1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The router finds paths within a [`NetworkGraph`] for a payment.
12 use bitcoin::secp256k1::PublicKey;
13 use bitcoin::hashes::Hash;
14 use bitcoin::hashes::sha256::Hash as Sha256;
16 use crate::blinded_path::{BlindedHop, BlindedPath};
17 use crate::ln::PaymentHash;
18 use crate::ln::channelmanager::{ChannelDetails, PaymentId};
19 use crate::ln::features::{Bolt11InvoiceFeatures, Bolt12InvoiceFeatures, ChannelFeatures, NodeFeatures};
20 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
21 use crate::offers::invoice::{BlindedPayInfo, Bolt12Invoice};
22 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
23 use crate::routing::scoring::{ChannelUsage, LockableScore, ScoreLookUp};
24 use crate::util::ser::{Writeable, Readable, ReadableArgs, Writer};
25 use crate::util::logger::{Level, Logger};
26 use crate::util::chacha20::ChaCha20;
29 use crate::prelude::*;
30 use crate::sync::Mutex;
31 use alloc::collections::BinaryHeap;
35 /// A [`Router`] implemented using [`find_route`].
36 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> where
38 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
42 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> DefaultRouter<G, L, S, SP, Sc> where
49 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
51 /// Creates a new router.
52 pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S, score_params: SP) -> Self {
53 let random_seed_bytes = Mutex::new(random_seed_bytes);
54 Self { network_graph, logger, random_seed_bytes, scorer, score_params }
58 impl< G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>> Router for DefaultRouter<G, L, S, SP, Sc> where
60 S::Target: for <'a> LockableScore<'a, ScoreLookUp = Sc>,
65 params: &RouteParameters,
66 first_hops: Option<&[&ChannelDetails]>,
67 inflight_htlcs: InFlightHtlcs
68 ) -> Result<Route, LightningError> {
69 let random_seed_bytes = {
70 let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
71 *locked_random_seed_bytes = Sha256::hash(&*locked_random_seed_bytes).into_inner();
72 *locked_random_seed_bytes
75 payer, params, &self.network_graph, first_hops, &*self.logger,
76 &ScorerAccountingForInFlightHtlcs::new(self.scorer.read_lock(), &inflight_htlcs),
83 /// A trait defining behavior for routing a payment.
85 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
87 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
88 /// and [`RouteParameters::final_value_msat`], respectively.
90 &self, payer: &PublicKey, route_params: &RouteParameters,
91 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
92 ) -> Result<Route, LightningError>;
93 /// Finds a [`Route`] for a payment between the given `payer` and a payee.
95 /// The `payee` and the payment's value are given in [`RouteParameters::payment_params`]
96 /// and [`RouteParameters::final_value_msat`], respectively.
98 /// Includes a [`PaymentHash`] and a [`PaymentId`] to be able to correlate the request with a specific
100 fn find_route_with_id(
101 &self, payer: &PublicKey, route_params: &RouteParameters,
102 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
103 _payment_hash: PaymentHash, _payment_id: PaymentId
104 ) -> Result<Route, LightningError> {
105 self.find_route(payer, route_params, first_hops, inflight_htlcs)
109 /// [`ScoreLookUp`] implementation that factors in in-flight HTLC liquidity.
111 /// Useful for custom [`Router`] implementations to wrap their [`ScoreLookUp`] on-the-fly when calling
114 /// [`ScoreLookUp`]: crate::routing::scoring::ScoreLookUp
115 pub struct ScorerAccountingForInFlightHtlcs<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> {
117 // Maps a channel's short channel id and its direction to the liquidity used up.
118 inflight_htlcs: &'a InFlightHtlcs,
120 impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
121 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
122 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
123 ScorerAccountingForInFlightHtlcs {
131 impl<'a, SP: Sized, Sc: ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> Writeable for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
132 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
135 impl<'a, SP: Sized, Sc: 'a + ScoreLookUp<ScoreParams = SP>, S: Deref<Target = Sc>> ScoreLookUp for ScorerAccountingForInFlightHtlcs<'a, SP, Sc, S> {
136 type ScoreParams = Sc::ScoreParams;
137 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage, score_params: &Self::ScoreParams) -> u64 {
138 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
139 source, target, short_channel_id
141 let usage = ChannelUsage {
142 inflight_htlc_msat: usage.inflight_htlc_msat.saturating_add(used_liquidity),
146 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
148 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage, score_params)
153 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
154 /// in-use channel liquidity.
156 pub struct InFlightHtlcs(
157 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
158 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
159 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
161 HashMap<(u64, bool), u64>
165 /// Constructs an empty `InFlightHtlcs`.
166 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
168 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
169 pub fn process_path(&mut self, path: &Path, payer_node_id: PublicKey) {
170 if path.hops.is_empty() { return };
172 let mut cumulative_msat = 0;
173 if let Some(tail) = &path.blinded_tail {
174 cumulative_msat += tail.final_value_msat;
177 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
178 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
179 // the router excludes the payer node. In the following lines, the payer's information is
180 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
181 // in our sliding window of two.
182 let reversed_hops_with_payer = path.hops.iter().rev().skip(1)
183 .map(|hop| hop.pubkey)
184 .chain(core::iter::once(payer_node_id));
186 // Taking the reversed vector from above, we zip it with just the reversed hops list to
187 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
188 // the total amount sent.
189 for (next_hop, prev_hop) in path.hops.iter().rev().zip(reversed_hops_with_payer) {
190 cumulative_msat += next_hop.fee_msat;
192 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
193 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
194 .or_insert(cumulative_msat);
198 /// Adds a known HTLC given the public key of the HTLC source, target, and short channel
200 pub fn add_inflight_htlc(&mut self, source: &NodeId, target: &NodeId, channel_scid: u64, used_msat: u64){
202 .entry((channel_scid, source < target))
203 .and_modify(|used_liquidity_msat| *used_liquidity_msat += used_msat)
204 .or_insert(used_msat);
207 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
209 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
210 self.0.get(&(channel_scid, source < target)).map(|v| *v)
214 impl Writeable for InFlightHtlcs {
215 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
218 impl Readable for InFlightHtlcs {
219 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
220 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
221 Ok(Self(infight_map))
225 /// A hop in a route, and additional metadata about it. "Hop" is defined as a node and the channel
226 /// that leads to it.
227 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
228 pub struct RouteHop {
229 /// The node_id of the node at this hop.
230 pub pubkey: PublicKey,
231 /// The node_announcement features of the node at this hop. For the last hop, these may be
232 /// amended to match the features present in the invoice this node generated.
233 pub node_features: NodeFeatures,
234 /// The channel that should be used from the previous hop to reach this node.
235 pub short_channel_id: u64,
236 /// The channel_announcement features of the channel that should be used from the previous hop
237 /// to reach this node.
238 pub channel_features: ChannelFeatures,
239 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
240 /// If this is the last hop in [`Path::hops`]:
241 /// * if we're sending to a [`BlindedPath`], this is the fee paid for use of the entire blinded path
242 /// * otherwise, this is the full value of this [`Path`]'s part of the payment
244 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
246 /// The CLTV delta added for this hop.
247 /// If this is the last hop in [`Path::hops`]:
248 /// * if we're sending to a [`BlindedPath`], this is the CLTV delta for the entire blinded path
249 /// * otherwise, this is the CLTV delta expected at the destination
251 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
252 pub cltv_expiry_delta: u32,
253 /// Indicates whether this hop is possibly announced in the public network graph.
255 /// Will be `true` if there is a possibility that the channel is publicly known, i.e., if we
256 /// either know for sure it's announced in the public graph, or if any public channels exist
257 /// for which the given `short_channel_id` could be an alias for. Will be `false` if we believe
258 /// the channel to be unannounced.
260 /// Will be `true` for objects serialized with LDK version 0.0.116 and before.
261 pub maybe_announced_channel: bool,
264 impl_writeable_tlv_based!(RouteHop, {
265 (0, pubkey, required),
266 (1, maybe_announced_channel, (default_value, true)),
267 (2, node_features, required),
268 (4, short_channel_id, required),
269 (6, channel_features, required),
270 (8, fee_msat, required),
271 (10, cltv_expiry_delta, required),
274 /// The blinded portion of a [`Path`], if we're routing to a recipient who provided blinded paths in
275 /// their [`Bolt12Invoice`].
277 /// [`Bolt12Invoice`]: crate::offers::invoice::Bolt12Invoice
278 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
279 pub struct BlindedTail {
280 /// The hops of the [`BlindedPath`] provided by the recipient.
282 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
283 pub hops: Vec<BlindedHop>,
284 /// The blinding point of the [`BlindedPath`] provided by the recipient.
286 /// [`BlindedPath`]: crate::blinded_path::BlindedPath
287 pub blinding_point: PublicKey,
288 /// Excess CLTV delta added to the recipient's CLTV expiry to deter intermediate nodes from
289 /// inferring the destination. May be 0.
290 pub excess_final_cltv_expiry_delta: u32,
291 /// The total amount paid on this [`Path`], excluding the fees.
292 pub final_value_msat: u64,
295 impl_writeable_tlv_based!(BlindedTail, {
296 (0, hops, required_vec),
297 (2, blinding_point, required),
298 (4, excess_final_cltv_expiry_delta, required),
299 (6, final_value_msat, required),
302 /// A path in a [`Route`] to the payment recipient. Must always be at least length one.
303 /// If no [`Path::blinded_tail`] is present, then [`Path::hops`] length may be up to 19.
304 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
306 /// The list of unblinded hops in this [`Path`]. Must be at least length one.
307 pub hops: Vec<RouteHop>,
308 /// The blinded path at which this path terminates, if we're sending to one, and its metadata.
309 pub blinded_tail: Option<BlindedTail>,
313 /// Gets the fees for a given path, excluding any excess paid to the recipient.
314 pub fn fee_msat(&self) -> u64 {
315 match &self.blinded_tail {
316 Some(_) => self.hops.iter().map(|hop| hop.fee_msat).sum::<u64>(),
318 // Do not count last hop of each path since that's the full value of the payment
319 self.hops.split_last().map_or(0,
320 |(_, path_prefix)| path_prefix.iter().map(|hop| hop.fee_msat).sum())
325 /// Gets the total amount paid on this [`Path`], excluding the fees.
326 pub fn final_value_msat(&self) -> u64 {
327 match &self.blinded_tail {
328 Some(blinded_tail) => blinded_tail.final_value_msat,
329 None => self.hops.last().map_or(0, |hop| hop.fee_msat)
333 /// Gets the final hop's CLTV expiry delta.
334 pub fn final_cltv_expiry_delta(&self) -> Option<u32> {
335 match &self.blinded_tail {
337 None => self.hops.last().map(|hop| hop.cltv_expiry_delta)
342 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
343 /// it can take multiple paths. Each path is composed of one or more hops through the network.
344 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
346 /// The list of [`Path`]s taken for a single (potentially-)multi-part payment. If no
347 /// [`BlindedTail`]s are present, then the pubkey of the last [`RouteHop`] in each path must be
349 pub paths: Vec<Path>,
350 /// The `route_params` parameter passed to [`find_route`].
352 /// This is used by `ChannelManager` to track information which may be required for retries.
354 /// Will be `None` for objects serialized with LDK versions prior to 0.0.117.
355 pub route_params: Option<RouteParameters>,
359 /// Returns the total amount of fees paid on this [`Route`].
361 /// For objects serialized with LDK 0.0.117 and after, this includes any extra payment made to
362 /// the recipient, which can happen in excess of the amount passed to [`find_route`] via
363 /// [`RouteParameters::final_value_msat`], if we had to reach the [`htlc_minimum_msat`] limits.
365 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
366 pub fn get_total_fees(&self) -> u64 {
367 let overpaid_value_msat = self.route_params.as_ref()
368 .map_or(0, |p| self.get_total_amount().saturating_sub(p.final_value_msat));
369 overpaid_value_msat + self.paths.iter().map(|path| path.fee_msat()).sum::<u64>()
372 /// Returns the total amount paid on this [`Route`], excluding the fees.
374 /// Might be more than requested as part of the given [`RouteParameters::final_value_msat`] if
375 /// we had to reach the [`htlc_minimum_msat`] limits.
377 /// [`htlc_minimum_msat`]: https://github.com/lightning/bolts/blob/master/07-routing-gossip.md#the-channel_update-message
378 pub fn get_total_amount(&self) -> u64 {
379 self.paths.iter().map(|path| path.final_value_msat()).sum()
383 impl fmt::Display for Route {
384 fn fmt(&self, f: &mut fmt::Formatter) -> Result<(), fmt::Error> {
385 log_route!(self).fmt(f)
389 const SERIALIZATION_VERSION: u8 = 1;
390 const MIN_SERIALIZATION_VERSION: u8 = 1;
392 impl Writeable for Route {
393 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
394 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
395 (self.paths.len() as u64).write(writer)?;
396 let mut blinded_tails = Vec::new();
397 for path in self.paths.iter() {
398 (path.hops.len() as u8).write(writer)?;
399 for (idx, hop) in path.hops.iter().enumerate() {
401 if let Some(blinded_tail) = &path.blinded_tail {
402 if blinded_tails.is_empty() {
403 blinded_tails = Vec::with_capacity(path.hops.len());
405 blinded_tails.push(None);
408 blinded_tails.push(Some(blinded_tail));
409 } else if !blinded_tails.is_empty() { blinded_tails.push(None); }
412 write_tlv_fields!(writer, {
413 // For compatibility with LDK versions prior to 0.0.117, we take the individual
414 // RouteParameters' fields and reconstruct them on read.
415 (1, self.route_params.as_ref().map(|p| &p.payment_params), option),
416 (2, blinded_tails, optional_vec),
417 (3, self.route_params.as_ref().map(|p| p.final_value_msat), option),
418 (5, self.route_params.as_ref().map(|p| p.max_total_routing_fee_msat), option),
424 impl Readable for Route {
425 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
426 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
427 let path_count: u64 = Readable::read(reader)?;
428 if path_count == 0 { return Err(DecodeError::InvalidValue); }
429 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
430 let mut min_final_cltv_expiry_delta = u32::max_value();
431 for _ in 0..path_count {
432 let hop_count: u8 = Readable::read(reader)?;
433 let mut hops: Vec<RouteHop> = Vec::with_capacity(hop_count as usize);
434 for _ in 0..hop_count {
435 hops.push(Readable::read(reader)?);
437 if hops.is_empty() { return Err(DecodeError::InvalidValue); }
438 min_final_cltv_expiry_delta =
439 cmp::min(min_final_cltv_expiry_delta, hops.last().unwrap().cltv_expiry_delta);
440 paths.push(Path { hops, blinded_tail: None });
442 _init_and_read_len_prefixed_tlv_fields!(reader, {
443 (1, payment_params, (option: ReadableArgs, min_final_cltv_expiry_delta)),
444 (2, blinded_tails, optional_vec),
445 (3, final_value_msat, option),
446 (5, max_total_routing_fee_msat, option)
448 let blinded_tails = blinded_tails.unwrap_or(Vec::new());
449 if blinded_tails.len() != 0 {
450 if blinded_tails.len() != paths.len() { return Err(DecodeError::InvalidValue) }
451 for (path, blinded_tail_opt) in paths.iter_mut().zip(blinded_tails.into_iter()) {
452 path.blinded_tail = blinded_tail_opt;
456 // If we previously wrote the corresponding fields, reconstruct RouteParameters.
457 let route_params = match (payment_params, final_value_msat) {
458 (Some(payment_params), Some(final_value_msat)) => {
459 Some(RouteParameters { payment_params, final_value_msat, max_total_routing_fee_msat })
464 Ok(Route { paths, route_params })
468 /// Parameters needed to find a [`Route`].
470 /// Passed to [`find_route`] and [`build_route_from_hops`].
471 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
472 pub struct RouteParameters {
473 /// The parameters of the failed payment path.
474 pub payment_params: PaymentParameters,
476 /// The amount in msats sent on the failed payment path.
477 pub final_value_msat: u64,
479 /// The maximum total fees, in millisatoshi, that may accrue during route finding.
481 /// This limit also applies to the total fees that may arise while retrying failed payment
484 /// Note that values below a few sats may result in some paths being spuriously ignored.
485 pub max_total_routing_fee_msat: Option<u64>,
488 impl RouteParameters {
489 /// Constructs [`RouteParameters`] from the given [`PaymentParameters`] and a payment amount.
491 /// [`Self::max_total_routing_fee_msat`] defaults to 1% of the payment amount + 50 sats
492 pub fn from_payment_params_and_value(payment_params: PaymentParameters, final_value_msat: u64) -> Self {
493 Self { payment_params, final_value_msat, max_total_routing_fee_msat: Some(final_value_msat / 100 + 50_000) }
497 impl Writeable for RouteParameters {
498 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
499 write_tlv_fields!(writer, {
500 (0, self.payment_params, required),
501 (1, self.max_total_routing_fee_msat, option),
502 (2, self.final_value_msat, required),
503 // LDK versions prior to 0.0.114 had the `final_cltv_expiry_delta` parameter in
504 // `RouteParameters` directly. For compatibility, we write it here.
505 (4, self.payment_params.payee.final_cltv_expiry_delta(), option),
511 impl Readable for RouteParameters {
512 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
513 _init_and_read_len_prefixed_tlv_fields!(reader, {
514 (0, payment_params, (required: ReadableArgs, 0)),
515 (1, max_total_routing_fee_msat, option),
516 (2, final_value_msat, required),
517 (4, final_cltv_delta, option),
519 let mut payment_params: PaymentParameters = payment_params.0.unwrap();
520 if let Payee::Clear { ref mut final_cltv_expiry_delta, .. } = payment_params.payee {
521 if final_cltv_expiry_delta == &0 {
522 *final_cltv_expiry_delta = final_cltv_delta.ok_or(DecodeError::InvalidValue)?;
527 final_value_msat: final_value_msat.0.unwrap(),
528 max_total_routing_fee_msat,
533 /// Maximum total CTLV difference we allow for a full payment path.
534 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
536 /// Maximum number of paths we allow an (MPP) payment to have.
537 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
538 // limits, but for now more than 10 paths likely carries too much one-path failure.
539 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
541 const DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF: u8 = 2;
543 // The median hop CLTV expiry delta currently seen in the network.
544 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
546 // During routing, we only consider paths shorter than our maximum length estimate.
547 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
548 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
549 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
551 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
552 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
553 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
554 // (payment_secret and total_msat) = 93 bytes for the final hop.
555 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
556 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
557 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
559 /// Information used to route a payment.
560 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
561 pub struct PaymentParameters {
562 /// Information about the payee, such as their features and route hints for their channels.
565 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
566 pub expiry_time: Option<u64>,
568 /// The maximum total CLTV delta we accept for the route.
569 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
570 pub max_total_cltv_expiry_delta: u32,
572 /// The maximum number of paths that may be used by (MPP) payments.
573 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
574 pub max_path_count: u8,
576 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
577 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
578 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
579 /// increasing failure probability for those paths.
581 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
582 /// restriction have been found. While paths which meet this criteria will be searched for, it
583 /// is ultimately up to the scorer to select them over other paths.
585 /// A value of 0 will allow payments up to and including a channel's total announced usable
586 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
589 pub max_channel_saturation_power_of_half: u8,
591 /// A list of SCIDs which this payment was previously attempted over and which caused the
592 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
594 pub previously_failed_channels: Vec<u64>,
597 impl Writeable for PaymentParameters {
598 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
599 let mut clear_hints = &vec![];
600 let mut blinded_hints = &vec![];
602 Payee::Clear { route_hints, .. } => clear_hints = route_hints,
603 Payee::Blinded { route_hints, .. } => blinded_hints = route_hints,
605 write_tlv_fields!(writer, {
606 (0, self.payee.node_id(), option),
607 (1, self.max_total_cltv_expiry_delta, required),
608 (2, self.payee.features(), option),
609 (3, self.max_path_count, required),
610 (4, *clear_hints, required_vec),
611 (5, self.max_channel_saturation_power_of_half, required),
612 (6, self.expiry_time, option),
613 (7, self.previously_failed_channels, required_vec),
614 (8, *blinded_hints, optional_vec),
615 (9, self.payee.final_cltv_expiry_delta(), option),
621 impl ReadableArgs<u32> for PaymentParameters {
622 fn read<R: io::Read>(reader: &mut R, default_final_cltv_expiry_delta: u32) -> Result<Self, DecodeError> {
623 _init_and_read_len_prefixed_tlv_fields!(reader, {
624 (0, payee_pubkey, option),
625 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
626 (2, features, (option: ReadableArgs, payee_pubkey.is_some())),
627 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
628 (4, clear_route_hints, required_vec),
629 (5, max_channel_saturation_power_of_half, (default_value, DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF)),
630 (6, expiry_time, option),
631 (7, previously_failed_channels, optional_vec),
632 (8, blinded_route_hints, optional_vec),
633 (9, final_cltv_expiry_delta, (default_value, default_final_cltv_expiry_delta)),
635 let blinded_route_hints = blinded_route_hints.unwrap_or(vec![]);
636 let payee = if blinded_route_hints.len() != 0 {
637 if clear_route_hints.len() != 0 || payee_pubkey.is_some() { return Err(DecodeError::InvalidValue) }
639 route_hints: blinded_route_hints,
640 features: features.and_then(|f: Features| f.bolt12()),
644 route_hints: clear_route_hints,
645 node_id: payee_pubkey.ok_or(DecodeError::InvalidValue)?,
646 features: features.and_then(|f| f.bolt11()),
647 final_cltv_expiry_delta: final_cltv_expiry_delta.0.unwrap(),
651 max_total_cltv_expiry_delta: _init_tlv_based_struct_field!(max_total_cltv_expiry_delta, (default_value, unused)),
652 max_path_count: _init_tlv_based_struct_field!(max_path_count, (default_value, unused)),
654 max_channel_saturation_power_of_half: _init_tlv_based_struct_field!(max_channel_saturation_power_of_half, (default_value, unused)),
656 previously_failed_channels: previously_failed_channels.unwrap_or(Vec::new()),
662 impl PaymentParameters {
663 /// Creates a payee with the node id of the given `pubkey`.
665 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
667 pub fn from_node_id(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32) -> Self {
669 payee: Payee::Clear { node_id: payee_pubkey, route_hints: vec![], features: None, final_cltv_expiry_delta },
671 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
672 max_path_count: DEFAULT_MAX_PATH_COUNT,
673 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
674 previously_failed_channels: Vec::new(),
678 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
680 /// The `final_cltv_expiry_delta` should match the expected final CLTV delta the recipient has
683 /// Note that MPP keysend is not widely supported yet. The `allow_mpp` lets you choose
684 /// whether your router will be allowed to find a multi-part route for this payment. If you
685 /// set `allow_mpp` to true, you should ensure a payment secret is set on send, likely via
686 /// [`RecipientOnionFields::secret_only`].
688 /// [`RecipientOnionFields::secret_only`]: crate::ln::channelmanager::RecipientOnionFields::secret_only
689 pub fn for_keysend(payee_pubkey: PublicKey, final_cltv_expiry_delta: u32, allow_mpp: bool) -> Self {
690 Self::from_node_id(payee_pubkey, final_cltv_expiry_delta)
691 .with_bolt11_features(Bolt11InvoiceFeatures::for_keysend(allow_mpp))
692 .expect("PaymentParameters::from_node_id should always initialize the payee as unblinded")
695 /// Creates parameters for paying to a blinded payee from the provided invoice. Sets
696 /// [`Payee::Blinded::route_hints`], [`Payee::Blinded::features`], and
697 /// [`PaymentParameters::expiry_time`].
698 pub fn from_bolt12_invoice(invoice: &Bolt12Invoice) -> Self {
699 Self::blinded(invoice.payment_paths().to_vec())
700 .with_bolt12_features(invoice.invoice_features().clone()).unwrap()
701 .with_expiry_time(invoice.created_at().as_secs().saturating_add(invoice.relative_expiry().as_secs()))
704 /// Creates parameters for paying to a blinded payee from the provided blinded route hints.
705 pub fn blinded(blinded_route_hints: Vec<(BlindedPayInfo, BlindedPath)>) -> Self {
707 payee: Payee::Blinded { route_hints: blinded_route_hints, features: None },
709 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
710 max_path_count: DEFAULT_MAX_PATH_COUNT,
711 max_channel_saturation_power_of_half: DEFAULT_MAX_CHANNEL_SATURATION_POW_HALF,
712 previously_failed_channels: Vec::new(),
716 /// Includes the payee's features. Errors if the parameters were not initialized with
717 /// [`PaymentParameters::from_bolt12_invoice`].
719 /// This is not exported to bindings users since bindings don't support move semantics
720 pub fn with_bolt12_features(self, features: Bolt12InvoiceFeatures) -> Result<Self, ()> {
722 Payee::Clear { .. } => Err(()),
723 Payee::Blinded { route_hints, .. } =>
724 Ok(Self { payee: Payee::Blinded { route_hints, features: Some(features) }, ..self })
728 /// Includes the payee's features. Errors if the parameters were initialized with
729 /// [`PaymentParameters::from_bolt12_invoice`].
731 /// This is not exported to bindings users since bindings don't support move semantics
732 pub fn with_bolt11_features(self, features: Bolt11InvoiceFeatures) -> Result<Self, ()> {
734 Payee::Blinded { .. } => Err(()),
735 Payee::Clear { route_hints, node_id, final_cltv_expiry_delta, .. } =>
737 payee: Payee::Clear {
738 route_hints, node_id, features: Some(features), final_cltv_expiry_delta
744 /// Includes hints for routing to the payee. Errors if the parameters were initialized with
745 /// [`PaymentParameters::from_bolt12_invoice`].
747 /// This is not exported to bindings users since bindings don't support move semantics
748 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Result<Self, ()> {
750 Payee::Blinded { .. } => Err(()),
751 Payee::Clear { node_id, features, final_cltv_expiry_delta, .. } =>
753 payee: Payee::Clear {
754 route_hints, node_id, features, final_cltv_expiry_delta,
760 /// Includes a payment expiration in seconds relative to the UNIX epoch.
762 /// This is not exported to bindings users since bindings don't support move semantics
763 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
764 Self { expiry_time: Some(expiry_time), ..self }
767 /// Includes a limit for the total CLTV expiry delta which is considered during routing
769 /// This is not exported to bindings users since bindings don't support move semantics
770 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
771 Self { max_total_cltv_expiry_delta, ..self }
774 /// Includes a limit for the maximum number of payment paths that may be used.
776 /// This is not exported to bindings users since bindings don't support move semantics
777 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
778 Self { max_path_count, ..self }
781 /// Includes a limit for the maximum share of a channel's total capacity that can be sent over, as
782 /// a power of 1/2. See [`PaymentParameters::max_channel_saturation_power_of_half`].
784 /// This is not exported to bindings users since bindings don't support move semantics
785 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
786 Self { max_channel_saturation_power_of_half, ..self }
790 /// The recipient of a payment, differing based on whether they've hidden their identity with route
792 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
794 /// The recipient provided blinded paths and payinfo to reach them. The blinded paths themselves
795 /// will be included in the final [`Route`].
797 /// Aggregated routing info and blinded paths, for routing to the payee without knowing their
799 route_hints: Vec<(BlindedPayInfo, BlindedPath)>,
800 /// Features supported by the payee.
802 /// May be set from the payee's invoice. May be `None` if the invoice does not contain any
804 features: Option<Bolt12InvoiceFeatures>,
806 /// The recipient included these route hints in their BOLT11 invoice.
808 /// The node id of the payee.
810 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
811 route_hints: Vec<RouteHint>,
812 /// Features supported by the payee.
814 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
815 /// does not contain any features.
817 /// [`for_keysend`]: PaymentParameters::for_keysend
818 features: Option<Bolt11InvoiceFeatures>,
819 /// The minimum CLTV delta at the end of the route. This value must not be zero.
820 final_cltv_expiry_delta: u32,
825 fn node_id(&self) -> Option<PublicKey> {
827 Self::Clear { node_id, .. } => Some(*node_id),
831 fn node_features(&self) -> Option<NodeFeatures> {
833 Self::Clear { features, .. } => features.as_ref().map(|f| f.to_context()),
834 Self::Blinded { features, .. } => features.as_ref().map(|f| f.to_context()),
837 fn supports_basic_mpp(&self) -> bool {
839 Self::Clear { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
840 Self::Blinded { features, .. } => features.as_ref().map_or(false, |f| f.supports_basic_mpp()),
843 fn features(&self) -> Option<FeaturesRef> {
845 Self::Clear { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt11(f)),
846 Self::Blinded { features, .. } => features.as_ref().map(|f| FeaturesRef::Bolt12(f)),
849 fn final_cltv_expiry_delta(&self) -> Option<u32> {
851 Self::Clear { final_cltv_expiry_delta, .. } => Some(*final_cltv_expiry_delta),
855 fn blinded_route_hints(&self) -> &[(BlindedPayInfo, BlindedPath)] {
857 Self::Blinded { route_hints, .. } => &route_hints[..],
858 Self::Clear { .. } => &[]
862 fn unblinded_route_hints(&self) -> &[RouteHint] {
864 Self::Blinded { .. } => &[],
865 Self::Clear { route_hints, .. } => &route_hints[..]
870 enum FeaturesRef<'a> {
871 Bolt11(&'a Bolt11InvoiceFeatures),
872 Bolt12(&'a Bolt12InvoiceFeatures),
875 Bolt11(Bolt11InvoiceFeatures),
876 Bolt12(Bolt12InvoiceFeatures),
880 fn bolt12(self) -> Option<Bolt12InvoiceFeatures> {
882 Self::Bolt12(f) => Some(f),
886 fn bolt11(self) -> Option<Bolt11InvoiceFeatures> {
888 Self::Bolt11(f) => Some(f),
894 impl<'a> Writeable for FeaturesRef<'a> {
895 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
897 Self::Bolt11(f) => Ok(f.write(w)?),
898 Self::Bolt12(f) => Ok(f.write(w)?),
903 impl ReadableArgs<bool> for Features {
904 fn read<R: io::Read>(reader: &mut R, bolt11: bool) -> Result<Self, DecodeError> {
905 if bolt11 { return Ok(Self::Bolt11(Readable::read(reader)?)) }
906 Ok(Self::Bolt12(Readable::read(reader)?))
910 /// A list of hops along a payment path terminating with a channel to the recipient.
911 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
912 pub struct RouteHint(pub Vec<RouteHintHop>);
914 impl Writeable for RouteHint {
915 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
916 (self.0.len() as u64).write(writer)?;
917 for hop in self.0.iter() {
924 impl Readable for RouteHint {
925 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
926 let hop_count: u64 = Readable::read(reader)?;
927 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
928 for _ in 0..hop_count {
929 hops.push(Readable::read(reader)?);
935 /// A channel descriptor for a hop along a payment path.
936 #[derive(Clone, Debug, Hash, Eq, PartialEq, Ord, PartialOrd)]
937 pub struct RouteHintHop {
938 /// The node_id of the non-target end of the route
939 pub src_node_id: PublicKey,
940 /// The short_channel_id of this channel
941 pub short_channel_id: u64,
942 /// The fees which must be paid to use this channel
943 pub fees: RoutingFees,
944 /// The difference in CLTV values between this node and the next node.
945 pub cltv_expiry_delta: u16,
946 /// The minimum value, in msat, which must be relayed to the next hop.
947 pub htlc_minimum_msat: Option<u64>,
948 /// The maximum value in msat available for routing with a single HTLC.
949 pub htlc_maximum_msat: Option<u64>,
952 impl_writeable_tlv_based!(RouteHintHop, {
953 (0, src_node_id, required),
954 (1, htlc_minimum_msat, option),
955 (2, short_channel_id, required),
956 (3, htlc_maximum_msat, option),
958 (6, cltv_expiry_delta, required),
961 #[derive(Eq, PartialEq)]
962 struct RouteGraphNode {
964 lowest_fee_to_node: u64,
965 total_cltv_delta: u32,
966 // The maximum value a yet-to-be-constructed payment path might flow through this node.
967 // This value is upper-bounded by us by:
968 // - how much is needed for a path being constructed
969 // - how much value can channels following this node (up to the destination) can contribute,
970 // considering their capacity and fees
971 value_contribution_msat: u64,
972 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
973 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
974 path_htlc_minimum_msat: u64,
975 /// All penalties incurred from this hop on the way to the destination, as calculated using
977 path_penalty_msat: u64,
978 /// The number of hops walked up to this node.
979 path_length_to_node: u8,
982 impl cmp::Ord for RouteGraphNode {
983 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
984 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
985 .saturating_add(other.path_penalty_msat);
986 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
987 .saturating_add(self.path_penalty_msat);
988 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
992 impl cmp::PartialOrd for RouteGraphNode {
993 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
994 Some(self.cmp(other))
998 /// A wrapper around the various hop representations.
1000 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
1001 #[derive(Clone, Debug)]
1002 enum CandidateRouteHop<'a> {
1003 /// A hop from the payer, where the outbound liquidity is known.
1005 details: &'a ChannelDetails,
1007 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
1009 info: DirectedChannelInfo<'a>,
1010 short_channel_id: u64,
1012 /// A hop to the payee found in the BOLT 11 payment invoice, though not necessarily a direct
1015 hint: &'a RouteHintHop,
1017 /// The payee's identity is concealed behind blinded paths provided in a BOLT 12 invoice.
1019 hint: &'a (BlindedPayInfo, BlindedPath),
1022 /// Similar to [`Self::Blinded`], but the path here has 1 blinded hop. `BlindedPayInfo` provided
1023 /// for 1-hop blinded paths is ignored because it is meant to apply to the hops *between* the
1024 /// introduction node and the destination. Useful for tracking that we need to include a blinded
1025 /// path at the end of our [`Route`].
1027 hint: &'a (BlindedPayInfo, BlindedPath),
1032 impl<'a> CandidateRouteHop<'a> {
1033 fn short_channel_id(&self) -> Option<u64> {
1035 CandidateRouteHop::FirstHop { details } => Some(details.get_outbound_payment_scid().unwrap()),
1036 CandidateRouteHop::PublicHop { short_channel_id, .. } => Some(*short_channel_id),
1037 CandidateRouteHop::PrivateHop { hint } => Some(hint.short_channel_id),
1038 CandidateRouteHop::Blinded { .. } => None,
1039 CandidateRouteHop::OneHopBlinded { .. } => None,
1043 // NOTE: This may alloc memory so avoid calling it in a hot code path.
1044 fn features(&self) -> ChannelFeatures {
1046 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
1047 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
1048 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
1049 CandidateRouteHop::Blinded { .. } => ChannelFeatures::empty(),
1050 CandidateRouteHop::OneHopBlinded { .. } => ChannelFeatures::empty(),
1054 fn cltv_expiry_delta(&self) -> u32 {
1056 CandidateRouteHop::FirstHop { .. } => 0,
1057 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
1058 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
1059 CandidateRouteHop::Blinded { hint, .. } => hint.0.cltv_expiry_delta as u32,
1060 CandidateRouteHop::OneHopBlinded { .. } => 0,
1064 fn htlc_minimum_msat(&self) -> u64 {
1066 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_minimum_msat,
1067 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
1068 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
1069 CandidateRouteHop::Blinded { hint, .. } => hint.0.htlc_minimum_msat,
1070 CandidateRouteHop::OneHopBlinded { .. } => 0,
1074 fn fees(&self) -> RoutingFees {
1076 CandidateRouteHop::FirstHop { .. } => RoutingFees {
1077 base_msat: 0, proportional_millionths: 0,
1079 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
1080 CandidateRouteHop::PrivateHop { hint } => hint.fees,
1081 CandidateRouteHop::Blinded { hint, .. } => {
1083 base_msat: hint.0.fee_base_msat,
1084 proportional_millionths: hint.0.fee_proportional_millionths
1087 CandidateRouteHop::OneHopBlinded { .. } =>
1088 RoutingFees { base_msat: 0, proportional_millionths: 0 },
1092 fn effective_capacity(&self) -> EffectiveCapacity {
1094 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
1095 liquidity_msat: details.next_outbound_htlc_limit_msat,
1097 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
1098 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: Some(max), .. }} =>
1099 EffectiveCapacity::HintMaxHTLC { amount_msat: *max },
1100 CandidateRouteHop::PrivateHop { hint: RouteHintHop { htlc_maximum_msat: None, .. }} =>
1101 EffectiveCapacity::Infinite,
1102 CandidateRouteHop::Blinded { hint, .. } =>
1103 EffectiveCapacity::HintMaxHTLC { amount_msat: hint.0.htlc_maximum_msat },
1104 CandidateRouteHop::OneHopBlinded { .. } => EffectiveCapacity::Infinite,
1108 fn id(&self, channel_direction: bool /* src_node_id < target_node_id */) -> CandidateHopId {
1110 CandidateRouteHop::Blinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1111 CandidateRouteHop::OneHopBlinded { hint_idx, .. } => CandidateHopId::Blinded(*hint_idx),
1112 _ => CandidateHopId::Clear((self.short_channel_id().unwrap(), channel_direction)),
1115 fn blinded_path(&self) -> Option<&'a BlindedPath> {
1117 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1125 #[derive(Clone, Copy, Eq, Hash, Ord, PartialOrd, PartialEq)]
1126 enum CandidateHopId {
1127 /// Contains (scid, src_node_id < target_node_id)
1129 /// Index of the blinded route hint in [`Payee::Blinded::route_hints`].
1134 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
1135 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
1137 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
1138 EffectiveCapacity::Infinite => u64::max_value(),
1139 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
1140 EffectiveCapacity::AdvertisedMaxHTLC { amount_msat } =>
1141 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
1142 // Treat htlc_maximum_msat from a route hint as an exact liquidity amount, since the invoice is
1143 // expected to have been generated from up-to-date capacity information.
1144 EffectiveCapacity::HintMaxHTLC { amount_msat } => amount_msat,
1145 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
1146 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
1150 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
1151 -> bool where I1::Item: PartialEq<I2::Item> {
1153 let a = iter_a.next();
1154 let b = iter_b.next();
1155 if a.is_none() && b.is_none() { return true; }
1156 if a.is_none() || b.is_none() { return false; }
1157 if a.unwrap().ne(&b.unwrap()) { return false; }
1161 /// It's useful to keep track of the hops associated with the fees required to use them,
1162 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
1163 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
1164 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
1166 struct PathBuildingHop<'a> {
1167 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
1168 // is a larger refactor and will require careful performance analysis.
1170 candidate: CandidateRouteHop<'a>,
1173 /// All the fees paid *after* this channel on the way to the destination
1174 next_hops_fee_msat: u64,
1175 /// Fee paid for the use of the current channel (see candidate.fees()).
1176 /// The value will be actually deducted from the counterparty balance on the previous link.
1177 hop_use_fee_msat: u64,
1178 /// Used to compare channels when choosing the for routing.
1179 /// Includes paying for the use of a hop and the following hops, as well as
1180 /// an estimated cost of reaching this hop.
1181 /// Might get stale when fees are recomputed. Primarily for internal use.
1182 total_fee_msat: u64,
1183 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
1184 /// walk and may be invalid thereafter.
1185 path_htlc_minimum_msat: u64,
1186 /// All penalties incurred from this channel on the way to the destination, as calculated using
1187 /// channel scoring.
1188 path_penalty_msat: u64,
1189 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
1190 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
1191 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
1192 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
1193 /// avoid processing them again.
1194 was_processed: bool,
1195 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1196 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
1197 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
1198 // value_contribution_msat, which requires tracking it here. See comments below where it is
1199 // used for more info.
1200 value_contribution_msat: u64,
1203 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
1204 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
1205 let mut debug_struct = f.debug_struct("PathBuildingHop");
1207 .field("node_id", &self.node_id)
1208 .field("short_channel_id", &self.candidate.short_channel_id())
1209 .field("total_fee_msat", &self.total_fee_msat)
1210 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
1211 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
1212 .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)))
1213 .field("path_penalty_msat", &self.path_penalty_msat)
1214 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
1215 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
1216 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1217 let debug_struct = debug_struct
1218 .field("value_contribution_msat", &self.value_contribution_msat);
1219 debug_struct.finish()
1223 // Instantiated with a list of hops with correct data in them collected during path finding,
1224 // an instance of this struct should be further modified only via given methods.
1226 struct PaymentPath<'a> {
1227 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
1230 impl<'a> PaymentPath<'a> {
1231 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
1232 fn get_value_msat(&self) -> u64 {
1233 self.hops.last().unwrap().0.fee_msat
1236 fn get_path_penalty_msat(&self) -> u64 {
1237 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
1240 fn get_total_fee_paid_msat(&self) -> u64 {
1241 if self.hops.len() < 1 {
1245 // Can't use next_hops_fee_msat because it gets outdated.
1246 for (i, (hop, _)) in self.hops.iter().enumerate() {
1247 if i != self.hops.len() - 1 {
1248 result += hop.fee_msat;
1254 fn get_cost_msat(&self) -> u64 {
1255 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
1258 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
1259 // to change fees may result in an inconsistency.
1261 // Sometimes we call this function right after constructing a path which is inconsistent in
1262 // that it the value being transferred has decreased while we were doing path finding, leading
1263 // to the fees being paid not lining up with the actual limits.
1265 // Note that this function is not aware of the available_liquidity limit, and thus does not
1266 // support increasing the value being transferred beyond what was selected during the initial
1269 // Returns the amount that this path contributes to the total payment value, which may be greater
1270 // than `value_msat` if we had to overpay to meet the final node's `htlc_minimum_msat`.
1271 fn update_value_and_recompute_fees(&mut self, value_msat: u64) -> u64 {
1272 let mut extra_contribution_msat = 0;
1273 let mut total_fee_paid_msat = 0 as u64;
1274 for i in (0..self.hops.len()).rev() {
1275 let last_hop = i == self.hops.len() - 1;
1277 // For non-last-hop, this value will represent the fees paid on the current hop. It
1278 // will consist of the fees for the use of the next hop, and extra fees to match
1279 // htlc_minimum_msat of the current channel. Last hop is handled separately.
1280 let mut cur_hop_fees_msat = 0;
1282 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
1285 let cur_hop = &mut self.hops.get_mut(i).unwrap().0;
1286 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
1287 cur_hop.path_penalty_msat += extra_contribution_msat;
1288 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
1289 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
1290 // set it too high just to maliciously take more fees by exploiting this
1291 // match htlc_minimum_msat logic.
1292 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
1293 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
1294 // Note that there is a risk that *previous hops* (those closer to us, as we go
1295 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
1297 // This might make us end up with a broken route, although this should be super-rare
1298 // in practice, both because of how healthy channels look like, and how we pick
1299 // channels in add_entry.
1300 // Also, this can't be exploited more heavily than *announce a free path and fail
1302 cur_hop_transferred_amount_msat += extra_fees_msat;
1304 // We remember and return the extra fees on the final hop to allow accounting for
1305 // them in the path's value contribution.
1307 extra_contribution_msat = extra_fees_msat;
1309 total_fee_paid_msat += extra_fees_msat;
1310 cur_hop_fees_msat += extra_fees_msat;
1315 // Final hop is a special case: it usually has just value_msat (by design), but also
1316 // it still could overpay for the htlc_minimum_msat.
1317 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
1319 // Propagate updated fees for the use of the channels to one hop back, where they
1320 // will be actually paid (fee_msat). The last hop is handled above separately.
1321 cur_hop.fee_msat = cur_hop_fees_msat;
1324 // Fee for the use of the current hop which will be deducted on the previous hop.
1325 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
1326 // this channel is free for us.
1328 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
1329 cur_hop.hop_use_fee_msat = new_fee;
1330 total_fee_paid_msat += new_fee;
1332 // It should not be possible because this function is called only to reduce the
1333 // value. In that case, compute_fee was already called with the same fees for
1334 // larger amount and there was no overflow.
1339 value_msat + extra_contribution_msat
1344 /// Calculate the fees required to route the given amount over a channel with the given fees.
1345 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
1346 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1347 .and_then(|part| (channel_fees.base_msat as u64).checked_add(part / 1_000_000))
1351 /// Calculate the fees required to route the given amount over a channel with the given fees,
1352 /// saturating to [`u64::max_value`].
1353 fn compute_fees_saturating(amount_msat: u64, channel_fees: RoutingFees) -> u64 {
1354 amount_msat.checked_mul(channel_fees.proportional_millionths as u64)
1355 .map(|prop| prop / 1_000_000).unwrap_or(u64::max_value())
1356 .saturating_add(channel_fees.base_msat as u64)
1359 /// The default `features` we assume for a node in a route, when no `features` are known about that
1362 /// Default features are:
1363 /// * variable_length_onion_optional
1364 fn default_node_features() -> NodeFeatures {
1365 let mut features = NodeFeatures::empty();
1366 features.set_variable_length_onion_optional();
1370 struct LoggedPayeePubkey(Option<PublicKey>);
1371 impl fmt::Display for LoggedPayeePubkey {
1372 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1375 "payee node id ".fmt(f)?;
1379 "blinded payee".fmt(f)
1385 struct LoggedCandidateHop<'a>(&'a CandidateRouteHop<'a>);
1386 impl<'a> fmt::Display for LoggedCandidateHop<'a> {
1387 fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
1389 CandidateRouteHop::Blinded { hint, .. } | CandidateRouteHop::OneHopBlinded { hint, .. } => {
1390 "blinded route hint with introduction node id ".fmt(f)?;
1391 hint.1.introduction_node_id.fmt(f)?;
1392 " and blinding point ".fmt(f)?;
1393 hint.1.blinding_point.fmt(f)
1395 CandidateRouteHop::FirstHop { .. } => {
1396 "first hop with SCID ".fmt(f)?;
1397 self.0.short_channel_id().unwrap().fmt(f)
1399 CandidateRouteHop::PrivateHop { .. } => {
1400 "route hint with SCID ".fmt(f)?;
1401 self.0.short_channel_id().unwrap().fmt(f)
1405 self.0.short_channel_id().unwrap().fmt(f)
1412 fn sort_first_hop_channels(
1413 channels: &mut Vec<&ChannelDetails>, used_liquidities: &HashMap<CandidateHopId, u64>,
1414 recommended_value_msat: u64, our_node_pubkey: &PublicKey
1416 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1417 // most like to use.
1419 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1420 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1423 // Second, because simply always sorting in descending order would always use our largest
1424 // available outbound capacity, needlessly fragmenting our available channel capacities,
1425 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1426 // which have enough, but not too much, capacity for the payment.
1428 // Available outbound balances factor in liquidity already reserved for previously found paths.
1429 channels.sort_unstable_by(|chan_a, chan_b| {
1430 let chan_a_outbound_limit_msat = chan_a.next_outbound_htlc_limit_msat
1431 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_a.get_outbound_payment_scid().unwrap(),
1432 our_node_pubkey < &chan_a.counterparty.node_id))).unwrap_or(&0));
1433 let chan_b_outbound_limit_msat = chan_b.next_outbound_htlc_limit_msat
1434 .saturating_sub(*used_liquidities.get(&CandidateHopId::Clear((chan_b.get_outbound_payment_scid().unwrap(),
1435 our_node_pubkey < &chan_b.counterparty.node_id))).unwrap_or(&0));
1436 if chan_b_outbound_limit_msat < recommended_value_msat || chan_a_outbound_limit_msat < recommended_value_msat {
1437 // Sort in descending order
1438 chan_b_outbound_limit_msat.cmp(&chan_a_outbound_limit_msat)
1440 // Sort in ascending order
1441 chan_a_outbound_limit_msat.cmp(&chan_b_outbound_limit_msat)
1446 /// Finds a route from us (payer) to the given target node (payee).
1448 /// If the payee provided features in their invoice, they should be provided via the `payee` field
1449 /// in the given [`RouteParameters::payment_params`].
1450 /// Without this, MPP will only be used if the payee's features are available in the network graph.
1452 /// Private routing paths between a public node and the target may be included in the `payee` field
1453 /// of [`RouteParameters::payment_params`].
1455 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
1456 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
1457 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
1459 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
1460 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
1461 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
1465 /// Panics if first_hops contains channels without `short_channel_id`s;
1466 /// [`ChannelManager::list_usable_channels`] will never include such channels.
1468 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
1469 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
1470 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
1471 pub fn find_route<L: Deref, GL: Deref, S: ScoreLookUp>(
1472 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
1473 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
1474 scorer: &S, score_params: &S::ScoreParams, random_seed_bytes: &[u8; 32]
1475 ) -> Result<Route, LightningError>
1476 where L::Target: Logger, GL::Target: Logger {
1477 let graph_lock = network_graph.read_only();
1478 let mut route = get_route(our_node_pubkey, &route_params, &graph_lock, first_hops, logger,
1479 scorer, score_params, random_seed_bytes)?;
1480 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1484 pub(crate) fn get_route<L: Deref, S: ScoreLookUp>(
1485 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network_graph: &ReadOnlyNetworkGraph,
1486 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, score_params: &S::ScoreParams,
1487 _random_seed_bytes: &[u8; 32]
1488 ) -> Result<Route, LightningError>
1489 where L::Target: Logger {
1491 let payment_params = &route_params.payment_params;
1492 let final_value_msat = route_params.final_value_msat;
1493 // If we're routing to a blinded recipient, we won't have their node id. Therefore, keep the
1494 // unblinded payee id as an option. We also need a non-optional "payee id" for path construction,
1495 // so use a dummy id for this in the blinded case.
1496 let payee_node_id_opt = payment_params.payee.node_id().map(|pk| NodeId::from_pubkey(&pk));
1497 const DUMMY_BLINDED_PAYEE_ID: [u8; 33] = [2; 33];
1498 let maybe_dummy_payee_pk = payment_params.payee.node_id().unwrap_or_else(|| PublicKey::from_slice(&DUMMY_BLINDED_PAYEE_ID).unwrap());
1499 let maybe_dummy_payee_node_id = NodeId::from_pubkey(&maybe_dummy_payee_pk);
1500 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
1502 if payee_node_id_opt.map_or(false, |payee| payee == our_node_id) {
1503 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
1505 if our_node_id == maybe_dummy_payee_node_id {
1506 return Err(LightningError{err: "Invalid origin node id provided, use a different one".to_owned(), action: ErrorAction::IgnoreError});
1509 if final_value_msat > MAX_VALUE_MSAT {
1510 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
1513 if final_value_msat == 0 {
1514 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
1517 match &payment_params.payee {
1518 Payee::Clear { route_hints, node_id, .. } => {
1519 for route in route_hints.iter() {
1520 for hop in &route.0 {
1521 if hop.src_node_id == *node_id {
1522 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
1527 Payee::Blinded { route_hints, .. } => {
1528 if route_hints.iter().all(|(_, path)| &path.introduction_node_id == our_node_pubkey) {
1529 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});
1531 for (_, blinded_path) in route_hints.iter() {
1532 if blinded_path.blinded_hops.len() == 0 {
1533 return Err(LightningError{err: "0-hop blinded path provided".to_owned(), action: ErrorAction::IgnoreError});
1534 } else if &blinded_path.introduction_node_id == our_node_pubkey {
1535 log_info!(logger, "Got blinded path with ourselves as the introduction node, ignoring");
1536 } else if blinded_path.blinded_hops.len() == 1 &&
1537 route_hints.iter().any( |(_, p)| p.blinded_hops.len() == 1
1538 && p.introduction_node_id != blinded_path.introduction_node_id)
1540 return Err(LightningError{err: format!("1-hop blinded paths must all have matching introduction node ids"), action: ErrorAction::IgnoreError});
1545 let final_cltv_expiry_delta = payment_params.payee.final_cltv_expiry_delta().unwrap_or(0);
1546 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
1547 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});
1550 // The general routing idea is the following:
1551 // 1. Fill first/last hops communicated by the caller.
1552 // 2. Attempt to construct a path from payer to payee for transferring
1553 // any ~sufficient (described later) value.
1554 // If succeed, remember which channels were used and how much liquidity they have available,
1555 // so that future paths don't rely on the same liquidity.
1556 // 3. Proceed to the next step if:
1557 // - we hit the recommended target value;
1558 // - OR if we could not construct a new path. Any next attempt will fail too.
1559 // Otherwise, repeat step 2.
1560 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1561 // (not recommended value).
1562 // 5. If yes, proceed. If not, fail routing.
1563 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1564 // transferred up to the transfer target value.
1565 // 7. Reduce the value of the last path until we are sending only the target value.
1566 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1567 // them so that we're not sending two HTLCs along the same path.
1569 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1570 // distance from the payee
1572 // We are not a faithful Dijkstra's implementation because we can change values which impact
1573 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1574 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1575 // the value we are currently attempting to send over a path, we simply reduce the value being
1576 // sent along the path for any hops after that channel. This may imply that later fees (which
1577 // we've already tabulated) are lower because a smaller value is passing through the channels
1578 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1579 // channels which were selected earlier (and which may still be used for other paths without a
1580 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1583 // One potentially problematic case for this algorithm would be if there are many
1584 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1585 // graph walking), we may never find a path which is not liquidity-limited and has lower
1586 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1587 // Because we only consider paths with at least 5% of the total value being sent, the damage
1588 // from such a case should be limited, however this could be further reduced in the future by
1589 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1590 // limits for the purposes of fee calculation.
1592 // Alternatively, we could store more detailed path information in the heap (targets, below)
1593 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1594 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1595 // and practically (as we would need to store dynamically-allocated path information in heap
1596 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1597 // results of such an algorithm would likely be biased towards lower-value paths.
1599 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1600 // outside of our current search value, running a path search more times to gather candidate
1601 // paths at different values. While this may be acceptable, further path searches may increase
1602 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1603 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1604 // the same time, remaining generic across different payment values.
1606 let network_channels = network_graph.channels();
1607 let network_nodes = network_graph.nodes();
1609 if payment_params.max_path_count == 0 {
1610 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1613 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1614 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1616 let allow_mpp = if payment_params.max_path_count == 1 {
1618 } else if payment_params.payee.supports_basic_mpp() {
1620 } else if let Some(payee) = payee_node_id_opt {
1621 network_nodes.get(&payee).map_or(false, |node| node.announcement_info.as_ref().map_or(false,
1622 |info| info.features.supports_basic_mpp()))
1625 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1626 LoggedPayeePubkey(payment_params.payee.node_id()), if allow_mpp { "with" } else { "without" },
1627 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1630 // Prepare the data we'll use for payee-to-payer search by
1631 // inserting first hops suggested by the caller as targets.
1632 // Our search will then attempt to reach them while traversing from the payee node.
1633 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1634 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1635 if let Some(hops) = first_hops {
1637 if chan.get_outbound_payment_scid().is_none() {
1638 panic!("first_hops should be filled in with usable channels, not pending ones");
1640 if chan.counterparty.node_id == *our_node_pubkey {
1641 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1644 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1645 .or_insert(Vec::new())
1648 if first_hop_targets.is_empty() {
1649 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1653 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1654 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1655 // adding duplicate entries when we find a better path to a given node.
1656 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1658 // Map from node_id to information about the best current path to that node, including feerate
1660 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1662 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1663 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1664 // htlc_minimum with extra fees while still finding a cheaper path.
1665 let mut hit_minimum_limit;
1667 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1668 // We start with a path_value of the exact amount we want, and if that generates a route we may
1669 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1670 // amount we want in total across paths, selecting the best subset at the end.
1671 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1672 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1673 let mut path_value_msat = final_value_msat;
1675 // Routing Fragmentation Mitigation heuristic:
1677 // Routing fragmentation across many payment paths increases the overall routing
1678 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1679 // Taking too many smaller paths also increases the chance of payment failure.
1680 // Thus to avoid this effect, we require from our collected links to provide
1681 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1682 // This requirement is currently set to be 1/max_path_count of the payment
1683 // value to ensure we only ever return routes that do not violate this limit.
1684 let minimal_value_contribution_msat: u64 = if allow_mpp {
1685 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1690 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1691 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1692 // drop the requirement by setting this to 0.
1693 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1695 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1696 // determine if the channel can be used by additional MPP paths or to inform path finding
1697 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1698 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1700 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1701 HashMap::with_capacity(network_nodes.len());
1703 // Keeping track of how much value we already collected across other paths. Helps to decide
1704 // when we want to stop looking for new paths.
1705 let mut already_collected_value_msat = 0;
1707 for (_, channels) in first_hop_targets.iter_mut() {
1708 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1712 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1713 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1715 // Remember how many candidates we ignored to allow for some logging afterwards.
1716 let mut num_ignored_value_contribution: u32 = 0;
1717 let mut num_ignored_path_length_limit: u32 = 0;
1718 let mut num_ignored_cltv_delta_limit: u32 = 0;
1719 let mut num_ignored_previously_failed: u32 = 0;
1720 let mut num_ignored_total_fee_limit: u32 = 0;
1721 let mut num_ignored_avoid_overpayment: u32 = 0;
1722 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
1724 macro_rules! add_entry {
1725 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1726 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1727 // since that value has to be transferred over this channel.
1728 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1729 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1730 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1731 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1732 // We "return" whether we updated the path at the end, and how much we can route via
1733 // this channel, via this:
1734 let mut hop_contribution_amt_msat = None;
1735 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1736 // practice these cases should be caught earlier:
1737 // - for regular channels at channel announcement (TODO)
1738 // - for first and last hops early in get_route
1739 if $src_node_id != $dest_node_id {
1740 let scid_opt = $candidate.short_channel_id();
1741 let effective_capacity = $candidate.effective_capacity();
1742 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1744 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1745 // It may be misleading because we might later choose to reduce the value transferred
1746 // over these channels, and the channel which was insufficient might become sufficient.
1747 // Worst case: we drop a good channel here because it can't cover the high following
1748 // fees caused by one expensive channel, but then this channel could have been used
1749 // if the amount being transferred over this path is lower.
1750 // We do this for now, but this is a subject for removal.
1751 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1752 let used_liquidity_msat = used_liquidities
1753 .get(&$candidate.id($src_node_id < $dest_node_id))
1754 .map_or(0, |used_liquidity_msat| {
1755 available_value_contribution_msat = available_value_contribution_msat
1756 .saturating_sub(*used_liquidity_msat);
1757 *used_liquidity_msat
1760 // Verify the liquidity offered by this channel complies to the minimal contribution.
1761 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1762 // Do not consider candidate hops that would exceed the maximum path length.
1763 let path_length_to_node = $next_hops_path_length + 1;
1764 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1766 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1767 // In order to already account for some of the privacy enhancing random CLTV
1768 // expiry delta offset we add on top later, we subtract a rough estimate
1769 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1770 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1771 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1772 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1773 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1774 .saturating_add($candidate.cltv_expiry_delta());
1775 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1777 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1778 // Includes paying fees for the use of the following channels.
1779 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1780 Some(result) => result,
1781 // Can't overflow due to how the values were computed right above.
1782 None => unreachable!(),
1784 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1785 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1786 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1788 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1789 let may_overpay_to_meet_path_minimum_msat =
1790 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1791 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
1792 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1793 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
1795 let payment_failed_on_this_channel = scid_opt.map_or(false,
1796 |scid| payment_params.previously_failed_channels.contains(&scid));
1798 let should_log_candidate = match $candidate {
1799 CandidateRouteHop::FirstHop { .. } => true,
1800 CandidateRouteHop::PrivateHop { .. } => true,
1801 CandidateRouteHop::Blinded { .. } => true,
1802 CandidateRouteHop::OneHopBlinded { .. } => true,
1806 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1807 // bother considering this channel. If retrying with recommended_value_msat may
1808 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1809 // around again with a higher amount.
1810 if !contributes_sufficient_value {
1811 if should_log_candidate {
1812 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1814 num_ignored_value_contribution += 1;
1815 } else if exceeds_max_path_length {
1816 if should_log_candidate {
1817 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1819 num_ignored_path_length_limit += 1;
1820 } else if exceeds_cltv_delta_limit {
1821 if should_log_candidate {
1822 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1824 num_ignored_cltv_delta_limit += 1;
1825 } else if payment_failed_on_this_channel {
1826 if should_log_candidate {
1827 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1829 num_ignored_previously_failed += 1;
1830 } else if may_overpay_to_meet_path_minimum_msat {
1831 if should_log_candidate {
1833 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
1834 LoggedCandidateHop(&$candidate));
1836 num_ignored_avoid_overpayment += 1;
1837 hit_minimum_limit = true;
1838 } else if over_path_minimum_msat {
1839 // Note that low contribution here (limited by available_liquidity_msat)
1840 // might violate htlc_minimum_msat on the hops which are next along the
1841 // payment path (upstream to the payee). To avoid that, we recompute
1842 // path fees knowing the final path contribution after constructing it.
1843 let curr_min = cmp::max(
1844 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
1846 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
1847 .saturating_add(curr_min);
1848 let hm_entry = dist.entry($src_node_id);
1849 let old_entry = hm_entry.or_insert_with(|| {
1850 // If there was previously no known way to access the source node
1851 // (recall it goes payee-to-payer) of short_channel_id, first add a
1852 // semi-dummy record just to compute the fees to reach the source node.
1853 // This will affect our decision on selecting short_channel_id
1854 // as a way to reach the $dest_node_id.
1856 node_id: $dest_node_id.clone(),
1857 candidate: $candidate.clone(),
1859 next_hops_fee_msat: u64::max_value(),
1860 hop_use_fee_msat: u64::max_value(),
1861 total_fee_msat: u64::max_value(),
1862 path_htlc_minimum_msat,
1863 path_penalty_msat: u64::max_value(),
1864 was_processed: false,
1865 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1866 value_contribution_msat,
1870 #[allow(unused_mut)] // We only use the mut in cfg(test)
1871 let mut should_process = !old_entry.was_processed;
1872 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1874 // In test/fuzzing builds, we do extra checks to make sure the skipping
1875 // of already-seen nodes only happens in cases we expect (see below).
1876 if !should_process { should_process = true; }
1880 let mut hop_use_fee_msat = 0;
1881 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1883 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1884 // will have the same effective-fee
1885 if $src_node_id != our_node_id {
1886 // Note that `u64::max_value` means we'll always fail the
1887 // `old_entry.total_fee_msat > total_fee_msat` check below
1888 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1889 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1892 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
1893 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1894 if total_fee_msat > max_total_routing_fee_msat {
1895 if should_log_candidate {
1896 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
1898 num_ignored_total_fee_limit += 1;
1900 let channel_usage = ChannelUsage {
1901 amount_msat: amount_to_transfer_over_msat,
1902 inflight_htlc_msat: used_liquidity_msat,
1905 let channel_penalty_msat = scid_opt.map_or(0,
1906 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1907 channel_usage, score_params));
1908 let path_penalty_msat = $next_hops_path_penalty_msat
1909 .saturating_add(channel_penalty_msat);
1910 let new_graph_node = RouteGraphNode {
1911 node_id: $src_node_id,
1912 lowest_fee_to_node: total_fee_msat,
1913 total_cltv_delta: hop_total_cltv_delta,
1914 value_contribution_msat,
1915 path_htlc_minimum_msat,
1917 path_length_to_node,
1920 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1921 // if this way is cheaper than the already known
1922 // (considering the cost to "reach" this channel from the route destination,
1923 // the cost of using this channel,
1924 // and the cost of routing to the source node of this channel).
1925 // Also, consider that htlc_minimum_msat_difference, because we might end up
1926 // paying it. Consider the following exploit:
1927 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1928 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1929 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1930 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1932 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1933 // but it may require additional tracking - we don't want to double-count
1934 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1935 // can't use something that may decrease on future hops.
1936 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1937 .saturating_add(old_entry.path_penalty_msat);
1938 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1939 .saturating_add(path_penalty_msat);
1941 if !old_entry.was_processed && new_cost < old_cost {
1942 targets.push(new_graph_node);
1943 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1944 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1945 old_entry.total_fee_msat = total_fee_msat;
1946 old_entry.node_id = $dest_node_id.clone();
1947 old_entry.candidate = $candidate.clone();
1948 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1949 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1950 old_entry.path_penalty_msat = path_penalty_msat;
1951 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1953 old_entry.value_contribution_msat = value_contribution_msat;
1955 hop_contribution_amt_msat = Some(value_contribution_msat);
1956 } else if old_entry.was_processed && new_cost < old_cost {
1957 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1959 // If we're skipping processing a node which was previously
1960 // processed even though we found another path to it with a
1961 // cheaper fee, check that it was because the second path we
1962 // found (which we are processing now) has a lower value
1963 // contribution due to an HTLC minimum limit.
1965 // e.g. take a graph with two paths from node 1 to node 2, one
1966 // through channel A, and one through channel B. Channel A and
1967 // B are both in the to-process heap, with their scores set by
1968 // a higher htlc_minimum than fee.
1969 // Channel A is processed first, and the channels onwards from
1970 // node 1 are added to the to-process heap. Thereafter, we pop
1971 // Channel B off of the heap, note that it has a much more
1972 // restrictive htlc_maximum_msat, and recalculate the fees for
1973 // all of node 1's channels using the new, reduced, amount.
1975 // This would be bogus - we'd be selecting a higher-fee path
1976 // with a lower htlc_maximum_msat instead of the one we'd
1977 // already decided to use.
1978 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1980 value_contribution_msat + path_penalty_msat <
1981 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1988 if should_log_candidate {
1990 "Ignoring {} due to its htlc_minimum_msat limit.",
1991 LoggedCandidateHop(&$candidate));
1993 num_ignored_htlc_minimum_msat_limit += 1;
1997 hop_contribution_amt_msat
2001 let default_node_features = default_node_features();
2003 // Find ways (channels with destination) to reach a given node and store them
2004 // in the corresponding data structures (routing graph etc).
2005 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2006 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2007 // This data can later be helpful to optimize routing (pay lower fees).
2008 macro_rules! add_entries_to_cheapest_to_target_node {
2009 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
2010 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
2011 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2012 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2013 let was_processed = elem.was_processed;
2014 elem.was_processed = true;
2017 // Entries are added to dist in add_entry!() when there is a channel from a node.
2018 // Because there are no channels from payee, it will not have a dist entry at this point.
2019 // If we're processing any other node, it is always be the result of a channel from it.
2020 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2025 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2026 for details in first_channels {
2027 let candidate = CandidateRouteHop::FirstHop { details };
2028 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
2029 $next_hops_value_contribution,
2030 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
2031 $next_hops_cltv_delta, $next_hops_path_length);
2035 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2038 &default_node_features
2041 if !features.requires_unknown_bits() {
2042 for chan_id in $node.channels.iter() {
2043 let chan = network_channels.get(chan_id).unwrap();
2044 if !chan.features.requires_unknown_bits() {
2045 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2046 if first_hops.is_none() || *source != our_node_id {
2047 if directed_channel.direction().enabled {
2048 let candidate = CandidateRouteHop::PublicHop {
2049 info: directed_channel,
2050 short_channel_id: *chan_id,
2052 add_entry!(candidate, *source, $node_id,
2053 $fee_to_target_msat,
2054 $next_hops_value_contribution,
2055 $next_hops_path_htlc_minimum_msat,
2056 $next_hops_path_penalty_msat,
2057 $next_hops_cltv_delta, $next_hops_path_length);
2068 let mut payment_paths = Vec::<PaymentPath>::new();
2070 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2071 'paths_collection: loop {
2072 // For every new path, start from scratch, except for used_liquidities, which
2073 // helps to avoid reusing previously selected paths in future iterations.
2076 hit_minimum_limit = false;
2078 // If first hop is a private channel and the only way to reach the payee, this is the only
2079 // place where it could be added.
2080 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2081 for details in first_channels {
2082 let candidate = CandidateRouteHop::FirstHop { details };
2083 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
2084 0, 0u64, 0, 0).is_some();
2085 log_trace!(logger, "{} direct route to payee via {}",
2086 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2090 // Add the payee as a target, so that the payee-to-payer
2091 // search algorithm knows what to start with.
2092 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2093 // The payee is not in our network graph, so nothing to add here.
2094 // There is still a chance of reaching them via last_hops though,
2095 // so don't yet fail the payment here.
2096 // If not, targets.pop() will not even let us enter the loop in step 2.
2099 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2104 // If a caller provided us with last hops, add them to routing targets. Since this happens
2105 // earlier than general path finding, they will be somewhat prioritized, although currently
2106 // it matters only if the fees are exactly the same.
2107 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2108 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2109 let have_intro_node_in_graph =
2110 // Only add the hops in this route to our candidate set if either
2111 // we have a direct channel to the first hop or the first hop is
2112 // in the regular network graph.
2113 first_hop_targets.get(&intro_node_id).is_some() ||
2114 network_nodes.get(&intro_node_id).is_some();
2115 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2116 let candidate = if hint.1.blinded_hops.len() == 1 {
2117 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2118 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2119 let mut path_contribution_msat = path_value_msat;
2120 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2121 0, path_contribution_msat, 0, 0_u64, 0, 0)
2123 path_contribution_msat = hop_used_msat;
2125 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2126 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2128 for details in first_channels {
2129 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2130 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2134 let path_min = candidate.htlc_minimum_msat().saturating_add(
2135 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2136 add_entry!(first_hop_candidate, our_node_id, intro_node_id, blinded_path_fee,
2137 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2138 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2142 for route in payment_params.payee.unblinded_route_hints().iter()
2143 .filter(|route| !route.0.is_empty())
2145 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2146 let first_hop_src_is_reachable =
2147 // Only add the hops in this route to our candidate set if either we are part of
2148 // the first hop, we have a direct channel to the first hop, or the first hop is in
2149 // the regular network graph.
2150 our_node_id == first_hop_src_id ||
2151 first_hop_targets.get(&first_hop_src_id).is_some() ||
2152 network_nodes.get(&first_hop_src_id).is_some();
2153 if first_hop_src_is_reachable {
2154 // We start building the path from reverse, i.e., from payee
2155 // to the first RouteHintHop in the path.
2156 let hop_iter = route.0.iter().rev();
2157 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2158 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2159 let mut hop_used = true;
2160 let mut aggregate_next_hops_fee_msat: u64 = 0;
2161 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2162 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2163 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2164 let mut aggregate_next_hops_path_length: u8 = 0;
2165 let mut aggregate_path_contribution_msat = path_value_msat;
2167 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2168 let source = NodeId::from_pubkey(&hop.src_node_id);
2169 let target = NodeId::from_pubkey(&prev_hop_id);
2171 if let Some(first_channels) = first_hop_targets.get(&target) {
2172 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2173 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2174 hop.short_channel_id);
2179 let candidate = network_channels
2180 .get(&hop.short_channel_id)
2181 .and_then(|channel| channel.as_directed_to(&target))
2182 .map(|(info, _)| CandidateRouteHop::PublicHop {
2184 short_channel_id: hop.short_channel_id,
2186 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2188 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2189 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2190 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2191 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2193 aggregate_path_contribution_msat = hop_used_msat;
2195 // If this hop was not used then there is no use checking the preceding
2196 // hops in the RouteHint. We can break by just searching for a direct
2197 // channel between last checked hop and first_hop_targets.
2201 let used_liquidity_msat = used_liquidities
2202 .get(&candidate.id(source < target)).copied()
2204 let channel_usage = ChannelUsage {
2205 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2206 inflight_htlc_msat: used_liquidity_msat,
2207 effective_capacity: candidate.effective_capacity(),
2209 let channel_penalty_msat = scorer.channel_penalty_msat(
2210 hop.short_channel_id, &source, &target, channel_usage, score_params
2212 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2213 .saturating_add(channel_penalty_msat);
2215 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2216 .saturating_add(hop.cltv_expiry_delta as u32);
2218 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2221 // Searching for a direct channel between last checked hop and first_hop_targets
2222 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2223 sort_first_hop_channels(first_channels, &used_liquidities,
2224 recommended_value_msat, our_node_pubkey);
2225 for details in first_channels {
2226 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2227 add_entry!(first_hop_candidate, our_node_id, target,
2228 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2229 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2230 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2238 // In the next values of the iterator, the aggregate fees already reflects
2239 // the sum of value sent from payer (final_value_msat) and routing fees
2240 // for the last node in the RouteHint. We need to just add the fees to
2241 // route through the current node so that the preceding node (next iteration)
2243 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2244 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2245 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2247 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2248 // this route hint's source node to forward said min over this channel.
2249 aggregate_next_hops_path_htlc_minimum_msat = {
2250 let curr_htlc_min = cmp::max(
2251 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2253 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2254 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2257 if idx == route.0.len() - 1 {
2258 // The last hop in this iterator is the first hop in
2259 // overall RouteHint.
2260 // If this hop connects to a node with which we have a direct channel,
2261 // ignore the network graph and, if the last hop was added, add our
2262 // direct channel to the candidate set.
2264 // Note that we *must* check if the last hop was added as `add_entry`
2265 // always assumes that the third argument is a node to which we have a
2267 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2268 sort_first_hop_channels(first_channels, &used_liquidities,
2269 recommended_value_msat, our_node_pubkey);
2270 for details in first_channels {
2271 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2272 add_entry!(first_hop_candidate, our_node_id,
2273 NodeId::from_pubkey(&hop.src_node_id),
2274 aggregate_next_hops_fee_msat,
2275 aggregate_path_contribution_msat,
2276 aggregate_next_hops_path_htlc_minimum_msat,
2277 aggregate_next_hops_path_penalty_msat,
2278 aggregate_next_hops_cltv_delta,
2279 aggregate_next_hops_path_length);
2287 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2289 // At this point, targets are filled with the data from first and
2290 // last hops communicated by the caller, and the payment receiver.
2291 let mut found_new_path = false;
2294 // If this loop terminates due the exhaustion of targets, two situations are possible:
2295 // - not enough outgoing liquidity:
2296 // 0 < already_collected_value_msat < final_value_msat
2297 // - enough outgoing liquidity:
2298 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2299 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2300 // paths_collection will be stopped because found_new_path==false.
2301 // This is not necessarily a routing failure.
2302 '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() {
2304 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2305 // traversing the graph and arrange the path out of what we found.
2306 if node_id == our_node_id {
2307 let mut new_entry = dist.remove(&our_node_id).unwrap();
2308 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2311 let mut features_set = false;
2312 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2313 for details in first_channels {
2314 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2315 if details.get_outbound_payment_scid().unwrap() == scid {
2316 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2317 features_set = true;
2324 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2325 if let Some(node_info) = node.announcement_info.as_ref() {
2326 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2328 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2331 // We can fill in features for everything except hops which were
2332 // provided via the invoice we're paying. We could guess based on the
2333 // recipient's features but for now we simply avoid guessing at all.
2337 // Means we succesfully traversed from the payer to the payee, now
2338 // save this path for the payment route. Also, update the liquidity
2339 // remaining on the used hops, so that we take them into account
2340 // while looking for more paths.
2341 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2345 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2346 Some(payment_hop) => payment_hop,
2347 // We can't arrive at None because, if we ever add an entry to targets,
2348 // we also fill in the entry in dist (see add_entry!).
2349 None => unreachable!(),
2351 // We "propagate" the fees one hop backward (topologically) here,
2352 // so that fees paid for a HTLC forwarding on the current channel are
2353 // associated with the previous channel (where they will be subtracted).
2354 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2355 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2357 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2358 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2360 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2361 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2363 let mut payment_path = PaymentPath {hops: ordered_hops};
2365 // We could have possibly constructed a slightly inconsistent path: since we reduce
2366 // value being transferred along the way, we could have violated htlc_minimum_msat
2367 // on some channels we already passed (assuming dest->source direction). Here, we
2368 // recompute the fees again, so that if that's the case, we match the currently
2369 // underpaid htlc_minimum_msat with fees.
2370 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2371 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2372 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2374 // Since a path allows to transfer as much value as
2375 // the smallest channel it has ("bottleneck"), we should recompute
2376 // the fees so sender HTLC don't overpay fees when traversing
2377 // larger channels than the bottleneck. This may happen because
2378 // when we were selecting those channels we were not aware how much value
2379 // this path will transfer, and the relative fee for them
2380 // might have been computed considering a larger value.
2381 // Remember that we used these channels so that we don't rely
2382 // on the same liquidity in future paths.
2383 let mut prevented_redundant_path_selection = false;
2384 let prev_hop_iter = core::iter::once(&our_node_id)
2385 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2386 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2387 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2388 let used_liquidity_msat = used_liquidities
2389 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2390 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2391 .or_insert(spent_on_hop_msat);
2392 let hop_capacity = hop.candidate.effective_capacity();
2393 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2394 if *used_liquidity_msat == hop_max_msat {
2395 // If this path used all of this channel's available liquidity, we know
2396 // this path will not be selected again in the next loop iteration.
2397 prevented_redundant_path_selection = true;
2399 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2401 if !prevented_redundant_path_selection {
2402 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2403 // we'll probably end up picking the same path again on the next iteration.
2404 // Decrease the available liquidity of a hop in the middle of the path.
2405 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2406 let exhausted = u64::max_value();
2408 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2409 LoggedCandidateHop(victim_candidate));
2410 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2411 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2414 // Track the total amount all our collected paths allow to send so that we know
2415 // when to stop looking for more paths
2416 already_collected_value_msat += value_contribution_msat;
2418 payment_paths.push(payment_path);
2419 found_new_path = true;
2420 break 'path_construction;
2423 // If we found a path back to the payee, we shouldn't try to process it again. This is
2424 // the equivalent of the `elem.was_processed` check in
2425 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2426 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2428 // Otherwise, since the current target node is not us,
2429 // keep "unrolling" the payment graph from payee to payer by
2430 // finding a way to reach the current target from the payer side.
2431 match network_nodes.get(&node_id) {
2434 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2435 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2436 total_cltv_delta, path_length_to_node);
2442 if !found_new_path && channel_saturation_pow_half != 0 {
2443 channel_saturation_pow_half = 0;
2444 continue 'paths_collection;
2446 // If we don't support MPP, no use trying to gather more value ever.
2447 break 'paths_collection;
2451 // Stop either when the recommended value is reached or if no new path was found in this
2453 // In the latter case, making another path finding attempt won't help,
2454 // because we deterministically terminated the search due to low liquidity.
2455 if !found_new_path && channel_saturation_pow_half != 0 {
2456 channel_saturation_pow_half = 0;
2457 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2458 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2459 path_value_msat = recommended_value_msat;
2460 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2461 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2462 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2463 break 'paths_collection;
2464 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2465 // Further, if this was our first walk of the graph, and we weren't limited by an
2466 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2467 // limited by an htlc_minimum_msat value, find another path with a higher value,
2468 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2469 // still keeping a lower total fee than this path.
2470 if !hit_minimum_limit {
2471 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2472 break 'paths_collection;
2474 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher value to meet htlc_minimum_msat limit.");
2475 path_value_msat = recommended_value_msat;
2479 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2480 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2481 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2482 num_ignored_total_fee_limit;
2483 if num_ignored_total > 0 {
2485 "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure, {} due to htlc_minimum_msat limit, {} to avoid overpaying, {} due to maximum total fee limit. Total: {} ignored candidates.",
2486 num_ignored_value_contribution, num_ignored_path_length_limit,
2487 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2488 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2489 num_ignored_total_fee_limit, num_ignored_total);
2493 if payment_paths.len() == 0 {
2494 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2497 if already_collected_value_msat < final_value_msat {
2498 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2502 let mut selected_route = payment_paths;
2504 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2505 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2507 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2508 // the value they contribute towards the payment amount.
2509 // We sort in descending order as we will remove from the front in `retain`, next.
2510 selected_route.sort_unstable_by(|a, b|
2511 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2512 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2515 // We should make sure that at least 1 path left.
2516 let mut paths_left = selected_route.len();
2517 selected_route.retain(|path| {
2518 if paths_left == 1 {
2521 let path_value_msat = path.get_value_msat();
2522 if path_value_msat <= overpaid_value_msat {
2523 overpaid_value_msat -= path_value_msat;
2529 debug_assert!(selected_route.len() > 0);
2531 if overpaid_value_msat != 0 {
2533 // Now, subtract the remaining overpaid value from the most-expensive path.
2534 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2535 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2536 selected_route.sort_unstable_by(|a, b| {
2537 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2538 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2539 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2541 let expensive_payment_path = selected_route.first_mut().unwrap();
2543 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2544 // can't go negative.
2545 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2546 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2550 // Sort by the path itself and combine redundant paths.
2551 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2552 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2554 selected_route.sort_unstable_by_key(|path| {
2555 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2556 debug_assert!(path.hops.len() <= key.len());
2557 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2562 for idx in 0..(selected_route.len() - 1) {
2563 if idx + 1 >= selected_route.len() { break; }
2564 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2565 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2566 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2567 selected_route[idx].update_value_and_recompute_fees(new_value);
2568 selected_route.remove(idx + 1);
2572 let mut paths = Vec::new();
2573 for payment_path in selected_route {
2574 let mut hops = Vec::with_capacity(payment_path.hops.len());
2575 let mut prev_hop_node_id = our_node_id;
2576 for (hop, node_features) in payment_path.hops.iter()
2577 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2579 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2580 // If we sourced the hop from the graph we're sure the target node is announced.
2582 } else if let CandidateRouteHop::FirstHop { details } = hop.candidate {
2583 // If this is a first hop we also know if it's announced.
2586 // If we sourced it any other way, we double-check the network graph to see if
2587 // there are announced channels between the endpoints. If so, the hop might be
2588 // referring to any of the announced channels, as its `short_channel_id` might be
2589 // an alias, in which case we don't take any chances here.
2590 network_graph.node(&hop.node_id).map_or(false, |hop_node|
2591 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2592 .map_or(false, |c| c.as_directed_from(&prev_hop_node_id).is_some()))
2596 hops.push(RouteHop {
2597 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)})?,
2598 node_features: node_features.clone(),
2599 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2600 channel_features: hop.candidate.features(),
2601 fee_msat: hop.fee_msat,
2602 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2603 maybe_announced_channel,
2606 prev_hop_node_id = hop.node_id;
2608 let mut final_cltv_delta = final_cltv_expiry_delta;
2609 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2610 if let Some(blinded_path) = h.candidate.blinded_path() {
2611 final_cltv_delta = h.candidate.cltv_expiry_delta();
2613 hops: blinded_path.blinded_hops.clone(),
2614 blinding_point: blinded_path.blinding_point,
2615 excess_final_cltv_expiry_delta: 0,
2616 final_value_msat: h.fee_msat,
2620 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2621 // applicable for the previous hop.
2622 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2623 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2626 paths.push(Path { hops, blinded_tail });
2628 // Make sure we would never create a route with more paths than we allow.
2629 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2631 if let Some(node_features) = payment_params.payee.node_features() {
2632 for path in paths.iter_mut() {
2633 path.hops.last_mut().unwrap().node_features = node_features.clone();
2637 let route = Route { paths, route_params: Some(route_params.clone()) };
2639 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2640 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2641 if route.get_total_fees() > max_total_routing_fee_msat {
2642 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2643 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2647 log_info!(logger, "Got route: {}", log_route!(route));
2651 // When an adversarial intermediary node observes a payment, it may be able to infer its
2652 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2653 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2654 // payment path by adding a randomized 'shadow route' offset to the final hop.
2655 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2656 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2658 let network_channels = network_graph.channels();
2659 let network_nodes = network_graph.nodes();
2661 for path in route.paths.iter_mut() {
2662 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2664 // Remember the last three nodes of the random walk and avoid looping back on them.
2665 // Init with the last three nodes from the actual path, if possible.
2666 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2667 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2668 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2670 // Choose the last publicly known node as the starting point for the random walk.
2671 let mut cur_hop: Option<NodeId> = None;
2672 let mut path_nonce = [0u8; 12];
2673 if let Some(starting_hop) = path.hops.iter().rev()
2674 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2675 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2676 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2679 // Init PRNG with the path-dependant nonce, which is static for private paths.
2680 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2681 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2683 // Pick a random path length in [1 .. 3]
2684 prng.process_in_place(&mut random_path_bytes);
2685 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2687 for random_hop in 0..random_walk_length {
2688 // If we don't find a suitable offset in the public network graph, we default to
2689 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2690 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2692 if let Some(cur_node_id) = cur_hop {
2693 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2694 // Randomly choose the next unvisited hop.
2695 prng.process_in_place(&mut random_path_bytes);
2696 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2697 .checked_rem(cur_node.channels.len())
2698 .and_then(|index| cur_node.channels.get(index))
2699 .and_then(|id| network_channels.get(id)) {
2700 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2701 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2702 nodes_to_avoid[random_hop] = *next_id;
2703 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2704 cur_hop = Some(*next_id);
2711 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2712 .checked_add(random_hop_offset)
2713 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2716 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2717 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2718 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2720 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2721 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2722 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2723 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2724 max_path_offset = cmp::max(
2725 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2726 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2727 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2729 // Add 'shadow' CLTV offset to the final hop
2730 if let Some(tail) = path.blinded_tail.as_mut() {
2731 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2732 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2734 if let Some(last_hop) = path.hops.last_mut() {
2735 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2736 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2741 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2742 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2744 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2745 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2746 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2747 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2748 ) -> Result<Route, LightningError>
2749 where L::Target: Logger, GL::Target: Logger {
2750 let graph_lock = network_graph.read_only();
2751 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2752 &graph_lock, logger, random_seed_bytes)?;
2753 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2757 fn build_route_from_hops_internal<L: Deref>(
2758 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2759 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2760 ) -> Result<Route, LightningError> where L::Target: Logger {
2763 our_node_id: NodeId,
2764 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2767 impl ScoreLookUp for HopScorer {
2768 type ScoreParams = ();
2769 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2770 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2772 let mut cur_id = self.our_node_id;
2773 for i in 0..self.hop_ids.len() {
2774 if let Some(next_id) = self.hop_ids[i] {
2775 if cur_id == *source && next_id == *target {
2787 impl<'a> Writeable for HopScorer {
2789 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2794 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2795 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2798 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2799 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2800 for i in 0..hops.len() {
2801 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2804 let scorer = HopScorer { our_node_id, hop_ids };
2806 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
2811 use crate::blinded_path::{BlindedHop, BlindedPath};
2812 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2813 use crate::routing::utxo::UtxoResult;
2814 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2815 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2816 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2817 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2818 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2819 use crate::chain::transaction::OutPoint;
2820 use crate::sign::EntropySource;
2821 use crate::ln::ChannelId;
2822 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2823 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2824 use crate::ln::channelmanager;
2825 use crate::offers::invoice::BlindedPayInfo;
2826 use crate::util::config::UserConfig;
2827 use crate::util::test_utils as ln_test_utils;
2828 use crate::util::chacha20::ChaCha20;
2829 use crate::util::ser::{Readable, Writeable};
2831 use crate::util::ser::Writer;
2833 use bitcoin::hashes::Hash;
2834 use bitcoin::network::constants::Network;
2835 use bitcoin::blockdata::constants::genesis_block;
2836 use bitcoin::blockdata::script::Builder;
2837 use bitcoin::blockdata::opcodes;
2838 use bitcoin::blockdata::transaction::TxOut;
2842 use bitcoin::secp256k1::{PublicKey,SecretKey};
2843 use bitcoin::secp256k1::Secp256k1;
2845 use crate::io::Cursor;
2846 use crate::prelude::*;
2847 use crate::sync::Arc;
2849 use core::convert::TryInto;
2851 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2852 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2853 channelmanager::ChannelDetails {
2854 channel_id: ChannelId::new_zero(),
2855 counterparty: channelmanager::ChannelCounterparty {
2858 unspendable_punishment_reserve: 0,
2859 forwarding_info: None,
2860 outbound_htlc_minimum_msat: None,
2861 outbound_htlc_maximum_msat: None,
2863 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2866 outbound_scid_alias: None,
2867 inbound_scid_alias: None,
2868 channel_value_satoshis: 0,
2870 outbound_capacity_msat,
2871 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2872 next_outbound_htlc_minimum_msat: 0,
2873 inbound_capacity_msat: 42,
2874 unspendable_punishment_reserve: None,
2875 confirmations_required: None,
2876 confirmations: None,
2877 force_close_spend_delay: None,
2878 is_outbound: true, is_channel_ready: true,
2879 is_usable: true, is_public: true,
2880 inbound_htlc_minimum_msat: None,
2881 inbound_htlc_maximum_msat: None,
2883 feerate_sat_per_1000_weight: None,
2884 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2889 fn simple_route_test() {
2890 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2891 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2892 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2893 let scorer = ln_test_utils::TestScorer::new();
2894 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2895 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2897 // Simple route to 2 via 1
2899 let route_params = RouteParameters::from_payment_params_and_value(
2900 payment_params.clone(), 0);
2901 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2902 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
2903 &Default::default(), &random_seed_bytes) {
2904 assert_eq!(err, "Cannot send a payment of 0 msat");
2905 } else { panic!(); }
2907 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2908 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2909 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2910 assert_eq!(route.paths[0].hops.len(), 2);
2912 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2913 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2914 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2915 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2916 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2917 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2919 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2920 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2921 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2922 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2923 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2924 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2928 fn invalid_first_hop_test() {
2929 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2930 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2931 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2932 let scorer = ln_test_utils::TestScorer::new();
2933 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2934 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2936 // Simple route to 2 via 1
2938 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2940 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2941 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2942 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2943 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
2944 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2945 } else { panic!(); }
2947 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2948 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2949 assert_eq!(route.paths[0].hops.len(), 2);
2953 fn htlc_minimum_test() {
2954 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2955 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2956 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2957 let scorer = ln_test_utils::TestScorer::new();
2958 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2959 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2961 // Simple route to 2 via 1
2963 // Disable other paths
2964 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2965 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2966 short_channel_id: 12,
2968 flags: 2, // to disable
2969 cltv_expiry_delta: 0,
2970 htlc_minimum_msat: 0,
2971 htlc_maximum_msat: MAX_VALUE_MSAT,
2973 fee_proportional_millionths: 0,
2974 excess_data: Vec::new()
2976 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2977 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2978 short_channel_id: 3,
2980 flags: 2, // to disable
2981 cltv_expiry_delta: 0,
2982 htlc_minimum_msat: 0,
2983 htlc_maximum_msat: MAX_VALUE_MSAT,
2985 fee_proportional_millionths: 0,
2986 excess_data: Vec::new()
2988 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2989 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2990 short_channel_id: 13,
2992 flags: 2, // to disable
2993 cltv_expiry_delta: 0,
2994 htlc_minimum_msat: 0,
2995 htlc_maximum_msat: MAX_VALUE_MSAT,
2997 fee_proportional_millionths: 0,
2998 excess_data: Vec::new()
3000 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3001 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3002 short_channel_id: 6,
3004 flags: 2, // to disable
3005 cltv_expiry_delta: 0,
3006 htlc_minimum_msat: 0,
3007 htlc_maximum_msat: MAX_VALUE_MSAT,
3009 fee_proportional_millionths: 0,
3010 excess_data: Vec::new()
3012 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3013 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3014 short_channel_id: 7,
3016 flags: 2, // to disable
3017 cltv_expiry_delta: 0,
3018 htlc_minimum_msat: 0,
3019 htlc_maximum_msat: MAX_VALUE_MSAT,
3021 fee_proportional_millionths: 0,
3022 excess_data: Vec::new()
3025 // Check against amount_to_transfer_over_msat.
3026 // Set minimal HTLC of 200_000_000 msat.
3027 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3028 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3029 short_channel_id: 2,
3032 cltv_expiry_delta: 0,
3033 htlc_minimum_msat: 200_000_000,
3034 htlc_maximum_msat: MAX_VALUE_MSAT,
3036 fee_proportional_millionths: 0,
3037 excess_data: Vec::new()
3040 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3042 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3043 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3044 short_channel_id: 4,
3047 cltv_expiry_delta: 0,
3048 htlc_minimum_msat: 0,
3049 htlc_maximum_msat: 199_999_999,
3051 fee_proportional_millionths: 0,
3052 excess_data: Vec::new()
3055 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3056 let route_params = RouteParameters::from_payment_params_and_value(
3057 payment_params, 199_999_999);
3058 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3059 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3060 &Default::default(), &random_seed_bytes) {
3061 assert_eq!(err, "Failed to find a path to the given destination");
3062 } else { panic!(); }
3064 // Lift the restriction on the first hop.
3065 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3066 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3067 short_channel_id: 2,
3070 cltv_expiry_delta: 0,
3071 htlc_minimum_msat: 0,
3072 htlc_maximum_msat: MAX_VALUE_MSAT,
3074 fee_proportional_millionths: 0,
3075 excess_data: Vec::new()
3078 // A payment above the minimum should pass
3079 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3080 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3081 assert_eq!(route.paths[0].hops.len(), 2);
3085 fn htlc_minimum_overpay_test() {
3086 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3087 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3088 let config = UserConfig::default();
3089 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3090 let scorer = ln_test_utils::TestScorer::new();
3091 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3092 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3094 // A route to node#2 via two paths.
3095 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3096 // Thus, they can't send 60 without overpaying.
3097 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3098 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3099 short_channel_id: 2,
3102 cltv_expiry_delta: 0,
3103 htlc_minimum_msat: 35_000,
3104 htlc_maximum_msat: 40_000,
3106 fee_proportional_millionths: 0,
3107 excess_data: Vec::new()
3109 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3110 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3111 short_channel_id: 12,
3114 cltv_expiry_delta: 0,
3115 htlc_minimum_msat: 35_000,
3116 htlc_maximum_msat: 40_000,
3118 fee_proportional_millionths: 0,
3119 excess_data: Vec::new()
3123 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3124 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3125 short_channel_id: 13,
3128 cltv_expiry_delta: 0,
3129 htlc_minimum_msat: 0,
3130 htlc_maximum_msat: MAX_VALUE_MSAT,
3132 fee_proportional_millionths: 0,
3133 excess_data: Vec::new()
3135 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3136 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3137 short_channel_id: 4,
3140 cltv_expiry_delta: 0,
3141 htlc_minimum_msat: 0,
3142 htlc_maximum_msat: MAX_VALUE_MSAT,
3144 fee_proportional_millionths: 0,
3145 excess_data: Vec::new()
3148 // Disable other paths
3149 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3150 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3151 short_channel_id: 1,
3153 flags: 2, // to disable
3154 cltv_expiry_delta: 0,
3155 htlc_minimum_msat: 0,
3156 htlc_maximum_msat: MAX_VALUE_MSAT,
3158 fee_proportional_millionths: 0,
3159 excess_data: Vec::new()
3162 let mut route_params = RouteParameters::from_payment_params_and_value(
3163 payment_params.clone(), 60_000);
3164 route_params.max_total_routing_fee_msat = Some(15_000);
3165 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3166 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3167 // Overpay fees to hit htlc_minimum_msat.
3168 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3169 // TODO: this could be better balanced to overpay 10k and not 15k.
3170 assert_eq!(overpaid_fees, 15_000);
3172 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3173 // while taking even more fee to match htlc_minimum_msat.
3174 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3175 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3176 short_channel_id: 12,
3179 cltv_expiry_delta: 0,
3180 htlc_minimum_msat: 65_000,
3181 htlc_maximum_msat: 80_000,
3183 fee_proportional_millionths: 0,
3184 excess_data: Vec::new()
3186 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3187 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3188 short_channel_id: 2,
3191 cltv_expiry_delta: 0,
3192 htlc_minimum_msat: 0,
3193 htlc_maximum_msat: MAX_VALUE_MSAT,
3195 fee_proportional_millionths: 0,
3196 excess_data: Vec::new()
3198 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3199 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3200 short_channel_id: 4,
3203 cltv_expiry_delta: 0,
3204 htlc_minimum_msat: 0,
3205 htlc_maximum_msat: MAX_VALUE_MSAT,
3207 fee_proportional_millionths: 100_000,
3208 excess_data: Vec::new()
3211 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3212 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3213 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3214 assert_eq!(route.paths.len(), 1);
3215 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3216 let fees = route.paths[0].hops[0].fee_msat;
3217 assert_eq!(fees, 5_000);
3219 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3220 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3221 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3222 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3223 // the other channel.
3224 assert_eq!(route.paths.len(), 1);
3225 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3226 let fees = route.paths[0].hops[0].fee_msat;
3227 assert_eq!(fees, 5_000);
3231 fn htlc_minimum_recipient_overpay_test() {
3232 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3233 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3234 let config = UserConfig::default();
3235 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3236 let scorer = ln_test_utils::TestScorer::new();
3237 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3238 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3240 // Route to node2 over a single path which requires overpaying the recipient themselves.
3242 // First disable all paths except the us -> node1 -> node2 path
3243 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3244 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3245 short_channel_id: 13,
3248 cltv_expiry_delta: 0,
3249 htlc_minimum_msat: 0,
3250 htlc_maximum_msat: 0,
3252 fee_proportional_millionths: 0,
3253 excess_data: Vec::new()
3256 // Set channel 4 to free but with a high htlc_minimum_msat
3257 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3258 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3259 short_channel_id: 4,
3262 cltv_expiry_delta: 0,
3263 htlc_minimum_msat: 15_000,
3264 htlc_maximum_msat: MAX_VALUE_MSAT,
3266 fee_proportional_millionths: 0,
3267 excess_data: Vec::new()
3270 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3271 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3272 // what we try to find a route for, so this test only just happens to work out to exactly
3274 let mut route_params = RouteParameters::from_payment_params_and_value(
3275 payment_params.clone(), 5_000);
3276 route_params.max_total_routing_fee_msat = Some(9_999);
3277 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3278 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3279 &Default::default(), &random_seed_bytes) {
3280 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3281 } else { panic!(); }
3283 let mut route_params = RouteParameters::from_payment_params_and_value(
3284 payment_params.clone(), 5_000);
3285 route_params.max_total_routing_fee_msat = Some(10_000);
3286 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3287 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3288 assert_eq!(route.get_total_fees(), 10_000);
3292 fn disable_channels_test() {
3293 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3294 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3295 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3296 let scorer = ln_test_utils::TestScorer::new();
3297 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3298 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3300 // // Disable channels 4 and 12 by flags=2
3301 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3303 short_channel_id: 4,
3305 flags: 2, // to disable
3306 cltv_expiry_delta: 0,
3307 htlc_minimum_msat: 0,
3308 htlc_maximum_msat: MAX_VALUE_MSAT,
3310 fee_proportional_millionths: 0,
3311 excess_data: Vec::new()
3313 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3314 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3315 short_channel_id: 12,
3317 flags: 2, // to disable
3318 cltv_expiry_delta: 0,
3319 htlc_minimum_msat: 0,
3320 htlc_maximum_msat: MAX_VALUE_MSAT,
3322 fee_proportional_millionths: 0,
3323 excess_data: Vec::new()
3326 // If all the channels require some features we don't understand, route should fail
3327 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3328 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3329 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3330 &Default::default(), &random_seed_bytes) {
3331 assert_eq!(err, "Failed to find a path to the given destination");
3332 } else { panic!(); }
3334 // If we specify a channel to node7, that overrides our local channel view and that gets used
3335 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3336 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3337 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3338 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3339 &Default::default(), &random_seed_bytes).unwrap();
3340 assert_eq!(route.paths[0].hops.len(), 2);
3342 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3343 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3344 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3345 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3346 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3347 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3349 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3350 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3351 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3352 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3353 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3354 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3358 fn disable_node_test() {
3359 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3360 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3361 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3362 let scorer = ln_test_utils::TestScorer::new();
3363 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3364 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3366 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3367 let mut unknown_features = NodeFeatures::empty();
3368 unknown_features.set_unknown_feature_required();
3369 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3370 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3371 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3373 // If all nodes require some features we don't understand, route should fail
3374 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3375 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3376 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3377 &Default::default(), &random_seed_bytes) {
3378 assert_eq!(err, "Failed to find a path to the given destination");
3379 } else { panic!(); }
3381 // If we specify a channel to node7, that overrides our local channel view and that gets used
3382 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3383 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3384 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3385 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3386 &Default::default(), &random_seed_bytes).unwrap();
3387 assert_eq!(route.paths[0].hops.len(), 2);
3389 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3390 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3391 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3392 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3393 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3394 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3396 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3397 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3398 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3399 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3400 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3401 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3403 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3404 // naively) assume that the user checked the feature bits on the invoice, which override
3405 // the node_announcement.
3409 fn our_chans_test() {
3410 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3411 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3412 let scorer = ln_test_utils::TestScorer::new();
3413 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3414 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3416 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3417 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3418 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3419 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3420 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3421 assert_eq!(route.paths[0].hops.len(), 3);
3423 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3424 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3425 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3426 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3427 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3428 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3430 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3431 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3432 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3433 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3434 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3435 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3437 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3438 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3439 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3440 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3441 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3442 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3444 // If we specify a channel to node7, that overrides our local channel view and that gets used
3445 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3446 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3447 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3448 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3449 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3450 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3451 &Default::default(), &random_seed_bytes).unwrap();
3452 assert_eq!(route.paths[0].hops.len(), 2);
3454 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3455 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3456 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3457 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3458 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3459 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3461 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3462 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3463 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3464 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3465 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3466 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3469 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3470 let zero_fees = RoutingFees {
3472 proportional_millionths: 0,
3474 vec![RouteHint(vec![RouteHintHop {
3475 src_node_id: nodes[3],
3476 short_channel_id: 8,
3478 cltv_expiry_delta: (8 << 4) | 1,
3479 htlc_minimum_msat: None,
3480 htlc_maximum_msat: None,
3482 ]), RouteHint(vec![RouteHintHop {
3483 src_node_id: nodes[4],
3484 short_channel_id: 9,
3487 proportional_millionths: 0,
3489 cltv_expiry_delta: (9 << 4) | 1,
3490 htlc_minimum_msat: None,
3491 htlc_maximum_msat: None,
3492 }]), RouteHint(vec![RouteHintHop {
3493 src_node_id: nodes[5],
3494 short_channel_id: 10,
3496 cltv_expiry_delta: (10 << 4) | 1,
3497 htlc_minimum_msat: None,
3498 htlc_maximum_msat: None,
3502 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3503 let zero_fees = RoutingFees {
3505 proportional_millionths: 0,
3507 vec![RouteHint(vec![RouteHintHop {
3508 src_node_id: nodes[2],
3509 short_channel_id: 5,
3512 proportional_millionths: 0,
3514 cltv_expiry_delta: (5 << 4) | 1,
3515 htlc_minimum_msat: None,
3516 htlc_maximum_msat: None,
3518 src_node_id: nodes[3],
3519 short_channel_id: 8,
3521 cltv_expiry_delta: (8 << 4) | 1,
3522 htlc_minimum_msat: None,
3523 htlc_maximum_msat: None,
3525 ]), RouteHint(vec![RouteHintHop {
3526 src_node_id: nodes[4],
3527 short_channel_id: 9,
3530 proportional_millionths: 0,
3532 cltv_expiry_delta: (9 << 4) | 1,
3533 htlc_minimum_msat: None,
3534 htlc_maximum_msat: None,
3535 }]), RouteHint(vec![RouteHintHop {
3536 src_node_id: nodes[5],
3537 short_channel_id: 10,
3539 cltv_expiry_delta: (10 << 4) | 1,
3540 htlc_minimum_msat: None,
3541 htlc_maximum_msat: None,
3546 fn partial_route_hint_test() {
3547 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3548 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3549 let scorer = ln_test_utils::TestScorer::new();
3550 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3551 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3553 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3554 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3555 // RouteHint may be partially used by the algo to build the best path.
3557 // First check that last hop can't have its source as the payee.
3558 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3559 src_node_id: nodes[6],
3560 short_channel_id: 8,
3563 proportional_millionths: 0,
3565 cltv_expiry_delta: (8 << 4) | 1,
3566 htlc_minimum_msat: None,
3567 htlc_maximum_msat: None,
3570 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3571 invalid_last_hops.push(invalid_last_hop);
3573 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3574 .with_route_hints(invalid_last_hops).unwrap();
3575 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3576 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3577 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3578 &Default::default(), &random_seed_bytes) {
3579 assert_eq!(err, "Route hint cannot have the payee as the source.");
3580 } else { panic!(); }
3583 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3584 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3585 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3586 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3587 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3588 assert_eq!(route.paths[0].hops.len(), 5);
3590 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3591 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3592 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3593 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3594 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3595 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3597 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3598 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3599 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3600 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3601 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3602 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3604 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3605 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3606 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3607 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3608 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3609 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3611 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3612 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3613 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3614 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3615 // If we have a peer in the node map, we'll use their features here since we don't have
3616 // a way of figuring out their features from the invoice:
3617 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3618 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3620 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3621 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3622 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3623 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3624 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3625 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3628 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3629 let zero_fees = RoutingFees {
3631 proportional_millionths: 0,
3633 vec![RouteHint(vec![RouteHintHop {
3634 src_node_id: nodes[3],
3635 short_channel_id: 8,
3637 cltv_expiry_delta: (8 << 4) | 1,
3638 htlc_minimum_msat: None,
3639 htlc_maximum_msat: None,
3640 }]), RouteHint(vec![
3642 ]), RouteHint(vec![RouteHintHop {
3643 src_node_id: nodes[5],
3644 short_channel_id: 10,
3646 cltv_expiry_delta: (10 << 4) | 1,
3647 htlc_minimum_msat: None,
3648 htlc_maximum_msat: None,
3653 fn ignores_empty_last_hops_test() {
3654 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3655 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3656 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3657 let scorer = ln_test_utils::TestScorer::new();
3658 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3659 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3661 // Test handling of an empty RouteHint passed in Invoice.
3662 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3663 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3664 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3665 assert_eq!(route.paths[0].hops.len(), 5);
3667 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3668 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3669 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3670 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3671 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3672 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3674 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3675 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3676 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3677 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3678 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3679 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3681 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3682 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3683 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3684 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3685 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3686 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3688 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3689 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3690 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3691 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3692 // If we have a peer in the node map, we'll use their features here since we don't have
3693 // a way of figuring out their features from the invoice:
3694 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3695 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3697 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3698 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3699 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3700 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3701 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3702 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3705 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3707 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3708 let zero_fees = RoutingFees {
3710 proportional_millionths: 0,
3712 vec![RouteHint(vec![RouteHintHop {
3713 src_node_id: hint_hops[0],
3714 short_channel_id: 0xff00,
3717 proportional_millionths: 0,
3719 cltv_expiry_delta: (5 << 4) | 1,
3720 htlc_minimum_msat: None,
3721 htlc_maximum_msat: None,
3723 src_node_id: hint_hops[1],
3724 short_channel_id: 0xff01,
3726 cltv_expiry_delta: (8 << 4) | 1,
3727 htlc_minimum_msat: None,
3728 htlc_maximum_msat: None,
3733 fn multi_hint_last_hops_test() {
3734 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3735 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3736 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3737 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3738 let scorer = ln_test_utils::TestScorer::new();
3739 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3740 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3741 // Test through channels 2, 3, 0xff00, 0xff01.
3742 // Test shows that multiple hop hints are considered.
3744 // Disabling channels 6 & 7 by flags=2
3745 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3746 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3747 short_channel_id: 6,
3749 flags: 2, // to disable
3750 cltv_expiry_delta: 0,
3751 htlc_minimum_msat: 0,
3752 htlc_maximum_msat: MAX_VALUE_MSAT,
3754 fee_proportional_millionths: 0,
3755 excess_data: Vec::new()
3757 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3758 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3759 short_channel_id: 7,
3761 flags: 2, // to disable
3762 cltv_expiry_delta: 0,
3763 htlc_minimum_msat: 0,
3764 htlc_maximum_msat: MAX_VALUE_MSAT,
3766 fee_proportional_millionths: 0,
3767 excess_data: Vec::new()
3770 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3771 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3772 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3773 assert_eq!(route.paths[0].hops.len(), 4);
3775 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3776 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3777 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3778 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3779 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3780 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3782 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3783 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3784 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3785 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3786 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3787 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3789 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3790 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3791 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3792 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3793 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3794 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3796 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3797 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3798 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3799 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3800 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3801 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3805 fn private_multi_hint_last_hops_test() {
3806 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3807 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3809 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3810 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3812 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3813 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3814 let scorer = ln_test_utils::TestScorer::new();
3815 // Test through channels 2, 3, 0xff00, 0xff01.
3816 // Test shows that multiple hop hints are considered.
3818 // Disabling channels 6 & 7 by flags=2
3819 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3820 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3821 short_channel_id: 6,
3823 flags: 2, // to disable
3824 cltv_expiry_delta: 0,
3825 htlc_minimum_msat: 0,
3826 htlc_maximum_msat: MAX_VALUE_MSAT,
3828 fee_proportional_millionths: 0,
3829 excess_data: Vec::new()
3831 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3832 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3833 short_channel_id: 7,
3835 flags: 2, // to disable
3836 cltv_expiry_delta: 0,
3837 htlc_minimum_msat: 0,
3838 htlc_maximum_msat: MAX_VALUE_MSAT,
3840 fee_proportional_millionths: 0,
3841 excess_data: Vec::new()
3844 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3845 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3846 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
3847 assert_eq!(route.paths[0].hops.len(), 4);
3849 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3850 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3851 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3852 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3853 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3854 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3856 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3857 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3858 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3859 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3860 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3861 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3863 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3864 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3865 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3866 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3867 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3868 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3870 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3871 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3872 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3873 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3874 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3875 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3878 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3879 let zero_fees = RoutingFees {
3881 proportional_millionths: 0,
3883 vec![RouteHint(vec![RouteHintHop {
3884 src_node_id: nodes[4],
3885 short_channel_id: 11,
3887 cltv_expiry_delta: (11 << 4) | 1,
3888 htlc_minimum_msat: None,
3889 htlc_maximum_msat: None,
3891 src_node_id: nodes[3],
3892 short_channel_id: 8,
3894 cltv_expiry_delta: (8 << 4) | 1,
3895 htlc_minimum_msat: None,
3896 htlc_maximum_msat: None,
3897 }]), RouteHint(vec![RouteHintHop {
3898 src_node_id: nodes[4],
3899 short_channel_id: 9,
3902 proportional_millionths: 0,
3904 cltv_expiry_delta: (9 << 4) | 1,
3905 htlc_minimum_msat: None,
3906 htlc_maximum_msat: None,
3907 }]), RouteHint(vec![RouteHintHop {
3908 src_node_id: nodes[5],
3909 short_channel_id: 10,
3911 cltv_expiry_delta: (10 << 4) | 1,
3912 htlc_minimum_msat: None,
3913 htlc_maximum_msat: None,
3918 fn last_hops_with_public_channel_test() {
3919 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3920 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3921 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3922 let scorer = ln_test_utils::TestScorer::new();
3923 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3924 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3925 // This test shows that public routes can be present in the invoice
3926 // which would be handled in the same manner.
3928 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3929 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3930 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3931 assert_eq!(route.paths[0].hops.len(), 5);
3933 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3934 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3935 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3936 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3937 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3938 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3940 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3941 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3942 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3943 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3944 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3945 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3947 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3948 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3949 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3950 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3951 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3952 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3954 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3955 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3956 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3957 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3958 // If we have a peer in the node map, we'll use their features here since we don't have
3959 // a way of figuring out their features from the invoice:
3960 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3961 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3963 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3964 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3965 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3966 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3967 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3968 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3972 fn our_chans_last_hop_connect_test() {
3973 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3974 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3975 let scorer = ln_test_utils::TestScorer::new();
3976 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3977 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3979 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3980 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3981 let mut last_hops = last_hops(&nodes);
3982 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3983 .with_route_hints(last_hops.clone()).unwrap();
3984 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3985 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3986 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3987 &Default::default(), &random_seed_bytes).unwrap();
3988 assert_eq!(route.paths[0].hops.len(), 2);
3990 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3991 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3992 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3993 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3994 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3995 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3997 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3998 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3999 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4000 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4001 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4002 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4004 last_hops[0].0[0].fees.base_msat = 1000;
4006 // Revert to via 6 as the fee on 8 goes up
4007 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4008 .with_route_hints(last_hops).unwrap();
4009 let route_params = RouteParameters::from_payment_params_and_value(
4010 payment_params.clone(), 100);
4011 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4012 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4013 assert_eq!(route.paths[0].hops.len(), 4);
4015 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4016 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4017 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4018 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4019 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4020 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4022 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4023 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4024 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4025 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4026 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4027 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4029 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4030 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4031 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4032 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4033 // If we have a peer in the node map, we'll use their features here since we don't have
4034 // a way of figuring out their features from the invoice:
4035 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4036 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4038 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4039 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4040 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4041 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4042 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4043 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4045 // ...but still use 8 for larger payments as 6 has a variable feerate
4046 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4047 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4048 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4049 assert_eq!(route.paths[0].hops.len(), 5);
4051 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4052 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4053 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4054 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4055 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4056 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4058 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4059 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4060 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4061 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4062 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4063 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4065 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4066 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4067 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4068 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4069 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4070 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4072 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4073 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4074 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4075 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4076 // If we have a peer in the node map, we'll use their features here since we don't have
4077 // a way of figuring out their features from the invoice:
4078 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4079 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4081 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4082 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4083 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4084 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4085 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4086 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4089 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> {
4090 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4091 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4092 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4094 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4095 let last_hops = RouteHint(vec![RouteHintHop {
4096 src_node_id: middle_node_id,
4097 short_channel_id: 8,
4100 proportional_millionths: last_hop_fee_prop,
4102 cltv_expiry_delta: (8 << 4) | 1,
4103 htlc_minimum_msat: None,
4104 htlc_maximum_msat: last_hop_htlc_max,
4106 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4107 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4108 let scorer = ln_test_utils::TestScorer::new();
4109 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4110 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4111 let logger = ln_test_utils::TestLogger::new();
4112 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4113 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4114 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4115 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4116 &random_seed_bytes);
4121 fn unannounced_path_test() {
4122 // We should be able to send a payment to a destination without any help of a routing graph
4123 // if we have a channel with a common counterparty that appears in the first and last hop
4125 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4127 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4128 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4129 assert_eq!(route.paths[0].hops.len(), 2);
4131 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4132 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4133 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4134 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4135 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4136 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4138 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4139 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4140 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4141 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4142 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4143 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4147 fn overflow_unannounced_path_test_liquidity_underflow() {
4148 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4149 // the last-hop had a fee which overflowed a u64, we'd panic.
4150 // This was due to us adding the first-hop from us unconditionally, causing us to think
4151 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4152 // In this test, we previously hit a subtraction underflow due to having less available
4153 // liquidity at the last hop than 0.
4154 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());
4158 fn overflow_unannounced_path_test_feerate_overflow() {
4159 // This tests for the same case as above, except instead of hitting a subtraction
4160 // underflow, we hit a case where the fee charged at a hop overflowed.
4161 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());
4165 fn available_amount_while_routing_test() {
4166 // Tests whether we choose the correct available channel amount while routing.
4168 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4169 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4170 let scorer = ln_test_utils::TestScorer::new();
4171 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4172 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4173 let config = UserConfig::default();
4174 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4176 // We will use a simple single-path route from
4177 // our node to node2 via node0: channels {1, 3}.
4179 // First disable all other paths.
4180 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4181 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4182 short_channel_id: 2,
4185 cltv_expiry_delta: 0,
4186 htlc_minimum_msat: 0,
4187 htlc_maximum_msat: 100_000,
4189 fee_proportional_millionths: 0,
4190 excess_data: Vec::new()
4192 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4193 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4194 short_channel_id: 12,
4197 cltv_expiry_delta: 0,
4198 htlc_minimum_msat: 0,
4199 htlc_maximum_msat: 100_000,
4201 fee_proportional_millionths: 0,
4202 excess_data: Vec::new()
4205 // Make the first channel (#1) very permissive,
4206 // and we will be testing all limits on the second channel.
4207 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4208 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4209 short_channel_id: 1,
4212 cltv_expiry_delta: 0,
4213 htlc_minimum_msat: 0,
4214 htlc_maximum_msat: 1_000_000_000,
4216 fee_proportional_millionths: 0,
4217 excess_data: Vec::new()
4220 // First, let's see if routing works if we have absolutely no idea about the available amount.
4221 // In this case, it should be set to 250_000 sats.
4222 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4223 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4224 short_channel_id: 3,
4227 cltv_expiry_delta: 0,
4228 htlc_minimum_msat: 0,
4229 htlc_maximum_msat: 250_000_000,
4231 fee_proportional_millionths: 0,
4232 excess_data: Vec::new()
4236 // Attempt to route more than available results in a failure.
4237 let route_params = RouteParameters::from_payment_params_and_value(
4238 payment_params.clone(), 250_000_001);
4239 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4240 &our_id, &route_params, &network_graph.read_only(), None,
4241 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4242 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4243 } else { panic!(); }
4247 // Now, attempt to route an exact amount we have should be fine.
4248 let route_params = RouteParameters::from_payment_params_and_value(
4249 payment_params.clone(), 250_000_000);
4250 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4251 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4252 assert_eq!(route.paths.len(), 1);
4253 let path = route.paths.last().unwrap();
4254 assert_eq!(path.hops.len(), 2);
4255 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4256 assert_eq!(path.final_value_msat(), 250_000_000);
4259 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4260 // Disable channel #1 and use another first hop.
4261 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4262 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4263 short_channel_id: 1,
4266 cltv_expiry_delta: 0,
4267 htlc_minimum_msat: 0,
4268 htlc_maximum_msat: 1_000_000_000,
4270 fee_proportional_millionths: 0,
4271 excess_data: Vec::new()
4274 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4275 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4278 // Attempt to route more than available results in a failure.
4279 let route_params = RouteParameters::from_payment_params_and_value(
4280 payment_params.clone(), 200_000_001);
4281 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4282 &our_id, &route_params, &network_graph.read_only(),
4283 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4284 &Default::default(), &random_seed_bytes) {
4285 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4286 } else { panic!(); }
4290 // Now, attempt to route an exact amount we have should be fine.
4291 let route_params = RouteParameters::from_payment_params_and_value(
4292 payment_params.clone(), 200_000_000);
4293 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4294 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4295 &Default::default(), &random_seed_bytes).unwrap();
4296 assert_eq!(route.paths.len(), 1);
4297 let path = route.paths.last().unwrap();
4298 assert_eq!(path.hops.len(), 2);
4299 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4300 assert_eq!(path.final_value_msat(), 200_000_000);
4303 // Enable channel #1 back.
4304 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4306 short_channel_id: 1,
4309 cltv_expiry_delta: 0,
4310 htlc_minimum_msat: 0,
4311 htlc_maximum_msat: 1_000_000_000,
4313 fee_proportional_millionths: 0,
4314 excess_data: Vec::new()
4318 // Now let's see if routing works if we know only htlc_maximum_msat.
4319 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4320 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4321 short_channel_id: 3,
4324 cltv_expiry_delta: 0,
4325 htlc_minimum_msat: 0,
4326 htlc_maximum_msat: 15_000,
4328 fee_proportional_millionths: 0,
4329 excess_data: Vec::new()
4333 // Attempt to route more than available results in a failure.
4334 let route_params = RouteParameters::from_payment_params_and_value(
4335 payment_params.clone(), 15_001);
4336 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4337 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4338 &scorer, &Default::default(), &random_seed_bytes) {
4339 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4340 } else { panic!(); }
4344 // Now, attempt to route an exact amount we have should be fine.
4345 let route_params = RouteParameters::from_payment_params_and_value(
4346 payment_params.clone(), 15_000);
4347 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4348 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4349 assert_eq!(route.paths.len(), 1);
4350 let path = route.paths.last().unwrap();
4351 assert_eq!(path.hops.len(), 2);
4352 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4353 assert_eq!(path.final_value_msat(), 15_000);
4356 // Now let's see if routing works if we know only capacity from the UTXO.
4358 // We can't change UTXO capacity on the fly, so we'll disable
4359 // the existing channel and add another one with the capacity we need.
4360 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4361 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4362 short_channel_id: 3,
4365 cltv_expiry_delta: 0,
4366 htlc_minimum_msat: 0,
4367 htlc_maximum_msat: MAX_VALUE_MSAT,
4369 fee_proportional_millionths: 0,
4370 excess_data: Vec::new()
4373 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4374 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4375 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4376 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4377 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4379 *chain_monitor.utxo_ret.lock().unwrap() =
4380 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4381 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4383 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4384 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4385 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4386 short_channel_id: 333,
4389 cltv_expiry_delta: (3 << 4) | 1,
4390 htlc_minimum_msat: 0,
4391 htlc_maximum_msat: 15_000,
4393 fee_proportional_millionths: 0,
4394 excess_data: Vec::new()
4396 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4397 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4398 short_channel_id: 333,
4401 cltv_expiry_delta: (3 << 4) | 2,
4402 htlc_minimum_msat: 0,
4403 htlc_maximum_msat: 15_000,
4405 fee_proportional_millionths: 0,
4406 excess_data: Vec::new()
4410 // Attempt to route more than available results in a failure.
4411 let route_params = RouteParameters::from_payment_params_and_value(
4412 payment_params.clone(), 15_001);
4413 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4414 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4415 &scorer, &Default::default(), &random_seed_bytes) {
4416 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4417 } else { panic!(); }
4421 // Now, attempt to route an exact amount we have should be fine.
4422 let route_params = RouteParameters::from_payment_params_and_value(
4423 payment_params.clone(), 15_000);
4424 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4425 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4426 assert_eq!(route.paths.len(), 1);
4427 let path = route.paths.last().unwrap();
4428 assert_eq!(path.hops.len(), 2);
4429 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4430 assert_eq!(path.final_value_msat(), 15_000);
4433 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4434 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4435 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4436 short_channel_id: 333,
4439 cltv_expiry_delta: 0,
4440 htlc_minimum_msat: 0,
4441 htlc_maximum_msat: 10_000,
4443 fee_proportional_millionths: 0,
4444 excess_data: Vec::new()
4448 // Attempt to route more than available results in a failure.
4449 let route_params = RouteParameters::from_payment_params_and_value(
4450 payment_params.clone(), 10_001);
4451 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4452 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4453 &scorer, &Default::default(), &random_seed_bytes) {
4454 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4455 } else { panic!(); }
4459 // Now, attempt to route an exact amount we have should be fine.
4460 let route_params = RouteParameters::from_payment_params_and_value(
4461 payment_params.clone(), 10_000);
4462 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4463 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4464 assert_eq!(route.paths.len(), 1);
4465 let path = route.paths.last().unwrap();
4466 assert_eq!(path.hops.len(), 2);
4467 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4468 assert_eq!(path.final_value_msat(), 10_000);
4473 fn available_liquidity_last_hop_test() {
4474 // Check that available liquidity properly limits the path even when only
4475 // one of the latter hops is limited.
4476 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4477 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4478 let scorer = ln_test_utils::TestScorer::new();
4479 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4480 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4481 let config = UserConfig::default();
4482 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4484 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4485 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4486 // Total capacity: 50 sats.
4488 // Disable other potential paths.
4489 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4490 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4491 short_channel_id: 2,
4494 cltv_expiry_delta: 0,
4495 htlc_minimum_msat: 0,
4496 htlc_maximum_msat: 100_000,
4498 fee_proportional_millionths: 0,
4499 excess_data: Vec::new()
4501 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4502 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4503 short_channel_id: 7,
4506 cltv_expiry_delta: 0,
4507 htlc_minimum_msat: 0,
4508 htlc_maximum_msat: 100_000,
4510 fee_proportional_millionths: 0,
4511 excess_data: Vec::new()
4516 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4517 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4518 short_channel_id: 12,
4521 cltv_expiry_delta: 0,
4522 htlc_minimum_msat: 0,
4523 htlc_maximum_msat: 100_000,
4525 fee_proportional_millionths: 0,
4526 excess_data: Vec::new()
4528 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4530 short_channel_id: 13,
4533 cltv_expiry_delta: 0,
4534 htlc_minimum_msat: 0,
4535 htlc_maximum_msat: 100_000,
4537 fee_proportional_millionths: 0,
4538 excess_data: Vec::new()
4541 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4542 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4543 short_channel_id: 6,
4546 cltv_expiry_delta: 0,
4547 htlc_minimum_msat: 0,
4548 htlc_maximum_msat: 50_000,
4550 fee_proportional_millionths: 0,
4551 excess_data: Vec::new()
4553 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4554 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4555 short_channel_id: 11,
4558 cltv_expiry_delta: 0,
4559 htlc_minimum_msat: 0,
4560 htlc_maximum_msat: 100_000,
4562 fee_proportional_millionths: 0,
4563 excess_data: Vec::new()
4566 // Attempt to route more than available results in a failure.
4567 let route_params = RouteParameters::from_payment_params_and_value(
4568 payment_params.clone(), 60_000);
4569 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4570 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4571 &scorer, &Default::default(), &random_seed_bytes) {
4572 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4573 } else { panic!(); }
4577 // Now, attempt to route 49 sats (just a bit below the capacity).
4578 let route_params = RouteParameters::from_payment_params_and_value(
4579 payment_params.clone(), 49_000);
4580 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4581 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4582 assert_eq!(route.paths.len(), 1);
4583 let mut total_amount_paid_msat = 0;
4584 for path in &route.paths {
4585 assert_eq!(path.hops.len(), 4);
4586 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4587 total_amount_paid_msat += path.final_value_msat();
4589 assert_eq!(total_amount_paid_msat, 49_000);
4593 // Attempt to route an exact amount is also fine
4594 let route_params = RouteParameters::from_payment_params_and_value(
4595 payment_params, 50_000);
4596 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4597 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4598 assert_eq!(route.paths.len(), 1);
4599 let mut total_amount_paid_msat = 0;
4600 for path in &route.paths {
4601 assert_eq!(path.hops.len(), 4);
4602 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4603 total_amount_paid_msat += path.final_value_msat();
4605 assert_eq!(total_amount_paid_msat, 50_000);
4610 fn ignore_fee_first_hop_test() {
4611 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4612 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4613 let scorer = ln_test_utils::TestScorer::new();
4614 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4615 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4616 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4618 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4619 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4620 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4621 short_channel_id: 1,
4624 cltv_expiry_delta: 0,
4625 htlc_minimum_msat: 0,
4626 htlc_maximum_msat: 100_000,
4627 fee_base_msat: 1_000_000,
4628 fee_proportional_millionths: 0,
4629 excess_data: Vec::new()
4631 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4632 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4633 short_channel_id: 3,
4636 cltv_expiry_delta: 0,
4637 htlc_minimum_msat: 0,
4638 htlc_maximum_msat: 50_000,
4640 fee_proportional_millionths: 0,
4641 excess_data: Vec::new()
4645 let route_params = RouteParameters::from_payment_params_and_value(
4646 payment_params, 50_000);
4647 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4648 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4649 assert_eq!(route.paths.len(), 1);
4650 let mut total_amount_paid_msat = 0;
4651 for path in &route.paths {
4652 assert_eq!(path.hops.len(), 2);
4653 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4654 total_amount_paid_msat += path.final_value_msat();
4656 assert_eq!(total_amount_paid_msat, 50_000);
4661 fn simple_mpp_route_test() {
4662 let (secp_ctx, _, _, _, _) = build_graph();
4663 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4664 let config = UserConfig::default();
4665 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4666 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4667 do_simple_mpp_route_test(clear_payment_params);
4669 // MPP to a 1-hop blinded path for nodes[2]
4670 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4671 let blinded_path = BlindedPath {
4672 introduction_node_id: nodes[2],
4673 blinding_point: ln_test_utils::pubkey(42),
4674 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4676 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4678 fee_proportional_millionths: 0,
4679 htlc_minimum_msat: 0,
4680 htlc_maximum_msat: 0,
4681 cltv_expiry_delta: 0,
4682 features: BlindedHopFeatures::empty(),
4684 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4685 .with_bolt12_features(bolt12_features.clone()).unwrap();
4686 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4688 // MPP to 3 2-hop blinded paths
4689 let mut blinded_path_node_0 = blinded_path.clone();
4690 blinded_path_node_0.introduction_node_id = nodes[0];
4691 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4692 let mut node_0_payinfo = blinded_payinfo.clone();
4693 node_0_payinfo.htlc_maximum_msat = 50_000;
4695 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4696 blinded_path_node_7.introduction_node_id = nodes[7];
4697 let mut node_7_payinfo = blinded_payinfo.clone();
4698 node_7_payinfo.htlc_maximum_msat = 60_000;
4700 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4701 blinded_path_node_1.introduction_node_id = nodes[1];
4702 let mut node_1_payinfo = blinded_payinfo.clone();
4703 node_1_payinfo.htlc_maximum_msat = 180_000;
4705 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4707 (node_0_payinfo, blinded_path_node_0),
4708 (node_7_payinfo, blinded_path_node_7),
4709 (node_1_payinfo, blinded_path_node_1)
4711 .with_bolt12_features(bolt12_features).unwrap();
4712 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4716 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4717 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4718 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4719 let scorer = ln_test_utils::TestScorer::new();
4720 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4721 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4723 // We need a route consisting of 3 paths:
4724 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4725 // To achieve this, the amount being transferred should be around
4726 // the total capacity of these 3 paths.
4728 // First, we set limits on these (previously unlimited) channels.
4729 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4731 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4732 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4733 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4734 short_channel_id: 1,
4737 cltv_expiry_delta: 0,
4738 htlc_minimum_msat: 0,
4739 htlc_maximum_msat: 100_000,
4741 fee_proportional_millionths: 0,
4742 excess_data: Vec::new()
4744 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4745 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4746 short_channel_id: 3,
4749 cltv_expiry_delta: 0,
4750 htlc_minimum_msat: 0,
4751 htlc_maximum_msat: 50_000,
4753 fee_proportional_millionths: 0,
4754 excess_data: Vec::new()
4757 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4758 // (total limit 60).
4759 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4760 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4761 short_channel_id: 12,
4764 cltv_expiry_delta: 0,
4765 htlc_minimum_msat: 0,
4766 htlc_maximum_msat: 60_000,
4768 fee_proportional_millionths: 0,
4769 excess_data: Vec::new()
4771 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4772 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4773 short_channel_id: 13,
4776 cltv_expiry_delta: 0,
4777 htlc_minimum_msat: 0,
4778 htlc_maximum_msat: 60_000,
4780 fee_proportional_millionths: 0,
4781 excess_data: Vec::new()
4784 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4785 // (total capacity 180 sats).
4786 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4787 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4788 short_channel_id: 2,
4791 cltv_expiry_delta: 0,
4792 htlc_minimum_msat: 0,
4793 htlc_maximum_msat: 200_000,
4795 fee_proportional_millionths: 0,
4796 excess_data: Vec::new()
4798 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4799 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4800 short_channel_id: 4,
4803 cltv_expiry_delta: 0,
4804 htlc_minimum_msat: 0,
4805 htlc_maximum_msat: 180_000,
4807 fee_proportional_millionths: 0,
4808 excess_data: Vec::new()
4812 // Attempt to route more than available results in a failure.
4813 let route_params = RouteParameters::from_payment_params_and_value(
4814 payment_params.clone(), 300_000);
4815 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4816 &our_id, &route_params, &network_graph.read_only(), None,
4817 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4818 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4819 } else { panic!(); }
4823 // Attempt to route while setting max_path_count to 0 results in a failure.
4824 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4825 let route_params = RouteParameters::from_payment_params_and_value(
4826 zero_payment_params, 100);
4827 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4828 &our_id, &route_params, &network_graph.read_only(), None,
4829 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4830 assert_eq!(err, "Can't find a route with no paths allowed.");
4831 } else { panic!(); }
4835 // Attempt to route while setting max_path_count to 3 results in a failure.
4836 // This is the case because the minimal_value_contribution_msat would require each path
4837 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4838 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4839 let route_params = RouteParameters::from_payment_params_and_value(
4840 fail_payment_params, 250_000);
4841 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4842 &our_id, &route_params, &network_graph.read_only(), None,
4843 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4844 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4845 } else { panic!(); }
4849 // Now, attempt to route 250 sats (just a bit below the capacity).
4850 // Our algorithm should provide us with these 3 paths.
4851 let route_params = RouteParameters::from_payment_params_and_value(
4852 payment_params.clone(), 250_000);
4853 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4854 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4855 assert_eq!(route.paths.len(), 3);
4856 let mut total_amount_paid_msat = 0;
4857 for path in &route.paths {
4858 if let Some(bt) = &path.blinded_tail {
4859 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4861 assert_eq!(path.hops.len(), 2);
4862 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4864 total_amount_paid_msat += path.final_value_msat();
4866 assert_eq!(total_amount_paid_msat, 250_000);
4870 // Attempt to route an exact amount is also fine
4871 let route_params = RouteParameters::from_payment_params_and_value(
4872 payment_params.clone(), 290_000);
4873 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4874 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4875 assert_eq!(route.paths.len(), 3);
4876 let mut total_amount_paid_msat = 0;
4877 for path in &route.paths {
4878 if payment_params.payee.blinded_route_hints().len() != 0 {
4879 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4880 if let Some(bt) = &path.blinded_tail {
4881 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4882 if bt.hops.len() > 1 {
4883 assert_eq!(path.hops.last().unwrap().pubkey,
4884 payment_params.payee.blinded_route_hints().iter()
4885 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4886 .map(|(_, p)| p.introduction_node_id).unwrap());
4888 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4891 assert_eq!(path.hops.len(), 2);
4892 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4894 total_amount_paid_msat += path.final_value_msat();
4896 assert_eq!(total_amount_paid_msat, 290_000);
4901 fn long_mpp_route_test() {
4902 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4903 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4904 let scorer = ln_test_utils::TestScorer::new();
4905 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4906 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4907 let config = UserConfig::default();
4908 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4909 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4911 // We need a route consisting of 3 paths:
4912 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4913 // Note that these paths overlap (channels 5, 12, 13).
4914 // We will route 300 sats.
4915 // Each path will have 100 sats capacity, those channels which
4916 // are used twice will have 200 sats capacity.
4918 // Disable other potential paths.
4919 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4920 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4921 short_channel_id: 2,
4924 cltv_expiry_delta: 0,
4925 htlc_minimum_msat: 0,
4926 htlc_maximum_msat: 100_000,
4928 fee_proportional_millionths: 0,
4929 excess_data: Vec::new()
4931 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4932 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4933 short_channel_id: 7,
4936 cltv_expiry_delta: 0,
4937 htlc_minimum_msat: 0,
4938 htlc_maximum_msat: 100_000,
4940 fee_proportional_millionths: 0,
4941 excess_data: Vec::new()
4944 // Path via {node0, node2} is channels {1, 3, 5}.
4945 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4946 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4947 short_channel_id: 1,
4950 cltv_expiry_delta: 0,
4951 htlc_minimum_msat: 0,
4952 htlc_maximum_msat: 100_000,
4954 fee_proportional_millionths: 0,
4955 excess_data: Vec::new()
4957 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4958 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4959 short_channel_id: 3,
4962 cltv_expiry_delta: 0,
4963 htlc_minimum_msat: 0,
4964 htlc_maximum_msat: 100_000,
4966 fee_proportional_millionths: 0,
4967 excess_data: Vec::new()
4970 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4971 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4972 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4974 short_channel_id: 5,
4977 cltv_expiry_delta: 0,
4978 htlc_minimum_msat: 0,
4979 htlc_maximum_msat: 200_000,
4981 fee_proportional_millionths: 0,
4982 excess_data: Vec::new()
4985 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4986 // Add 100 sats to the capacities of {12, 13}, because these channels
4987 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4988 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4989 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4990 short_channel_id: 12,
4993 cltv_expiry_delta: 0,
4994 htlc_minimum_msat: 0,
4995 htlc_maximum_msat: 200_000,
4997 fee_proportional_millionths: 0,
4998 excess_data: Vec::new()
5000 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5001 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5002 short_channel_id: 13,
5005 cltv_expiry_delta: 0,
5006 htlc_minimum_msat: 0,
5007 htlc_maximum_msat: 200_000,
5009 fee_proportional_millionths: 0,
5010 excess_data: Vec::new()
5013 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5014 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5015 short_channel_id: 6,
5018 cltv_expiry_delta: 0,
5019 htlc_minimum_msat: 0,
5020 htlc_maximum_msat: 100_000,
5022 fee_proportional_millionths: 0,
5023 excess_data: Vec::new()
5025 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5026 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5027 short_channel_id: 11,
5030 cltv_expiry_delta: 0,
5031 htlc_minimum_msat: 0,
5032 htlc_maximum_msat: 100_000,
5034 fee_proportional_millionths: 0,
5035 excess_data: Vec::new()
5038 // Path via {node7, node2} is channels {12, 13, 5}.
5039 // We already limited them to 200 sats (they are used twice for 100 sats).
5040 // Nothing to do here.
5043 // Attempt to route more than available results in a failure.
5044 let route_params = RouteParameters::from_payment_params_and_value(
5045 payment_params.clone(), 350_000);
5046 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5047 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5048 &scorer, &Default::default(), &random_seed_bytes) {
5049 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5050 } else { panic!(); }
5054 // Now, attempt to route 300 sats (exact amount we can route).
5055 // Our algorithm should provide us with these 3 paths, 100 sats each.
5056 let route_params = RouteParameters::from_payment_params_and_value(
5057 payment_params, 300_000);
5058 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5059 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5060 assert_eq!(route.paths.len(), 3);
5062 let mut total_amount_paid_msat = 0;
5063 for path in &route.paths {
5064 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5065 total_amount_paid_msat += path.final_value_msat();
5067 assert_eq!(total_amount_paid_msat, 300_000);
5073 fn mpp_cheaper_route_test() {
5074 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5075 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5076 let scorer = ln_test_utils::TestScorer::new();
5077 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5078 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5079 let config = UserConfig::default();
5080 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5082 // This test checks that if we have two cheaper paths and one more expensive path,
5083 // so that liquidity-wise any 2 of 3 combination is sufficient,
5084 // two cheaper paths will be taken.
5085 // These paths have equal available liquidity.
5087 // We need a combination of 3 paths:
5088 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5089 // Note that these paths overlap (channels 5, 12, 13).
5090 // Each path will have 100 sats capacity, those channels which
5091 // are used twice will have 200 sats capacity.
5093 // Disable other potential paths.
5094 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5095 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5096 short_channel_id: 2,
5099 cltv_expiry_delta: 0,
5100 htlc_minimum_msat: 0,
5101 htlc_maximum_msat: 100_000,
5103 fee_proportional_millionths: 0,
5104 excess_data: Vec::new()
5106 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5107 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5108 short_channel_id: 7,
5111 cltv_expiry_delta: 0,
5112 htlc_minimum_msat: 0,
5113 htlc_maximum_msat: 100_000,
5115 fee_proportional_millionths: 0,
5116 excess_data: Vec::new()
5119 // Path via {node0, node2} is channels {1, 3, 5}.
5120 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5121 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5122 short_channel_id: 1,
5125 cltv_expiry_delta: 0,
5126 htlc_minimum_msat: 0,
5127 htlc_maximum_msat: 100_000,
5129 fee_proportional_millionths: 0,
5130 excess_data: Vec::new()
5132 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5133 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5134 short_channel_id: 3,
5137 cltv_expiry_delta: 0,
5138 htlc_minimum_msat: 0,
5139 htlc_maximum_msat: 100_000,
5141 fee_proportional_millionths: 0,
5142 excess_data: Vec::new()
5145 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5146 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5147 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5148 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5149 short_channel_id: 5,
5152 cltv_expiry_delta: 0,
5153 htlc_minimum_msat: 0,
5154 htlc_maximum_msat: 200_000,
5156 fee_proportional_millionths: 0,
5157 excess_data: Vec::new()
5160 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5161 // Add 100 sats to the capacities of {12, 13}, because these channels
5162 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5163 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5164 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5165 short_channel_id: 12,
5168 cltv_expiry_delta: 0,
5169 htlc_minimum_msat: 0,
5170 htlc_maximum_msat: 200_000,
5172 fee_proportional_millionths: 0,
5173 excess_data: Vec::new()
5175 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5176 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5177 short_channel_id: 13,
5180 cltv_expiry_delta: 0,
5181 htlc_minimum_msat: 0,
5182 htlc_maximum_msat: 200_000,
5184 fee_proportional_millionths: 0,
5185 excess_data: Vec::new()
5188 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5189 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5190 short_channel_id: 6,
5193 cltv_expiry_delta: 0,
5194 htlc_minimum_msat: 0,
5195 htlc_maximum_msat: 100_000,
5196 fee_base_msat: 1_000,
5197 fee_proportional_millionths: 0,
5198 excess_data: Vec::new()
5200 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5201 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5202 short_channel_id: 11,
5205 cltv_expiry_delta: 0,
5206 htlc_minimum_msat: 0,
5207 htlc_maximum_msat: 100_000,
5209 fee_proportional_millionths: 0,
5210 excess_data: Vec::new()
5213 // Path via {node7, node2} is channels {12, 13, 5}.
5214 // We already limited them to 200 sats (they are used twice for 100 sats).
5215 // Nothing to do here.
5218 // Now, attempt to route 180 sats.
5219 // Our algorithm should provide us with these 2 paths.
5220 let route_params = RouteParameters::from_payment_params_and_value(
5221 payment_params, 180_000);
5222 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5223 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5224 assert_eq!(route.paths.len(), 2);
5226 let mut total_value_transferred_msat = 0;
5227 let mut total_paid_msat = 0;
5228 for path in &route.paths {
5229 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5230 total_value_transferred_msat += path.final_value_msat();
5231 for hop in &path.hops {
5232 total_paid_msat += hop.fee_msat;
5235 // If we paid fee, this would be higher.
5236 assert_eq!(total_value_transferred_msat, 180_000);
5237 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5238 assert_eq!(total_fees_paid, 0);
5243 fn fees_on_mpp_route_test() {
5244 // This test makes sure that MPP algorithm properly takes into account
5245 // fees charged on the channels, by making the fees impactful:
5246 // if the fee is not properly accounted for, the behavior is different.
5247 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5248 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5249 let scorer = ln_test_utils::TestScorer::new();
5250 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5251 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5252 let config = UserConfig::default();
5253 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5255 // We need a route consisting of 2 paths:
5256 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5257 // We will route 200 sats, Each path will have 100 sats capacity.
5259 // This test is not particularly stable: e.g.,
5260 // there's a way to route via {node0, node2, node4}.
5261 // It works while pathfinding is deterministic, but can be broken otherwise.
5262 // It's fine to ignore this concern for now.
5264 // Disable other potential paths.
5265 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5266 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5267 short_channel_id: 2,
5270 cltv_expiry_delta: 0,
5271 htlc_minimum_msat: 0,
5272 htlc_maximum_msat: 100_000,
5274 fee_proportional_millionths: 0,
5275 excess_data: Vec::new()
5278 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5279 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5280 short_channel_id: 7,
5283 cltv_expiry_delta: 0,
5284 htlc_minimum_msat: 0,
5285 htlc_maximum_msat: 100_000,
5287 fee_proportional_millionths: 0,
5288 excess_data: Vec::new()
5291 // Path via {node0, node2} is channels {1, 3, 5}.
5292 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5293 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5294 short_channel_id: 1,
5297 cltv_expiry_delta: 0,
5298 htlc_minimum_msat: 0,
5299 htlc_maximum_msat: 100_000,
5301 fee_proportional_millionths: 0,
5302 excess_data: Vec::new()
5304 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5306 short_channel_id: 3,
5309 cltv_expiry_delta: 0,
5310 htlc_minimum_msat: 0,
5311 htlc_maximum_msat: 100_000,
5313 fee_proportional_millionths: 0,
5314 excess_data: Vec::new()
5317 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5318 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5319 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5320 short_channel_id: 5,
5323 cltv_expiry_delta: 0,
5324 htlc_minimum_msat: 0,
5325 htlc_maximum_msat: 100_000,
5327 fee_proportional_millionths: 0,
5328 excess_data: Vec::new()
5331 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5332 // All channels should be 100 sats capacity. But for the fee experiment,
5333 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5334 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5335 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5336 // so no matter how large are other channels,
5337 // the whole path will be limited by 100 sats with just these 2 conditions:
5338 // - channel 12 capacity is 250 sats
5339 // - fee for channel 6 is 150 sats
5340 // Let's test this by enforcing these 2 conditions and removing other limits.
5341 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5342 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5343 short_channel_id: 12,
5346 cltv_expiry_delta: 0,
5347 htlc_minimum_msat: 0,
5348 htlc_maximum_msat: 250_000,
5350 fee_proportional_millionths: 0,
5351 excess_data: Vec::new()
5353 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5354 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5355 short_channel_id: 13,
5358 cltv_expiry_delta: 0,
5359 htlc_minimum_msat: 0,
5360 htlc_maximum_msat: MAX_VALUE_MSAT,
5362 fee_proportional_millionths: 0,
5363 excess_data: Vec::new()
5366 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5367 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5368 short_channel_id: 6,
5371 cltv_expiry_delta: 0,
5372 htlc_minimum_msat: 0,
5373 htlc_maximum_msat: MAX_VALUE_MSAT,
5374 fee_base_msat: 150_000,
5375 fee_proportional_millionths: 0,
5376 excess_data: Vec::new()
5378 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5379 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5380 short_channel_id: 11,
5383 cltv_expiry_delta: 0,
5384 htlc_minimum_msat: 0,
5385 htlc_maximum_msat: MAX_VALUE_MSAT,
5387 fee_proportional_millionths: 0,
5388 excess_data: Vec::new()
5392 // Attempt to route more than available results in a failure.
5393 let route_params = RouteParameters::from_payment_params_and_value(
5394 payment_params.clone(), 210_000);
5395 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5396 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5397 &scorer, &Default::default(), &random_seed_bytes) {
5398 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5399 } else { panic!(); }
5403 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5404 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5405 max_total_routing_fee_msat: Some(149_999) };
5406 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5407 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5408 &scorer, &(), &random_seed_bytes) {
5409 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5410 } else { panic!(); }
5414 // Now, attempt to route 200 sats (exact amount we can route).
5415 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5416 max_total_routing_fee_msat: Some(150_000) };
5417 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5418 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5419 assert_eq!(route.paths.len(), 2);
5421 let mut total_amount_paid_msat = 0;
5422 for path in &route.paths {
5423 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5424 total_amount_paid_msat += path.final_value_msat();
5426 assert_eq!(total_amount_paid_msat, 200_000);
5427 assert_eq!(route.get_total_fees(), 150_000);
5432 fn mpp_with_last_hops() {
5433 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5434 // via a single last-hop route hint, we'd fail to route if we first collected routes
5435 // totaling close but not quite enough to fund the full payment.
5437 // This was because we considered last-hop hints to have exactly the sought payment amount
5438 // instead of the amount we were trying to collect, needlessly limiting our path searching
5439 // at the very first hop.
5441 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5442 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5443 // to only have the remaining to-collect amount in available liquidity.
5445 // This bug appeared in production in some specific channel configurations.
5446 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5447 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5448 let scorer = ln_test_utils::TestScorer::new();
5449 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5450 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5451 let config = UserConfig::default();
5452 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5453 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5454 src_node_id: nodes[2],
5455 short_channel_id: 42,
5456 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5457 cltv_expiry_delta: 42,
5458 htlc_minimum_msat: None,
5459 htlc_maximum_msat: None,
5460 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5462 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5463 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5464 // would first use the no-fee route and then fail to find a path along the second route as
5465 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5466 // under 5% of our payment amount.
5467 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5468 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5469 short_channel_id: 1,
5472 cltv_expiry_delta: (5 << 4) | 5,
5473 htlc_minimum_msat: 0,
5474 htlc_maximum_msat: 99_000,
5475 fee_base_msat: u32::max_value(),
5476 fee_proportional_millionths: u32::max_value(),
5477 excess_data: Vec::new()
5479 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5480 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5481 short_channel_id: 2,
5484 cltv_expiry_delta: (5 << 4) | 3,
5485 htlc_minimum_msat: 0,
5486 htlc_maximum_msat: 99_000,
5487 fee_base_msat: u32::max_value(),
5488 fee_proportional_millionths: u32::max_value(),
5489 excess_data: Vec::new()
5491 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5492 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5493 short_channel_id: 4,
5496 cltv_expiry_delta: (4 << 4) | 1,
5497 htlc_minimum_msat: 0,
5498 htlc_maximum_msat: MAX_VALUE_MSAT,
5500 fee_proportional_millionths: 0,
5501 excess_data: Vec::new()
5503 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5504 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5505 short_channel_id: 13,
5507 flags: 0|2, // Channel disabled
5508 cltv_expiry_delta: (13 << 4) | 1,
5509 htlc_minimum_msat: 0,
5510 htlc_maximum_msat: MAX_VALUE_MSAT,
5512 fee_proportional_millionths: 2000000,
5513 excess_data: Vec::new()
5516 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5518 let route_params = RouteParameters::from_payment_params_and_value(
5519 payment_params, 100_000);
5520 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5521 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5522 assert_eq!(route.paths.len(), 2);
5523 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5524 // Paths are manually ordered ordered by SCID, so:
5525 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5526 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5527 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5528 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5529 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5530 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5531 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5532 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5533 assert_eq!(route.get_total_fees(), 1);
5534 assert_eq!(route.get_total_amount(), 100_000);
5538 fn drop_lowest_channel_mpp_route_test() {
5539 // This test checks that low-capacity channel is dropped when after
5540 // path finding we realize that we found more capacity than we need.
5541 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5542 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5543 let scorer = ln_test_utils::TestScorer::new();
5544 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5545 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5546 let config = UserConfig::default();
5547 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5548 .with_max_channel_saturation_power_of_half(0);
5550 // We need a route consisting of 3 paths:
5551 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5553 // The first and the second paths should be sufficient, but the third should be
5554 // cheaper, so that we select it but drop later.
5556 // First, we set limits on these (previously unlimited) channels.
5557 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5559 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5560 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5561 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5562 short_channel_id: 1,
5565 cltv_expiry_delta: 0,
5566 htlc_minimum_msat: 0,
5567 htlc_maximum_msat: 100_000,
5569 fee_proportional_millionths: 0,
5570 excess_data: Vec::new()
5572 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5573 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5574 short_channel_id: 3,
5577 cltv_expiry_delta: 0,
5578 htlc_minimum_msat: 0,
5579 htlc_maximum_msat: 50_000,
5581 fee_proportional_millionths: 0,
5582 excess_data: Vec::new()
5585 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5586 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5587 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5588 short_channel_id: 12,
5591 cltv_expiry_delta: 0,
5592 htlc_minimum_msat: 0,
5593 htlc_maximum_msat: 60_000,
5595 fee_proportional_millionths: 0,
5596 excess_data: Vec::new()
5598 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5599 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5600 short_channel_id: 13,
5603 cltv_expiry_delta: 0,
5604 htlc_minimum_msat: 0,
5605 htlc_maximum_msat: 60_000,
5607 fee_proportional_millionths: 0,
5608 excess_data: Vec::new()
5611 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5612 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5613 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5614 short_channel_id: 2,
5617 cltv_expiry_delta: 0,
5618 htlc_minimum_msat: 0,
5619 htlc_maximum_msat: 20_000,
5621 fee_proportional_millionths: 0,
5622 excess_data: Vec::new()
5624 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5625 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5626 short_channel_id: 4,
5629 cltv_expiry_delta: 0,
5630 htlc_minimum_msat: 0,
5631 htlc_maximum_msat: 20_000,
5633 fee_proportional_millionths: 0,
5634 excess_data: Vec::new()
5638 // Attempt to route more than available results in a failure.
5639 let route_params = RouteParameters::from_payment_params_and_value(
5640 payment_params.clone(), 150_000);
5641 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5642 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5643 &scorer, &Default::default(), &random_seed_bytes) {
5644 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5645 } else { panic!(); }
5649 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5650 // Our algorithm should provide us with these 3 paths.
5651 let route_params = RouteParameters::from_payment_params_and_value(
5652 payment_params.clone(), 125_000);
5653 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5654 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5655 assert_eq!(route.paths.len(), 3);
5656 let mut total_amount_paid_msat = 0;
5657 for path in &route.paths {
5658 assert_eq!(path.hops.len(), 2);
5659 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5660 total_amount_paid_msat += path.final_value_msat();
5662 assert_eq!(total_amount_paid_msat, 125_000);
5666 // Attempt to route without the last small cheap channel
5667 let route_params = RouteParameters::from_payment_params_and_value(
5668 payment_params, 90_000);
5669 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5670 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5671 assert_eq!(route.paths.len(), 2);
5672 let mut total_amount_paid_msat = 0;
5673 for path in &route.paths {
5674 assert_eq!(path.hops.len(), 2);
5675 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5676 total_amount_paid_msat += path.final_value_msat();
5678 assert_eq!(total_amount_paid_msat, 90_000);
5683 fn min_criteria_consistency() {
5684 // Test that we don't use an inconsistent metric between updating and walking nodes during
5685 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5686 // was updated with a different criterion from the heap sorting, resulting in loops in
5687 // calculated paths. We test for that specific case here.
5689 // We construct a network that looks like this:
5691 // node2 -1(3)2- node3
5695 // node1 -1(5)2- node4 -1(1)2- node6
5701 // We create a loop on the side of our real path - our destination is node 6, with a
5702 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5703 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5704 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5705 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5706 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5707 // "previous hop" being set to node 3, creating a loop in the path.
5708 let secp_ctx = Secp256k1::new();
5709 let logger = Arc::new(ln_test_utils::TestLogger::new());
5710 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5711 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5712 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5713 let scorer = ln_test_utils::TestScorer::new();
5714 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5715 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5716 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5718 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5719 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5720 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5721 short_channel_id: 6,
5724 cltv_expiry_delta: (6 << 4) | 0,
5725 htlc_minimum_msat: 0,
5726 htlc_maximum_msat: MAX_VALUE_MSAT,
5728 fee_proportional_millionths: 0,
5729 excess_data: Vec::new()
5731 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5733 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5734 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5735 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5736 short_channel_id: 5,
5739 cltv_expiry_delta: (5 << 4) | 0,
5740 htlc_minimum_msat: 0,
5741 htlc_maximum_msat: MAX_VALUE_MSAT,
5743 fee_proportional_millionths: 0,
5744 excess_data: Vec::new()
5746 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5748 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5749 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5750 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5751 short_channel_id: 4,
5754 cltv_expiry_delta: (4 << 4) | 0,
5755 htlc_minimum_msat: 0,
5756 htlc_maximum_msat: MAX_VALUE_MSAT,
5758 fee_proportional_millionths: 0,
5759 excess_data: Vec::new()
5761 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5763 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5764 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5765 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5766 short_channel_id: 3,
5769 cltv_expiry_delta: (3 << 4) | 0,
5770 htlc_minimum_msat: 0,
5771 htlc_maximum_msat: MAX_VALUE_MSAT,
5773 fee_proportional_millionths: 0,
5774 excess_data: Vec::new()
5776 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5778 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5779 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5780 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5781 short_channel_id: 2,
5784 cltv_expiry_delta: (2 << 4) | 0,
5785 htlc_minimum_msat: 0,
5786 htlc_maximum_msat: MAX_VALUE_MSAT,
5788 fee_proportional_millionths: 0,
5789 excess_data: Vec::new()
5792 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5793 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5794 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5795 short_channel_id: 1,
5798 cltv_expiry_delta: (1 << 4) | 0,
5799 htlc_minimum_msat: 100,
5800 htlc_maximum_msat: MAX_VALUE_MSAT,
5802 fee_proportional_millionths: 0,
5803 excess_data: Vec::new()
5805 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5808 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5809 let route_params = RouteParameters::from_payment_params_and_value(
5810 payment_params, 10_000);
5811 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5812 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5813 assert_eq!(route.paths.len(), 1);
5814 assert_eq!(route.paths[0].hops.len(), 3);
5816 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5817 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5818 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5819 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5820 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5821 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5823 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5824 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5825 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5826 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5827 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5828 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5830 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5831 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5832 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5833 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5834 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5835 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5841 fn exact_fee_liquidity_limit() {
5842 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5843 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5844 // we calculated fees on a higher value, resulting in us ignoring such paths.
5845 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5846 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5847 let scorer = ln_test_utils::TestScorer::new();
5848 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5849 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5850 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5852 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5854 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5855 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5856 short_channel_id: 2,
5859 cltv_expiry_delta: 0,
5860 htlc_minimum_msat: 0,
5861 htlc_maximum_msat: 85_000,
5863 fee_proportional_millionths: 0,
5864 excess_data: Vec::new()
5867 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5868 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5869 short_channel_id: 12,
5872 cltv_expiry_delta: (4 << 4) | 1,
5873 htlc_minimum_msat: 0,
5874 htlc_maximum_msat: 270_000,
5876 fee_proportional_millionths: 1000000,
5877 excess_data: Vec::new()
5881 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5882 // 200% fee charged channel 13 in the 1-to-2 direction.
5883 let mut route_params = RouteParameters::from_payment_params_and_value(
5884 payment_params, 90_000);
5885 route_params.max_total_routing_fee_msat = Some(90_000*2);
5886 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5887 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5888 assert_eq!(route.paths.len(), 1);
5889 assert_eq!(route.paths[0].hops.len(), 2);
5891 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5892 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5893 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5894 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5895 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5896 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5898 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5899 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5900 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5901 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5902 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5903 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5908 fn htlc_max_reduction_below_min() {
5909 // Test that if, while walking the graph, we reduce the value being sent to meet an
5910 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5911 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5912 // resulting in us thinking there is no possible path, even if other paths exist.
5913 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5914 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5915 let scorer = ln_test_utils::TestScorer::new();
5916 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5917 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5918 let config = UserConfig::default();
5919 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5921 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5922 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5923 // then try to send 90_000.
5924 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5925 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5926 short_channel_id: 2,
5929 cltv_expiry_delta: 0,
5930 htlc_minimum_msat: 0,
5931 htlc_maximum_msat: 80_000,
5933 fee_proportional_millionths: 0,
5934 excess_data: Vec::new()
5936 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5937 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5938 short_channel_id: 4,
5941 cltv_expiry_delta: (4 << 4) | 1,
5942 htlc_minimum_msat: 90_000,
5943 htlc_maximum_msat: MAX_VALUE_MSAT,
5945 fee_proportional_millionths: 0,
5946 excess_data: Vec::new()
5950 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5951 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5952 // expensive) channels 12-13 path.
5953 let mut route_params = RouteParameters::from_payment_params_and_value(
5954 payment_params, 90_000);
5955 route_params.max_total_routing_fee_msat = Some(90_000*2);
5956 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5957 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5958 assert_eq!(route.paths.len(), 1);
5959 assert_eq!(route.paths[0].hops.len(), 2);
5961 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5962 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5963 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5964 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5965 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5966 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5968 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5969 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5970 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5971 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5972 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5973 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5978 fn multiple_direct_first_hops() {
5979 // Previously we'd only ever considered one first hop path per counterparty.
5980 // However, as we don't restrict users to one channel per peer, we really need to support
5981 // looking at all first hop paths.
5982 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5983 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5984 // route over multiple channels with the same first hop.
5985 let secp_ctx = Secp256k1::new();
5986 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5987 let logger = Arc::new(ln_test_utils::TestLogger::new());
5988 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5989 let scorer = ln_test_utils::TestScorer::new();
5990 let config = UserConfig::default();
5991 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5992 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5993 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5996 let route_params = RouteParameters::from_payment_params_and_value(
5997 payment_params.clone(), 100_000);
5998 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5999 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6000 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6001 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6002 assert_eq!(route.paths.len(), 1);
6003 assert_eq!(route.paths[0].hops.len(), 1);
6005 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6006 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6007 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6010 let route_params = RouteParameters::from_payment_params_and_value(
6011 payment_params.clone(), 100_000);
6012 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6013 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6014 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6015 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6016 assert_eq!(route.paths.len(), 2);
6017 assert_eq!(route.paths[0].hops.len(), 1);
6018 assert_eq!(route.paths[1].hops.len(), 1);
6020 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6021 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6023 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6024 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6026 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6027 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6031 // If we have a bunch of outbound channels to the same node, where most are not
6032 // sufficient to pay the full payment, but one is, we should default to just using the
6033 // one single channel that has sufficient balance, avoiding MPP.
6035 // If we have several options above the 3xpayment value threshold, we should pick the
6036 // smallest of them, avoiding further fragmenting our available outbound balance to
6038 let route_params = RouteParameters::from_payment_params_and_value(
6039 payment_params, 100_000);
6040 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6041 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6042 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6043 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6044 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6045 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6046 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6047 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6048 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6049 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6050 assert_eq!(route.paths.len(), 1);
6051 assert_eq!(route.paths[0].hops.len(), 1);
6053 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6054 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6055 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6060 fn prefers_shorter_route_with_higher_fees() {
6061 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6062 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6063 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6065 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6066 let scorer = ln_test_utils::TestScorer::new();
6067 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6068 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6069 let route_params = RouteParameters::from_payment_params_and_value(
6070 payment_params.clone(), 100);
6071 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6072 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6073 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6075 assert_eq!(route.get_total_fees(), 100);
6076 assert_eq!(route.get_total_amount(), 100);
6077 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6079 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6080 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6081 let scorer = FixedPenaltyScorer::with_penalty(100);
6082 let route_params = RouteParameters::from_payment_params_and_value(
6083 payment_params, 100);
6084 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6085 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6086 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6088 assert_eq!(route.get_total_fees(), 300);
6089 assert_eq!(route.get_total_amount(), 100);
6090 assert_eq!(path, vec![2, 4, 7, 10]);
6093 struct BadChannelScorer {
6094 short_channel_id: u64,
6098 impl Writeable for BadChannelScorer {
6099 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6101 impl ScoreLookUp for BadChannelScorer {
6102 type ScoreParams = ();
6103 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6104 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
6108 struct BadNodeScorer {
6113 impl Writeable for BadNodeScorer {
6114 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6117 impl ScoreLookUp for BadNodeScorer {
6118 type ScoreParams = ();
6119 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6120 if *target == self.node_id { u64::max_value() } else { 0 }
6125 fn avoids_routing_through_bad_channels_and_nodes() {
6126 let (secp_ctx, network, _, _, logger) = build_graph();
6127 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6128 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6129 let network_graph = network.read_only();
6131 // A path to nodes[6] exists when no penalties are applied to any channel.
6132 let scorer = ln_test_utils::TestScorer::new();
6133 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6134 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6135 let route_params = RouteParameters::from_payment_params_and_value(
6136 payment_params, 100);
6137 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6138 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6139 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6141 assert_eq!(route.get_total_fees(), 100);
6142 assert_eq!(route.get_total_amount(), 100);
6143 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6145 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6146 let scorer = BadChannelScorer { short_channel_id: 6 };
6147 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6148 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6149 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6151 assert_eq!(route.get_total_fees(), 300);
6152 assert_eq!(route.get_total_amount(), 100);
6153 assert_eq!(path, vec![2, 4, 7, 10]);
6155 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6156 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6157 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6158 &scorer, &Default::default(), &random_seed_bytes) {
6159 Err(LightningError { err, .. } ) => {
6160 assert_eq!(err, "Failed to find a path to the given destination");
6162 Ok(_) => panic!("Expected error"),
6167 fn total_fees_single_path() {
6169 paths: vec![Path { hops: vec![
6171 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6172 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6173 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6176 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6177 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6178 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6181 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6182 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6183 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6185 ], blinded_tail: None }],
6189 assert_eq!(route.get_total_fees(), 250);
6190 assert_eq!(route.get_total_amount(), 225);
6194 fn total_fees_multi_path() {
6196 paths: vec![Path { hops: vec![
6198 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6199 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6200 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6203 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6204 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6205 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6207 ], blinded_tail: None }, Path { hops: vec![
6209 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6210 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6211 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6214 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6215 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6216 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6218 ], blinded_tail: None }],
6222 assert_eq!(route.get_total_fees(), 200);
6223 assert_eq!(route.get_total_amount(), 300);
6227 fn total_empty_route_no_panic() {
6228 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6229 // would both panic if the route was completely empty. We test to ensure they return 0
6230 // here, even though its somewhat nonsensical as a route.
6231 let route = Route { paths: Vec::new(), route_params: None };
6233 assert_eq!(route.get_total_fees(), 0);
6234 assert_eq!(route.get_total_amount(), 0);
6238 fn limits_total_cltv_delta() {
6239 let (secp_ctx, network, _, _, logger) = build_graph();
6240 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6241 let network_graph = network.read_only();
6243 let scorer = ln_test_utils::TestScorer::new();
6245 // Make sure that generally there is at least one route available
6246 let feasible_max_total_cltv_delta = 1008;
6247 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6248 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6249 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6250 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6251 let route_params = RouteParameters::from_payment_params_and_value(
6252 feasible_payment_params, 100);
6253 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6254 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6255 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6256 assert_ne!(path.len(), 0);
6258 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6259 let fail_max_total_cltv_delta = 23;
6260 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6261 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6262 let route_params = RouteParameters::from_payment_params_and_value(
6263 fail_payment_params, 100);
6264 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6265 &Default::default(), &random_seed_bytes)
6267 Err(LightningError { err, .. } ) => {
6268 assert_eq!(err, "Failed to find a path to the given destination");
6270 Ok(_) => panic!("Expected error"),
6275 fn avoids_recently_failed_paths() {
6276 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6277 // randomly inserting channels into it until we can't find a route anymore.
6278 let (secp_ctx, network, _, _, logger) = build_graph();
6279 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6280 let network_graph = network.read_only();
6282 let scorer = ln_test_utils::TestScorer::new();
6283 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6284 .with_max_path_count(1);
6285 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6286 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6288 // We should be able to find a route initially, and then after we fail a few random
6289 // channels eventually we won't be able to any longer.
6290 let route_params = RouteParameters::from_payment_params_and_value(
6291 payment_params.clone(), 100);
6292 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6293 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6295 let route_params = RouteParameters::from_payment_params_and_value(
6296 payment_params.clone(), 100);
6297 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6298 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6300 for chan in route.paths[0].hops.iter() {
6301 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6303 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6304 % route.paths[0].hops.len();
6305 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6311 fn limits_path_length() {
6312 let (secp_ctx, network, _, _, logger) = build_line_graph();
6313 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6314 let network_graph = network.read_only();
6316 let scorer = ln_test_utils::TestScorer::new();
6317 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6318 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6320 // First check we can actually create a long route on this graph.
6321 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6322 let route_params = RouteParameters::from_payment_params_and_value(
6323 feasible_payment_params, 100);
6324 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6325 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6326 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6327 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6329 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6330 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6331 let route_params = RouteParameters::from_payment_params_and_value(
6332 fail_payment_params, 100);
6333 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6334 &Default::default(), &random_seed_bytes)
6336 Err(LightningError { err, .. } ) => {
6337 assert_eq!(err, "Failed to find a path to the given destination");
6339 Ok(_) => panic!("Expected error"),
6344 fn adds_and_limits_cltv_offset() {
6345 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6346 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6348 let scorer = ln_test_utils::TestScorer::new();
6350 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6351 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6352 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6353 let route_params = RouteParameters::from_payment_params_and_value(
6354 payment_params.clone(), 100);
6355 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6356 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6357 assert_eq!(route.paths.len(), 1);
6359 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6361 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6362 let mut route_default = route.clone();
6363 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6364 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6365 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6366 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6367 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6369 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6370 let mut route_limited = route.clone();
6371 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6372 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6373 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6374 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6375 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6379 fn adds_plausible_cltv_offset() {
6380 let (secp_ctx, network, _, _, logger) = build_graph();
6381 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6382 let network_graph = network.read_only();
6383 let network_nodes = network_graph.nodes();
6384 let network_channels = network_graph.channels();
6385 let scorer = ln_test_utils::TestScorer::new();
6386 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6387 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6388 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6390 let route_params = RouteParameters::from_payment_params_and_value(
6391 payment_params.clone(), 100);
6392 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6393 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6394 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6396 let mut path_plausibility = vec![];
6398 for p in route.paths {
6399 // 1. Select random observation point
6400 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6401 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6403 prng.process_in_place(&mut random_bytes);
6404 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6405 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6407 // 2. Calculate what CLTV expiry delta we would observe there
6408 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6410 // 3. Starting from the observation point, find candidate paths
6411 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6412 candidates.push_back((observation_point, vec![]));
6414 let mut found_plausible_candidate = false;
6416 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6417 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6418 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6419 found_plausible_candidate = true;
6420 break 'candidate_loop;
6424 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6425 for channel_id in &cur_node.channels {
6426 if let Some(channel_info) = network_channels.get(&channel_id) {
6427 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6428 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6429 if cur_path_cltv_deltas.iter().sum::<u32>()
6430 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6431 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6432 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6433 candidates.push_back((*next_id, new_path_cltv_deltas));
6441 path_plausibility.push(found_plausible_candidate);
6443 assert!(path_plausibility.iter().all(|x| *x));
6447 fn builds_correct_path_from_hops() {
6448 let (secp_ctx, network, _, _, logger) = build_graph();
6449 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6450 let network_graph = network.read_only();
6452 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6453 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6455 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6456 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6457 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6458 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6459 Arc::clone(&logger), &random_seed_bytes).unwrap();
6460 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6461 assert_eq!(hops.len(), route.paths[0].hops.len());
6462 for (idx, hop_pubkey) in hops.iter().enumerate() {
6463 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6468 fn avoids_saturating_channels() {
6469 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6470 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6471 let decay_params = ProbabilisticScoringDecayParameters::default();
6472 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6474 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6475 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6476 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6477 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6478 short_channel_id: 4,
6481 cltv_expiry_delta: (4 << 4) | 1,
6482 htlc_minimum_msat: 0,
6483 htlc_maximum_msat: 250_000_000,
6485 fee_proportional_millionths: 0,
6486 excess_data: Vec::new()
6488 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6489 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6490 short_channel_id: 13,
6493 cltv_expiry_delta: (13 << 4) | 1,
6494 htlc_minimum_msat: 0,
6495 htlc_maximum_msat: 250_000_000,
6497 fee_proportional_millionths: 0,
6498 excess_data: Vec::new()
6501 let config = UserConfig::default();
6502 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6503 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6504 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6505 // 100,000 sats is less than the available liquidity on each channel, set above.
6506 let route_params = RouteParameters::from_payment_params_and_value(
6507 payment_params, 100_000_000);
6508 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6509 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6510 assert_eq!(route.paths.len(), 2);
6511 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6512 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6515 #[cfg(not(feature = "no-std"))]
6516 pub(super) fn random_init_seed() -> u64 {
6517 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6518 use core::hash::{BuildHasher, Hasher};
6519 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6520 println!("Using seed of {}", seed);
6525 #[cfg(not(feature = "no-std"))]
6526 fn generate_routes() {
6527 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6529 let logger = ln_test_utils::TestLogger::new();
6530 let graph = match super::bench_utils::read_network_graph(&logger) {
6538 let params = ProbabilisticScoringFeeParameters::default();
6539 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6540 let features = super::Bolt11InvoiceFeatures::empty();
6542 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6546 #[cfg(not(feature = "no-std"))]
6547 fn generate_routes_mpp() {
6548 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6550 let logger = ln_test_utils::TestLogger::new();
6551 let graph = match super::bench_utils::read_network_graph(&logger) {
6559 let params = ProbabilisticScoringFeeParameters::default();
6560 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6561 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6563 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6567 #[cfg(not(feature = "no-std"))]
6568 fn generate_large_mpp_routes() {
6569 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6571 let logger = ln_test_utils::TestLogger::new();
6572 let graph = match super::bench_utils::read_network_graph(&logger) {
6580 let params = ProbabilisticScoringFeeParameters::default();
6581 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6582 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6584 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6588 fn honors_manual_penalties() {
6589 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6590 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6592 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6593 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6595 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6596 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6598 // First check set manual penalties are returned by the scorer.
6599 let usage = ChannelUsage {
6601 inflight_htlc_msat: 0,
6602 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6604 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6605 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6606 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6608 // Then check we can get a normal route
6609 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6610 let route_params = RouteParameters::from_payment_params_and_value(
6611 payment_params, 100);
6612 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6613 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6614 assert!(route.is_ok());
6616 // Then check that we can't get a route if we ban an intermediate node.
6617 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6618 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6619 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6620 assert!(route.is_err());
6622 // Finally make sure we can route again, when we remove the ban.
6623 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6624 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6625 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6626 assert!(route.is_ok());
6630 fn abide_by_route_hint_max_htlc() {
6631 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6632 // params in the final route.
6633 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6634 let netgraph = network_graph.read_only();
6635 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6636 let scorer = ln_test_utils::TestScorer::new();
6637 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6638 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6639 let config = UserConfig::default();
6641 let max_htlc_msat = 50_000;
6642 let route_hint_1 = RouteHint(vec![RouteHintHop {
6643 src_node_id: nodes[2],
6644 short_channel_id: 42,
6647 proportional_millionths: 0,
6649 cltv_expiry_delta: 10,
6650 htlc_minimum_msat: None,
6651 htlc_maximum_msat: Some(max_htlc_msat),
6653 let dest_node_id = ln_test_utils::pubkey(42);
6654 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6655 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6656 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6658 // Make sure we'll error if our route hints don't have enough liquidity according to their
6659 // htlc_maximum_msat.
6660 let mut route_params = RouteParameters::from_payment_params_and_value(
6661 payment_params, max_htlc_msat + 1);
6662 route_params.max_total_routing_fee_msat = None;
6663 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6664 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6667 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6668 } else { panic!(); }
6670 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6671 let mut route_hint_2 = route_hint_1.clone();
6672 route_hint_2.0[0].short_channel_id = 43;
6673 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6674 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6675 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6676 let mut route_params = RouteParameters::from_payment_params_and_value(
6677 payment_params, max_htlc_msat + 1);
6678 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6679 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6680 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6681 assert_eq!(route.paths.len(), 2);
6682 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6683 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6687 fn direct_channel_to_hints_with_max_htlc() {
6688 // Check that if we have a first hop channel peer that's connected to multiple provided route
6689 // hints, that we properly split the payment between the route hints if needed.
6690 let logger = Arc::new(ln_test_utils::TestLogger::new());
6691 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6692 let scorer = ln_test_utils::TestScorer::new();
6693 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6694 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6695 let config = UserConfig::default();
6697 let our_node_id = ln_test_utils::pubkey(42);
6698 let intermed_node_id = ln_test_utils::pubkey(43);
6699 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6701 let amt_msat = 900_000;
6702 let max_htlc_msat = 500_000;
6703 let route_hint_1 = RouteHint(vec![RouteHintHop {
6704 src_node_id: intermed_node_id,
6705 short_channel_id: 44,
6708 proportional_millionths: 0,
6710 cltv_expiry_delta: 10,
6711 htlc_minimum_msat: None,
6712 htlc_maximum_msat: Some(max_htlc_msat),
6714 src_node_id: intermed_node_id,
6715 short_channel_id: 45,
6718 proportional_millionths: 0,
6720 cltv_expiry_delta: 10,
6721 htlc_minimum_msat: None,
6722 // Check that later route hint max htlcs don't override earlier ones
6723 htlc_maximum_msat: Some(max_htlc_msat - 50),
6725 let mut route_hint_2 = route_hint_1.clone();
6726 route_hint_2.0[0].short_channel_id = 46;
6727 route_hint_2.0[1].short_channel_id = 47;
6728 let dest_node_id = ln_test_utils::pubkey(44);
6729 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6730 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6731 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6733 let route_params = RouteParameters::from_payment_params_and_value(
6734 payment_params, amt_msat);
6735 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6736 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6737 &Default::default(), &random_seed_bytes).unwrap();
6738 assert_eq!(route.paths.len(), 2);
6739 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6740 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6741 assert_eq!(route.get_total_amount(), amt_msat);
6743 // Re-run but with two first hop channels connected to the same route hint peers that must be
6745 let first_hops = vec![
6746 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6747 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6749 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6750 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6751 &Default::default(), &random_seed_bytes).unwrap();
6752 assert_eq!(route.paths.len(), 2);
6753 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6754 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6755 assert_eq!(route.get_total_amount(), amt_msat);
6757 // Make sure this works for blinded route hints.
6758 let blinded_path = BlindedPath {
6759 introduction_node_id: intermed_node_id,
6760 blinding_point: ln_test_utils::pubkey(42),
6762 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6763 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6766 let blinded_payinfo = BlindedPayInfo {
6768 fee_proportional_millionths: 0,
6769 htlc_minimum_msat: 1,
6770 htlc_maximum_msat: max_htlc_msat,
6771 cltv_expiry_delta: 10,
6772 features: BlindedHopFeatures::empty(),
6774 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6775 let payment_params = PaymentParameters::blinded(vec![
6776 (blinded_payinfo.clone(), blinded_path.clone()),
6777 (blinded_payinfo.clone(), blinded_path.clone())])
6778 .with_bolt12_features(bolt12_features).unwrap();
6779 let route_params = RouteParameters::from_payment_params_and_value(
6780 payment_params, amt_msat);
6781 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6782 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6783 &Default::default(), &random_seed_bytes).unwrap();
6784 assert_eq!(route.paths.len(), 2);
6785 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6786 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6787 assert_eq!(route.get_total_amount(), amt_msat);
6791 fn blinded_route_ser() {
6792 let blinded_path_1 = BlindedPath {
6793 introduction_node_id: ln_test_utils::pubkey(42),
6794 blinding_point: ln_test_utils::pubkey(43),
6796 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6797 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6800 let blinded_path_2 = BlindedPath {
6801 introduction_node_id: ln_test_utils::pubkey(46),
6802 blinding_point: ln_test_utils::pubkey(47),
6804 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6805 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6808 // (De)serialize a Route with 1 blinded path out of two total paths.
6809 let mut route = Route { paths: vec![Path {
6810 hops: vec![RouteHop {
6811 pubkey: ln_test_utils::pubkey(50),
6812 node_features: NodeFeatures::empty(),
6813 short_channel_id: 42,
6814 channel_features: ChannelFeatures::empty(),
6816 cltv_expiry_delta: 0,
6817 maybe_announced_channel: true,
6819 blinded_tail: Some(BlindedTail {
6820 hops: blinded_path_1.blinded_hops,
6821 blinding_point: blinded_path_1.blinding_point,
6822 excess_final_cltv_expiry_delta: 40,
6823 final_value_msat: 100,
6825 hops: vec![RouteHop {
6826 pubkey: ln_test_utils::pubkey(51),
6827 node_features: NodeFeatures::empty(),
6828 short_channel_id: 43,
6829 channel_features: ChannelFeatures::empty(),
6831 cltv_expiry_delta: 0,
6832 maybe_announced_channel: true,
6833 }], blinded_tail: None }],
6836 let encoded_route = route.encode();
6837 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6838 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6839 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6841 // (De)serialize a Route with two paths, each containing a blinded tail.
6842 route.paths[1].blinded_tail = Some(BlindedTail {
6843 hops: blinded_path_2.blinded_hops,
6844 blinding_point: blinded_path_2.blinding_point,
6845 excess_final_cltv_expiry_delta: 41,
6846 final_value_msat: 101,
6848 let encoded_route = route.encode();
6849 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6850 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6851 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6855 fn blinded_path_inflight_processing() {
6856 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6857 // account for the blinded tail's final amount_msat.
6858 let mut inflight_htlcs = InFlightHtlcs::new();
6859 let blinded_path = BlindedPath {
6860 introduction_node_id: ln_test_utils::pubkey(43),
6861 blinding_point: ln_test_utils::pubkey(48),
6862 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6865 hops: vec![RouteHop {
6866 pubkey: ln_test_utils::pubkey(42),
6867 node_features: NodeFeatures::empty(),
6868 short_channel_id: 42,
6869 channel_features: ChannelFeatures::empty(),
6871 cltv_expiry_delta: 0,
6872 maybe_announced_channel: false,
6875 pubkey: blinded_path.introduction_node_id,
6876 node_features: NodeFeatures::empty(),
6877 short_channel_id: 43,
6878 channel_features: ChannelFeatures::empty(),
6880 cltv_expiry_delta: 0,
6881 maybe_announced_channel: false,
6883 blinded_tail: Some(BlindedTail {
6884 hops: blinded_path.blinded_hops,
6885 blinding_point: blinded_path.blinding_point,
6886 excess_final_cltv_expiry_delta: 0,
6887 final_value_msat: 200,
6890 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6891 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6892 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6896 fn blinded_path_cltv_shadow_offset() {
6897 // Make sure we add a shadow offset when sending to blinded paths.
6898 let blinded_path = BlindedPath {
6899 introduction_node_id: ln_test_utils::pubkey(43),
6900 blinding_point: ln_test_utils::pubkey(44),
6902 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6903 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6906 let mut route = Route { paths: vec![Path {
6907 hops: vec![RouteHop {
6908 pubkey: ln_test_utils::pubkey(42),
6909 node_features: NodeFeatures::empty(),
6910 short_channel_id: 42,
6911 channel_features: ChannelFeatures::empty(),
6913 cltv_expiry_delta: 0,
6914 maybe_announced_channel: false,
6917 pubkey: blinded_path.introduction_node_id,
6918 node_features: NodeFeatures::empty(),
6919 short_channel_id: 43,
6920 channel_features: ChannelFeatures::empty(),
6922 cltv_expiry_delta: 0,
6923 maybe_announced_channel: false,
6926 blinded_tail: Some(BlindedTail {
6927 hops: blinded_path.blinded_hops,
6928 blinding_point: blinded_path.blinding_point,
6929 excess_final_cltv_expiry_delta: 0,
6930 final_value_msat: 200,
6932 }], route_params: None};
6934 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6935 let (_, network_graph, _, _, _) = build_line_graph();
6936 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6937 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6938 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6942 fn simple_blinded_route_hints() {
6943 do_simple_blinded_route_hints(1);
6944 do_simple_blinded_route_hints(2);
6945 do_simple_blinded_route_hints(3);
6948 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6949 // Check that we can generate a route to a blinded path with the expected hops.
6950 let (secp_ctx, network, _, _, logger) = build_graph();
6951 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6952 let network_graph = network.read_only();
6954 let scorer = ln_test_utils::TestScorer::new();
6955 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6956 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6958 let mut blinded_path = BlindedPath {
6959 introduction_node_id: nodes[2],
6960 blinding_point: ln_test_utils::pubkey(42),
6961 blinded_hops: Vec::with_capacity(num_blinded_hops),
6963 for i in 0..num_blinded_hops {
6964 blinded_path.blinded_hops.push(
6965 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6968 let blinded_payinfo = BlindedPayInfo {
6970 fee_proportional_millionths: 500,
6971 htlc_minimum_msat: 1000,
6972 htlc_maximum_msat: 100_000_000,
6973 cltv_expiry_delta: 15,
6974 features: BlindedHopFeatures::empty(),
6977 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6978 let route_params = RouteParameters::from_payment_params_and_value(
6979 payment_params, 1001);
6980 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6981 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6982 assert_eq!(route.paths.len(), 1);
6983 assert_eq!(route.paths[0].hops.len(), 2);
6985 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6986 assert_eq!(tail.hops, blinded_path.blinded_hops);
6987 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6988 assert_eq!(tail.final_value_msat, 1001);
6990 let final_hop = route.paths[0].hops.last().unwrap();
6991 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6992 if tail.hops.len() > 1 {
6993 assert_eq!(final_hop.fee_msat,
6994 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6995 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6997 assert_eq!(final_hop.fee_msat, 0);
6998 assert_eq!(final_hop.cltv_expiry_delta, 0);
7003 fn blinded_path_routing_errors() {
7004 // Check that we can generate a route to a blinded path with the expected hops.
7005 let (secp_ctx, network, _, _, logger) = build_graph();
7006 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7007 let network_graph = network.read_only();
7009 let scorer = ln_test_utils::TestScorer::new();
7010 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7011 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7013 let mut invalid_blinded_path = BlindedPath {
7014 introduction_node_id: nodes[2],
7015 blinding_point: ln_test_utils::pubkey(42),
7017 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7020 let blinded_payinfo = BlindedPayInfo {
7022 fee_proportional_millionths: 500,
7023 htlc_minimum_msat: 1000,
7024 htlc_maximum_msat: 100_000_000,
7025 cltv_expiry_delta: 15,
7026 features: BlindedHopFeatures::empty(),
7029 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7030 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7031 let payment_params = PaymentParameters::blinded(vec![
7032 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7033 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7034 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7035 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7036 &scorer, &Default::default(), &random_seed_bytes)
7038 Err(LightningError { err, .. }) => {
7039 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7041 _ => panic!("Expected error")
7044 invalid_blinded_path.introduction_node_id = our_id;
7045 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7046 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7047 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7048 &Default::default(), &random_seed_bytes)
7050 Err(LightningError { err, .. }) => {
7051 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7053 _ => panic!("Expected error")
7056 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7057 invalid_blinded_path.blinded_hops.clear();
7058 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7059 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7060 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7061 &Default::default(), &random_seed_bytes)
7063 Err(LightningError { err, .. }) => {
7064 assert_eq!(err, "0-hop blinded path provided");
7066 _ => panic!("Expected error")
7071 fn matching_intro_node_paths_provided() {
7072 // Check that if multiple blinded paths with the same intro node are provided in payment
7073 // parameters, we'll return the correct paths in the resulting MPP route.
7074 let (secp_ctx, network, _, _, logger) = build_graph();
7075 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7076 let network_graph = network.read_only();
7078 let scorer = ln_test_utils::TestScorer::new();
7079 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7080 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7081 let config = UserConfig::default();
7083 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7084 let blinded_path_1 = BlindedPath {
7085 introduction_node_id: nodes[2],
7086 blinding_point: ln_test_utils::pubkey(42),
7088 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7089 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7092 let blinded_payinfo_1 = BlindedPayInfo {
7094 fee_proportional_millionths: 0,
7095 htlc_minimum_msat: 0,
7096 htlc_maximum_msat: 30_000,
7097 cltv_expiry_delta: 0,
7098 features: BlindedHopFeatures::empty(),
7101 let mut blinded_path_2 = blinded_path_1.clone();
7102 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7103 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7104 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7106 let blinded_hints = vec![
7107 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7108 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7110 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7111 .with_bolt12_features(bolt12_features.clone()).unwrap();
7113 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7114 route_params.max_total_routing_fee_msat = Some(100_000);
7115 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7116 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7117 assert_eq!(route.paths.len(), 2);
7118 let mut total_amount_paid_msat = 0;
7119 for path in route.paths.into_iter() {
7120 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7121 if let Some(bt) = &path.blinded_tail {
7122 assert_eq!(bt.blinding_point,
7123 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7124 .map(|(_, bp)| bp.blinding_point).unwrap());
7125 } else { panic!(); }
7126 total_amount_paid_msat += path.final_value_msat();
7128 assert_eq!(total_amount_paid_msat, 100_000);
7132 fn direct_to_intro_node() {
7133 // This previously caused a debug panic in the router when asserting
7134 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7135 // direct channels we failed to account for the fee charged for use of the blinded path.
7138 // node0 -1(1)2 - node1
7139 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7140 // doesn't account for the blinded path fee.
7142 let secp_ctx = Secp256k1::new();
7143 let logger = Arc::new(ln_test_utils::TestLogger::new());
7144 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7145 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7146 let scorer = ln_test_utils::TestScorer::new();
7147 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7148 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7150 let amt_msat = 10_000_000;
7151 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7152 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7153 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7154 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7156 short_channel_id: 1,
7159 cltv_expiry_delta: 42,
7160 htlc_minimum_msat: 1_000,
7161 htlc_maximum_msat: 10_000_000,
7163 fee_proportional_millionths: 0,
7164 excess_data: Vec::new()
7166 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7167 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7168 short_channel_id: 1,
7171 cltv_expiry_delta: 42,
7172 htlc_minimum_msat: 1_000,
7173 htlc_maximum_msat: 10_000_000,
7175 fee_proportional_millionths: 0,
7176 excess_data: Vec::new()
7178 let first_hops = vec![
7179 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7181 let blinded_path = BlindedPath {
7182 introduction_node_id: nodes[1],
7183 blinding_point: ln_test_utils::pubkey(42),
7185 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7186 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7189 let blinded_payinfo = BlindedPayInfo {
7190 fee_base_msat: 1000,
7191 fee_proportional_millionths: 0,
7192 htlc_minimum_msat: 1000,
7193 htlc_maximum_msat: MAX_VALUE_MSAT,
7194 cltv_expiry_delta: 0,
7195 features: BlindedHopFeatures::empty(),
7197 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7199 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7201 let netgraph = network_graph.read_only();
7202 let route_params = RouteParameters::from_payment_params_and_value(
7203 payment_params.clone(), amt_msat);
7204 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7205 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7206 &Default::default(), &random_seed_bytes) {
7207 assert_eq!(err, "Failed to find a path to the given destination");
7208 } else { panic!("Expected error") }
7210 // Sending an exact amount accounting for the blinded path fee works.
7211 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7212 let route_params = RouteParameters::from_payment_params_and_value(
7213 payment_params, amt_minus_blinded_path_fee);
7214 let route = get_route(&nodes[0], &route_params, &netgraph,
7215 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7216 &Default::default(), &random_seed_bytes).unwrap();
7217 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7218 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7222 fn direct_to_matching_intro_nodes() {
7223 // This previously caused us to enter `unreachable` code in the following situation:
7224 // 1. We add a route candidate for intro_node contributing a high amount
7225 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7226 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7227 // amount, and update our route candidate for intro_node for the lower amount
7228 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7229 // lower contribution amount, but fail (this was previously caused by failure to account for
7230 // blinded path fees when adding first_hop<>intro_node candidates)
7231 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7232 // candidate still thinks its path is contributing the original higher amount. This caused us
7233 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7235 let secp_ctx = Secp256k1::new();
7236 let logger = Arc::new(ln_test_utils::TestLogger::new());
7237 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7238 let scorer = ln_test_utils::TestScorer::new();
7239 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7240 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7241 let config = UserConfig::default();
7243 // Values are taken from the fuzz input that uncovered this panic.
7244 let amt_msat = 21_7020_5185_1403_2640;
7245 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7246 let first_hops = vec![
7247 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7248 18446744073709551615)];
7250 let blinded_path = BlindedPath {
7251 introduction_node_id: nodes[1],
7252 blinding_point: ln_test_utils::pubkey(42),
7254 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7255 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7258 let blinded_payinfo = BlindedPayInfo {
7259 fee_base_msat: 5046_2720,
7260 fee_proportional_millionths: 0,
7261 htlc_minimum_msat: 4503_5996_2737_0496,
7262 htlc_maximum_msat: 45_0359_9627_3704_9600,
7263 cltv_expiry_delta: 0,
7264 features: BlindedHopFeatures::empty(),
7266 let mut blinded_hints = vec![
7267 (blinded_payinfo.clone(), blinded_path.clone()),
7268 (blinded_payinfo.clone(), blinded_path.clone()),
7270 blinded_hints[1].0.fee_base_msat = 419_4304;
7271 blinded_hints[1].0.fee_proportional_millionths = 257;
7272 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7273 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7274 blinded_hints[1].0.cltv_expiry_delta = 0;
7276 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7277 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7278 .with_bolt12_features(bolt12_features.clone()).unwrap();
7280 let netgraph = network_graph.read_only();
7281 let route_params = RouteParameters::from_payment_params_and_value(
7282 payment_params, amt_msat);
7283 let route = get_route(&nodes[0], &route_params, &netgraph,
7284 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7285 &Default::default(), &random_seed_bytes).unwrap();
7286 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7287 assert_eq!(route.get_total_amount(), amt_msat);
7291 fn we_are_intro_node_candidate_hops() {
7292 // This previously led to a panic in the router because we'd generate a Path with only a
7293 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7294 // where the origin node is the intro node. We now fully disallow considering candidate hops
7295 // where the origin node is the intro node.
7296 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7297 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7298 let scorer = ln_test_utils::TestScorer::new();
7299 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7300 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7301 let config = UserConfig::default();
7303 // Values are taken from the fuzz input that uncovered this panic.
7304 let amt_msat = 21_7020_5185_1423_0019;
7306 let blinded_path = BlindedPath {
7307 introduction_node_id: our_id,
7308 blinding_point: ln_test_utils::pubkey(42),
7310 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7311 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7314 let blinded_payinfo = BlindedPayInfo {
7315 fee_base_msat: 5052_9027,
7316 fee_proportional_millionths: 0,
7317 htlc_minimum_msat: 21_7020_5185_1423_0019,
7318 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7319 cltv_expiry_delta: 0,
7320 features: BlindedHopFeatures::empty(),
7322 let mut blinded_hints = vec![
7323 (blinded_payinfo.clone(), blinded_path.clone()),
7324 (blinded_payinfo.clone(), blinded_path.clone()),
7326 blinded_hints[1].1.introduction_node_id = nodes[6];
7328 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7329 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7330 .with_bolt12_features(bolt12_features.clone()).unwrap();
7332 let netgraph = network_graph.read_only();
7333 let route_params = RouteParameters::from_payment_params_and_value(
7334 payment_params, amt_msat);
7335 if let Err(LightningError { err, .. }) = get_route(
7336 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7338 assert_eq!(err, "Failed to find a path to the given destination");
7343 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7344 // This previously led to a debug panic in the router because we'd find an invalid Path with
7345 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7346 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7347 // the payment, when it was intended to only include the final value of the payment.
7348 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7349 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7350 let scorer = ln_test_utils::TestScorer::new();
7351 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7352 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7353 let config = UserConfig::default();
7355 // Values are taken from the fuzz input that uncovered this panic.
7356 let amt_msat = 21_7020_5185_1423_0019;
7358 let blinded_path = BlindedPath {
7359 introduction_node_id: our_id,
7360 blinding_point: ln_test_utils::pubkey(42),
7362 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7363 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7366 let blinded_payinfo = BlindedPayInfo {
7367 fee_base_msat: 10_4425_1395,
7368 fee_proportional_millionths: 0,
7369 htlc_minimum_msat: 21_7301_9934_9094_0931,
7370 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7371 cltv_expiry_delta: 0,
7372 features: BlindedHopFeatures::empty(),
7374 let mut blinded_hints = vec![
7375 (blinded_payinfo.clone(), blinded_path.clone()),
7376 (blinded_payinfo.clone(), blinded_path.clone()),
7377 (blinded_payinfo.clone(), blinded_path.clone()),
7379 blinded_hints[1].0.fee_base_msat = 5052_9027;
7380 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7381 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7383 blinded_hints[2].1.introduction_node_id = nodes[6];
7385 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7386 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7387 .with_bolt12_features(bolt12_features.clone()).unwrap();
7389 let netgraph = network_graph.read_only();
7390 let route_params = RouteParameters::from_payment_params_and_value(
7391 payment_params, amt_msat);
7392 if let Err(LightningError { err, .. }) = get_route(
7393 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7395 assert_eq!(err, "Failed to find a path to the given destination");
7400 fn min_htlc_overpay_violates_max_htlc() {
7401 do_min_htlc_overpay_violates_max_htlc(true);
7402 do_min_htlc_overpay_violates_max_htlc(false);
7404 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7405 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7406 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7407 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7408 // that the used liquidity for a hop was less than its available liquidity limit.
7409 let secp_ctx = Secp256k1::new();
7410 let logger = Arc::new(ln_test_utils::TestLogger::new());
7411 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7412 let scorer = ln_test_utils::TestScorer::new();
7413 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7414 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7415 let config = UserConfig::default();
7417 // Values are taken from the fuzz input that uncovered this panic.
7418 let amt_msat = 7_4009_8048;
7419 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7420 let first_hop_outbound_capacity = 2_7345_2000;
7421 let first_hops = vec![get_channel_details(
7422 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7423 first_hop_outbound_capacity
7426 let base_fee = 1_6778_3453;
7427 let htlc_min = 2_5165_8240;
7428 let payment_params = if blinded_payee {
7429 let blinded_path = BlindedPath {
7430 introduction_node_id: nodes[0],
7431 blinding_point: ln_test_utils::pubkey(42),
7433 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7434 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7437 let blinded_payinfo = BlindedPayInfo {
7438 fee_base_msat: base_fee,
7439 fee_proportional_millionths: 0,
7440 htlc_minimum_msat: htlc_min,
7441 htlc_maximum_msat: htlc_min * 1000,
7442 cltv_expiry_delta: 0,
7443 features: BlindedHopFeatures::empty(),
7445 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7446 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7447 .with_bolt12_features(bolt12_features.clone()).unwrap()
7449 let route_hint = RouteHint(vec![RouteHintHop {
7450 src_node_id: nodes[0],
7451 short_channel_id: 42,
7453 base_msat: base_fee,
7454 proportional_millionths: 0,
7456 cltv_expiry_delta: 10,
7457 htlc_minimum_msat: Some(htlc_min),
7458 htlc_maximum_msat: None,
7461 PaymentParameters::from_node_id(nodes[1], 42)
7462 .with_route_hints(vec![route_hint]).unwrap()
7463 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7466 let netgraph = network_graph.read_only();
7467 let route_params = RouteParameters::from_payment_params_and_value(
7468 payment_params, amt_msat);
7469 if let Err(LightningError { err, .. }) = get_route(
7470 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7471 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7473 assert_eq!(err, "Failed to find a path to the given destination");
7478 fn previously_used_liquidity_violates_max_htlc() {
7479 do_previously_used_liquidity_violates_max_htlc(true);
7480 do_previously_used_liquidity_violates_max_htlc(false);
7483 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7484 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7485 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7486 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7487 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7488 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7489 let secp_ctx = Secp256k1::new();
7490 let logger = Arc::new(ln_test_utils::TestLogger::new());
7491 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7492 let scorer = ln_test_utils::TestScorer::new();
7493 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7494 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7495 let config = UserConfig::default();
7497 // Values are taken from the fuzz input that uncovered this panic.
7498 let amt_msat = 52_4288;
7499 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7500 let first_hops = vec![get_channel_details(
7501 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7502 ), get_channel_details(
7503 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7506 let base_fees = [0, 425_9840, 0, 0];
7507 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7508 let payment_params = if blinded_payee {
7509 let blinded_path = BlindedPath {
7510 introduction_node_id: nodes[0],
7511 blinding_point: ln_test_utils::pubkey(42),
7513 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7514 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7517 let mut blinded_hints = Vec::new();
7518 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7519 blinded_hints.push((BlindedPayInfo {
7520 fee_base_msat: *base_fee,
7521 fee_proportional_millionths: 0,
7522 htlc_minimum_msat: *htlc_min,
7523 htlc_maximum_msat: htlc_min * 100,
7524 cltv_expiry_delta: 10,
7525 features: BlindedHopFeatures::empty(),
7526 }, blinded_path.clone()));
7528 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7529 PaymentParameters::blinded(blinded_hints.clone())
7530 .with_bolt12_features(bolt12_features.clone()).unwrap()
7532 let mut route_hints = Vec::new();
7533 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7534 route_hints.push(RouteHint(vec![RouteHintHop {
7535 src_node_id: nodes[0],
7536 short_channel_id: 42 + idx as u64,
7538 base_msat: *base_fee,
7539 proportional_millionths: 0,
7541 cltv_expiry_delta: 10,
7542 htlc_minimum_msat: Some(*htlc_min),
7543 htlc_maximum_msat: Some(htlc_min * 100),
7546 PaymentParameters::from_node_id(nodes[1], 42)
7547 .with_route_hints(route_hints).unwrap()
7548 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7551 let netgraph = network_graph.read_only();
7552 let route_params = RouteParameters::from_payment_params_and_value(
7553 payment_params, amt_msat);
7555 let route = get_route(
7556 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7557 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7559 assert_eq!(route.paths.len(), 1);
7560 assert_eq!(route.get_total_amount(), amt_msat);
7564 fn candidate_path_min() {
7565 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7566 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7567 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7568 // would add a connecting first_hop node that did not have enough contribution amount, leading
7569 // to a debug panic upon invalid path construction.
7570 let secp_ctx = Secp256k1::new();
7571 let logger = Arc::new(ln_test_utils::TestLogger::new());
7572 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7573 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7574 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7575 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7576 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7577 let config = UserConfig::default();
7579 // Values are taken from the fuzz input that uncovered this panic.
7580 let amt_msat = 7_4009_8048;
7581 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7582 let first_hops = vec![get_channel_details(
7583 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7586 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7587 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7588 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7589 short_channel_id: 6,
7592 cltv_expiry_delta: (6 << 4) | 0,
7593 htlc_minimum_msat: 0,
7594 htlc_maximum_msat: MAX_VALUE_MSAT,
7596 fee_proportional_millionths: 0,
7597 excess_data: Vec::new()
7599 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7601 let htlc_min = 2_5165_8240;
7602 let blinded_hints = vec![
7604 fee_base_msat: 1_6778_3453,
7605 fee_proportional_millionths: 0,
7606 htlc_minimum_msat: htlc_min,
7607 htlc_maximum_msat: htlc_min * 100,
7608 cltv_expiry_delta: 10,
7609 features: BlindedHopFeatures::empty(),
7611 introduction_node_id: nodes[0],
7612 blinding_point: ln_test_utils::pubkey(42),
7614 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7615 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7619 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7620 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7621 .with_bolt12_features(bolt12_features.clone()).unwrap();
7622 let route_params = RouteParameters::from_payment_params_and_value(
7623 payment_params, amt_msat);
7624 let netgraph = network_graph.read_only();
7626 if let Err(LightningError { err, .. }) = get_route(
7627 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7628 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7631 assert_eq!(err, "Failed to find a path to the given destination");
7636 fn path_contribution_includes_min_htlc_overpay() {
7637 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7638 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7639 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7640 // selection, both tested here.
7641 let secp_ctx = Secp256k1::new();
7642 let logger = Arc::new(ln_test_utils::TestLogger::new());
7643 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7644 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7645 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7646 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7647 let config = UserConfig::default();
7649 // Values are taken from the fuzz input that uncovered this panic.
7650 let amt_msat = 562_0000;
7651 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7652 let first_hops = vec![
7653 get_channel_details(
7654 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7658 let htlc_mins = [49_0000, 1125_0000];
7659 let payment_params = {
7660 let blinded_path = BlindedPath {
7661 introduction_node_id: nodes[0],
7662 blinding_point: ln_test_utils::pubkey(42),
7664 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7665 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7668 let mut blinded_hints = Vec::new();
7669 for htlc_min in htlc_mins.iter() {
7670 blinded_hints.push((BlindedPayInfo {
7672 fee_proportional_millionths: 0,
7673 htlc_minimum_msat: *htlc_min,
7674 htlc_maximum_msat: *htlc_min * 100,
7675 cltv_expiry_delta: 10,
7676 features: BlindedHopFeatures::empty(),
7677 }, blinded_path.clone()));
7679 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7680 PaymentParameters::blinded(blinded_hints.clone())
7681 .with_bolt12_features(bolt12_features.clone()).unwrap()
7684 let netgraph = network_graph.read_only();
7685 let route_params = RouteParameters::from_payment_params_and_value(
7686 payment_params, amt_msat);
7687 let route = get_route(
7688 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7689 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7692 assert_eq!(route.paths.len(), 1);
7693 assert_eq!(route.get_total_amount(), amt_msat);
7697 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7698 pub(crate) mod bench_utils {
7702 use bitcoin::hashes::Hash;
7703 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7705 use crate::chain::transaction::OutPoint;
7706 use crate::routing::scoring::ScoreUpdate;
7707 use crate::sign::{EntropySource, KeysManager};
7708 use crate::ln::ChannelId;
7709 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7710 use crate::ln::features::Bolt11InvoiceFeatures;
7711 use crate::routing::gossip::NetworkGraph;
7712 use crate::util::config::UserConfig;
7713 use crate::util::ser::ReadableArgs;
7714 use crate::util::test_utils::TestLogger;
7716 /// Tries to open a network graph file, or panics with a URL to fetch it.
7717 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7718 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7719 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7720 .or_else(|_| { // Fall back to guessing based on the binary location
7721 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7722 let mut path = std::env::current_exe().unwrap();
7723 path.pop(); // lightning-...
7725 path.pop(); // debug
7726 path.pop(); // target
7727 path.push("lightning");
7728 path.push("net_graph-2023-01-18.bin");
7731 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7732 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7733 let mut path = std::env::current_exe().unwrap();
7734 path.pop(); // bench...
7736 path.pop(); // debug
7737 path.pop(); // target
7738 path.pop(); // bench
7739 path.push("lightning");
7740 path.push("net_graph-2023-01-18.bin");
7743 .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");
7744 #[cfg(require_route_graph_test)]
7745 return Ok(res.unwrap());
7746 #[cfg(not(require_route_graph_test))]
7750 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7751 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7754 pub(crate) fn payer_pubkey() -> PublicKey {
7755 let secp_ctx = Secp256k1::new();
7756 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7760 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7762 channel_id: ChannelId::new_zero(),
7763 counterparty: ChannelCounterparty {
7764 features: channelmanager::provided_init_features(&UserConfig::default()),
7766 unspendable_punishment_reserve: 0,
7767 forwarding_info: None,
7768 outbound_htlc_minimum_msat: None,
7769 outbound_htlc_maximum_msat: None,
7771 funding_txo: Some(OutPoint {
7772 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7775 short_channel_id: Some(1),
7776 inbound_scid_alias: None,
7777 outbound_scid_alias: None,
7778 channel_value_satoshis: 10_000_000_000,
7780 outbound_capacity_msat: 10_000_000_000,
7781 next_outbound_htlc_minimum_msat: 0,
7782 next_outbound_htlc_limit_msat: 10_000_000_000,
7783 inbound_capacity_msat: 0,
7784 unspendable_punishment_reserve: None,
7785 confirmations_required: None,
7786 confirmations: None,
7787 force_close_spend_delay: None,
7789 is_channel_ready: true,
7792 inbound_htlc_minimum_msat: None,
7793 inbound_htlc_maximum_msat: None,
7795 feerate_sat_per_1000_weight: None,
7796 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7800 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7801 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7802 starting_amount: u64, route_count: usize,
7803 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7804 let payer = payer_pubkey();
7805 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7806 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7808 let nodes = graph.read_only().nodes().clone();
7809 let mut route_endpoints = Vec::new();
7810 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7811 // with some routes we picked being un-routable.
7812 for _ in 0..route_count * 3 / 2 {
7814 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7815 let src = PublicKey::from_slice(nodes.unordered_keys()
7816 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7817 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7818 let dst = PublicKey::from_slice(nodes.unordered_keys()
7819 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7820 let params = PaymentParameters::from_node_id(dst, 42)
7821 .with_bolt11_features(features.clone()).unwrap();
7822 let first_hop = first_hop(src);
7823 let amt_msat = starting_amount + seed % 1_000_000;
7824 let route_params = RouteParameters::from_payment_params_and_value(
7825 params.clone(), amt_msat);
7827 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7828 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7830 // ...and seed the scorer with success and failure data...
7831 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7832 let mut score_amt = seed % 1_000_000_000;
7834 // Generate fail/success paths for a wider range of potential amounts with
7835 // MPP enabled to give us a chance to apply penalties for more potential
7837 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7838 let params = PaymentParameters::from_node_id(dst, 42)
7839 .with_bolt11_features(mpp_features).unwrap();
7840 let route_params = RouteParameters::from_payment_params_and_value(
7841 params.clone(), score_amt);
7842 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7843 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7844 &random_seed_bytes);
7845 if let Ok(route) = route_res {
7846 for path in route.paths {
7847 if seed & 0x80 == 0 {
7848 scorer.payment_path_successful(&path);
7850 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7851 scorer.payment_path_failed(&path, short_channel_id);
7853 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7857 // If we couldn't find a path with a higer amount, reduce and try again.
7861 route_endpoints.push((first_hop, params, amt_msat));
7867 // Because we've changed channel scores, it's possible we'll take different routes to the
7868 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7869 // requires a too-high CLTV delta.
7870 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7871 let route_params = RouteParameters::from_payment_params_and_value(
7872 params.clone(), *amt_msat);
7873 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7874 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7876 route_endpoints.truncate(route_count);
7877 assert_eq!(route_endpoints.len(), route_count);
7885 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7886 use crate::sign::{EntropySource, KeysManager};
7887 use crate::ln::channelmanager;
7888 use crate::ln::features::Bolt11InvoiceFeatures;
7889 use crate::routing::gossip::NetworkGraph;
7890 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7891 use crate::util::config::UserConfig;
7892 use crate::util::logger::{Logger, Record};
7893 use crate::util::test_utils::TestLogger;
7895 use criterion::Criterion;
7897 struct DummyLogger {}
7898 impl Logger for DummyLogger {
7899 fn log(&self, _record: &Record) {}
7902 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7903 let logger = TestLogger::new();
7904 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7905 let scorer = FixedPenaltyScorer::with_penalty(0);
7906 generate_routes(bench, &network_graph, scorer, &Default::default(),
7907 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
7910 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7911 let logger = TestLogger::new();
7912 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7913 let scorer = FixedPenaltyScorer::with_penalty(0);
7914 generate_routes(bench, &network_graph, scorer, &Default::default(),
7915 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7916 "generate_mpp_routes_with_zero_penalty_scorer");
7919 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7920 let logger = TestLogger::new();
7921 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7922 let params = ProbabilisticScoringFeeParameters::default();
7923 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7924 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7925 "generate_routes_with_probabilistic_scorer");
7928 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7929 let logger = TestLogger::new();
7930 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7931 let params = ProbabilisticScoringFeeParameters::default();
7932 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7933 generate_routes(bench, &network_graph, scorer, ¶ms,
7934 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7935 "generate_mpp_routes_with_probabilistic_scorer");
7938 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7939 let logger = TestLogger::new();
7940 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7941 let params = ProbabilisticScoringFeeParameters::default();
7942 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7943 generate_routes(bench, &network_graph, scorer, ¶ms,
7944 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7945 "generate_large_mpp_routes_with_probabilistic_scorer");
7948 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7949 let logger = TestLogger::new();
7950 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7951 let mut params = ProbabilisticScoringFeeParameters::default();
7952 params.linear_success_probability = false;
7953 let scorer = ProbabilisticScorer::new(
7954 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7955 generate_routes(bench, &network_graph, scorer, ¶ms,
7956 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7957 "generate_routes_with_nonlinear_probabilistic_scorer");
7960 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7961 let logger = TestLogger::new();
7962 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7963 let mut params = ProbabilisticScoringFeeParameters::default();
7964 params.linear_success_probability = false;
7965 let scorer = ProbabilisticScorer::new(
7966 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7967 generate_routes(bench, &network_graph, scorer, ¶ms,
7968 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7969 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
7972 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7973 let logger = TestLogger::new();
7974 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7975 let mut params = ProbabilisticScoringFeeParameters::default();
7976 params.linear_success_probability = false;
7977 let scorer = ProbabilisticScorer::new(
7978 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7979 generate_routes(bench, &network_graph, scorer, ¶ms,
7980 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7981 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
7984 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7985 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7986 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7987 bench_name: &'static str,
7989 let payer = bench_utils::payer_pubkey();
7990 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7991 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7993 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7994 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7996 // ...then benchmark finding paths between the nodes we learned.
7998 bench.bench_function(bench_name, |b| b.iter(|| {
7999 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8000 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8001 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8002 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());