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 `payment_params` parameter passed via [`RouteParameters`] to [`find_route`].
342 /// This is used by `ChannelManager` to track information which may be required for retries.
343 pub payment_params: Option<PaymentParameters>,
347 /// Returns the total amount of fees paid on this [`Route`].
349 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
350 /// the amount passed to [`find_route`]'s `route_params.final_value_msat`.
351 pub fn get_total_fees(&self) -> u64 {
352 self.paths.iter().map(|path| path.fee_msat()).sum()
355 /// Returns the total amount paid on this [`Route`], excluding the fees. Might be more than
356 /// requested if we had to reach htlc_minimum_msat.
357 pub fn get_total_amount(&self) -> u64 {
358 self.paths.iter().map(|path| path.final_value_msat()).sum()
362 const SERIALIZATION_VERSION: u8 = 1;
363 const MIN_SERIALIZATION_VERSION: u8 = 1;
365 impl Writeable for Route {
366 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
367 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
368 (self.paths.len() as u64).write(writer)?;
369 let mut blinded_tails = Vec::new();
370 for path in self.paths.iter() {
371 (path.hops.len() as u8).write(writer)?;
372 for (idx, hop) in path.hops.iter().enumerate() {
374 if let Some(blinded_tail) = &path.blinded_tail {
375 if blinded_tails.is_empty() {
376 blinded_tails = Vec::with_capacity(path.hops.len());
378 blinded_tails.push(None);
381 blinded_tails.push(Some(blinded_tail));
382 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
385 write_tlv_fields!(writer, {
386 (1, self.payment_params, option),
387 (2, blinded_tails, optional_vec),
393 impl Readable for Route {
394 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
395 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
396 let path_count: u64 = Readable::read(reader)?;
397 if path_count == 0 { return Err(DecodeError::InvalidValue); }
398 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
399 let mut min_final_cltv_expiry_delta = u32::max_value();
400 for _ in 0..path_count {
401 let hop_count: u8 = Readable::read(reader)?;
402 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
403 for _ in 0..hop_count {
404 hops.push(Readable::read(reader)?);
406 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
407 min_final_cltv_expiry_delta =
408 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
409 paths.push(Path { hops, blinded_tail: None });
411 _init_and_read_len_prefixed_tlv_fields!(reader, {
412 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
413 (2, blinded_tails, optional_vec),
415 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
416 if blinded_tails.len() != 0 {
417 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
418 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
419 path.blinded_tail = blinded_tail_opt;
422 Ok(Route { paths, payment_params })
426 /// Parameters needed to find a [`Route`].
428 /// Passed to [`find_route`] and [`build_route_from_hops`].
429 #[derive(Clone, Debug, PartialEq, Eq)]
430 pub struct RouteParameters {
431 /// The parameters of the failed payment path.
432 pub payment_params: PaymentParameters,
434 /// The amount in msats sent on the failed payment path.
435 pub final_value_msat: u64,
438 impl RouteParameters {
439 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
440 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
441 Self { payment_params, final_value_msat }
445 impl Writeable for RouteParameters {
446 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
447 write_tlv_fields!(writer, {
448 (0, self.payment_params, required),
449 (2, self.final_value_msat, required),
450 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
451 // `RouteParameters` directly. For compatibility, we write it here.
452 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
458 impl Readable for RouteParameters {
459 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
460 _init_and_read_len_prefixed_tlv_fields!(reader, {
461 (0, payment_params, (required: ReadableArgs, 0)),
462 (2, final_value_msat, required),
463 (4, final_cltv_delta, option),
465 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
466 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
467 if final_cltv_expiry_delta == &0 {
468 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
473 final_value_msat: final_value_msat.0.unwrap(),
478 /// Maximum total CTLV difference we allow for a full payment path.
479 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
481 /// Maximum number of paths we allow an (MPP) payment to have.
482 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
483 // limits, but for now more than 10 paths likely carries too much one-path failure.
484 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
486 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
488 // The median hop CLTV expiry delta currently seen in the network.
489 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
491 // During routing, we only consider paths shorter than our maximum length estimate.
492 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
493 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
494 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
496 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
497 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
498 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
499 // (payment_secret and total_msat) = 93 bytes for the final hop.
500 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
501 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
502 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
504 /// Information used to route a payment.
505 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
506 pub struct PaymentParameters {
507 /// Information about the payee, such as their features and route hints for their channels.
510 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
511 pub expiry_time: Option<u64>,
513 /// The maximum total CLTV delta we accept for the route.
514 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
515 pub max_total_cltv_expiry_delta: u32,
517 /// The maximum number of paths that may be used by (MPP) payments.
518 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
519 pub max_path_count: u8,
521 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
522 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
523 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
524 /// increasing failure probability for those paths.
526 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
527 /// restriction have been found. While paths which meet this criteria will be searched for, it
528 /// is ultimately up to the scorer to select them over other paths.
530 /// A value of 0 will allow payments up to and including a channel's total announced usable
531 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
534 pub max_channel_saturation_power_of_half: u8,
536 /// A list of SCIDs which this payment was previously attempted over and which caused the
537 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
539 pub previously_failed_channels: Vec<u64>,
542 impl Writeable for PaymentParameters {
543 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
544 let mut clear_hints = &vec![];
545 let mut blinded_hints = &vec![];
547 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
548 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
550 write_tlv_fields!(writer, {
551 (0, self.payee.node_id(), option),
552 (1, self.max_total_cltv_expiry_delta, required),
553 (2, self.payee.features(), option),
554 (3, self.max_path_count, required),
555 (4, *clear_hints, required_vec),
556 (5, self.max_channel_saturation_power_of_half, required),
557 (6, self.expiry_time, option),
558 (7, self.previously_failed_channels, required_vec),
559 (8, *blinded_hints, optional_vec),
560 (9, self.payee.final_cltv_expiry_delta(), option),
566 impl ReadableArgs<u32> for PaymentParameters {
567 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
568 _init_and_read_len_prefixed_tlv_fields!(reader, {
569 (0, payee_pubkey, option),
570 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
571 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
572 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
573 (4, clear_route_hints, required_vec),
574 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
575 (6, expiry_time, option),
576 (7, previously_failed_channels, optional_vec),
577 (8, blinded_route_hints, optional_vec),
578 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
580 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
581 let payee = if blinded_route_hints.len() != 0 {
582 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
584 route_hints: blinded_route_hints,
585 features: features.and_then(|f: Features| f.bolt12()),
589 route_hints: clear_route_hints,
590 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
591 features: features.and_then(|f| f.bolt11()),
592 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
596 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
597 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
599 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
601 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
607 impl PaymentParameters {
608 /// Creates a payee with the node id of the given `pubkey`.
610 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
612 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
614 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
616 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
617 max_path_count: DEFAULT_MAX_PATH_COUNT,
618 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
619 previously_failed_channels: Vec::new(),
623 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
625 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
628 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
629 /// whether your router will be allowed to find a multi-part route for this payment. If you
630 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
631 /// [`RecipientOnionFields::secret_only`].
633 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
634 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
635 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
636 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
637 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
640 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
641 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
642 /// [`PaymentParameters::expiry_time`].
643 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
644 Self::blinded(invoice.payment_paths().to_vec())
645 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
646 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
649 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
650 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
652 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
654 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
655 max_path_count: DEFAULT_MAX_PATH_COUNT,
656 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
657 previously_failed_channels: Vec::new(),
661 /// Includes the payee's features. Errors if the parameters were not initialized with
662 /// [`PaymentParameters::from_bolt12_invoice`].
664 /// This is not exported to bindings users since bindings don't support move semantics
665 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
667 Payee::Clear { .. } => Err(()),
668 Payee::Blinded { route_hints, .. } =>
669 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
673 /// Includes the payee's features. Errors if the parameters were initialized with
674 /// [`PaymentParameters::from_bolt12_invoice`].
676 /// This is not exported to bindings users since bindings don't support move semantics
677 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
679 Payee::Blinded { .. } => Err(()),
680 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
682 payee: Payee::Clear {
683 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
689 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
690 /// [`PaymentParameters::from_bolt12_invoice`].
692 /// This is not exported to bindings users since bindings don't support move semantics
693 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
695 Payee::Blinded { .. } => Err(()),
696 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
698 payee: Payee::Clear {
699 route_hints, node_id, features, final_cltv_expiry_delta,
705 /// Includes a payment expiration in seconds relative to the UNIX epoch.
707 /// This is not exported to bindings users since bindings don't support move semantics
708 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
709 Self { expiry_time: Some(expiry_time), ..self }
712 /// Includes a limit for the total CLTV expiry delta which is considered during routing
714 /// This is not exported to bindings users since bindings don't support move semantics
715 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
716 Self { max_total_cltv_expiry_delta, ..self }
719 /// Includes a limit for the maximum number of payment paths that may be used.
721 /// This is not exported to bindings users since bindings don't support move semantics
722 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
723 Self { max_path_count, ..self }
726 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
727 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
729 /// This is not exported to bindings users since bindings don't support move semantics
730 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
731 Self { max_channel_saturation_power_of_half, ..self }
735 /// The recipient of a payment, differing based on whether they've hidden their identity with route
737 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
739 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
740 /// will be included in the final [`Route`].
742 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
744 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
745 /// Features supported by the payee.
747 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
749 features: Option<Bolt12InvoiceFeatures>,
751 /// The recipient included these route hints in their BOLT11 invoice.
753 /// The node id of the payee.
755 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
756 route_hints: Vec<RouteHint>,
757 /// Features supported by the payee.
759 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
760 /// does not contain any features.
762 /// [`for_keysend`]: PaymentParameters::for_keysend
763 features: Option<Bolt11InvoiceFeatures>,
764 /// The minimum CLTV delta at the end of the route. This value must not be zero.
765 final_cltv_expiry_delta: u32,
770 fn node_id(&self) -> Option<PublicKey> {
772 Self::Clear { node_id, .. } => Some(*node_id),
776 fn node_features(&self) -> Option<NodeFeatures> {
778 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
779 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
782 fn supports_basic_mpp(&self) -> bool {
784 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
785 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
788 fn features(&self) -> Option<FeaturesRef> {
790 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
791 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
794 fn final_cltv_expiry_delta(&self) -> Option<u32> {
796 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
800 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
802 Self::Blinded { route_hints, .. } => &route_hints[..],
803 Self::Clear { .. } => &[]
807 fn unblinded_route_hints(&self) -> &[RouteHint] {
809 Self::Blinded { .. } => &[],
810 Self::Clear { route_hints, .. } => &route_hints[..]
815 enum FeaturesRef<'a> {
816 Bolt11(&'a Bolt11InvoiceFeatures),
817 Bolt12(&'a Bolt12InvoiceFeatures),
820 Bolt11(Bolt11InvoiceFeatures),
821 Bolt12(Bolt12InvoiceFeatures),
825 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
827 Self::Bolt12(f) => Some(f),
831 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
833 Self::Bolt11(f) => Some(f),
839 impl<'a> Writeable for FeaturesRef<'a> {
840 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
842 Self::Bolt11(f) => Ok(f.write(w)?),
843 Self::Bolt12(f) => Ok(f.write(w)?),
848 impl ReadableArgs<bool> for Features {
849 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
850 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
851 Ok(Self::Bolt12(Readable::read(reader)?))
855 /// A list of hops along a payment path terminating with a channel to the recipient.
856 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
857 pub struct RouteHint(pub Vec<RouteHintHop>);
859 impl Writeable for RouteHint {
860 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
861 (self.0.len() as u64).write(writer)?;
862 for hop in self.0.iter() {
869 impl Readable for RouteHint {
870 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
871 let hop_count: u64 = Readable::read(reader)?;
872 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
873 for _ in 0..hop_count {
874 hops.push(Readable::read(reader)?);
880 /// A channel descriptor for a hop along a payment path.
881 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
882 pub struct RouteHintHop {
883 /// The node_id of the non-target end of the route
884 pub src_node_id: PublicKey,
885 /// The short_channel_id of this channel
886 pub short_channel_id: u64,
887 /// The fees which must be paid to use this channel
888 pub fees: RoutingFees,
889 /// The difference in CLTV values between this node and the next node.
890 pub cltv_expiry_delta: u16,
891 /// The minimum value, in msat, which must be relayed to the next hop.
892 pub htlc_minimum_msat: Option<u64>,
893 /// The maximum value in msat available for routing with a single HTLC.
894 pub htlc_maximum_msat: Option<u64>,
897 impl_writeable_tlv_based!(RouteHintHop, {
898 (0, src_node_id, required),
899 (1, htlc_minimum_msat, option),
900 (2, short_channel_id, required),
901 (3, htlc_maximum_msat, option),
903 (6, cltv_expiry_delta, required),
906 #[derive(Eq, PartialEq)]
907 struct RouteGraphNode {
909 lowest_fee_to_node: u64,
910 total_cltv_delta: u32,
911 // The maximum value a yet-to-be-constructed payment path might flow through this node.
912 // This value is upper-bounded by us by:
913 // - how much is needed for a path being constructed
914 // - how much value can channels following this node (up to the destination) can contribute,
915 // considering their capacity and fees
916 value_contribution_msat: u64,
917 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
918 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
919 path_htlc_minimum_msat: u64,
920 /// All penalties incurred from this hop on the way to the destination, as calculated using
922 path_penalty_msat: u64,
923 /// The number of hops walked up to this node.
924 path_length_to_node: u8,
927 impl cmp::Ord for RouteGraphNode {
928 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
929 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
930 .saturating_add(other.path_penalty_msat);
931 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
932 .saturating_add(self.path_penalty_msat);
933 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
937 impl cmp::PartialOrd for RouteGraphNode {
938 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
939 Some(self.cmp(other))
943 /// A wrapper around the various hop representations.
945 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
946 #[derive(Clone, Debug)]
947 enum CandidateRouteHop<'a> {
948 /// A hop from the payer, where the outbound liquidity is known.
950 details: &'a ChannelDetails,
952 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
954 info: DirectedChannelInfo<'a>,
955 short_channel_id: u64,
957 /// A hop to the payee found in the BOLT 11 payment invoice, though not necessarily a direct
960 hint: &'a RouteHintHop,
962 /// The payee's identity is concealed behind blinded paths provided in a BOLT 12 invoice.
964 hint: &'a (BlindedPayInfo, BlindedPath),
967 /// Similar to [`Self::Blinded`], but the path here has 1 blinded hop. `BlindedPayInfo` provided
968 /// for 1-hop blinded paths is ignored because it is meant to apply to the hops *between* the
969 /// introduction node and the destination. Useful for tracking that we need to include a blinded
970 /// path at the end of our [`Route`].
972 hint: &'a (BlindedPayInfo, BlindedPath),
977 impl<'a> CandidateRouteHop<'a> {
978 fn short_channel_id(&self) -> Option<u64> {
980 CandidateRouteHop::FirstHop { details } => Some(details.get_outbound_payment_scid().unwrap()),
981 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
982 CandidateRouteHop::PrivateHop { hint } => Some(hint.short_channel_id),
983 CandidateRouteHop::Blinded { .. } => None,
984 CandidateRouteHop::OneHopBlinded { .. } => None,
988 // NOTE: This may alloc memory so avoid calling it in a hot code path.
989 fn features(&self) -> ChannelFeatures {
991 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
992 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
993 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
994 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
995 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
999 fn cltv_expiry_delta(&self) -> u32 {
1001 CandidateRouteHop::FirstHop { .. } => 0,
1002 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1003 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
1004 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1005 CandidateRouteHop::OneHopBlinded { .. } => 0,
1009 fn htlc_minimum_msat(&self) -> u64 {
1011 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat,
1012 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1013 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
1014 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1015 CandidateRouteHop::OneHopBlinded { .. } => 0,
1019 fn fees(&self) -> RoutingFees {
1021 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1022 base_msat: 0, proportional_millionths: 0,
1024 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1025 CandidateRouteHop::PrivateHop { hint } => hint.fees,
1026 CandidateRouteHop::Blinded { hint, .. } => {
1028 base_msat: hint.0.fee_base_msat,
1029 proportional_millionths: hint.0.fee_proportional_millionths
1032 CandidateRouteHop::OneHopBlinded { .. } =>
1033 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1037 fn effective_capacity(&self) -> EffectiveCapacity {
1039 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
1040 liquidity_msat: details.next_outbound_htlc_limit_msat,
1042 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1043 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }} =>
1044 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1045 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }} =>
1046 EffectiveCapacity::Infinite,
1047 CandidateRouteHop::Blinded { hint, .. } =>
1048 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1049 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1053 fn id(&self, channel_direction: bool /* src_node_id < target_node_id */) -> CandidateHopId {
1055 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1056 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1057 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), channel_direction)),
1060 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1062 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1070 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1071 enum CandidateHopId {
1072 /// Contains (scid, src_node_id < target_node_id)
1074 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1079 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1080 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1082 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1083 EffectiveCapacity::Infinite => u64::max_value(),
1084 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1085 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1086 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1087 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1088 // expected to have been generated from up-to-date capacity information.
1089 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1090 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1091 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1095 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1096 -> bool where I1::Item: PartialEq<I2::Item> {
1098 let a = iter_a.next();
1099 let b = iter_b.next();
1100 if a.is_none() && b.is_none() { return true; }
1101 if a.is_none() || b.is_none() { return false; }
1102 if a.unwrap().ne(&b.unwrap()) { return false; }
1106 /// It's useful to keep track of the hops associated with the fees required to use them,
1107 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1108 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1109 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1111 struct PathBuildingHop<'a> {
1112 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
1113 // is a larger refactor and will require careful performance analysis.
1115 candidate: CandidateRouteHop<'a>,
1118 /// All the fees paid *after* this channel on the way to the destination
1119 next_hops_fee_msat: u64,
1120 /// Fee paid for the use of the current channel (see candidate.fees()).
1121 /// The value will be actually deducted from the counterparty balance on the previous link.
1122 hop_use_fee_msat: u64,
1123 /// Used to compare channels when choosing the for routing.
1124 /// Includes paying for the use of a hop and the following hops, as well as
1125 /// an estimated cost of reaching this hop.
1126 /// Might get stale when fees are recomputed. Primarily for internal use.
1127 total_fee_msat: u64,
1128 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1129 /// walk and may be invalid thereafter.
1130 path_htlc_minimum_msat: u64,
1131 /// All penalties incurred from this channel on the way to the destination, as calculated using
1132 /// channel scoring.
1133 path_penalty_msat: u64,
1134 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1135 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1136 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1137 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1138 /// avoid processing them again.
1139 was_processed: bool,
1140 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1141 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1142 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1143 // value_contribution_msat, which requires tracking it here. See comments below where it is
1144 // used for more info.
1145 value_contribution_msat: u64,
1148 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1149 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1150 let mut debug_struct = f.debug_struct("PathBuildingHop");
1152 .field("node_id", &self.node_id)
1153 .field("short_channel_id", &self.candidate.short_channel_id())
1154 .field("total_fee_msat", &self.total_fee_msat)
1155 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1156 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1157 .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)))
1158 .field("path_penalty_msat", &self.path_penalty_msat)
1159 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1160 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1161 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1162 let debug_struct = debug_struct
1163 .field("value_contribution_msat", &self.value_contribution_msat);
1164 debug_struct.finish()
1168 // Instantiated with a list of hops with correct data in them collected during path finding,
1169 // an instance of this struct should be further modified only via given methods.
1171 struct PaymentPath<'a> {
1172 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1175 impl<'a> PaymentPath<'a> {
1176 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1177 fn get_value_msat(&self) -> u64 {
1178 self.hops.last().unwrap().0.fee_msat
1181 fn get_path_penalty_msat(&self) -> u64 {
1182 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1185 fn get_total_fee_paid_msat(&self) -> u64 {
1186 if self.hops.len() < 1 {
1190 // Can't use next_hops_fee_msat because it gets outdated.
1191 for (i, (hop, _)) in self.hops.iter().enumerate() {
1192 if i != self.hops.len() - 1 {
1193 result += hop.fee_msat;
1199 fn get_cost_msat(&self) -> u64 {
1200 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1203 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1204 // to change fees may result in an inconsistency.
1206 // Sometimes we call this function right after constructing a path which is inconsistent in
1207 // that it the value being transferred has decreased while we were doing path finding, leading
1208 // to the fees being paid not lining up with the actual limits.
1210 // Note that this function is not aware of the available_liquidity limit, and thus does not
1211 // support increasing the value being transferred beyond what was selected during the initial
1213 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
1214 let mut total_fee_paid_msat = 0 as u64;
1215 for i in (0..self.hops.len()).rev() {
1216 let last_hop = i == self.hops.len() - 1;
1218 // For non-last-hop, this value will represent the fees paid on the current hop. It
1219 // will consist of the fees for the use of the next hop, and extra fees to match
1220 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1221 let mut cur_hop_fees_msat = 0;
1223 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1226 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1227 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1228 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1229 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1230 // set it too high just to maliciously take more fees by exploiting this
1231 // match htlc_minimum_msat logic.
1232 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1233 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1234 // Note that there is a risk that *previous hops* (those closer to us, as we go
1235 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1237 // This might make us end up with a broken route, although this should be super-rare
1238 // in practice, both because of how healthy channels look like, and how we pick
1239 // channels in add_entry.
1240 // Also, this can't be exploited more heavily than *announce a free path and fail
1242 cur_hop_transferred_amount_msat += extra_fees_msat;
1243 total_fee_paid_msat += extra_fees_msat;
1244 cur_hop_fees_msat += extra_fees_msat;
1248 // Final hop is a special case: it usually has just value_msat (by design), but also
1249 // it still could overpay for the htlc_minimum_msat.
1250 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1252 // Propagate updated fees for the use of the channels to one hop back, where they
1253 // will be actually paid (fee_msat). The last hop is handled above separately.
1254 cur_hop.fee_msat = cur_hop_fees_msat;
1257 // Fee for the use of the current hop which will be deducted on the previous hop.
1258 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1259 // this channel is free for us.
1261 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1262 cur_hop.hop_use_fee_msat = new_fee;
1263 total_fee_paid_msat += new_fee;
1265 // It should not be possible because this function is called only to reduce the
1266 // value. In that case, compute_fee was already called with the same fees for
1267 // larger amount and there was no overflow.
1276 /// Calculate the fees required to route the given amount over a channel with the given fees.
1277 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1278 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1279 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1283 /// Calculate the fees required to route the given amount over a channel with the given fees,
1284 /// saturating to [`u64::max_value`].
1285 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1286 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1287 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1288 .saturating_add(channel_fees.base_msat as u64)
1291 /// The default `features` we assume for a node in a route, when no `features` are known about that
1294 /// Default features are:
1295 /// * variable_length_onion_optional
1296 fn default_node_features() -> NodeFeatures {
1297 let mut features = NodeFeatures::empty();
1298 features.set_variable_length_onion_optional();
1302 struct LoggedPayeePubkey(Option<PublicKey>);
1303 impl fmt::Display for LoggedPayeePubkey {
1304 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1307 "payee node id ".fmt(f)?;
1311 "blinded payee".fmt(f)
1317 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1318 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1319 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1321 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1322 "blinded route hint with introduction node id ".fmt(f)?;
1323 hint.1.introduction_node_id.fmt(f)?;
1324 " and blinding point ".fmt(f)?;
1325 hint.1.blinding_point.fmt(f)
1327 CandidateRouteHop::FirstHop { .. } => {
1328 "first hop with SCID ".fmt(f)?;
1329 self.0.short_channel_id().unwrap().fmt(f)
1331 CandidateRouteHop::PrivateHop { .. } => {
1332 "route hint with SCID ".fmt(f)?;
1333 self.0.short_channel_id().unwrap().fmt(f)
1337 self.0.short_channel_id().unwrap().fmt(f)
1344 fn sort_first_hop_channels(
1345 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1346 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1348 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1349 // most like to use.
1351 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1352 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1355 // Second, because simply always sorting in descending order would always use our largest
1356 // available outbound capacity, needlessly fragmenting our available channel capacities,
1357 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1358 // which have enough, but not too much, capacity for the payment.
1360 // Available outbound balances factor in liquidity already reserved for previously found paths.
1361 channels.sort_unstable_by(|chan_a, chan_b| {
1362 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1363 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1364 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1365 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1366 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1367 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1368 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1369 // Sort in descending order
1370 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1372 // Sort in ascending order
1373 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1378 /// Finds a route from us (payer) to the given target node (payee).
1380 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1381 /// in the given [`RouteParameters::payment_params`].
1382 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1384 /// Private routing paths between a public node and the target may be included in the `payee` field
1385 /// of [`RouteParameters::payment_params`].
1387 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1388 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1389 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1391 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1392 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1393 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1397 /// Panics if first_hops contains channels without `short_channel_id`s;
1398 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1400 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1401 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1402 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1403 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1404 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1405 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1406 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1407 ) -> Result<Route, LightningError>
1408 where L::Target: Logger, GL::Target: Logger {
1409 let graph_lock = network_graph.read_only();
1410 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1411 scorer, score_params, random_seed_bytes)?;
1412 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1416 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1417 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1418 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1419 _random_seed_bytes: &[u8; 32]
1420 ) -> Result<Route, LightningError>
1421 where L::Target: Logger {
1423 let payment_params = &route_params.payment_params;
1424 let final_value_msat = route_params.final_value_msat;
1425 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1426 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1427 // so use a dummy id for this in the blinded case.
1428 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1429 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1430 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1431 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1432 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1434 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1435 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1438 if final_value_msat > MAX_VALUE_MSAT {
1439 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1442 if final_value_msat == 0 {
1443 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1446 match &payment_params.payee {
1447 Payee::Clear { route_hints, node_id, .. } => {
1448 for route in route_hints.iter() {
1449 for hop in &route.0 {
1450 if hop.src_node_id == *node_id {
1451 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1456 Payee::Blinded { route_hints, .. } => {
1457 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1458 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});
1460 for (_, blinded_path) in route_hints.iter() {
1461 if blinded_path.blinded_hops.len() == 0 {
1462 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1463 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1464 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1465 } else if blinded_path.blinded_hops.len() == 1 &&
1466 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1467 && p.introduction_node_id != blinded_path.introduction_node_id)
1469 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1474 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1475 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1476 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});
1479 // The general routing idea is the following:
1480 // 1. Fill first/last hops communicated by the caller.
1481 // 2. Attempt to construct a path from payer to payee for transferring
1482 // any ~sufficient (described later) value.
1483 // If succeed, remember which channels were used and how much liquidity they have available,
1484 // so that future paths don't rely on the same liquidity.
1485 // 3. Proceed to the next step if:
1486 // - we hit the recommended target value;
1487 // - OR if we could not construct a new path. Any next attempt will fail too.
1488 // Otherwise, repeat step 2.
1489 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1490 // (not recommended value).
1491 // 5. If yes, proceed. If not, fail routing.
1492 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1493 // transferred up to the transfer target value.
1494 // 7. Reduce the value of the last path until we are sending only the target value.
1495 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1496 // them so that we're not sending two HTLCs along the same path.
1498 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1499 // distance from the payee
1501 // We are not a faithful Dijkstra's implementation because we can change values which impact
1502 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1503 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1504 // the value we are currently attempting to send over a path, we simply reduce the value being
1505 // sent along the path for any hops after that channel. This may imply that later fees (which
1506 // we've already tabulated) are lower because a smaller value is passing through the channels
1507 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1508 // channels which were selected earlier (and which may still be used for other paths without a
1509 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1512 // One potentially problematic case for this algorithm would be if there are many
1513 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1514 // graph walking), we may never find a path which is not liquidity-limited and has lower
1515 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1516 // Because we only consider paths with at least 5% of the total value being sent, the damage
1517 // from such a case should be limited, however this could be further reduced in the future by
1518 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1519 // limits for the purposes of fee calculation.
1521 // Alternatively, we could store more detailed path information in the heap (targets, below)
1522 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1523 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1524 // and practically (as we would need to store dynamically-allocated path information in heap
1525 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1526 // results of such an algorithm would likely be biased towards lower-value paths.
1528 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1529 // outside of our current search value, running a path search more times to gather candidate
1530 // paths at different values. While this may be acceptable, further path searches may increase
1531 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1532 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1533 // the same time, remaining generic across different payment values.
1535 let network_channels = network_graph.channels();
1536 let network_nodes = network_graph.nodes();
1538 if payment_params.max_path_count == 0 {
1539 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1542 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1543 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1545 let allow_mpp = if payment_params.max_path_count == 1 {
1547 } else if payment_params.payee.supports_basic_mpp() {
1549 } else if let Some(payee) = payee_node_id_opt {
1550 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1551 |info| info.features.supports_basic_mpp()))
1554 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1555 LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
1556 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1559 // Prepare the data we'll use for payee-to-payer search by
1560 // inserting first hops suggested by the caller as targets.
1561 // Our search will then attempt to reach them while traversing from the payee node.
1562 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1563 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1564 if let Some(hops) = first_hops {
1566 if chan.get_outbound_payment_scid().is_none() {
1567 panic!("first_hops should be filled in with usable channels, not pending ones");
1569 if chan.counterparty.node_id == *our_node_pubkey {
1570 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1573 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1574 .or_insert(Vec::new())
1577 if first_hop_targets.is_empty() {
1578 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1582 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1583 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1584 // adding duplicate entries when we find a better path to a given node.
1585 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1587 // Map from node_id to information about the best current path to that node, including feerate
1589 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1591 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1592 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1593 // htlc_minimum with extra fees while still finding a cheaper path.
1594 let mut hit_minimum_limit;
1596 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1597 // We start with a path_value of the exact amount we want, and if that generates a route we may
1598 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1599 // amount we want in total across paths, selecting the best subset at the end.
1600 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1601 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1602 let mut path_value_msat = final_value_msat;
1604 // Routing Fragmentation Mitigation heuristic:
1606 // Routing fragmentation across many payment paths increases the overall routing
1607 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1608 // Taking too many smaller paths also increases the chance of payment failure.
1609 // Thus to avoid this effect, we require from our collected links to provide
1610 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1611 // This requirement is currently set to be 1/max_path_count of the payment
1612 // value to ensure we only ever return routes that do not violate this limit.
1613 let minimal_value_contribution_msat: u64 = if allow_mpp {
1614 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1619 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1620 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1621 // drop the requirement by setting this to 0.
1622 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1624 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1625 // determine if the channel can be used by additional MPP paths or to inform path finding
1626 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1627 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1629 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1630 HashMap::with_capacity(network_nodes.len());
1632 // Keeping track of how much value we already collected across other paths. Helps to decide
1633 // when we want to stop looking for new paths.
1634 let mut already_collected_value_msat = 0;
1636 for (_, channels) in first_hop_targets.iter_mut() {
1637 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1641 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1642 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1644 // Remember how many candidates we ignored to allow for some logging afterwards.
1645 let mut num_ignored_value_contribution = 0;
1646 let mut num_ignored_path_length_limit = 0;
1647 let mut num_ignored_cltv_delta_limit = 0;
1648 let mut num_ignored_previously_failed = 0;
1650 macro_rules! add_entry {
1651 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1652 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1653 // since that value has to be transferred over this channel.
1654 // Returns whether this channel caused an update to `targets`.
1655 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1656 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1657 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1658 // We "return" whether we updated the path at the end, and how much we can route via
1659 // this channel, via this:
1660 let mut did_add_update_path_to_src_node = None;
1661 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1662 // practice these cases should be caught earlier:
1663 // - for regular channels at channel announcement (TODO)
1664 // - for first and last hops early in get_route
1665 if $src_node_id != $dest_node_id {
1666 let scid_opt = $candidate.short_channel_id();
1667 let effective_capacity = $candidate.effective_capacity();
1668 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1670 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1671 // It may be misleading because we might later choose to reduce the value transferred
1672 // over these channels, and the channel which was insufficient might become sufficient.
1673 // Worst case: we drop a good channel here because it can't cover the high following
1674 // fees caused by one expensive channel, but then this channel could have been used
1675 // if the amount being transferred over this path is lower.
1676 // We do this for now, but this is a subject for removal.
1677 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1678 let used_liquidity_msat = used_liquidities
1679 .get(&$candidate.id($src_node_id < $dest_node_id))
1680 .map_or(0, |used_liquidity_msat| {
1681 available_value_contribution_msat = available_value_contribution_msat
1682 .saturating_sub(*used_liquidity_msat);
1683 *used_liquidity_msat
1686 // Verify the liquidity offered by this channel complies to the minimal contribution.
1687 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1688 // Do not consider candidate hops that would exceed the maximum path length.
1689 let path_length_to_node = $next_hops_path_length + 1;
1690 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1692 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1693 // In order to already account for some of the privacy enhancing random CLTV
1694 // expiry delta offset we add on top later, we subtract a rough estimate
1695 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1696 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1697 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1698 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1699 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1700 .saturating_add($candidate.cltv_expiry_delta());
1701 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1703 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1704 // Includes paying fees for the use of the following channels.
1705 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1706 Some(result) => result,
1707 // Can't overflow due to how the values were computed right above.
1708 None => unreachable!(),
1710 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1711 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1712 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1714 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1715 let may_overpay_to_meet_path_minimum_msat =
1716 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1717 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1718 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1719 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1721 let payment_failed_on_this_channel = scid_opt.map_or(false,
1722 |scid| payment_params.previously_failed_channels.contains(&scid));
1724 let should_log_candidate = match $candidate {
1725 CandidateRouteHop::FirstHop { .. } => true,
1726 CandidateRouteHop::PrivateHop { .. } => true,
1727 CandidateRouteHop::Blinded { .. } => true,
1731 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1732 // bother considering this channel. If retrying with recommended_value_msat may
1733 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1734 // around again with a higher amount.
1735 if !contributes_sufficient_value {
1736 if should_log_candidate {
1737 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1739 num_ignored_value_contribution += 1;
1740 } else if exceeds_max_path_length {
1741 if should_log_candidate {
1742 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1744 num_ignored_path_length_limit += 1;
1745 } else if exceeds_cltv_delta_limit {
1746 if should_log_candidate {
1747 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1749 num_ignored_cltv_delta_limit += 1;
1750 } else if payment_failed_on_this_channel {
1751 if should_log_candidate {
1752 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1754 num_ignored_previously_failed += 1;
1755 } else if may_overpay_to_meet_path_minimum_msat {
1756 hit_minimum_limit = true;
1757 } else if over_path_minimum_msat {
1758 // Note that low contribution here (limited by available_liquidity_msat)
1759 // might violate htlc_minimum_msat on the hops which are next along the
1760 // payment path (upstream to the payee). To avoid that, we recompute
1761 // path fees knowing the final path contribution after constructing it.
1762 let path_htlc_minimum_msat = cmp::max(
1763 compute_fees_saturating($next_hops_path_htlc_minimum_msat, $candidate.fees())
1764 .saturating_add($next_hops_path_htlc_minimum_msat),
1765 $candidate.htlc_minimum_msat());
1766 let hm_entry = dist.entry($src_node_id);
1767 let old_entry = hm_entry.or_insert_with(|| {
1768 // If there was previously no known way to access the source node
1769 // (recall it goes payee-to-payer) of short_channel_id, first add a
1770 // semi-dummy record just to compute the fees to reach the source node.
1771 // This will affect our decision on selecting short_channel_id
1772 // as a way to reach the $dest_node_id.
1774 node_id: $dest_node_id.clone(),
1775 candidate: $candidate.clone(),
1777 next_hops_fee_msat: u64::max_value(),
1778 hop_use_fee_msat: u64::max_value(),
1779 total_fee_msat: u64::max_value(),
1780 path_htlc_minimum_msat,
1781 path_penalty_msat: u64::max_value(),
1782 was_processed: false,
1783 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1784 value_contribution_msat,
1788 #[allow(unused_mut)] // We only use the mut in cfg(test)
1789 let mut should_process = !old_entry.was_processed;
1790 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1792 // In test/fuzzing builds, we do extra checks to make sure the skipping
1793 // of already-seen nodes only happens in cases we expect (see below).
1794 if !should_process { should_process = true; }
1798 let mut hop_use_fee_msat = 0;
1799 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1801 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1802 // will have the same effective-fee
1803 if $src_node_id != our_node_id {
1804 // Note that `u64::max_value` means we'll always fail the
1805 // `old_entry.total_fee_msat > total_fee_msat` check below
1806 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1807 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1810 let channel_usage = ChannelUsage {
1811 amount_msat: amount_to_transfer_over_msat,
1812 inflight_htlc_msat: used_liquidity_msat,
1815 let channel_penalty_msat = scid_opt.map_or(0,
1816 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1817 channel_usage, score_params));
1818 let path_penalty_msat = $next_hops_path_penalty_msat
1819 .saturating_add(channel_penalty_msat);
1820 let new_graph_node = RouteGraphNode {
1821 node_id: $src_node_id,
1822 lowest_fee_to_node: total_fee_msat,
1823 total_cltv_delta: hop_total_cltv_delta,
1824 value_contribution_msat,
1825 path_htlc_minimum_msat,
1827 path_length_to_node,
1830 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1831 // if this way is cheaper than the already known
1832 // (considering the cost to "reach" this channel from the route destination,
1833 // the cost of using this channel,
1834 // and the cost of routing to the source node of this channel).
1835 // Also, consider that htlc_minimum_msat_difference, because we might end up
1836 // paying it. Consider the following exploit:
1837 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1838 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1839 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1840 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1842 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1843 // but it may require additional tracking - we don't want to double-count
1844 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1845 // can't use something that may decrease on future hops.
1846 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1847 .saturating_add(old_entry.path_penalty_msat);
1848 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1849 .saturating_add(path_penalty_msat);
1851 if !old_entry.was_processed && new_cost < old_cost {
1852 targets.push(new_graph_node);
1853 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1854 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1855 old_entry.total_fee_msat = total_fee_msat;
1856 old_entry.node_id = $dest_node_id.clone();
1857 old_entry.candidate = $candidate.clone();
1858 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1859 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1860 old_entry.path_penalty_msat = path_penalty_msat;
1861 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1863 old_entry.value_contribution_msat = value_contribution_msat;
1865 did_add_update_path_to_src_node = Some(value_contribution_msat);
1866 } else if old_entry.was_processed && new_cost < old_cost {
1867 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1869 // If we're skipping processing a node which was previously
1870 // processed even though we found another path to it with a
1871 // cheaper fee, check that it was because the second path we
1872 // found (which we are processing now) has a lower value
1873 // contribution due to an HTLC minimum limit.
1875 // e.g. take a graph with two paths from node 1 to node 2, one
1876 // through channel A, and one through channel B. Channel A and
1877 // B are both in the to-process heap, with their scores set by
1878 // a higher htlc_minimum than fee.
1879 // Channel A is processed first, and the channels onwards from
1880 // node 1 are added to the to-process heap. Thereafter, we pop
1881 // Channel B off of the heap, note that it has a much more
1882 // restrictive htlc_maximum_msat, and recalculate the fees for
1883 // all of node 1's channels using the new, reduced, amount.
1885 // This would be bogus - we'd be selecting a higher-fee path
1886 // with a lower htlc_maximum_msat instead of the one we'd
1887 // already decided to use.
1888 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1890 value_contribution_msat + path_penalty_msat <
1891 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1899 did_add_update_path_to_src_node
1903 let default_node_features = default_node_features();
1905 // Find ways (channels with destination) to reach a given node and store them
1906 // in the corresponding data structures (routing graph etc).
1907 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1908 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1909 // This data can later be helpful to optimize routing (pay lower fees).
1910 macro_rules! add_entries_to_cheapest_to_target_node {
1911 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1912 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1913 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1914 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1915 let was_processed = elem.was_processed;
1916 elem.was_processed = true;
1919 // Entries are added to dist in add_entry!() when there is a channel from a node.
1920 // Because there are no channels from payee, it will not have a dist entry at this point.
1921 // If we're processing any other node, it is always be the result of a channel from it.
1922 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
1927 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1928 for details in first_channels {
1929 let candidate = CandidateRouteHop::FirstHop { details };
1930 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1931 $next_hops_value_contribution,
1932 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1933 $next_hops_cltv_delta, $next_hops_path_length);
1937 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1940 &default_node_features
1943 if !features.requires_unknown_bits() {
1944 for chan_id in $node.channels.iter() {
1945 let chan = network_channels.get(chan_id).unwrap();
1946 if !chan.features.requires_unknown_bits() {
1947 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1948 if first_hops.is_none() || *source != our_node_id {
1949 if directed_channel.direction().enabled {
1950 let candidate = CandidateRouteHop::PublicHop {
1951 info: directed_channel,
1952 short_channel_id: *chan_id,
1954 add_entry!(candidate, *source, $node_id,
1955 $fee_to_target_msat,
1956 $next_hops_value_contribution,
1957 $next_hops_path_htlc_minimum_msat,
1958 $next_hops_path_penalty_msat,
1959 $next_hops_cltv_delta, $next_hops_path_length);
1970 let mut payment_paths = Vec::<PaymentPath>::new();
1972 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1973 'paths_collection: loop {
1974 // For every new path, start from scratch, except for used_liquidities, which
1975 // helps to avoid reusing previously selected paths in future iterations.
1978 hit_minimum_limit = false;
1980 // If first hop is a private channel and the only way to reach the payee, this is the only
1981 // place where it could be added.
1982 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
1983 for details in first_channels {
1984 let candidate = CandidateRouteHop::FirstHop { details };
1985 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
1986 0, 0u64, 0, 0).is_some();
1987 log_trace!(logger, "{} direct route to payee via {}",
1988 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
1992 // Add the payee as a target, so that the payee-to-payer
1993 // search algorithm knows what to start with.
1994 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
1995 // The payee is not in our network graph, so nothing to add here.
1996 // There is still a chance of reaching them via last_hops though,
1997 // so don't yet fail the payment here.
1998 // If not, targets.pop() will not even let us enter the loop in step 2.
2001 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2006 // If a caller provided us with last hops, add them to routing targets. Since this happens
2007 // earlier than general path finding, they will be somewhat prioritized, although currently
2008 // it matters only if the fees are exactly the same.
2009 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2010 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2011 let have_intro_node_in_graph =
2012 // Only add the hops in this route to our candidate set if either
2013 // we have a direct channel to the first hop or the first hop is
2014 // in the regular network graph.
2015 first_hop_targets.get(&intro_node_id).is_some() ||
2016 network_nodes.get(&intro_node_id).is_some();
2017 if !have_intro_node_in_graph { continue }
2018 let candidate = if hint.1.blinded_hops.len() == 1 {
2019 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2020 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2021 let mut path_contribution_msat = path_value_msat;
2022 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2023 0, path_contribution_msat, 0, 0_u64, 0, 0)
2025 path_contribution_msat = hop_used_msat;
2027 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2028 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2030 for details in first_channels {
2031 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2032 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2036 add_entry!(first_hop_candidate, our_node_id, intro_node_id, blinded_path_fee,
2037 path_contribution_msat, candidate.htlc_minimum_msat(), 0_u64,
2038 candidate.cltv_expiry_delta(),
2039 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2043 for route in payment_params.payee.unblinded_route_hints().iter()
2044 .filter(|route| !route.0.is_empty())
2046 let first_hop_in_route = &(route.0)[0];
2047 let have_hop_src_in_graph =
2048 // Only add the hops in this route to our candidate set if either
2049 // we have a direct channel to the first hop or the first hop is
2050 // in the regular network graph.
2051 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
2052 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
2053 if have_hop_src_in_graph {
2054 // We start building the path from reverse, i.e., from payee
2055 // to the first RouteHintHop in the path.
2056 let hop_iter = route.0.iter().rev();
2057 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2058 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2059 let mut hop_used = true;
2060 let mut aggregate_next_hops_fee_msat: u64 = 0;
2061 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2062 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2063 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2064 let mut aggregate_next_hops_path_length: u8 = 0;
2065 let mut aggregate_path_contribution_msat = path_value_msat;
2067 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2068 let source = NodeId::from_pubkey(&hop.src_node_id);
2069 let target = NodeId::from_pubkey(&prev_hop_id);
2070 let candidate = network_channels
2071 .get(&hop.short_channel_id)
2072 .and_then(|channel| channel.as_directed_to(&target))
2073 .map(|(info, _)| CandidateRouteHop::PublicHop {
2075 short_channel_id: hop.short_channel_id,
2077 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2079 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2080 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2081 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2082 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2084 aggregate_path_contribution_msat = hop_used_msat;
2086 // If this hop was not used then there is no use checking the preceding
2087 // hops in the RouteHint. We can break by just searching for a direct
2088 // channel between last checked hop and first_hop_targets.
2092 let used_liquidity_msat = used_liquidities
2093 .get(&candidate.id(source < target)).copied()
2095 let channel_usage = ChannelUsage {
2096 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2097 inflight_htlc_msat: used_liquidity_msat,
2098 effective_capacity: candidate.effective_capacity(),
2100 let channel_penalty_msat = scorer.channel_penalty_msat(
2101 hop.short_channel_id, &source, &target, channel_usage, score_params
2103 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2104 .saturating_add(channel_penalty_msat);
2106 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2107 .saturating_add(hop.cltv_expiry_delta as u32);
2109 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2112 // Searching for a direct channel between last checked hop and first_hop_targets
2113 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&prev_hop_id)) {
2114 sort_first_hop_channels(first_channels, &used_liquidities,
2115 recommended_value_msat, our_node_pubkey);
2116 for details in first_channels {
2117 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2118 add_entry!(first_hop_candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
2119 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2120 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2121 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2129 // In the next values of the iterator, the aggregate fees already reflects
2130 // the sum of value sent from payer (final_value_msat) and routing fees
2131 // for the last node in the RouteHint. We need to just add the fees to
2132 // route through the current node so that the preceding node (next iteration)
2134 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2135 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2136 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2138 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
2139 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
2140 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
2141 .checked_add(hop_htlc_minimum_msat_inc);
2142 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
2144 if idx == route.0.len() - 1 {
2145 // The last hop in this iterator is the first hop in
2146 // overall RouteHint.
2147 // If this hop connects to a node with which we have a direct channel,
2148 // ignore the network graph and, if the last hop was added, add our
2149 // direct channel to the candidate set.
2151 // Note that we *must* check if the last hop was added as `add_entry`
2152 // always assumes that the third argument is a node to which we have a
2154 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2155 sort_first_hop_channels(first_channels, &used_liquidities,
2156 recommended_value_msat, our_node_pubkey);
2157 for details in first_channels {
2158 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2159 add_entry!(first_hop_candidate, our_node_id,
2160 NodeId::from_pubkey(&hop.src_node_id),
2161 aggregate_next_hops_fee_msat,
2162 aggregate_path_contribution_msat,
2163 aggregate_next_hops_path_htlc_minimum_msat,
2164 aggregate_next_hops_path_penalty_msat,
2165 aggregate_next_hops_cltv_delta,
2166 aggregate_next_hops_path_length);
2174 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2176 // At this point, targets are filled with the data from first and
2177 // last hops communicated by the caller, and the payment receiver.
2178 let mut found_new_path = false;
2181 // If this loop terminates due the exhaustion of targets, two situations are possible:
2182 // - not enough outgoing liquidity:
2183 // 0 < already_collected_value_msat < final_value_msat
2184 // - enough outgoing liquidity:
2185 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2186 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2187 // paths_collection will be stopped because found_new_path==false.
2188 // This is not necessarily a routing failure.
2189 '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() {
2191 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2192 // traversing the graph and arrange the path out of what we found.
2193 if node_id == our_node_id {
2194 let mut new_entry = dist.remove(&our_node_id).unwrap();
2195 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2198 let mut features_set = false;
2199 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2200 for details in first_channels {
2201 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2202 if details.get_outbound_payment_scid().unwrap() == scid {
2203 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2204 features_set = true;
2211 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2212 if let Some(node_info) = node.announcement_info.as_ref() {
2213 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2215 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2218 // We can fill in features for everything except hops which were
2219 // provided via the invoice we're paying. We could guess based on the
2220 // recipient's features but for now we simply avoid guessing at all.
2224 // Means we succesfully traversed from the payer to the payee, now
2225 // save this path for the payment route. Also, update the liquidity
2226 // remaining on the used hops, so that we take them into account
2227 // while looking for more paths.
2228 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2232 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2233 Some(payment_hop) => payment_hop,
2234 // We can't arrive at None because, if we ever add an entry to targets,
2235 // we also fill in the entry in dist (see add_entry!).
2236 None => unreachable!(),
2238 // We "propagate" the fees one hop backward (topologically) here,
2239 // so that fees paid for a HTLC forwarding on the current channel are
2240 // associated with the previous channel (where they will be subtracted).
2241 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2242 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2244 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2245 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2247 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2248 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2250 let mut payment_path = PaymentPath {hops: ordered_hops};
2252 // We could have possibly constructed a slightly inconsistent path: since we reduce
2253 // value being transferred along the way, we could have violated htlc_minimum_msat
2254 // on some channels we already passed (assuming dest->source direction). Here, we
2255 // recompute the fees again, so that if that's the case, we match the currently
2256 // underpaid htlc_minimum_msat with fees.
2257 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2258 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
2259 payment_path.update_value_and_recompute_fees(value_contribution_msat);
2261 // Since a path allows to transfer as much value as
2262 // the smallest channel it has ("bottleneck"), we should recompute
2263 // the fees so sender HTLC don't overpay fees when traversing
2264 // larger channels than the bottleneck. This may happen because
2265 // when we were selecting those channels we were not aware how much value
2266 // this path will transfer, and the relative fee for them
2267 // might have been computed considering a larger value.
2268 // Remember that we used these channels so that we don't rely
2269 // on the same liquidity in future paths.
2270 let mut prevented_redundant_path_selection = false;
2271 let prev_hop_iter = core::iter::once(&our_node_id)
2272 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2273 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2274 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2275 let used_liquidity_msat = used_liquidities
2276 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2277 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2278 .or_insert(spent_on_hop_msat);
2279 let hop_capacity = hop.candidate.effective_capacity();
2280 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2281 if *used_liquidity_msat == hop_max_msat {
2282 // If this path used all of this channel's available liquidity, we know
2283 // this path will not be selected again in the next loop iteration.
2284 prevented_redundant_path_selection = true;
2286 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2288 if !prevented_redundant_path_selection {
2289 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2290 // we'll probably end up picking the same path again on the next iteration.
2291 // Decrease the available liquidity of a hop in the middle of the path.
2292 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2293 let exhausted = u64::max_value();
2294 log_trace!(logger, "Disabling route candidate {} for future path building iterations to
2295 avoid duplicates.", LoggedCandidateHop(victim_candidate));
2296 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2297 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2300 // Track the total amount all our collected paths allow to send so that we know
2301 // when to stop looking for more paths
2302 already_collected_value_msat += value_contribution_msat;
2304 payment_paths.push(payment_path);
2305 found_new_path = true;
2306 break 'path_construction;
2309 // If we found a path back to the payee, we shouldn't try to process it again. This is
2310 // the equivalent of the `elem.was_processed` check in
2311 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2312 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2314 // Otherwise, since the current target node is not us,
2315 // keep "unrolling" the payment graph from payee to payer by
2316 // finding a way to reach the current target from the payer side.
2317 match network_nodes.get(&node_id) {
2320 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2321 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2322 total_cltv_delta, path_length_to_node);
2328 if !found_new_path && channel_saturation_pow_half != 0 {
2329 channel_saturation_pow_half = 0;
2330 continue 'paths_collection;
2332 // If we don't support MPP, no use trying to gather more value ever.
2333 break 'paths_collection;
2337 // Stop either when the recommended value is reached or if no new path was found in this
2339 // In the latter case, making another path finding attempt won't help,
2340 // because we deterministically terminated the search due to low liquidity.
2341 if !found_new_path && channel_saturation_pow_half != 0 {
2342 channel_saturation_pow_half = 0;
2343 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2344 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2345 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2346 break 'paths_collection;
2347 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2348 // Further, if this was our first walk of the graph, and we weren't limited by an
2349 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2350 // limited by an htlc_minimum_msat value, find another path with a higher value,
2351 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2352 // still keeping a lower total fee than this path.
2353 if !hit_minimum_limit {
2354 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2355 break 'paths_collection;
2357 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
2358 path_value_msat = recommended_value_msat;
2362 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2363 num_ignored_cltv_delta_limit + num_ignored_previously_failed;
2364 if num_ignored_total > 0 {
2365 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);
2369 if payment_paths.len() == 0 {
2370 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2373 if already_collected_value_msat < final_value_msat {
2374 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2378 let mut selected_route = payment_paths;
2380 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2381 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2383 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2384 // the value they contribute towards the payment amount.
2385 // We sort in descending order as we will remove from the front in `retain`, next.
2386 selected_route.sort_unstable_by(|a, b|
2387 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2388 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2391 // We should make sure that at least 1 path left.
2392 let mut paths_left = selected_route.len();
2393 selected_route.retain(|path| {
2394 if paths_left == 1 {
2397 let path_value_msat = path.get_value_msat();
2398 if path_value_msat <= overpaid_value_msat {
2399 overpaid_value_msat -= path_value_msat;
2405 debug_assert!(selected_route.len() > 0);
2407 if overpaid_value_msat != 0 {
2409 // Now, subtract the remaining overpaid value from the most-expensive path.
2410 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2411 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2412 selected_route.sort_unstable_by(|a, b| {
2413 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2414 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2415 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2417 let expensive_payment_path = selected_route.first_mut().unwrap();
2419 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2420 // can't go negative.
2421 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2422 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2426 // Sort by the path itself and combine redundant paths.
2427 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2428 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2430 selected_route.sort_unstable_by_key(|path| {
2431 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2432 debug_assert!(path.hops.len() <= key.len());
2433 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2438 for idx in 0..(selected_route.len() - 1) {
2439 if idx + 1 >= selected_route.len() { break; }
2440 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2441 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2442 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2443 selected_route[idx].update_value_and_recompute_fees(new_value);
2444 selected_route.remove(idx + 1);
2448 let mut paths = Vec::new();
2449 for payment_path in selected_route {
2450 let mut hops = Vec::with_capacity(payment_path.hops.len());
2451 for (hop, node_features) in payment_path.hops.iter()
2452 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2454 hops.push(RouteHop {
2455 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)})?,
2456 node_features: node_features.clone(),
2457 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2458 channel_features: hop.candidate.features(),
2459 fee_msat: hop.fee_msat,
2460 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2463 let mut final_cltv_delta = final_cltv_expiry_delta;
2464 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2465 if let Some(blinded_path) = h.candidate.blinded_path() {
2466 final_cltv_delta = h.candidate.cltv_expiry_delta();
2468 hops: blinded_path.blinded_hops.clone(),
2469 blinding_point: blinded_path.blinding_point,
2470 excess_final_cltv_expiry_delta: 0,
2471 final_value_msat: h.fee_msat,
2475 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2476 // applicable for the previous hop.
2477 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2478 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2481 paths.push(Path { hops, blinded_tail });
2483 // Make sure we would never create a route with more paths than we allow.
2484 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2486 if let Some(node_features) = payment_params.payee.node_features() {
2487 for path in paths.iter_mut() {
2488 path.hops.last_mut().unwrap().node_features = node_features.clone();
2492 let route = Route { paths, payment_params: Some(payment_params.clone()) };
2493 log_info!(logger, "Got route: {}", log_route!(route));
2497 // When an adversarial intermediary node observes a payment, it may be able to infer its
2498 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2499 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2500 // payment path by adding a randomized 'shadow route' offset to the final hop.
2501 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2502 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2504 let network_channels = network_graph.channels();
2505 let network_nodes = network_graph.nodes();
2507 for path in route.paths.iter_mut() {
2508 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2510 // Remember the last three nodes of the random walk and avoid looping back on them.
2511 // Init with the last three nodes from the actual path, if possible.
2512 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2513 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2514 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2516 // Choose the last publicly known node as the starting point for the random walk.
2517 let mut cur_hop: Option<NodeId> = None;
2518 let mut path_nonce = [0u8; 12];
2519 if let Some(starting_hop) = path.hops.iter().rev()
2520 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2521 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2522 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2525 // Init PRNG with the path-dependant nonce, which is static for private paths.
2526 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2527 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2529 // Pick a random path length in [1 .. 3]
2530 prng.process_in_place(&mut random_path_bytes);
2531 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2533 for random_hop in 0..random_walk_length {
2534 // If we don't find a suitable offset in the public network graph, we default to
2535 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2536 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2538 if let Some(cur_node_id) = cur_hop {
2539 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2540 // Randomly choose the next unvisited hop.
2541 prng.process_in_place(&mut random_path_bytes);
2542 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2543 .checked_rem(cur_node.channels.len())
2544 .and_then(|index| cur_node.channels.get(index))
2545 .and_then(|id| network_channels.get(id)) {
2546 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2547 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2548 nodes_to_avoid[random_hop] = *next_id;
2549 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2550 cur_hop = Some(*next_id);
2557 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2558 .checked_add(random_hop_offset)
2559 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2562 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2563 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2564 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2566 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2567 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2568 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2569 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2570 max_path_offset = cmp::max(
2571 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2572 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2573 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2575 // Add 'shadow' CLTV offset to the final hop
2576 if let Some(tail) = path.blinded_tail.as_mut() {
2577 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2578 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2580 if let Some(last_hop) = path.hops.last_mut() {
2581 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2582 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2587 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2588 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2590 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2591 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2592 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2593 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2594 ) -> Result<Route, LightningError>
2595 where L::Target: Logger, GL::Target: Logger {
2596 let graph_lock = network_graph.read_only();
2597 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2598 &graph_lock, logger, random_seed_bytes)?;
2599 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2603 fn build_route_from_hops_internal<L: Deref>(
2604 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2605 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2606 ) -> Result<Route, LightningError> where L::Target: Logger {
2609 our_node_id: NodeId,
2610 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2613 impl ScoreLookUp for HopScorer {
2614 type ScoreParams = ();
2615 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2616 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2618 let mut cur_id = self.our_node_id;
2619 for i in 0..self.hop_ids.len() {
2620 if let Some(next_id) = self.hop_ids[i] {
2621 if cur_id == *source && next_id == *target {
2633 impl<'a> Writeable for HopScorer {
2635 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2640 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2641 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2644 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2645 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2646 for i in 0..hops.len() {
2647 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2650 let scorer = HopScorer { our_node_id, hop_ids };
2652 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &(), random_seed_bytes)
2657 use crate::blinded_path::{BlindedHop, BlindedPath};
2658 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2659 use crate::routing::utxo::UtxoResult;
2660 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2661 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2662 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2663 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2664 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2665 use crate::chain::transaction::OutPoint;
2666 use crate::sign::EntropySource;
2667 use crate::ln::ChannelId;
2668 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2669 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2670 use crate::ln::channelmanager;
2671 use crate::offers::invoice::BlindedPayInfo;
2672 use crate::util::config::UserConfig;
2673 use crate::util::test_utils as ln_test_utils;
2674 use crate::util::chacha20::ChaCha20;
2675 use crate::util::ser::{Readable, Writeable};
2677 use crate::util::ser::Writer;
2679 use bitcoin::hashes::Hash;
2680 use bitcoin::network::constants::Network;
2681 use bitcoin::blockdata::constants::genesis_block;
2682 use bitcoin::blockdata::script::Builder;
2683 use bitcoin::blockdata::opcodes;
2684 use bitcoin::blockdata::transaction::TxOut;
2688 use bitcoin::secp256k1::{PublicKey,SecretKey};
2689 use bitcoin::secp256k1::Secp256k1;
2691 use crate::io::Cursor;
2692 use crate::prelude::*;
2693 use crate::sync::Arc;
2695 use core::convert::TryInto;
2697 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2698 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2699 channelmanager::ChannelDetails {
2700 channel_id: ChannelId::new_zero(),
2701 counterparty: channelmanager::ChannelCounterparty {
2704 unspendable_punishment_reserve: 0,
2705 forwarding_info: None,
2706 outbound_htlc_minimum_msat: None,
2707 outbound_htlc_maximum_msat: None,
2709 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2712 outbound_scid_alias: None,
2713 inbound_scid_alias: None,
2714 channel_value_satoshis: 0,
2716 outbound_capacity_msat,
2717 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2718 next_outbound_htlc_minimum_msat: 0,
2719 inbound_capacity_msat: 42,
2720 unspendable_punishment_reserve: None,
2721 confirmations_required: None,
2722 confirmations: None,
2723 force_close_spend_delay: None,
2724 is_outbound: true, is_channel_ready: true,
2725 is_usable: true, is_public: true,
2726 inbound_htlc_minimum_msat: None,
2727 inbound_htlc_maximum_msat: None,
2729 feerate_sat_per_1000_weight: None,
2730 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2735 fn simple_route_test() {
2736 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2737 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2738 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2739 let scorer = ln_test_utils::TestScorer::new();
2740 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2741 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2743 // Simple route to 2 via 1
2745 let route_params = RouteParameters::from_payment_params_and_value(
2746 payment_params.clone(), 0);
2747 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2748 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
2749 &random_seed_bytes) {
2750 assert_eq!(err, "Cannot send a payment of 0 msat");
2751 } else { panic!(); }
2753 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2754 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2755 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2756 assert_eq!(route.paths[0].hops.len(), 2);
2758 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2759 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2760 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2761 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2762 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2763 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2765 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2766 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2767 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2768 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2769 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2770 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2774 fn invalid_first_hop_test() {
2775 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2776 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2777 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2778 let scorer = ln_test_utils::TestScorer::new();
2779 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2780 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2782 // Simple route to 2 via 1
2784 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2786 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2787 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2788 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2789 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2790 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2791 } else { panic!(); }
2793 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2794 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2795 assert_eq!(route.paths[0].hops.len(), 2);
2799 fn htlc_minimum_test() {
2800 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2801 let (our_privkey, our_id, privkeys, 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 // Disable other paths
2810 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2811 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2812 short_channel_id: 12,
2814 flags: 2, // to disable
2815 cltv_expiry_delta: 0,
2816 htlc_minimum_msat: 0,
2817 htlc_maximum_msat: MAX_VALUE_MSAT,
2819 fee_proportional_millionths: 0,
2820 excess_data: Vec::new()
2822 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2824 short_channel_id: 3,
2826 flags: 2, // to disable
2827 cltv_expiry_delta: 0,
2828 htlc_minimum_msat: 0,
2829 htlc_maximum_msat: MAX_VALUE_MSAT,
2831 fee_proportional_millionths: 0,
2832 excess_data: Vec::new()
2834 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2836 short_channel_id: 13,
2838 flags: 2, // to disable
2839 cltv_expiry_delta: 0,
2840 htlc_minimum_msat: 0,
2841 htlc_maximum_msat: MAX_VALUE_MSAT,
2843 fee_proportional_millionths: 0,
2844 excess_data: Vec::new()
2846 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2848 short_channel_id: 6,
2850 flags: 2, // to disable
2851 cltv_expiry_delta: 0,
2852 htlc_minimum_msat: 0,
2853 htlc_maximum_msat: MAX_VALUE_MSAT,
2855 fee_proportional_millionths: 0,
2856 excess_data: Vec::new()
2858 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2860 short_channel_id: 7,
2862 flags: 2, // to disable
2863 cltv_expiry_delta: 0,
2864 htlc_minimum_msat: 0,
2865 htlc_maximum_msat: MAX_VALUE_MSAT,
2867 fee_proportional_millionths: 0,
2868 excess_data: Vec::new()
2871 // Check against amount_to_transfer_over_msat.
2872 // Set minimal HTLC of 200_000_000 msat.
2873 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2874 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2875 short_channel_id: 2,
2878 cltv_expiry_delta: 0,
2879 htlc_minimum_msat: 200_000_000,
2880 htlc_maximum_msat: MAX_VALUE_MSAT,
2882 fee_proportional_millionths: 0,
2883 excess_data: Vec::new()
2886 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2888 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2889 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2890 short_channel_id: 4,
2893 cltv_expiry_delta: 0,
2894 htlc_minimum_msat: 0,
2895 htlc_maximum_msat: 199_999_999,
2897 fee_proportional_millionths: 0,
2898 excess_data: Vec::new()
2901 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2902 let route_params = RouteParameters::from_payment_params_and_value(
2903 payment_params, 199_999_999);
2904 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2905 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
2906 &random_seed_bytes) {
2907 assert_eq!(err, "Failed to find a path to the given destination");
2908 } else { panic!(); }
2910 // Lift the restriction on the first hop.
2911 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2912 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2913 short_channel_id: 2,
2916 cltv_expiry_delta: 0,
2917 htlc_minimum_msat: 0,
2918 htlc_maximum_msat: MAX_VALUE_MSAT,
2920 fee_proportional_millionths: 0,
2921 excess_data: Vec::new()
2924 // A payment above the minimum should pass
2925 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2926 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2927 assert_eq!(route.paths[0].hops.len(), 2);
2931 fn htlc_minimum_overpay_test() {
2932 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2933 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2934 let config = UserConfig::default();
2935 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
2936 let scorer = ln_test_utils::TestScorer::new();
2937 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2938 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2940 // A route to node#2 via two paths.
2941 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2942 // Thus, they can't send 60 without overpaying.
2943 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2944 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2945 short_channel_id: 2,
2948 cltv_expiry_delta: 0,
2949 htlc_minimum_msat: 35_000,
2950 htlc_maximum_msat: 40_000,
2952 fee_proportional_millionths: 0,
2953 excess_data: Vec::new()
2955 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2956 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2957 short_channel_id: 12,
2960 cltv_expiry_delta: 0,
2961 htlc_minimum_msat: 35_000,
2962 htlc_maximum_msat: 40_000,
2964 fee_proportional_millionths: 0,
2965 excess_data: Vec::new()
2969 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2970 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2971 short_channel_id: 13,
2974 cltv_expiry_delta: 0,
2975 htlc_minimum_msat: 0,
2976 htlc_maximum_msat: MAX_VALUE_MSAT,
2978 fee_proportional_millionths: 0,
2979 excess_data: Vec::new()
2981 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2982 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2983 short_channel_id: 4,
2986 cltv_expiry_delta: 0,
2987 htlc_minimum_msat: 0,
2988 htlc_maximum_msat: MAX_VALUE_MSAT,
2990 fee_proportional_millionths: 0,
2991 excess_data: Vec::new()
2994 // Disable other paths
2995 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2996 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2997 short_channel_id: 1,
2999 flags: 2, // to disable
3000 cltv_expiry_delta: 0,
3001 htlc_minimum_msat: 0,
3002 htlc_maximum_msat: MAX_VALUE_MSAT,
3004 fee_proportional_millionths: 0,
3005 excess_data: Vec::new()
3008 let route_params = RouteParameters::from_payment_params_and_value(
3009 payment_params.clone(), 60_000);
3010 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3011 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3012 // Overpay fees to hit htlc_minimum_msat.
3013 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3014 // TODO: this could be better balanced to overpay 10k and not 15k.
3015 assert_eq!(overpaid_fees, 15_000);
3017 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3018 // while taking even more fee to match htlc_minimum_msat.
3019 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3020 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3021 short_channel_id: 12,
3024 cltv_expiry_delta: 0,
3025 htlc_minimum_msat: 65_000,
3026 htlc_maximum_msat: 80_000,
3028 fee_proportional_millionths: 0,
3029 excess_data: Vec::new()
3031 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3032 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3033 short_channel_id: 2,
3036 cltv_expiry_delta: 0,
3037 htlc_minimum_msat: 0,
3038 htlc_maximum_msat: MAX_VALUE_MSAT,
3040 fee_proportional_millionths: 0,
3041 excess_data: Vec::new()
3043 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3044 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3045 short_channel_id: 4,
3048 cltv_expiry_delta: 0,
3049 htlc_minimum_msat: 0,
3050 htlc_maximum_msat: MAX_VALUE_MSAT,
3052 fee_proportional_millionths: 100_000,
3053 excess_data: Vec::new()
3056 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3057 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3058 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3059 assert_eq!(route.paths.len(), 1);
3060 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3061 let fees = route.paths[0].hops[0].fee_msat;
3062 assert_eq!(fees, 5_000);
3064 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3065 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3066 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3067 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3068 // the other channel.
3069 assert_eq!(route.paths.len(), 1);
3070 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3071 let fees = route.paths[0].hops[0].fee_msat;
3072 assert_eq!(fees, 5_000);
3076 fn disable_channels_test() {
3077 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3078 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3079 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3080 let scorer = ln_test_utils::TestScorer::new();
3081 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3082 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3084 // // Disable channels 4 and 12 by flags=2
3085 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3086 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3087 short_channel_id: 4,
3089 flags: 2, // to disable
3090 cltv_expiry_delta: 0,
3091 htlc_minimum_msat: 0,
3092 htlc_maximum_msat: MAX_VALUE_MSAT,
3094 fee_proportional_millionths: 0,
3095 excess_data: Vec::new()
3097 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3098 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3099 short_channel_id: 12,
3101 flags: 2, // to disable
3102 cltv_expiry_delta: 0,
3103 htlc_minimum_msat: 0,
3104 htlc_maximum_msat: MAX_VALUE_MSAT,
3106 fee_proportional_millionths: 0,
3107 excess_data: Vec::new()
3110 // If all the channels require some features we don't understand, route should fail
3111 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3112 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3113 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3114 &random_seed_bytes) {
3115 assert_eq!(err, "Failed to find a path to the given destination");
3116 } else { panic!(); }
3118 // If we specify a channel to node7, that overrides our local channel view and that gets used
3119 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3120 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3121 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3122 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3123 &random_seed_bytes).unwrap();
3124 assert_eq!(route.paths[0].hops.len(), 2);
3126 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3127 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3128 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3129 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3130 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3131 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3133 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3134 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3135 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3136 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3137 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3138 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3142 fn disable_node_test() {
3143 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3144 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3145 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3146 let scorer = ln_test_utils::TestScorer::new();
3147 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3148 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3150 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3151 let mut unknown_features = NodeFeatures::empty();
3152 unknown_features.set_unknown_feature_required();
3153 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3154 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3155 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3157 // If all nodes require some features we don't understand, route should fail
3158 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3159 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3160 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3161 &random_seed_bytes) {
3162 assert_eq!(err, "Failed to find a path to the given destination");
3163 } else { panic!(); }
3165 // If we specify a channel to node7, that overrides our local channel view and that gets used
3166 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3167 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3168 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3169 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3170 &random_seed_bytes).unwrap();
3171 assert_eq!(route.paths[0].hops.len(), 2);
3173 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3174 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3175 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3176 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3177 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3178 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3180 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3181 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3182 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3183 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3184 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3185 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3187 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3188 // naively) assume that the user checked the feature bits on the invoice, which override
3189 // the node_announcement.
3193 fn our_chans_test() {
3194 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3195 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3196 let scorer = ln_test_utils::TestScorer::new();
3197 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3198 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3200 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3201 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3202 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3203 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3204 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3205 assert_eq!(route.paths[0].hops.len(), 3);
3207 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3208 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3209 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3210 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3211 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3212 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3214 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3215 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3216 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3217 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3218 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3219 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3221 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3222 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3223 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3224 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3225 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3226 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3228 // If we specify a channel to node7, that overrides our local channel view and that gets used
3229 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3230 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3231 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3232 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3233 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3234 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3235 &random_seed_bytes).unwrap();
3236 assert_eq!(route.paths[0].hops.len(), 2);
3238 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3239 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3240 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3241 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3242 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3243 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3245 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3246 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3247 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3248 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3249 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3250 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3253 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3254 let zero_fees = RoutingFees {
3256 proportional_millionths: 0,
3258 vec![RouteHint(vec![RouteHintHop {
3259 src_node_id: nodes[3],
3260 short_channel_id: 8,
3262 cltv_expiry_delta: (8 << 4) | 1,
3263 htlc_minimum_msat: None,
3264 htlc_maximum_msat: None,
3266 ]), RouteHint(vec![RouteHintHop {
3267 src_node_id: nodes[4],
3268 short_channel_id: 9,
3271 proportional_millionths: 0,
3273 cltv_expiry_delta: (9 << 4) | 1,
3274 htlc_minimum_msat: None,
3275 htlc_maximum_msat: None,
3276 }]), RouteHint(vec![RouteHintHop {
3277 src_node_id: nodes[5],
3278 short_channel_id: 10,
3280 cltv_expiry_delta: (10 << 4) | 1,
3281 htlc_minimum_msat: None,
3282 htlc_maximum_msat: None,
3286 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3287 let zero_fees = RoutingFees {
3289 proportional_millionths: 0,
3291 vec![RouteHint(vec![RouteHintHop {
3292 src_node_id: nodes[2],
3293 short_channel_id: 5,
3296 proportional_millionths: 0,
3298 cltv_expiry_delta: (5 << 4) | 1,
3299 htlc_minimum_msat: None,
3300 htlc_maximum_msat: None,
3302 src_node_id: nodes[3],
3303 short_channel_id: 8,
3305 cltv_expiry_delta: (8 << 4) | 1,
3306 htlc_minimum_msat: None,
3307 htlc_maximum_msat: None,
3309 ]), RouteHint(vec![RouteHintHop {
3310 src_node_id: nodes[4],
3311 short_channel_id: 9,
3314 proportional_millionths: 0,
3316 cltv_expiry_delta: (9 << 4) | 1,
3317 htlc_minimum_msat: None,
3318 htlc_maximum_msat: None,
3319 }]), RouteHint(vec![RouteHintHop {
3320 src_node_id: nodes[5],
3321 short_channel_id: 10,
3323 cltv_expiry_delta: (10 << 4) | 1,
3324 htlc_minimum_msat: None,
3325 htlc_maximum_msat: None,
3330 fn partial_route_hint_test() {
3331 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3332 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3333 let scorer = ln_test_utils::TestScorer::new();
3334 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3335 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3337 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3338 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3339 // RouteHint may be partially used by the algo to build the best path.
3341 // First check that last hop can't have its source as the payee.
3342 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3343 src_node_id: nodes[6],
3344 short_channel_id: 8,
3347 proportional_millionths: 0,
3349 cltv_expiry_delta: (8 << 4) | 1,
3350 htlc_minimum_msat: None,
3351 htlc_maximum_msat: None,
3354 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3355 invalid_last_hops.push(invalid_last_hop);
3357 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3358 .with_route_hints(invalid_last_hops).unwrap();
3359 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3360 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3361 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer, &(),
3362 &random_seed_bytes) {
3363 assert_eq!(err, "Route hint cannot have the payee as the source.");
3364 } else { panic!(); }
3367 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3368 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3369 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3370 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3371 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3372 assert_eq!(route.paths[0].hops.len(), 5);
3374 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3375 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3376 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3377 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3378 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3379 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3381 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3382 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3383 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3384 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3385 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3386 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3388 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3389 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3390 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3391 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3392 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3393 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3395 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3396 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3397 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3398 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3399 // If we have a peer in the node map, we'll use their features here since we don't have
3400 // a way of figuring out their features from the invoice:
3401 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3402 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3404 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3405 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3406 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3407 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3408 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3409 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3412 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3413 let zero_fees = RoutingFees {
3415 proportional_millionths: 0,
3417 vec![RouteHint(vec![RouteHintHop {
3418 src_node_id: nodes[3],
3419 short_channel_id: 8,
3421 cltv_expiry_delta: (8 << 4) | 1,
3422 htlc_minimum_msat: None,
3423 htlc_maximum_msat: None,
3424 }]), RouteHint(vec![
3426 ]), RouteHint(vec![RouteHintHop {
3427 src_node_id: nodes[5],
3428 short_channel_id: 10,
3430 cltv_expiry_delta: (10 << 4) | 1,
3431 htlc_minimum_msat: None,
3432 htlc_maximum_msat: None,
3437 fn ignores_empty_last_hops_test() {
3438 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3439 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3440 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3441 let scorer = ln_test_utils::TestScorer::new();
3442 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3443 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3445 // Test handling of an empty RouteHint passed in Invoice.
3446 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3447 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3448 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3449 assert_eq!(route.paths[0].hops.len(), 5);
3451 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3452 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3453 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3454 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3455 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3456 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3458 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3459 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3460 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3461 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3462 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3463 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3465 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3466 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3467 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3468 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3469 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3470 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3472 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3473 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3474 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3475 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3476 // If we have a peer in the node map, we'll use their features here since we don't have
3477 // a way of figuring out their features from the invoice:
3478 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3479 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3481 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3482 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3483 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3484 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3485 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3486 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3489 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3491 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3492 let zero_fees = RoutingFees {
3494 proportional_millionths: 0,
3496 vec![RouteHint(vec![RouteHintHop {
3497 src_node_id: hint_hops[0],
3498 short_channel_id: 0xff00,
3501 proportional_millionths: 0,
3503 cltv_expiry_delta: (5 << 4) | 1,
3504 htlc_minimum_msat: None,
3505 htlc_maximum_msat: None,
3507 src_node_id: hint_hops[1],
3508 short_channel_id: 0xff01,
3510 cltv_expiry_delta: (8 << 4) | 1,
3511 htlc_minimum_msat: None,
3512 htlc_maximum_msat: None,
3517 fn multi_hint_last_hops_test() {
3518 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3519 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3520 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3521 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3522 let scorer = ln_test_utils::TestScorer::new();
3523 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3524 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3525 // Test through channels 2, 3, 0xff00, 0xff01.
3526 // Test shows that multiple hop hints are considered.
3528 // Disabling channels 6 & 7 by flags=2
3529 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3530 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3531 short_channel_id: 6,
3533 flags: 2, // to disable
3534 cltv_expiry_delta: 0,
3535 htlc_minimum_msat: 0,
3536 htlc_maximum_msat: MAX_VALUE_MSAT,
3538 fee_proportional_millionths: 0,
3539 excess_data: Vec::new()
3541 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3542 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3543 short_channel_id: 7,
3545 flags: 2, // to disable
3546 cltv_expiry_delta: 0,
3547 htlc_minimum_msat: 0,
3548 htlc_maximum_msat: MAX_VALUE_MSAT,
3550 fee_proportional_millionths: 0,
3551 excess_data: Vec::new()
3554 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3555 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3556 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3557 assert_eq!(route.paths[0].hops.len(), 4);
3559 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3560 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3561 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3562 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3563 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3564 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3566 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3567 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3568 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3569 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3570 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3571 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3573 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3574 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3575 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3576 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3577 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3578 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3580 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3581 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3582 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3583 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3584 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3585 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3589 fn private_multi_hint_last_hops_test() {
3590 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3591 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3593 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3594 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3596 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3597 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3598 let scorer = ln_test_utils::TestScorer::new();
3599 // Test through channels 2, 3, 0xff00, 0xff01.
3600 // Test shows that multiple hop hints are considered.
3602 // Disabling channels 6 & 7 by flags=2
3603 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3604 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3605 short_channel_id: 6,
3607 flags: 2, // to disable
3608 cltv_expiry_delta: 0,
3609 htlc_minimum_msat: 0,
3610 htlc_maximum_msat: MAX_VALUE_MSAT,
3612 fee_proportional_millionths: 0,
3613 excess_data: Vec::new()
3615 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3616 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3617 short_channel_id: 7,
3619 flags: 2, // to disable
3620 cltv_expiry_delta: 0,
3621 htlc_minimum_msat: 0,
3622 htlc_maximum_msat: MAX_VALUE_MSAT,
3624 fee_proportional_millionths: 0,
3625 excess_data: Vec::new()
3628 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3629 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3630 Arc::clone(&logger), &scorer, &(), &[42u8; 32]).unwrap();
3631 assert_eq!(route.paths[0].hops.len(), 4);
3633 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3634 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3635 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3636 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3637 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3638 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3640 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3641 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3642 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3643 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3644 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3645 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3647 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3648 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3649 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3650 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3651 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3652 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3654 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3655 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3656 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3657 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3658 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3659 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3662 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3663 let zero_fees = RoutingFees {
3665 proportional_millionths: 0,
3667 vec![RouteHint(vec![RouteHintHop {
3668 src_node_id: nodes[4],
3669 short_channel_id: 11,
3671 cltv_expiry_delta: (11 << 4) | 1,
3672 htlc_minimum_msat: None,
3673 htlc_maximum_msat: None,
3675 src_node_id: nodes[3],
3676 short_channel_id: 8,
3678 cltv_expiry_delta: (8 << 4) | 1,
3679 htlc_minimum_msat: None,
3680 htlc_maximum_msat: None,
3681 }]), RouteHint(vec![RouteHintHop {
3682 src_node_id: nodes[4],
3683 short_channel_id: 9,
3686 proportional_millionths: 0,
3688 cltv_expiry_delta: (9 << 4) | 1,
3689 htlc_minimum_msat: None,
3690 htlc_maximum_msat: None,
3691 }]), RouteHint(vec![RouteHintHop {
3692 src_node_id: nodes[5],
3693 short_channel_id: 10,
3695 cltv_expiry_delta: (10 << 4) | 1,
3696 htlc_minimum_msat: None,
3697 htlc_maximum_msat: None,
3702 fn last_hops_with_public_channel_test() {
3703 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3704 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3705 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3706 let scorer = ln_test_utils::TestScorer::new();
3707 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3708 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3709 // This test shows that public routes can be present in the invoice
3710 // which would be handled in the same manner.
3712 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3713 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3714 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3715 assert_eq!(route.paths[0].hops.len(), 5);
3717 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3718 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3719 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3720 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3721 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3722 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3724 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3725 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3726 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3727 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3728 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3729 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3731 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3732 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3733 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3734 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3735 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3736 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3738 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3739 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3740 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3741 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3742 // If we have a peer in the node map, we'll use their features here since we don't have
3743 // a way of figuring out their features from the invoice:
3744 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3745 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3747 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3748 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3749 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3750 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3751 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3752 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3756 fn our_chans_last_hop_connect_test() {
3757 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3758 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3759 let scorer = ln_test_utils::TestScorer::new();
3760 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3761 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3763 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3764 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3765 let mut last_hops = last_hops(&nodes);
3766 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3767 .with_route_hints(last_hops.clone()).unwrap();
3768 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3769 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3770 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
3771 &random_seed_bytes).unwrap();
3772 assert_eq!(route.paths[0].hops.len(), 2);
3774 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3775 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3776 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3777 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3778 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3779 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3781 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3782 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3783 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3784 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3785 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3786 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3788 last_hops[0].0[0].fees.base_msat = 1000;
3790 // Revert to via 6 as the fee on 8 goes up
3791 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3792 .with_route_hints(last_hops).unwrap();
3793 let route_params = RouteParameters::from_payment_params_and_value(
3794 payment_params.clone(), 100);
3795 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3796 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3797 assert_eq!(route.paths[0].hops.len(), 4);
3799 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3800 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3801 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3802 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3803 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3804 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3806 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3807 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3808 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3809 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3810 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3811 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3813 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3814 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3815 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3816 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3817 // If we have a peer in the node map, we'll use their features here since we don't have
3818 // a way of figuring out their features from the invoice:
3819 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3820 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3822 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3823 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3824 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3825 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3826 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3827 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3829 // ...but still use 8 for larger payments as 6 has a variable feerate
3830 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
3831 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3832 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3833 assert_eq!(route.paths[0].hops.len(), 5);
3835 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3836 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3837 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3838 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3839 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3840 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3842 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3843 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3844 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3845 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3846 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3847 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3849 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3850 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3851 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3852 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3853 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3854 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3856 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3857 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3858 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
3859 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3860 // If we have a peer in the node map, we'll use their features here since we don't have
3861 // a way of figuring out their features from the invoice:
3862 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3863 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3865 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3866 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3867 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
3868 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3869 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3870 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3873 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> {
3874 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3875 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3876 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3878 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3879 let last_hops = RouteHint(vec![RouteHintHop {
3880 src_node_id: middle_node_id,
3881 short_channel_id: 8,
3884 proportional_millionths: last_hop_fee_prop,
3886 cltv_expiry_delta: (8 << 4) | 1,
3887 htlc_minimum_msat: None,
3888 htlc_maximum_msat: last_hop_htlc_max,
3890 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
3891 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3892 let scorer = ln_test_utils::TestScorer::new();
3893 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3894 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3895 let logger = ln_test_utils::TestLogger::new();
3896 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
3897 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
3898 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
3899 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &(),
3900 &random_seed_bytes);
3905 fn unannounced_path_test() {
3906 // We should be able to send a payment to a destination without any help of a routing graph
3907 // if we have a channel with a common counterparty that appears in the first and last hop
3909 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3911 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3912 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3913 assert_eq!(route.paths[0].hops.len(), 2);
3915 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
3916 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3917 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
3918 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3919 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
3920 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3922 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
3923 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3924 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
3925 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3926 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3927 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3931 fn overflow_unannounced_path_test_liquidity_underflow() {
3932 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3933 // the last-hop had a fee which overflowed a u64, we'd panic.
3934 // This was due to us adding the first-hop from us unconditionally, causing us to think
3935 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3936 // In this test, we previously hit a subtraction underflow due to having less available
3937 // liquidity at the last hop than 0.
3938 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());
3942 fn overflow_unannounced_path_test_feerate_overflow() {
3943 // This tests for the same case as above, except instead of hitting a subtraction
3944 // underflow, we hit a case where the fee charged at a hop overflowed.
3945 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());
3949 fn available_amount_while_routing_test() {
3950 // Tests whether we choose the correct available channel amount while routing.
3952 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
3953 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3954 let scorer = ln_test_utils::TestScorer::new();
3955 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3956 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3957 let config = UserConfig::default();
3958 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3960 // We will use a simple single-path route from
3961 // our node to node2 via node0: channels {1, 3}.
3963 // First disable all other paths.
3964 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3965 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3966 short_channel_id: 2,
3969 cltv_expiry_delta: 0,
3970 htlc_minimum_msat: 0,
3971 htlc_maximum_msat: 100_000,
3973 fee_proportional_millionths: 0,
3974 excess_data: Vec::new()
3976 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3977 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3978 short_channel_id: 12,
3981 cltv_expiry_delta: 0,
3982 htlc_minimum_msat: 0,
3983 htlc_maximum_msat: 100_000,
3985 fee_proportional_millionths: 0,
3986 excess_data: Vec::new()
3989 // Make the first channel (#1) very permissive,
3990 // and we will be testing all limits on the second channel.
3991 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3992 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3993 short_channel_id: 1,
3996 cltv_expiry_delta: 0,
3997 htlc_minimum_msat: 0,
3998 htlc_maximum_msat: 1_000_000_000,
4000 fee_proportional_millionths: 0,
4001 excess_data: Vec::new()
4004 // First, let's see if routing works if we have absolutely no idea about the available amount.
4005 // In this case, it should be set to 250_000 sats.
4006 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4008 short_channel_id: 3,
4011 cltv_expiry_delta: 0,
4012 htlc_minimum_msat: 0,
4013 htlc_maximum_msat: 250_000_000,
4015 fee_proportional_millionths: 0,
4016 excess_data: Vec::new()
4020 // Attempt to route more than available results in a failure.
4021 let route_params = RouteParameters::from_payment_params_and_value(
4022 payment_params.clone(), 250_000_001);
4023 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4024 &our_id, &route_params, &network_graph.read_only(), None,
4025 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4026 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4027 } else { panic!(); }
4031 // Now, attempt to route an exact amount we have should be fine.
4032 let route_params = RouteParameters::from_payment_params_and_value(
4033 payment_params.clone(), 250_000_000);
4034 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4035 Arc::clone(&logger), &scorer, &(),&random_seed_bytes).unwrap();
4036 assert_eq!(route.paths.len(), 1);
4037 let path = route.paths.last().unwrap();
4038 assert_eq!(path.hops.len(), 2);
4039 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4040 assert_eq!(path.final_value_msat(), 250_000_000);
4043 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4044 // Disable channel #1 and use another first hop.
4045 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4046 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4047 short_channel_id: 1,
4050 cltv_expiry_delta: 0,
4051 htlc_minimum_msat: 0,
4052 htlc_maximum_msat: 1_000_000_000,
4054 fee_proportional_millionths: 0,
4055 excess_data: Vec::new()
4058 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4059 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4062 // Attempt to route more than available results in a failure.
4063 let route_params = RouteParameters::from_payment_params_and_value(
4064 payment_params.clone(), 200_000_001);
4065 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4066 &our_id, &route_params, &network_graph.read_only(),
4067 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4068 &(), &random_seed_bytes) {
4069 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4070 } else { panic!(); }
4074 // Now, attempt to route an exact amount we have should be fine.
4075 let route_params = RouteParameters::from_payment_params_and_value(
4076 payment_params.clone(), 200_000_000);
4077 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4078 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
4079 &random_seed_bytes).unwrap();
4080 assert_eq!(route.paths.len(), 1);
4081 let path = route.paths.last().unwrap();
4082 assert_eq!(path.hops.len(), 2);
4083 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4084 assert_eq!(path.final_value_msat(), 200_000_000);
4087 // Enable channel #1 back.
4088 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4089 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4090 short_channel_id: 1,
4093 cltv_expiry_delta: 0,
4094 htlc_minimum_msat: 0,
4095 htlc_maximum_msat: 1_000_000_000,
4097 fee_proportional_millionths: 0,
4098 excess_data: Vec::new()
4102 // Now let's see if routing works if we know only htlc_maximum_msat.
4103 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4104 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4105 short_channel_id: 3,
4108 cltv_expiry_delta: 0,
4109 htlc_minimum_msat: 0,
4110 htlc_maximum_msat: 15_000,
4112 fee_proportional_millionths: 0,
4113 excess_data: Vec::new()
4117 // Attempt to route more than available results in a failure.
4118 let route_params = RouteParameters::from_payment_params_and_value(
4119 payment_params.clone(), 15_001);
4120 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4121 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4122 &scorer, &(), &random_seed_bytes) {
4123 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4124 } else { panic!(); }
4128 // Now, attempt to route an exact amount we have should be fine.
4129 let route_params = RouteParameters::from_payment_params_and_value(
4130 payment_params.clone(), 15_000);
4131 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4132 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4133 assert_eq!(route.paths.len(), 1);
4134 let path = route.paths.last().unwrap();
4135 assert_eq!(path.hops.len(), 2);
4136 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4137 assert_eq!(path.final_value_msat(), 15_000);
4140 // Now let's see if routing works if we know only capacity from the UTXO.
4142 // We can't change UTXO capacity on the fly, so we'll disable
4143 // the existing channel and add another one with the capacity we need.
4144 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4145 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4146 short_channel_id: 3,
4149 cltv_expiry_delta: 0,
4150 htlc_minimum_msat: 0,
4151 htlc_maximum_msat: MAX_VALUE_MSAT,
4153 fee_proportional_millionths: 0,
4154 excess_data: Vec::new()
4157 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4158 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4159 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4160 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4161 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4163 *chain_monitor.utxo_ret.lock().unwrap() =
4164 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4165 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4167 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4168 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4169 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4170 short_channel_id: 333,
4173 cltv_expiry_delta: (3 << 4) | 1,
4174 htlc_minimum_msat: 0,
4175 htlc_maximum_msat: 15_000,
4177 fee_proportional_millionths: 0,
4178 excess_data: Vec::new()
4180 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4181 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4182 short_channel_id: 333,
4185 cltv_expiry_delta: (3 << 4) | 2,
4186 htlc_minimum_msat: 0,
4187 htlc_maximum_msat: 15_000,
4189 fee_proportional_millionths: 0,
4190 excess_data: Vec::new()
4194 // Attempt to route more than available results in a failure.
4195 let route_params = RouteParameters::from_payment_params_and_value(
4196 payment_params.clone(), 15_001);
4197 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4198 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4199 &scorer, &(), &random_seed_bytes) {
4200 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4201 } else { panic!(); }
4205 // Now, attempt to route an exact amount we have should be fine.
4206 let route_params = RouteParameters::from_payment_params_and_value(
4207 payment_params.clone(), 15_000);
4208 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4209 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4210 assert_eq!(route.paths.len(), 1);
4211 let path = route.paths.last().unwrap();
4212 assert_eq!(path.hops.len(), 2);
4213 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4214 assert_eq!(path.final_value_msat(), 15_000);
4217 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4218 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4219 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4220 short_channel_id: 333,
4223 cltv_expiry_delta: 0,
4224 htlc_minimum_msat: 0,
4225 htlc_maximum_msat: 10_000,
4227 fee_proportional_millionths: 0,
4228 excess_data: Vec::new()
4232 // Attempt to route more than available results in a failure.
4233 let route_params = RouteParameters::from_payment_params_and_value(
4234 payment_params.clone(), 10_001);
4235 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4236 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4237 &scorer, &(), &random_seed_bytes) {
4238 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4239 } else { panic!(); }
4243 // Now, attempt to route an exact amount we have should be fine.
4244 let route_params = RouteParameters::from_payment_params_and_value(
4245 payment_params.clone(), 10_000);
4246 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4247 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4248 assert_eq!(route.paths.len(), 1);
4249 let path = route.paths.last().unwrap();
4250 assert_eq!(path.hops.len(), 2);
4251 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4252 assert_eq!(path.final_value_msat(), 10_000);
4257 fn available_liquidity_last_hop_test() {
4258 // Check that available liquidity properly limits the path even when only
4259 // one of the latter hops is limited.
4260 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4261 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4262 let scorer = ln_test_utils::TestScorer::new();
4263 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4264 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4265 let config = UserConfig::default();
4266 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4268 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4269 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4270 // Total capacity: 50 sats.
4272 // Disable other potential paths.
4273 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4274 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4275 short_channel_id: 2,
4278 cltv_expiry_delta: 0,
4279 htlc_minimum_msat: 0,
4280 htlc_maximum_msat: 100_000,
4282 fee_proportional_millionths: 0,
4283 excess_data: Vec::new()
4285 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4286 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4287 short_channel_id: 7,
4290 cltv_expiry_delta: 0,
4291 htlc_minimum_msat: 0,
4292 htlc_maximum_msat: 100_000,
4294 fee_proportional_millionths: 0,
4295 excess_data: Vec::new()
4300 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4301 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4302 short_channel_id: 12,
4305 cltv_expiry_delta: 0,
4306 htlc_minimum_msat: 0,
4307 htlc_maximum_msat: 100_000,
4309 fee_proportional_millionths: 0,
4310 excess_data: Vec::new()
4312 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4313 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4314 short_channel_id: 13,
4317 cltv_expiry_delta: 0,
4318 htlc_minimum_msat: 0,
4319 htlc_maximum_msat: 100_000,
4321 fee_proportional_millionths: 0,
4322 excess_data: Vec::new()
4325 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4326 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4327 short_channel_id: 6,
4330 cltv_expiry_delta: 0,
4331 htlc_minimum_msat: 0,
4332 htlc_maximum_msat: 50_000,
4334 fee_proportional_millionths: 0,
4335 excess_data: Vec::new()
4337 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4338 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4339 short_channel_id: 11,
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 // Attempt to route more than available results in a failure.
4351 let route_params = RouteParameters::from_payment_params_and_value(
4352 payment_params.clone(), 60_000);
4353 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4354 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4355 &scorer, &(), &random_seed_bytes) {
4356 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4357 } else { panic!(); }
4361 // Now, attempt to route 49 sats (just a bit below the capacity).
4362 let route_params = RouteParameters::from_payment_params_and_value(
4363 payment_params.clone(), 49_000);
4364 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4365 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4366 assert_eq!(route.paths.len(), 1);
4367 let mut total_amount_paid_msat = 0;
4368 for path in &route.paths {
4369 assert_eq!(path.hops.len(), 4);
4370 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4371 total_amount_paid_msat += path.final_value_msat();
4373 assert_eq!(total_amount_paid_msat, 49_000);
4377 // Attempt to route an exact amount is also fine
4378 let route_params = RouteParameters::from_payment_params_and_value(
4379 payment_params, 50_000);
4380 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4381 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4382 assert_eq!(route.paths.len(), 1);
4383 let mut total_amount_paid_msat = 0;
4384 for path in &route.paths {
4385 assert_eq!(path.hops.len(), 4);
4386 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4387 total_amount_paid_msat += path.final_value_msat();
4389 assert_eq!(total_amount_paid_msat, 50_000);
4394 fn ignore_fee_first_hop_test() {
4395 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4396 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4397 let scorer = ln_test_utils::TestScorer::new();
4398 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4399 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4400 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4402 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4403 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4404 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4405 short_channel_id: 1,
4408 cltv_expiry_delta: 0,
4409 htlc_minimum_msat: 0,
4410 htlc_maximum_msat: 100_000,
4411 fee_base_msat: 1_000_000,
4412 fee_proportional_millionths: 0,
4413 excess_data: Vec::new()
4415 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4416 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4417 short_channel_id: 3,
4420 cltv_expiry_delta: 0,
4421 htlc_minimum_msat: 0,
4422 htlc_maximum_msat: 50_000,
4424 fee_proportional_millionths: 0,
4425 excess_data: Vec::new()
4429 let route_params = RouteParameters::from_payment_params_and_value(
4430 payment_params, 50_000);
4431 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4432 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4433 assert_eq!(route.paths.len(), 1);
4434 let mut total_amount_paid_msat = 0;
4435 for path in &route.paths {
4436 assert_eq!(path.hops.len(), 2);
4437 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4438 total_amount_paid_msat += path.final_value_msat();
4440 assert_eq!(total_amount_paid_msat, 50_000);
4445 fn simple_mpp_route_test() {
4446 let (secp_ctx, _, _, _, _) = build_graph();
4447 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4448 let config = UserConfig::default();
4449 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4450 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4451 do_simple_mpp_route_test(clear_payment_params);
4453 // MPP to a 1-hop blinded path for nodes[2]
4454 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4455 let blinded_path = BlindedPath {
4456 introduction_node_id: nodes[2],
4457 blinding_point: ln_test_utils::pubkey(42),
4458 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4460 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4462 fee_proportional_millionths: 0,
4463 htlc_minimum_msat: 0,
4464 htlc_maximum_msat: 0,
4465 cltv_expiry_delta: 0,
4466 features: BlindedHopFeatures::empty(),
4468 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4469 .with_bolt12_features(bolt12_features.clone()).unwrap();
4470 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4472 // MPP to 3 2-hop blinded paths
4473 let mut blinded_path_node_0 = blinded_path.clone();
4474 blinded_path_node_0.introduction_node_id = nodes[0];
4475 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4476 let mut node_0_payinfo = blinded_payinfo.clone();
4477 node_0_payinfo.htlc_maximum_msat = 50_000;
4479 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4480 blinded_path_node_7.introduction_node_id = nodes[7];
4481 let mut node_7_payinfo = blinded_payinfo.clone();
4482 node_7_payinfo.htlc_maximum_msat = 60_000;
4484 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4485 blinded_path_node_1.introduction_node_id = nodes[1];
4486 let mut node_1_payinfo = blinded_payinfo.clone();
4487 node_1_payinfo.htlc_maximum_msat = 180_000;
4489 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4491 (node_0_payinfo, blinded_path_node_0),
4492 (node_7_payinfo, blinded_path_node_7),
4493 (node_1_payinfo, blinded_path_node_1)
4495 .with_bolt12_features(bolt12_features).unwrap();
4496 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4500 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4501 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4502 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4503 let scorer = ln_test_utils::TestScorer::new();
4504 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4505 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4507 // We need a route consisting of 3 paths:
4508 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4509 // To achieve this, the amount being transferred should be around
4510 // the total capacity of these 3 paths.
4512 // First, we set limits on these (previously unlimited) channels.
4513 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4515 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4516 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4517 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4518 short_channel_id: 1,
4521 cltv_expiry_delta: 0,
4522 htlc_minimum_msat: 0,
4523 htlc_maximum_msat: 100_000,
4525 fee_proportional_millionths: 0,
4526 excess_data: Vec::new()
4528 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4530 short_channel_id: 3,
4533 cltv_expiry_delta: 0,
4534 htlc_minimum_msat: 0,
4535 htlc_maximum_msat: 50_000,
4537 fee_proportional_millionths: 0,
4538 excess_data: Vec::new()
4541 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4542 // (total limit 60).
4543 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4544 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4545 short_channel_id: 12,
4548 cltv_expiry_delta: 0,
4549 htlc_minimum_msat: 0,
4550 htlc_maximum_msat: 60_000,
4552 fee_proportional_millionths: 0,
4553 excess_data: Vec::new()
4555 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4556 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4557 short_channel_id: 13,
4560 cltv_expiry_delta: 0,
4561 htlc_minimum_msat: 0,
4562 htlc_maximum_msat: 60_000,
4564 fee_proportional_millionths: 0,
4565 excess_data: Vec::new()
4568 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4569 // (total capacity 180 sats).
4570 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4571 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4572 short_channel_id: 2,
4575 cltv_expiry_delta: 0,
4576 htlc_minimum_msat: 0,
4577 htlc_maximum_msat: 200_000,
4579 fee_proportional_millionths: 0,
4580 excess_data: Vec::new()
4582 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4583 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4584 short_channel_id: 4,
4587 cltv_expiry_delta: 0,
4588 htlc_minimum_msat: 0,
4589 htlc_maximum_msat: 180_000,
4591 fee_proportional_millionths: 0,
4592 excess_data: Vec::new()
4596 // Attempt to route more than available results in a failure.
4597 let route_params = RouteParameters::from_payment_params_and_value(
4598 payment_params.clone(), 300_000);
4599 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4600 &our_id, &route_params, &network_graph.read_only(), None,
4601 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4602 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4603 } else { panic!(); }
4607 // Attempt to route while setting max_path_count to 0 results in a failure.
4608 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4609 let route_params = RouteParameters::from_payment_params_and_value(
4610 zero_payment_params, 100);
4611 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4612 &our_id, &route_params, &network_graph.read_only(), None,
4613 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4614 assert_eq!(err, "Can't find a route with no paths allowed.");
4615 } else { panic!(); }
4619 // Attempt to route while setting max_path_count to 3 results in a failure.
4620 // This is the case because the minimal_value_contribution_msat would require each path
4621 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4622 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4623 let route_params = RouteParameters::from_payment_params_and_value(
4624 fail_payment_params, 250_000);
4625 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4626 &our_id, &route_params, &network_graph.read_only(), None,
4627 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4628 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4629 } else { panic!(); }
4633 // Now, attempt to route 250 sats (just a bit below the capacity).
4634 // Our algorithm should provide us with these 3 paths.
4635 let route_params = RouteParameters::from_payment_params_and_value(
4636 payment_params.clone(), 250_000);
4637 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4638 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4639 assert_eq!(route.paths.len(), 3);
4640 let mut total_amount_paid_msat = 0;
4641 for path in &route.paths {
4642 if let Some(bt) = &path.blinded_tail {
4643 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4645 assert_eq!(path.hops.len(), 2);
4646 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4648 total_amount_paid_msat += path.final_value_msat();
4650 assert_eq!(total_amount_paid_msat, 250_000);
4654 // Attempt to route an exact amount is also fine
4655 let route_params = RouteParameters::from_payment_params_and_value(
4656 payment_params.clone(), 290_000);
4657 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4658 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4659 assert_eq!(route.paths.len(), 3);
4660 let mut total_amount_paid_msat = 0;
4661 for path in &route.paths {
4662 if payment_params.payee.blinded_route_hints().len() != 0 {
4663 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4664 if let Some(bt) = &path.blinded_tail {
4665 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4666 if bt.hops.len() > 1 {
4667 assert_eq!(path.hops.last().unwrap().pubkey,
4668 payment_params.payee.blinded_route_hints().iter()
4669 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4670 .map(|(_, p)| p.introduction_node_id).unwrap());
4672 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4675 assert_eq!(path.hops.len(), 2);
4676 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4678 total_amount_paid_msat += path.final_value_msat();
4680 assert_eq!(total_amount_paid_msat, 290_000);
4685 fn long_mpp_route_test() {
4686 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4687 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4688 let scorer = ln_test_utils::TestScorer::new();
4689 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4690 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4691 let config = UserConfig::default();
4692 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4693 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4695 // We need a route consisting of 3 paths:
4696 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4697 // Note that these paths overlap (channels 5, 12, 13).
4698 // We will route 300 sats.
4699 // Each path will have 100 sats capacity, those channels which
4700 // are used twice will have 200 sats capacity.
4702 // Disable other potential paths.
4703 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4704 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4705 short_channel_id: 2,
4708 cltv_expiry_delta: 0,
4709 htlc_minimum_msat: 0,
4710 htlc_maximum_msat: 100_000,
4712 fee_proportional_millionths: 0,
4713 excess_data: Vec::new()
4715 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4716 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4717 short_channel_id: 7,
4720 cltv_expiry_delta: 0,
4721 htlc_minimum_msat: 0,
4722 htlc_maximum_msat: 100_000,
4724 fee_proportional_millionths: 0,
4725 excess_data: Vec::new()
4728 // Path via {node0, node2} is channels {1, 3, 5}.
4729 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4730 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4731 short_channel_id: 1,
4734 cltv_expiry_delta: 0,
4735 htlc_minimum_msat: 0,
4736 htlc_maximum_msat: 100_000,
4738 fee_proportional_millionths: 0,
4739 excess_data: Vec::new()
4741 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4742 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4743 short_channel_id: 3,
4746 cltv_expiry_delta: 0,
4747 htlc_minimum_msat: 0,
4748 htlc_maximum_msat: 100_000,
4750 fee_proportional_millionths: 0,
4751 excess_data: Vec::new()
4754 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4755 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4756 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4757 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4758 short_channel_id: 5,
4761 cltv_expiry_delta: 0,
4762 htlc_minimum_msat: 0,
4763 htlc_maximum_msat: 200_000,
4765 fee_proportional_millionths: 0,
4766 excess_data: Vec::new()
4769 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4770 // Add 100 sats to the capacities of {12, 13}, because these channels
4771 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4772 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4773 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4774 short_channel_id: 12,
4777 cltv_expiry_delta: 0,
4778 htlc_minimum_msat: 0,
4779 htlc_maximum_msat: 200_000,
4781 fee_proportional_millionths: 0,
4782 excess_data: Vec::new()
4784 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4785 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4786 short_channel_id: 13,
4789 cltv_expiry_delta: 0,
4790 htlc_minimum_msat: 0,
4791 htlc_maximum_msat: 200_000,
4793 fee_proportional_millionths: 0,
4794 excess_data: Vec::new()
4797 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4798 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4799 short_channel_id: 6,
4802 cltv_expiry_delta: 0,
4803 htlc_minimum_msat: 0,
4804 htlc_maximum_msat: 100_000,
4806 fee_proportional_millionths: 0,
4807 excess_data: Vec::new()
4809 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4810 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4811 short_channel_id: 11,
4814 cltv_expiry_delta: 0,
4815 htlc_minimum_msat: 0,
4816 htlc_maximum_msat: 100_000,
4818 fee_proportional_millionths: 0,
4819 excess_data: Vec::new()
4822 // Path via {node7, node2} is channels {12, 13, 5}.
4823 // We already limited them to 200 sats (they are used twice for 100 sats).
4824 // Nothing to do here.
4827 // Attempt to route more than available results in a failure.
4828 let route_params = RouteParameters::from_payment_params_and_value(
4829 payment_params.clone(), 350_000);
4830 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4831 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4832 &scorer, &(), &random_seed_bytes) {
4833 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4834 } else { panic!(); }
4838 // Now, attempt to route 300 sats (exact amount we can route).
4839 // Our algorithm should provide us with these 3 paths, 100 sats each.
4840 let route_params = RouteParameters::from_payment_params_and_value(
4841 payment_params, 300_000);
4842 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4843 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4844 assert_eq!(route.paths.len(), 3);
4846 let mut total_amount_paid_msat = 0;
4847 for path in &route.paths {
4848 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4849 total_amount_paid_msat += path.final_value_msat();
4851 assert_eq!(total_amount_paid_msat, 300_000);
4857 fn mpp_cheaper_route_test() {
4858 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4859 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4860 let scorer = ln_test_utils::TestScorer::new();
4861 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4862 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4863 let config = UserConfig::default();
4864 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4866 // This test checks that if we have two cheaper paths and one more expensive path,
4867 // so that liquidity-wise any 2 of 3 combination is sufficient,
4868 // two cheaper paths will be taken.
4869 // These paths have equal available liquidity.
4871 // We need a combination of 3 paths:
4872 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4873 // Note that these paths overlap (channels 5, 12, 13).
4874 // Each path will have 100 sats capacity, those channels which
4875 // are used twice will have 200 sats capacity.
4877 // Disable other potential paths.
4878 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4879 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4880 short_channel_id: 2,
4883 cltv_expiry_delta: 0,
4884 htlc_minimum_msat: 0,
4885 htlc_maximum_msat: 100_000,
4887 fee_proportional_millionths: 0,
4888 excess_data: Vec::new()
4890 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4891 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4892 short_channel_id: 7,
4895 cltv_expiry_delta: 0,
4896 htlc_minimum_msat: 0,
4897 htlc_maximum_msat: 100_000,
4899 fee_proportional_millionths: 0,
4900 excess_data: Vec::new()
4903 // Path via {node0, node2} is channels {1, 3, 5}.
4904 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4905 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4906 short_channel_id: 1,
4909 cltv_expiry_delta: 0,
4910 htlc_minimum_msat: 0,
4911 htlc_maximum_msat: 100_000,
4913 fee_proportional_millionths: 0,
4914 excess_data: Vec::new()
4916 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4917 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4918 short_channel_id: 3,
4921 cltv_expiry_delta: 0,
4922 htlc_minimum_msat: 0,
4923 htlc_maximum_msat: 100_000,
4925 fee_proportional_millionths: 0,
4926 excess_data: Vec::new()
4929 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4930 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4931 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4932 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4933 short_channel_id: 5,
4936 cltv_expiry_delta: 0,
4937 htlc_minimum_msat: 0,
4938 htlc_maximum_msat: 200_000,
4940 fee_proportional_millionths: 0,
4941 excess_data: Vec::new()
4944 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4945 // Add 100 sats to the capacities of {12, 13}, because these channels
4946 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4947 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4948 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4949 short_channel_id: 12,
4952 cltv_expiry_delta: 0,
4953 htlc_minimum_msat: 0,
4954 htlc_maximum_msat: 200_000,
4956 fee_proportional_millionths: 0,
4957 excess_data: Vec::new()
4959 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4960 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4961 short_channel_id: 13,
4964 cltv_expiry_delta: 0,
4965 htlc_minimum_msat: 0,
4966 htlc_maximum_msat: 200_000,
4968 fee_proportional_millionths: 0,
4969 excess_data: Vec::new()
4972 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4974 short_channel_id: 6,
4977 cltv_expiry_delta: 0,
4978 htlc_minimum_msat: 0,
4979 htlc_maximum_msat: 100_000,
4980 fee_base_msat: 1_000,
4981 fee_proportional_millionths: 0,
4982 excess_data: Vec::new()
4984 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4985 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4986 short_channel_id: 11,
4989 cltv_expiry_delta: 0,
4990 htlc_minimum_msat: 0,
4991 htlc_maximum_msat: 100_000,
4993 fee_proportional_millionths: 0,
4994 excess_data: Vec::new()
4997 // Path via {node7, node2} is channels {12, 13, 5}.
4998 // We already limited them to 200 sats (they are used twice for 100 sats).
4999 // Nothing to do here.
5002 // Now, attempt to route 180 sats.
5003 // Our algorithm should provide us with these 2 paths.
5004 let route_params = RouteParameters::from_payment_params_and_value(
5005 payment_params, 180_000);
5006 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5007 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5008 assert_eq!(route.paths.len(), 2);
5010 let mut total_value_transferred_msat = 0;
5011 let mut total_paid_msat = 0;
5012 for path in &route.paths {
5013 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5014 total_value_transferred_msat += path.final_value_msat();
5015 for hop in &path.hops {
5016 total_paid_msat += hop.fee_msat;
5019 // If we paid fee, this would be higher.
5020 assert_eq!(total_value_transferred_msat, 180_000);
5021 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5022 assert_eq!(total_fees_paid, 0);
5027 fn fees_on_mpp_route_test() {
5028 // This test makes sure that MPP algorithm properly takes into account
5029 // fees charged on the channels, by making the fees impactful:
5030 // if the fee is not properly accounted for, the behavior is different.
5031 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5032 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5033 let scorer = ln_test_utils::TestScorer::new();
5034 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5035 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5036 let config = UserConfig::default();
5037 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5039 // We need a route consisting of 2 paths:
5040 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5041 // We will route 200 sats, Each path will have 100 sats capacity.
5043 // This test is not particularly stable: e.g.,
5044 // there's a way to route via {node0, node2, node4}.
5045 // It works while pathfinding is deterministic, but can be broken otherwise.
5046 // It's fine to ignore this concern for now.
5048 // Disable other potential paths.
5049 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5050 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5051 short_channel_id: 2,
5054 cltv_expiry_delta: 0,
5055 htlc_minimum_msat: 0,
5056 htlc_maximum_msat: 100_000,
5058 fee_proportional_millionths: 0,
5059 excess_data: Vec::new()
5062 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5063 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5064 short_channel_id: 7,
5067 cltv_expiry_delta: 0,
5068 htlc_minimum_msat: 0,
5069 htlc_maximum_msat: 100_000,
5071 fee_proportional_millionths: 0,
5072 excess_data: Vec::new()
5075 // Path via {node0, node2} is channels {1, 3, 5}.
5076 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5077 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5078 short_channel_id: 1,
5081 cltv_expiry_delta: 0,
5082 htlc_minimum_msat: 0,
5083 htlc_maximum_msat: 100_000,
5085 fee_proportional_millionths: 0,
5086 excess_data: Vec::new()
5088 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5089 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5090 short_channel_id: 3,
5093 cltv_expiry_delta: 0,
5094 htlc_minimum_msat: 0,
5095 htlc_maximum_msat: 100_000,
5097 fee_proportional_millionths: 0,
5098 excess_data: Vec::new()
5101 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5102 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5103 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5104 short_channel_id: 5,
5107 cltv_expiry_delta: 0,
5108 htlc_minimum_msat: 0,
5109 htlc_maximum_msat: 100_000,
5111 fee_proportional_millionths: 0,
5112 excess_data: Vec::new()
5115 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5116 // All channels should be 100 sats capacity. But for the fee experiment,
5117 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5118 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5119 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5120 // so no matter how large are other channels,
5121 // the whole path will be limited by 100 sats with just these 2 conditions:
5122 // - channel 12 capacity is 250 sats
5123 // - fee for channel 6 is 150 sats
5124 // Let's test this by enforcing these 2 conditions and removing other limits.
5125 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5126 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5127 short_channel_id: 12,
5130 cltv_expiry_delta: 0,
5131 htlc_minimum_msat: 0,
5132 htlc_maximum_msat: 250_000,
5134 fee_proportional_millionths: 0,
5135 excess_data: Vec::new()
5137 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5138 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5139 short_channel_id: 13,
5142 cltv_expiry_delta: 0,
5143 htlc_minimum_msat: 0,
5144 htlc_maximum_msat: MAX_VALUE_MSAT,
5146 fee_proportional_millionths: 0,
5147 excess_data: Vec::new()
5150 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5151 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5152 short_channel_id: 6,
5155 cltv_expiry_delta: 0,
5156 htlc_minimum_msat: 0,
5157 htlc_maximum_msat: MAX_VALUE_MSAT,
5158 fee_base_msat: 150_000,
5159 fee_proportional_millionths: 0,
5160 excess_data: Vec::new()
5162 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5163 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5164 short_channel_id: 11,
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()
5176 // Attempt to route more than available results in a failure.
5177 let route_params = RouteParameters::from_payment_params_and_value(
5178 payment_params.clone(), 210_000);
5179 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5180 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5181 &scorer, &(), &random_seed_bytes) {
5182 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5183 } else { panic!(); }
5187 // Now, attempt to route 200 sats (exact amount we can route).
5188 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 200_000);
5189 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5190 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5191 assert_eq!(route.paths.len(), 2);
5193 let mut total_amount_paid_msat = 0;
5194 for path in &route.paths {
5195 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5196 total_amount_paid_msat += path.final_value_msat();
5198 assert_eq!(total_amount_paid_msat, 200_000);
5199 assert_eq!(route.get_total_fees(), 150_000);
5204 fn mpp_with_last_hops() {
5205 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5206 // via a single last-hop route hint, we'd fail to route if we first collected routes
5207 // totaling close but not quite enough to fund the full payment.
5209 // This was because we considered last-hop hints to have exactly the sought payment amount
5210 // instead of the amount we were trying to collect, needlessly limiting our path searching
5211 // at the very first hop.
5213 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5214 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5215 // to only have the remaining to-collect amount in available liquidity.
5217 // This bug appeared in production in some specific channel configurations.
5218 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5219 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5220 let scorer = ln_test_utils::TestScorer::new();
5221 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5222 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5223 let config = UserConfig::default();
5224 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5225 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5226 src_node_id: nodes[2],
5227 short_channel_id: 42,
5228 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5229 cltv_expiry_delta: 42,
5230 htlc_minimum_msat: None,
5231 htlc_maximum_msat: None,
5232 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5234 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5235 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5236 // would first use the no-fee route and then fail to find a path along the second route as
5237 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5238 // under 5% of our payment amount.
5239 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5240 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5241 short_channel_id: 1,
5244 cltv_expiry_delta: (5 << 4) | 5,
5245 htlc_minimum_msat: 0,
5246 htlc_maximum_msat: 99_000,
5247 fee_base_msat: u32::max_value(),
5248 fee_proportional_millionths: u32::max_value(),
5249 excess_data: Vec::new()
5251 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5252 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5253 short_channel_id: 2,
5256 cltv_expiry_delta: (5 << 4) | 3,
5257 htlc_minimum_msat: 0,
5258 htlc_maximum_msat: 99_000,
5259 fee_base_msat: u32::max_value(),
5260 fee_proportional_millionths: u32::max_value(),
5261 excess_data: Vec::new()
5263 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5265 short_channel_id: 4,
5268 cltv_expiry_delta: (4 << 4) | 1,
5269 htlc_minimum_msat: 0,
5270 htlc_maximum_msat: MAX_VALUE_MSAT,
5272 fee_proportional_millionths: 0,
5273 excess_data: Vec::new()
5275 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5276 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5277 short_channel_id: 13,
5279 flags: 0|2, // Channel disabled
5280 cltv_expiry_delta: (13 << 4) | 1,
5281 htlc_minimum_msat: 0,
5282 htlc_maximum_msat: MAX_VALUE_MSAT,
5284 fee_proportional_millionths: 2000000,
5285 excess_data: Vec::new()
5288 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5290 let route_params = RouteParameters::from_payment_params_and_value(
5291 payment_params, 100_000);
5292 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5293 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5294 assert_eq!(route.paths.len(), 2);
5295 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5296 // Paths are manually ordered ordered by SCID, so:
5297 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5298 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5299 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5300 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5301 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5302 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5303 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5304 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5305 assert_eq!(route.get_total_fees(), 1);
5306 assert_eq!(route.get_total_amount(), 100_000);
5310 fn drop_lowest_channel_mpp_route_test() {
5311 // This test checks that low-capacity channel is dropped when after
5312 // path finding we realize that we found more capacity than we need.
5313 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5314 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5315 let scorer = ln_test_utils::TestScorer::new();
5316 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5317 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5318 let config = UserConfig::default();
5319 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5320 .with_max_channel_saturation_power_of_half(0);
5322 // We need a route consisting of 3 paths:
5323 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5325 // The first and the second paths should be sufficient, but the third should be
5326 // cheaper, so that we select it but drop later.
5328 // First, we set limits on these (previously unlimited) channels.
5329 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5331 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5332 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5333 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5334 short_channel_id: 1,
5337 cltv_expiry_delta: 0,
5338 htlc_minimum_msat: 0,
5339 htlc_maximum_msat: 100_000,
5341 fee_proportional_millionths: 0,
5342 excess_data: Vec::new()
5344 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5345 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5346 short_channel_id: 3,
5349 cltv_expiry_delta: 0,
5350 htlc_minimum_msat: 0,
5351 htlc_maximum_msat: 50_000,
5353 fee_proportional_millionths: 0,
5354 excess_data: Vec::new()
5357 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5358 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5359 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5360 short_channel_id: 12,
5363 cltv_expiry_delta: 0,
5364 htlc_minimum_msat: 0,
5365 htlc_maximum_msat: 60_000,
5367 fee_proportional_millionths: 0,
5368 excess_data: Vec::new()
5370 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5371 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5372 short_channel_id: 13,
5375 cltv_expiry_delta: 0,
5376 htlc_minimum_msat: 0,
5377 htlc_maximum_msat: 60_000,
5379 fee_proportional_millionths: 0,
5380 excess_data: Vec::new()
5383 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5384 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5385 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5386 short_channel_id: 2,
5389 cltv_expiry_delta: 0,
5390 htlc_minimum_msat: 0,
5391 htlc_maximum_msat: 20_000,
5393 fee_proportional_millionths: 0,
5394 excess_data: Vec::new()
5396 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5397 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5398 short_channel_id: 4,
5401 cltv_expiry_delta: 0,
5402 htlc_minimum_msat: 0,
5403 htlc_maximum_msat: 20_000,
5405 fee_proportional_millionths: 0,
5406 excess_data: Vec::new()
5410 // Attempt to route more than available results in a failure.
5411 let route_params = RouteParameters::from_payment_params_and_value(
5412 payment_params.clone(), 150_000);
5413 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5414 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5415 &scorer, &(), &random_seed_bytes) {
5416 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5417 } else { panic!(); }
5421 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5422 // Our algorithm should provide us with these 3 paths.
5423 let route_params = RouteParameters::from_payment_params_and_value(
5424 payment_params.clone(), 125_000);
5425 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5426 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5427 assert_eq!(route.paths.len(), 3);
5428 let mut total_amount_paid_msat = 0;
5429 for path in &route.paths {
5430 assert_eq!(path.hops.len(), 2);
5431 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5432 total_amount_paid_msat += path.final_value_msat();
5434 assert_eq!(total_amount_paid_msat, 125_000);
5438 // Attempt to route without the last small cheap channel
5439 let route_params = RouteParameters::from_payment_params_and_value(
5440 payment_params, 90_000);
5441 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5442 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5443 assert_eq!(route.paths.len(), 2);
5444 let mut total_amount_paid_msat = 0;
5445 for path in &route.paths {
5446 assert_eq!(path.hops.len(), 2);
5447 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5448 total_amount_paid_msat += path.final_value_msat();
5450 assert_eq!(total_amount_paid_msat, 90_000);
5455 fn min_criteria_consistency() {
5456 // Test that we don't use an inconsistent metric between updating and walking nodes during
5457 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5458 // was updated with a different criterion from the heap sorting, resulting in loops in
5459 // calculated paths. We test for that specific case here.
5461 // We construct a network that looks like this:
5463 // node2 -1(3)2- node3
5467 // node1 -1(5)2- node4 -1(1)2- node6
5473 // We create a loop on the side of our real path - our destination is node 6, with a
5474 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5475 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5476 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5477 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5478 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5479 // "previous hop" being set to node 3, creating a loop in the path.
5480 let secp_ctx = Secp256k1::new();
5481 let logger = Arc::new(ln_test_utils::TestLogger::new());
5482 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5483 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5484 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5485 let scorer = ln_test_utils::TestScorer::new();
5486 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5487 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5488 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5490 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5491 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5492 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5493 short_channel_id: 6,
5496 cltv_expiry_delta: (6 << 4) | 0,
5497 htlc_minimum_msat: 0,
5498 htlc_maximum_msat: MAX_VALUE_MSAT,
5500 fee_proportional_millionths: 0,
5501 excess_data: Vec::new()
5503 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5505 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5506 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5507 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5508 short_channel_id: 5,
5511 cltv_expiry_delta: (5 << 4) | 0,
5512 htlc_minimum_msat: 0,
5513 htlc_maximum_msat: MAX_VALUE_MSAT,
5515 fee_proportional_millionths: 0,
5516 excess_data: Vec::new()
5518 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5520 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5521 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5522 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5523 short_channel_id: 4,
5526 cltv_expiry_delta: (4 << 4) | 0,
5527 htlc_minimum_msat: 0,
5528 htlc_maximum_msat: MAX_VALUE_MSAT,
5530 fee_proportional_millionths: 0,
5531 excess_data: Vec::new()
5533 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5535 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5536 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5537 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5538 short_channel_id: 3,
5541 cltv_expiry_delta: (3 << 4) | 0,
5542 htlc_minimum_msat: 0,
5543 htlc_maximum_msat: MAX_VALUE_MSAT,
5545 fee_proportional_millionths: 0,
5546 excess_data: Vec::new()
5548 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5550 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5551 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5552 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5553 short_channel_id: 2,
5556 cltv_expiry_delta: (2 << 4) | 0,
5557 htlc_minimum_msat: 0,
5558 htlc_maximum_msat: MAX_VALUE_MSAT,
5560 fee_proportional_millionths: 0,
5561 excess_data: Vec::new()
5564 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5565 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5566 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5567 short_channel_id: 1,
5570 cltv_expiry_delta: (1 << 4) | 0,
5571 htlc_minimum_msat: 100,
5572 htlc_maximum_msat: MAX_VALUE_MSAT,
5574 fee_proportional_millionths: 0,
5575 excess_data: Vec::new()
5577 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5580 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5581 let route_params = RouteParameters::from_payment_params_and_value(
5582 payment_params, 10_000);
5583 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5584 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5585 assert_eq!(route.paths.len(), 1);
5586 assert_eq!(route.paths[0].hops.len(), 3);
5588 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5589 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5590 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5591 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5592 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5593 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5595 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5596 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5597 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5598 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5599 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5600 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5602 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5603 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5604 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5605 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5606 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5607 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5613 fn exact_fee_liquidity_limit() {
5614 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5615 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5616 // we calculated fees on a higher value, resulting in us ignoring such paths.
5617 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5618 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5619 let scorer = ln_test_utils::TestScorer::new();
5620 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5621 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5622 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5624 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5626 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5627 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5628 short_channel_id: 2,
5631 cltv_expiry_delta: 0,
5632 htlc_minimum_msat: 0,
5633 htlc_maximum_msat: 85_000,
5635 fee_proportional_millionths: 0,
5636 excess_data: Vec::new()
5639 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5640 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5641 short_channel_id: 12,
5644 cltv_expiry_delta: (4 << 4) | 1,
5645 htlc_minimum_msat: 0,
5646 htlc_maximum_msat: 270_000,
5648 fee_proportional_millionths: 1000000,
5649 excess_data: Vec::new()
5653 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5654 // 200% fee charged channel 13 in the 1-to-2 direction.
5655 let route_params = RouteParameters::from_payment_params_and_value(
5656 payment_params, 90_000);
5657 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5658 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5659 assert_eq!(route.paths.len(), 1);
5660 assert_eq!(route.paths[0].hops.len(), 2);
5662 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5663 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5664 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5665 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5666 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5667 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5669 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5670 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5671 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5672 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5673 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5674 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5679 fn htlc_max_reduction_below_min() {
5680 // Test that if, while walking the graph, we reduce the value being sent to meet an
5681 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5682 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5683 // resulting in us thinking there is no possible path, even if other paths exist.
5684 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5685 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5686 let scorer = ln_test_utils::TestScorer::new();
5687 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5688 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5689 let config = UserConfig::default();
5690 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5692 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5693 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5694 // then try to send 90_000.
5695 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5696 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5697 short_channel_id: 2,
5700 cltv_expiry_delta: 0,
5701 htlc_minimum_msat: 0,
5702 htlc_maximum_msat: 80_000,
5704 fee_proportional_millionths: 0,
5705 excess_data: Vec::new()
5707 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5708 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5709 short_channel_id: 4,
5712 cltv_expiry_delta: (4 << 4) | 1,
5713 htlc_minimum_msat: 90_000,
5714 htlc_maximum_msat: MAX_VALUE_MSAT,
5716 fee_proportional_millionths: 0,
5717 excess_data: Vec::new()
5721 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5722 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5723 // expensive) channels 12-13 path.
5724 let route_params = RouteParameters::from_payment_params_and_value(
5725 payment_params, 90_000);
5726 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5727 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5728 assert_eq!(route.paths.len(), 1);
5729 assert_eq!(route.paths[0].hops.len(), 2);
5731 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5732 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5733 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5734 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5735 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5736 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5738 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5739 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5740 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5741 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5742 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5743 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5748 fn multiple_direct_first_hops() {
5749 // Previously we'd only ever considered one first hop path per counterparty.
5750 // However, as we don't restrict users to one channel per peer, we really need to support
5751 // looking at all first hop paths.
5752 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5753 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5754 // route over multiple channels with the same first hop.
5755 let secp_ctx = Secp256k1::new();
5756 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5757 let logger = Arc::new(ln_test_utils::TestLogger::new());
5758 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5759 let scorer = ln_test_utils::TestScorer::new();
5760 let config = UserConfig::default();
5761 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5762 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5763 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5766 let route_params = RouteParameters::from_payment_params_and_value(
5767 payment_params.clone(), 100_000);
5768 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5769 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5770 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5771 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5772 assert_eq!(route.paths.len(), 1);
5773 assert_eq!(route.paths[0].hops.len(), 1);
5775 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5776 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5777 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5780 let route_params = RouteParameters::from_payment_params_and_value(
5781 payment_params.clone(), 100_000);
5782 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5783 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5784 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5785 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5786 assert_eq!(route.paths.len(), 2);
5787 assert_eq!(route.paths[0].hops.len(), 1);
5788 assert_eq!(route.paths[1].hops.len(), 1);
5790 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5791 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5793 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5794 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5796 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5797 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5801 // If we have a bunch of outbound channels to the same node, where most are not
5802 // sufficient to pay the full payment, but one is, we should default to just using the
5803 // one single channel that has sufficient balance, avoiding MPP.
5805 // If we have several options above the 3xpayment value threshold, we should pick the
5806 // smallest of them, avoiding further fragmenting our available outbound balance to
5808 let route_params = RouteParameters::from_payment_params_and_value(
5809 payment_params, 100_000);
5810 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5811 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5812 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5813 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5814 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5815 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5816 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5817 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5818 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5819 ]), Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5820 assert_eq!(route.paths.len(), 1);
5821 assert_eq!(route.paths[0].hops.len(), 1);
5823 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5824 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5825 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5830 fn prefers_shorter_route_with_higher_fees() {
5831 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5832 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5833 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5835 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5836 let scorer = ln_test_utils::TestScorer::new();
5837 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5838 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5839 let route_params = RouteParameters::from_payment_params_and_value(
5840 payment_params.clone(), 100);
5841 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5842 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5843 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5845 assert_eq!(route.get_total_fees(), 100);
5846 assert_eq!(route.get_total_amount(), 100);
5847 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5849 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5850 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5851 let scorer = FixedPenaltyScorer::with_penalty(100);
5852 let route_params = RouteParameters::from_payment_params_and_value(
5853 payment_params, 100);
5854 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5855 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5856 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5858 assert_eq!(route.get_total_fees(), 300);
5859 assert_eq!(route.get_total_amount(), 100);
5860 assert_eq!(path, vec![2, 4, 7, 10]);
5863 struct BadChannelScorer {
5864 short_channel_id: u64,
5868 impl Writeable for BadChannelScorer {
5869 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5871 impl ScoreLookUp for BadChannelScorer {
5872 type ScoreParams = ();
5873 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5874 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5878 struct BadNodeScorer {
5883 impl Writeable for BadNodeScorer {
5884 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5887 impl ScoreLookUp for BadNodeScorer {
5888 type ScoreParams = ();
5889 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5890 if *target == self.node_id { u64::max_value() } else { 0 }
5895 fn avoids_routing_through_bad_channels_and_nodes() {
5896 let (secp_ctx, network, _, _, logger) = build_graph();
5897 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5898 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5899 let network_graph = network.read_only();
5901 // A path to nodes[6] exists when no penalties are applied to any channel.
5902 let scorer = ln_test_utils::TestScorer::new();
5903 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5904 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5905 let route_params = RouteParameters::from_payment_params_and_value(
5906 payment_params, 100);
5907 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5908 &scorer, &(), &random_seed_bytes).unwrap();
5909 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5911 assert_eq!(route.get_total_fees(), 100);
5912 assert_eq!(route.get_total_amount(), 100);
5913 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5915 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5916 let scorer = BadChannelScorer { short_channel_id: 6 };
5917 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5918 &scorer, &(), &random_seed_bytes).unwrap();
5919 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5921 assert_eq!(route.get_total_fees(), 300);
5922 assert_eq!(route.get_total_amount(), 100);
5923 assert_eq!(path, vec![2, 4, 7, 10]);
5925 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5926 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5927 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
5928 &scorer, &(), &random_seed_bytes) {
5929 Err(LightningError { err, .. } ) => {
5930 assert_eq!(err, "Failed to find a path to the given destination");
5932 Ok(_) => panic!("Expected error"),
5937 fn total_fees_single_path() {
5939 paths: vec![Path { hops: vec![
5941 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5942 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5943 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5946 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5947 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5948 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5951 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5952 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5953 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5955 ], blinded_tail: None }],
5956 payment_params: None,
5959 assert_eq!(route.get_total_fees(), 250);
5960 assert_eq!(route.get_total_amount(), 225);
5964 fn total_fees_multi_path() {
5966 paths: vec![Path { hops: vec![
5968 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5969 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5970 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5973 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5974 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5975 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5977 ], blinded_tail: None }, Path { hops: vec![
5979 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5980 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5981 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5984 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5985 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5986 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5988 ], blinded_tail: None }],
5989 payment_params: None,
5992 assert_eq!(route.get_total_fees(), 200);
5993 assert_eq!(route.get_total_amount(), 300);
5997 fn total_empty_route_no_panic() {
5998 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5999 // would both panic if the route was completely empty. We test to ensure they return 0
6000 // here, even though its somewhat nonsensical as a route.
6001 let route = Route { paths: Vec::new(), payment_params: None };
6003 assert_eq!(route.get_total_fees(), 0);
6004 assert_eq!(route.get_total_amount(), 0);
6008 fn limits_total_cltv_delta() {
6009 let (secp_ctx, network, _, _, logger) = build_graph();
6010 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6011 let network_graph = network.read_only();
6013 let scorer = ln_test_utils::TestScorer::new();
6015 // Make sure that generally there is at least one route available
6016 let feasible_max_total_cltv_delta = 1008;
6017 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6018 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6019 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6020 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6021 let route_params = RouteParameters::from_payment_params_and_value(
6022 feasible_payment_params, 100);
6023 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6024 &scorer, &(), &random_seed_bytes).unwrap();
6025 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6026 assert_ne!(path.len(), 0);
6028 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6029 let fail_max_total_cltv_delta = 23;
6030 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6031 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6032 let route_params = RouteParameters::from_payment_params_and_value(
6033 fail_payment_params, 100);
6034 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6035 &(), &random_seed_bytes)
6037 Err(LightningError { err, .. } ) => {
6038 assert_eq!(err, "Failed to find a path to the given destination");
6040 Ok(_) => panic!("Expected error"),
6045 fn avoids_recently_failed_paths() {
6046 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6047 // randomly inserting channels into it until we can't find a route anymore.
6048 let (secp_ctx, network, _, _, logger) = build_graph();
6049 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6050 let network_graph = network.read_only();
6052 let scorer = ln_test_utils::TestScorer::new();
6053 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6054 .with_max_path_count(1);
6055 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6056 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6058 // We should be able to find a route initially, and then after we fail a few random
6059 // channels eventually we won't be able to any longer.
6060 let route_params = RouteParameters::from_payment_params_and_value(
6061 payment_params.clone(), 100);
6062 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6063 &scorer, &(), &random_seed_bytes).is_ok());
6065 let route_params = RouteParameters::from_payment_params_and_value(
6066 payment_params.clone(), 100);
6067 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6068 Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
6070 for chan in route.paths[0].hops.iter() {
6071 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6073 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6074 % route.paths[0].hops.len();
6075 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6081 fn limits_path_length() {
6082 let (secp_ctx, network, _, _, logger) = build_line_graph();
6083 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6084 let network_graph = network.read_only();
6086 let scorer = ln_test_utils::TestScorer::new();
6087 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6088 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6090 // First check we can actually create a long route on this graph.
6091 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6092 let route_params = RouteParameters::from_payment_params_and_value(
6093 feasible_payment_params, 100);
6094 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6095 &scorer, &(), &random_seed_bytes).unwrap();
6096 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6097 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6099 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6100 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6101 let route_params = RouteParameters::from_payment_params_and_value(
6102 fail_payment_params, 100);
6103 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6104 &(), &random_seed_bytes)
6106 Err(LightningError { err, .. } ) => {
6107 assert_eq!(err, "Failed to find a path to the given destination");
6109 Ok(_) => panic!("Expected error"),
6114 fn adds_and_limits_cltv_offset() {
6115 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6116 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6118 let scorer = ln_test_utils::TestScorer::new();
6120 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6121 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6122 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6123 let route_params = RouteParameters::from_payment_params_and_value(
6124 payment_params.clone(), 100);
6125 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6126 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6127 assert_eq!(route.paths.len(), 1);
6129 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6131 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6132 let mut route_default = route.clone();
6133 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6134 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6135 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6136 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6137 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6139 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6140 let mut route_limited = route.clone();
6141 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6142 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6143 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6144 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6145 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6149 fn adds_plausible_cltv_offset() {
6150 let (secp_ctx, network, _, _, logger) = build_graph();
6151 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6152 let network_graph = network.read_only();
6153 let network_nodes = network_graph.nodes();
6154 let network_channels = network_graph.channels();
6155 let scorer = ln_test_utils::TestScorer::new();
6156 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6157 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6158 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6160 let route_params = RouteParameters::from_payment_params_and_value(
6161 payment_params.clone(), 100);
6162 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6163 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6164 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6166 let mut path_plausibility = vec![];
6168 for p in route.paths {
6169 // 1. Select random observation point
6170 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6171 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6173 prng.process_in_place(&mut random_bytes);
6174 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6175 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6177 // 2. Calculate what CLTV expiry delta we would observe there
6178 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6180 // 3. Starting from the observation point, find candidate paths
6181 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6182 candidates.push_back((observation_point, vec![]));
6184 let mut found_plausible_candidate = false;
6186 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6187 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6188 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6189 found_plausible_candidate = true;
6190 break 'candidate_loop;
6194 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6195 for channel_id in &cur_node.channels {
6196 if let Some(channel_info) = network_channels.get(&channel_id) {
6197 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6198 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6199 if cur_path_cltv_deltas.iter().sum::<u32>()
6200 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6201 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6202 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6203 candidates.push_back((*next_id, new_path_cltv_deltas));
6211 path_plausibility.push(found_plausible_candidate);
6213 assert!(path_plausibility.iter().all(|x| *x));
6217 fn builds_correct_path_from_hops() {
6218 let (secp_ctx, network, _, _, logger) = build_graph();
6219 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6220 let network_graph = network.read_only();
6222 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6223 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6225 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6226 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6227 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6228 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6229 Arc::clone(&logger), &random_seed_bytes).unwrap();
6230 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6231 assert_eq!(hops.len(), route.paths[0].hops.len());
6232 for (idx, hop_pubkey) in hops.iter().enumerate() {
6233 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6238 fn avoids_saturating_channels() {
6239 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6240 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6241 let decay_params = ProbabilisticScoringDecayParameters::default();
6242 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6244 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6245 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6246 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6247 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6248 short_channel_id: 4,
6251 cltv_expiry_delta: (4 << 4) | 1,
6252 htlc_minimum_msat: 0,
6253 htlc_maximum_msat: 250_000_000,
6255 fee_proportional_millionths: 0,
6256 excess_data: Vec::new()
6258 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6259 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6260 short_channel_id: 13,
6263 cltv_expiry_delta: (13 << 4) | 1,
6264 htlc_minimum_msat: 0,
6265 htlc_maximum_msat: 250_000_000,
6267 fee_proportional_millionths: 0,
6268 excess_data: Vec::new()
6271 let config = UserConfig::default();
6272 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6273 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6274 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6275 // 100,000 sats is less than the available liquidity on each channel, set above.
6276 let route_params = RouteParameters::from_payment_params_and_value(
6277 payment_params, 100_000_000);
6278 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6279 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6280 assert_eq!(route.paths.len(), 2);
6281 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6282 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6285 #[cfg(not(feature = "no-std"))]
6286 pub(super) fn random_init_seed() -> u64 {
6287 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6288 use core::hash::{BuildHasher, Hasher};
6289 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6290 println!("Using seed of {}", seed);
6295 #[cfg(not(feature = "no-std"))]
6296 fn generate_routes() {
6297 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6299 let logger = ln_test_utils::TestLogger::new();
6300 let graph = match super::bench_utils::read_network_graph(&logger) {
6308 let params = ProbabilisticScoringFeeParameters::default();
6309 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6310 let features = super::Bolt11InvoiceFeatures::empty();
6312 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6316 #[cfg(not(feature = "no-std"))]
6317 fn generate_routes_mpp() {
6318 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6320 let logger = ln_test_utils::TestLogger::new();
6321 let graph = match super::bench_utils::read_network_graph(&logger) {
6329 let params = ProbabilisticScoringFeeParameters::default();
6330 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6331 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6333 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6337 #[cfg(not(feature = "no-std"))]
6338 fn generate_large_mpp_routes() {
6339 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6341 let logger = ln_test_utils::TestLogger::new();
6342 let graph = match super::bench_utils::read_network_graph(&logger) {
6350 let params = ProbabilisticScoringFeeParameters::default();
6351 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6352 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6354 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6358 fn honors_manual_penalties() {
6359 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6360 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6362 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6363 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6365 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6366 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6368 // First check set manual penalties are returned by the scorer.
6369 let usage = ChannelUsage {
6371 inflight_htlc_msat: 0,
6372 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6374 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6375 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6376 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6378 // Then check we can get a normal route
6379 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6380 let route_params = RouteParameters::from_payment_params_and_value(
6381 payment_params, 100);
6382 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6383 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6384 assert!(route.is_ok());
6386 // Then check that we can't get a route if we ban an intermediate node.
6387 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6388 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6389 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6390 assert!(route.is_err());
6392 // Finally make sure we can route again, when we remove the ban.
6393 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6394 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6395 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6396 assert!(route.is_ok());
6400 fn abide_by_route_hint_max_htlc() {
6401 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6402 // params in the final route.
6403 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6404 let netgraph = network_graph.read_only();
6405 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6406 let scorer = ln_test_utils::TestScorer::new();
6407 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6408 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6409 let config = UserConfig::default();
6411 let max_htlc_msat = 50_000;
6412 let route_hint_1 = RouteHint(vec![RouteHintHop {
6413 src_node_id: nodes[2],
6414 short_channel_id: 42,
6417 proportional_millionths: 0,
6419 cltv_expiry_delta: 10,
6420 htlc_minimum_msat: None,
6421 htlc_maximum_msat: Some(max_htlc_msat),
6423 let dest_node_id = ln_test_utils::pubkey(42);
6424 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6425 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6426 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6428 // Make sure we'll error if our route hints don't have enough liquidity according to their
6429 // htlc_maximum_msat.
6430 let route_params = RouteParameters::from_payment_params_and_value(
6431 payment_params, max_htlc_msat + 1);
6432 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6433 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(),
6436 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6437 } else { panic!(); }
6439 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6440 let mut route_hint_2 = route_hint_1.clone();
6441 route_hint_2.0[0].short_channel_id = 43;
6442 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6443 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6444 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6445 let route_params = RouteParameters::from_payment_params_and_value(
6446 payment_params, max_htlc_msat + 1);
6447 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6448 &scorer, &(), &random_seed_bytes).unwrap();
6449 assert_eq!(route.paths.len(), 2);
6450 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6451 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6455 fn direct_channel_to_hints_with_max_htlc() {
6456 // Check that if we have a first hop channel peer that's connected to multiple provided route
6457 // hints, that we properly split the payment between the route hints if needed.
6458 let logger = Arc::new(ln_test_utils::TestLogger::new());
6459 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6460 let scorer = ln_test_utils::TestScorer::new();
6461 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6462 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6463 let config = UserConfig::default();
6465 let our_node_id = ln_test_utils::pubkey(42);
6466 let intermed_node_id = ln_test_utils::pubkey(43);
6467 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6469 let amt_msat = 900_000;
6470 let max_htlc_msat = 500_000;
6471 let route_hint_1 = RouteHint(vec![RouteHintHop {
6472 src_node_id: intermed_node_id,
6473 short_channel_id: 44,
6476 proportional_millionths: 0,
6478 cltv_expiry_delta: 10,
6479 htlc_minimum_msat: None,
6480 htlc_maximum_msat: Some(max_htlc_msat),
6482 src_node_id: intermed_node_id,
6483 short_channel_id: 45,
6486 proportional_millionths: 0,
6488 cltv_expiry_delta: 10,
6489 htlc_minimum_msat: None,
6490 // Check that later route hint max htlcs don't override earlier ones
6491 htlc_maximum_msat: Some(max_htlc_msat - 50),
6493 let mut route_hint_2 = route_hint_1.clone();
6494 route_hint_2.0[0].short_channel_id = 46;
6495 route_hint_2.0[1].short_channel_id = 47;
6496 let dest_node_id = ln_test_utils::pubkey(44);
6497 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6498 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6499 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6501 let route_params = RouteParameters::from_payment_params_and_value(
6502 payment_params, amt_msat);
6503 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6504 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6505 &random_seed_bytes).unwrap();
6506 assert_eq!(route.paths.len(), 2);
6507 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6508 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6509 assert_eq!(route.get_total_amount(), amt_msat);
6511 // Re-run but with two first hop channels connected to the same route hint peers that must be
6513 let first_hops = vec![
6514 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6515 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6517 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6518 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6519 &random_seed_bytes).unwrap();
6520 assert_eq!(route.paths.len(), 2);
6521 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6522 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6523 assert_eq!(route.get_total_amount(), amt_msat);
6525 // Make sure this works for blinded route hints.
6526 let blinded_path = BlindedPath {
6527 introduction_node_id: intermed_node_id,
6528 blinding_point: ln_test_utils::pubkey(42),
6530 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6531 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6534 let blinded_payinfo = BlindedPayInfo {
6536 fee_proportional_millionths: 0,
6537 htlc_minimum_msat: 1,
6538 htlc_maximum_msat: max_htlc_msat,
6539 cltv_expiry_delta: 10,
6540 features: BlindedHopFeatures::empty(),
6542 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6543 let payment_params = PaymentParameters::blinded(vec![
6544 (blinded_payinfo.clone(), blinded_path.clone()),
6545 (blinded_payinfo.clone(), blinded_path.clone())])
6546 .with_bolt12_features(bolt12_features).unwrap();
6547 let route_params = RouteParameters::from_payment_params_and_value(
6548 payment_params, amt_msat);
6549 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6550 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6551 &random_seed_bytes).unwrap();
6552 assert_eq!(route.paths.len(), 2);
6553 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6554 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6555 assert_eq!(route.get_total_amount(), amt_msat);
6559 fn blinded_route_ser() {
6560 let blinded_path_1 = BlindedPath {
6561 introduction_node_id: ln_test_utils::pubkey(42),
6562 blinding_point: ln_test_utils::pubkey(43),
6564 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6565 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6568 let blinded_path_2 = BlindedPath {
6569 introduction_node_id: ln_test_utils::pubkey(46),
6570 blinding_point: ln_test_utils::pubkey(47),
6572 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6573 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6576 // (De)serialize a Route with 1 blinded path out of two total paths.
6577 let mut route = Route { paths: vec![Path {
6578 hops: vec![RouteHop {
6579 pubkey: ln_test_utils::pubkey(50),
6580 node_features: NodeFeatures::empty(),
6581 short_channel_id: 42,
6582 channel_features: ChannelFeatures::empty(),
6584 cltv_expiry_delta: 0,
6586 blinded_tail: Some(BlindedTail {
6587 hops: blinded_path_1.blinded_hops,
6588 blinding_point: blinded_path_1.blinding_point,
6589 excess_final_cltv_expiry_delta: 40,
6590 final_value_msat: 100,
6592 hops: vec![RouteHop {
6593 pubkey: ln_test_utils::pubkey(51),
6594 node_features: NodeFeatures::empty(),
6595 short_channel_id: 43,
6596 channel_features: ChannelFeatures::empty(),
6598 cltv_expiry_delta: 0,
6599 }], blinded_tail: None }],
6600 payment_params: None,
6602 let encoded_route = route.encode();
6603 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6604 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6605 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6607 // (De)serialize a Route with two paths, each containing a blinded tail.
6608 route.paths[1].blinded_tail = Some(BlindedTail {
6609 hops: blinded_path_2.blinded_hops,
6610 blinding_point: blinded_path_2.blinding_point,
6611 excess_final_cltv_expiry_delta: 41,
6612 final_value_msat: 101,
6614 let encoded_route = route.encode();
6615 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6616 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6617 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6621 fn blinded_path_inflight_processing() {
6622 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6623 // account for the blinded tail's final amount_msat.
6624 let mut inflight_htlcs = InFlightHtlcs::new();
6625 let blinded_path = BlindedPath {
6626 introduction_node_id: ln_test_utils::pubkey(43),
6627 blinding_point: ln_test_utils::pubkey(48),
6628 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6631 hops: vec![RouteHop {
6632 pubkey: ln_test_utils::pubkey(42),
6633 node_features: NodeFeatures::empty(),
6634 short_channel_id: 42,
6635 channel_features: ChannelFeatures::empty(),
6637 cltv_expiry_delta: 0,
6640 pubkey: blinded_path.introduction_node_id,
6641 node_features: NodeFeatures::empty(),
6642 short_channel_id: 43,
6643 channel_features: ChannelFeatures::empty(),
6645 cltv_expiry_delta: 0,
6647 blinded_tail: Some(BlindedTail {
6648 hops: blinded_path.blinded_hops,
6649 blinding_point: blinded_path.blinding_point,
6650 excess_final_cltv_expiry_delta: 0,
6651 final_value_msat: 200,
6654 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6655 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6656 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6660 fn blinded_path_cltv_shadow_offset() {
6661 // Make sure we add a shadow offset when sending to blinded paths.
6662 let blinded_path = BlindedPath {
6663 introduction_node_id: ln_test_utils::pubkey(43),
6664 blinding_point: ln_test_utils::pubkey(44),
6666 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6667 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6670 let mut route = Route { paths: vec![Path {
6671 hops: vec![RouteHop {
6672 pubkey: ln_test_utils::pubkey(42),
6673 node_features: NodeFeatures::empty(),
6674 short_channel_id: 42,
6675 channel_features: ChannelFeatures::empty(),
6677 cltv_expiry_delta: 0,
6680 pubkey: blinded_path.introduction_node_id,
6681 node_features: NodeFeatures::empty(),
6682 short_channel_id: 43,
6683 channel_features: ChannelFeatures::empty(),
6685 cltv_expiry_delta: 0,
6688 blinded_tail: Some(BlindedTail {
6689 hops: blinded_path.blinded_hops,
6690 blinding_point: blinded_path.blinding_point,
6691 excess_final_cltv_expiry_delta: 0,
6692 final_value_msat: 200,
6694 }], payment_params: None};
6696 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6697 let (_, network_graph, _, _, _) = build_line_graph();
6698 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6699 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6700 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6704 fn simple_blinded_route_hints() {
6705 do_simple_blinded_route_hints(1);
6706 do_simple_blinded_route_hints(2);
6707 do_simple_blinded_route_hints(3);
6710 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6711 // Check that we can generate a route to a blinded path with the expected hops.
6712 let (secp_ctx, network, _, _, logger) = build_graph();
6713 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6714 let network_graph = network.read_only();
6716 let scorer = ln_test_utils::TestScorer::new();
6717 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6718 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6720 let mut blinded_path = BlindedPath {
6721 introduction_node_id: nodes[2],
6722 blinding_point: ln_test_utils::pubkey(42),
6723 blinded_hops: Vec::with_capacity(num_blinded_hops),
6725 for i in 0..num_blinded_hops {
6726 blinded_path.blinded_hops.push(
6727 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6730 let blinded_payinfo = BlindedPayInfo {
6732 fee_proportional_millionths: 500,
6733 htlc_minimum_msat: 1000,
6734 htlc_maximum_msat: 100_000_000,
6735 cltv_expiry_delta: 15,
6736 features: BlindedHopFeatures::empty(),
6739 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6740 let route_params = RouteParameters::from_payment_params_and_value(
6741 payment_params, 1001);
6742 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6743 &scorer, &(), &random_seed_bytes).unwrap();
6744 assert_eq!(route.paths.len(), 1);
6745 assert_eq!(route.paths[0].hops.len(), 2);
6747 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6748 assert_eq!(tail.hops, blinded_path.blinded_hops);
6749 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6750 assert_eq!(tail.final_value_msat, 1001);
6752 let final_hop = route.paths[0].hops.last().unwrap();
6753 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6754 if tail.hops.len() > 1 {
6755 assert_eq!(final_hop.fee_msat,
6756 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6757 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6759 assert_eq!(final_hop.fee_msat, 0);
6760 assert_eq!(final_hop.cltv_expiry_delta, 0);
6765 fn blinded_path_routing_errors() {
6766 // Check that we can generate a route to a blinded path with the expected hops.
6767 let (secp_ctx, network, _, _, logger) = build_graph();
6768 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6769 let network_graph = network.read_only();
6771 let scorer = ln_test_utils::TestScorer::new();
6772 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6773 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6775 let mut invalid_blinded_path = BlindedPath {
6776 introduction_node_id: nodes[2],
6777 blinding_point: ln_test_utils::pubkey(42),
6779 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
6782 let blinded_payinfo = BlindedPayInfo {
6784 fee_proportional_millionths: 500,
6785 htlc_minimum_msat: 1000,
6786 htlc_maximum_msat: 100_000_000,
6787 cltv_expiry_delta: 15,
6788 features: BlindedHopFeatures::empty(),
6791 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
6792 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
6793 let payment_params = PaymentParameters::blinded(vec![
6794 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
6795 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
6796 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6797 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6798 &scorer, &(), &random_seed_bytes)
6800 Err(LightningError { err, .. }) => {
6801 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
6803 _ => panic!("Expected error")
6806 invalid_blinded_path.introduction_node_id = our_id;
6807 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
6808 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6809 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6810 &(), &random_seed_bytes)
6812 Err(LightningError { err, .. }) => {
6813 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
6815 _ => panic!("Expected error")
6818 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
6819 invalid_blinded_path.blinded_hops.clear();
6820 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
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), &scorer,
6823 &(), &random_seed_bytes)
6825 Err(LightningError { err, .. }) => {
6826 assert_eq!(err, "0-hop blinded path provided");
6828 _ => panic!("Expected error")
6833 fn matching_intro_node_paths_provided() {
6834 // Check that if multiple blinded paths with the same intro node are provided in payment
6835 // parameters, we'll return the correct paths in the resulting MPP route.
6836 let (secp_ctx, network, _, _, logger) = build_graph();
6837 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6838 let network_graph = network.read_only();
6840 let scorer = ln_test_utils::TestScorer::new();
6841 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6842 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6843 let config = UserConfig::default();
6845 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6846 let blinded_path_1 = BlindedPath {
6847 introduction_node_id: nodes[2],
6848 blinding_point: ln_test_utils::pubkey(42),
6850 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6851 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6854 let blinded_payinfo_1 = BlindedPayInfo {
6856 fee_proportional_millionths: 0,
6857 htlc_minimum_msat: 0,
6858 htlc_maximum_msat: 30_000,
6859 cltv_expiry_delta: 0,
6860 features: BlindedHopFeatures::empty(),
6863 let mut blinded_path_2 = blinded_path_1.clone();
6864 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
6865 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
6866 blinded_payinfo_2.htlc_maximum_msat = 70_000;
6868 let blinded_hints = vec![
6869 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
6870 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
6872 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
6873 .with_bolt12_features(bolt12_features.clone()).unwrap();
6875 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
6876 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6877 &scorer, &(), &random_seed_bytes).unwrap();
6878 assert_eq!(route.paths.len(), 2);
6879 let mut total_amount_paid_msat = 0;
6880 for path in route.paths.into_iter() {
6881 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6882 if let Some(bt) = &path.blinded_tail {
6883 assert_eq!(bt.blinding_point,
6884 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
6885 .map(|(_, bp)| bp.blinding_point).unwrap());
6886 } else { panic!(); }
6887 total_amount_paid_msat += path.final_value_msat();
6889 assert_eq!(total_amount_paid_msat, 100_000);
6893 fn direct_to_intro_node() {
6894 // This previously caused a debug panic in the router when asserting
6895 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
6896 // direct channels we failed to account for the fee charged for use of the blinded path.
6899 // node0 -1(1)2 - node1
6900 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
6901 // doesn't account for the blinded path fee.
6903 let secp_ctx = Secp256k1::new();
6904 let logger = Arc::new(ln_test_utils::TestLogger::new());
6905 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6906 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
6907 let scorer = ln_test_utils::TestScorer::new();
6908 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6909 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6911 let amt_msat = 10_000_000;
6912 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
6913 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
6914 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
6915 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
6916 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6917 short_channel_id: 1,
6920 cltv_expiry_delta: 42,
6921 htlc_minimum_msat: 1_000,
6922 htlc_maximum_msat: 10_000_000,
6924 fee_proportional_millionths: 0,
6925 excess_data: Vec::new()
6927 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6928 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6929 short_channel_id: 1,
6932 cltv_expiry_delta: 42,
6933 htlc_minimum_msat: 1_000,
6934 htlc_maximum_msat: 10_000_000,
6936 fee_proportional_millionths: 0,
6937 excess_data: Vec::new()
6939 let first_hops = vec![
6940 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6942 let blinded_path = BlindedPath {
6943 introduction_node_id: nodes[1],
6944 blinding_point: ln_test_utils::pubkey(42),
6946 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6947 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6950 let blinded_payinfo = BlindedPayInfo {
6951 fee_base_msat: 1000,
6952 fee_proportional_millionths: 0,
6953 htlc_minimum_msat: 1000,
6954 htlc_maximum_msat: MAX_VALUE_MSAT,
6955 cltv_expiry_delta: 0,
6956 features: BlindedHopFeatures::empty(),
6958 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
6960 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
6962 let netgraph = network_graph.read_only();
6963 let route_params = RouteParameters::from_payment_params_and_value(
6964 payment_params.clone(), amt_msat);
6965 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
6966 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6967 &random_seed_bytes) {
6968 assert_eq!(err, "Failed to find a path to the given destination");
6969 } else { panic!("Expected error") }
6971 // Sending an exact amount accounting for the blinded path fee works.
6972 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
6973 let route_params = RouteParameters::from_payment_params_and_value(
6974 payment_params, amt_minus_blinded_path_fee);
6975 let route = get_route(&nodes[0], &route_params, &netgraph,
6976 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
6977 &random_seed_bytes).unwrap();
6978 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
6979 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
6983 fn direct_to_matching_intro_nodes() {
6984 // This previously caused us to enter `unreachable` code in the following situation:
6985 // 1. We add a route candidate for intro_node contributing a high amount
6986 // 2. We add a first_hop<>intro_node route candidate for the same high amount
6987 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
6988 // amount, and update our route candidate for intro_node for the lower amount
6989 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
6990 // lower contribution amount, but fail (this was previously caused by failure to account for
6991 // blinded path fees when adding first_hop<>intro_node candidates)
6992 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
6993 // candidate still thinks its path is contributing the original higher amount. This caused us
6994 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
6996 let secp_ctx = Secp256k1::new();
6997 let logger = Arc::new(ln_test_utils::TestLogger::new());
6998 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6999 let scorer = ln_test_utils::TestScorer::new();
7000 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7001 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7002 let config = UserConfig::default();
7004 // Values are taken from the fuzz input that uncovered this panic.
7005 let amt_msat = 21_7020_5185_1403_2640;
7006 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7007 let first_hops = vec![
7008 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7009 18446744073709551615)];
7011 let blinded_path = BlindedPath {
7012 introduction_node_id: nodes[1],
7013 blinding_point: ln_test_utils::pubkey(42),
7015 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7016 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7019 let blinded_payinfo = BlindedPayInfo {
7020 fee_base_msat: 5046_2720,
7021 fee_proportional_millionths: 0,
7022 htlc_minimum_msat: 4503_5996_2737_0496,
7023 htlc_maximum_msat: 45_0359_9627_3704_9600,
7024 cltv_expiry_delta: 0,
7025 features: BlindedHopFeatures::empty(),
7027 let mut blinded_hints = vec![
7028 (blinded_payinfo.clone(), blinded_path.clone()),
7029 (blinded_payinfo.clone(), blinded_path.clone()),
7031 blinded_hints[1].0.fee_base_msat = 419_4304;
7032 blinded_hints[1].0.fee_proportional_millionths = 257;
7033 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7034 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7035 blinded_hints[1].0.cltv_expiry_delta = 0;
7037 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7038 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7039 .with_bolt12_features(bolt12_features.clone()).unwrap();
7041 let netgraph = network_graph.read_only();
7042 let route_params = RouteParameters::from_payment_params_and_value(
7043 payment_params, amt_msat);
7044 let route = get_route(&nodes[0], &route_params, &netgraph,
7045 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer, &(),
7046 &random_seed_bytes).unwrap();
7047 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7048 assert_eq!(route.get_total_amount(), amt_msat);
7052 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7053 pub(crate) mod bench_utils {
7057 use bitcoin::hashes::Hash;
7058 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7060 use crate::chain::transaction::OutPoint;
7061 use crate::routing::scoring::ScoreUpdate;
7062 use crate::sign::{EntropySource, KeysManager};
7063 use crate::ln::ChannelId;
7064 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7065 use crate::ln::features::Bolt11InvoiceFeatures;
7066 use crate::routing::gossip::NetworkGraph;
7067 use crate::util::config::UserConfig;
7068 use crate::util::ser::ReadableArgs;
7069 use crate::util::test_utils::TestLogger;
7071 /// Tries to open a network graph file, or panics with a URL to fetch it.
7072 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7073 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7074 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7075 .or_else(|_| { // Fall back to guessing based on the binary location
7076 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7077 let mut path = std::env::current_exe().unwrap();
7078 path.pop(); // lightning-...
7080 path.pop(); // debug
7081 path.pop(); // target
7082 path.push("lightning");
7083 path.push("net_graph-2023-01-18.bin");
7086 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7087 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7088 let mut path = std::env::current_exe().unwrap();
7089 path.pop(); // bench...
7091 path.pop(); // debug
7092 path.pop(); // target
7093 path.pop(); // bench
7094 path.push("lightning");
7095 path.push("net_graph-2023-01-18.bin");
7098 .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");
7099 #[cfg(require_route_graph_test)]
7100 return Ok(res.unwrap());
7101 #[cfg(not(require_route_graph_test))]
7105 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7106 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7109 pub(crate) fn payer_pubkey() -> PublicKey {
7110 let secp_ctx = Secp256k1::new();
7111 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7115 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7117 channel_id: ChannelId::new_zero(),
7118 counterparty: ChannelCounterparty {
7119 features: channelmanager::provided_init_features(&UserConfig::default()),
7121 unspendable_punishment_reserve: 0,
7122 forwarding_info: None,
7123 outbound_htlc_minimum_msat: None,
7124 outbound_htlc_maximum_msat: None,
7126 funding_txo: Some(OutPoint {
7127 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7130 short_channel_id: Some(1),
7131 inbound_scid_alias: None,
7132 outbound_scid_alias: None,
7133 channel_value_satoshis: 10_000_000_000,
7135 outbound_capacity_msat: 10_000_000_000,
7136 next_outbound_htlc_minimum_msat: 0,
7137 next_outbound_htlc_limit_msat: 10_000_000_000,
7138 inbound_capacity_msat: 0,
7139 unspendable_punishment_reserve: None,
7140 confirmations_required: None,
7141 confirmations: None,
7142 force_close_spend_delay: None,
7144 is_channel_ready: true,
7147 inbound_htlc_minimum_msat: None,
7148 inbound_htlc_maximum_msat: None,
7150 feerate_sat_per_1000_weight: None,
7151 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7155 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7156 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7157 starting_amount: u64, route_count: usize,
7158 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7159 let payer = payer_pubkey();
7160 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7161 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7163 let nodes = graph.read_only().nodes().clone();
7164 let mut route_endpoints = Vec::new();
7165 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7166 // with some routes we picked being un-routable.
7167 for _ in 0..route_count * 3 / 2 {
7169 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7170 let src = PublicKey::from_slice(nodes.unordered_keys()
7171 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7172 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7173 let dst = PublicKey::from_slice(nodes.unordered_keys()
7174 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7175 let params = PaymentParameters::from_node_id(dst, 42)
7176 .with_bolt11_features(features.clone()).unwrap();
7177 let first_hop = first_hop(src);
7178 let amt_msat = starting_amount + seed % 1_000_000;
7179 let route_params = RouteParameters::from_payment_params_and_value(
7180 params.clone(), amt_msat);
7182 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7183 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7185 // ...and seed the scorer with success and failure data...
7186 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7187 let mut score_amt = seed % 1_000_000_000;
7189 // Generate fail/success paths for a wider range of potential amounts with
7190 // MPP enabled to give us a chance to apply penalties for more potential
7192 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7193 let params = PaymentParameters::from_node_id(dst, 42)
7194 .with_bolt11_features(mpp_features).unwrap();
7195 let route_params = RouteParameters::from_payment_params_and_value(
7196 params.clone(), score_amt);
7197 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7198 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7199 &random_seed_bytes);
7200 if let Ok(route) = route_res {
7201 for path in route.paths {
7202 if seed & 0x80 == 0 {
7203 scorer.payment_path_successful(&path);
7205 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7206 scorer.payment_path_failed(&path, short_channel_id);
7208 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7212 // If we couldn't find a path with a higer amount, reduce and try again.
7216 route_endpoints.push((first_hop, params, amt_msat));
7222 // Because we've changed channel scores, it's possible we'll take different routes to the
7223 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7224 // requires a too-high CLTV delta.
7225 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7226 let route_params = RouteParameters::from_payment_params_and_value(
7227 params.clone(), *amt_msat);
7228 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7229 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7231 route_endpoints.truncate(route_count);
7232 assert_eq!(route_endpoints.len(), route_count);
7240 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7241 use crate::sign::{EntropySource, KeysManager};
7242 use crate::ln::channelmanager;
7243 use crate::ln::features::Bolt11InvoiceFeatures;
7244 use crate::routing::gossip::NetworkGraph;
7245 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7246 use crate::util::config::UserConfig;
7247 use crate::util::logger::{Logger, Record};
7248 use crate::util::test_utils::TestLogger;
7250 use criterion::Criterion;
7252 struct DummyLogger {}
7253 impl Logger for DummyLogger {
7254 fn log(&self, _record: &Record) {}
7257 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7258 let logger = TestLogger::new();
7259 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7260 let scorer = FixedPenaltyScorer::with_penalty(0);
7261 generate_routes(bench, &network_graph, scorer, &(), Bolt11InvoiceFeatures::empty(), 0,
7262 "generate_routes_with_zero_penalty_scorer");
7265 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7266 let logger = TestLogger::new();
7267 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7268 let scorer = FixedPenaltyScorer::with_penalty(0);
7269 generate_routes(bench, &network_graph, scorer, &(),
7270 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7271 "generate_mpp_routes_with_zero_penalty_scorer");
7274 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7275 let logger = TestLogger::new();
7276 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7277 let params = ProbabilisticScoringFeeParameters::default();
7278 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7279 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7280 "generate_routes_with_probabilistic_scorer");
7283 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7284 let logger = TestLogger::new();
7285 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7286 let params = ProbabilisticScoringFeeParameters::default();
7287 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7288 generate_routes(bench, &network_graph, scorer, ¶ms,
7289 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7290 "generate_mpp_routes_with_probabilistic_scorer");
7293 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7294 let logger = TestLogger::new();
7295 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7296 let params = ProbabilisticScoringFeeParameters::default();
7297 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7298 generate_routes(bench, &network_graph, scorer, ¶ms,
7299 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7300 "generate_large_mpp_routes_with_probabilistic_scorer");
7303 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7304 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7305 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7306 bench_name: &'static str,
7308 let payer = bench_utils::payer_pubkey();
7309 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7310 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7312 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7313 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7315 // ...then benchmark finding paths between the nodes we learned.
7317 bench.bench_function(bench_name, |b| b.iter(|| {
7318 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
7319 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
7320 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7321 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());