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, Score};
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;
33 use core::ops::{Deref, DerefMut};
35 /// A [`Router`] implemented using [`find_route`].
36 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: Score<ScoreParams = SP>> where
38 S::Target: for <'a> LockableScore<'a, Score = Sc>,
42 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: Score<ScoreParams = SP>> DefaultRouter<G, L, S, SP, Sc> where
49 S::Target: for <'a> LockableScore<'a, Score = 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: Score<ScoreParams = SP>> Router for DefaultRouter<G, L, S, SP, Sc> where
60 S::Target: for <'a> LockableScore<'a, Score = 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.lock().deref_mut(), &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 /// [`Score`] implementation that factors in in-flight HTLC liquidity.
111 /// Useful for custom [`Router`] implementations to wrap their [`Score`] on-the-fly when calling
114 /// [`Score`]: crate::routing::scoring::Score
115 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Score<ScoreParams = SP>, SP: Sized> {
117 // Maps a channel's short channel id and its direction to the liquidity used up.
118 inflight_htlcs: &'a InFlightHtlcs,
121 impl<'a, S: Score<ScoreParams = SP>, SP: Sized> ScorerAccountingForInFlightHtlcs<'a, S, SP> {
122 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
123 pub fn new(scorer: &'a mut S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
124 ScorerAccountingForInFlightHtlcs {
132 impl<'a, S: Score<ScoreParams = SP>, SP: Sized> Writeable for ScorerAccountingForInFlightHtlcs<'a, S, SP> {
133 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
136 impl<'a, S: Score<ScoreParams = SP>, SP: Sized> Score for ScorerAccountingForInFlightHtlcs<'a, S, SP> {
137 type ScoreParams = S::ScoreParams;
138 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
139 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
140 source, target, short_channel_id
142 let usage = ChannelUsage {
143 inflight_htlc_msat: usage.inflight_htlc_msat + used_liquidity,
147 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
149 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
153 fn payment_path_failed(&mut self, path: &Path, short_channel_id: u64) {
154 self.scorer.payment_path_failed(path, short_channel_id)
157 fn payment_path_successful(&mut self, path: &Path) {
158 self.scorer.payment_path_successful(path)
161 fn probe_failed(&mut self, path: &Path, short_channel_id: u64) {
162 self.scorer.probe_failed(path, short_channel_id)
165 fn probe_successful(&mut self, path: &Path) {
166 self.scorer.probe_successful(path)
170 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
171 /// in-use channel liquidity.
173 pub struct InFlightHtlcs(
174 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
175 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
176 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
178 HashMap<(u64, bool), u64>
182 /// Constructs an empty `InFlightHtlcs`.
183 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
185 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
186 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
187 if path.hops.is_empty() { return };
189 let mut cumulative_msat = 0;
190 if let Some(tail) = &path.blinded_tail {
191 cumulative_msat += tail.final_value_msat;
194 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
195 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
196 // the router excludes the payer node. In the following lines, the payer's information is
197 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
198 // in our sliding window of two.
199 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
200 .map(|hop| hop.pubkey)
201 .chain(core::iter::once(payer_node_id));
203 // Taking the reversed vector from above, we zip it with just the reversed hops list to
204 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
205 // the total amount sent.
206 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
207 cumulative_msat += next_hop.fee_msat;
209 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
210 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
211 .or_insert(cumulative_msat);
215 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
217 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
219 .entry((channel_scid, source < target))
220 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
221 .or_insert(used_msat);
224 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
226 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
227 self.0.get(&(channel_scid, source < target)).map(|v| *v)
231 impl Writeable for InFlightHtlcs {
232 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
235 impl Readable for InFlightHtlcs {
236 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
237 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
238 Ok(Self(infight_map))
242 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
243 /// that leads to it.
244 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
245 pub struct RouteHop {
246 /// The node_id of the node at this hop.
247 pub pubkey: PublicKey,
248 /// The node_announcement features of the node at this hop. For the last hop, these may be
249 /// amended to match the features present in the invoice this node generated.
250 pub node_features: NodeFeatures,
251 /// The channel that should be used from the previous hop to reach this node.
252 pub short_channel_id: u64,
253 /// The channel_announcement features of the channel that should be used from the previous hop
254 /// to reach this node.
255 pub channel_features: ChannelFeatures,
256 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
257 /// If this is the last hop in [`Path::hops`]:
258 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
259 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
261 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
263 /// The CLTV delta added for this hop.
264 /// If this is the last hop in [`Path::hops`]:
265 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
266 /// * otherwise, this is the CLTV delta expected at the destination
268 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
269 pub cltv_expiry_delta: u32,
272 impl_writeable_tlv_based!(RouteHop, {
273 (0, pubkey, required),
274 (2, node_features, required),
275 (4, short_channel_id, required),
276 (6, channel_features, required),
277 (8, fee_msat, required),
278 (10, cltv_expiry_delta, required),
281 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
282 /// their [`Bolt12Invoice`].
284 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
285 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
286 pub struct BlindedTail {
287 /// The hops of the [`BlindedPath`] provided by the recipient.
289 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
290 pub hops: Vec<BlindedHop>,
291 /// The blinding point of the [`BlindedPath`] provided by the recipient.
293 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
294 pub blinding_point: PublicKey,
295 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
296 /// inferring the destination. May be 0.
297 pub excess_final_cltv_expiry_delta: u32,
298 /// The total amount paid on this [`Path`], excluding the fees.
299 pub final_value_msat: u64,
302 impl_writeable_tlv_based!(BlindedTail, {
303 (0, hops, required_vec),
304 (2, blinding_point, required),
305 (4, excess_final_cltv_expiry_delta, required),
306 (6, final_value_msat, required),
309 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
310 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
311 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
313 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
314 pub hops: Vec<RouteHop>,
315 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
316 pub blinded_tail: Option<BlindedTail>,
320 /// Gets the fees for a given path, excluding any excess paid to the recipient.
321 pub fn fee_msat(&self) -> u64 {
322 match &self.blinded_tail {
323 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
325 // Do not count last hop of each path since that's the full value of the payment
326 self.hops.split_last().map_or(0,
327 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
332 /// Gets the total amount paid on this [`Path`], excluding the fees.
333 pub fn final_value_msat(&self) -> u64 {
334 match &self.blinded_tail {
335 Some(blinded_tail) => blinded_tail.final_value_msat,
336 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
340 /// Gets the final hop's CLTV expiry delta.
341 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
342 match &self.blinded_tail {
344 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
349 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
350 /// it can take multiple paths. Each path is composed of one or more hops through the network.
351 #[derive(Clone, Hash, PartialEq, Eq)]
353 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
354 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
356 pub paths: Vec<Path>,
357 /// The `payment_params` parameter passed via [`RouteParameters`] to [`find_route`].
359 /// This is used by `ChannelManager` to track information which may be required for retries.
360 pub payment_params: Option<PaymentParameters>,
364 /// Returns the total amount of fees paid on this [`Route`].
366 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
367 /// the amount passed to [`find_route`]'s `route_params.final_value_msat`.
368 pub fn get_total_fees(&self) -> u64 {
369 self.paths.iter().map(|path| path.fee_msat()).sum()
372 /// Returns the total amount paid on this [`Route`], excluding the fees. Might be more than
373 /// requested if we had to reach htlc_minimum_msat.
374 pub fn get_total_amount(&self) -> u64 {
375 self.paths.iter().map(|path| path.final_value_msat()).sum()
379 const SERIALIZATION_VERSION: u8 = 1;
380 const MIN_SERIALIZATION_VERSION: u8 = 1;
382 impl Writeable for Route {
383 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
384 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
385 (self.paths.len() as u64).write(writer)?;
386 let mut blinded_tails = Vec::new();
387 for path in self.paths.iter() {
388 (path.hops.len() as u8).write(writer)?;
389 for (idx, hop) in path.hops.iter().enumerate() {
391 if let Some(blinded_tail) = &path.blinded_tail {
392 if blinded_tails.is_empty() {
393 blinded_tails = Vec::with_capacity(path.hops.len());
395 blinded_tails.push(None);
398 blinded_tails.push(Some(blinded_tail));
399 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
402 write_tlv_fields!(writer, {
403 (1, self.payment_params, option),
404 (2, blinded_tails, optional_vec),
410 impl Readable for Route {
411 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
412 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
413 let path_count: u64 = Readable::read(reader)?;
414 if path_count == 0 { return Err(DecodeError::InvalidValue); }
415 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
416 let mut min_final_cltv_expiry_delta = u32::max_value();
417 for _ in 0..path_count {
418 let hop_count: u8 = Readable::read(reader)?;
419 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
420 for _ in 0..hop_count {
421 hops.push(Readable::read(reader)?);
423 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
424 min_final_cltv_expiry_delta =
425 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
426 paths.push(Path { hops, blinded_tail: None });
428 _init_and_read_tlv_fields!(reader, {
429 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
430 (2, blinded_tails, optional_vec),
432 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
433 if blinded_tails.len() != 0 {
434 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
435 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
436 path.blinded_tail = blinded_tail_opt;
439 Ok(Route { paths, payment_params })
443 /// Parameters needed to find a [`Route`].
445 /// Passed to [`find_route`] and [`build_route_from_hops`].
446 #[derive(Clone, Debug, PartialEq, Eq)]
447 pub struct RouteParameters {
448 /// The parameters of the failed payment path.
449 pub payment_params: PaymentParameters,
451 /// The amount in msats sent on the failed payment path.
452 pub final_value_msat: u64,
455 impl Writeable for RouteParameters {
456 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
457 write_tlv_fields!(writer, {
458 (0, self.payment_params, required),
459 (2, self.final_value_msat, required),
460 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
461 // `RouteParameters` directly. For compatibility, we write it here.
462 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
468 impl Readable for RouteParameters {
469 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
470 _init_and_read_tlv_fields!(reader, {
471 (0, payment_params, (required: ReadableArgs, 0)),
472 (2, final_value_msat, required),
473 (4, final_cltv_delta, option),
475 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
476 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
477 if final_cltv_expiry_delta == &0 {
478 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
483 final_value_msat: final_value_msat.0.unwrap(),
488 /// Maximum total CTLV difference we allow for a full payment path.
489 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
491 /// Maximum number of paths we allow an (MPP) payment to have.
492 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
493 // limits, but for now more than 10 paths likely carries too much one-path failure.
494 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
496 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
498 // The median hop CLTV expiry delta currently seen in the network.
499 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
501 // During routing, we only consider paths shorter than our maximum length estimate.
502 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
503 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
504 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
506 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
507 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
508 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
509 // (payment_secret and total_msat) = 93 bytes for the final hop.
510 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
511 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
512 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
514 /// Information used to route a payment.
515 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
516 pub struct PaymentParameters {
517 /// Information about the payee, such as their features and route hints for their channels.
520 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
521 pub expiry_time: Option<u64>,
523 /// The maximum total CLTV delta we accept for the route.
524 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
525 pub max_total_cltv_expiry_delta: u32,
527 /// The maximum number of paths that may be used by (MPP) payments.
528 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
529 pub max_path_count: u8,
531 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
532 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
533 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
534 /// increasing failure probability for those paths.
536 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
537 /// restriction have been found. While paths which meet this criteria will be searched for, it
538 /// is ultimately up to the scorer to select them over other paths.
540 /// A value of 0 will allow payments up to and including a channel's total announced usable
541 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
544 pub max_channel_saturation_power_of_half: u8,
546 /// A list of SCIDs which this payment was previously attempted over and which caused the
547 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
549 pub previously_failed_channels: Vec<u64>,
552 impl Writeable for PaymentParameters {
553 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
554 let mut clear_hints = &vec![];
555 let mut blinded_hints = &vec![];
557 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
558 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
560 write_tlv_fields!(writer, {
561 (0, self.payee.node_id(), option),
562 (1, self.max_total_cltv_expiry_delta, required),
563 (2, self.payee.features(), option),
564 (3, self.max_path_count, required),
565 (4, *clear_hints, required_vec),
566 (5, self.max_channel_saturation_power_of_half, required),
567 (6, self.expiry_time, option),
568 (7, self.previously_failed_channels, required_vec),
569 (8, *blinded_hints, optional_vec),
570 (9, self.payee.final_cltv_expiry_delta(), option),
576 impl ReadableArgs<u32> for PaymentParameters {
577 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
578 _init_and_read_tlv_fields!(reader, {
579 (0, payee_pubkey, option),
580 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
581 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
582 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
583 (4, clear_route_hints, required_vec),
584 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
585 (6, expiry_time, option),
586 (7, previously_failed_channels, optional_vec),
587 (8, blinded_route_hints, optional_vec),
588 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
590 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
591 let payee = if blinded_route_hints.len() != 0 {
592 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
594 route_hints: blinded_route_hints,
595 features: features.and_then(|f: Features| f.bolt12()),
599 route_hints: clear_route_hints,
600 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
601 features: features.and_then(|f| f.bolt11()),
602 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
606 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
607 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
609 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
611 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
617 impl PaymentParameters {
618 /// Creates a payee with the node id of the given `pubkey`.
620 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
622 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
624 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
626 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
627 max_path_count: DEFAULT_MAX_PATH_COUNT,
628 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
629 previously_failed_channels: Vec::new(),
633 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
635 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
638 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
639 /// whether your router will be allowed to find a multi-part route for this payment. If you
640 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
641 /// [`RecipientOnionFields::secret_only`].
643 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
644 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
645 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
646 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
647 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
650 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
651 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
652 /// [`PaymentParameters::expiry_time`].
653 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
654 Self::blinded(invoice.payment_paths().to_vec())
655 .with_bolt12_features(invoice.features().clone()).unwrap()
656 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
659 fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
661 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
663 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
664 max_path_count: DEFAULT_MAX_PATH_COUNT,
665 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
666 previously_failed_channels: Vec::new(),
670 /// Includes the payee's features. Errors if the parameters were not initialized with
671 /// [`PaymentParameters::from_bolt12_invoice`].
673 /// This is not exported to bindings users since bindings don't support move semantics
674 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
676 Payee::Clear { .. } => Err(()),
677 Payee::Blinded { route_hints, .. } =>
678 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
682 /// Includes the payee's features. Errors if the parameters were initialized with
683 /// [`PaymentParameters::from_bolt12_invoice`].
685 /// This is not exported to bindings users since bindings don't support move semantics
686 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
688 Payee::Blinded { .. } => Err(()),
689 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
691 payee: Payee::Clear {
692 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
698 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
699 /// [`PaymentParameters::from_bolt12_invoice`].
701 /// This is not exported to bindings users since bindings don't support move semantics
702 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
704 Payee::Blinded { .. } => Err(()),
705 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
707 payee: Payee::Clear {
708 route_hints, node_id, features, final_cltv_expiry_delta,
714 /// Includes a payment expiration in seconds relative to the UNIX epoch.
716 /// This is not exported to bindings users since bindings don't support move semantics
717 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
718 Self { expiry_time: Some(expiry_time), ..self }
721 /// Includes a limit for the total CLTV expiry delta which is considered during routing
723 /// This is not exported to bindings users since bindings don't support move semantics
724 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
725 Self { max_total_cltv_expiry_delta, ..self }
728 /// Includes a limit for the maximum number of payment paths that may be used.
730 /// This is not exported to bindings users since bindings don't support move semantics
731 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
732 Self { max_path_count, ..self }
735 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
736 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
738 /// This is not exported to bindings users since bindings don't support move semantics
739 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
740 Self { max_channel_saturation_power_of_half, ..self }
744 /// The recipient of a payment, differing based on whether they've hidden their identity with route
746 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
748 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
749 /// will be included in the final [`Route`].
751 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
753 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
754 /// Features supported by the payee.
756 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
758 features: Option<Bolt12InvoiceFeatures>,
760 /// The recipient included these route hints in their BOLT11 invoice.
762 /// The node id of the payee.
764 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
765 route_hints: Vec<RouteHint>,
766 /// Features supported by the payee.
768 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
769 /// does not contain any features.
771 /// [`for_keysend`]: PaymentParameters::for_keysend
772 features: Option<Bolt11InvoiceFeatures>,
773 /// The minimum CLTV delta at the end of the route. This value must not be zero.
774 final_cltv_expiry_delta: u32,
779 fn node_id(&self) -> Option<PublicKey> {
781 Self::Clear { node_id, .. } => Some(*node_id),
785 fn node_features(&self) -> Option<NodeFeatures> {
787 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
788 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
791 fn supports_basic_mpp(&self) -> bool {
793 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
794 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
797 fn features(&self) -> Option<FeaturesRef> {
799 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
800 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
803 fn final_cltv_expiry_delta(&self) -> Option<u32> {
805 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
809 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
811 Self::Blinded { route_hints, .. } => &route_hints[..],
812 Self::Clear { .. } => &[]
816 fn unblinded_route_hints(&self) -> &[RouteHint] {
818 Self::Blinded { .. } => &[],
819 Self::Clear { route_hints, .. } => &route_hints[..]
824 enum FeaturesRef<'a> {
825 Bolt11(&'a Bolt11InvoiceFeatures),
826 Bolt12(&'a Bolt12InvoiceFeatures),
829 Bolt11(Bolt11InvoiceFeatures),
830 Bolt12(Bolt12InvoiceFeatures),
834 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
836 Self::Bolt12(f) => Some(f),
840 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
842 Self::Bolt11(f) => Some(f),
848 impl<'a> Writeable for FeaturesRef<'a> {
849 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
851 Self::Bolt11(f) => Ok(f.write(w)?),
852 Self::Bolt12(f) => Ok(f.write(w)?),
857 impl ReadableArgs<bool> for Features {
858 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
859 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
860 Ok(Self::Bolt12(Readable::read(reader)?))
864 /// A list of hops along a payment path terminating with a channel to the recipient.
865 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
866 pub struct RouteHint(pub Vec<RouteHintHop>);
868 impl Writeable for RouteHint {
869 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
870 (self.0.len() as u64).write(writer)?;
871 for hop in self.0.iter() {
878 impl Readable for RouteHint {
879 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
880 let hop_count: u64 = Readable::read(reader)?;
881 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
882 for _ in 0..hop_count {
883 hops.push(Readable::read(reader)?);
889 /// A channel descriptor for a hop along a payment path.
890 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
891 pub struct RouteHintHop {
892 /// The node_id of the non-target end of the route
893 pub src_node_id: PublicKey,
894 /// The short_channel_id of this channel
895 pub short_channel_id: u64,
896 /// The fees which must be paid to use this channel
897 pub fees: RoutingFees,
898 /// The difference in CLTV values between this node and the next node.
899 pub cltv_expiry_delta: u16,
900 /// The minimum value, in msat, which must be relayed to the next hop.
901 pub htlc_minimum_msat: Option<u64>,
902 /// The maximum value in msat available for routing with a single HTLC.
903 pub htlc_maximum_msat: Option<u64>,
906 impl_writeable_tlv_based!(RouteHintHop, {
907 (0, src_node_id, required),
908 (1, htlc_minimum_msat, option),
909 (2, short_channel_id, required),
910 (3, htlc_maximum_msat, option),
912 (6, cltv_expiry_delta, required),
915 #[derive(Eq, PartialEq)]
916 struct RouteGraphNode {
918 lowest_fee_to_node: u64,
919 total_cltv_delta: u32,
920 // The maximum value a yet-to-be-constructed payment path might flow through this node.
921 // This value is upper-bounded by us by:
922 // - how much is needed for a path being constructed
923 // - how much value can channels following this node (up to the destination) can contribute,
924 // considering their capacity and fees
925 value_contribution_msat: u64,
926 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
927 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
928 path_htlc_minimum_msat: u64,
929 /// All penalties incurred from this hop on the way to the destination, as calculated using
931 path_penalty_msat: u64,
932 /// The number of hops walked up to this node.
933 path_length_to_node: u8,
936 impl cmp::Ord for RouteGraphNode {
937 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
938 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
939 .saturating_add(other.path_penalty_msat);
940 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
941 .saturating_add(self.path_penalty_msat);
942 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
946 impl cmp::PartialOrd for RouteGraphNode {
947 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
948 Some(self.cmp(other))
952 /// A wrapper around the various hop representations.
954 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
955 #[derive(Clone, Debug)]
956 enum CandidateRouteHop<'a> {
957 /// A hop from the payer, where the outbound liquidity is known.
959 details: &'a ChannelDetails,
961 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
963 info: DirectedChannelInfo<'a>,
964 short_channel_id: u64,
966 /// A hop to the payee found in the BOLT 11 payment invoice, though not necessarily a direct
969 hint: &'a RouteHintHop,
971 /// The payee's identity is concealed behind blinded paths provided in a BOLT 12 invoice.
973 hint: &'a (BlindedPayInfo, BlindedPath),
976 /// Similar to [`Self::Blinded`], but the path here has 1 blinded hop. `BlindedPayInfo` provided
977 /// for 1-hop blinded paths is ignored because it is meant to apply to the hops *between* the
978 /// introduction node and the destination. Useful for tracking that we need to include a blinded
979 /// path at the end of our [`Route`].
981 hint: &'a (BlindedPayInfo, BlindedPath),
986 impl<'a> CandidateRouteHop<'a> {
987 fn short_channel_id(&self) -> Option<u64> {
989 CandidateRouteHop::FirstHop { details } => Some(details.get_outbound_payment_scid().unwrap()),
990 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
991 CandidateRouteHop::PrivateHop { hint } => Some(hint.short_channel_id),
992 CandidateRouteHop::Blinded { .. } => None,
993 CandidateRouteHop::OneHopBlinded { .. } => None,
997 // NOTE: This may alloc memory so avoid calling it in a hot code path.
998 fn features(&self) -> ChannelFeatures {
1000 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
1001 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1002 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1003 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1004 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1008 fn cltv_expiry_delta(&self) -> u32 {
1010 CandidateRouteHop::FirstHop { .. } => 0,
1011 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1012 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
1013 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1014 CandidateRouteHop::OneHopBlinded { .. } => 0,
1018 fn htlc_minimum_msat(&self) -> u64 {
1020 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat,
1021 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1022 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
1023 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1024 CandidateRouteHop::OneHopBlinded { .. } => 0,
1028 fn fees(&self) -> RoutingFees {
1030 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1031 base_msat: 0, proportional_millionths: 0,
1033 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1034 CandidateRouteHop::PrivateHop { hint } => hint.fees,
1035 CandidateRouteHop::Blinded { hint, .. } => {
1037 base_msat: hint.0.fee_base_msat,
1038 proportional_millionths: hint.0.fee_proportional_millionths
1041 CandidateRouteHop::OneHopBlinded { .. } =>
1042 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1046 fn effective_capacity(&self) -> EffectiveCapacity {
1048 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
1049 liquidity_msat: details.next_outbound_htlc_limit_msat,
1051 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1052 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }} =>
1053 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1054 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }} =>
1055 EffectiveCapacity::Infinite,
1056 CandidateRouteHop::Blinded { hint, .. } =>
1057 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1058 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1062 fn id(&self, channel_direction: bool /* src_node_id < target_node_id */) -> CandidateHopId {
1064 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1065 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1066 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), channel_direction)),
1069 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1071 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1079 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1080 enum CandidateHopId {
1081 /// Contains (scid, src_node_id < target_node_id)
1083 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1088 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1089 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1091 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1092 EffectiveCapacity::Infinite => u64::max_value(),
1093 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1094 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1095 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1096 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1097 // expected to have been generated from up-to-date capacity information.
1098 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1099 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1100 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1104 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1105 -> bool where I1::Item: PartialEq<I2::Item> {
1107 let a = iter_a.next();
1108 let b = iter_b.next();
1109 if a.is_none() && b.is_none() { return true; }
1110 if a.is_none() || b.is_none() { return false; }
1111 if a.unwrap().ne(&b.unwrap()) { return false; }
1115 /// It's useful to keep track of the hops associated with the fees required to use them,
1116 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1117 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1118 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1120 struct PathBuildingHop<'a> {
1121 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
1122 // is a larger refactor and will require careful performance analysis.
1124 candidate: CandidateRouteHop<'a>,
1127 /// All the fees paid *after* this channel on the way to the destination
1128 next_hops_fee_msat: u64,
1129 /// Fee paid for the use of the current channel (see candidate.fees()).
1130 /// The value will be actually deducted from the counterparty balance on the previous link.
1131 hop_use_fee_msat: u64,
1132 /// Used to compare channels when choosing the for routing.
1133 /// Includes paying for the use of a hop and the following hops, as well as
1134 /// an estimated cost of reaching this hop.
1135 /// Might get stale when fees are recomputed. Primarily for internal use.
1136 total_fee_msat: u64,
1137 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1138 /// walk and may be invalid thereafter.
1139 path_htlc_minimum_msat: u64,
1140 /// All penalties incurred from this channel on the way to the destination, as calculated using
1141 /// channel scoring.
1142 path_penalty_msat: u64,
1143 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1144 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1145 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1146 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1147 /// avoid processing them again.
1148 was_processed: bool,
1149 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1150 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1151 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1152 // value_contribution_msat, which requires tracking it here. See comments below where it is
1153 // used for more info.
1154 value_contribution_msat: u64,
1157 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1158 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1159 let mut debug_struct = f.debug_struct("PathBuildingHop");
1161 .field("node_id", &self.node_id)
1162 .field("short_channel_id", &self.candidate.short_channel_id())
1163 .field("total_fee_msat", &self.total_fee_msat)
1164 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1165 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1166 .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)))
1167 .field("path_penalty_msat", &self.path_penalty_msat)
1168 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1169 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1170 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1171 let debug_struct = debug_struct
1172 .field("value_contribution_msat", &self.value_contribution_msat);
1173 debug_struct.finish()
1177 // Instantiated with a list of hops with correct data in them collected during path finding,
1178 // an instance of this struct should be further modified only via given methods.
1180 struct PaymentPath<'a> {
1181 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1184 impl<'a> PaymentPath<'a> {
1185 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1186 fn get_value_msat(&self) -> u64 {
1187 self.hops.last().unwrap().0.fee_msat
1190 fn get_path_penalty_msat(&self) -> u64 {
1191 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1194 fn get_total_fee_paid_msat(&self) -> u64 {
1195 if self.hops.len() < 1 {
1199 // Can't use next_hops_fee_msat because it gets outdated.
1200 for (i, (hop, _)) in self.hops.iter().enumerate() {
1201 if i != self.hops.len() - 1 {
1202 result += hop.fee_msat;
1208 fn get_cost_msat(&self) -> u64 {
1209 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1212 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1213 // to change fees may result in an inconsistency.
1215 // Sometimes we call this function right after constructing a path which is inconsistent in
1216 // that it the value being transferred has decreased while we were doing path finding, leading
1217 // to the fees being paid not lining up with the actual limits.
1219 // Note that this function is not aware of the available_liquidity limit, and thus does not
1220 // support increasing the value being transferred beyond what was selected during the initial
1222 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
1223 let mut total_fee_paid_msat = 0 as u64;
1224 for i in (0..self.hops.len()).rev() {
1225 let last_hop = i == self.hops.len() - 1;
1227 // For non-last-hop, this value will represent the fees paid on the current hop. It
1228 // will consist of the fees for the use of the next hop, and extra fees to match
1229 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1230 let mut cur_hop_fees_msat = 0;
1232 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1235 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1236 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1237 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1238 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1239 // set it too high just to maliciously take more fees by exploiting this
1240 // match htlc_minimum_msat logic.
1241 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1242 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1243 // Note that there is a risk that *previous hops* (those closer to us, as we go
1244 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1246 // This might make us end up with a broken route, although this should be super-rare
1247 // in practice, both because of how healthy channels look like, and how we pick
1248 // channels in add_entry.
1249 // Also, this can't be exploited more heavily than *announce a free path and fail
1251 cur_hop_transferred_amount_msat += extra_fees_msat;
1252 total_fee_paid_msat += extra_fees_msat;
1253 cur_hop_fees_msat += extra_fees_msat;
1257 // Final hop is a special case: it usually has just value_msat (by design), but also
1258 // it still could overpay for the htlc_minimum_msat.
1259 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1261 // Propagate updated fees for the use of the channels to one hop back, where they
1262 // will be actually paid (fee_msat). The last hop is handled above separately.
1263 cur_hop.fee_msat = cur_hop_fees_msat;
1266 // Fee for the use of the current hop which will be deducted on the previous hop.
1267 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1268 // this channel is free for us.
1270 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1271 cur_hop.hop_use_fee_msat = new_fee;
1272 total_fee_paid_msat += new_fee;
1274 // It should not be possible because this function is called only to reduce the
1275 // value. In that case, compute_fee was already called with the same fees for
1276 // larger amount and there was no overflow.
1285 /// Calculate the fees required to route the given amount over a channel with the given fees.
1286 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1287 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1288 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1292 /// Calculate the fees required to route the given amount over a channel with the given fees,
1293 /// saturating to [`u64::max_value`].
1294 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1295 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1296 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1297 .saturating_add(channel_fees.base_msat as u64)
1300 /// The default `features` we assume for a node in a route, when no `features` are known about that
1303 /// Default features are:
1304 /// * variable_length_onion_optional
1305 fn default_node_features() -> NodeFeatures {
1306 let mut features = NodeFeatures::empty();
1307 features.set_variable_length_onion_optional();
1311 struct LoggedPayeePubkey(Option<PublicKey>);
1312 impl fmt::Display for LoggedPayeePubkey {
1313 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1316 "payee node id ".fmt(f)?;
1320 "blinded payee".fmt(f)
1326 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1327 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1328 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1330 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1331 "blinded route hint with introduction node id ".fmt(f)?;
1332 hint.1.introduction_node_id.fmt(f)?;
1333 " and blinding point ".fmt(f)?;
1334 hint.1.blinding_point.fmt(f)
1336 CandidateRouteHop::FirstHop { .. } => {
1337 "first hop with SCID ".fmt(f)?;
1338 self.0.short_channel_id().unwrap().fmt(f)
1340 CandidateRouteHop::PrivateHop { .. } => {
1341 "route hint with SCID ".fmt(f)?;
1342 self.0.short_channel_id().unwrap().fmt(f)
1346 self.0.short_channel_id().unwrap().fmt(f)
1353 fn sort_first_hop_channels(
1354 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1355 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1357 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1358 // most like to use.
1360 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1361 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1364 // Second, because simply always sorting in descending order would always use our largest
1365 // available outbound capacity, needlessly fragmenting our available channel capacities,
1366 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1367 // which have enough, but not too much, capacity for the payment.
1369 // Available outbound balances factor in liquidity already reserved for previously found paths.
1370 channels.sort_unstable_by(|chan_a, chan_b| {
1371 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1372 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1373 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1374 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1375 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1376 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1377 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1378 // Sort in descending order
1379 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1381 // Sort in ascending order
1382 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1387 /// Finds a route from us (payer) to the given target node (payee).
1389 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1390 /// in the given [`RouteParameters::payment_params`].
1391 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1393 /// Private routing paths between a public node and the target may be included in the `payee` field
1394 /// of [`RouteParameters::payment_params`].
1396 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1397 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1398 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1400 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1401 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1402 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1406 /// Panics if first_hops contains channels without `short_channel_id`s;
1407 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1409 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1410 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1411 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1412 pub fn find_route<L: Deref, GL: Deref, S: Score>(
1413 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1414 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1415 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1416 ) -> Result<Route, LightningError>
1417 where L::Target: Logger, GL::Target: Logger {
1418 let graph_lock = network_graph.read_only();
1419 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
1420 route_params.final_value_msat, logger, scorer, score_params,
1421 random_seed_bytes)?;
1422 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1426 pub(crate) fn get_route<L: Deref, S: Score>(
1427 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
1428 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, logger: L, scorer: &S, score_params: &S::ScoreParams,
1429 _random_seed_bytes: &[u8; 32]
1430 ) -> Result<Route, LightningError>
1431 where L::Target: Logger {
1432 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1433 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1434 // so use a dummy id for this in the blinded case.
1435 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1436 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1437 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1438 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1439 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1441 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1442 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1445 if final_value_msat > MAX_VALUE_MSAT {
1446 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1449 if final_value_msat == 0 {
1450 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1453 match &payment_params.payee {
1454 Payee::Clear { route_hints, node_id, .. } => {
1455 for route in route_hints.iter() {
1456 for hop in &route.0 {
1457 if hop.src_node_id == *node_id {
1458 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1463 Payee::Blinded { route_hints, .. } => {
1464 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1465 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});
1467 for (_, blinded_path) in route_hints.iter() {
1468 if blinded_path.blinded_hops.len() == 0 {
1469 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1470 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1471 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1472 } else if blinded_path.blinded_hops.len() == 1 &&
1473 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1474 && p.introduction_node_id != blinded_path.introduction_node_id)
1476 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1481 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1482 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1483 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});
1486 // The general routing idea is the following:
1487 // 1. Fill first/last hops communicated by the caller.
1488 // 2. Attempt to construct a path from payer to payee for transferring
1489 // any ~sufficient (described later) value.
1490 // If succeed, remember which channels were used and how much liquidity they have available,
1491 // so that future paths don't rely on the same liquidity.
1492 // 3. Proceed to the next step if:
1493 // - we hit the recommended target value;
1494 // - OR if we could not construct a new path. Any next attempt will fail too.
1495 // Otherwise, repeat step 2.
1496 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1497 // (not recommended value).
1498 // 5. If yes, proceed. If not, fail routing.
1499 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1500 // transferred up to the transfer target value.
1501 // 7. Reduce the value of the last path until we are sending only the target value.
1502 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1503 // them so that we're not sending two HTLCs along the same path.
1505 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1506 // distance from the payee
1508 // We are not a faithful Dijkstra's implementation because we can change values which impact
1509 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1510 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1511 // the value we are currently attempting to send over a path, we simply reduce the value being
1512 // sent along the path for any hops after that channel. This may imply that later fees (which
1513 // we've already tabulated) are lower because a smaller value is passing through the channels
1514 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1515 // channels which were selected earlier (and which may still be used for other paths without a
1516 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1519 // One potentially problematic case for this algorithm would be if there are many
1520 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1521 // graph walking), we may never find a path which is not liquidity-limited and has lower
1522 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1523 // Because we only consider paths with at least 5% of the total value being sent, the damage
1524 // from such a case should be limited, however this could be further reduced in the future by
1525 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1526 // limits for the purposes of fee calculation.
1528 // Alternatively, we could store more detailed path information in the heap (targets, below)
1529 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1530 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1531 // and practically (as we would need to store dynamically-allocated path information in heap
1532 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1533 // results of such an algorithm would likely be biased towards lower-value paths.
1535 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1536 // outside of our current search value, running a path search more times to gather candidate
1537 // paths at different values. While this may be acceptable, further path searches may increase
1538 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1539 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1540 // the same time, remaining generic across different payment values.
1542 let network_channels = network_graph.channels();
1543 let network_nodes = network_graph.nodes();
1545 if payment_params.max_path_count == 0 {
1546 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1549 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1550 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1552 let allow_mpp = if payment_params.max_path_count == 1 {
1554 } else if payment_params.payee.supports_basic_mpp() {
1556 } else if let Some(payee) = payee_node_id_opt {
1557 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1558 |info| info.features.supports_basic_mpp()))
1561 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1562 LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
1563 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1566 // Prepare the data we'll use for payee-to-payer search by
1567 // inserting first hops suggested by the caller as targets.
1568 // Our search will then attempt to reach them while traversing from the payee node.
1569 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1570 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1571 if let Some(hops) = first_hops {
1573 if chan.get_outbound_payment_scid().is_none() {
1574 panic!("first_hops should be filled in with usable channels, not pending ones");
1576 if chan.counterparty.node_id == *our_node_pubkey {
1577 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1580 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1581 .or_insert(Vec::new())
1584 if first_hop_targets.is_empty() {
1585 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1589 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1590 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1591 // adding duplicate entries when we find a better path to a given node.
1592 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1594 // Map from node_id to information about the best current path to that node, including feerate
1596 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1598 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1599 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1600 // htlc_minimum with extra fees while still finding a cheaper path.
1601 let mut hit_minimum_limit;
1603 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1604 // We start with a path_value of the exact amount we want, and if that generates a route we may
1605 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1606 // amount we want in total across paths, selecting the best subset at the end.
1607 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1608 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1609 let mut path_value_msat = final_value_msat;
1611 // Routing Fragmentation Mitigation heuristic:
1613 // Routing fragmentation across many payment paths increases the overall routing
1614 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1615 // Taking too many smaller paths also increases the chance of payment failure.
1616 // Thus to avoid this effect, we require from our collected links to provide
1617 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1618 // This requirement is currently set to be 1/max_path_count of the payment
1619 // value to ensure we only ever return routes that do not violate this limit.
1620 let minimal_value_contribution_msat: u64 = if allow_mpp {
1621 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1626 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1627 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1628 // drop the requirement by setting this to 0.
1629 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1631 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1632 // determine if the channel can be used by additional MPP paths or to inform path finding
1633 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1634 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1636 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1637 HashMap::with_capacity(network_nodes.len());
1639 // Keeping track of how much value we already collected across other paths. Helps to decide
1640 // when we want to stop looking for new paths.
1641 let mut already_collected_value_msat = 0;
1643 for (_, channels) in first_hop_targets.iter_mut() {
1644 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1648 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1649 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1651 // Remember how many candidates we ignored to allow for some logging afterwards.
1652 let mut num_ignored_value_contribution = 0;
1653 let mut num_ignored_path_length_limit = 0;
1654 let mut num_ignored_cltv_delta_limit = 0;
1655 let mut num_ignored_previously_failed = 0;
1657 macro_rules! add_entry {
1658 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1659 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1660 // since that value has to be transferred over this channel.
1661 // Returns whether this channel caused an update to `targets`.
1662 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1663 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1664 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1665 // We "return" whether we updated the path at the end, and how much we can route via
1666 // this channel, via this:
1667 let mut did_add_update_path_to_src_node = None;
1668 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1669 // practice these cases should be caught earlier:
1670 // - for regular channels at channel announcement (TODO)
1671 // - for first and last hops early in get_route
1672 if $src_node_id != $dest_node_id {
1673 let scid_opt = $candidate.short_channel_id();
1674 let effective_capacity = $candidate.effective_capacity();
1675 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1677 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1678 // It may be misleading because we might later choose to reduce the value transferred
1679 // over these channels, and the channel which was insufficient might become sufficient.
1680 // Worst case: we drop a good channel here because it can't cover the high following
1681 // fees caused by one expensive channel, but then this channel could have been used
1682 // if the amount being transferred over this path is lower.
1683 // We do this for now, but this is a subject for removal.
1684 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1685 let used_liquidity_msat = used_liquidities
1686 .get(&$candidate.id($src_node_id < $dest_node_id))
1687 .map_or(0, |used_liquidity_msat| {
1688 available_value_contribution_msat = available_value_contribution_msat
1689 .saturating_sub(*used_liquidity_msat);
1690 *used_liquidity_msat
1693 // Verify the liquidity offered by this channel complies to the minimal contribution.
1694 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1695 // Do not consider candidate hops that would exceed the maximum path length.
1696 let path_length_to_node = $next_hops_path_length + 1;
1697 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1699 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1700 // In order to already account for some of the privacy enhancing random CLTV
1701 // expiry delta offset we add on top later, we subtract a rough estimate
1702 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1703 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1704 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1705 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1706 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1707 .saturating_add($candidate.cltv_expiry_delta());
1708 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1710 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1711 // Includes paying fees for the use of the following channels.
1712 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1713 Some(result) => result,
1714 // Can't overflow due to how the values were computed right above.
1715 None => unreachable!(),
1717 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1718 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1719 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1721 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1722 let may_overpay_to_meet_path_minimum_msat =
1723 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1724 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1725 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1726 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1728 let payment_failed_on_this_channel = scid_opt.map_or(false,
1729 |scid| payment_params.previously_failed_channels.contains(&scid));
1731 let should_log_candidate = match $candidate {
1732 CandidateRouteHop::FirstHop { .. } => true,
1733 CandidateRouteHop::PrivateHop { .. } => true,
1734 CandidateRouteHop::Blinded { .. } => true,
1738 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1739 // bother considering this channel. If retrying with recommended_value_msat may
1740 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1741 // around again with a higher amount.
1742 if !contributes_sufficient_value {
1743 if should_log_candidate {
1744 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1746 num_ignored_value_contribution += 1;
1747 } else if exceeds_max_path_length {
1748 if should_log_candidate {
1749 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1751 num_ignored_path_length_limit += 1;
1752 } else if exceeds_cltv_delta_limit {
1753 if should_log_candidate {
1754 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1756 num_ignored_cltv_delta_limit += 1;
1757 } else if payment_failed_on_this_channel {
1758 if should_log_candidate {
1759 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1761 num_ignored_previously_failed += 1;
1762 } else if may_overpay_to_meet_path_minimum_msat {
1763 hit_minimum_limit = true;
1764 } else if over_path_minimum_msat {
1765 // Note that low contribution here (limited by available_liquidity_msat)
1766 // might violate htlc_minimum_msat on the hops which are next along the
1767 // payment path (upstream to the payee). To avoid that, we recompute
1768 // path fees knowing the final path contribution after constructing it.
1769 let path_htlc_minimum_msat = cmp::max(
1770 compute_fees_saturating($next_hops_path_htlc_minimum_msat, $candidate.fees())
1771 .saturating_add($next_hops_path_htlc_minimum_msat),
1772 $candidate.htlc_minimum_msat());
1773 let hm_entry = dist.entry($src_node_id);
1774 let old_entry = hm_entry.or_insert_with(|| {
1775 // If there was previously no known way to access the source node
1776 // (recall it goes payee-to-payer) of short_channel_id, first add a
1777 // semi-dummy record just to compute the fees to reach the source node.
1778 // This will affect our decision on selecting short_channel_id
1779 // as a way to reach the $dest_node_id.
1781 node_id: $dest_node_id.clone(),
1782 candidate: $candidate.clone(),
1784 next_hops_fee_msat: u64::max_value(),
1785 hop_use_fee_msat: u64::max_value(),
1786 total_fee_msat: u64::max_value(),
1787 path_htlc_minimum_msat,
1788 path_penalty_msat: u64::max_value(),
1789 was_processed: false,
1790 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1791 value_contribution_msat,
1795 #[allow(unused_mut)] // We only use the mut in cfg(test)
1796 let mut should_process = !old_entry.was_processed;
1797 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1799 // In test/fuzzing builds, we do extra checks to make sure the skipping
1800 // of already-seen nodes only happens in cases we expect (see below).
1801 if !should_process { should_process = true; }
1805 let mut hop_use_fee_msat = 0;
1806 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1808 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1809 // will have the same effective-fee
1810 if $src_node_id != our_node_id {
1811 // Note that `u64::max_value` means we'll always fail the
1812 // `old_entry.total_fee_msat > total_fee_msat` check below
1813 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1814 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1817 let channel_usage = ChannelUsage {
1818 amount_msat: amount_to_transfer_over_msat,
1819 inflight_htlc_msat: used_liquidity_msat,
1822 let channel_penalty_msat = scid_opt.map_or(0,
1823 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1824 channel_usage, score_params));
1825 let path_penalty_msat = $next_hops_path_penalty_msat
1826 .saturating_add(channel_penalty_msat);
1827 let new_graph_node = RouteGraphNode {
1828 node_id: $src_node_id,
1829 lowest_fee_to_node: total_fee_msat,
1830 total_cltv_delta: hop_total_cltv_delta,
1831 value_contribution_msat,
1832 path_htlc_minimum_msat,
1834 path_length_to_node,
1837 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1838 // if this way is cheaper than the already known
1839 // (considering the cost to "reach" this channel from the route destination,
1840 // the cost of using this channel,
1841 // and the cost of routing to the source node of this channel).
1842 // Also, consider that htlc_minimum_msat_difference, because we might end up
1843 // paying it. Consider the following exploit:
1844 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1845 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1846 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1847 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1849 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1850 // but it may require additional tracking - we don't want to double-count
1851 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1852 // can't use something that may decrease on future hops.
1853 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1854 .saturating_add(old_entry.path_penalty_msat);
1855 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1856 .saturating_add(path_penalty_msat);
1858 if !old_entry.was_processed && new_cost < old_cost {
1859 targets.push(new_graph_node);
1860 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1861 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1862 old_entry.total_fee_msat = total_fee_msat;
1863 old_entry.node_id = $dest_node_id.clone();
1864 old_entry.candidate = $candidate.clone();
1865 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1866 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1867 old_entry.path_penalty_msat = path_penalty_msat;
1868 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1870 old_entry.value_contribution_msat = value_contribution_msat;
1872 did_add_update_path_to_src_node = Some(value_contribution_msat);
1873 } else if old_entry.was_processed && new_cost < old_cost {
1874 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1876 // If we're skipping processing a node which was previously
1877 // processed even though we found another path to it with a
1878 // cheaper fee, check that it was because the second path we
1879 // found (which we are processing now) has a lower value
1880 // contribution due to an HTLC minimum limit.
1882 // e.g. take a graph with two paths from node 1 to node 2, one
1883 // through channel A, and one through channel B. Channel A and
1884 // B are both in the to-process heap, with their scores set by
1885 // a higher htlc_minimum than fee.
1886 // Channel A is processed first, and the channels onwards from
1887 // node 1 are added to the to-process heap. Thereafter, we pop
1888 // Channel B off of the heap, note that it has a much more
1889 // restrictive htlc_maximum_msat, and recalculate the fees for
1890 // all of node 1's channels using the new, reduced, amount.
1892 // This would be bogus - we'd be selecting a higher-fee path
1893 // with a lower htlc_maximum_msat instead of the one we'd
1894 // already decided to use.
1895 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1897 value_contribution_msat + path_penalty_msat <
1898 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1906 did_add_update_path_to_src_node
1910 let default_node_features = default_node_features();
1912 // Find ways (channels with destination) to reach a given node and store them
1913 // in the corresponding data structures (routing graph etc).
1914 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1915 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1916 // This data can later be helpful to optimize routing (pay lower fees).
1917 macro_rules! add_entries_to_cheapest_to_target_node {
1918 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1919 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1920 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1921 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1922 let was_processed = elem.was_processed;
1923 elem.was_processed = true;
1926 // Entries are added to dist in add_entry!() when there is a channel from a node.
1927 // Because there are no channels from payee, it will not have a dist entry at this point.
1928 // If we're processing any other node, it is always be the result of a channel from it.
1929 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
1934 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1935 for details in first_channels {
1936 let candidate = CandidateRouteHop::FirstHop { details };
1937 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1938 $next_hops_value_contribution,
1939 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1940 $next_hops_cltv_delta, $next_hops_path_length);
1944 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1947 &default_node_features
1950 if !features.requires_unknown_bits() {
1951 for chan_id in $node.channels.iter() {
1952 let chan = network_channels.get(chan_id).unwrap();
1953 if !chan.features.requires_unknown_bits() {
1954 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1955 if first_hops.is_none() || *source != our_node_id {
1956 if directed_channel.direction().enabled {
1957 let candidate = CandidateRouteHop::PublicHop {
1958 info: directed_channel,
1959 short_channel_id: *chan_id,
1961 add_entry!(candidate, *source, $node_id,
1962 $fee_to_target_msat,
1963 $next_hops_value_contribution,
1964 $next_hops_path_htlc_minimum_msat,
1965 $next_hops_path_penalty_msat,
1966 $next_hops_cltv_delta, $next_hops_path_length);
1977 let mut payment_paths = Vec::<PaymentPath>::new();
1979 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1980 'paths_collection: loop {
1981 // For every new path, start from scratch, except for used_liquidities, which
1982 // helps to avoid reusing previously selected paths in future iterations.
1985 hit_minimum_limit = false;
1987 // If first hop is a private channel and the only way to reach the payee, this is the only
1988 // place where it could be added.
1989 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
1990 for details in first_channels {
1991 let candidate = CandidateRouteHop::FirstHop { details };
1992 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
1993 0, 0u64, 0, 0).is_some();
1994 log_trace!(logger, "{} direct route to payee via {}",
1995 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
1999 // Add the payee as a target, so that the payee-to-payer
2000 // search algorithm knows what to start with.
2001 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2002 // The payee is not in our network graph, so nothing to add here.
2003 // There is still a chance of reaching them via last_hops though,
2004 // so don't yet fail the payment here.
2005 // If not, targets.pop() will not even let us enter the loop in step 2.
2008 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2013 // If a caller provided us with last hops, add them to routing targets. Since this happens
2014 // earlier than general path finding, they will be somewhat prioritized, although currently
2015 // it matters only if the fees are exactly the same.
2016 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2017 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2018 let have_intro_node_in_graph =
2019 // Only add the hops in this route to our candidate set if either
2020 // we have a direct channel to the first hop or the first hop is
2021 // in the regular network graph.
2022 first_hop_targets.get(&intro_node_id).is_some() ||
2023 network_nodes.get(&intro_node_id).is_some();
2024 if !have_intro_node_in_graph { continue }
2025 let candidate = if hint.1.blinded_hops.len() == 1 {
2026 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2027 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2028 let mut path_contribution_msat = path_value_msat;
2029 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2030 0, path_contribution_msat, 0, 0_u64, 0, 0)
2032 path_contribution_msat = hop_used_msat;
2034 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2035 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2037 for details in first_channels {
2038 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2039 add_entry!(first_hop_candidate, our_node_id, intro_node_id, 0, path_contribution_msat, 0,
2044 for route in payment_params.payee.unblinded_route_hints().iter()
2045 .filter(|route| !route.0.is_empty())
2047 let first_hop_in_route = &(route.0)[0];
2048 let have_hop_src_in_graph =
2049 // Only add the hops in this route to our candidate set if either
2050 // we have a direct channel to the first hop or the first hop is
2051 // in the regular network graph.
2052 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
2053 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
2054 if have_hop_src_in_graph {
2055 // We start building the path from reverse, i.e., from payee
2056 // to the first RouteHintHop in the path.
2057 let hop_iter = route.0.iter().rev();
2058 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2059 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2060 let mut hop_used = true;
2061 let mut aggregate_next_hops_fee_msat: u64 = 0;
2062 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2063 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2064 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2065 let mut aggregate_next_hops_path_length: u8 = 0;
2066 let mut aggregate_path_contribution_msat = path_value_msat;
2068 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2069 let source = NodeId::from_pubkey(&hop.src_node_id);
2070 let target = NodeId::from_pubkey(&prev_hop_id);
2071 let candidate = network_channels
2072 .get(&hop.short_channel_id)
2073 .and_then(|channel| channel.as_directed_to(&target))
2074 .map(|(info, _)| CandidateRouteHop::PublicHop {
2076 short_channel_id: hop.short_channel_id,
2078 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2080 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2081 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2082 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2083 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2085 aggregate_path_contribution_msat = hop_used_msat;
2087 // If this hop was not used then there is no use checking the preceding
2088 // hops in the RouteHint. We can break by just searching for a direct
2089 // channel between last checked hop and first_hop_targets.
2093 let used_liquidity_msat = used_liquidities
2094 .get(&candidate.id(source < target)).copied()
2096 let channel_usage = ChannelUsage {
2097 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2098 inflight_htlc_msat: used_liquidity_msat,
2099 effective_capacity: candidate.effective_capacity(),
2101 let channel_penalty_msat = scorer.channel_penalty_msat(
2102 hop.short_channel_id, &source, &target, channel_usage, score_params
2104 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2105 .saturating_add(channel_penalty_msat);
2107 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2108 .saturating_add(hop.cltv_expiry_delta as u32);
2110 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2113 // Searching for a direct channel between last checked hop and first_hop_targets
2114 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&prev_hop_id)) {
2115 sort_first_hop_channels(first_channels, &used_liquidities,
2116 recommended_value_msat, our_node_pubkey);
2117 for details in first_channels {
2118 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2119 add_entry!(first_hop_candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
2120 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2121 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2122 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2130 // In the next values of the iterator, the aggregate fees already reflects
2131 // the sum of value sent from payer (final_value_msat) and routing fees
2132 // for the last node in the RouteHint. We need to just add the fees to
2133 // route through the current node so that the preceding node (next iteration)
2135 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2136 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2137 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2139 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
2140 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
2141 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
2142 .checked_add(hop_htlc_minimum_msat_inc);
2143 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
2145 if idx == route.0.len() - 1 {
2146 // The last hop in this iterator is the first hop in
2147 // overall RouteHint.
2148 // If this hop connects to a node with which we have a direct channel,
2149 // ignore the network graph and, if the last hop was added, add our
2150 // direct channel to the candidate set.
2152 // Note that we *must* check if the last hop was added as `add_entry`
2153 // always assumes that the third argument is a node to which we have a
2155 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2156 sort_first_hop_channels(first_channels, &used_liquidities,
2157 recommended_value_msat, our_node_pubkey);
2158 for details in first_channels {
2159 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2160 add_entry!(first_hop_candidate, our_node_id,
2161 NodeId::from_pubkey(&hop.src_node_id),
2162 aggregate_next_hops_fee_msat,
2163 aggregate_path_contribution_msat,
2164 aggregate_next_hops_path_htlc_minimum_msat,
2165 aggregate_next_hops_path_penalty_msat,
2166 aggregate_next_hops_cltv_delta,
2167 aggregate_next_hops_path_length);
2175 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2177 // At this point, targets are filled with the data from first and
2178 // last hops communicated by the caller, and the payment receiver.
2179 let mut found_new_path = false;
2182 // If this loop terminates due the exhaustion of targets, two situations are possible:
2183 // - not enough outgoing liquidity:
2184 // 0 < already_collected_value_msat < final_value_msat
2185 // - enough outgoing liquidity:
2186 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2187 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2188 // paths_collection will be stopped because found_new_path==false.
2189 // This is not necessarily a routing failure.
2190 '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() {
2192 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2193 // traversing the graph and arrange the path out of what we found.
2194 if node_id == our_node_id {
2195 let mut new_entry = dist.remove(&our_node_id).unwrap();
2196 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2199 let mut features_set = false;
2200 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2201 for details in first_channels {
2202 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2203 if details.get_outbound_payment_scid().unwrap() == scid {
2204 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2205 features_set = true;
2212 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2213 if let Some(node_info) = node.announcement_info.as_ref() {
2214 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2216 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2219 // We can fill in features for everything except hops which were
2220 // provided via the invoice we're paying. We could guess based on the
2221 // recipient's features but for now we simply avoid guessing at all.
2225 // Means we succesfully traversed from the payer to the payee, now
2226 // save this path for the payment route. Also, update the liquidity
2227 // remaining on the used hops, so that we take them into account
2228 // while looking for more paths.
2229 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2233 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2234 Some(payment_hop) => payment_hop,
2235 // We can't arrive at None because, if we ever add an entry to targets,
2236 // we also fill in the entry in dist (see add_entry!).
2237 None => unreachable!(),
2239 // We "propagate" the fees one hop backward (topologically) here,
2240 // so that fees paid for a HTLC forwarding on the current channel are
2241 // associated with the previous channel (where they will be subtracted).
2242 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2243 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2245 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2246 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2248 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2249 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2251 let mut payment_path = PaymentPath {hops: ordered_hops};
2253 // We could have possibly constructed a slightly inconsistent path: since we reduce
2254 // value being transferred along the way, we could have violated htlc_minimum_msat
2255 // on some channels we already passed (assuming dest->source direction). Here, we
2256 // recompute the fees again, so that if that's the case, we match the currently
2257 // underpaid htlc_minimum_msat with fees.
2258 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2259 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
2260 payment_path.update_value_and_recompute_fees(value_contribution_msat);
2262 // Since a path allows to transfer as much value as
2263 // the smallest channel it has ("bottleneck"), we should recompute
2264 // the fees so sender HTLC don't overpay fees when traversing
2265 // larger channels than the bottleneck. This may happen because
2266 // when we were selecting those channels we were not aware how much value
2267 // this path will transfer, and the relative fee for them
2268 // might have been computed considering a larger value.
2269 // Remember that we used these channels so that we don't rely
2270 // on the same liquidity in future paths.
2271 let mut prevented_redundant_path_selection = false;
2272 let prev_hop_iter = core::iter::once(&our_node_id)
2273 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2274 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2275 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2276 let used_liquidity_msat = used_liquidities
2277 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2278 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2279 .or_insert(spent_on_hop_msat);
2280 let hop_capacity = hop.candidate.effective_capacity();
2281 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2282 if *used_liquidity_msat == hop_max_msat {
2283 // If this path used all of this channel's available liquidity, we know
2284 // this path will not be selected again in the next loop iteration.
2285 prevented_redundant_path_selection = true;
2287 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2289 if !prevented_redundant_path_selection {
2290 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2291 // we'll probably end up picking the same path again on the next iteration.
2292 // Decrease the available liquidity of a hop in the middle of the path.
2293 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2294 let exhausted = u64::max_value();
2295 log_trace!(logger, "Disabling route candidate {} for future path building iterations to
2296 avoid duplicates.", LoggedCandidateHop(victim_candidate));
2297 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2298 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2301 // Track the total amount all our collected paths allow to send so that we know
2302 // when to stop looking for more paths
2303 already_collected_value_msat += value_contribution_msat;
2305 payment_paths.push(payment_path);
2306 found_new_path = true;
2307 break 'path_construction;
2310 // If we found a path back to the payee, we shouldn't try to process it again. This is
2311 // the equivalent of the `elem.was_processed` check in
2312 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2313 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2315 // Otherwise, since the current target node is not us,
2316 // keep "unrolling" the payment graph from payee to payer by
2317 // finding a way to reach the current target from the payer side.
2318 match network_nodes.get(&node_id) {
2321 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2322 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2323 total_cltv_delta, path_length_to_node);
2329 if !found_new_path && channel_saturation_pow_half != 0 {
2330 channel_saturation_pow_half = 0;
2331 continue 'paths_collection;
2333 // If we don't support MPP, no use trying to gather more value ever.
2334 break 'paths_collection;
2338 // Stop either when the recommended value is reached or if no new path was found in this
2340 // In the latter case, making another path finding attempt won't help,
2341 // because we deterministically terminated the search due to low liquidity.
2342 if !found_new_path && channel_saturation_pow_half != 0 {
2343 channel_saturation_pow_half = 0;
2344 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2345 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2346 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2347 break 'paths_collection;
2348 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2349 // Further, if this was our first walk of the graph, and we weren't limited by an
2350 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2351 // limited by an htlc_minimum_msat value, find another path with a higher value,
2352 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2353 // still keeping a lower total fee than this path.
2354 if !hit_minimum_limit {
2355 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2356 break 'paths_collection;
2358 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
2359 path_value_msat = recommended_value_msat;
2363 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2364 num_ignored_cltv_delta_limit + num_ignored_previously_failed;
2365 if num_ignored_total > 0 {
2366 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);
2370 if payment_paths.len() == 0 {
2371 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2374 if already_collected_value_msat < final_value_msat {
2375 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2379 let mut selected_route = payment_paths;
2381 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2382 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2384 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2385 // the value they contribute towards the payment amount.
2386 // We sort in descending order as we will remove from the front in `retain`, next.
2387 selected_route.sort_unstable_by(|a, b|
2388 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2389 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2392 // We should make sure that at least 1 path left.
2393 let mut paths_left = selected_route.len();
2394 selected_route.retain(|path| {
2395 if paths_left == 1 {
2398 let path_value_msat = path.get_value_msat();
2399 if path_value_msat <= overpaid_value_msat {
2400 overpaid_value_msat -= path_value_msat;
2406 debug_assert!(selected_route.len() > 0);
2408 if overpaid_value_msat != 0 {
2410 // Now, subtract the remaining overpaid value from the most-expensive path.
2411 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2412 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2413 selected_route.sort_unstable_by(|a, b| {
2414 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2415 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2416 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2418 let expensive_payment_path = selected_route.first_mut().unwrap();
2420 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2421 // can't go negative.
2422 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2423 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2427 // Sort by the path itself and combine redundant paths.
2428 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2429 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2431 selected_route.sort_unstable_by_key(|path| {
2432 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2433 debug_assert!(path.hops.len() <= key.len());
2434 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2439 for idx in 0..(selected_route.len() - 1) {
2440 if idx + 1 >= selected_route.len() { break; }
2441 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2442 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2443 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2444 selected_route[idx].update_value_and_recompute_fees(new_value);
2445 selected_route.remove(idx + 1);
2449 let mut paths = Vec::new();
2450 for payment_path in selected_route {
2451 let mut hops = Vec::with_capacity(payment_path.hops.len());
2452 for (hop, node_features) in payment_path.hops.iter()
2453 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2455 hops.push(RouteHop {
2456 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)})?,
2457 node_features: node_features.clone(),
2458 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2459 channel_features: hop.candidate.features(),
2460 fee_msat: hop.fee_msat,
2461 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2464 let mut final_cltv_delta = final_cltv_expiry_delta;
2465 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2466 if let Some(blinded_path) = h.candidate.blinded_path() {
2467 final_cltv_delta = h.candidate.cltv_expiry_delta();
2469 hops: blinded_path.blinded_hops.clone(),
2470 blinding_point: blinded_path.blinding_point,
2471 excess_final_cltv_expiry_delta: 0,
2472 final_value_msat: h.fee_msat,
2476 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2477 // applicable for the previous hop.
2478 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2479 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2482 paths.push(Path { hops, blinded_tail });
2484 // Make sure we would never create a route with more paths than we allow.
2485 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2487 if let Some(node_features) = payment_params.payee.node_features() {
2488 for path in paths.iter_mut() {
2489 path.hops.last_mut().unwrap().node_features = node_features.clone();
2493 let route = Route { paths, payment_params: Some(payment_params.clone()) };
2494 log_info!(logger, "Got route: {}", log_route!(route));
2498 // When an adversarial intermediary node observes a payment, it may be able to infer its
2499 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2500 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2501 // payment path by adding a randomized 'shadow route' offset to the final hop.
2502 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2503 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2505 let network_channels = network_graph.channels();
2506 let network_nodes = network_graph.nodes();
2508 for path in route.paths.iter_mut() {
2509 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2511 // Remember the last three nodes of the random walk and avoid looping back on them.
2512 // Init with the last three nodes from the actual path, if possible.
2513 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2514 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2515 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2517 // Choose the last publicly known node as the starting point for the random walk.
2518 let mut cur_hop: Option<NodeId> = None;
2519 let mut path_nonce = [0u8; 12];
2520 if let Some(starting_hop) = path.hops.iter().rev()
2521 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2522 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2523 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2526 // Init PRNG with the path-dependant nonce, which is static for private paths.
2527 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2528 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2530 // Pick a random path length in [1 .. 3]
2531 prng.process_in_place(&mut random_path_bytes);
2532 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2534 for random_hop in 0..random_walk_length {
2535 // If we don't find a suitable offset in the public network graph, we default to
2536 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2537 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2539 if let Some(cur_node_id) = cur_hop {
2540 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2541 // Randomly choose the next unvisited hop.
2542 prng.process_in_place(&mut random_path_bytes);
2543 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2544 .checked_rem(cur_node.channels.len())
2545 .and_then(|index| cur_node.channels.get(index))
2546 .and_then(|id| network_channels.get(id)) {
2547 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2548 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2549 nodes_to_avoid[random_hop] = *next_id;
2550 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2551 cur_hop = Some(*next_id);
2558 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2559 .checked_add(random_hop_offset)
2560 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2563 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2564 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2565 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2567 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2568 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2569 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2570 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2571 max_path_offset = cmp::max(
2572 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2573 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2574 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2576 // Add 'shadow' CLTV offset to the final hop
2577 if let Some(tail) = path.blinded_tail.as_mut() {
2578 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2579 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2581 if let Some(last_hop) = path.hops.last_mut() {
2582 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2583 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2588 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2589 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2591 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2592 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2593 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2594 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2595 ) -> Result<Route, LightningError>
2596 where L::Target: Logger, GL::Target: Logger {
2597 let graph_lock = network_graph.read_only();
2598 let mut route = build_route_from_hops_internal(
2599 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
2600 route_params.final_value_msat, logger, random_seed_bytes)?;
2601 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2605 fn build_route_from_hops_internal<L: Deref>(
2606 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
2607 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, logger: L,
2608 random_seed_bytes: &[u8; 32]
2609 ) -> Result<Route, LightningError> where L::Target: Logger {
2612 our_node_id: NodeId,
2613 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2616 impl Score for HopScorer {
2617 type ScoreParams = ();
2618 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2619 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2621 let mut cur_id = self.our_node_id;
2622 for i in 0..self.hop_ids.len() {
2623 if let Some(next_id) = self.hop_ids[i] {
2624 if cur_id == *source && next_id == *target {
2635 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
2637 fn payment_path_successful(&mut self, _path: &Path) {}
2639 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
2641 fn probe_successful(&mut self, _path: &Path) {}
2644 impl<'a> Writeable for HopScorer {
2646 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2651 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2652 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2655 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2656 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2657 for i in 0..hops.len() {
2658 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2661 let scorer = HopScorer { our_node_id, hop_ids };
2663 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
2664 logger, &scorer, &(), random_seed_bytes)
2669 use crate::blinded_path::{BlindedHop, BlindedPath};
2670 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2671 use crate::routing::utxo::UtxoResult;
2672 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2673 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2674 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
2675 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, Score, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2676 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2677 use crate::chain::transaction::OutPoint;
2678 use crate::sign::EntropySource;
2679 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2680 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2681 use crate::ln::channelmanager;
2682 use crate::offers::invoice::BlindedPayInfo;
2683 use crate::util::config::UserConfig;
2684 use crate::util::test_utils as ln_test_utils;
2685 use crate::util::chacha20::ChaCha20;
2686 use crate::util::ser::{Readable, Writeable};
2688 use crate::util::ser::Writer;
2690 use bitcoin::hashes::Hash;
2691 use bitcoin::network::constants::Network;
2692 use bitcoin::blockdata::constants::genesis_block;
2693 use bitcoin::blockdata::script::Builder;
2694 use bitcoin::blockdata::opcodes;
2695 use bitcoin::blockdata::transaction::TxOut;
2699 use bitcoin::secp256k1::{PublicKey,SecretKey};
2700 use bitcoin::secp256k1::Secp256k1;
2702 use crate::io::Cursor;
2703 use crate::prelude::*;
2704 use crate::sync::Arc;
2706 use core::convert::TryInto;
2708 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2709 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2710 channelmanager::ChannelDetails {
2711 channel_id: [0; 32],
2712 counterparty: channelmanager::ChannelCounterparty {
2715 unspendable_punishment_reserve: 0,
2716 forwarding_info: None,
2717 outbound_htlc_minimum_msat: None,
2718 outbound_htlc_maximum_msat: None,
2720 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2723 outbound_scid_alias: None,
2724 inbound_scid_alias: None,
2725 channel_value_satoshis: 0,
2728 outbound_capacity_msat,
2729 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2730 next_outbound_htlc_minimum_msat: 0,
2731 inbound_capacity_msat: 42,
2732 unspendable_punishment_reserve: None,
2733 confirmations_required: None,
2734 confirmations: None,
2735 force_close_spend_delay: None,
2736 is_outbound: true, is_channel_ready: true,
2737 is_usable: true, is_public: true,
2738 inbound_htlc_minimum_msat: None,
2739 inbound_htlc_maximum_msat: None,
2741 feerate_sat_per_1000_weight: None,
2742 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2747 fn simple_route_test() {
2748 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2749 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2750 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2751 let scorer = ln_test_utils::TestScorer::new();
2752 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2753 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2755 // Simple route to 2 via 1
2757 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 0, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2758 assert_eq!(err, "Cannot send a payment of 0 msat");
2759 } else { panic!(); }
2761 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2762 assert_eq!(route.paths[0].hops.len(), 2);
2764 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2765 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2766 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2767 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2768 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2769 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2771 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2772 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2773 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2774 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2775 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2776 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2780 fn invalid_first_hop_test() {
2781 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2782 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2783 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2784 let scorer = ln_test_utils::TestScorer::new();
2785 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2786 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2788 // Simple route to 2 via 1
2790 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2792 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2793 get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2794 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2795 } else { panic!(); }
2797 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2798 assert_eq!(route.paths[0].hops.len(), 2);
2802 fn htlc_minimum_test() {
2803 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2804 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2805 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2806 let scorer = ln_test_utils::TestScorer::new();
2807 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2808 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2810 // Simple route to 2 via 1
2812 // Disable other paths
2813 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2814 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2815 short_channel_id: 12,
2817 flags: 2, // to disable
2818 cltv_expiry_delta: 0,
2819 htlc_minimum_msat: 0,
2820 htlc_maximum_msat: MAX_VALUE_MSAT,
2822 fee_proportional_millionths: 0,
2823 excess_data: Vec::new()
2825 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2826 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2827 short_channel_id: 3,
2829 flags: 2, // to disable
2830 cltv_expiry_delta: 0,
2831 htlc_minimum_msat: 0,
2832 htlc_maximum_msat: MAX_VALUE_MSAT,
2834 fee_proportional_millionths: 0,
2835 excess_data: Vec::new()
2837 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2838 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2839 short_channel_id: 13,
2841 flags: 2, // to disable
2842 cltv_expiry_delta: 0,
2843 htlc_minimum_msat: 0,
2844 htlc_maximum_msat: MAX_VALUE_MSAT,
2846 fee_proportional_millionths: 0,
2847 excess_data: Vec::new()
2849 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2850 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2851 short_channel_id: 6,
2853 flags: 2, // to disable
2854 cltv_expiry_delta: 0,
2855 htlc_minimum_msat: 0,
2856 htlc_maximum_msat: MAX_VALUE_MSAT,
2858 fee_proportional_millionths: 0,
2859 excess_data: Vec::new()
2861 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2862 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2863 short_channel_id: 7,
2865 flags: 2, // to disable
2866 cltv_expiry_delta: 0,
2867 htlc_minimum_msat: 0,
2868 htlc_maximum_msat: MAX_VALUE_MSAT,
2870 fee_proportional_millionths: 0,
2871 excess_data: Vec::new()
2874 // Check against amount_to_transfer_over_msat.
2875 // Set minimal HTLC of 200_000_000 msat.
2876 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2877 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2878 short_channel_id: 2,
2881 cltv_expiry_delta: 0,
2882 htlc_minimum_msat: 200_000_000,
2883 htlc_maximum_msat: MAX_VALUE_MSAT,
2885 fee_proportional_millionths: 0,
2886 excess_data: Vec::new()
2889 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2891 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2892 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2893 short_channel_id: 4,
2896 cltv_expiry_delta: 0,
2897 htlc_minimum_msat: 0,
2898 htlc_maximum_msat: 199_999_999,
2900 fee_proportional_millionths: 0,
2901 excess_data: Vec::new()
2904 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2905 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
2906 assert_eq!(err, "Failed to find a path to the given destination");
2907 } else { panic!(); }
2909 // Lift the restriction on the first hop.
2910 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2911 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2912 short_channel_id: 2,
2915 cltv_expiry_delta: 0,
2916 htlc_minimum_msat: 0,
2917 htlc_maximum_msat: MAX_VALUE_MSAT,
2919 fee_proportional_millionths: 0,
2920 excess_data: Vec::new()
2923 // A payment above the minimum should pass
2924 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
2925 assert_eq!(route.paths[0].hops.len(), 2);
2929 fn htlc_minimum_overpay_test() {
2930 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2931 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2932 let config = UserConfig::default();
2933 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
2934 let scorer = ln_test_utils::TestScorer::new();
2935 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2936 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2938 // A route to node#2 via two paths.
2939 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2940 // Thus, they can't send 60 without overpaying.
2941 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2942 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2943 short_channel_id: 2,
2946 cltv_expiry_delta: 0,
2947 htlc_minimum_msat: 35_000,
2948 htlc_maximum_msat: 40_000,
2950 fee_proportional_millionths: 0,
2951 excess_data: Vec::new()
2953 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2954 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2955 short_channel_id: 12,
2958 cltv_expiry_delta: 0,
2959 htlc_minimum_msat: 35_000,
2960 htlc_maximum_msat: 40_000,
2962 fee_proportional_millionths: 0,
2963 excess_data: Vec::new()
2967 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2968 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2969 short_channel_id: 13,
2972 cltv_expiry_delta: 0,
2973 htlc_minimum_msat: 0,
2974 htlc_maximum_msat: MAX_VALUE_MSAT,
2976 fee_proportional_millionths: 0,
2977 excess_data: Vec::new()
2979 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2980 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2981 short_channel_id: 4,
2984 cltv_expiry_delta: 0,
2985 htlc_minimum_msat: 0,
2986 htlc_maximum_msat: MAX_VALUE_MSAT,
2988 fee_proportional_millionths: 0,
2989 excess_data: Vec::new()
2992 // Disable other paths
2993 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2994 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2995 short_channel_id: 1,
2997 flags: 2, // to disable
2998 cltv_expiry_delta: 0,
2999 htlc_minimum_msat: 0,
3000 htlc_maximum_msat: MAX_VALUE_MSAT,
3002 fee_proportional_millionths: 0,
3003 excess_data: Vec::new()
3006 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3007 // Overpay fees to hit htlc_minimum_msat.
3008 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3009 // TODO: this could be better balanced to overpay 10k and not 15k.
3010 assert_eq!(overpaid_fees, 15_000);
3012 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3013 // while taking even more fee to match htlc_minimum_msat.
3014 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3015 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3016 short_channel_id: 12,
3019 cltv_expiry_delta: 0,
3020 htlc_minimum_msat: 65_000,
3021 htlc_maximum_msat: 80_000,
3023 fee_proportional_millionths: 0,
3024 excess_data: Vec::new()
3026 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3027 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3028 short_channel_id: 2,
3031 cltv_expiry_delta: 0,
3032 htlc_minimum_msat: 0,
3033 htlc_maximum_msat: MAX_VALUE_MSAT,
3035 fee_proportional_millionths: 0,
3036 excess_data: Vec::new()
3038 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3039 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3040 short_channel_id: 4,
3043 cltv_expiry_delta: 0,
3044 htlc_minimum_msat: 0,
3045 htlc_maximum_msat: MAX_VALUE_MSAT,
3047 fee_proportional_millionths: 100_000,
3048 excess_data: Vec::new()
3051 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3052 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3053 assert_eq!(route.paths.len(), 1);
3054 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3055 let fees = route.paths[0].hops[0].fee_msat;
3056 assert_eq!(fees, 5_000);
3058 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3059 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3060 // the other channel.
3061 assert_eq!(route.paths.len(), 1);
3062 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3063 let fees = route.paths[0].hops[0].fee_msat;
3064 assert_eq!(fees, 5_000);
3068 fn disable_channels_test() {
3069 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3070 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3071 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3072 let scorer = ln_test_utils::TestScorer::new();
3073 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3074 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3076 // // Disable channels 4 and 12 by flags=2
3077 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3078 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3079 short_channel_id: 4,
3081 flags: 2, // to disable
3082 cltv_expiry_delta: 0,
3083 htlc_minimum_msat: 0,
3084 htlc_maximum_msat: MAX_VALUE_MSAT,
3086 fee_proportional_millionths: 0,
3087 excess_data: Vec::new()
3089 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3090 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3091 short_channel_id: 12,
3093 flags: 2, // to disable
3094 cltv_expiry_delta: 0,
3095 htlc_minimum_msat: 0,
3096 htlc_maximum_msat: MAX_VALUE_MSAT,
3098 fee_proportional_millionths: 0,
3099 excess_data: Vec::new()
3102 // If all the channels require some features we don't understand, route should fail
3103 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3104 assert_eq!(err, "Failed to find a path to the given destination");
3105 } else { panic!(); }
3107 // If we specify a channel to node7, that overrides our local channel view and that gets used
3108 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3109 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3110 assert_eq!(route.paths[0].hops.len(), 2);
3112 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3113 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3114 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3115 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3116 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3117 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3119 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3120 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3121 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3122 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3123 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3124 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3128 fn disable_node_test() {
3129 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3130 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3131 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3132 let scorer = ln_test_utils::TestScorer::new();
3133 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3134 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3136 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3137 let mut unknown_features = NodeFeatures::empty();
3138 unknown_features.set_unknown_feature_required();
3139 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3140 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3141 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3143 // If all nodes require some features we don't understand, route should fail
3144 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3145 assert_eq!(err, "Failed to find a path to the given destination");
3146 } else { panic!(); }
3148 // If we specify a channel to node7, that overrides our local channel view and that gets used
3149 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3150 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3151 assert_eq!(route.paths[0].hops.len(), 2);
3153 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3154 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3155 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3156 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3157 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3158 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3160 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3161 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3162 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3163 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3164 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3165 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3167 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3168 // naively) assume that the user checked the feature bits on the invoice, which override
3169 // the node_announcement.
3173 fn our_chans_test() {
3174 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3175 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3176 let scorer = ln_test_utils::TestScorer::new();
3177 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3178 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3180 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3181 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3182 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3183 assert_eq!(route.paths[0].hops.len(), 3);
3185 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3186 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3187 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3188 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3189 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3190 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3192 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3193 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3194 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3195 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3196 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3197 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3199 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3200 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3201 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3202 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3203 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3204 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3206 // If we specify a channel to node7, that overrides our local channel view and that gets used
3207 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3208 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3209 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3210 assert_eq!(route.paths[0].hops.len(), 2);
3212 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3213 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3214 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3215 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3216 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3217 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3219 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3220 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3221 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3222 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3223 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3224 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3227 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3228 let zero_fees = RoutingFees {
3230 proportional_millionths: 0,
3232 vec![RouteHint(vec![RouteHintHop {
3233 src_node_id: nodes[3],
3234 short_channel_id: 8,
3236 cltv_expiry_delta: (8 << 4) | 1,
3237 htlc_minimum_msat: None,
3238 htlc_maximum_msat: None,
3240 ]), RouteHint(vec![RouteHintHop {
3241 src_node_id: nodes[4],
3242 short_channel_id: 9,
3245 proportional_millionths: 0,
3247 cltv_expiry_delta: (9 << 4) | 1,
3248 htlc_minimum_msat: None,
3249 htlc_maximum_msat: None,
3250 }]), RouteHint(vec![RouteHintHop {
3251 src_node_id: nodes[5],
3252 short_channel_id: 10,
3254 cltv_expiry_delta: (10 << 4) | 1,
3255 htlc_minimum_msat: None,
3256 htlc_maximum_msat: None,
3260 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3261 let zero_fees = RoutingFees {
3263 proportional_millionths: 0,
3265 vec![RouteHint(vec![RouteHintHop {
3266 src_node_id: nodes[2],
3267 short_channel_id: 5,
3270 proportional_millionths: 0,
3272 cltv_expiry_delta: (5 << 4) | 1,
3273 htlc_minimum_msat: None,
3274 htlc_maximum_msat: None,
3276 src_node_id: nodes[3],
3277 short_channel_id: 8,
3279 cltv_expiry_delta: (8 << 4) | 1,
3280 htlc_minimum_msat: None,
3281 htlc_maximum_msat: None,
3283 ]), RouteHint(vec![RouteHintHop {
3284 src_node_id: nodes[4],
3285 short_channel_id: 9,
3288 proportional_millionths: 0,
3290 cltv_expiry_delta: (9 << 4) | 1,
3291 htlc_minimum_msat: None,
3292 htlc_maximum_msat: None,
3293 }]), RouteHint(vec![RouteHintHop {
3294 src_node_id: nodes[5],
3295 short_channel_id: 10,
3297 cltv_expiry_delta: (10 << 4) | 1,
3298 htlc_minimum_msat: None,
3299 htlc_maximum_msat: None,
3304 fn partial_route_hint_test() {
3305 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3306 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3307 let scorer = ln_test_utils::TestScorer::new();
3308 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3309 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3311 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3312 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3313 // RouteHint may be partially used by the algo to build the best path.
3315 // First check that last hop can't have its source as the payee.
3316 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3317 src_node_id: nodes[6],
3318 short_channel_id: 8,
3321 proportional_millionths: 0,
3323 cltv_expiry_delta: (8 << 4) | 1,
3324 htlc_minimum_msat: None,
3325 htlc_maximum_msat: None,
3328 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3329 invalid_last_hops.push(invalid_last_hop);
3331 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(invalid_last_hops).unwrap();
3332 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3333 assert_eq!(err, "Route hint cannot have the payee as the source.");
3334 } else { panic!(); }
3337 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3338 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3339 assert_eq!(route.paths[0].hops.len(), 5);
3341 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3342 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3343 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3344 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3345 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3346 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3348 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3349 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3350 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3351 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3352 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3353 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3355 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3356 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3357 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3358 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3359 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3360 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3362 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3363 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3364 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3365 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3366 // If we have a peer in the node map, we'll use their features here since we don't have
3367 // a way of figuring out their features from the invoice:
3368 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3369 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3371 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3372 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3373 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3374 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3375 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3376 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3379 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3380 let zero_fees = RoutingFees {
3382 proportional_millionths: 0,
3384 vec![RouteHint(vec![RouteHintHop {
3385 src_node_id: nodes[3],
3386 short_channel_id: 8,
3388 cltv_expiry_delta: (8 << 4) | 1,
3389 htlc_minimum_msat: None,
3390 htlc_maximum_msat: None,
3391 }]), RouteHint(vec![
3393 ]), RouteHint(vec![RouteHintHop {
3394 src_node_id: nodes[5],
3395 short_channel_id: 10,
3397 cltv_expiry_delta: (10 << 4) | 1,
3398 htlc_minimum_msat: None,
3399 htlc_maximum_msat: None,
3404 fn ignores_empty_last_hops_test() {
3405 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3406 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3407 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3408 let scorer = ln_test_utils::TestScorer::new();
3409 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3410 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3412 // Test handling of an empty RouteHint passed in Invoice.
3414 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3415 assert_eq!(route.paths[0].hops.len(), 5);
3417 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3418 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3419 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3420 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3421 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3422 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3424 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3425 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3426 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3427 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3428 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3429 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3431 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3432 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3433 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3434 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3435 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3436 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3438 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3439 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3440 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3441 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3442 // If we have a peer in the node map, we'll use their features here since we don't have
3443 // a way of figuring out their features from the invoice:
3444 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3445 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3447 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3448 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3449 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3450 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3451 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3452 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3455 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3457 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3458 let zero_fees = RoutingFees {
3460 proportional_millionths: 0,
3462 vec![RouteHint(vec![RouteHintHop {
3463 src_node_id: hint_hops[0],
3464 short_channel_id: 0xff00,
3467 proportional_millionths: 0,
3469 cltv_expiry_delta: (5 << 4) | 1,
3470 htlc_minimum_msat: None,
3471 htlc_maximum_msat: None,
3473 src_node_id: hint_hops[1],
3474 short_channel_id: 0xff01,
3476 cltv_expiry_delta: (8 << 4) | 1,
3477 htlc_minimum_msat: None,
3478 htlc_maximum_msat: None,
3483 fn multi_hint_last_hops_test() {
3484 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3485 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3486 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3487 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3488 let scorer = ln_test_utils::TestScorer::new();
3489 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3490 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3491 // Test through channels 2, 3, 0xff00, 0xff01.
3492 // Test shows that multiple hop hints are considered.
3494 // Disabling channels 6 & 7 by flags=2
3495 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3496 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3497 short_channel_id: 6,
3499 flags: 2, // to disable
3500 cltv_expiry_delta: 0,
3501 htlc_minimum_msat: 0,
3502 htlc_maximum_msat: MAX_VALUE_MSAT,
3504 fee_proportional_millionths: 0,
3505 excess_data: Vec::new()
3507 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3508 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3509 short_channel_id: 7,
3511 flags: 2, // to disable
3512 cltv_expiry_delta: 0,
3513 htlc_minimum_msat: 0,
3514 htlc_maximum_msat: MAX_VALUE_MSAT,
3516 fee_proportional_millionths: 0,
3517 excess_data: Vec::new()
3520 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3521 assert_eq!(route.paths[0].hops.len(), 4);
3523 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3524 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3525 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3526 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3527 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3528 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3530 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3531 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3532 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3533 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3534 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3535 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3537 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3538 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3539 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3540 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3541 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3542 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3544 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3545 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3546 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3547 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3548 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3549 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3553 fn private_multi_hint_last_hops_test() {
3554 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3555 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3557 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3558 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3560 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3561 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3562 let scorer = ln_test_utils::TestScorer::new();
3563 // Test through channels 2, 3, 0xff00, 0xff01.
3564 // Test shows that multiple hop hints are considered.
3566 // Disabling channels 6 & 7 by flags=2
3567 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3568 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3569 short_channel_id: 6,
3571 flags: 2, // to disable
3572 cltv_expiry_delta: 0,
3573 htlc_minimum_msat: 0,
3574 htlc_maximum_msat: MAX_VALUE_MSAT,
3576 fee_proportional_millionths: 0,
3577 excess_data: Vec::new()
3579 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3580 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3581 short_channel_id: 7,
3583 flags: 2, // to disable
3584 cltv_expiry_delta: 0,
3585 htlc_minimum_msat: 0,
3586 htlc_maximum_msat: MAX_VALUE_MSAT,
3588 fee_proportional_millionths: 0,
3589 excess_data: Vec::new()
3592 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &[42u8; 32]).unwrap();
3593 assert_eq!(route.paths[0].hops.len(), 4);
3595 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3596 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3597 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3598 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3599 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3600 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3602 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3603 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3604 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3605 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3606 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3607 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3609 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3610 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3611 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3612 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3613 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3614 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3616 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3617 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3618 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3619 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3620 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3621 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3624 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3625 let zero_fees = RoutingFees {
3627 proportional_millionths: 0,
3629 vec![RouteHint(vec![RouteHintHop {
3630 src_node_id: nodes[4],
3631 short_channel_id: 11,
3633 cltv_expiry_delta: (11 << 4) | 1,
3634 htlc_minimum_msat: None,
3635 htlc_maximum_msat: None,
3637 src_node_id: nodes[3],
3638 short_channel_id: 8,
3640 cltv_expiry_delta: (8 << 4) | 1,
3641 htlc_minimum_msat: None,
3642 htlc_maximum_msat: None,
3643 }]), RouteHint(vec![RouteHintHop {
3644 src_node_id: nodes[4],
3645 short_channel_id: 9,
3648 proportional_millionths: 0,
3650 cltv_expiry_delta: (9 << 4) | 1,
3651 htlc_minimum_msat: None,
3652 htlc_maximum_msat: None,
3653 }]), RouteHint(vec![RouteHintHop {
3654 src_node_id: nodes[5],
3655 short_channel_id: 10,
3657 cltv_expiry_delta: (10 << 4) | 1,
3658 htlc_minimum_msat: None,
3659 htlc_maximum_msat: None,
3664 fn last_hops_with_public_channel_test() {
3665 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3666 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3667 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3668 let scorer = ln_test_utils::TestScorer::new();
3669 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3670 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3671 // This test shows that public routes can be present in the invoice
3672 // which would be handled in the same manner.
3674 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3675 assert_eq!(route.paths[0].hops.len(), 5);
3677 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3678 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3679 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3680 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3681 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3682 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3684 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3685 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3686 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3687 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3688 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3689 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3691 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3692 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3693 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3694 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3695 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3696 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3698 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3699 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3700 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3701 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3702 // If we have a peer in the node map, we'll use their features here since we don't have
3703 // a way of figuring out their features from the invoice:
3704 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3705 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3707 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3708 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3709 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3710 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3711 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3712 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3716 fn our_chans_last_hop_connect_test() {
3717 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3718 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3719 let scorer = ln_test_utils::TestScorer::new();
3720 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3721 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3723 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3724 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3725 let mut last_hops = last_hops(&nodes);
3726 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3727 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3728 assert_eq!(route.paths[0].hops.len(), 2);
3730 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3731 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3732 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3733 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3734 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3735 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3737 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3738 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3739 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3740 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3741 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3742 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3744 last_hops[0].0[0].fees.base_msat = 1000;
3746 // Revert to via 6 as the fee on 8 goes up
3747 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops).unwrap();
3748 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3749 assert_eq!(route.paths[0].hops.len(), 4);
3751 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3752 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3753 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3754 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3755 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3756 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3758 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3759 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3760 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3761 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3762 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3763 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3765 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3766 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3767 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3768 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3769 // If we have a peer in the node map, we'll use their features here since we don't have
3770 // a way of figuring out their features from the invoice:
3771 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3772 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3774 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3775 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3776 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3777 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3778 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3779 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3781 // ...but still use 8 for larger payments as 6 has a variable feerate
3782 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
3783 assert_eq!(route.paths[0].hops.len(), 5);
3785 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3786 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3787 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3788 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3789 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3790 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3792 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3793 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3794 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3795 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3796 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3797 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3799 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3800 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3801 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3802 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3803 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3804 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3806 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3807 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3808 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
3809 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3810 // If we have a peer in the node map, we'll use their features here since we don't have
3811 // a way of figuring out their features from the invoice:
3812 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3813 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3815 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3816 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3817 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
3818 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3819 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3820 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3823 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> {
3824 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3825 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3826 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3828 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3829 let last_hops = RouteHint(vec![RouteHintHop {
3830 src_node_id: middle_node_id,
3831 short_channel_id: 8,
3834 proportional_millionths: last_hop_fee_prop,
3836 cltv_expiry_delta: (8 << 4) | 1,
3837 htlc_minimum_msat: None,
3838 htlc_maximum_msat: last_hop_htlc_max,
3840 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
3841 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3842 let scorer = ln_test_utils::TestScorer::new();
3843 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3844 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3845 let logger = ln_test_utils::TestLogger::new();
3846 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
3847 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3848 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, &logger, &scorer, &(), &random_seed_bytes);
3853 fn unannounced_path_test() {
3854 // We should be able to send a payment to a destination without any help of a routing graph
3855 // if we have a channel with a common counterparty that appears in the first and last hop
3857 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3859 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3860 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3861 assert_eq!(route.paths[0].hops.len(), 2);
3863 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
3864 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3865 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
3866 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3867 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
3868 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3870 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
3871 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3872 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
3873 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3874 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3875 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3879 fn overflow_unannounced_path_test_liquidity_underflow() {
3880 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3881 // the last-hop had a fee which overflowed a u64, we'd panic.
3882 // This was due to us adding the first-hop from us unconditionally, causing us to think
3883 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3884 // In this test, we previously hit a subtraction underflow due to having less available
3885 // liquidity at the last hop than 0.
3886 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());
3890 fn overflow_unannounced_path_test_feerate_overflow() {
3891 // This tests for the same case as above, except instead of hitting a subtraction
3892 // underflow, we hit a case where the fee charged at a hop overflowed.
3893 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());
3897 fn available_amount_while_routing_test() {
3898 // Tests whether we choose the correct available channel amount while routing.
3900 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3901 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3902 let scorer = ln_test_utils::TestScorer::new();
3903 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3904 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3905 let config = UserConfig::default();
3906 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3908 // We will use a simple single-path route from
3909 // our node to node2 via node0: channels {1, 3}.
3911 // First disable all other paths.
3912 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3913 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3914 short_channel_id: 2,
3917 cltv_expiry_delta: 0,
3918 htlc_minimum_msat: 0,
3919 htlc_maximum_msat: 100_000,
3921 fee_proportional_millionths: 0,
3922 excess_data: Vec::new()
3924 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3925 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3926 short_channel_id: 12,
3929 cltv_expiry_delta: 0,
3930 htlc_minimum_msat: 0,
3931 htlc_maximum_msat: 100_000,
3933 fee_proportional_millionths: 0,
3934 excess_data: Vec::new()
3937 // Make the first channel (#1) very permissive,
3938 // and we will be testing all limits on the second channel.
3939 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3940 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3941 short_channel_id: 1,
3944 cltv_expiry_delta: 0,
3945 htlc_minimum_msat: 0,
3946 htlc_maximum_msat: 1_000_000_000,
3948 fee_proportional_millionths: 0,
3949 excess_data: Vec::new()
3952 // First, let's see if routing works if we have absolutely no idea about the available amount.
3953 // In this case, it should be set to 250_000 sats.
3954 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3955 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3956 short_channel_id: 3,
3959 cltv_expiry_delta: 0,
3960 htlc_minimum_msat: 0,
3961 htlc_maximum_msat: 250_000_000,
3963 fee_proportional_millionths: 0,
3964 excess_data: Vec::new()
3968 // Attempt to route more than available results in a failure.
3969 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3970 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
3971 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3972 } else { panic!(); }
3976 // Now, attempt to route an exact amount we have should be fine.
3977 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000_000, Arc::clone(&logger), &scorer, &(),&random_seed_bytes).unwrap();
3978 assert_eq!(route.paths.len(), 1);
3979 let path = route.paths.last().unwrap();
3980 assert_eq!(path.hops.len(), 2);
3981 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
3982 assert_eq!(path.final_value_msat(), 250_000_000);
3985 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3986 // Disable channel #1 and use another first hop.
3987 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3988 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3989 short_channel_id: 1,
3992 cltv_expiry_delta: 0,
3993 htlc_minimum_msat: 0,
3994 htlc_maximum_msat: 1_000_000_000,
3996 fee_proportional_millionths: 0,
3997 excess_data: Vec::new()
4000 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4001 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4004 // Attempt to route more than available results in a failure.
4005 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4006 &our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4007 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4008 } else { panic!(); }
4012 // Now, attempt to route an exact amount we have should be fine.
4013 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4014 assert_eq!(route.paths.len(), 1);
4015 let path = route.paths.last().unwrap();
4016 assert_eq!(path.hops.len(), 2);
4017 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4018 assert_eq!(path.final_value_msat(), 200_000_000);
4021 // Enable channel #1 back.
4022 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4023 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4024 short_channel_id: 1,
4027 cltv_expiry_delta: 0,
4028 htlc_minimum_msat: 0,
4029 htlc_maximum_msat: 1_000_000_000,
4031 fee_proportional_millionths: 0,
4032 excess_data: Vec::new()
4036 // Now let's see if routing works if we know only htlc_maximum_msat.
4037 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4038 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4039 short_channel_id: 3,
4042 cltv_expiry_delta: 0,
4043 htlc_minimum_msat: 0,
4044 htlc_maximum_msat: 15_000,
4046 fee_proportional_millionths: 0,
4047 excess_data: Vec::new()
4051 // Attempt to route more than available results in a failure.
4052 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4053 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4054 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4055 } else { panic!(); }
4059 // Now, attempt to route an exact amount we have should be fine.
4060 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4061 assert_eq!(route.paths.len(), 1);
4062 let path = route.paths.last().unwrap();
4063 assert_eq!(path.hops.len(), 2);
4064 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4065 assert_eq!(path.final_value_msat(), 15_000);
4068 // Now let's see if routing works if we know only capacity from the UTXO.
4070 // We can't change UTXO capacity on the fly, so we'll disable
4071 // the existing channel and add another one with the capacity we need.
4072 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4073 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4074 short_channel_id: 3,
4077 cltv_expiry_delta: 0,
4078 htlc_minimum_msat: 0,
4079 htlc_maximum_msat: MAX_VALUE_MSAT,
4081 fee_proportional_millionths: 0,
4082 excess_data: Vec::new()
4085 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4086 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4087 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4088 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4089 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4091 *chain_monitor.utxo_ret.lock().unwrap() =
4092 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4093 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4095 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4096 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4097 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4098 short_channel_id: 333,
4101 cltv_expiry_delta: (3 << 4) | 1,
4102 htlc_minimum_msat: 0,
4103 htlc_maximum_msat: 15_000,
4105 fee_proportional_millionths: 0,
4106 excess_data: Vec::new()
4108 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4109 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4110 short_channel_id: 333,
4113 cltv_expiry_delta: (3 << 4) | 2,
4114 htlc_minimum_msat: 0,
4115 htlc_maximum_msat: 15_000,
4117 fee_proportional_millionths: 0,
4118 excess_data: Vec::new()
4122 // Attempt to route more than available results in a failure.
4123 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4124 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4125 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4126 } else { panic!(); }
4130 // Now, attempt to route an exact amount we have should be fine.
4131 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4132 assert_eq!(route.paths.len(), 1);
4133 let path = route.paths.last().unwrap();
4134 assert_eq!(path.hops.len(), 2);
4135 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4136 assert_eq!(path.final_value_msat(), 15_000);
4139 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4140 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4141 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4142 short_channel_id: 333,
4145 cltv_expiry_delta: 0,
4146 htlc_minimum_msat: 0,
4147 htlc_maximum_msat: 10_000,
4149 fee_proportional_millionths: 0,
4150 excess_data: Vec::new()
4154 // Attempt to route more than available results in a failure.
4155 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4156 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4157 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4158 } else { panic!(); }
4162 // Now, attempt to route an exact amount we have should be fine.
4163 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4164 assert_eq!(route.paths.len(), 1);
4165 let path = route.paths.last().unwrap();
4166 assert_eq!(path.hops.len(), 2);
4167 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4168 assert_eq!(path.final_value_msat(), 10_000);
4173 fn available_liquidity_last_hop_test() {
4174 // Check that available liquidity properly limits the path even when only
4175 // one of the latter hops is limited.
4176 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4177 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4178 let scorer = ln_test_utils::TestScorer::new();
4179 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4180 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4181 let config = UserConfig::default();
4182 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4184 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4185 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4186 // Total capacity: 50 sats.
4188 // Disable other potential paths.
4189 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4190 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4191 short_channel_id: 2,
4194 cltv_expiry_delta: 0,
4195 htlc_minimum_msat: 0,
4196 htlc_maximum_msat: 100_000,
4198 fee_proportional_millionths: 0,
4199 excess_data: Vec::new()
4201 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4202 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4203 short_channel_id: 7,
4206 cltv_expiry_delta: 0,
4207 htlc_minimum_msat: 0,
4208 htlc_maximum_msat: 100_000,
4210 fee_proportional_millionths: 0,
4211 excess_data: Vec::new()
4216 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4217 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4218 short_channel_id: 12,
4221 cltv_expiry_delta: 0,
4222 htlc_minimum_msat: 0,
4223 htlc_maximum_msat: 100_000,
4225 fee_proportional_millionths: 0,
4226 excess_data: Vec::new()
4228 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4229 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4230 short_channel_id: 13,
4233 cltv_expiry_delta: 0,
4234 htlc_minimum_msat: 0,
4235 htlc_maximum_msat: 100_000,
4237 fee_proportional_millionths: 0,
4238 excess_data: Vec::new()
4241 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4242 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4243 short_channel_id: 6,
4246 cltv_expiry_delta: 0,
4247 htlc_minimum_msat: 0,
4248 htlc_maximum_msat: 50_000,
4250 fee_proportional_millionths: 0,
4251 excess_data: Vec::new()
4253 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4254 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4255 short_channel_id: 11,
4258 cltv_expiry_delta: 0,
4259 htlc_minimum_msat: 0,
4260 htlc_maximum_msat: 100_000,
4262 fee_proportional_millionths: 0,
4263 excess_data: Vec::new()
4266 // Attempt to route more than available results in a failure.
4267 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4268 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4269 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4270 } else { panic!(); }
4274 // Now, attempt to route 49 sats (just a bit below the capacity).
4275 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4276 assert_eq!(route.paths.len(), 1);
4277 let mut total_amount_paid_msat = 0;
4278 for path in &route.paths {
4279 assert_eq!(path.hops.len(), 4);
4280 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4281 total_amount_paid_msat += path.final_value_msat();
4283 assert_eq!(total_amount_paid_msat, 49_000);
4287 // Attempt to route an exact amount is also fine
4288 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4289 assert_eq!(route.paths.len(), 1);
4290 let mut total_amount_paid_msat = 0;
4291 for path in &route.paths {
4292 assert_eq!(path.hops.len(), 4);
4293 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4294 total_amount_paid_msat += path.final_value_msat();
4296 assert_eq!(total_amount_paid_msat, 50_000);
4301 fn ignore_fee_first_hop_test() {
4302 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4303 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4304 let scorer = ln_test_utils::TestScorer::new();
4305 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4306 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4307 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4309 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4310 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4311 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4312 short_channel_id: 1,
4315 cltv_expiry_delta: 0,
4316 htlc_minimum_msat: 0,
4317 htlc_maximum_msat: 100_000,
4318 fee_base_msat: 1_000_000,
4319 fee_proportional_millionths: 0,
4320 excess_data: Vec::new()
4322 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4323 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4324 short_channel_id: 3,
4327 cltv_expiry_delta: 0,
4328 htlc_minimum_msat: 0,
4329 htlc_maximum_msat: 50_000,
4331 fee_proportional_millionths: 0,
4332 excess_data: Vec::new()
4336 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4337 assert_eq!(route.paths.len(), 1);
4338 let mut total_amount_paid_msat = 0;
4339 for path in &route.paths {
4340 assert_eq!(path.hops.len(), 2);
4341 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4342 total_amount_paid_msat += path.final_value_msat();
4344 assert_eq!(total_amount_paid_msat, 50_000);
4349 fn simple_mpp_route_test() {
4350 let (secp_ctx, _, _, _, _) = build_graph();
4351 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4352 let config = UserConfig::default();
4353 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4354 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4355 do_simple_mpp_route_test(clear_payment_params);
4357 // MPP to a 1-hop blinded path for nodes[2]
4358 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4359 let blinded_path = BlindedPath {
4360 introduction_node_id: nodes[2],
4361 blinding_point: ln_test_utils::pubkey(42),
4362 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4364 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4366 fee_proportional_millionths: 0,
4367 htlc_minimum_msat: 0,
4368 htlc_maximum_msat: 0,
4369 cltv_expiry_delta: 0,
4370 features: BlindedHopFeatures::empty(),
4372 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4373 .with_bolt12_features(bolt12_features.clone()).unwrap();
4374 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4376 // MPP to 3 2-hop blinded paths
4377 let mut blinded_path_node_0 = blinded_path.clone();
4378 blinded_path_node_0.introduction_node_id = nodes[0];
4379 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4380 let mut node_0_payinfo = blinded_payinfo.clone();
4381 node_0_payinfo.htlc_maximum_msat = 50_000;
4383 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4384 blinded_path_node_7.introduction_node_id = nodes[7];
4385 let mut node_7_payinfo = blinded_payinfo.clone();
4386 node_7_payinfo.htlc_maximum_msat = 60_000;
4388 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4389 blinded_path_node_1.introduction_node_id = nodes[1];
4390 let mut node_1_payinfo = blinded_payinfo.clone();
4391 node_1_payinfo.htlc_maximum_msat = 180_000;
4393 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4395 (node_0_payinfo, blinded_path_node_0),
4396 (node_7_payinfo, blinded_path_node_7),
4397 (node_1_payinfo, blinded_path_node_1)
4399 .with_bolt12_features(bolt12_features).unwrap();
4400 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4404 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4405 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4406 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4407 let scorer = ln_test_utils::TestScorer::new();
4408 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4409 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4411 // We need a route consisting of 3 paths:
4412 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4413 // To achieve this, the amount being transferred should be around
4414 // the total capacity of these 3 paths.
4416 // First, we set limits on these (previously unlimited) channels.
4417 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4419 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4420 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4421 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4422 short_channel_id: 1,
4425 cltv_expiry_delta: 0,
4426 htlc_minimum_msat: 0,
4427 htlc_maximum_msat: 100_000,
4429 fee_proportional_millionths: 0,
4430 excess_data: Vec::new()
4432 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4433 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4434 short_channel_id: 3,
4437 cltv_expiry_delta: 0,
4438 htlc_minimum_msat: 0,
4439 htlc_maximum_msat: 50_000,
4441 fee_proportional_millionths: 0,
4442 excess_data: Vec::new()
4445 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4446 // (total limit 60).
4447 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4448 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4449 short_channel_id: 12,
4452 cltv_expiry_delta: 0,
4453 htlc_minimum_msat: 0,
4454 htlc_maximum_msat: 60_000,
4456 fee_proportional_millionths: 0,
4457 excess_data: Vec::new()
4459 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4460 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4461 short_channel_id: 13,
4464 cltv_expiry_delta: 0,
4465 htlc_minimum_msat: 0,
4466 htlc_maximum_msat: 60_000,
4468 fee_proportional_millionths: 0,
4469 excess_data: Vec::new()
4472 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4473 // (total capacity 180 sats).
4474 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4475 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4476 short_channel_id: 2,
4479 cltv_expiry_delta: 0,
4480 htlc_minimum_msat: 0,
4481 htlc_maximum_msat: 200_000,
4483 fee_proportional_millionths: 0,
4484 excess_data: Vec::new()
4486 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4487 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4488 short_channel_id: 4,
4491 cltv_expiry_delta: 0,
4492 htlc_minimum_msat: 0,
4493 htlc_maximum_msat: 180_000,
4495 fee_proportional_millionths: 0,
4496 excess_data: Vec::new()
4500 // Attempt to route more than available results in a failure.
4501 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4502 &our_id, &payment_params, &network_graph.read_only(), None, 300_000,
4503 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4504 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4505 } else { panic!(); }
4509 // Attempt to route while setting max_path_count to 0 results in a failure.
4510 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4511 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4512 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100,
4513 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4514 assert_eq!(err, "Can't find a route with no paths allowed.");
4515 } else { panic!(); }
4519 // Attempt to route while setting max_path_count to 3 results in a failure.
4520 // This is the case because the minimal_value_contribution_msat would require each path
4521 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4522 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4523 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4524 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000,
4525 Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4526 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4527 } else { panic!(); }
4531 // Now, attempt to route 250 sats (just a bit below the capacity).
4532 // Our algorithm should provide us with these 3 paths.
4533 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4534 250_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4535 assert_eq!(route.paths.len(), 3);
4536 let mut total_amount_paid_msat = 0;
4537 for path in &route.paths {
4538 if let Some(bt) = &path.blinded_tail {
4539 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4541 assert_eq!(path.hops.len(), 2);
4542 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4544 total_amount_paid_msat += path.final_value_msat();
4546 assert_eq!(total_amount_paid_msat, 250_000);
4550 // Attempt to route an exact amount is also fine
4551 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4552 290_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4553 assert_eq!(route.paths.len(), 3);
4554 let mut total_amount_paid_msat = 0;
4555 for path in &route.paths {
4556 if payment_params.payee.blinded_route_hints().len() != 0 {
4557 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4558 if let Some(bt) = &path.blinded_tail {
4559 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4560 if bt.hops.len() > 1 {
4561 assert_eq!(path.hops.last().unwrap().pubkey,
4562 payment_params.payee.blinded_route_hints().iter()
4563 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4564 .map(|(_, p)| p.introduction_node_id).unwrap());
4566 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4569 assert_eq!(path.hops.len(), 2);
4570 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4572 total_amount_paid_msat += path.final_value_msat();
4574 assert_eq!(total_amount_paid_msat, 290_000);
4579 fn long_mpp_route_test() {
4580 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4581 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4582 let scorer = ln_test_utils::TestScorer::new();
4583 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4584 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4585 let config = UserConfig::default();
4586 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4588 // We need a route consisting of 3 paths:
4589 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4590 // Note that these paths overlap (channels 5, 12, 13).
4591 // We will route 300 sats.
4592 // Each path will have 100 sats capacity, those channels which
4593 // are used twice will have 200 sats capacity.
4595 // Disable other potential paths.
4596 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4598 short_channel_id: 2,
4601 cltv_expiry_delta: 0,
4602 htlc_minimum_msat: 0,
4603 htlc_maximum_msat: 100_000,
4605 fee_proportional_millionths: 0,
4606 excess_data: Vec::new()
4608 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4609 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4610 short_channel_id: 7,
4613 cltv_expiry_delta: 0,
4614 htlc_minimum_msat: 0,
4615 htlc_maximum_msat: 100_000,
4617 fee_proportional_millionths: 0,
4618 excess_data: Vec::new()
4621 // Path via {node0, node2} is channels {1, 3, 5}.
4622 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4624 short_channel_id: 1,
4627 cltv_expiry_delta: 0,
4628 htlc_minimum_msat: 0,
4629 htlc_maximum_msat: 100_000,
4631 fee_proportional_millionths: 0,
4632 excess_data: Vec::new()
4634 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4635 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4636 short_channel_id: 3,
4639 cltv_expiry_delta: 0,
4640 htlc_minimum_msat: 0,
4641 htlc_maximum_msat: 100_000,
4643 fee_proportional_millionths: 0,
4644 excess_data: Vec::new()
4647 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4648 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4649 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4650 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4651 short_channel_id: 5,
4654 cltv_expiry_delta: 0,
4655 htlc_minimum_msat: 0,
4656 htlc_maximum_msat: 200_000,
4658 fee_proportional_millionths: 0,
4659 excess_data: Vec::new()
4662 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4663 // Add 100 sats to the capacities of {12, 13}, because these channels
4664 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4665 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4666 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4667 short_channel_id: 12,
4670 cltv_expiry_delta: 0,
4671 htlc_minimum_msat: 0,
4672 htlc_maximum_msat: 200_000,
4674 fee_proportional_millionths: 0,
4675 excess_data: Vec::new()
4677 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4678 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4679 short_channel_id: 13,
4682 cltv_expiry_delta: 0,
4683 htlc_minimum_msat: 0,
4684 htlc_maximum_msat: 200_000,
4686 fee_proportional_millionths: 0,
4687 excess_data: Vec::new()
4690 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4691 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4692 short_channel_id: 6,
4695 cltv_expiry_delta: 0,
4696 htlc_minimum_msat: 0,
4697 htlc_maximum_msat: 100_000,
4699 fee_proportional_millionths: 0,
4700 excess_data: Vec::new()
4702 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4703 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4704 short_channel_id: 11,
4707 cltv_expiry_delta: 0,
4708 htlc_minimum_msat: 0,
4709 htlc_maximum_msat: 100_000,
4711 fee_proportional_millionths: 0,
4712 excess_data: Vec::new()
4715 // Path via {node7, node2} is channels {12, 13, 5}.
4716 // We already limited them to 200 sats (they are used twice for 100 sats).
4717 // Nothing to do here.
4720 // Attempt to route more than available results in a failure.
4721 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4722 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
4723 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4724 } else { panic!(); }
4728 // Now, attempt to route 300 sats (exact amount we can route).
4729 // Our algorithm should provide us with these 3 paths, 100 sats each.
4730 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4731 assert_eq!(route.paths.len(), 3);
4733 let mut total_amount_paid_msat = 0;
4734 for path in &route.paths {
4735 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4736 total_amount_paid_msat += path.final_value_msat();
4738 assert_eq!(total_amount_paid_msat, 300_000);
4744 fn mpp_cheaper_route_test() {
4745 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4746 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4747 let scorer = ln_test_utils::TestScorer::new();
4748 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4749 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4750 let config = UserConfig::default();
4751 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4753 // This test checks that if we have two cheaper paths and one more expensive path,
4754 // so that liquidity-wise any 2 of 3 combination is sufficient,
4755 // two cheaper paths will be taken.
4756 // These paths have equal available liquidity.
4758 // We need a combination of 3 paths:
4759 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4760 // Note that these paths overlap (channels 5, 12, 13).
4761 // Each path will have 100 sats capacity, those channels which
4762 // are used twice will have 200 sats capacity.
4764 // Disable other potential paths.
4765 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4766 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4767 short_channel_id: 2,
4770 cltv_expiry_delta: 0,
4771 htlc_minimum_msat: 0,
4772 htlc_maximum_msat: 100_000,
4774 fee_proportional_millionths: 0,
4775 excess_data: Vec::new()
4777 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4778 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4779 short_channel_id: 7,
4782 cltv_expiry_delta: 0,
4783 htlc_minimum_msat: 0,
4784 htlc_maximum_msat: 100_000,
4786 fee_proportional_millionths: 0,
4787 excess_data: Vec::new()
4790 // Path via {node0, node2} is channels {1, 3, 5}.
4791 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4792 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4793 short_channel_id: 1,
4796 cltv_expiry_delta: 0,
4797 htlc_minimum_msat: 0,
4798 htlc_maximum_msat: 100_000,
4800 fee_proportional_millionths: 0,
4801 excess_data: Vec::new()
4803 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4804 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4805 short_channel_id: 3,
4808 cltv_expiry_delta: 0,
4809 htlc_minimum_msat: 0,
4810 htlc_maximum_msat: 100_000,
4812 fee_proportional_millionths: 0,
4813 excess_data: Vec::new()
4816 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4817 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4818 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4819 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4820 short_channel_id: 5,
4823 cltv_expiry_delta: 0,
4824 htlc_minimum_msat: 0,
4825 htlc_maximum_msat: 200_000,
4827 fee_proportional_millionths: 0,
4828 excess_data: Vec::new()
4831 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4832 // Add 100 sats to the capacities of {12, 13}, because these channels
4833 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4834 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4836 short_channel_id: 12,
4839 cltv_expiry_delta: 0,
4840 htlc_minimum_msat: 0,
4841 htlc_maximum_msat: 200_000,
4843 fee_proportional_millionths: 0,
4844 excess_data: Vec::new()
4846 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4848 short_channel_id: 13,
4851 cltv_expiry_delta: 0,
4852 htlc_minimum_msat: 0,
4853 htlc_maximum_msat: 200_000,
4855 fee_proportional_millionths: 0,
4856 excess_data: Vec::new()
4859 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4860 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4861 short_channel_id: 6,
4864 cltv_expiry_delta: 0,
4865 htlc_minimum_msat: 0,
4866 htlc_maximum_msat: 100_000,
4867 fee_base_msat: 1_000,
4868 fee_proportional_millionths: 0,
4869 excess_data: Vec::new()
4871 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4872 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4873 short_channel_id: 11,
4876 cltv_expiry_delta: 0,
4877 htlc_minimum_msat: 0,
4878 htlc_maximum_msat: 100_000,
4880 fee_proportional_millionths: 0,
4881 excess_data: Vec::new()
4884 // Path via {node7, node2} is channels {12, 13, 5}.
4885 // We already limited them to 200 sats (they are used twice for 100 sats).
4886 // Nothing to do here.
4889 // Now, attempt to route 180 sats.
4890 // Our algorithm should provide us with these 2 paths.
4891 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
4892 assert_eq!(route.paths.len(), 2);
4894 let mut total_value_transferred_msat = 0;
4895 let mut total_paid_msat = 0;
4896 for path in &route.paths {
4897 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4898 total_value_transferred_msat += path.final_value_msat();
4899 for hop in &path.hops {
4900 total_paid_msat += hop.fee_msat;
4903 // If we paid fee, this would be higher.
4904 assert_eq!(total_value_transferred_msat, 180_000);
4905 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4906 assert_eq!(total_fees_paid, 0);
4911 fn fees_on_mpp_route_test() {
4912 // This test makes sure that MPP algorithm properly takes into account
4913 // fees charged on the channels, by making the fees impactful:
4914 // if the fee is not properly accounted for, the behavior is different.
4915 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4916 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4917 let scorer = ln_test_utils::TestScorer::new();
4918 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4919 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4920 let config = UserConfig::default();
4921 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4923 // We need a route consisting of 2 paths:
4924 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4925 // We will route 200 sats, Each path will have 100 sats capacity.
4927 // This test is not particularly stable: e.g.,
4928 // there's a way to route via {node0, node2, node4}.
4929 // It works while pathfinding is deterministic, but can be broken otherwise.
4930 // It's fine to ignore this concern for now.
4932 // Disable other potential paths.
4933 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4934 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4935 short_channel_id: 2,
4938 cltv_expiry_delta: 0,
4939 htlc_minimum_msat: 0,
4940 htlc_maximum_msat: 100_000,
4942 fee_proportional_millionths: 0,
4943 excess_data: Vec::new()
4946 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4947 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4948 short_channel_id: 7,
4951 cltv_expiry_delta: 0,
4952 htlc_minimum_msat: 0,
4953 htlc_maximum_msat: 100_000,
4955 fee_proportional_millionths: 0,
4956 excess_data: Vec::new()
4959 // Path via {node0, node2} is channels {1, 3, 5}.
4960 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4962 short_channel_id: 1,
4965 cltv_expiry_delta: 0,
4966 htlc_minimum_msat: 0,
4967 htlc_maximum_msat: 100_000,
4969 fee_proportional_millionths: 0,
4970 excess_data: Vec::new()
4972 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4974 short_channel_id: 3,
4977 cltv_expiry_delta: 0,
4978 htlc_minimum_msat: 0,
4979 htlc_maximum_msat: 100_000,
4981 fee_proportional_millionths: 0,
4982 excess_data: Vec::new()
4985 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4986 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4987 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4988 short_channel_id: 5,
4991 cltv_expiry_delta: 0,
4992 htlc_minimum_msat: 0,
4993 htlc_maximum_msat: 100_000,
4995 fee_proportional_millionths: 0,
4996 excess_data: Vec::new()
4999 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5000 // All channels should be 100 sats capacity. But for the fee experiment,
5001 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5002 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5003 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5004 // so no matter how large are other channels,
5005 // the whole path will be limited by 100 sats with just these 2 conditions:
5006 // - channel 12 capacity is 250 sats
5007 // - fee for channel 6 is 150 sats
5008 // Let's test this by enforcing these 2 conditions and removing other limits.
5009 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5010 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5011 short_channel_id: 12,
5014 cltv_expiry_delta: 0,
5015 htlc_minimum_msat: 0,
5016 htlc_maximum_msat: 250_000,
5018 fee_proportional_millionths: 0,
5019 excess_data: Vec::new()
5021 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5022 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5023 short_channel_id: 13,
5026 cltv_expiry_delta: 0,
5027 htlc_minimum_msat: 0,
5028 htlc_maximum_msat: MAX_VALUE_MSAT,
5030 fee_proportional_millionths: 0,
5031 excess_data: Vec::new()
5034 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5035 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5036 short_channel_id: 6,
5039 cltv_expiry_delta: 0,
5040 htlc_minimum_msat: 0,
5041 htlc_maximum_msat: MAX_VALUE_MSAT,
5042 fee_base_msat: 150_000,
5043 fee_proportional_millionths: 0,
5044 excess_data: Vec::new()
5046 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5047 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5048 short_channel_id: 11,
5051 cltv_expiry_delta: 0,
5052 htlc_minimum_msat: 0,
5053 htlc_maximum_msat: MAX_VALUE_MSAT,
5055 fee_proportional_millionths: 0,
5056 excess_data: Vec::new()
5060 // Attempt to route more than available results in a failure.
5061 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5062 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
5063 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5064 } else { panic!(); }
5068 // Now, attempt to route 200 sats (exact amount we can route).
5069 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5070 assert_eq!(route.paths.len(), 2);
5072 let mut total_amount_paid_msat = 0;
5073 for path in &route.paths {
5074 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5075 total_amount_paid_msat += path.final_value_msat();
5077 assert_eq!(total_amount_paid_msat, 200_000);
5078 assert_eq!(route.get_total_fees(), 150_000);
5083 fn mpp_with_last_hops() {
5084 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5085 // via a single last-hop route hint, we'd fail to route if we first collected routes
5086 // totaling close but not quite enough to fund the full payment.
5088 // This was because we considered last-hop hints to have exactly the sought payment amount
5089 // instead of the amount we were trying to collect, needlessly limiting our path searching
5090 // at the very first hop.
5092 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5093 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5094 // to only have the remaining to-collect amount in available liquidity.
5096 // This bug appeared in production in some specific channel configurations.
5097 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5098 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5099 let scorer = ln_test_utils::TestScorer::new();
5100 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5101 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5102 let config = UserConfig::default();
5103 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5104 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5105 src_node_id: nodes[2],
5106 short_channel_id: 42,
5107 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5108 cltv_expiry_delta: 42,
5109 htlc_minimum_msat: None,
5110 htlc_maximum_msat: None,
5111 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5113 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5114 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5115 // would first use the no-fee route and then fail to find a path along the second route as
5116 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5117 // under 5% of our payment amount.
5118 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5119 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5120 short_channel_id: 1,
5123 cltv_expiry_delta: (5 << 4) | 5,
5124 htlc_minimum_msat: 0,
5125 htlc_maximum_msat: 99_000,
5126 fee_base_msat: u32::max_value(),
5127 fee_proportional_millionths: u32::max_value(),
5128 excess_data: Vec::new()
5130 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5131 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5132 short_channel_id: 2,
5135 cltv_expiry_delta: (5 << 4) | 3,
5136 htlc_minimum_msat: 0,
5137 htlc_maximum_msat: 99_000,
5138 fee_base_msat: u32::max_value(),
5139 fee_proportional_millionths: u32::max_value(),
5140 excess_data: Vec::new()
5142 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5144 short_channel_id: 4,
5147 cltv_expiry_delta: (4 << 4) | 1,
5148 htlc_minimum_msat: 0,
5149 htlc_maximum_msat: MAX_VALUE_MSAT,
5151 fee_proportional_millionths: 0,
5152 excess_data: Vec::new()
5154 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5156 short_channel_id: 13,
5158 flags: 0|2, // Channel disabled
5159 cltv_expiry_delta: (13 << 4) | 1,
5160 htlc_minimum_msat: 0,
5161 htlc_maximum_msat: MAX_VALUE_MSAT,
5163 fee_proportional_millionths: 2000000,
5164 excess_data: Vec::new()
5167 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5169 let mut route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5170 assert_eq!(route.paths.len(), 2);
5171 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5172 // Paths are manually ordered ordered by SCID, so:
5173 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5174 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5175 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5176 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5177 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5178 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5179 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5180 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5181 assert_eq!(route.get_total_fees(), 1);
5182 assert_eq!(route.get_total_amount(), 100_000);
5186 fn drop_lowest_channel_mpp_route_test() {
5187 // This test checks that low-capacity channel is dropped when after
5188 // path finding we realize that we found more capacity than we need.
5189 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5190 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5191 let scorer = ln_test_utils::TestScorer::new();
5192 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5193 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5194 let config = UserConfig::default();
5195 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5196 .with_max_channel_saturation_power_of_half(0);
5198 // We need a route consisting of 3 paths:
5199 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5201 // The first and the second paths should be sufficient, but the third should be
5202 // cheaper, so that we select it but drop later.
5204 // First, we set limits on these (previously unlimited) channels.
5205 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5207 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5208 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5209 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5210 short_channel_id: 1,
5213 cltv_expiry_delta: 0,
5214 htlc_minimum_msat: 0,
5215 htlc_maximum_msat: 100_000,
5217 fee_proportional_millionths: 0,
5218 excess_data: Vec::new()
5220 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5221 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5222 short_channel_id: 3,
5225 cltv_expiry_delta: 0,
5226 htlc_minimum_msat: 0,
5227 htlc_maximum_msat: 50_000,
5229 fee_proportional_millionths: 0,
5230 excess_data: Vec::new()
5233 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5234 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5235 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5236 short_channel_id: 12,
5239 cltv_expiry_delta: 0,
5240 htlc_minimum_msat: 0,
5241 htlc_maximum_msat: 60_000,
5243 fee_proportional_millionths: 0,
5244 excess_data: Vec::new()
5246 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5247 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5248 short_channel_id: 13,
5251 cltv_expiry_delta: 0,
5252 htlc_minimum_msat: 0,
5253 htlc_maximum_msat: 60_000,
5255 fee_proportional_millionths: 0,
5256 excess_data: Vec::new()
5259 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5260 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5261 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5262 short_channel_id: 2,
5265 cltv_expiry_delta: 0,
5266 htlc_minimum_msat: 0,
5267 htlc_maximum_msat: 20_000,
5269 fee_proportional_millionths: 0,
5270 excess_data: Vec::new()
5272 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5273 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5274 short_channel_id: 4,
5277 cltv_expiry_delta: 0,
5278 htlc_minimum_msat: 0,
5279 htlc_maximum_msat: 20_000,
5281 fee_proportional_millionths: 0,
5282 excess_data: Vec::new()
5286 // Attempt to route more than available results in a failure.
5287 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5288 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
5289 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5290 } else { panic!(); }
5294 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5295 // Our algorithm should provide us with these 3 paths.
5296 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5297 assert_eq!(route.paths.len(), 3);
5298 let mut total_amount_paid_msat = 0;
5299 for path in &route.paths {
5300 assert_eq!(path.hops.len(), 2);
5301 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5302 total_amount_paid_msat += path.final_value_msat();
5304 assert_eq!(total_amount_paid_msat, 125_000);
5308 // Attempt to route without the last small cheap channel
5309 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5310 assert_eq!(route.paths.len(), 2);
5311 let mut total_amount_paid_msat = 0;
5312 for path in &route.paths {
5313 assert_eq!(path.hops.len(), 2);
5314 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5315 total_amount_paid_msat += path.final_value_msat();
5317 assert_eq!(total_amount_paid_msat, 90_000);
5322 fn min_criteria_consistency() {
5323 // Test that we don't use an inconsistent metric between updating and walking nodes during
5324 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5325 // was updated with a different criterion from the heap sorting, resulting in loops in
5326 // calculated paths. We test for that specific case here.
5328 // We construct a network that looks like this:
5330 // node2 -1(3)2- node3
5334 // node1 -1(5)2- node4 -1(1)2- node6
5340 // We create a loop on the side of our real path - our destination is node 6, with a
5341 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5342 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5343 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5344 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5345 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5346 // "previous hop" being set to node 3, creating a loop in the path.
5347 let secp_ctx = Secp256k1::new();
5348 let logger = Arc::new(ln_test_utils::TestLogger::new());
5349 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5350 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5351 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5352 let scorer = ln_test_utils::TestScorer::new();
5353 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5354 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5355 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5357 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5358 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5359 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5360 short_channel_id: 6,
5363 cltv_expiry_delta: (6 << 4) | 0,
5364 htlc_minimum_msat: 0,
5365 htlc_maximum_msat: MAX_VALUE_MSAT,
5367 fee_proportional_millionths: 0,
5368 excess_data: Vec::new()
5370 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5372 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5373 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5374 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5375 short_channel_id: 5,
5378 cltv_expiry_delta: (5 << 4) | 0,
5379 htlc_minimum_msat: 0,
5380 htlc_maximum_msat: MAX_VALUE_MSAT,
5382 fee_proportional_millionths: 0,
5383 excess_data: Vec::new()
5385 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5387 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5388 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5389 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5390 short_channel_id: 4,
5393 cltv_expiry_delta: (4 << 4) | 0,
5394 htlc_minimum_msat: 0,
5395 htlc_maximum_msat: MAX_VALUE_MSAT,
5397 fee_proportional_millionths: 0,
5398 excess_data: Vec::new()
5400 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5402 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5403 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5404 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5405 short_channel_id: 3,
5408 cltv_expiry_delta: (3 << 4) | 0,
5409 htlc_minimum_msat: 0,
5410 htlc_maximum_msat: MAX_VALUE_MSAT,
5412 fee_proportional_millionths: 0,
5413 excess_data: Vec::new()
5415 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5417 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5418 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5419 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5420 short_channel_id: 2,
5423 cltv_expiry_delta: (2 << 4) | 0,
5424 htlc_minimum_msat: 0,
5425 htlc_maximum_msat: MAX_VALUE_MSAT,
5427 fee_proportional_millionths: 0,
5428 excess_data: Vec::new()
5431 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5432 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5433 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5434 short_channel_id: 1,
5437 cltv_expiry_delta: (1 << 4) | 0,
5438 htlc_minimum_msat: 100,
5439 htlc_maximum_msat: MAX_VALUE_MSAT,
5441 fee_proportional_millionths: 0,
5442 excess_data: Vec::new()
5444 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5447 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5448 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5449 assert_eq!(route.paths.len(), 1);
5450 assert_eq!(route.paths[0].hops.len(), 3);
5452 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5453 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5454 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5455 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5456 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5457 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5459 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5460 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5461 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5462 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5463 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5464 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5466 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5467 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5468 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5469 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5470 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5471 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5477 fn exact_fee_liquidity_limit() {
5478 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5479 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5480 // we calculated fees on a higher value, resulting in us ignoring such paths.
5481 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5482 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5483 let scorer = ln_test_utils::TestScorer::new();
5484 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5485 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5486 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5488 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5490 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5491 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5492 short_channel_id: 2,
5495 cltv_expiry_delta: 0,
5496 htlc_minimum_msat: 0,
5497 htlc_maximum_msat: 85_000,
5499 fee_proportional_millionths: 0,
5500 excess_data: Vec::new()
5503 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5504 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5505 short_channel_id: 12,
5508 cltv_expiry_delta: (4 << 4) | 1,
5509 htlc_minimum_msat: 0,
5510 htlc_maximum_msat: 270_000,
5512 fee_proportional_millionths: 1000000,
5513 excess_data: Vec::new()
5517 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5518 // 200% fee charged channel 13 in the 1-to-2 direction.
5519 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5520 assert_eq!(route.paths.len(), 1);
5521 assert_eq!(route.paths[0].hops.len(), 2);
5523 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5524 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5525 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5526 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5527 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5528 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5530 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5531 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5532 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5533 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5534 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5535 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5540 fn htlc_max_reduction_below_min() {
5541 // Test that if, while walking the graph, we reduce the value being sent to meet an
5542 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5543 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5544 // resulting in us thinking there is no possible path, even if other paths exist.
5545 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5546 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5547 let scorer = ln_test_utils::TestScorer::new();
5548 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5549 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5550 let config = UserConfig::default();
5551 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5553 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5554 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5555 // then try to send 90_000.
5556 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5557 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5558 short_channel_id: 2,
5561 cltv_expiry_delta: 0,
5562 htlc_minimum_msat: 0,
5563 htlc_maximum_msat: 80_000,
5565 fee_proportional_millionths: 0,
5566 excess_data: Vec::new()
5568 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5569 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5570 short_channel_id: 4,
5573 cltv_expiry_delta: (4 << 4) | 1,
5574 htlc_minimum_msat: 90_000,
5575 htlc_maximum_msat: MAX_VALUE_MSAT,
5577 fee_proportional_millionths: 0,
5578 excess_data: Vec::new()
5582 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5583 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5584 // expensive) channels 12-13 path.
5585 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5586 assert_eq!(route.paths.len(), 1);
5587 assert_eq!(route.paths[0].hops.len(), 2);
5589 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5590 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5591 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5592 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5593 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5594 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5596 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5597 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5598 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5599 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5600 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5601 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5606 fn multiple_direct_first_hops() {
5607 // Previously we'd only ever considered one first hop path per counterparty.
5608 // However, as we don't restrict users to one channel per peer, we really need to support
5609 // looking at all first hop paths.
5610 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5611 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5612 // route over multiple channels with the same first hop.
5613 let secp_ctx = Secp256k1::new();
5614 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5615 let logger = Arc::new(ln_test_utils::TestLogger::new());
5616 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5617 let scorer = ln_test_utils::TestScorer::new();
5618 let config = UserConfig::default();
5619 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5620 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5621 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5624 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5625 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5626 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5627 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5628 assert_eq!(route.paths.len(), 1);
5629 assert_eq!(route.paths[0].hops.len(), 1);
5631 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5632 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5633 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5636 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5637 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5638 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5639 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5640 assert_eq!(route.paths.len(), 2);
5641 assert_eq!(route.paths[0].hops.len(), 1);
5642 assert_eq!(route.paths[1].hops.len(), 1);
5644 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5645 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5647 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5648 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5650 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5651 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5655 // If we have a bunch of outbound channels to the same node, where most are not
5656 // sufficient to pay the full payment, but one is, we should default to just using the
5657 // one single channel that has sufficient balance, avoiding MPP.
5659 // If we have several options above the 3xpayment value threshold, we should pick the
5660 // smallest of them, avoiding further fragmenting our available outbound balance to
5662 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5663 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5664 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5665 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5666 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5667 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5668 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5669 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5670 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5671 ]), 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5672 assert_eq!(route.paths.len(), 1);
5673 assert_eq!(route.paths[0].hops.len(), 1);
5675 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5676 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5677 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5682 fn prefers_shorter_route_with_higher_fees() {
5683 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5684 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5685 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5687 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5688 let scorer = ln_test_utils::TestScorer::new();
5689 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5690 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5691 let route = get_route(
5692 &our_id, &payment_params, &network_graph.read_only(), None, 100,
5693 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5695 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5697 assert_eq!(route.get_total_fees(), 100);
5698 assert_eq!(route.get_total_amount(), 100);
5699 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5701 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5702 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5703 let scorer = FixedPenaltyScorer::with_penalty(100);
5704 let route = get_route(
5705 &our_id, &payment_params, &network_graph.read_only(), None, 100,
5706 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5708 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5710 assert_eq!(route.get_total_fees(), 300);
5711 assert_eq!(route.get_total_amount(), 100);
5712 assert_eq!(path, vec![2, 4, 7, 10]);
5715 struct BadChannelScorer {
5716 short_channel_id: u64,
5720 impl Writeable for BadChannelScorer {
5721 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5723 impl Score for BadChannelScorer {
5724 type ScoreParams = ();
5725 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5726 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5729 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5730 fn payment_path_successful(&mut self, _path: &Path) {}
5731 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5732 fn probe_successful(&mut self, _path: &Path) {}
5735 struct BadNodeScorer {
5740 impl Writeable for BadNodeScorer {
5741 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5744 impl Score for BadNodeScorer {
5745 type ScoreParams = ();
5746 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
5747 if *target == self.node_id { u64::max_value() } else { 0 }
5750 fn payment_path_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5751 fn payment_path_successful(&mut self, _path: &Path) {}
5752 fn probe_failed(&mut self, _path: &Path, _short_channel_id: u64) {}
5753 fn probe_successful(&mut self, _path: &Path) {}
5757 fn avoids_routing_through_bad_channels_and_nodes() {
5758 let (secp_ctx, network, _, _, logger) = build_graph();
5759 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5760 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5761 let network_graph = network.read_only();
5763 // A path to nodes[6] exists when no penalties are applied to any channel.
5764 let scorer = ln_test_utils::TestScorer::new();
5765 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5766 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5767 let route = get_route(
5768 &our_id, &payment_params, &network_graph, None, 100,
5769 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5771 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5773 assert_eq!(route.get_total_fees(), 100);
5774 assert_eq!(route.get_total_amount(), 100);
5775 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5777 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5778 let scorer = BadChannelScorer { short_channel_id: 6 };
5779 let route = get_route(
5780 &our_id, &payment_params, &network_graph, None, 100,
5781 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5783 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5785 assert_eq!(route.get_total_fees(), 300);
5786 assert_eq!(route.get_total_amount(), 100);
5787 assert_eq!(path, vec![2, 4, 7, 10]);
5789 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5790 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5792 &our_id, &payment_params, &network_graph, None, 100,
5793 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
5795 Err(LightningError { err, .. } ) => {
5796 assert_eq!(err, "Failed to find a path to the given destination");
5798 Ok(_) => panic!("Expected error"),
5803 fn total_fees_single_path() {
5805 paths: vec![Path { hops: vec![
5807 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5808 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5809 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5812 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5813 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5814 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5817 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5818 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5819 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5821 ], blinded_tail: None }],
5822 payment_params: None,
5825 assert_eq!(route.get_total_fees(), 250);
5826 assert_eq!(route.get_total_amount(), 225);
5830 fn total_fees_multi_path() {
5832 paths: vec![Path { hops: vec![
5834 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5835 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5836 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5839 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5840 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5841 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5843 ], blinded_tail: None }, Path { hops: vec![
5845 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5846 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5847 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5850 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5851 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5852 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5854 ], blinded_tail: None }],
5855 payment_params: None,
5858 assert_eq!(route.get_total_fees(), 200);
5859 assert_eq!(route.get_total_amount(), 300);
5863 fn total_empty_route_no_panic() {
5864 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5865 // would both panic if the route was completely empty. We test to ensure they return 0
5866 // here, even though its somewhat nonsensical as a route.
5867 let route = Route { paths: Vec::new(), payment_params: None };
5869 assert_eq!(route.get_total_fees(), 0);
5870 assert_eq!(route.get_total_amount(), 0);
5874 fn limits_total_cltv_delta() {
5875 let (secp_ctx, network, _, _, logger) = build_graph();
5876 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5877 let network_graph = network.read_only();
5879 let scorer = ln_test_utils::TestScorer::new();
5881 // Make sure that generally there is at least one route available
5882 let feasible_max_total_cltv_delta = 1008;
5883 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5884 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5885 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5886 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5887 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5888 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5889 assert_ne!(path.len(), 0);
5891 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5892 let fail_max_total_cltv_delta = 23;
5893 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5894 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5895 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
5897 Err(LightningError { err, .. } ) => {
5898 assert_eq!(err, "Failed to find a path to the given destination");
5900 Ok(_) => panic!("Expected error"),
5905 fn avoids_recently_failed_paths() {
5906 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5907 // randomly inserting channels into it until we can't find a route anymore.
5908 let (secp_ctx, network, _, _, logger) = build_graph();
5909 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5910 let network_graph = network.read_only();
5912 let scorer = ln_test_utils::TestScorer::new();
5913 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
5914 .with_max_path_count(1);
5915 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5916 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5918 // We should be able to find a route initially, and then after we fail a few random
5919 // channels eventually we won't be able to any longer.
5920 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).is_ok());
5922 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes) {
5923 for chan in route.paths[0].hops.iter() {
5924 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5926 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5927 % route.paths[0].hops.len();
5928 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
5934 fn limits_path_length() {
5935 let (secp_ctx, network, _, _, logger) = build_line_graph();
5936 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5937 let network_graph = network.read_only();
5939 let scorer = ln_test_utils::TestScorer::new();
5940 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5941 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5943 // First check we can actually create a long route on this graph.
5944 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
5945 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100,
5946 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5947 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5948 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5950 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5951 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
5952 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100,
5953 Arc::clone(&logger), &scorer, &(), &random_seed_bytes)
5955 Err(LightningError { err, .. } ) => {
5956 assert_eq!(err, "Failed to find a path to the given destination");
5958 Ok(_) => panic!("Expected error"),
5963 fn adds_and_limits_cltv_offset() {
5964 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5965 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5967 let scorer = ln_test_utils::TestScorer::new();
5969 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5970 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5971 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5972 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
5973 assert_eq!(route.paths.len(), 1);
5975 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5977 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5978 let mut route_default = route.clone();
5979 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5980 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5981 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5982 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5983 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5985 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5986 let mut route_limited = route.clone();
5987 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5988 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5989 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5990 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5991 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5995 fn adds_plausible_cltv_offset() {
5996 let (secp_ctx, network, _, _, logger) = build_graph();
5997 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5998 let network_graph = network.read_only();
5999 let network_nodes = network_graph.nodes();
6000 let network_channels = network_graph.channels();
6001 let scorer = ln_test_utils::TestScorer::new();
6002 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6003 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6004 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6006 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100,
6007 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6008 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6010 let mut path_plausibility = vec![];
6012 for p in route.paths {
6013 // 1. Select random observation point
6014 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6015 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6017 prng.process_in_place(&mut random_bytes);
6018 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6019 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6021 // 2. Calculate what CLTV expiry delta we would observe there
6022 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6024 // 3. Starting from the observation point, find candidate paths
6025 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6026 candidates.push_back((observation_point, vec![]));
6028 let mut found_plausible_candidate = false;
6030 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6031 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6032 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6033 found_plausible_candidate = true;
6034 break 'candidate_loop;
6038 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6039 for channel_id in &cur_node.channels {
6040 if let Some(channel_info) = network_channels.get(&channel_id) {
6041 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6042 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6043 if cur_path_cltv_deltas.iter().sum::<u32>()
6044 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6045 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6046 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6047 candidates.push_back((*next_id, new_path_cltv_deltas));
6055 path_plausibility.push(found_plausible_candidate);
6057 assert!(path_plausibility.iter().all(|x| *x));
6061 fn builds_correct_path_from_hops() {
6062 let (secp_ctx, network, _, _, logger) = build_graph();
6063 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6064 let network_graph = network.read_only();
6066 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6067 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6069 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6070 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6071 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
6072 &network_graph, 100, Arc::clone(&logger), &random_seed_bytes).unwrap();
6073 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6074 assert_eq!(hops.len(), route.paths[0].hops.len());
6075 for (idx, hop_pubkey) in hops.iter().enumerate() {
6076 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6081 fn avoids_saturating_channels() {
6082 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6083 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6084 let decay_params = ProbabilisticScoringDecayParameters::default();
6085 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6087 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6088 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6089 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6090 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6091 short_channel_id: 4,
6094 cltv_expiry_delta: (4 << 4) | 1,
6095 htlc_minimum_msat: 0,
6096 htlc_maximum_msat: 250_000_000,
6098 fee_proportional_millionths: 0,
6099 excess_data: Vec::new()
6101 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6102 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6103 short_channel_id: 13,
6106 cltv_expiry_delta: (13 << 4) | 1,
6107 htlc_minimum_msat: 0,
6108 htlc_maximum_msat: 250_000_000,
6110 fee_proportional_millionths: 0,
6111 excess_data: Vec::new()
6114 let config = UserConfig::default();
6115 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6116 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6117 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6118 // 100,000 sats is less than the available liquidity on each channel, set above.
6119 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000_000, Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6120 assert_eq!(route.paths.len(), 2);
6121 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6122 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6125 #[cfg(not(feature = "no-std"))]
6126 pub(super) fn random_init_seed() -> u64 {
6127 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6128 use core::hash::{BuildHasher, Hasher};
6129 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6130 println!("Using seed of {}", seed);
6135 #[cfg(not(feature = "no-std"))]
6136 fn generate_routes() {
6137 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6139 let logger = ln_test_utils::TestLogger::new();
6140 let graph = match super::bench_utils::read_network_graph(&logger) {
6148 let params = ProbabilisticScoringFeeParameters::default();
6149 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6150 let features = super::Bolt11InvoiceFeatures::empty();
6152 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6156 #[cfg(not(feature = "no-std"))]
6157 fn generate_routes_mpp() {
6158 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6160 let logger = ln_test_utils::TestLogger::new();
6161 let graph = match super::bench_utils::read_network_graph(&logger) {
6169 let params = ProbabilisticScoringFeeParameters::default();
6170 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6171 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6173 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6177 #[cfg(not(feature = "no-std"))]
6178 fn generate_large_mpp_routes() {
6179 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6181 let logger = ln_test_utils::TestLogger::new();
6182 let graph = match super::bench_utils::read_network_graph(&logger) {
6190 let params = ProbabilisticScoringFeeParameters::default();
6191 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6192 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6194 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6198 fn honors_manual_penalties() {
6199 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6200 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6202 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6203 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6205 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6206 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6208 // First check set manual penalties are returned by the scorer.
6209 let usage = ChannelUsage {
6211 inflight_htlc_msat: 0,
6212 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6214 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6215 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6216 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6218 // Then check we can get a normal route
6219 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6220 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6221 assert!(route.is_ok());
6223 // Then check that we can't get a route if we ban an intermediate node.
6224 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6225 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6226 assert!(route.is_err());
6228 // Finally make sure we can route again, when we remove the ban.
6229 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6230 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, Arc::clone(&logger), &scorer, &scorer_params,&random_seed_bytes);
6231 assert!(route.is_ok());
6235 fn abide_by_route_hint_max_htlc() {
6236 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6237 // params in the final route.
6238 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6239 let netgraph = network_graph.read_only();
6240 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6241 let scorer = ln_test_utils::TestScorer::new();
6242 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6243 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6244 let config = UserConfig::default();
6246 let max_htlc_msat = 50_000;
6247 let route_hint_1 = RouteHint(vec![RouteHintHop {
6248 src_node_id: nodes[2],
6249 short_channel_id: 42,
6252 proportional_millionths: 0,
6254 cltv_expiry_delta: 10,
6255 htlc_minimum_msat: None,
6256 htlc_maximum_msat: Some(max_htlc_msat),
6258 let dest_node_id = ln_test_utils::pubkey(42);
6259 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6260 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6261 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6263 // Make sure we'll error if our route hints don't have enough liquidity according to their
6264 // htlc_maximum_msat.
6265 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6266 &payment_params, &netgraph, None, max_htlc_msat + 1, Arc::clone(&logger), &scorer, &(),
6269 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6270 } else { panic!(); }
6272 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6273 let mut route_hint_2 = route_hint_1.clone();
6274 route_hint_2.0[0].short_channel_id = 43;
6275 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6276 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6277 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6278 let route = get_route(&our_id, &payment_params, &netgraph, None, max_htlc_msat + 1,
6279 Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6280 assert_eq!(route.paths.len(), 2);
6281 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6282 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6286 fn direct_channel_to_hints_with_max_htlc() {
6287 // Check that if we have a first hop channel peer that's connected to multiple provided route
6288 // hints, that we properly split the payment between the route hints if needed.
6289 let logger = Arc::new(ln_test_utils::TestLogger::new());
6290 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6291 let scorer = ln_test_utils::TestScorer::new();
6292 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6293 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6294 let config = UserConfig::default();
6296 let our_node_id = ln_test_utils::pubkey(42);
6297 let intermed_node_id = ln_test_utils::pubkey(43);
6298 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6300 let amt_msat = 900_000;
6301 let max_htlc_msat = 500_000;
6302 let route_hint_1 = RouteHint(vec![RouteHintHop {
6303 src_node_id: intermed_node_id,
6304 short_channel_id: 44,
6307 proportional_millionths: 0,
6309 cltv_expiry_delta: 10,
6310 htlc_minimum_msat: None,
6311 htlc_maximum_msat: Some(max_htlc_msat),
6313 src_node_id: intermed_node_id,
6314 short_channel_id: 45,
6317 proportional_millionths: 0,
6319 cltv_expiry_delta: 10,
6320 htlc_minimum_msat: None,
6321 // Check that later route hint max htlcs don't override earlier ones
6322 htlc_maximum_msat: Some(max_htlc_msat - 50),
6324 let mut route_hint_2 = route_hint_1.clone();
6325 route_hint_2.0[0].short_channel_id = 46;
6326 route_hint_2.0[1].short_channel_id = 47;
6327 let dest_node_id = ln_test_utils::pubkey(44);
6328 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6329 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6330 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6332 let route = get_route(&our_node_id, &payment_params, &network_graph.read_only(),
6333 Some(&first_hop.iter().collect::<Vec<_>>()), amt_msat, Arc::clone(&logger), &scorer, &(),
6334 &random_seed_bytes).unwrap();
6335 assert_eq!(route.paths.len(), 2);
6336 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6337 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6338 assert_eq!(route.get_total_amount(), amt_msat);
6340 // Re-run but with two first hop channels connected to the same route hint peers that must be
6342 let first_hops = vec![
6343 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6344 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6346 let route = get_route(&our_node_id, &payment_params, &network_graph.read_only(),
6347 Some(&first_hops.iter().collect::<Vec<_>>()), amt_msat, Arc::clone(&logger), &scorer, &(),
6348 &random_seed_bytes).unwrap();
6349 assert_eq!(route.paths.len(), 2);
6350 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6351 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6352 assert_eq!(route.get_total_amount(), amt_msat);
6354 // Make sure this works for blinded route hints.
6355 let blinded_path = BlindedPath {
6356 introduction_node_id: intermed_node_id,
6357 blinding_point: ln_test_utils::pubkey(42),
6359 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6360 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6363 let blinded_payinfo = BlindedPayInfo {
6365 fee_proportional_millionths: 0,
6366 htlc_minimum_msat: 1,
6367 htlc_maximum_msat: max_htlc_msat,
6368 cltv_expiry_delta: 10,
6369 features: BlindedHopFeatures::empty(),
6371 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6372 let payment_params = PaymentParameters::blinded(vec![
6373 (blinded_payinfo.clone(), blinded_path.clone()),
6374 (blinded_payinfo.clone(), blinded_path.clone())])
6375 .with_bolt12_features(bolt12_features).unwrap();
6376 let route = get_route(&our_node_id, &payment_params, &network_graph.read_only(),
6377 Some(&first_hops.iter().collect::<Vec<_>>()), amt_msat, Arc::clone(&logger), &scorer, &(),
6378 &random_seed_bytes).unwrap();
6379 assert_eq!(route.paths.len(), 2);
6380 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6381 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6382 assert_eq!(route.get_total_amount(), amt_msat);
6386 fn blinded_route_ser() {
6387 let blinded_path_1 = BlindedPath {
6388 introduction_node_id: ln_test_utils::pubkey(42),
6389 blinding_point: ln_test_utils::pubkey(43),
6391 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6392 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6395 let blinded_path_2 = BlindedPath {
6396 introduction_node_id: ln_test_utils::pubkey(46),
6397 blinding_point: ln_test_utils::pubkey(47),
6399 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6400 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6403 // (De)serialize a Route with 1 blinded path out of two total paths.
6404 let mut route = Route { paths: vec![Path {
6405 hops: vec![RouteHop {
6406 pubkey: ln_test_utils::pubkey(50),
6407 node_features: NodeFeatures::empty(),
6408 short_channel_id: 42,
6409 channel_features: ChannelFeatures::empty(),
6411 cltv_expiry_delta: 0,
6413 blinded_tail: Some(BlindedTail {
6414 hops: blinded_path_1.blinded_hops,
6415 blinding_point: blinded_path_1.blinding_point,
6416 excess_final_cltv_expiry_delta: 40,
6417 final_value_msat: 100,
6419 hops: vec![RouteHop {
6420 pubkey: ln_test_utils::pubkey(51),
6421 node_features: NodeFeatures::empty(),
6422 short_channel_id: 43,
6423 channel_features: ChannelFeatures::empty(),
6425 cltv_expiry_delta: 0,
6426 }], blinded_tail: None }],
6427 payment_params: None,
6429 let encoded_route = route.encode();
6430 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6431 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6432 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6434 // (De)serialize a Route with two paths, each containing a blinded tail.
6435 route.paths[1].blinded_tail = Some(BlindedTail {
6436 hops: blinded_path_2.blinded_hops,
6437 blinding_point: blinded_path_2.blinding_point,
6438 excess_final_cltv_expiry_delta: 41,
6439 final_value_msat: 101,
6441 let encoded_route = route.encode();
6442 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6443 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6444 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6448 fn blinded_path_inflight_processing() {
6449 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6450 // account for the blinded tail's final amount_msat.
6451 let mut inflight_htlcs = InFlightHtlcs::new();
6452 let blinded_path = BlindedPath {
6453 introduction_node_id: ln_test_utils::pubkey(43),
6454 blinding_point: ln_test_utils::pubkey(48),
6455 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6458 hops: vec![RouteHop {
6459 pubkey: ln_test_utils::pubkey(42),
6460 node_features: NodeFeatures::empty(),
6461 short_channel_id: 42,
6462 channel_features: ChannelFeatures::empty(),
6464 cltv_expiry_delta: 0,
6467 pubkey: blinded_path.introduction_node_id,
6468 node_features: NodeFeatures::empty(),
6469 short_channel_id: 43,
6470 channel_features: ChannelFeatures::empty(),
6472 cltv_expiry_delta: 0,
6474 blinded_tail: Some(BlindedTail {
6475 hops: blinded_path.blinded_hops,
6476 blinding_point: blinded_path.blinding_point,
6477 excess_final_cltv_expiry_delta: 0,
6478 final_value_msat: 200,
6481 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6482 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6483 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6487 fn blinded_path_cltv_shadow_offset() {
6488 // Make sure we add a shadow offset when sending to blinded paths.
6489 let blinded_path = BlindedPath {
6490 introduction_node_id: ln_test_utils::pubkey(43),
6491 blinding_point: ln_test_utils::pubkey(44),
6493 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6494 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6497 let mut route = Route { paths: vec![Path {
6498 hops: vec![RouteHop {
6499 pubkey: ln_test_utils::pubkey(42),
6500 node_features: NodeFeatures::empty(),
6501 short_channel_id: 42,
6502 channel_features: ChannelFeatures::empty(),
6504 cltv_expiry_delta: 0,
6507 pubkey: blinded_path.introduction_node_id,
6508 node_features: NodeFeatures::empty(),
6509 short_channel_id: 43,
6510 channel_features: ChannelFeatures::empty(),
6512 cltv_expiry_delta: 0,
6515 blinded_tail: Some(BlindedTail {
6516 hops: blinded_path.blinded_hops,
6517 blinding_point: blinded_path.blinding_point,
6518 excess_final_cltv_expiry_delta: 0,
6519 final_value_msat: 200,
6521 }], payment_params: None};
6523 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6524 let (_, network_graph, _, _, _) = build_line_graph();
6525 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6526 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6527 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6531 fn simple_blinded_route_hints() {
6532 do_simple_blinded_route_hints(1);
6533 do_simple_blinded_route_hints(2);
6534 do_simple_blinded_route_hints(3);
6537 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6538 // Check that we can generate a route to a blinded path with the expected hops.
6539 let (secp_ctx, network, _, _, logger) = build_graph();
6540 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6541 let network_graph = network.read_only();
6543 let scorer = ln_test_utils::TestScorer::new();
6544 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6545 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6547 let mut blinded_path = BlindedPath {
6548 introduction_node_id: nodes[2],
6549 blinding_point: ln_test_utils::pubkey(42),
6550 blinded_hops: Vec::with_capacity(num_blinded_hops),
6552 for i in 0..num_blinded_hops {
6553 blinded_path.blinded_hops.push(
6554 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6557 let blinded_payinfo = BlindedPayInfo {
6559 fee_proportional_millionths: 500,
6560 htlc_minimum_msat: 1000,
6561 htlc_maximum_msat: 100_000_000,
6562 cltv_expiry_delta: 15,
6563 features: BlindedHopFeatures::empty(),
6566 let final_amt_msat = 1001;
6567 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6568 let route = get_route(&our_id, &payment_params, &network_graph, None, final_amt_msat , Arc::clone(&logger),
6569 &scorer, &(), &random_seed_bytes).unwrap();
6570 assert_eq!(route.paths.len(), 1);
6571 assert_eq!(route.paths[0].hops.len(), 2);
6573 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6574 assert_eq!(tail.hops, blinded_path.blinded_hops);
6575 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6576 assert_eq!(tail.final_value_msat, 1001);
6578 let final_hop = route.paths[0].hops.last().unwrap();
6579 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6580 if tail.hops.len() > 1 {
6581 assert_eq!(final_hop.fee_msat,
6582 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6583 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6585 assert_eq!(final_hop.fee_msat, 0);
6586 assert_eq!(final_hop.cltv_expiry_delta, 0);
6591 fn blinded_path_routing_errors() {
6592 // Check that we can generate a route to a blinded path with the expected hops.
6593 let (secp_ctx, network, _, _, logger) = build_graph();
6594 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6595 let network_graph = network.read_only();
6597 let scorer = ln_test_utils::TestScorer::new();
6598 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6599 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6601 let mut invalid_blinded_path = BlindedPath {
6602 introduction_node_id: nodes[2],
6603 blinding_point: ln_test_utils::pubkey(42),
6605 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
6608 let blinded_payinfo = BlindedPayInfo {
6610 fee_proportional_millionths: 500,
6611 htlc_minimum_msat: 1000,
6612 htlc_maximum_msat: 100_000_000,
6613 cltv_expiry_delta: 15,
6614 features: BlindedHopFeatures::empty(),
6617 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
6618 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
6619 let payment_params = PaymentParameters::blinded(vec![
6620 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
6621 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
6622 match get_route(&our_id, &payment_params, &network_graph, None, 1001, Arc::clone(&logger),
6623 &scorer, &(), &random_seed_bytes)
6625 Err(LightningError { err, .. }) => {
6626 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
6628 _ => panic!("Expected error")
6631 invalid_blinded_path.introduction_node_id = our_id;
6632 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
6633 match get_route(&our_id, &payment_params, &network_graph, None, 1001, Arc::clone(&logger),
6634 &scorer, &(), &random_seed_bytes)
6636 Err(LightningError { err, .. }) => {
6637 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
6639 _ => panic!("Expected error")
6642 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
6643 invalid_blinded_path.blinded_hops.clear();
6644 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
6645 match get_route(&our_id, &payment_params, &network_graph, None, 1001, Arc::clone(&logger),
6646 &scorer, &(), &random_seed_bytes)
6648 Err(LightningError { err, .. }) => {
6649 assert_eq!(err, "0-hop blinded path provided");
6651 _ => panic!("Expected error")
6656 fn matching_intro_node_paths_provided() {
6657 // Check that if multiple blinded paths with the same intro node are provided in payment
6658 // parameters, we'll return the correct paths in the resulting MPP route.
6659 let (secp_ctx, network, _, _, logger) = build_graph();
6660 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6661 let network_graph = network.read_only();
6663 let scorer = ln_test_utils::TestScorer::new();
6664 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6665 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6666 let config = UserConfig::default();
6668 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6669 let blinded_path_1 = BlindedPath {
6670 introduction_node_id: nodes[2],
6671 blinding_point: ln_test_utils::pubkey(42),
6673 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6674 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6677 let blinded_payinfo_1 = BlindedPayInfo {
6679 fee_proportional_millionths: 0,
6680 htlc_minimum_msat: 0,
6681 htlc_maximum_msat: 30_000,
6682 cltv_expiry_delta: 0,
6683 features: BlindedHopFeatures::empty(),
6686 let mut blinded_path_2 = blinded_path_1.clone();
6687 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
6688 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
6689 blinded_payinfo_2.htlc_maximum_msat = 70_000;
6691 let blinded_hints = vec![
6692 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
6693 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
6695 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
6696 .with_bolt12_features(bolt12_features.clone()).unwrap();
6698 let route = get_route(&our_id, &payment_params, &network_graph, None,
6699 100_000, Arc::clone(&logger), &scorer, &(), &random_seed_bytes).unwrap();
6700 assert_eq!(route.paths.len(), 2);
6701 let mut total_amount_paid_msat = 0;
6702 for path in route.paths.into_iter() {
6703 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
6704 if let Some(bt) = &path.blinded_tail {
6705 assert_eq!(bt.blinding_point,
6706 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
6707 .map(|(_, bp)| bp.blinding_point).unwrap());
6708 } else { panic!(); }
6709 total_amount_paid_msat += path.final_value_msat();
6711 assert_eq!(total_amount_paid_msat, 100_000);
6715 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
6716 pub(crate) mod bench_utils {
6720 use bitcoin::hashes::Hash;
6721 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
6723 use crate::chain::transaction::OutPoint;
6724 use crate::sign::{EntropySource, KeysManager};
6725 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
6726 use crate::ln::features::Bolt11InvoiceFeatures;
6727 use crate::routing::gossip::NetworkGraph;
6728 use crate::util::config::UserConfig;
6729 use crate::util::ser::ReadableArgs;
6730 use crate::util::test_utils::TestLogger;
6732 /// Tries to open a network graph file, or panics with a URL to fetch it.
6733 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
6734 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
6735 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
6736 .or_else(|_| { // Fall back to guessing based on the binary location
6737 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
6738 let mut path = std::env::current_exe().unwrap();
6739 path.pop(); // lightning-...
6741 path.pop(); // debug
6742 path.pop(); // target
6743 path.push("lightning");
6744 path.push("net_graph-2023-01-18.bin");
6747 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
6748 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
6749 let mut path = std::env::current_exe().unwrap();
6750 path.pop(); // bench...
6752 path.pop(); // debug
6753 path.pop(); // target
6754 path.pop(); // bench
6755 path.push("lightning");
6756 path.push("net_graph-2023-01-18.bin");
6759 .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");
6760 #[cfg(require_route_graph_test)]
6761 return Ok(res.unwrap());
6762 #[cfg(not(require_route_graph_test))]
6766 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
6767 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
6770 pub(crate) fn payer_pubkey() -> PublicKey {
6771 let secp_ctx = Secp256k1::new();
6772 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
6776 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
6778 channel_id: [0; 32],
6779 counterparty: ChannelCounterparty {
6780 features: channelmanager::provided_init_features(&UserConfig::default()),
6782 unspendable_punishment_reserve: 0,
6783 forwarding_info: None,
6784 outbound_htlc_minimum_msat: None,
6785 outbound_htlc_maximum_msat: None,
6787 funding_txo: Some(OutPoint {
6788 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
6791 short_channel_id: Some(1),
6792 inbound_scid_alias: None,
6793 outbound_scid_alias: None,
6794 channel_value_satoshis: 10_000_000_000,
6796 balance_msat: 10_000_000_000,
6797 outbound_capacity_msat: 10_000_000_000,
6798 next_outbound_htlc_minimum_msat: 0,
6799 next_outbound_htlc_limit_msat: 10_000_000_000,
6800 inbound_capacity_msat: 0,
6801 unspendable_punishment_reserve: None,
6802 confirmations_required: None,
6803 confirmations: None,
6804 force_close_spend_delay: None,
6806 is_channel_ready: true,
6809 inbound_htlc_minimum_msat: None,
6810 inbound_htlc_maximum_msat: None,
6812 feerate_sat_per_1000_weight: None,
6813 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
6817 pub(crate) fn generate_test_routes<S: Score>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
6818 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
6819 starting_amount: u64, route_count: usize,
6820 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
6821 let payer = payer_pubkey();
6822 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6823 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6825 let nodes = graph.read_only().nodes().clone();
6826 let mut route_endpoints = Vec::new();
6827 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
6828 // with some routes we picked being un-routable.
6829 for _ in 0..route_count * 3 / 2 {
6831 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6832 let src = PublicKey::from_slice(nodes.unordered_keys()
6833 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
6834 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6835 let dst = PublicKey::from_slice(nodes.unordered_keys()
6836 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
6837 let params = PaymentParameters::from_node_id(dst, 42)
6838 .with_bolt11_features(features.clone()).unwrap();
6839 let first_hop = first_hop(src);
6840 let amt = starting_amount + seed % 1_000_000;
6842 get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]),
6843 amt, &TestLogger::new(), &scorer, score_params, &random_seed_bytes).is_ok();
6845 // ...and seed the scorer with success and failure data...
6846 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6847 let mut score_amt = seed % 1_000_000_000;
6849 // Generate fail/success paths for a wider range of potential amounts with
6850 // MPP enabled to give us a chance to apply penalties for more potential
6852 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
6853 let params = PaymentParameters::from_node_id(dst, 42)
6854 .with_bolt11_features(mpp_features).unwrap();
6856 let route_res = get_route(&payer, ¶ms, &graph.read_only(),
6857 Some(&[&first_hop]), score_amt, &TestLogger::new(), &scorer,
6858 score_params, &random_seed_bytes);
6859 if let Ok(route) = route_res {
6860 for path in route.paths {
6861 if seed & 0x80 == 0 {
6862 scorer.payment_path_successful(&path);
6864 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
6865 scorer.payment_path_failed(&path, short_channel_id);
6867 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
6871 // If we couldn't find a path with a higer amount, reduce and try again.
6875 route_endpoints.push((first_hop, params, amt));
6881 // Because we've changed channel scores, it's possible we'll take different routes to the
6882 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
6883 // requires a too-high CLTV delta.
6884 route_endpoints.retain(|(first_hop, params, amt)| {
6885 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt,
6886 &TestLogger::new(), &scorer, score_params, &random_seed_bytes).is_ok()
6888 route_endpoints.truncate(route_count);
6889 assert_eq!(route_endpoints.len(), route_count);
6897 use crate::sign::{EntropySource, KeysManager};
6898 use crate::ln::channelmanager;
6899 use crate::ln::features::Bolt11InvoiceFeatures;
6900 use crate::routing::gossip::NetworkGraph;
6901 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
6902 use crate::util::config::UserConfig;
6903 use crate::util::logger::{Logger, Record};
6904 use crate::util::test_utils::TestLogger;
6906 use criterion::Criterion;
6908 struct DummyLogger {}
6909 impl Logger for DummyLogger {
6910 fn log(&self, _record: &Record) {}
6913 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
6914 let logger = TestLogger::new();
6915 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6916 let scorer = FixedPenaltyScorer::with_penalty(0);
6917 generate_routes(bench, &network_graph, scorer, &(), Bolt11InvoiceFeatures::empty(), 0,
6918 "generate_routes_with_zero_penalty_scorer");
6921 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
6922 let logger = TestLogger::new();
6923 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6924 let scorer = FixedPenaltyScorer::with_penalty(0);
6925 generate_routes(bench, &network_graph, scorer, &(),
6926 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
6927 "generate_mpp_routes_with_zero_penalty_scorer");
6930 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6931 let logger = TestLogger::new();
6932 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6933 let params = ProbabilisticScoringFeeParameters::default();
6934 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6935 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
6936 "generate_routes_with_probabilistic_scorer");
6939 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6940 let logger = TestLogger::new();
6941 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6942 let params = ProbabilisticScoringFeeParameters::default();
6943 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6944 generate_routes(bench, &network_graph, scorer, ¶ms,
6945 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
6946 "generate_mpp_routes_with_probabilistic_scorer");
6949 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
6950 let logger = TestLogger::new();
6951 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
6952 let params = ProbabilisticScoringFeeParameters::default();
6953 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
6954 generate_routes(bench, &network_graph, scorer, ¶ms,
6955 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
6956 "generate_large_mpp_routes_with_probabilistic_scorer");
6959 fn generate_routes<S: Score>(
6960 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
6961 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
6962 bench_name: &'static str,
6964 let payer = bench_utils::payer_pubkey();
6965 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6966 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6968 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
6969 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
6971 // ...then benchmark finding paths between the nodes we learned.
6973 bench.bench_function(bench_name, |b| b.iter(|| {
6974 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
6975 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt,
6976 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());