.paths[0].hops.len(), 2);
2824 fn htlc_minimum_test() {
2825 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2826 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2827 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2828 let scorer = ln_test_utils::TestScorer::new();
2829 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2830 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2832 // Simple route to 2 via 1
2834 // Disable other paths
2835 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2836 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2837 short_channel_id: 12,
2839 flags: 2, // to disable
2840 cltv_expiry_delta: 0,
2841 htlc_minimum_msat: 0,
2842 htlc_maximum_msat: MAX_VALUE_MSAT,
2844 fee_proportional_millionths: 0,
2845 excess_data: Vec::new()
2847 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2848 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2849 short_channel_id: 3,
2851 flags: 2, // to disable
2852 cltv_expiry_delta: 0,
2853 htlc_minimum_msat: 0,
2854 htlc_maximum_msat: MAX_VALUE_MSAT,
2856 fee_proportional_millionths: 0,
2857 excess_data: Vec::new()
2859 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2860 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2861 short_channel_id: 13,
2863 flags: 2, // to disable
2864 cltv_expiry_delta: 0,
2865 htlc_minimum_msat: 0,
2866 htlc_maximum_msat: MAX_VALUE_MSAT,
2868 fee_proportional_millionths: 0,
2869 excess_data: Vec::new()
2871 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2872 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2873 short_channel_id: 6,
2875 flags: 2, // to disable
2876 cltv_expiry_delta: 0,
2877 htlc_minimum_msat: 0,
2878 htlc_maximum_msat: MAX_VALUE_MSAT,
2880 fee_proportional_millionths: 0,
2881 excess_data: Vec::new()
2883 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2884 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2885 short_channel_id: 7,
2887 flags: 2, // to disable
2888 cltv_expiry_delta: 0,
2889 htlc_minimum_msat: 0,
2890 htlc_maximum_msat: MAX_VALUE_MSAT,
2892 fee_proportional_millionths: 0,
2893 excess_data: Vec::new()
2896 // Check against amount_to_transfer_over_msat.
2897 // Set minimal HTLC of 200_000_000 msat.
2898 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2899 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2900 short_channel_id: 2,
2903 cltv_expiry_delta: 0,
2904 htlc_minimum_msat: 200_000_000,
2905 htlc_maximum_msat: MAX_VALUE_MSAT,
2907 fee_proportional_millionths: 0,
2908 excess_data: Vec::new()
2911 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2913 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2914 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2915 short_channel_id: 4,
2918 cltv_expiry_delta: 0,
2919 htlc_minimum_msat: 0,
2920 htlc_maximum_msat: 199_999_999,
2922 fee_proportional_millionths: 0,
2923 excess_data: Vec::new()
2926 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2927 let route_params = RouteParameters::from_payment_params_and_value(
2928 payment_params, 199_999_999);
2929 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2930 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
2931 &random_seed_bytes) {
2932 assert_eq!(err, "Failed to find a path to the given destination");
2933 } else { panic!(); }
2935 // Lift the restriction on the first hop.
2936 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2937 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2938 short_channel_id: 2,
2941 cltv_expiry_delta: 0,
2942 htlc_minimum_msat: 0,
2943 htlc_maximum_msat: MAX_VALUE_MSAT,
2945 fee_proportional_millionths: 0,
2946 excess_data: Vec::new()
2949 // A payment above the minimum should pass
2950 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2951 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2952 assert_eq!(route.paths[0].hops.len(), 2);
2956 fn htlc_minimum_overpay_test() {
2957 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2958 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2959 let config = UserConfig::default();
2960 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
2961 let scorer = ln_test_utils::TestScorer::new();
2962 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2963 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2965 // A route to node#2 via two paths.
2966 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2967 // Thus, they can't send 60 without overpaying.
2968 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2969 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2970 short_channel_id: 2,
2973 cltv_expiry_delta: 0,
2974 htlc_minimum_msat: 35_000,
2975 htlc_maximum_msat: 40_000,
2977 fee_proportional_millionths: 0,
2978 excess_data: Vec::new()
2980 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2981 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2982 short_channel_id: 12,
2985 cltv_expiry_delta: 0,
2986 htlc_minimum_msat: 35_000,
2987 htlc_maximum_msat: 40_000,
2989 fee_proportional_millionths: 0,
2990 excess_data: Vec::new()
2994 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2995 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2996 short_channel_id: 13,
2999 cltv_expiry_delta: 0,
3000 htlc_minimum_msat: 0,
3001 htlc_maximum_msat: MAX_VALUE_MSAT,
3003 fee_proportional_millionths: 0,
3004 excess_data: Vec::new()
3006 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3008 short_channel_id: 4,
3011 cltv_expiry_delta: 0,
3012 htlc_minimum_msat: 0,
3013 htlc_maximum_msat: MAX_VALUE_MSAT,
3015 fee_proportional_millionths: 0,
3016 excess_data: Vec::new()
3019 // Disable other paths
3020 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3021 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3022 short_channel_id: 1,
3024 flags: 2, // to disable
3025 cltv_expiry_delta: 0,
3026 htlc_minimum_msat: 0,
3027 htlc_maximum_msat: MAX_VALUE_MSAT,
3029 fee_proportional_millionths: 0,
3030 excess_data: Vec::new()
3033 let route_params = RouteParameters::from_payment_params_and_value(
3034 payment_params.clone(), 60_000);
3035 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3036 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3037 // Overpay fees to hit htlc_minimum_msat.
3038 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3039 // TODO: this could be better balanced to overpay 10k and not 15k.
3040 assert_eq!(overpaid_fees, 15_000);
3042 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3043 // while taking even more fee to match htlc_minimum_msat.
3044 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3045 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3046 short_channel_id: 12,
3049 cltv_expiry_delta: 0,
3050 htlc_minimum_msat: 65_000,
3051 htlc_maximum_msat: 80_000,
3053 fee_proportional_millionths: 0,
3054 excess_data: Vec::new()
3056 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3057 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3058 short_channel_id: 2,
3061 cltv_expiry_delta: 0,
3062 htlc_minimum_msat: 0,
3063 htlc_maximum_msat: MAX_VALUE_MSAT,
3065 fee_proportional_millionths: 0,
3066 excess_data: Vec::new()
3068 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3069 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3070 short_channel_id: 4,
3073 cltv_expiry_delta: 0,
3074 htlc_minimum_msat: 0,
3075 htlc_maximum_msat: MAX_VALUE_MSAT,
3077 fee_proportional_millionths: 100_000,
3078 excess_data: Vec::new()
3081 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3082 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3083 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3084 assert_eq!(route.paths.len(), 1);
3085 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3086 let fees = route.paths[0].hops[0].fee_msat;
3087 assert_eq!(fees, 5_000);
3089 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3090 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3091 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3092 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3093 // the other channel.
3094 assert_eq!(route.paths.len(), 1);
3095 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3096 let fees = route.paths[0].hops[0].fee_msat;
3097 assert_eq!(fees, 5_000);
3101 fn disable_channels_test() {
3102 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3103 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3104 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3105 let scorer = ln_test_utils::TestScorer::new();
3106 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3107 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3109 // // Disable channels 4 and 12 by flags=2
3110 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3111 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3112 short_channel_id: 4,
3114 flags: 2, // to disable
3115 cltv_expiry_delta: 0,
3116 htlc_minimum_msat: 0,
3117 htlc_maximum_msat: MAX_VALUE_MSAT,
3119 fee_proportional_millionths: 0,
3120 excess_data: Vec::new()
3122 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3123 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3124 short_channel_id: 12,
3126 flags: 2, // to disable
3127 cltv_expiry_delta: 0,
3128 htlc_minimum_msat: 0,
3129 htlc_maximum_msat: MAX_VALUE_MSAT,
3131 fee_proportional_millionths: 0,
3132 excess_data: Vec::new()
3135 // If all the channels require some features we don't understand, route should fail
3136 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3137 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3138 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3139 &random_seed_bytes) {
3140 assert_eq!(err, "Failed to find a path to the given destination");
3141 } else { panic!(); }
3143 // If we specify a channel to node7, that overrides our local channel view and that gets used
3144 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3145 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3146 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3147 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3148 &random_seed_bytes).unwrap();
3149 assert_eq!(route.paths[0].hops.len(), 2);
3151 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3152 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3153 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3154 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3155 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3156 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3158 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3159 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3160 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3161 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3162 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3163 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3167 fn disable_node_test() {
3168 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3169 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3170 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3171 let scorer = ln_test_utils::TestScorer::new();
3172 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3173 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3175 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3176 let mut unknown_features = NodeFeatures::empty();
3177 unknown_features.set_unknown_feature_required();
3178 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3179 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3180 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3182 // If all nodes require some features we don't understand, route should fail
3183 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3184 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3185 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3186 &random_seed_bytes) {
3187 assert_eq!(err, "Failed to find a path to the given destination");
3188 } else { panic!(); }
3190 // If we specify a channel to node7, that overrides our local channel view and that gets used
3191 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3192 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3193 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3194 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3195 &random_seed_bytes).unwrap();
3196 assert_eq!(route.paths[0].hops.len(), 2);
3198 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3199 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3200 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3201 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3202 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3203 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3205 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3206 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3207 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3208 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3209 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3210 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3212 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3213 // naively) assume that the user checked the feature bits on the invoice, which override
3214 // the node_announcement.
3218 fn our_chans_test() {
3219 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3220 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3221 let scorer = ln_test_utils::TestScorer::new();
3222 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3223 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3225 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3226 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3227 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3228 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3229 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3230 assert_eq!(route.paths[0].hops.len(), 3);
3232 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3233 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3234 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3235 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3236 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3237 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3239 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3240 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3241 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3242 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3243 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3244 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3246 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3247 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3248 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3249 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3250 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3251 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3253 // If we specify a channel to node7, that overrides our local channel view and that gets used
3254 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3255 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3256 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3257 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3258 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3259 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3260 &random_seed_bytes).unwrap();
3261 assert_eq!(route.paths[0].hops.len(), 2);
3263 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3264 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3265 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3266 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3267 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3268 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3270 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3271 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3272 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3273 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3274 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3275 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3278 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3279 let zero_fees = RoutingFees {
3281 proportional_millionths: 0,
3283 vec![RouteHint(vec![RouteHintHop {
3284 src_node_id: nodes[3],
3285 short_channel_id: 8,
3287 cltv_expiry_delta: (8 << 4) | 1,
3288 htlc_minimum_msat: None,
3289 htlc_maximum_msat: None,
3291 ]), RouteHint(vec![RouteHintHop {
3292 src_node_id: nodes[4],
3293 short_channel_id: 9,
3296 proportional_millionths: 0,
3298 cltv_expiry_delta: (9 << 4) | 1,
3299 htlc_minimum_msat: None,
3300 htlc_maximum_msat: None,
3301 }]), RouteHint(vec![RouteHintHop {
3302 src_node_id: nodes[5],
3303 short_channel_id: 10,
3305 cltv_expiry_delta: (10 << 4) | 1,
3306 htlc_minimum_msat: None,
3307 htlc_maximum_msat: None,
3311 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3312 let zero_fees = RoutingFees {
3314 proportional_millionths: 0,
3316 vec![RouteHint(vec![RouteHintHop {
3317 src_node_id: nodes[2],
3318 short_channel_id: 5,
3321 proportional_millionths: 0,
3323 cltv_expiry_delta: (5 << 4) | 1,
3324 htlc_minimum_msat: None,
3325 htlc_maximum_msat: None,
3327 src_node_id: nodes[3],
3328 short_channel_id: 8,
3330 cltv_expiry_delta: (8 << 4) | 1,
3331 htlc_minimum_msat: None,
3332 htlc_maximum_msat: None,
3334 ]), RouteHint(vec![RouteHintHop {
3335 src_node_id: nodes[4],
3336 short_channel_id: 9,
3339 proportional_millionths: 0,
3341 cltv_expiry_delta: (9 << 4) | 1,
3342 htlc_minimum_msat: None,
3343 htlc_maximum_msat: None,
3344 }]), RouteHint(vec![RouteHintHop {
3345 src_node_id: nodes[5],
3346 short_channel_id: 10,
3348 cltv_expiry_delta: (10 << 4) | 1,
3349 htlc_minimum_msat: None,
3350 htlc_maximum_msat: None,
3355 fn partial_route_hint_test() {
3356 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3357 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3358 let scorer = ln_test_utils::TestScorer::new();
3359 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3360 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3362 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3363 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3364 // RouteHint may be partially used by the algo to build the best path.
3366 // First check that last hop can't have its source as the payee.
3367 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3368 src_node_id: nodes[6],
3369 short_channel_id: 8,
3372 proportional_millionths: 0,
3374 cltv_expiry_delta: (8 << 4) | 1,
3375 htlc_minimum_msat: None,
3376 htlc_maximum_msat: None,
3379 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3380 invalid_last_hops.push(invalid_last_hop);
3382 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3383 .with_route_hints(invalid_last_hops).unwrap();
3384 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3385 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3386 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3387 &random_seed_bytes) {
3388 assert_eq!(err, "Route hint cannot have the payee as the source.");
3389 } else { panic!(); }
3392 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3393 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3394 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3395 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3396 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3397 assert_eq!(route.paths[0].hops.len(), 5);
3399 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3400 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3401 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3402 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3403 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3404 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3406 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3407 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3408 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3409 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3410 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3411 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3413 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3414 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3415 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3416 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3417 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3418 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3420 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3421 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3422 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3423 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3424 // If we have a peer in the node map, we'll use their features here since we don't have
3425 // a way of figuring out their features from the invoice:
3426 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3427 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3429 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3430 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3431 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3432 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3433 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3434 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3437 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3438 let zero_fees = RoutingFees {
3440 proportional_millionths: 0,
3442 vec![RouteHint(vec![RouteHintHop {
3443 src_node_id: nodes[3],
3444 short_channel_id: 8,
3446 cltv_expiry_delta: (8 << 4) | 1,
3447 htlc_minimum_msat: None,
3448 htlc_maximum_msat: None,
3449 }]), RouteHint(vec![
3451 ]), RouteHint(vec![RouteHintHop {
3452 src_node_id: nodes[5],
3453 short_channel_id: 10,
3455 cltv_expiry_delta: (10 << 4) | 1,
3456 htlc_minimum_msat: None,
3457 htlc_maximum_msat: None,
3462 fn ignores_empty_last_hops_test() {
3463 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3464 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3465 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3466 let scorer = ln_test_utils::TestScorer::new();
3467 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3468 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3470 // Test handling of an empty RouteHint passed in Invoice.
3471 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3472 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3473 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3474 assert_eq!(route.paths[0].hops.len(), 5);
3476 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3477 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3478 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3479 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3480 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3481 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3483 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3484 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3485 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3486 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3487 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3488 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3490 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3491 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3492 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3493 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3494 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3495 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3497 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3498 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3499 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3500 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3501 // If we have a peer in the node map, we'll use their features here since we don't have
3502 // a way of figuring out their features from the invoice:
3503 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3504 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3506 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3507 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3508 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3509 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3510 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3511 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3514 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3516 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3517 let zero_fees = RoutingFees {
3519 proportional_millionths: 0,
3521 vec![RouteHint(vec![RouteHintHop {
3522 src_node_id: hint_hops[0],
3523 short_channel_id: 0xff00,
3526 proportional_millionths: 0,
3528 cltv_expiry_delta: (5 << 4) | 1,
3529 htlc_minimum_msat: None,
3530 htlc_maximum_msat: None,
3532 src_node_id: hint_hops[1],
3533 short_channel_id: 0xff01,
3535 cltv_expiry_delta: (8 << 4) | 1,
3536 htlc_minimum_msat: None,
3537 htlc_maximum_msat: None,
3542 fn multi_hint_last_hops_test() {
3543 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3544 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3545 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3546 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3547 let scorer = ln_test_utils::TestScorer::new();
3548 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3549 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3550 // Test through channels 2, 3, 0xff00, 0xff01.
3551 // Test shows that multiple hop hints are considered.
3553 // Disabling channels 6 & 7 by flags=2
3554 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3555 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3556 short_channel_id: 6,
3558 flags: 2, // to disable
3559 cltv_expiry_delta: 0,
3560 htlc_minimum_msat: 0,
3561 htlc_maximum_msat: MAX_VALUE_MSAT,
3563 fee_proportional_millionths: 0,
3564 excess_data: Vec::new()
3566 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3567 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3568 short_channel_id: 7,
3570 flags: 2, // to disable
3571 cltv_expiry_delta: 0,
3572 htlc_minimum_msat: 0,
3573 htlc_maximum_msat: MAX_VALUE_MSAT,
3575 fee_proportional_millionths: 0,
3576 excess_data: Vec::new()
3579 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3580 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3581 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3582 assert_eq!(route.paths[0].hops.len(), 4);
3584 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3585 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3586 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3587 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3588 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3589 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3591 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3592 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3593 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3594 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3595 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3596 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3598 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3599 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3600 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3601 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3602 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3603 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3605 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3606 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3607 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3608 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3609 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3610 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3614 fn private_multi_hint_last_hops_test() {
3615 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3616 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3618 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3619 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3621 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3622 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3623 let scorer = ln_test_utils::TestScorer::new();
3624 // Test through channels 2, 3, 0xff00, 0xff01.
3625 // Test shows that multiple hop hints are considered.
3627 // Disabling channels 6 & 7 by flags=2
3628 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3629 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3630 short_channel_id: 6,
3632 flags: 2, // to disable
3633 cltv_expiry_delta: 0,
3634 htlc_minimum_msat: 0,
3635 htlc_maximum_msat: MAX_VALUE_MSAT,
3637 fee_proportional_millionths: 0,
3638 excess_data: Vec::new()
3640 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3641 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3642 short_channel_id: 7,
3644 flags: 2, // to disable
3645 cltv_expiry_delta: 0,
3646 htlc_minimum_msat: 0,
3647 htlc_maximum_msat: MAX_VALUE_MSAT,
3649 fee_proportional_millionths: 0,
3650 excess_data: Vec::new()
3653 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3654 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3655 Arc::clone(&logger), &scorer, &(), &[42u8; 32]).unwrap();
3656 assert_eq!(route.paths[0].hops.len(), 4);
3658 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3659 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3660 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3661 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3662 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3663 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3665 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3666 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3667 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3668 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3669 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3670 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3672 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3673 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3674 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3675 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3676 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3677 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3679 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3680 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3681 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3682 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3683 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3684 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3687 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3688 let zero_fees = RoutingFees {
3690 proportional_millionths: 0,
3692 vec![RouteHint(vec![RouteHintHop {
3693 src_node_id: nodes[4],
3694 short_channel_id: 11,
3696 cltv_expiry_delta: (11 << 4) | 1,
3697 htlc_minimum_msat: None,
3698 htlc_maximum_msat: None,
3700 src_node_id: nodes[3],
3701 short_channel_id: 8,
3703 cltv_expiry_delta: (8 << 4) | 1,
3704 htlc_minimum_msat: None,
3705 htlc_maximum_msat: None,
3706 }]), RouteHint(vec![RouteHintHop {
3707 src_node_id: nodes[4],
3708 short_channel_id: 9,
3711 proportional_millionths: 0,
3713 cltv_expiry_delta: (9 << 4) | 1,
3714 htlc_minimum_msat: None,
3715 htlc_maximum_msat: None,
3716 }]), RouteHint(vec![RouteHintHop {
3717 src_node_id: nodes[5],
3718 short_channel_id: 10,
3720 cltv_expiry_delta: (10 << 4) | 1,
3721 htlc_minimum_msat: None,
3722 htlc_maximum_msat: None,
3727 fn last_hops_with_public_channel_test() {
3728 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3729 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3730 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3731 let scorer = ln_test_utils::TestScorer::new();
3732 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3733 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3734 // This test shows that public routes can be present in the invoice
3735 // which would be handled in the same manner.
3737 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3738 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3739 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3740 assert_eq!(route.paths[0].hops.len(), 5);
3742 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3743 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3744 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3745 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3746 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3747 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3749 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3750 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3751 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3752 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3753 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3754 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3756 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3757 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3758 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3759 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3760 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3761 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3763 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3764 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3765 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3766 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3767 // If we have a peer in the node map, we'll use their features here since we don't have
3768 // a way of figuring out their features from the invoice:
3769 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3770 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3772 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3773 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3774 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3775 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3776 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3777 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3781 fn our_chans_last_hop_connect_test() {
3782 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3783 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3784 let scorer = ln_test_utils::TestScorer::new();
3785 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3786 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3788 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3789 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3790 let mut last_hops = last_hops(&nodes);
3791 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3792 .with_route_hints(last_hops.clone()).unwrap();
3793 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3794 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3795 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3796 &random_seed_bytes).unwrap();
3797 assert_eq!(route.paths[0].hops.len(), 2);
3799 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3800 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3801 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3802 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3803 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3804 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3806 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3807 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3808 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3809 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3810 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3811 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3813 last_hops[0].0[0].fees.base_msat = 1000;
3815 // Revert to via 6 as the fee on 8 goes up
3816 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3817 .with_route_hints(last_hops).unwrap();
3818 let route_params = RouteParameters::from_payment_params_and_value(
3819 payment_params.clone(), 100);
3820 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3821 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3822 assert_eq!(route.paths[0].hops.len(), 4);
3824 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3825 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3826 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3827 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3828 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3829 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3831 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3832 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3833 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3834 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3835 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3836 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3838 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3839 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3840 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3841 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3842 // If we have a peer in the node map, we'll use their features here since we don't have
3843 // a way of figuring out their features from the invoice:
3844 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3845 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3847 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3848 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3849 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3850 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3851 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3852 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3854 // ...but still use 8 for larger payments as 6 has a variable feerate
3855 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
3856 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3857 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3858 assert_eq!(route.paths[0].hops.len(), 5);
3860 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3861 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3862 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3863 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3864 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3865 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3867 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3868 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3869 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3870 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3871 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3872 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3874 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3875 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3876 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3877 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3878 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3879 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3881 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3882 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3883 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
3884 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3885 // If we have a peer in the node map, we'll use their features here since we don't have
3886 // a way of figuring out their features from the invoice:
3887 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3888 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3890 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3891 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3892 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
3893 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3894 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3895 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3898 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> {
3899 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3900 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3901 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3903 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3904 let last_hops = RouteHint(vec![RouteHintHop {
3905 src_node_id: middle_node_id,
3906 short_channel_id: 8,
3909 proportional_millionths: last_hop_fee_prop,
3911 cltv_expiry_delta: (8 << 4) | 1,
3912 htlc_minimum_msat: None,
3913 htlc_maximum_msat: last_hop_htlc_max,
3915 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
3916 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3917 let scorer = ln_test_utils::TestScorer::new();
3918 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3919 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3920 let logger = ln_test_utils::TestLogger::new();
3921 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
3922 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
3923 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
3924 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &(),
3925 &random_seed_bytes);
3930 fn unannounced_path_test() {
3931 // We should be able to send a payment to a destination without any help of a routing graph
3932 // if we have a channel with a common counterparty that appears in the first and last hop
3934 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3936 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3937 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3938 assert_eq!(route.paths[0].hops.len(), 2);
3940 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
3941 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3942 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
3943 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3944 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
3945 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3947 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
3948 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3949 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
3950 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3951 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3952 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3956 fn overflow_unannounced_path_test_liquidity_underflow() {
3957 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3958 // the last-hop had a fee which overflowed a u64, we'd panic.
3959 // This was due to us adding the first-hop from us unconditionally, causing us to think
3960 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3961 // In this test, we previously hit a subtraction underflow due to having less available
3962 // liquidity at the last hop than 0.
3963 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());
3967 fn overflow_unannounced_path_test_feerate_overflow() {
3968 // This tests for the same case as above, except instead of hitting a subtraction
3969 // underflow, we hit a case where the fee charged at a hop overflowed.
3970 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());
3974 fn available_amount_while_routing_test() {
3975 // Tests whether we choose the correct available channel amount while routing.
3977 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
3978 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3979 let scorer = ln_test_utils::TestScorer::new();
3980 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3981 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3982 let config = UserConfig::default();
3983 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3985 // We will use a simple single-path route from
3986 // our node to node2 via node0: channels {1, 3}.
3988 // First disable all other paths.
3989 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3990 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3991 short_channel_id: 2,
3994 cltv_expiry_delta: 0,
3995 htlc_minimum_msat: 0,
3996 htlc_maximum_msat: 100_000,
3998 fee_proportional_millionths: 0,
3999 excess_data: Vec::new()
4001 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4002 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4003 short_channel_id: 12,
4006 cltv_expiry_delta: 0,
4007 htlc_minimum_msat: 0,
4008 htlc_maximum_msat: 100_000,
4010 fee_proportional_millionths: 0,
4011 excess_data: Vec::new()
4014 // Make the first channel (#1) very permissive,
4015 // and we will be testing all limits on the second channel.
4016 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4017 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4018 short_channel_id: 1,
4021 cltv_expiry_delta: 0,
4022 htlc_minimum_msat: 0,
4023 htlc_maximum_msat: 1_000_000_000,
4025 fee_proportional_millionths: 0,
4026 excess_data: Vec::new()
4029 // First, let's see if routing works if we have absolutely no idea about the available amount.
4030 // In this case, it should be set to 250_000 sats.
4031 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4032 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4033 short_channel_id: 3,
4036 cltv_expiry_delta: 0,
4037 htlc_minimum_msat: 0,
4038 htlc_maximum_msat: 250_000_000,
4040 fee_proportional_millionths: 0,
4041 excess_data: Vec::new()
4045 // Attempt to route more than available results in a failure.
4046 let route_params = RouteParameters::from_payment_params_and_value(
4047 payment_params.clone(), 250_000_001);
4048 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4049 &our_id, &route_params, &network_graph.read_only(), None,
4050 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4051 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4052 } else { panic!(); }
4056 // Now, attempt to route an exact amount we have should be fine.
4057 let route_params = RouteParameters::from_payment_params_and_value(
4058 payment_params.clone(), 250_000_000);
4059 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4060 Arc::clone(&logger), &scorer, &(),&random_seed_bytes).unwrap();
4061 assert_eq!(route.paths.len(), 1);
4062 let path = route.paths.last().unwrap();
4063 assert_eq!(path.hops.len(), 2);
4064 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4065 assert_eq!(path.final_value_msat(), 250_000_000);
4068 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4069 // Disable channel #1 and use another first hop.
4070 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4071 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4072 short_channel_id: 1,
4075 cltv_expiry_delta: 0,
4076 htlc_minimum_msat: 0,
4077 htlc_maximum_msat: 1_000_000_000,
4079 fee_proportional_millionths: 0,
4080 excess_data: Vec::new()
4083 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4084 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4087 // Attempt to route more than available results in a failure.
4088 let route_params = RouteParameters::from_payment_params_and_value(
4089 payment_params.clone(), 200_000_001);
4090 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4091 &our_id, &route_params, &network_graph.read_only(),
4092 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4093 &(), &random_seed_bytes) {
4094 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4095 } else { panic!(); }
4099 // Now, attempt to route an exact amount we have should be fine.
4100 let route_params = RouteParameters::from_payment_params_and_value(
4101 payment_params.clone(), 200_000_000);
4102 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4103 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
4104 &random_seed_bytes).unwrap();
4105 assert_eq!(route.paths.len(), 1);
4106 let path = route.paths.last().unwrap();
4107 assert_eq!(path.hops.len(), 2);
4108 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4109 assert_eq!(path.final_value_msat(), 200_000_000);
4112 // Enable channel #1 back.
4113 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4114 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4115 short_channel_id: 1,
4118 cltv_expiry_delta: 0,
4119 htlc_minimum_msat: 0,
4120 htlc_maximum_msat: 1_000_000_000,
4122 fee_proportional_millionths: 0,
4123 excess_data: Vec::new()
4127 // Now let's see if routing works if we know only htlc_maximum_msat.
4128 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4129 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4130 short_channel_id: 3,
4133 cltv_expiry_delta: 0,
4134 htlc_minimum_msat: 0,
4135 htlc_maximum_msat: 15_000,
4137 fee_proportional_millionths: 0,
4138 excess_data: Vec::new()
4142 // Attempt to route more than available results in a failure.
4143 let route_params = RouteParameters::from_payment_params_and_value(
4144 payment_params.clone(), 15_001);
4145 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4146 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4147 &scorer, &(), &random_seed_bytes) {
4148 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4149 } else { panic!(); }
4153 // Now, attempt to route an exact amount we have should be fine.
4154 let route_params = RouteParameters::from_payment_params_and_value(
4155 payment_params.clone(), 15_000);
4156 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4157 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4158 assert_eq!(route.paths.len(), 1);
4159 let path = route.paths.last().unwrap();
4160 assert_eq!(path.hops.len(), 2);
4161 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4162 assert_eq!(path.final_value_msat(), 15_000);
4165 // Now let's see if routing works if we know only capacity from the UTXO.
4167 // We can't change UTXO capacity on the fly, so we'll disable
4168 // the existing channel and add another one with the capacity we need.
4169 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4170 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4171 short_channel_id: 3,
4174 cltv_expiry_delta: 0,
4175 htlc_minimum_msat: 0,
4176 htlc_maximum_msat: MAX_VALUE_MSAT,
4178 fee_proportional_millionths: 0,
4179 excess_data: Vec::new()
4182 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4183 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4184 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4185 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4186 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4188 *chain_monitor.utxo_ret.lock().unwrap() =
4189 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4190 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4192 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4193 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4194 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4195 short_channel_id: 333,
4198 cltv_expiry_delta: (3 << 4) | 1,
4199 htlc_minimum_msat: 0,
4200 htlc_maximum_msat: 15_000,
4202 fee_proportional_millionths: 0,
4203 excess_data: Vec::new()
4205 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4206 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4207 short_channel_id: 333,
4210 cltv_expiry_delta: (3 << 4) | 2,
4211 htlc_minimum_msat: 0,
4212 htlc_maximum_msat: 15_000,
4214 fee_proportional_millionths: 0,
4215 excess_data: Vec::new()
4219 // Attempt to route more than available results in a failure.
4220 let route_params = RouteParameters::from_payment_params_and_value(
4221 payment_params.clone(), 15_001);
4222 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4223 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4224 &scorer, &(), &random_seed_bytes) {
4225 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4226 } else { panic!(); }
4230 // Now, attempt to route an exact amount we have should be fine.
4231 let route_params = RouteParameters::from_payment_params_and_value(
4232 payment_params.clone(), 15_000);
4233 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4234 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4235 assert_eq!(route.paths.len(), 1);
4236 let path = route.paths.last().unwrap();
4237 assert_eq!(path.hops.len(), 2);
4238 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4239 assert_eq!(path.final_value_msat(), 15_000);
4242 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4243 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4244 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4245 short_channel_id: 333,
4248 cltv_expiry_delta: 0,
4249 htlc_minimum_msat: 0,
4250 htlc_maximum_msat: 10_000,
4252 fee_proportional_millionths: 0,
4253 excess_data: Vec::new()
4257 // Attempt to route more than available results in a failure.
4258 let route_params = RouteParameters::from_payment_params_and_value(
4259 payment_params.clone(), 10_001);
4260 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4261 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4262 &scorer, &(), &random_seed_bytes) {
4263 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4264 } else { panic!(); }
4268 // Now, attempt to route an exact amount we have should be fine.
4269 let route_params = RouteParameters::from_payment_params_and_value(
4270 payment_params.clone(), 10_000);
4271 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4272 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4273 assert_eq!(route.paths.len(), 1);
4274 let path = route.paths.last().unwrap();
4275 assert_eq!(path.hops.len(), 2);
4276 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4277 assert_eq!(path.final_value_msat(), 10_000);
4282 fn available_liquidity_last_hop_test() {
4283 // Check that available liquidity properly limits the path even when only
4284 // one of the latter hops is limited.
4285 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4286 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4287 let scorer = ln_test_utils::TestScorer::new();
4288 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4289 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4290 let config = UserConfig::default();
4291 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4293 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4294 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4295 // Total capacity: 50 sats.
4297 // Disable other potential paths.
4298 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4299 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4300 short_channel_id: 2,
4303 cltv_expiry_delta: 0,
4304 htlc_minimum_msat: 0,
4305 htlc_maximum_msat: 100_000,
4307 fee_proportional_millionths: 0,
4308 excess_data: Vec::new()
4310 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4311 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4312 short_channel_id: 7,
4315 cltv_expiry_delta: 0,
4316 htlc_minimum_msat: 0,
4317 htlc_maximum_msat: 100_000,
4319 fee_proportional_millionths: 0,
4320 excess_data: Vec::new()
4325 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4326 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4327 short_channel_id: 12,
4330 cltv_expiry_delta: 0,
4331 htlc_minimum_msat: 0,
4332 htlc_maximum_msat: 100_000,
4334 fee_proportional_millionths: 0,
4335 excess_data: Vec::new()
4337 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4338 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4339 short_channel_id: 13,
4342 cltv_expiry_delta: 0,
4343 htlc_minimum_msat: 0,
4344 htlc_maximum_msat: 100_000,
4346 fee_proportional_millionths: 0,
4347 excess_data: Vec::new()
4350 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4351 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4352 short_channel_id: 6,
4355 cltv_expiry_delta: 0,
4356 htlc_minimum_msat: 0,
4357 htlc_maximum_msat: 50_000,
4359 fee_proportional_millionths: 0,
4360 excess_data: Vec::new()
4362 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4363 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4364 short_channel_id: 11,
4367 cltv_expiry_delta: 0,
4368 htlc_minimum_msat: 0,
4369 htlc_maximum_msat: 100_000,
4371 fee_proportional_millionths: 0,
4372 excess_data: Vec::new()
4375 // Attempt to route more than available results in a failure.
4376 let route_params = RouteParameters::from_payment_params_and_value(
4377 payment_params.clone(), 60_000);
4378 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4379 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4380 &scorer, &(), &random_seed_bytes) {
4381 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4382 } else { panic!(); }
4386 // Now, attempt to route 49 sats (just a bit below the capacity).
4387 let route_params = RouteParameters::from_payment_params_and_value(
4388 payment_params.clone(), 49_000);
4389 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4390 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4391 assert_eq!(route.paths.len(), 1);
4392 let mut total_amount_paid_msat = 0;
4393 for path in &route.paths {
4394 assert_eq!(path.hops.len(), 4);
4395 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4396 total_amount_paid_msat += path.final_value_msat();
4398 assert_eq!(total_amount_paid_msat, 49_000);
4402 // Attempt to route an exact amount is also fine
4403 let route_params = RouteParameters::from_payment_params_and_value(
4404 payment_params, 50_000);
4405 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4406 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4407 assert_eq!(route.paths.len(), 1);
4408 let mut total_amount_paid_msat = 0;
4409 for path in &route.paths {
4410 assert_eq!(path.hops.len(), 4);
4411 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4412 total_amount_paid_msat += path.final_value_msat();
4414 assert_eq!(total_amount_paid_msat, 50_000);
4419 fn ignore_fee_first_hop_test() {
4420 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4421 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4422 let scorer = ln_test_utils::TestScorer::new();
4423 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4424 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4425 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4427 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4428 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4429 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4430 short_channel_id: 1,
4433 cltv_expiry_delta: 0,
4434 htlc_minimum_msat: 0,
4435 htlc_maximum_msat: 100_000,
4436 fee_base_msat: 1_000_000,
4437 fee_proportional_millionths: 0,
4438 excess_data: Vec::new()
4440 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4441 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4442 short_channel_id: 3,
4445 cltv_expiry_delta: 0,
4446 htlc_minimum_msat: 0,
4447 htlc_maximum_msat: 50_000,
4449 fee_proportional_millionths: 0,
4450 excess_data: Vec::new()
4454 let route_params = RouteParameters::from_payment_params_and_value(
4455 payment_params, 50_000);
4456 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4457 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4458 assert_eq!(route.paths.len(), 1);
4459 let mut total_amount_paid_msat = 0;
4460 for path in &route.paths {
4461 assert_eq!(path.hops.len(), 2);
4462 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4463 total_amount_paid_msat += path.final_value_msat();
4465 assert_eq!(total_amount_paid_msat, 50_000);
4470 fn simple_mpp_route_test() {
4471 let (secp_ctx, _, _, _, _) = build_graph();
4472 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4473 let config = UserConfig::default();
4474 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4475 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4476 do_simple_mpp_route_test(clear_payment_params);
4478 // MPP to a 1-hop blinded path for nodes[2]
4479 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4480 let blinded_path = BlindedPath {
4481 introduction_node_id: nodes[2],
4482 blinding_point: ln_test_utils::pubkey(42),
4483 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4485 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4487 fee_proportional_millionths: 0,
4488 htlc_minimum_msat: 0,
4489 htlc_maximum_msat: 0,
4490 cltv_expiry_delta: 0,
4491 features: BlindedHopFeatures::empty(),
4493 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4494 .with_bolt12_features(bolt12_features.clone()).unwrap();
4495 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4497 // MPP to 3 2-hop blinded paths
4498 let mut blinded_path_node_0 = blinded_path.clone();
4499 blinded_path_node_0.introduction_node_id = nodes[0];
4500 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4501 let mut node_0_payinfo = blinded_payinfo.clone();
4502 node_0_payinfo.htlc_maximum_msat = 50_000;
4504 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4505 blinded_path_node_7.introduction_node_id = nodes[7];
4506 let mut node_7_payinfo = blinded_payinfo.clone();
4507 node_7_payinfo.htlc_maximum_msat = 60_000;
4509 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4510 blinded_path_node_1.introduction_node_id = nodes[1];
4511 let mut node_1_payinfo = blinded_payinfo.clone();
4512 node_1_payinfo.htlc_maximum_msat = 180_000;
4514 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4516 (node_0_payinfo, blinded_path_node_0),
4517 (node_7_payinfo, blinded_path_node_7),
4518 (node_1_payinfo, blinded_path_node_1)
4520 .with_bolt12_features(bolt12_features).unwrap();
4521 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4525 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4526 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4527 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4528 let scorer = ln_test_utils::TestScorer::new();
4529 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4530 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4532 // We need a route consisting of 3 paths:
4533 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4534 // To achieve this, the amount being transferred should be around
4535 // the total capacity of these 3 paths.
4537 // First, we set limits on these (previously unlimited) channels.
4538 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4540 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4541 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4542 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4543 short_channel_id: 1,
4546 cltv_expiry_delta: 0,
4547 htlc_minimum_msat: 0,
4548 htlc_maximum_msat: 100_000,
4550 fee_proportional_millionths: 0,
4551 excess_data: Vec::new()
4553 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4554 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4555 short_channel_id: 3,
4558 cltv_expiry_delta: 0,
4559 htlc_minimum_msat: 0,
4560 htlc_maximum_msat: 50_000,
4562 fee_proportional_millionths: 0,
4563 excess_data: Vec::new()
4566 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4567 // (total limit 60).
4568 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4569 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4570 short_channel_id: 12,
4573 cltv_expiry_delta: 0,
4574 htlc_minimum_msat: 0,
4575 htlc_maximum_msat: 60_000,
4577 fee_proportional_millionths: 0,
4578 excess_data: Vec::new()
4580 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4581 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4582 short_channel_id: 13,
4585 cltv_expiry_delta: 0,
4586 htlc_minimum_msat: 0,
4587 htlc_maximum_msat: 60_000,
4589 fee_proportional_millionths: 0,
4590 excess_data: Vec::new()
4593 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4594 // (total capacity 180 sats).
4595 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4596 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4597 short_channel_id: 2,
4600 cltv_expiry_delta: 0,
4601 htlc_minimum_msat: 0,
4602 htlc_maximum_msat: 200_000,
4604 fee_proportional_millionths: 0,
4605 excess_data: Vec::new()
4607 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4608 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4609 short_channel_id: 4,
4612 cltv_expiry_delta: 0,
4613 htlc_minimum_msat: 0,
4614 htlc_maximum_msat: 180_000,
4616 fee_proportional_millionths: 0,
4617 excess_data: Vec::new()
4621 // Attempt to route more than available results in a failure.
4622 let route_params = RouteParameters::from_payment_params_and_value(
4623 payment_params.clone(), 300_000);
4624 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4625 &our_id, &route_params, &network_graph.read_only(), None,
4626 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4627 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4628 } else { panic!(); }
4632 // Attempt to route while setting max_path_count to 0 results in a failure.
4633 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4634 let route_params = RouteParameters::from_payment_params_and_value(
4635 zero_payment_params, 100);
4636 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4637 &our_id, &route_params, &network_graph.read_only(), None,
4638 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4639 assert_eq!(err, "Can't find a route with no paths allowed.");
4640 } else { panic!(); }
4644 // Attempt to route while setting max_path_count to 3 results in a failure.
4645 // This is the case because the minimal_value_contribution_msat would require each path
4646 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4647 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4648 let route_params = RouteParameters::from_payment_params_and_value(
4649 fail_payment_params, 250_000);
4650 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4651 &our_id, &route_params, &network_graph.read_only(), None,
4652 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4653 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4654 } else { panic!(); }
4658 // Now, attempt to route 250 sats (just a bit below the capacity).
4659 // Our algorithm should provide us with these 3 paths.
4660 let route_params = RouteParameters::from_payment_params_and_value(
4661 payment_params.clone(), 250_000);
4662 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4663 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4664 assert_eq!(route.paths.len(), 3);
4665 let mut total_amount_paid_msat = 0;
4666 for path in &route.paths {
4667 if let Some(bt) = &path.blinded_tail {
4668 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4670 assert_eq!(path.hops.len(), 2);
4671 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4673 total_amount_paid_msat += path.final_value_msat();
4675 assert_eq!(total_amount_paid_msat, 250_000);
4679 // Attempt to route an exact amount is also fine
4680 let route_params = RouteParameters::from_payment_params_and_value(
4681 payment_params.clone(), 290_000);
4682 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4683 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4684 assert_eq!(route.paths.len(), 3);
4685 let mut total_amount_paid_msat = 0;
4686 for path in &route.paths {
4687 if payment_params.payee.blinded_route_hints().len() != 0 {
4688 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4689 if let Some(bt) = &path.blinded_tail {
4690 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4691 if bt.hops.len() > 1 {
4692 assert_eq!(path.hops.last().unwrap().pubkey,
4693 payment_params.payee.blinded_route_hints().iter()
4694 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4695 .map(|(_, p)| p.introduction_node_id).unwrap());
4697 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4700 assert_eq!(path.hops.len(), 2);
4701 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4703 total_amount_paid_msat += path.final_value_msat();
4705 assert_eq!(total_amount_paid_msat, 290_000);
4710 fn long_mpp_route_test() {
4711 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4712 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4713 let scorer = ln_test_utils::TestScorer::new();
4714 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4715 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4716 let config = UserConfig::default();
4717 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4718 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4720 // We need a route consisting of 3 paths:
4721 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4722 // Note that these paths overlap (channels 5, 12, 13).
4723 // We will route 300 sats.
4724 // Each path will have 100 sats capacity, those channels which
4725 // are used twice will have 200 sats capacity.
4727 // Disable other potential paths.
4728 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4729 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4730 short_channel_id: 2,
4733 cltv_expiry_delta: 0,
4734 htlc_minimum_msat: 0,
4735 htlc_maximum_msat: 100_000,
4737 fee_proportional_millionths: 0,
4738 excess_data: Vec::new()
4740 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4741 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4742 short_channel_id: 7,
4745 cltv_expiry_delta: 0,
4746 htlc_minimum_msat: 0,
4747 htlc_maximum_msat: 100_000,
4749 fee_proportional_millionths: 0,
4750 excess_data: Vec::new()
4753 // Path via {node0, node2} is channels {1, 3, 5}.
4754 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4755 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4756 short_channel_id: 1,
4759 cltv_expiry_delta: 0,
4760 htlc_minimum_msat: 0,
4761 htlc_maximum_msat: 100_000,
4763 fee_proportional_millionths: 0,
4764 excess_data: Vec::new()
4766 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4767 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4768 short_channel_id: 3,
4771 cltv_expiry_delta: 0,
4772 htlc_minimum_msat: 0,
4773 htlc_maximum_msat: 100_000,
4775 fee_proportional_millionths: 0,
4776 excess_data: Vec::new()
4779 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4780 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4781 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4782 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4783 short_channel_id: 5,
4786 cltv_expiry_delta: 0,
4787 htlc_minimum_msat: 0,
4788 htlc_maximum_msat: 200_000,
4790 fee_proportional_millionths: 0,
4791 excess_data: Vec::new()
4794 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4795 // Add 100 sats to the capacities of {12, 13}, because these channels
4796 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4797 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4798 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4799 short_channel_id: 12,
4802 cltv_expiry_delta: 0,
4803 htlc_minimum_msat: 0,
4804 htlc_maximum_msat: 200_000,
4806 fee_proportional_millionths: 0,
4807 excess_data: Vec::new()
4809 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4810 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4811 short_channel_id: 13,
4814 cltv_expiry_delta: 0,
4815 htlc_minimum_msat: 0,
4816 htlc_maximum_msat: 200_000,
4818 fee_proportional_millionths: 0,
4819 excess_data: Vec::new()
4822 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4824 short_channel_id: 6,
4827 cltv_expiry_delta: 0,
4828 htlc_minimum_msat: 0,
4829 htlc_maximum_msat: 100_000,
4831 fee_proportional_millionths: 0,
4832 excess_data: Vec::new()
4834 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4836 short_channel_id: 11,
4839 cltv_expiry_delta: 0,
4840 htlc_minimum_msat: 0,
4841 htlc_maximum_msat: 100_000,
4843 fee_proportional_millionths: 0,
4844 excess_data: Vec::new()
4847 // Path via {node7, node2} is channels {12, 13, 5}.
4848 // We already limited them to 200 sats (they are used twice for 100 sats).
4849 // Nothing to do here.
4852 // Attempt to route more than available results in a failure.
4853 let route_params = RouteParameters::from_payment_params_and_value(
4854 payment_params.clone(), 350_000);
4855 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4856 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4857 &scorer, &(), &random_seed_bytes) {
4858 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4859 } else { panic!(); }
4863 // Now, attempt to route 300 sats (exact amount we can route).
4864 // Our algorithm should provide us with these 3 paths, 100 sats each.
4865 let route_params = RouteParameters::from_payment_params_and_value(
4866 payment_params, 300_000);
4867 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4868 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4869 assert_eq!(route.paths.len(), 3);
4871 let mut total_amount_paid_msat = 0;
4872 for path in &route.paths {
4873 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4874 total_amount_paid_msat += path.final_value_msat();
4876 assert_eq!(total_amount_paid_msat, 300_000);
4882 fn mpp_cheaper_route_test() {
4883 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4884 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4885 let scorer = ln_test_utils::TestScorer::new();
4886 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4887 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4888 let config = UserConfig::default();
4889 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4891 // This test checks that if we have two cheaper paths and one more expensive path,
4892 // so that liquidity-wise any 2 of 3 combination is sufficient,
4893 // two cheaper paths will be taken.
4894 // These paths have equal available liquidity.
4896 // We need a combination of 3 paths:
4897 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4898 // Note that these paths overlap (channels 5, 12, 13).
4899 // Each path will have 100 sats capacity, those channels which
4900 // are used twice will have 200 sats capacity.
4902 // Disable other potential paths.
4903 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4904 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4905 short_channel_id: 2,
4908 cltv_expiry_delta: 0,
4909 htlc_minimum_msat: 0,
4910 htlc_maximum_msat: 100_000,
4912 fee_proportional_millionths: 0,
4913 excess_data: Vec::new()
4915 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4916 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4917 short_channel_id: 7,
4920 cltv_expiry_delta: 0,
4921 htlc_minimum_msat: 0,
4922 htlc_maximum_msat: 100_000,
4924 fee_proportional_millionths: 0,
4925 excess_data: Vec::new()
4928 // Path via {node0, node2} is channels {1, 3, 5}.
4929 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4930 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4931 short_channel_id: 1,
4934 cltv_expiry_delta: 0,
4935 htlc_minimum_msat: 0,
4936 htlc_maximum_msat: 100_000,
4938 fee_proportional_millionths: 0,
4939 excess_data: Vec::new()
4941 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4942 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4943 short_channel_id: 3,
4946 cltv_expiry_delta: 0,
4947 htlc_minimum_msat: 0,
4948 htlc_maximum_msat: 100_000,
4950 fee_proportional_millionths: 0,
4951 excess_data: Vec::new()
4954 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4955 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4956 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4957 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4958 short_channel_id: 5,
4961 cltv_expiry_delta: 0,
4962 htlc_minimum_msat: 0,
4963 htlc_maximum_msat: 200_000,
4965 fee_proportional_millionths: 0,
4966 excess_data: Vec::new()
4969 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4970 // Add 100 sats to the capacities of {12, 13}, because these channels
4971 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4972 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4974 short_channel_id: 12,
4977 cltv_expiry_delta: 0,
4978 htlc_minimum_msat: 0,
4979 htlc_maximum_msat: 200_000,
4981 fee_proportional_millionths: 0,
4982 excess_data: Vec::new()
4984 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4985 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4986 short_channel_id: 13,
4989 cltv_expiry_delta: 0,
4990 htlc_minimum_msat: 0,
4991 htlc_maximum_msat: 200_000,
4993 fee_proportional_millionths: 0,
4994 excess_data: Vec::new()
4997 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4998 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4999 short_channel_id: 6,
5002 cltv_expiry_delta: 0,
5003 htlc_minimum_msat: 0,
5004 htlc_maximum_msat: 100_000,
5005 fee_base_msat: 1_000,
5006 fee_proportional_millionths: 0,
5007 excess_data: Vec::new()
5009 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5010 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5011 short_channel_id: 11,
5014 cltv_expiry_delta: 0,
5015 htlc_minimum_msat: 0,
5016 htlc_maximum_msat: 100_000,
5018 fee_proportional_millionths: 0,
5019 excess_data: Vec::new()
5022 // Path via {node7, node2} is channels {12, 13, 5}.
5023 // We already limited them to 200 sats (they are used twice for 100 sats).
5024 // Nothing to do here.
5027 // Now, attempt to route 180 sats.
5028 // Our algorithm should provide us with these 2 paths.
5029 let route_params = RouteParameters::from_payment_params_and_value(
5030 payment_params, 180_000);
5031 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5032 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5033 assert_eq!(route.paths.len(), 2);
5035 let mut total_value_transferred_msat = 0;
5036 let mut total_paid_msat = 0;
5037 for path in &route.paths {
5038 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5039 total_value_transferred_msat += path.final_value_msat();
5040 for hop in &path.hops {
5041 total_paid_msat += hop.fee_msat;
5044 // If we paid fee, this would be higher.
5045 assert_eq!(total_value_transferred_msat, 180_000);
5046 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5047 assert_eq!(total_fees_paid, 0);
5052 fn fees_on_mpp_route_test() {
5053 // This test makes sure that MPP algorithm properly takes into account
5054 // fees charged on the channels, by making the fees impactful:
5055 // if the fee is not properly accounted for, the behavior is different.
5056 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5057 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5058 let scorer = ln_test_utils::TestScorer::new();
5059 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5060 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5061 let config = UserConfig::default();
5062 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5064 // We need a route consisting of 2 paths:
5065 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5066 // We will route 200 sats, Each path will have 100 sats capacity.
5068 // This test is not particularly stable: e.g.,
5069 // there's a way to route via {node0, node2, node4}.
5070 // It works while pathfinding is deterministic, but can be broken otherwise.
5071 // It's fine to ignore this concern for now.
5073 // Disable other potential paths.
5074 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5075 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5076 short_channel_id: 2,
5079 cltv_expiry_delta: 0,
5080 htlc_minimum_msat: 0,
5081 htlc_maximum_msat: 100_000,
5083 fee_proportional_millionths: 0,
5084 excess_data: Vec::new()
5087 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5088 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5089 short_channel_id: 7,
5092 cltv_expiry_delta: 0,
5093 htlc_minimum_msat: 0,
5094 htlc_maximum_msat: 100_000,
5096 fee_proportional_millionths: 0,
5097 excess_data: Vec::new()
5100 // Path via {node0, node2} is channels {1, 3, 5}.
5101 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5102 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5103 short_channel_id: 1,
5106 cltv_expiry_delta: 0,
5107 htlc_minimum_msat: 0,
5108 htlc_maximum_msat: 100_000,
5110 fee_proportional_millionths: 0,
5111 excess_data: Vec::new()
5113 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5114 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5115 short_channel_id: 3,
5118 cltv_expiry_delta: 0,
5119 htlc_minimum_msat: 0,
5120 htlc_maximum_msat: 100_000,
5122 fee_proportional_millionths: 0,
5123 excess_data: Vec::new()
5126 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5127 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5128 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5129 short_channel_id: 5,
5132 cltv_expiry_delta: 0,
5133 htlc_minimum_msat: 0,
5134 htlc_maximum_msat: 100_000,
5136 fee_proportional_millionths: 0,
5137 excess_data: Vec::new()
5140 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5141 // All channels should be 100 sats capacity. But for the fee experiment,
5142 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5143 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5144 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5145 // so no matter how large are other channels,
5146 // the whole path will be limited by 100 sats with just these 2 conditions:
5147 // - channel 12 capacity is 250 sats
5148 // - fee for channel 6 is 150 sats
5149 // Let's test this by enforcing these 2 conditions and removing other limits.
5150 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5151 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5152 short_channel_id: 12,
5155 cltv_expiry_delta: 0,
5156 htlc_minimum_msat: 0,
5157 htlc_maximum_msat: 250_000,
5159 fee_proportional_millionths: 0,
5160 excess_data: Vec::new()
5162 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5163 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5164 short_channel_id: 13,
5167 cltv_expiry_delta: 0,
5168 htlc_minimum_msat: 0,
5169 htlc_maximum_msat: MAX_VALUE_MSAT,
5171 fee_proportional_millionths: 0,
5172 excess_data: Vec::new()
5175 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5176 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5177 short_channel_id: 6,
5180 cltv_expiry_delta: 0,
5181 htlc_minimum_msat: 0,
5182 htlc_maximum_msat: MAX_VALUE_MSAT,
5183 fee_base_msat: 150_000,
5184 fee_proportional_millionths: 0,
5185 excess_data: Vec::new()
5187 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5188 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5189 short_channel_id: 11,
5192 cltv_expiry_delta: 0,
5193 htlc_minimum_msat: 0,
5194 htlc_maximum_msat: MAX_VALUE_MSAT,
5196 fee_proportional_millionths: 0,
5197 excess_data: Vec::new()
5201 // Attempt to route more than available results in a failure.
5202 let route_params = RouteParameters::from_payment_params_and_value(
5203 payment_params.clone(), 210_000);
5204 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5205 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5206 &scorer, &(), &random_seed_bytes) {
5207 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5208 } else { panic!(); }
5212 // Now, attempt to route 200 sats (exact amount we can route).
5213 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 200_000);
5214 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5215 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5216 assert_eq!(route.paths.len(), 2);
5218 let mut total_amount_paid_msat = 0;
5219 for path in &route.paths {
5220 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5221 total_amount_paid_msat += path.final_value_msat();
5223 assert_eq!(total_amount_paid_msat, 200_000);
5224 assert_eq!(route.get_total_fees(), 150_000);
5229 fn mpp_with_last_hops() {
5230 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5231 // via a single last-hop route hint, we'd fail to route if we first collected routes
5232 // totaling close but not quite enough to fund the full payment.
5234 // This was because we considered last-hop hints to have exactly the sought payment amount
5235 // instead of the amount we were trying to collect, needlessly limiting our path searching
5236 // at the very first hop.
5238 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5239 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5240 // to only have the remaining to-collect amount in available liquidity.
5242 // This bug appeared in production in some specific channel configurations.
5243 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5244 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5245 let scorer = ln_test_utils::TestScorer::new();
5246 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5247 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5248 let config = UserConfig::default();
5249 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5250 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5251 src_node_id: nodes[2],
5252 short_channel_id: 42,
5253 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5254 cltv_expiry_delta: 42,
5255 htlc_minimum_msat: None,
5256 htlc_maximum_msat: None,
5257 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5259 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5260 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5261 // would first use the no-fee route and then fail to find a path along the second route as
5262 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5263 // under 5% of our payment amount.
5264 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5265 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5266 short_channel_id: 1,
5269 cltv_expiry_delta: (5 << 4) | 5,
5270 htlc_minimum_msat: 0,
5271 htlc_maximum_msat: 99_000,
5272 fee_base_msat: u32::max_value(),
5273 fee_proportional_millionths: u32::max_value(),
5274 excess_data: Vec::new()
5276 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5277 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5278 short_channel_id: 2,
5281 cltv_expiry_delta: (5 << 4) | 3,
5282 htlc_minimum_msat: 0,
5283 htlc_maximum_msat: 99_000,
5284 fee_base_msat: u32::max_value(),
5285 fee_proportional_millionths: u32::max_value(),
5286 excess_data: Vec::new()
5288 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5289 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5290 short_channel_id: 4,
5293 cltv_expiry_delta: (4 << 4) | 1,
5294 htlc_minimum_msat: 0,
5295 htlc_maximum_msat: MAX_VALUE_MSAT,
5297 fee_proportional_millionths: 0,
5298 excess_data: Vec::new()
5300 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5301 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5302 short_channel_id: 13,
5304 flags: 0|2, // Channel disabled
5305 cltv_expiry_delta: (13 << 4) | 1,
5306 htlc_minimum_msat: 0,
5307 htlc_maximum_msat: MAX_VALUE_MSAT,
5309 fee_proportional_millionths: 2000000,
5310 excess_data: Vec::new()
5313 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5315 let route_params = RouteParameters::from_payment_params_and_value(
5316 payment_params, 100_000);
5317 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5318 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5319 assert_eq!(route.paths.len(), 2);
5320 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5321 // Paths are manually ordered ordered by SCID, so:
5322 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5323 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5324 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5325 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5326 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5327 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5328 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5329 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5330 assert_eq!(route.get_total_fees(), 1);
5331 assert_eq!(route.get_total_amount(), 100_000);
5335 fn drop_lowest_channel_mpp_route_test() {
5336 // This test checks that low-capacity channel is dropped when after
5337 // path finding we realize that we found more capacity than we need.
5338 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5339 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5340 let scorer = ln_test_utils::TestScorer::new();
5341 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5342 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5343 let config = UserConfig::default();
5344 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5345 .with_max_channel_saturation_power_of_half(0);
5347 // We need a route consisting of 3 paths:
5348 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5350 // The first and the second paths should be sufficient, but the third should be
5351 // cheaper, so that we select it but drop later.
5353 // First, we set limits on these (previously unlimited) channels.
5354 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5356 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5357 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5358 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5359 short_channel_id: 1,
5362 cltv_expiry_delta: 0,
5363 htlc_minimum_msat: 0,
5364 htlc_maximum_msat: 100_000,
5366 fee_proportional_millionths: 0,
5367 excess_data: Vec::new()
5369 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5370 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5371 short_channel_id: 3,
5374 cltv_expiry_delta: 0,
5375 htlc_minimum_msat: 0,
5376 htlc_maximum_msat: 50_000,
5378 fee_proportional_millionths: 0,
5379 excess_data: Vec::new()
5382 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5383 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5384 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5385 short_channel_id: 12,
5388 cltv_expiry_delta: 0,
5389 htlc_minimum_msat: 0,
5390 htlc_maximum_msat: 60_000,
5392 fee_proportional_millionths: 0,
5393 excess_data: Vec::new()
5395 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5396 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5397 short_channel_id: 13,
5400 cltv_expiry_delta: 0,
5401 htlc_minimum_msat: 0,
5402 htlc_maximum_msat: 60_000,
5404 fee_proportional_millionths: 0,
5405 excess_data: Vec::new()
5408 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5409 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5410 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5411 short_channel_id: 2,
5414 cltv_expiry_delta: 0,
5415 htlc_minimum_msat: 0,
5416 htlc_maximum_msat: 20_000,
5418 fee_proportional_millionths: 0,
5419 excess_data: Vec::new()
5421 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5422 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5423 short_channel_id: 4,
5426 cltv_expiry_delta: 0,
5427 htlc_minimum_msat: 0,
5428 htlc_maximum_msat: 20_000,
5430 fee_proportional_millionths: 0,
5431 excess_data: Vec::new()
5435 // Attempt to route more than available results in a failure.
5436 let route_params = RouteParameters::from_payment_params_and_value(
5437 payment_params.clone(), 150_000);
5438 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5439 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5440 &scorer, &(), &random_seed_bytes) {
5441 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5442 } else { panic!(); }
5446 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5447 // Our algorithm should provide us with these 3 paths.
5448 let route_params = RouteParameters::from_payment_params_and_value(
5449 payment_params.clone(), 125_000);
5450 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5451 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5452 assert_eq!(route.paths.len(), 3);
5453 let mut total_amount_paid_msat = 0;
5454 for path in &route.paths {
5455 assert_eq!(path.hops.len(), 2);
5456 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5457 total_amount_paid_msat += path.final_value_msat();
5459 assert_eq!(total_amount_paid_msat, 125_000);
5463 // Attempt to route without the last small cheap channel
5464 let route_params = RouteParameters::from_payment_params_and_value(
5465 payment_params, 90_000);
5466 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5467 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5468 assert_eq!(route.paths.len(), 2);
5469 let mut total_amount_paid_msat = 0;
5470 for path in &route.paths {
5471 assert_eq!(path.hops.len(), 2);
5472 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5473 total_amount_paid_msat += path.final_value_msat();
5475 assert_eq!(total_amount_paid_msat, 90_000);
5480 fn min_criteria_consistency() {
5481 // Test that we don't use an inconsistent metric between updating and walking nodes during
5482 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5483 // was updated with a different criterion from the heap sorting, resulting in loops in
5484 // calculated paths. We test for that specific case here.
5486 // We construct a network that looks like this:
5488 // node2 -1(3)2- node3
5492 // node1 -1(5)2- node4 -1(1)2- node6
5498 // We create a loop on the side of our real path - our destination is node 6, with a
5499 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5500 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5501 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5502 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5503 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5504 // "previous hop" being set to node 3, creating a loop in the path.
5505 let secp_ctx = Secp256k1::new();
5506 let logger = Arc::new(ln_test_utils::TestLogger::new());
5507 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5508 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5509 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5510 let scorer = ln_test_utils::TestScorer::new();
5511 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5512 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5513 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5515 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5516 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5517 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5518 short_channel_id: 6,
5521 cltv_expiry_delta: (6 << 4) | 0,
5522 htlc_minimum_msat: 0,
5523 htlc_maximum_msat: MAX_VALUE_MSAT,
5525 fee_proportional_millionths: 0,
5526 excess_data: Vec::new()
5528 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5530 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5531 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5532 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5533 short_channel_id: 5,
5536 cltv_expiry_delta: (5 << 4) | 0,
5537 htlc_minimum_msat: 0,
5538 htlc_maximum_msat: MAX_VALUE_MSAT,
5540 fee_proportional_millionths: 0,
5541 excess_data: Vec::new()
5543 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5545 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5546 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5547 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5548 short_channel_id: 4,
5551 cltv_expiry_delta: (4 << 4) | 0,
5552 htlc_minimum_msat: 0,
5553 htlc_maximum_msat: MAX_VALUE_MSAT,
5555 fee_proportional_millionths: 0,
5556 excess_data: Vec::new()
5558 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5560 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5561 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5562 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5563 short_channel_id: 3,
5566 cltv_expiry_delta: (3 << 4) | 0,
5567 htlc_minimum_msat: 0,
5568 htlc_maximum_msat: MAX_VALUE_MSAT,
5570 fee_proportional_millionths: 0,
5571 excess_data: Vec::new()
5573 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5575 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5576 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5577 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5578 short_channel_id: 2,
5581 cltv_expiry_delta: (2 << 4) | 0,
5582 htlc_minimum_msat: 0,
5583 htlc_maximum_msat: MAX_VALUE_MSAT,
5585 fee_proportional_millionths: 0,
5586 excess_data: Vec::new()
5589 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5590 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5591 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5592 short_channel_id: 1,
5595 cltv_expiry_delta: (1 << 4) | 0,
5596 htlc_minimum_msat: 100,
5597 htlc_maximum_msat: MAX_VALUE_MSAT,
5599 fee_proportional_millionths: 0,
5600 excess_data: Vec::new()
5602 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5605 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5606 let route_params = RouteParameters::from_payment_params_and_value(
5607 payment_params, 10_000);
5608 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5609 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5610 assert_eq!(route.paths.len(), 1);
5611 assert_eq!(route.paths[0].hops.len(), 3);
5613 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5614 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5615 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5616 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5617 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5618 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5620 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5621 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5622 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5623 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5624 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5625 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5627 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5628 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5629 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5630 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5631 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5632 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5638 fn exact_fee_liquidity_limit() {
5639 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5640 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5641 // we calculated fees on a higher value, resulting in us ignoring such paths.
5642 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5643 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5644 let scorer = ln_test_utils::TestScorer::new();
5645 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5646 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5647 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5649 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5651 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5652 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5653 short_channel_id: 2,
5656 cltv_expiry_delta: 0,
5657 htlc_minimum_msat: 0,
5658 htlc_maximum_msat: 85_000,
5660 fee_proportional_millionths: 0,
5661 excess_data: Vec::new()
5664 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5665 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5666 short_channel_id: 12,
5669 cltv_expiry_delta: (4 << 4) | 1,
5670 htlc_minimum_msat: 0,
5671 htlc_maximum_msat: 270_000,
5673 fee_proportional_millionths: 1000000,
5674 excess_data: Vec::new()
5678 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5679 // 200% fee charged channel 13 in the 1-to-2 direction.
5680 let route_params = RouteParameters::from_payment_params_and_value(
5681 payment_params, 90_000);
5682 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5683 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5684 assert_eq!(route.paths.len(), 1);
5685 assert_eq!(route.paths[0].hops.len(), 2);
5687 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5688 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5689 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5690 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5691 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5692 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5694 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5695 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5696 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5697 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5698 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5699 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5704 fn htlc_max_reduction_below_min() {
5705 // Test that if, while walking the graph, we reduce the value being sent to meet an
5706 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5707 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5708 // resulting in us thinking there is no possible path, even if other paths exist.
5709 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5710 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5711 let scorer = ln_test_utils::TestScorer::new();
5712 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5713 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5714 let config = UserConfig::default();
5715 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5717 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5718 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5719 // then try to send 90_000.
5720 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5721 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5722 short_channel_id: 2,
5725 cltv_expiry_delta: 0,
5726 htlc_minimum_msat: 0,
5727 htlc_maximum_msat: 80_000,
5729 fee_proportional_millionths: 0,
5730 excess_data: Vec::new()
5732 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5733 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5734 short_channel_id: 4,
5737 cltv_expiry_delta: (4 << 4) | 1,
5738 htlc_minimum_msat: 90_000,
5739 htlc_maximum_msat: MAX_VALUE_MSAT,
5741 fee_proportional_millionths: 0,
5742 excess_data: Vec::new()
5746 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5747 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5748 // expensive) channels 12-13 path.
5749 let route_params = RouteParameters::from_payment_params_and_value(
5750 payment_params, 90_000);
5751 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5752 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5753 assert_eq!(route.paths.len(), 1);
5754 assert_eq!(route.paths[0].hops.len(), 2);
5756 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5757 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5758 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5759 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5760 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5761 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5763 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5764 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5765 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5766 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5767 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5768 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5773 fn multiple_direct_first_hops() {
5774 // Previously we'd only ever considered one first hop path per counterparty.
5775 // However, as we don't restrict users to one channel per peer, we really need to support
5776 // looking at all first hop paths.
5777 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5778 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5779 // route over multiple channels with the same first hop.
5780 let secp_ctx = Secp256k1::new();
5781 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5782 let logger = Arc::new(ln_test_utils::TestLogger::new());
5783 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5784 let scorer = ln_test_utils::TestScorer::new();
5785 let config = UserConfig::default();
5786 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5787 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5788 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5791 let route_params = RouteParameters::from_payment_params_and_value(
5792 payment_params.clone(), 100_000);
5793 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5794 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5795 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5796 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5797 assert_eq!(route.paths.len(), 1);
5798 assert_eq!(route.paths[0].hops.len(), 1);
5800 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5801 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5802 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5805 let route_params = RouteParameters::from_payment_params_and_value(
5806 payment_params.clone(), 100_000);
5807 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5808 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5809 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5810 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5811 assert_eq!(route.paths.len(), 2);
5812 assert_eq!(route.paths[0].hops.len(), 1);
5813 assert_eq!(route.paths[1].hops.len(), 1);
5815 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5816 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5818 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5819 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5821 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5822 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5826 // If we have a bunch of outbound channels to the same node, where most are not
5827 // sufficient to pay the full payment, but one is, we should default to just using the
5828 // one single channel that has sufficient balance, avoiding MPP.
5830 // If we have several options above the 3xpayment value threshold, we should pick the
5831 // smallest of them, avoiding further fragmenting our available outbound balance to
5833 let route_params = RouteParameters::from_payment_params_and_value(
5834 payment_params, 100_000);
5835 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5836 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5837 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5838 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5839 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5840 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5841 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5842 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5843 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5844 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5845 assert_eq!(route.paths.len(), 1);
5846 assert_eq!(route.paths[0].hops.len(), 1);
5848 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5849 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5850 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5855 fn prefers_shorter_route_with_higher_fees() {
5856 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5857 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5858 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5860 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5861 let scorer = ln_test_utils::TestScorer::new();
5862 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5863 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5864 let route_params = RouteParameters::from_payment_params_and_value(
5865 payment_params.clone(), 100);
5866 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5867 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5868 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5870 assert_eq!(route.get_total_fees(), 100);
5871 assert_eq!(route.get_total_amount(), 100);
5872 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5874 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5875 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5876 let scorer = FixedPenaltyScorer::with_penalty(100);
5877 let route_params = RouteParameters::from_payment_params_and_value(
5878 payment_params, 100);
5879 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5880 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5881 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5883 assert_eq!(route.get_total_fees(), 300);
5884 assert_eq!(route.get_total_amount(), 100);
5885 assert_eq!(path, vec![2, 4, 7, 10]);
5888 struct BadChannelScorer {
5889 short_channel_id: u64,
5893 impl Writeable for BadChannelScorer {
5894 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5896 impl ScoreLookUp for BadChannelScorer {
5897 type ScoreParams = ();
5898 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5899 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5903 struct BadNodeScorer {
5908 impl Writeable for BadNodeScorer {
5909 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5912 impl ScoreLookUp for BadNodeScorer {
5913 type ScoreParams = ();
5914 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5915 if *target == self.node_id { u64::max_value() } else { 0 }
5920 fn avoids_routing_through_bad_channels_and_nodes() {
5921 let (secp_ctx, network, _, _, logger) = build_graph();
5922 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5923 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5924 let network_graph = network.read_only();
5926 // A path to nodes[6] exists when no penalties are applied to any channel.
5927 let scorer = ln_test_utils::TestScorer::new();
5928 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5929 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5930 let route_params = RouteParameters::from_payment_params_and_value(
5931 payment_params, 100);
5932 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5933 &scorer, &(), &random_seed_bytes).unwrap();
5934 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5936 assert_eq!(route.get_total_fees(), 100);
5937 assert_eq!(route.get_total_amount(), 100);
5938 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5940 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5941 let scorer = BadChannelScorer { short_channel_id: 6 };
5942 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5943 &scorer, &(), &random_seed_bytes).unwrap();
5944 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5946 assert_eq!(route.get_total_fees(), 300);
5947 assert_eq!(route.get_total_amount(), 100);
5948 assert_eq!(path, vec![2, 4, 7, 10]);
5950 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5951 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5952 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5953 &scorer, &(), &random_seed_bytes) {
5954 Err(LightningError { err, .. } ) => {
5955 assert_eq!(err, "Failed to find a path to the given destination");
5957 Ok(_) => panic!("Expected error"),
5962 fn total_fees_single_path() {
5964 paths: vec![Path { hops: vec![
5966 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5967 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5968 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5971 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5972 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5973 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5976 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5977 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5978 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5980 ], blinded_tail: None }],
5984 assert_eq!(route.get_total_fees(), 250);
5985 assert_eq!(route.get_total_amount(), 225);
5989 fn total_fees_multi_path() {
5991 paths: vec![Path { hops: vec![
5993 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5994 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5995 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5998 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5999 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6000 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
6002 ], blinded_tail: None }, Path { hops: vec![
6004 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6005 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6006 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
6009 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6010 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6011 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
6013 ], blinded_tail: None }],
6017 assert_eq!(route.get_total_fees(), 200);
6018 assert_eq!(route.get_total_amount(), 300);
6022 fn total_empty_route_no_panic() {
6023 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6024 // would both panic if the route was completely empty. We test to ensure they return 0
6025 // here, even though its somewhat nonsensical as a route.
6026 let route = Route { paths: Vec::new(), route_params: None };
6028 assert_eq!(route.get_total_fees(), 0);
6029 assert_eq!(route.get_total_amount(), 0);
6033 fn limits_total_cltv_delta() {
6034 let (secp_ctx, network, _, _, logger) = build_graph();
6035 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6036 let network_graph = network.read_only();
6038 let scorer = ln_test_utils::TestScorer::new();
6040 // Make sure that generally there is at least one route available
6041 let feasible_max_total_cltv_delta = 1008;
6042 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6043 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6044 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6045 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6046 let route_params = RouteParameters::from_payment_params_and_value(
6047 feasible_payment_params, 100);
6048 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6049 &scorer, &(), &random_seed_bytes).unwrap();
6050 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6051 assert_ne!(path.len(), 0);
6053 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6054 let fail_max_total_cltv_delta = 23;
6055 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6056 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6057 let route_params = RouteParameters::from_payment_params_and_value(
6058 fail_payment_params, 100);
6059 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6060 &(), &random_seed_bytes)
6062 Err(LightningError { err, .. } ) => {
6063 assert_eq!(err, "Failed to find a path to the given destination");
6065 Ok(_) => panic!("Expected error"),
6070 fn avoids_recently_failed_paths() {
6071 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6072 // randomly inserting channels into it until we can't find a route anymore.
6073 let (secp_ctx, network, _, _, logger) = build_graph();
6074 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6075 let network_graph = network.read_only();
6077 let scorer = ln_test_utils::TestScorer::new();
6078 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6079 .with_max_path_count(1);
6080 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6081 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6083 // We should be able to find a route initially, and then after we fail a few random
6084 // channels eventually we won't be able to any longer.
6085 let route_params = RouteParameters::from_payment_params_and_value(
6086 payment_params.clone(), 100);
6087 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6088 &scorer, &(), &random_seed_bytes).is_ok());
6090 let route_params = RouteParameters::from_payment_params_and_value(
6091 payment_params.clone(), 100);
6092 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6093 Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
6095 for chan in route.paths[0].hops.iter() {
6096 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6098 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6099 % route.paths[0].hops.len();
6100 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6106 fn limits_path_length() {
6107 let (secp_ctx, network, _, _, logger) = build_line_graph();
6108 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6109 let network_graph = network.read_only();
6111 let scorer = ln_test_utils::TestScorer::new();
6112 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6113 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6115 // First check we can actually create a long route on this graph.
6116 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6117 let route_params = RouteParameters::from_payment_params_and_value(
6118 feasible_payment_params, 100);
6119 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6120 &scorer, &(), &random_seed_bytes).unwrap();
6121 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6122 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6124 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6125 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6126 let route_params = RouteParameters::from_payment_params_and_value(
6127 fail_payment_params, 100);
6128 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6129 &(), &random_seed_bytes)
6131 Err(LightningError { err, .. } ) => {
6132 assert_eq!(err, "Failed to find a path to the given destination");
6134 Ok(_) => panic!("Expected error"),
6139 fn adds_and_limits_cltv_offset() {
6140 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6141 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6143 let scorer = ln_test_utils::TestScorer::new();
6145 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6146 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6147 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6148 let route_params = RouteParameters::from_payment_params_and_value(
6149 payment_params.clone(), 100);
6150 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6151 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6152 assert_eq!(route.paths.len(), 1);
6154 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6156 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6157 let mut route_default = route.clone();
6158 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6159 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6160 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6161 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6162 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6164 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6165 let mut route_limited = route.clone();
6166 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6167 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6168 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6169 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6170 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6174 fn adds_plausible_cltv_offset() {
6175 let (secp_ctx, network, _, _, logger) = build_graph();
6176 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6177 let network_graph = network.read_only();
6178 let network_nodes = network_graph.nodes();
6179 let network_channels = network_graph.channels();
6180 let scorer = ln_test_utils::TestScorer::new();
6181 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6182 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6183 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6185 let route_params = RouteParameters::from_payment_params_and_value(
6186 payment_params.clone(), 100);
6187 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6188 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6189 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6191 let mut path_plausibility = vec![];
6193 for p in route.paths {
6194 // 1. Select random observation point
6195 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6196 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6198 prng.process_in_place(&mut random_bytes);
6199 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6200 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6202 // 2. Calculate what CLTV expiry delta we would observe there
6203 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6205 // 3. Starting from the observation point, find candidate paths
6206 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6207 candidates.push_back((observation_point, vec![]));
6209 let mut found_plausible_candidate = false;
6211 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6212 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6213 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6214 found_plausible_candidate = true;
6215 break 'candidate_loop;
6219 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6220 for channel_id in &cur_node.channels {
6221 if let Some(channel_info) = network_channels.get(&channel_id) {
6222 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6223 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6224 if cur_path_cltv_deltas.iter().sum::<u32>()
6225 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6226 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6227 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6228 candidates.push_back((*next_id, new_path_cltv_deltas));
6236 path_plausibility.push(found_plausible_candidate);
6238 assert!(path_plausibility.iter().all(|x| *x));
6242 fn builds_correct_path_from_hops() {
6243 let (secp_ctx, network, _, _, logger) = build_graph();
6244 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6245 let network_graph = network.read_only();
6247 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6248 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6250 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6251 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6252 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6253 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6254 Arc::clone(&logger), &random_seed_bytes).unwrap();
6255 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6256 assert_eq!(hops.len(), route.paths[0].hops.len());
6257 for (idx, hop_pubkey) in hops.iter().enumerate() {
6258 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6263 fn avoids_saturating_channels() {
6264 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6265 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6266 let decay_params = ProbabilisticScoringDecayParameters::default();
6267 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6269 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6270 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6271 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6272 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6273 short_channel_id: 4,
6276 cltv_expiry_delta: (4 << 4) | 1,
6277 htlc_minimum_msat: 0,
6278 htlc_maximum_msat: 250_000_000,
6280 fee_proportional_millionths: 0,
6281 excess_data: Vec::new()
6283 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6284 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6285 short_channel_id: 13,
6288 cltv_expiry_delta: (13 << 4) | 1,
6289 htlc_minimum_msat: 0,
6290 htlc_maximum_msat: 250_000_000,
6292 fee_proportional_millionths: 0,
6293 excess_data: Vec::new()
6296 let config = UserConfig::default();
6297 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6298 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6299 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6300 // 100,000 sats is less than the available liquidity on each channel, set above.
6301 let route_params = RouteParameters::from_payment_params_and_value(
6302 payment_params, 100_000_000);
6303 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6304 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6305 assert_eq!(route.paths.len(), 2);
6306 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6307 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6310 #[cfg(not(feature = "no-std"))]
6311 pub(super) fn random_init_seed() -> u64 {
6312 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6313 use core::hash::{BuildHasher, Hasher};
6314 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6315 println!("Using seed of {}", seed);
6320 #[cfg(not(feature = "no-std"))]
6321 fn generate_routes() {
6322 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6324 let logger = ln_test_utils::TestLogger::new();
6325 let graph = match super::bench_utils::read_network_graph(&logger) {
6333 let params = ProbabilisticScoringFeeParameters::default();
6334 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6335 let features = super::Bolt11InvoiceFeatures::empty();
6337 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6341 #[cfg(not(feature = "no-std"))]
6342 fn generate_routes_mpp() {
6343 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6345 let logger = ln_test_utils::TestLogger::new();
6346 let graph = match super::bench_utils::read_network_graph(&logger) {
6354 let params = ProbabilisticScoringFeeParameters::default();
6355 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6356 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6358 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6362 #[cfg(not(feature = "no-std"))]
6363 fn generate_large_mpp_routes() {
6364 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6366 let logger = ln_test_utils::TestLogger::new();
6367 let graph = match super::bench_utils::read_network_graph(&logger) {
6375 let params = ProbabilisticScoringFeeParameters::default();
6376 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6377 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6379 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6383 fn honors_manual_penalties() {
6384 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6385 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6387 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6388 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6390 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6391 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6393 // First check set manual penalties are returned by the scorer.
6394 let usage = ChannelUsage {
6396 inflight_htlc_msat: 0,
6397 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6399 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6400 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6401 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6403 // Then check we can get a normal route
6404 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6405 let route_params = RouteParameters::from_payment_params_and_value(
6406 payment_params, 100);
6407 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6408 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6409 assert!(route.is_ok());
6411 // Then check that we can't get a route if we ban an intermediate node.
6412 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6413 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6414 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6415 assert!(route.is_err());
6417 // Finally make sure we can route again, when we remove the ban.
6418 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6419 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6420 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6421 assert!(route.is_ok());
6425 fn abide_by_route_hint_max_htlc() {
6426 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6427 // params in the final route.
6428 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6429 let netgraph = network_graph.read_only();
6430 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6431 let scorer = ln_test_utils::TestScorer::new();
6432 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6433 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6434 let config = UserConfig::default();
6436 let max_htlc_msat = 50_000;
6437 let route_hint_1 = RouteHint(vec![RouteHintHop {
6438 src_node_id: nodes[2],
6439 short_channel_id: 42,
6442 proportional_millionths: 0,
6444 cltv_expiry_delta: 10,
6445 htlc_minimum_msat: None,
6446 htlc_maximum_msat: Some(max_htlc_msat),
6448 let dest_node_id = ln_test_utils::pubkey(42);
6449 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6450 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6451 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6453 // Make sure we'll error if our route hints don't have enough liquidity according to their
6454 // htlc_maximum_msat.
6455 let route_params = RouteParameters::from_payment_params_and_value(
6456 payment_params, max_htlc_msat + 1);
6457 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6458 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(),
6461 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6462 } else { panic!(); }
6464 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6465 let mut route_hint_2 = route_hint_1.clone();
6466 route_hint_2.0[0].short_channel_id = 43;
6467 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6468 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6469 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6470 let route_params = RouteParameters::from_payment_params_and_value(
6471 payment_params, max_htlc_msat + 1);
6472 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6473 &scorer, &(), &random_seed_bytes).unwrap();
6474 assert_eq!(route.paths.len(), 2);
6475 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6476 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6480 fn direct_channel_to_hints_with_max_htlc() {
6481 // Check that if we have a first hop channel peer that's connected to multiple provided route
6482 // hints, that we properly split the payment between the route hints if needed.
6483 let logger = Arc::new(ln_test_utils::TestLogger::new());
6484 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6485 let scorer = ln_test_utils::TestScorer::new();
6486 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6487 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6488 let config = UserConfig::default();
6490 let our_node_id = ln_test_utils::pubkey(42);
6491 let intermed_node_id = ln_test_utils::pubkey(43);
6492 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6494 let amt_msat = 900_000;
6495 let max_htlc_msat = 500_000;
6496 let route_hint_1 = RouteHint(vec![RouteHintHop {
6497 src_node_id: intermed_node_id,
6498 short_channel_id: 44,
6501 proportional_millionths: 0,
6503 cltv_expiry_delta: 10,
6504 htlc_minimum_msat: None,
6505 htlc_maximum_msat: Some(max_htlc_msat),
6507 src_node_id: intermed_node_id,
6508 short_channel_id: 45,
6511 proportional_millionths: 0,
6513 cltv_expiry_delta: 10,
6514 htlc_minimum_msat: None,
6515 // Check that later route hint max htlcs don't override earlier ones
6516 htlc_maximum_msat: Some(max_htlc_msat - 50),
6518 let mut route_hint_2 = route_hint_1.clone();
6519 route_hint_2.0[0].short_channel_id = 46;
6520 route_hint_2.0[1].short_channel_id = 47;
6521 let dest_node_id = ln_test_utils::pubkey(44);
6522 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6523 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6524 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6526 let route_params = RouteParameters::from_payment_params_and_value(
6527 payment_params, amt_msat);
6528 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6529 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6530 &random_seed_bytes).unwrap();
6531 assert_eq!(route.paths.len(), 2);
6532 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6533 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6534 assert_eq!(route.get_total_amount(), amt_msat);
6536 // Re-run but with two first hop channels connected to the same route hint peers that must be
6538 let first_hops = vec![
6539 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6540 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6542 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6543 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6544 &random_seed_bytes).unwrap();
6545 assert_eq!(route.paths.len(), 2);
6546 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6547 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6548 assert_eq!(route.get_total_amount(), amt_msat);
6550 // Make sure this works for blinded route hints.
6551 let blinded_path = BlindedPath {
6552 introduction_node_id: intermed_node_id,
6553 blinding_point: ln_test_utils::pubkey(42),
6555 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6556 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6559 let blinded_payinfo = BlindedPayInfo {
6561 fee_proportional_millionths: 0,
6562 htlc_minimum_msat: 1,
6563 htlc_maximum_msat: max_htlc_msat,
6564 cltv_expiry_delta: 10,
6565 features: BlindedHopFeatures::empty(),
6567 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6568 let payment_params = PaymentParameters::blinded(vec![
6569 (blinded_payinfo.clone(), blinded_path.clone()),
6570 (blinded_payinfo.clone(), blinded_path.clone())])
6571 .with_bolt12_features(bolt12_features).unwrap();
6572 let route_params = RouteParameters::from_payment_params_and_value(
6573 payment_params, amt_msat);
6574 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6575 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6576 &random_seed_bytes).unwrap();
6577 assert_eq!(route.paths.len(), 2);
6578 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6579 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6580 assert_eq!(route.get_total_amount(), amt_msat);
6584 fn blinded_route_ser() {
6585 let blinded_path_1 = BlindedPath {
6586 introduction_node_id: ln_test_utils::pubkey(42),
6587 blinding_point: ln_test_utils::pubkey(43),
6589 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6590 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6593 let blinded_path_2 = BlindedPath {
6594 introduction_node_id: ln_test_utils::pubkey(46),
6595 blinding_point: ln_test_utils::pubkey(47),
6597 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6598 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6601 // (De)serialize a Route with 1 blinded path out of two total paths.
6602 let mut route = Route { paths: vec![Path {
6603 hops: vec![RouteHop {
6604 pubkey: ln_test_utils::pubkey(50),
6605 node_features: NodeFeatures::empty(),
6606 short_channel_id: 42,
6607 channel_features: ChannelFeatures::empty(),
6609 cltv_expiry_delta: 0,
6611 blinded_tail: Some(BlindedTail {
6612 hops: blinded_path_1.blinded_hops,
6613 blinding_point: blinded_path_1.blinding_point,
6614 excess_final_cltv_expiry_delta: 40,
6615 final_value_msat: 100,
6617 hops: vec![RouteHop {
6618 pubkey: ln_test_utils::pubkey(51),
6619 node_features: NodeFeatures::empty(),
6620 short_channel_id: 43,
6621 channel_features: ChannelFeatures::empty(),
6623 cltv_expiry_delta: 0,
6624 }], blinded_tail: None }],
6627 let encoded_route = route.encode();
6628 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6629 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6630 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6632 // (De)serialize a Route with two paths, each containing a blinded tail.
6633 route.paths[1].blinded_tail = Some(BlindedTail {
6634 hops: blinded_path_2.blinded_hops,
6635 blinding_point: blinded_path_2.blinding_point,
6636 excess_final_cltv_expiry_delta: 41,
6637 final_value_msat: 101,
6639 let encoded_route = route.encode();
6640 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6641 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6642 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6646 fn blinded_path_inflight_processing() {
6647 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6648 // account for the blinded tail's final amount_msat.
6649 let mut inflight_htlcs = InFlightHtlcs::new();
6650 let blinded_path = BlindedPath {
6651 introduction_node_id: ln_test_utils::pubkey(43),
6652 blinding_point: ln_test_utils::pubkey(48),
6653 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6656 hops: vec![RouteHop {
6657 pubkey: ln_test_utils::pubkey(42),
6658 node_features: NodeFeatures::empty(),
6659 short_channel_id: 42,
6660 channel_features: ChannelFeatures::empty(),
6662 cltv_expiry_delta: 0,
6665 pubkey: blinded_path.introduction_node_id,
6666 node_features: NodeFeatures::empty(),
6667 short_channel_id: 43,
6668 channel_features: ChannelFeatures::empty(),
6670 cltv_expiry_delta: 0,
6672 blinded_tail: Some(BlindedTail {
6673 hops: blinded_path.blinded_hops,
6674 blinding_point: blinded_path.blinding_point,
6675 excess_final_cltv_expiry_delta: 0,
6676 final_value_msat: 200,
6679 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6680 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6681 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6685 fn blinded_path_cltv_shadow_offset() {
6686 // Make sure we add a shadow offset when sending to blinded paths.
6687 let blinded_path = BlindedPath {
6688 introduction_node_id: ln_test_utils::pubkey(43),
6689 blinding_point: ln_test_utils::pubkey(44),
6691 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6692 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6695 let mut route = Route { paths: vec![Path {
6696 hops: vec![RouteHop {
6697 pubkey: ln_test_utils::pubkey(42),
6698 node_features: NodeFeatures::empty(),
6699 short_channel_id: 42,
6700 channel_features: ChannelFeatures::empty(),
6702 cltv_expiry_delta: 0,
6705 pubkey: blinded_path.introduction_node_id,
6706 node_features: NodeFeatures::empty(),
6707 short_channel_id: 43,
6708 channel_features: ChannelFeatures::empty(),
6710 cltv_expiry_delta: 0,
6713 blinded_tail: Some(BlindedTail {
6714 hops: blinded_path.blinded_hops,
6715 blinding_point: blinded_path.blinding_point,
6716 excess_final_cltv_expiry_delta: 0,
6717 final_value_msat: 200,
6719 }], route_params: None};
6721 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6722 let (_, network_graph, _, _, _) = build_line_graph();
6723 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6724 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6725 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6729 fn simple_blinded_route_hints() {
6730 do_simple_blinded_route_hints(1);
6731 do_simple_blinded_route_hints(2);
6732 do_simple_blinded_route_hints(3);
6735 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6736 // Check that we can generate a route to a blinded path with the expected hops.
6737 let (secp_ctx, network, _, _, logger) = build_graph();
6738 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6739 let network_graph = network.read_only();
6741 let scorer = ln_test_utils::TestScorer::new();
6742 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6743 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6745 let mut blinded_path = BlindedPath {
6746 introduction_node_id: nodes[2],
6747 blinding_point: ln_test_utils::pubkey(42),
6748 blinded_hops: Vec::with_capacity(num_blinded_hops),
6750 for i in 0..num_blinded_hops {
6751 blinded_path.blinded_hops.push(
6752 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6755 let blinded_payinfo = BlindedPayInfo {
6757 fee_proportional_millionths: 500,
6758 htlc_minimum_msat: 1000,
6759 htlc_maximum_msat: 100_000_000,
6760 cltv_expiry_delta: 15,
6761 features: BlindedHopFeatures::empty(),
6764 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6765 let route_params = RouteParameters::from_payment_params_and_value(
6766 payment_params, 1001);
6767 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6768 &scorer, &(), &random_seed_bytes).unwrap();
6769 assert_eq!(route.paths.len(), 1);
6770 assert_eq!(route.paths[0].hops.len(), 2);
6772 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6773 assert_eq!(tail.hops, blinded_path.blinded_hops);
6774 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6775 assert_eq!(tail.final_value_msat, 1001);
6777 let final_hop = route.paths[0].hops.last().unwrap();
6778 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6779 if tail.hops.len() > 1 {
6780 assert_eq!(final_hop.fee_msat,
6781 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6782 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6784 assert_eq!(final_hop.fee_msat, 0);
6785 assert_eq!(final_hop.cltv_expiry_delta, 0);
6790 fn blinded_path_routing_errors() {
6791 // Check that we can generate a route to a blinded path with the expected hops.
6792 let (secp_ctx, network, _, _, logger) = build_graph();
6793 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6794 let network_graph = network.read_only();
6796 let scorer = ln_test_utils::TestScorer::new();
6797 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6798 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6800 let mut invalid_blinded_path = BlindedPath {
6801 introduction_node_id: nodes[2],
6802 blinding_point: ln_test_utils::pubkey(42),
6804 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
6807 let blinded_payinfo = BlindedPayInfo {
6809 fee_proportional_millionths: 500,
6810 htlc_minimum_msat: 1000,
6811 htlc_maximum_msat: 100_000_000,
6812 cltv_expiry_delta: 15,
6813 features: BlindedHopFeatures::empty(),
6816 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
6817 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
6818 let payment_params = PaymentParameters::blinded(vec![
6819 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
6820 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
6821 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6822 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6823 &scorer, &(), &random_seed_bytes)
6825 Err(LightningError { err, .. }) => {
6826 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
6828 _ => panic!("Expected error")
6831 invalid_blinded_path.introduction_node_id = our_id;
6832 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
6833 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6834 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6835 &(), &random_seed_bytes)
6837 Err(LightningError { err, .. }) => {
6838 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
6840 _ => panic!("Expected error")
6843 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
6844 invalid_blinded_path.blinded_hops.clear();
6845 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
6846 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6847 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6848 &(), &random_seed_bytes)
6850 Err(LightningError { err, .. }) => {
6851 assert_eq!(err, "0-hop blinded path provided");
6853 _ => panic!("Expected error")
6858 fn matching_intro_node_paths_provided() {
6859 // Check that if multiple blinded paths with the same intro node are provided in payment
6860 // parameters, we'll return the correct paths in the resulting MPP route.
6861 let (secp_ctx, network, _, _, logger) = build_graph();
6862 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6863 let network_graph = network.read_only();
6865 let scorer = ln_test_utils::TestScorer::new();
6866 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6867 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6868 let config = UserConfig::default();
6870 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6871 let blinded_path_1 = BlindedPath {
6872 introduction_node_id: nodes[2],
6873 blinding_point: ln_test_utils::pubkey(42),
6875 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6876 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6879 let blinded_payinfo_1 = BlindedPayInfo {
6881 fee_proportional_millionths: 0,
6882 htlc_minimum_msat: 0,
6883 htlc_maximum_msat: 30_000,
6884 cltv_expiry_delta: 0,
6885 features: BlindedHopFeatures::empty(),
6888 let mut blinded_path_2 = blinded_path_1.clone();
6889 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
6890 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
6891 blinded_payinfo_2.htlc_maximum_msat = 70_000;
6893 let blinded_hints = vec![
6894 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
6895 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
6897 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
6898 .with_bolt12_features(bolt12_features.clone()).unwrap();
6900 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
6901 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6902 &scorer, &(), &random_seed_bytes).unwrap();
6903 assert_eq!(route.paths.len(), 2);
6904 let mut total_amount_paid_msat = 0;
6905 for path in route.paths.into_iter() {
6906 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6907 if let Some(bt) = &path.blinded_tail {
6908 assert_eq!(bt.blinding_point,
6909 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
6910 .map(|(_, bp)| bp.blinding_point).unwrap());
6911 } else { panic!(); }
6912 total_amount_paid_msat += path.final_value_msat();
6914 assert_eq!(total_amount_paid_msat, 100_000);
6918 fn direct_to_intro_node() {
6919 // This previously caused a debug panic in the router when asserting
6920 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
6921 // direct channels we failed to account for the fee charged for use of the blinded path.
6924 // node0 -1(1)2 - node1
6925 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
6926 // doesn't account for the blinded path fee.
6928 let secp_ctx = Secp256k1::new();
6929 let logger = Arc::new(ln_test_utils::TestLogger::new());
6930 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6931 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
6932 let scorer = ln_test_utils::TestScorer::new();
6933 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6934 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6936 let amt_msat = 10_000_000;
6937 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
6938 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
6939 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6940 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
6941 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6942 short_channel_id: 1,
6945 cltv_expiry_delta: 42,
6946 htlc_minimum_msat: 1_000,
6947 htlc_maximum_msat: 10_000_000,
6949 fee_proportional_millionths: 0,
6950 excess_data: Vec::new()
6952 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6953 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6954 short_channel_id: 1,
6957 cltv_expiry_delta: 42,
6958 htlc_minimum_msat: 1_000,
6959 htlc_maximum_msat: 10_000_000,
6961 fee_proportional_millionths: 0,
6962 excess_data: Vec::new()
6964 let first_hops = vec![
6965 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6967 let blinded_path = BlindedPath {
6968 introduction_node_id: nodes[1],
6969 blinding_point: ln_test_utils::pubkey(42),
6971 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6972 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6975 let blinded_payinfo = BlindedPayInfo {
6976 fee_base_msat: 1000,
6977 fee_proportional_millionths: 0,
6978 htlc_minimum_msat: 1000,
6979 htlc_maximum_msat: MAX_VALUE_MSAT,
6980 cltv_expiry_delta: 0,
6981 features: BlindedHopFeatures::empty(),
6983 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
6985 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
6987 let netgraph = network_graph.read_only();
6988 let route_params = RouteParameters::from_payment_params_and_value(
6989 payment_params.clone(), amt_msat);
6990 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
6991 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6992 &random_seed_bytes) {
6993 assert_eq!(err, "Failed to find a path to the given destination");
6994 } else { panic!("Expected error") }
6996 // Sending an exact amount accounting for the blinded path fee works.
6997 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
6998 let route_params = RouteParameters::from_payment_params_and_value(
6999 payment_params, amt_minus_blinded_path_fee);
7000 let route = get_route(&nodes[0], &route_params, &netgraph,
7001 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
7002 &random_seed_bytes).unwrap();
7003 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7004 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7008 fn direct_to_matching_intro_nodes() {
7009 // This previously caused us to enter `unreachable` code in the following situation:
7010 // 1. We add a route candidate for intro_node contributing a high amount
7011 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7012 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7013 // amount, and update our route candidate for intro_node for the lower amount
7014 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7015 // lower contribution amount, but fail (this was previously caused by failure to account for
7016 // blinded path fees when adding first_hop<>intro_node candidates)
7017 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7018 // candidate still thinks its path is contributing the original higher amount. This caused us
7019 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7021 let secp_ctx = Secp256k1::new();
7022 let logger = Arc::new(ln_test_utils::TestLogger::new());
7023 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7024 let scorer = ln_test_utils::TestScorer::new();
7025 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7026 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7027 let config = UserConfig::default();
7029 // Values are taken from the fuzz input that uncovered this panic.
7030 let amt_msat = 21_7020_5185_1403_2640;
7031 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7032 let first_hops = vec![
7033 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7034 18446744073709551615)];
7036 let blinded_path = BlindedPath {
7037 introduction_node_id: nodes[1],
7038 blinding_point: ln_test_utils::pubkey(42),
7040 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7041 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7044 let blinded_payinfo = BlindedPayInfo {
7045 fee_base_msat: 5046_2720,
7046 fee_proportional_millionths: 0,
7047 htlc_minimum_msat: 4503_5996_2737_0496,
7048 htlc_maximum_msat: 45_0359_9627_3704_9600,
7049 cltv_expiry_delta: 0,
7050 features: BlindedHopFeatures::empty(),
7052 let mut blinded_hints = vec![
7053 (blinded_payinfo.clone(), blinded_path.clone()),
7054 (blinded_payinfo.clone(), blinded_path.clone()),
7056 blinded_hints[1].0.fee_base_msat = 419_4304;
7057 blinded_hints[1].0.fee_proportional_millionths = 257;
7058 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7059 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7060 blinded_hints[1].0.cltv_expiry_delta = 0;
7062 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7063 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7064 .with_bolt12_features(bolt12_features.clone()).unwrap();
7066 let netgraph = network_graph.read_only();
7067 let route_params = RouteParameters::from_payment_params_and_value(
7068 payment_params, amt_msat);
7069 let route = get_route(&nodes[0], &route_params, &netgraph,
7070 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
7071 &random_seed_bytes).unwrap();
7072 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7073 assert_eq!(route.get_total_amount(), amt_msat);
7077 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7078 pub(crate) mod bench_utils {
7082 use bitcoin::hashes::Hash;
7083 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7085 use crate::chain::transaction::OutPoint;
7086 use crate::routing::scoring::ScoreUpdate;
7087 use crate::sign::{EntropySource, KeysManager};
7088 use crate::ln::ChannelId;
7089 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7090 use crate::ln::features::Bolt11InvoiceFeatures;
7091 use crate::routing::gossip::NetworkGraph;
7092 use crate::util::config::UserConfig;
7093 use crate::util::ser::ReadableArgs;
7094 use crate::util::test_utils::TestLogger;
7096 /// Tries to open a network graph file, or panics with a URL to fetch it.
7097 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7098 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7099 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7100 .or_else(|_| { // Fall back to guessing based on the binary location
7101 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7102 let mut path = std::env::current_exe().unwrap();
7103 path.pop(); // lightning-...
7105 path.pop(); // debug
7106 path.pop(); // target
7107 path.push("lightning");
7108 path.push("net_graph-2023-01-18.bin");
7111 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7112 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7113 let mut path = std::env::current_exe().unwrap();
7114 path.pop(); // bench...
7116 path.pop(); // debug
7117 path.pop(); // target
7118 path.pop(); // bench
7119 path.push("lightning");
7120 path.push("net_graph-2023-01-18.bin");
7123 .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");
7124 #[cfg(require_route_graph_test)]
7125 return Ok(res.unwrap());
7126 #[cfg(not(require_route_graph_test))]
7130 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7131 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7134 pub(crate) fn payer_pubkey() -> PublicKey {
7135 let secp_ctx = Secp256k1::new();
7136 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7140 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7142 channel_id: ChannelId::new_zero(),
7143 counterparty: ChannelCounterparty {
7144 features: channelmanager::provided_init_features(&UserConfig::default()),
7146 unspendable_punishment_reserve: 0,
7147 forwarding_info: None,
7148 outbound_htlc_minimum_msat: None,
7149 outbound_htlc_maximum_msat: None,
7151 funding_txo: Some(OutPoint {
7152 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7155 short_channel_id: Some(1),
7156 inbound_scid_alias: None,
7157 outbound_scid_alias: None,
7158 channel_value_satoshis: 10_000_000_000,
7160 outbound_capacity_msat: 10_000_000_000,
7161 next_outbound_htlc_minimum_msat: 0,
7162 next_outbound_htlc_limit_msat: 10_000_000_000,
7163 inbound_capacity_msat: 0,
7164 unspendable_punishment_reserve: None,
7165 confirmations_required: None,
7166 confirmations: None,
7167 force_close_spend_delay: None,
7169 is_channel_ready: true,
7172 inbound_htlc_minimum_msat: None,
7173 inbound_htlc_maximum_msat: None,
7175 feerate_sat_per_1000_weight: None,
7176 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7180 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7181 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7182 starting_amount: u64, route_count: usize,
7183 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7184 let payer = payer_pubkey();
7185 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7186 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7188 let nodes = graph.read_only().nodes().clone();
7189 let mut route_endpoints = Vec::new();
7190 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7191 // with some routes we picked being un-routable.
7192 for _ in 0..route_count * 3 / 2 {
7194 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7195 let src = PublicKey::from_slice(nodes.unordered_keys()
7196 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7197 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7198 let dst = PublicKey::from_slice(nodes.unordered_keys()
7199 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7200 let params = PaymentParameters::from_node_id(dst, 42)
7201 .with_bolt11_features(features.clone()).unwrap();
7202 let first_hop = first_hop(src);
7203 let amt_msat = starting_amount + seed % 1_000_000;
7204 let route_params = RouteParameters::from_payment_params_and_value(
7205 params.clone(), amt_msat);
7207 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7208 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7210 // ...and seed the scorer with success and failure data...
7211 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7212 let mut score_amt = seed % 1_000_000_000;
7214 // Generate fail/success paths for a wider range of potential amounts with
7215 // MPP enabled to give us a chance to apply penalties for more potential
7217 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7218 let params = PaymentParameters::from_node_id(dst, 42)
7219 .with_bolt11_features(mpp_features).unwrap();
7220 let route_params = RouteParameters::from_payment_params_and_value(
7221 params.clone(), score_amt);
7222 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7223 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7224 &random_seed_bytes);
7225 if let Ok(route) = route_res {
7226 for path in route.paths {
7227 if seed & 0x80 == 0 {
7228 scorer.payment_path_successful(&path);
7230 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7231 scorer.payment_path_failed(&path, short_channel_id);
7233 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7237 // If we couldn't find a path with a higer amount, reduce and try again.
7241 route_endpoints.push((first_hop, params, amt_msat));
7247 // Because we've changed channel scores, it's possible we'll take different routes to the
7248 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7249 // requires a too-high CLTV delta.
7250 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7251 let route_params = RouteParameters::from_payment_params_and_value(
7252 params.clone(), *amt_msat);
7253 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7254 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7256 route_endpoints.truncate(route_count);
7257 assert_eq!(route_endpoints.len(), route_count);
7265 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7266 use crate::sign::{EntropySource, KeysManager};
7267 use crate::ln::channelmanager;
7268 use crate::ln::features::Bolt11InvoiceFeatures;
7269 use crate::routing::gossip::NetworkGraph;
7270 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7271 use crate::util::config::UserConfig;
7272 use crate::util::logger::{Logger, Record};
7273 use crate::util::test_utils::TestLogger;
7275 use criterion::Criterion;
7277 struct DummyLogger {}
7278 impl Logger for DummyLogger {
7279 fn log(&self, _record: &Record) {}
7282 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7283 let logger = TestLogger::new();
7284 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7285 let scorer = FixedPenaltyScorer::with_penalty(0);
7286 generate_routes(bench, &network_graph, scorer, &(), Bolt11InvoiceFeatures::empty(), 0,
7287 "generate_routes_with_zero_penalty_scorer");
7290 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7291 let logger = TestLogger::new();
7292 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7293 let scorer = FixedPenaltyScorer::with_penalty(0);
7294 generate_routes(bench, &network_graph, scorer, &(),
7295 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7296 "generate_mpp_routes_with_zero_penalty_scorer");
7299 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7300 let logger = TestLogger::new();
7301 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7302 let params = ProbabilisticScoringFeeParameters::default();
7303 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7304 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7305 "generate_routes_with_probabilistic_scorer");
7308 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7309 let logger = TestLogger::new();
7310 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7311 let params = ProbabilisticScoringFeeParameters::default();
7312 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7313 generate_routes(bench, &network_graph, scorer, ¶ms,
7314 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7315 "generate_mpp_routes_with_probabilistic_scorer");
7318 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7319 let logger = TestLogger::new();
7320 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7321 let params = ProbabilisticScoringFeeParameters::default();
7322 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7323 generate_routes(bench, &network_graph, scorer, ¶ms,
7324 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7325 "generate_large_mpp_routes_with_probabilistic_scorer");
7328 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7329 let logger = TestLogger::new();
7330 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7331 let mut params = ProbabilisticScoringFeeParameters::default();
7332 params.linear_success_probability = false;
7333 let scorer = ProbabilisticScorer::new(
7334 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7335 generate_routes(bench, &network_graph, scorer, ¶ms,
7336 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7337 "generate_routes_with_nonlinear_probabilistic_scorer");
7340 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7341 let logger = TestLogger::new();
7342 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7343 let mut params = ProbabilisticScoringFeeParameters::default();
7344 params.linear_success_probability = false;
7345 let scorer = ProbabilisticScorer::new(
7346 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7347 generate_routes(bench, &network_graph, scorer, ¶ms,
7348 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7349 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
7352 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7353 let logger = TestLogger::new();
7354 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7355 let mut params = ProbabilisticScoringFeeParameters::default();
7356 params.linear_success_probability = false;
7357 let scorer = ProbabilisticScorer::new(
7358 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7359 generate_routes(bench, &network_graph, scorer, ¶ms,
7360 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7361 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
7364 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7365 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7366 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7367 bench_name: &'static str,
7369 let payer = bench_utils::payer_pubkey();
7370 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7371 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7373 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7374 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7376 // ...then benchmark finding paths between the nodes we learned.
7378 bench.bench_function(bench_name, |b| b.iter(|| {
7379 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
7380 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
7381 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7382 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());