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 already_collected_value_msat >= recommended_value_msat || !found_new_path {
2458 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2459 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2460 break 'paths_collection;
2461 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2462 // Further, if this was our first walk of the graph, and we weren't limited by an
2463 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2464 // limited by an htlc_minimum_msat value, find another path with a higher value,
2465 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2466 // still keeping a lower total fee than this path.
2467 if !hit_minimum_limit {
2468 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2469 break 'paths_collection;
2471 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.");
2472 path_value_msat = recommended_value_msat;
2476 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2477 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2478 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2479 num_ignored_total_fee_limit;
2480 if num_ignored_total > 0 {
2482 "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.",
2483 num_ignored_value_contribution, num_ignored_path_length_limit,
2484 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2485 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2486 num_ignored_total_fee_limit, num_ignored_total);
2490 if payment_paths.len() == 0 {
2491 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2494 if already_collected_value_msat < final_value_msat {
2495 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2499 let mut selected_route = payment_paths;
2501 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2502 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2504 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2505 // the value they contribute towards the payment amount.
2506 // We sort in descending order as we will remove from the front in `retain`, next.
2507 selected_route.sort_unstable_by(|a, b|
2508 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2509 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2512 // We should make sure that at least 1 path left.
2513 let mut paths_left = selected_route.len();
2514 selected_route.retain(|path| {
2515 if paths_left == 1 {
2518 let path_value_msat = path.get_value_msat();
2519 if path_value_msat <= overpaid_value_msat {
2520 overpaid_value_msat -= path_value_msat;
2526 debug_assert!(selected_route.len() > 0);
2528 if overpaid_value_msat != 0 {
2530 // Now, subtract the remaining overpaid value from the most-expensive path.
2531 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2532 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2533 selected_route.sort_unstable_by(|a, b| {
2534 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2535 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2536 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2538 let expensive_payment_path = selected_route.first_mut().unwrap();
2540 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2541 // can't go negative.
2542 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2543 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2547 // Sort by the path itself and combine redundant paths.
2548 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2549 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2551 selected_route.sort_unstable_by_key(|path| {
2552 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2553 debug_assert!(path.hops.len() <= key.len());
2554 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2559 for idx in 0..(selected_route.len() - 1) {
2560 if idx + 1 >= selected_route.len() { break; }
2561 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2562 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2563 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2564 selected_route[idx].update_value_and_recompute_fees(new_value);
2565 selected_route.remove(idx + 1);
2569 let mut paths = Vec::new();
2570 for payment_path in selected_route {
2571 let mut hops = Vec::with_capacity(payment_path.hops.len());
2572 let mut prev_hop_node_id = our_node_id;
2573 for (hop, node_features) in payment_path.hops.iter()
2574 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2576 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2577 // If we sourced the hop from the graph we're sure the target node is announced.
2579 } else if let CandidateRouteHop::FirstHop { details } = hop.candidate {
2580 // If this is a first hop we also know if it's announced.
2583 // If we sourced it any other way, we double-check the network graph to see if
2584 // there are announced channels between the endpoints. If so, the hop might be
2585 // referring to any of the announced channels, as its `short_channel_id` might be
2586 // an alias, in which case we don't take any chances here.
2587 network_graph.node(&hop.node_id).map_or(false, |hop_node|
2588 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2589 .map_or(false, |c| c.as_directed_from(&prev_hop_node_id).is_some()))
2593 hops.push(RouteHop {
2594 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)})?,
2595 node_features: node_features.clone(),
2596 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2597 channel_features: hop.candidate.features(),
2598 fee_msat: hop.fee_msat,
2599 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2600 maybe_announced_channel,
2603 prev_hop_node_id = hop.node_id;
2605 let mut final_cltv_delta = final_cltv_expiry_delta;
2606 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2607 if let Some(blinded_path) = h.candidate.blinded_path() {
2608 final_cltv_delta = h.candidate.cltv_expiry_delta();
2610 hops: blinded_path.blinded_hops.clone(),
2611 blinding_point: blinded_path.blinding_point,
2612 excess_final_cltv_expiry_delta: 0,
2613 final_value_msat: h.fee_msat,
2617 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2618 // applicable for the previous hop.
2619 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2620 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2623 paths.push(Path { hops, blinded_tail });
2625 // Make sure we would never create a route with more paths than we allow.
2626 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2628 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2629 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2630 if paths.iter().map(|p| p.fee_msat()).sum::<u64>() > max_total_routing_fee_msat {
2631 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2632 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2636 if let Some(node_features) = payment_params.payee.node_features() {
2637 for path in paths.iter_mut() {
2638 path.hops.last_mut().unwrap().node_features = node_features.clone();
2642 let route = Route { paths, route_params: Some(route_params.clone()) };
2643 log_info!(logger, "Got route: {}", log_route!(route));
2647 // When an adversarial intermediary node observes a payment, it may be able to infer its
2648 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2649 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2650 // payment path by adding a randomized 'shadow route' offset to the final hop.
2651 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2652 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2654 let network_channels = network_graph.channels();
2655 let network_nodes = network_graph.nodes();
2657 for path in route.paths.iter_mut() {
2658 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2660 // Remember the last three nodes of the random walk and avoid looping back on them.
2661 // Init with the last three nodes from the actual path, if possible.
2662 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2663 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2664 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2666 // Choose the last publicly known node as the starting point for the random walk.
2667 let mut cur_hop: Option<NodeId> = None;
2668 let mut path_nonce = [0u8; 12];
2669 if let Some(starting_hop) = path.hops.iter().rev()
2670 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2671 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2672 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2675 // Init PRNG with the path-dependant nonce, which is static for private paths.
2676 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2677 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2679 // Pick a random path length in [1 .. 3]
2680 prng.process_in_place(&mut random_path_bytes);
2681 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2683 for random_hop in 0..random_walk_length {
2684 // If we don't find a suitable offset in the public network graph, we default to
2685 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2686 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2688 if let Some(cur_node_id) = cur_hop {
2689 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2690 // Randomly choose the next unvisited hop.
2691 prng.process_in_place(&mut random_path_bytes);
2692 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2693 .checked_rem(cur_node.channels.len())
2694 .and_then(|index| cur_node.channels.get(index))
2695 .and_then(|id| network_channels.get(id)) {
2696 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2697 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2698 nodes_to_avoid[random_hop] = *next_id;
2699 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2700 cur_hop = Some(*next_id);
2707 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2708 .checked_add(random_hop_offset)
2709 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2712 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2713 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2714 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2716 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2717 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2718 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2719 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2720 max_path_offset = cmp::max(
2721 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2722 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2723 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2725 // Add 'shadow' CLTV offset to the final hop
2726 if let Some(tail) = path.blinded_tail.as_mut() {
2727 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2728 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2730 if let Some(last_hop) = path.hops.last_mut() {
2731 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2732 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2737 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2738 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2740 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2741 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2742 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2743 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2744 ) -> Result<Route, LightningError>
2745 where L::Target: Logger, GL::Target: Logger {
2746 let graph_lock = network_graph.read_only();
2747 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2748 &graph_lock, logger, random_seed_bytes)?;
2749 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2753 fn build_route_from_hops_internal<L: Deref>(
2754 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2755 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2756 ) -> Result<Route, LightningError> where L::Target: Logger {
2759 our_node_id: NodeId,
2760 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2763 impl ScoreLookUp for HopScorer {
2764 type ScoreParams = ();
2765 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2766 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2768 let mut cur_id = self.our_node_id;
2769 for i in 0..self.hop_ids.len() {
2770 if let Some(next_id) = self.hop_ids[i] {
2771 if cur_id == *source && next_id == *target {
2783 impl<'a> Writeable for HopScorer {
2785 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2790 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2791 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2794 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2795 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2796 for i in 0..hops.len() {
2797 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2800 let scorer = HopScorer { our_node_id, hop_ids };
2802 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
2807 use crate::blinded_path::{BlindedHop, BlindedPath};
2808 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2809 use crate::routing::utxo::UtxoResult;
2810 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2811 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2812 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2813 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2814 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2815 use crate::chain::transaction::OutPoint;
2816 use crate::sign::EntropySource;
2817 use crate::ln::ChannelId;
2818 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2819 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2820 use crate::ln::channelmanager;
2821 use crate::offers::invoice::BlindedPayInfo;
2822 use crate::util::config::UserConfig;
2823 use crate::util::test_utils as ln_test_utils;
2824 use crate::util::chacha20::ChaCha20;
2825 use crate::util::ser::{Readable, Writeable};
2827 use crate::util::ser::Writer;
2829 use bitcoin::hashes::Hash;
2830 use bitcoin::network::constants::Network;
2831 use bitcoin::blockdata::constants::genesis_block;
2832 use bitcoin::blockdata::script::Builder;
2833 use bitcoin::blockdata::opcodes;
2834 use bitcoin::blockdata::transaction::TxOut;
2838 use bitcoin::secp256k1::{PublicKey,SecretKey};
2839 use bitcoin::secp256k1::Secp256k1;
2841 use crate::io::Cursor;
2842 use crate::prelude::*;
2843 use crate::sync::Arc;
2845 use core::convert::TryInto;
2847 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2848 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2849 channelmanager::ChannelDetails {
2850 channel_id: ChannelId::new_zero(),
2851 counterparty: channelmanager::ChannelCounterparty {
2854 unspendable_punishment_reserve: 0,
2855 forwarding_info: None,
2856 outbound_htlc_minimum_msat: None,
2857 outbound_htlc_maximum_msat: None,
2859 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2862 outbound_scid_alias: None,
2863 inbound_scid_alias: None,
2864 channel_value_satoshis: 0,
2866 outbound_capacity_msat,
2867 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2868 next_outbound_htlc_minimum_msat: 0,
2869 inbound_capacity_msat: 42,
2870 unspendable_punishment_reserve: None,
2871 confirmations_required: None,
2872 confirmations: None,
2873 force_close_spend_delay: None,
2874 is_outbound: true, is_channel_ready: true,
2875 is_usable: true, is_public: true,
2876 inbound_htlc_minimum_msat: None,
2877 inbound_htlc_maximum_msat: None,
2879 feerate_sat_per_1000_weight: None,
2880 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2885 fn simple_route_test() {
2886 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2887 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2888 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2889 let scorer = ln_test_utils::TestScorer::new();
2890 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2891 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2893 // Simple route to 2 via 1
2895 let route_params = RouteParameters::from_payment_params_and_value(
2896 payment_params.clone(), 0);
2897 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2898 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
2899 &Default::default(), &random_seed_bytes) {
2900 assert_eq!(err, "Cannot send a payment of 0 msat");
2901 } else { panic!(); }
2903 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2904 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2905 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2906 assert_eq!(route.paths[0].hops.len(), 2);
2908 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2909 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2910 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2911 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2912 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2913 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2915 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2916 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2917 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2918 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2919 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2920 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2924 fn invalid_first_hop_test() {
2925 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2926 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2927 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2928 let scorer = ln_test_utils::TestScorer::new();
2929 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2930 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2932 // Simple route to 2 via 1
2934 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2936 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2937 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2938 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2939 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
2940 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2941 } else { panic!(); }
2943 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2944 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2945 assert_eq!(route.paths[0].hops.len(), 2);
2949 fn htlc_minimum_test() {
2950 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2951 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2952 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2953 let scorer = ln_test_utils::TestScorer::new();
2954 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2955 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2957 // Simple route to 2 via 1
2959 // Disable other paths
2960 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2962 short_channel_id: 12,
2964 flags: 2, // to disable
2965 cltv_expiry_delta: 0,
2966 htlc_minimum_msat: 0,
2967 htlc_maximum_msat: MAX_VALUE_MSAT,
2969 fee_proportional_millionths: 0,
2970 excess_data: Vec::new()
2972 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2974 short_channel_id: 3,
2976 flags: 2, // to disable
2977 cltv_expiry_delta: 0,
2978 htlc_minimum_msat: 0,
2979 htlc_maximum_msat: MAX_VALUE_MSAT,
2981 fee_proportional_millionths: 0,
2982 excess_data: Vec::new()
2984 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2985 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2986 short_channel_id: 13,
2988 flags: 2, // to disable
2989 cltv_expiry_delta: 0,
2990 htlc_minimum_msat: 0,
2991 htlc_maximum_msat: MAX_VALUE_MSAT,
2993 fee_proportional_millionths: 0,
2994 excess_data: Vec::new()
2996 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2997 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2998 short_channel_id: 6,
3000 flags: 2, // to disable
3001 cltv_expiry_delta: 0,
3002 htlc_minimum_msat: 0,
3003 htlc_maximum_msat: MAX_VALUE_MSAT,
3005 fee_proportional_millionths: 0,
3006 excess_data: Vec::new()
3008 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3009 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3010 short_channel_id: 7,
3012 flags: 2, // to disable
3013 cltv_expiry_delta: 0,
3014 htlc_minimum_msat: 0,
3015 htlc_maximum_msat: MAX_VALUE_MSAT,
3017 fee_proportional_millionths: 0,
3018 excess_data: Vec::new()
3021 // Check against amount_to_transfer_over_msat.
3022 // Set minimal HTLC of 200_000_000 msat.
3023 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3024 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3025 short_channel_id: 2,
3028 cltv_expiry_delta: 0,
3029 htlc_minimum_msat: 200_000_000,
3030 htlc_maximum_msat: MAX_VALUE_MSAT,
3032 fee_proportional_millionths: 0,
3033 excess_data: Vec::new()
3036 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3038 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3039 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3040 short_channel_id: 4,
3043 cltv_expiry_delta: 0,
3044 htlc_minimum_msat: 0,
3045 htlc_maximum_msat: 199_999_999,
3047 fee_proportional_millionths: 0,
3048 excess_data: Vec::new()
3051 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3052 let route_params = RouteParameters::from_payment_params_and_value(
3053 payment_params, 199_999_999);
3054 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3055 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3056 &Default::default(), &random_seed_bytes) {
3057 assert_eq!(err, "Failed to find a path to the given destination");
3058 } else { panic!(); }
3060 // Lift the restriction on the first hop.
3061 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3062 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3063 short_channel_id: 2,
3066 cltv_expiry_delta: 0,
3067 htlc_minimum_msat: 0,
3068 htlc_maximum_msat: MAX_VALUE_MSAT,
3070 fee_proportional_millionths: 0,
3071 excess_data: Vec::new()
3074 // A payment above the minimum should pass
3075 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3076 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3077 assert_eq!(route.paths[0].hops.len(), 2);
3081 fn htlc_minimum_overpay_test() {
3082 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3083 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3084 let config = UserConfig::default();
3085 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3086 let scorer = ln_test_utils::TestScorer::new();
3087 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3088 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3090 // A route to node#2 via two paths.
3091 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3092 // Thus, they can't send 60 without overpaying.
3093 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3094 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3095 short_channel_id: 2,
3098 cltv_expiry_delta: 0,
3099 htlc_minimum_msat: 35_000,
3100 htlc_maximum_msat: 40_000,
3102 fee_proportional_millionths: 0,
3103 excess_data: Vec::new()
3105 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3106 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3107 short_channel_id: 12,
3110 cltv_expiry_delta: 0,
3111 htlc_minimum_msat: 35_000,
3112 htlc_maximum_msat: 40_000,
3114 fee_proportional_millionths: 0,
3115 excess_data: Vec::new()
3119 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3120 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3121 short_channel_id: 13,
3124 cltv_expiry_delta: 0,
3125 htlc_minimum_msat: 0,
3126 htlc_maximum_msat: MAX_VALUE_MSAT,
3128 fee_proportional_millionths: 0,
3129 excess_data: Vec::new()
3131 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3132 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3133 short_channel_id: 4,
3136 cltv_expiry_delta: 0,
3137 htlc_minimum_msat: 0,
3138 htlc_maximum_msat: MAX_VALUE_MSAT,
3140 fee_proportional_millionths: 0,
3141 excess_data: Vec::new()
3144 // Disable other paths
3145 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3146 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3147 short_channel_id: 1,
3149 flags: 2, // to disable
3150 cltv_expiry_delta: 0,
3151 htlc_minimum_msat: 0,
3152 htlc_maximum_msat: MAX_VALUE_MSAT,
3154 fee_proportional_millionths: 0,
3155 excess_data: Vec::new()
3158 let mut route_params = RouteParameters::from_payment_params_and_value(
3159 payment_params.clone(), 60_000);
3160 route_params.max_total_routing_fee_msat = Some(15_000);
3161 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3162 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3163 // Overpay fees to hit htlc_minimum_msat.
3164 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3165 // TODO: this could be better balanced to overpay 10k and not 15k.
3166 assert_eq!(overpaid_fees, 15_000);
3168 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3169 // while taking even more fee to match htlc_minimum_msat.
3170 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3171 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3172 short_channel_id: 12,
3175 cltv_expiry_delta: 0,
3176 htlc_minimum_msat: 65_000,
3177 htlc_maximum_msat: 80_000,
3179 fee_proportional_millionths: 0,
3180 excess_data: Vec::new()
3182 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3183 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3184 short_channel_id: 2,
3187 cltv_expiry_delta: 0,
3188 htlc_minimum_msat: 0,
3189 htlc_maximum_msat: MAX_VALUE_MSAT,
3191 fee_proportional_millionths: 0,
3192 excess_data: Vec::new()
3194 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3195 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3196 short_channel_id: 4,
3199 cltv_expiry_delta: 0,
3200 htlc_minimum_msat: 0,
3201 htlc_maximum_msat: MAX_VALUE_MSAT,
3203 fee_proportional_millionths: 100_000,
3204 excess_data: Vec::new()
3207 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3208 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3209 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3210 assert_eq!(route.paths.len(), 1);
3211 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3212 let fees = route.paths[0].hops[0].fee_msat;
3213 assert_eq!(fees, 5_000);
3215 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3216 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3217 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3218 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3219 // the other channel.
3220 assert_eq!(route.paths.len(), 1);
3221 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3222 let fees = route.paths[0].hops[0].fee_msat;
3223 assert_eq!(fees, 5_000);
3227 fn disable_channels_test() {
3228 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3229 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3230 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3231 let scorer = ln_test_utils::TestScorer::new();
3232 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3233 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3235 // // Disable channels 4 and 12 by flags=2
3236 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3237 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3238 short_channel_id: 4,
3240 flags: 2, // to disable
3241 cltv_expiry_delta: 0,
3242 htlc_minimum_msat: 0,
3243 htlc_maximum_msat: MAX_VALUE_MSAT,
3245 fee_proportional_millionths: 0,
3246 excess_data: Vec::new()
3248 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3249 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3250 short_channel_id: 12,
3252 flags: 2, // to disable
3253 cltv_expiry_delta: 0,
3254 htlc_minimum_msat: 0,
3255 htlc_maximum_msat: MAX_VALUE_MSAT,
3257 fee_proportional_millionths: 0,
3258 excess_data: Vec::new()
3261 // If all the channels require some features we don't understand, route should fail
3262 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3263 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3264 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3265 &Default::default(), &random_seed_bytes) {
3266 assert_eq!(err, "Failed to find a path to the given destination");
3267 } else { panic!(); }
3269 // If we specify a channel to node7, that overrides our local channel view and that gets used
3270 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3271 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3272 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3273 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3274 &Default::default(), &random_seed_bytes).unwrap();
3275 assert_eq!(route.paths[0].hops.len(), 2);
3277 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3278 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3279 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3280 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3281 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3282 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3284 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3285 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3286 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3287 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3288 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3289 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3293 fn disable_node_test() {
3294 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3295 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3296 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3297 let scorer = ln_test_utils::TestScorer::new();
3298 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3299 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3301 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3302 let mut unknown_features = NodeFeatures::empty();
3303 unknown_features.set_unknown_feature_required();
3304 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3305 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3306 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3308 // If all nodes require some features we don't understand, route should fail
3309 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3310 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3311 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3312 &Default::default(), &random_seed_bytes) {
3313 assert_eq!(err, "Failed to find a path to the given destination");
3314 } else { panic!(); }
3316 // If we specify a channel to node7, that overrides our local channel view and that gets used
3317 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3318 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3319 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3320 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3321 &Default::default(), &random_seed_bytes).unwrap();
3322 assert_eq!(route.paths[0].hops.len(), 2);
3324 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3325 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3326 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3327 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3328 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3329 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3331 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3332 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3333 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3334 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3335 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3336 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3338 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3339 // naively) assume that the user checked the feature bits on the invoice, which override
3340 // the node_announcement.
3344 fn our_chans_test() {
3345 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3346 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3347 let scorer = ln_test_utils::TestScorer::new();
3348 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3349 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3351 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3352 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3353 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3354 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3355 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3356 assert_eq!(route.paths[0].hops.len(), 3);
3358 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3359 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3360 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3361 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3362 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3363 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3365 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3366 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3367 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3368 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3369 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3370 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3372 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3373 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3374 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3375 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3376 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3377 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3379 // If we specify a channel to node7, that overrides our local channel view and that gets used
3380 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3381 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
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]);
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));
3404 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3405 let zero_fees = RoutingFees {
3407 proportional_millionths: 0,
3409 vec![RouteHint(vec![RouteHintHop {
3410 src_node_id: nodes[3],
3411 short_channel_id: 8,
3413 cltv_expiry_delta: (8 << 4) | 1,
3414 htlc_minimum_msat: None,
3415 htlc_maximum_msat: None,
3417 ]), RouteHint(vec![RouteHintHop {
3418 src_node_id: nodes[4],
3419 short_channel_id: 9,
3422 proportional_millionths: 0,
3424 cltv_expiry_delta: (9 << 4) | 1,
3425 htlc_minimum_msat: None,
3426 htlc_maximum_msat: None,
3427 }]), RouteHint(vec![RouteHintHop {
3428 src_node_id: nodes[5],
3429 short_channel_id: 10,
3431 cltv_expiry_delta: (10 << 4) | 1,
3432 htlc_minimum_msat: None,
3433 htlc_maximum_msat: None,
3437 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3438 let zero_fees = RoutingFees {
3440 proportional_millionths: 0,
3442 vec![RouteHint(vec![RouteHintHop {
3443 src_node_id: nodes[2],
3444 short_channel_id: 5,
3447 proportional_millionths: 0,
3449 cltv_expiry_delta: (5 << 4) | 1,
3450 htlc_minimum_msat: None,
3451 htlc_maximum_msat: None,
3453 src_node_id: nodes[3],
3454 short_channel_id: 8,
3456 cltv_expiry_delta: (8 << 4) | 1,
3457 htlc_minimum_msat: None,
3458 htlc_maximum_msat: None,
3460 ]), RouteHint(vec![RouteHintHop {
3461 src_node_id: nodes[4],
3462 short_channel_id: 9,
3465 proportional_millionths: 0,
3467 cltv_expiry_delta: (9 << 4) | 1,
3468 htlc_minimum_msat: None,
3469 htlc_maximum_msat: None,
3470 }]), RouteHint(vec![RouteHintHop {
3471 src_node_id: nodes[5],
3472 short_channel_id: 10,
3474 cltv_expiry_delta: (10 << 4) | 1,
3475 htlc_minimum_msat: None,
3476 htlc_maximum_msat: None,
3481 fn partial_route_hint_test() {
3482 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3483 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3484 let scorer = ln_test_utils::TestScorer::new();
3485 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3486 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3488 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3489 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3490 // RouteHint may be partially used by the algo to build the best path.
3492 // First check that last hop can't have its source as the payee.
3493 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3494 src_node_id: nodes[6],
3495 short_channel_id: 8,
3498 proportional_millionths: 0,
3500 cltv_expiry_delta: (8 << 4) | 1,
3501 htlc_minimum_msat: None,
3502 htlc_maximum_msat: None,
3505 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3506 invalid_last_hops.push(invalid_last_hop);
3508 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3509 .with_route_hints(invalid_last_hops).unwrap();
3510 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3511 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3512 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3513 &Default::default(), &random_seed_bytes) {
3514 assert_eq!(err, "Route hint cannot have the payee as the source.");
3515 } else { panic!(); }
3518 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3519 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3520 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3521 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3522 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3523 assert_eq!(route.paths[0].hops.len(), 5);
3525 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3526 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3527 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3528 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3529 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3530 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3532 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3533 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3534 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3535 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3536 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3537 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3539 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3540 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3541 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3542 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3543 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3544 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3546 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3547 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3548 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3549 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3550 // If we have a peer in the node map, we'll use their features here since we don't have
3551 // a way of figuring out their features from the invoice:
3552 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3553 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3555 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3556 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3557 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3558 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3559 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3560 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3563 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3564 let zero_fees = RoutingFees {
3566 proportional_millionths: 0,
3568 vec![RouteHint(vec![RouteHintHop {
3569 src_node_id: nodes[3],
3570 short_channel_id: 8,
3572 cltv_expiry_delta: (8 << 4) | 1,
3573 htlc_minimum_msat: None,
3574 htlc_maximum_msat: None,
3575 }]), RouteHint(vec![
3577 ]), RouteHint(vec![RouteHintHop {
3578 src_node_id: nodes[5],
3579 short_channel_id: 10,
3581 cltv_expiry_delta: (10 << 4) | 1,
3582 htlc_minimum_msat: None,
3583 htlc_maximum_msat: None,
3588 fn ignores_empty_last_hops_test() {
3589 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3590 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3591 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3592 let scorer = ln_test_utils::TestScorer::new();
3593 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3594 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3596 // Test handling of an empty RouteHint passed in Invoice.
3597 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3598 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3599 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3600 assert_eq!(route.paths[0].hops.len(), 5);
3602 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3603 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3604 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3605 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3606 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3607 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3609 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3610 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3611 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3612 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3613 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3614 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3616 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3617 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3618 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3619 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3620 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3621 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3623 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3624 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3625 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3626 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3627 // If we have a peer in the node map, we'll use their features here since we don't have
3628 // a way of figuring out their features from the invoice:
3629 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3630 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3632 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3633 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3634 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3635 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3636 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3637 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3640 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3642 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3643 let zero_fees = RoutingFees {
3645 proportional_millionths: 0,
3647 vec![RouteHint(vec![RouteHintHop {
3648 src_node_id: hint_hops[0],
3649 short_channel_id: 0xff00,
3652 proportional_millionths: 0,
3654 cltv_expiry_delta: (5 << 4) | 1,
3655 htlc_minimum_msat: None,
3656 htlc_maximum_msat: None,
3658 src_node_id: hint_hops[1],
3659 short_channel_id: 0xff01,
3661 cltv_expiry_delta: (8 << 4) | 1,
3662 htlc_minimum_msat: None,
3663 htlc_maximum_msat: None,
3668 fn multi_hint_last_hops_test() {
3669 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3670 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3671 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3672 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3673 let scorer = ln_test_utils::TestScorer::new();
3674 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3675 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3676 // Test through channels 2, 3, 0xff00, 0xff01.
3677 // Test shows that multiple hop hints are considered.
3679 // Disabling channels 6 & 7 by flags=2
3680 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3681 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3682 short_channel_id: 6,
3684 flags: 2, // to disable
3685 cltv_expiry_delta: 0,
3686 htlc_minimum_msat: 0,
3687 htlc_maximum_msat: MAX_VALUE_MSAT,
3689 fee_proportional_millionths: 0,
3690 excess_data: Vec::new()
3692 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3693 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3694 short_channel_id: 7,
3696 flags: 2, // to disable
3697 cltv_expiry_delta: 0,
3698 htlc_minimum_msat: 0,
3699 htlc_maximum_msat: MAX_VALUE_MSAT,
3701 fee_proportional_millionths: 0,
3702 excess_data: Vec::new()
3705 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3706 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3707 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3708 assert_eq!(route.paths[0].hops.len(), 4);
3710 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3711 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3712 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3713 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3714 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3715 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3717 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3718 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3719 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3720 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3721 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3722 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3724 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3725 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3726 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3727 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3728 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3729 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3731 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3732 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3733 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3734 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3735 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3736 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3740 fn private_multi_hint_last_hops_test() {
3741 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3742 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3744 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3745 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3747 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3748 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3749 let scorer = ln_test_utils::TestScorer::new();
3750 // Test through channels 2, 3, 0xff00, 0xff01.
3751 // Test shows that multiple hop hints are considered.
3753 // Disabling channels 6 & 7 by flags=2
3754 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3755 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3756 short_channel_id: 6,
3758 flags: 2, // to disable
3759 cltv_expiry_delta: 0,
3760 htlc_minimum_msat: 0,
3761 htlc_maximum_msat: MAX_VALUE_MSAT,
3763 fee_proportional_millionths: 0,
3764 excess_data: Vec::new()
3766 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3767 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3768 short_channel_id: 7,
3770 flags: 2, // to disable
3771 cltv_expiry_delta: 0,
3772 htlc_minimum_msat: 0,
3773 htlc_maximum_msat: MAX_VALUE_MSAT,
3775 fee_proportional_millionths: 0,
3776 excess_data: Vec::new()
3779 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3780 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3781 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
3782 assert_eq!(route.paths[0].hops.len(), 4);
3784 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3785 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3786 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3787 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3788 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3789 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3791 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3792 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3793 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3794 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3795 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3796 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3798 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3799 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3800 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3801 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3802 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3803 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3805 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3806 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3807 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3808 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3809 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3810 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3813 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3814 let zero_fees = RoutingFees {
3816 proportional_millionths: 0,
3818 vec![RouteHint(vec![RouteHintHop {
3819 src_node_id: nodes[4],
3820 short_channel_id: 11,
3822 cltv_expiry_delta: (11 << 4) | 1,
3823 htlc_minimum_msat: None,
3824 htlc_maximum_msat: None,
3826 src_node_id: nodes[3],
3827 short_channel_id: 8,
3829 cltv_expiry_delta: (8 << 4) | 1,
3830 htlc_minimum_msat: None,
3831 htlc_maximum_msat: None,
3832 }]), RouteHint(vec![RouteHintHop {
3833 src_node_id: nodes[4],
3834 short_channel_id: 9,
3837 proportional_millionths: 0,
3839 cltv_expiry_delta: (9 << 4) | 1,
3840 htlc_minimum_msat: None,
3841 htlc_maximum_msat: None,
3842 }]), RouteHint(vec![RouteHintHop {
3843 src_node_id: nodes[5],
3844 short_channel_id: 10,
3846 cltv_expiry_delta: (10 << 4) | 1,
3847 htlc_minimum_msat: None,
3848 htlc_maximum_msat: None,
3853 fn last_hops_with_public_channel_test() {
3854 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3855 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3856 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3857 let scorer = ln_test_utils::TestScorer::new();
3858 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3859 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3860 // This test shows that public routes can be present in the invoice
3861 // which would be handled in the same manner.
3863 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3864 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3865 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3866 assert_eq!(route.paths[0].hops.len(), 5);
3868 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3869 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3870 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3871 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3872 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3873 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3875 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3876 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3877 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3878 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3879 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3880 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3882 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3883 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3884 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3885 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3886 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3887 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3889 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3890 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3891 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3892 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3893 // If we have a peer in the node map, we'll use their features here since we don't have
3894 // a way of figuring out their features from the invoice:
3895 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3896 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3898 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3899 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3900 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3901 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3902 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3903 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3907 fn our_chans_last_hop_connect_test() {
3908 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3909 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3910 let scorer = ln_test_utils::TestScorer::new();
3911 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3912 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3914 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3915 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3916 let mut last_hops = last_hops(&nodes);
3917 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3918 .with_route_hints(last_hops.clone()).unwrap();
3919 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3920 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3921 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3922 &Default::default(), &random_seed_bytes).unwrap();
3923 assert_eq!(route.paths[0].hops.len(), 2);
3925 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3926 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3927 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3928 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3929 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3930 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3932 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3933 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3934 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3935 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3936 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3937 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3939 last_hops[0].0[0].fees.base_msat = 1000;
3941 // Revert to via 6 as the fee on 8 goes up
3942 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3943 .with_route_hints(last_hops).unwrap();
3944 let route_params = RouteParameters::from_payment_params_and_value(
3945 payment_params.clone(), 100);
3946 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3947 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3948 assert_eq!(route.paths[0].hops.len(), 4);
3950 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3951 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3952 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3953 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3954 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3955 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3957 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3958 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3959 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3960 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3961 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3962 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3964 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3965 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3966 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3967 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3968 // If we have a peer in the node map, we'll use their features here since we don't have
3969 // a way of figuring out their features from the invoice:
3970 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3971 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3973 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3974 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3975 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3976 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3977 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3978 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3980 // ...but still use 8 for larger payments as 6 has a variable feerate
3981 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
3982 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3983 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3984 assert_eq!(route.paths[0].hops.len(), 5);
3986 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3987 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3988 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3989 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3990 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3991 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3993 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3994 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3995 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3996 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3997 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3998 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4000 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4001 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4002 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4003 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4004 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4005 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4007 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4008 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4009 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4010 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4011 // If we have a peer in the node map, we'll use their features here since we don't have
4012 // a way of figuring out their features from the invoice:
4013 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4014 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4016 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4017 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4018 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4019 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4020 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4021 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4024 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> {
4025 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4026 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4027 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4029 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4030 let last_hops = RouteHint(vec![RouteHintHop {
4031 src_node_id: middle_node_id,
4032 short_channel_id: 8,
4035 proportional_millionths: last_hop_fee_prop,
4037 cltv_expiry_delta: (8 << 4) | 1,
4038 htlc_minimum_msat: None,
4039 htlc_maximum_msat: last_hop_htlc_max,
4041 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4042 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4043 let scorer = ln_test_utils::TestScorer::new();
4044 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4045 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4046 let logger = ln_test_utils::TestLogger::new();
4047 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4048 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4049 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4050 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4051 &random_seed_bytes);
4056 fn unannounced_path_test() {
4057 // We should be able to send a payment to a destination without any help of a routing graph
4058 // if we have a channel with a common counterparty that appears in the first and last hop
4060 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4062 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4063 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4064 assert_eq!(route.paths[0].hops.len(), 2);
4066 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4067 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4068 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4069 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4070 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4071 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4073 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4074 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4075 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4076 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4077 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4078 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4082 fn overflow_unannounced_path_test_liquidity_underflow() {
4083 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4084 // the last-hop had a fee which overflowed a u64, we'd panic.
4085 // This was due to us adding the first-hop from us unconditionally, causing us to think
4086 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4087 // In this test, we previously hit a subtraction underflow due to having less available
4088 // liquidity at the last hop than 0.
4089 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());
4093 fn overflow_unannounced_path_test_feerate_overflow() {
4094 // This tests for the same case as above, except instead of hitting a subtraction
4095 // underflow, we hit a case where the fee charged at a hop overflowed.
4096 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());
4100 fn available_amount_while_routing_test() {
4101 // Tests whether we choose the correct available channel amount while routing.
4103 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4104 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4105 let scorer = ln_test_utils::TestScorer::new();
4106 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4107 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4108 let config = UserConfig::default();
4109 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4111 // We will use a simple single-path route from
4112 // our node to node2 via node0: channels {1, 3}.
4114 // First disable all other paths.
4115 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4116 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4117 short_channel_id: 2,
4120 cltv_expiry_delta: 0,
4121 htlc_minimum_msat: 0,
4122 htlc_maximum_msat: 100_000,
4124 fee_proportional_millionths: 0,
4125 excess_data: Vec::new()
4127 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4128 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4129 short_channel_id: 12,
4132 cltv_expiry_delta: 0,
4133 htlc_minimum_msat: 0,
4134 htlc_maximum_msat: 100_000,
4136 fee_proportional_millionths: 0,
4137 excess_data: Vec::new()
4140 // Make the first channel (#1) very permissive,
4141 // and we will be testing all limits on the second channel.
4142 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4144 short_channel_id: 1,
4147 cltv_expiry_delta: 0,
4148 htlc_minimum_msat: 0,
4149 htlc_maximum_msat: 1_000_000_000,
4151 fee_proportional_millionths: 0,
4152 excess_data: Vec::new()
4155 // First, let's see if routing works if we have absolutely no idea about the available amount.
4156 // In this case, it should be set to 250_000 sats.
4157 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4158 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4159 short_channel_id: 3,
4162 cltv_expiry_delta: 0,
4163 htlc_minimum_msat: 0,
4164 htlc_maximum_msat: 250_000_000,
4166 fee_proportional_millionths: 0,
4167 excess_data: Vec::new()
4171 // Attempt to route more than available results in a failure.
4172 let route_params = RouteParameters::from_payment_params_and_value(
4173 payment_params.clone(), 250_000_001);
4174 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4175 &our_id, &route_params, &network_graph.read_only(), None,
4176 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4177 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4178 } else { panic!(); }
4182 // Now, attempt to route an exact amount we have should be fine.
4183 let route_params = RouteParameters::from_payment_params_and_value(
4184 payment_params.clone(), 250_000_000);
4185 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4186 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4187 assert_eq!(route.paths.len(), 1);
4188 let path = route.paths.last().unwrap();
4189 assert_eq!(path.hops.len(), 2);
4190 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4191 assert_eq!(path.final_value_msat(), 250_000_000);
4194 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4195 // Disable channel #1 and use another first hop.
4196 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4197 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4198 short_channel_id: 1,
4201 cltv_expiry_delta: 0,
4202 htlc_minimum_msat: 0,
4203 htlc_maximum_msat: 1_000_000_000,
4205 fee_proportional_millionths: 0,
4206 excess_data: Vec::new()
4209 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4210 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4213 // Attempt to route more than available results in a failure.
4214 let route_params = RouteParameters::from_payment_params_and_value(
4215 payment_params.clone(), 200_000_001);
4216 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4217 &our_id, &route_params, &network_graph.read_only(),
4218 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4219 &Default::default(), &random_seed_bytes) {
4220 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4221 } else { panic!(); }
4225 // Now, attempt to route an exact amount we have should be fine.
4226 let route_params = RouteParameters::from_payment_params_and_value(
4227 payment_params.clone(), 200_000_000);
4228 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4229 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4230 &Default::default(), &random_seed_bytes).unwrap();
4231 assert_eq!(route.paths.len(), 1);
4232 let path = route.paths.last().unwrap();
4233 assert_eq!(path.hops.len(), 2);
4234 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4235 assert_eq!(path.final_value_msat(), 200_000_000);
4238 // Enable channel #1 back.
4239 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4240 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4241 short_channel_id: 1,
4244 cltv_expiry_delta: 0,
4245 htlc_minimum_msat: 0,
4246 htlc_maximum_msat: 1_000_000_000,
4248 fee_proportional_millionths: 0,
4249 excess_data: Vec::new()
4253 // Now let's see if routing works if we know only htlc_maximum_msat.
4254 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4255 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4256 short_channel_id: 3,
4259 cltv_expiry_delta: 0,
4260 htlc_minimum_msat: 0,
4261 htlc_maximum_msat: 15_000,
4263 fee_proportional_millionths: 0,
4264 excess_data: Vec::new()
4268 // Attempt to route more than available results in a failure.
4269 let route_params = RouteParameters::from_payment_params_and_value(
4270 payment_params.clone(), 15_001);
4271 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4272 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4273 &scorer, &Default::default(), &random_seed_bytes) {
4274 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4275 } else { panic!(); }
4279 // Now, attempt to route an exact amount we have should be fine.
4280 let route_params = RouteParameters::from_payment_params_and_value(
4281 payment_params.clone(), 15_000);
4282 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4283 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4284 assert_eq!(route.paths.len(), 1);
4285 let path = route.paths.last().unwrap();
4286 assert_eq!(path.hops.len(), 2);
4287 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4288 assert_eq!(path.final_value_msat(), 15_000);
4291 // Now let's see if routing works if we know only capacity from the UTXO.
4293 // We can't change UTXO capacity on the fly, so we'll disable
4294 // the existing channel and add another one with the capacity we need.
4295 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4296 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4297 short_channel_id: 3,
4300 cltv_expiry_delta: 0,
4301 htlc_minimum_msat: 0,
4302 htlc_maximum_msat: MAX_VALUE_MSAT,
4304 fee_proportional_millionths: 0,
4305 excess_data: Vec::new()
4308 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4309 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4310 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4311 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4312 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4314 *chain_monitor.utxo_ret.lock().unwrap() =
4315 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4316 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4318 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4319 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4320 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4321 short_channel_id: 333,
4324 cltv_expiry_delta: (3 << 4) | 1,
4325 htlc_minimum_msat: 0,
4326 htlc_maximum_msat: 15_000,
4328 fee_proportional_millionths: 0,
4329 excess_data: Vec::new()
4331 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4332 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4333 short_channel_id: 333,
4336 cltv_expiry_delta: (3 << 4) | 2,
4337 htlc_minimum_msat: 0,
4338 htlc_maximum_msat: 15_000,
4340 fee_proportional_millionths: 0,
4341 excess_data: Vec::new()
4345 // Attempt to route more than available results in a failure.
4346 let route_params = RouteParameters::from_payment_params_and_value(
4347 payment_params.clone(), 15_001);
4348 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4349 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4350 &scorer, &Default::default(), &random_seed_bytes) {
4351 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4352 } else { panic!(); }
4356 // Now, attempt to route an exact amount we have should be fine.
4357 let route_params = RouteParameters::from_payment_params_and_value(
4358 payment_params.clone(), 15_000);
4359 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4360 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4361 assert_eq!(route.paths.len(), 1);
4362 let path = route.paths.last().unwrap();
4363 assert_eq!(path.hops.len(), 2);
4364 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4365 assert_eq!(path.final_value_msat(), 15_000);
4368 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4369 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4370 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4371 short_channel_id: 333,
4374 cltv_expiry_delta: 0,
4375 htlc_minimum_msat: 0,
4376 htlc_maximum_msat: 10_000,
4378 fee_proportional_millionths: 0,
4379 excess_data: Vec::new()
4383 // Attempt to route more than available results in a failure.
4384 let route_params = RouteParameters::from_payment_params_and_value(
4385 payment_params.clone(), 10_001);
4386 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4387 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4388 &scorer, &Default::default(), &random_seed_bytes) {
4389 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4390 } else { panic!(); }
4394 // Now, attempt to route an exact amount we have should be fine.
4395 let route_params = RouteParameters::from_payment_params_and_value(
4396 payment_params.clone(), 10_000);
4397 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4398 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4399 assert_eq!(route.paths.len(), 1);
4400 let path = route.paths.last().unwrap();
4401 assert_eq!(path.hops.len(), 2);
4402 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4403 assert_eq!(path.final_value_msat(), 10_000);
4408 fn available_liquidity_last_hop_test() {
4409 // Check that available liquidity properly limits the path even when only
4410 // one of the latter hops is limited.
4411 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4412 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4413 let scorer = ln_test_utils::TestScorer::new();
4414 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4415 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4416 let config = UserConfig::default();
4417 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4419 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4420 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4421 // Total capacity: 50 sats.
4423 // Disable other potential paths.
4424 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4425 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4426 short_channel_id: 2,
4429 cltv_expiry_delta: 0,
4430 htlc_minimum_msat: 0,
4431 htlc_maximum_msat: 100_000,
4433 fee_proportional_millionths: 0,
4434 excess_data: Vec::new()
4436 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4437 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4438 short_channel_id: 7,
4441 cltv_expiry_delta: 0,
4442 htlc_minimum_msat: 0,
4443 htlc_maximum_msat: 100_000,
4445 fee_proportional_millionths: 0,
4446 excess_data: Vec::new()
4451 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4452 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4453 short_channel_id: 12,
4456 cltv_expiry_delta: 0,
4457 htlc_minimum_msat: 0,
4458 htlc_maximum_msat: 100_000,
4460 fee_proportional_millionths: 0,
4461 excess_data: Vec::new()
4463 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4464 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4465 short_channel_id: 13,
4468 cltv_expiry_delta: 0,
4469 htlc_minimum_msat: 0,
4470 htlc_maximum_msat: 100_000,
4472 fee_proportional_millionths: 0,
4473 excess_data: Vec::new()
4476 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4477 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4478 short_channel_id: 6,
4481 cltv_expiry_delta: 0,
4482 htlc_minimum_msat: 0,
4483 htlc_maximum_msat: 50_000,
4485 fee_proportional_millionths: 0,
4486 excess_data: Vec::new()
4488 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4489 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4490 short_channel_id: 11,
4493 cltv_expiry_delta: 0,
4494 htlc_minimum_msat: 0,
4495 htlc_maximum_msat: 100_000,
4497 fee_proportional_millionths: 0,
4498 excess_data: Vec::new()
4501 // Attempt to route more than available results in a failure.
4502 let route_params = RouteParameters::from_payment_params_and_value(
4503 payment_params.clone(), 60_000);
4504 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4505 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4506 &scorer, &Default::default(), &random_seed_bytes) {
4507 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4508 } else { panic!(); }
4512 // Now, attempt to route 49 sats (just a bit below the capacity).
4513 let route_params = RouteParameters::from_payment_params_and_value(
4514 payment_params.clone(), 49_000);
4515 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4516 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4517 assert_eq!(route.paths.len(), 1);
4518 let mut total_amount_paid_msat = 0;
4519 for path in &route.paths {
4520 assert_eq!(path.hops.len(), 4);
4521 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4522 total_amount_paid_msat += path.final_value_msat();
4524 assert_eq!(total_amount_paid_msat, 49_000);
4528 // Attempt to route an exact amount is also fine
4529 let route_params = RouteParameters::from_payment_params_and_value(
4530 payment_params, 50_000);
4531 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4532 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4533 assert_eq!(route.paths.len(), 1);
4534 let mut total_amount_paid_msat = 0;
4535 for path in &route.paths {
4536 assert_eq!(path.hops.len(), 4);
4537 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4538 total_amount_paid_msat += path.final_value_msat();
4540 assert_eq!(total_amount_paid_msat, 50_000);
4545 fn ignore_fee_first_hop_test() {
4546 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4547 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4548 let scorer = ln_test_utils::TestScorer::new();
4549 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4550 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4551 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4553 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4554 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4555 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4556 short_channel_id: 1,
4559 cltv_expiry_delta: 0,
4560 htlc_minimum_msat: 0,
4561 htlc_maximum_msat: 100_000,
4562 fee_base_msat: 1_000_000,
4563 fee_proportional_millionths: 0,
4564 excess_data: Vec::new()
4566 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4567 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4568 short_channel_id: 3,
4571 cltv_expiry_delta: 0,
4572 htlc_minimum_msat: 0,
4573 htlc_maximum_msat: 50_000,
4575 fee_proportional_millionths: 0,
4576 excess_data: Vec::new()
4580 let route_params = RouteParameters::from_payment_params_and_value(
4581 payment_params, 50_000);
4582 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4583 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4584 assert_eq!(route.paths.len(), 1);
4585 let mut total_amount_paid_msat = 0;
4586 for path in &route.paths {
4587 assert_eq!(path.hops.len(), 2);
4588 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4589 total_amount_paid_msat += path.final_value_msat();
4591 assert_eq!(total_amount_paid_msat, 50_000);
4596 fn simple_mpp_route_test() {
4597 let (secp_ctx, _, _, _, _) = build_graph();
4598 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4599 let config = UserConfig::default();
4600 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4601 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4602 do_simple_mpp_route_test(clear_payment_params);
4604 // MPP to a 1-hop blinded path for nodes[2]
4605 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4606 let blinded_path = BlindedPath {
4607 introduction_node_id: nodes[2],
4608 blinding_point: ln_test_utils::pubkey(42),
4609 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4611 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4613 fee_proportional_millionths: 0,
4614 htlc_minimum_msat: 0,
4615 htlc_maximum_msat: 0,
4616 cltv_expiry_delta: 0,
4617 features: BlindedHopFeatures::empty(),
4619 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4620 .with_bolt12_features(bolt12_features.clone()).unwrap();
4621 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4623 // MPP to 3 2-hop blinded paths
4624 let mut blinded_path_node_0 = blinded_path.clone();
4625 blinded_path_node_0.introduction_node_id = nodes[0];
4626 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4627 let mut node_0_payinfo = blinded_payinfo.clone();
4628 node_0_payinfo.htlc_maximum_msat = 50_000;
4630 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4631 blinded_path_node_7.introduction_node_id = nodes[7];
4632 let mut node_7_payinfo = blinded_payinfo.clone();
4633 node_7_payinfo.htlc_maximum_msat = 60_000;
4635 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4636 blinded_path_node_1.introduction_node_id = nodes[1];
4637 let mut node_1_payinfo = blinded_payinfo.clone();
4638 node_1_payinfo.htlc_maximum_msat = 180_000;
4640 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4642 (node_0_payinfo, blinded_path_node_0),
4643 (node_7_payinfo, blinded_path_node_7),
4644 (node_1_payinfo, blinded_path_node_1)
4646 .with_bolt12_features(bolt12_features).unwrap();
4647 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4651 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4652 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4653 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4654 let scorer = ln_test_utils::TestScorer::new();
4655 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4656 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4658 // We need a route consisting of 3 paths:
4659 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4660 // To achieve this, the amount being transferred should be around
4661 // the total capacity of these 3 paths.
4663 // First, we set limits on these (previously unlimited) channels.
4664 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4666 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4667 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4668 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4669 short_channel_id: 1,
4672 cltv_expiry_delta: 0,
4673 htlc_minimum_msat: 0,
4674 htlc_maximum_msat: 100_000,
4676 fee_proportional_millionths: 0,
4677 excess_data: Vec::new()
4679 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4680 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4681 short_channel_id: 3,
4684 cltv_expiry_delta: 0,
4685 htlc_minimum_msat: 0,
4686 htlc_maximum_msat: 50_000,
4688 fee_proportional_millionths: 0,
4689 excess_data: Vec::new()
4692 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4693 // (total limit 60).
4694 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4695 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4696 short_channel_id: 12,
4699 cltv_expiry_delta: 0,
4700 htlc_minimum_msat: 0,
4701 htlc_maximum_msat: 60_000,
4703 fee_proportional_millionths: 0,
4704 excess_data: Vec::new()
4706 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4707 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4708 short_channel_id: 13,
4711 cltv_expiry_delta: 0,
4712 htlc_minimum_msat: 0,
4713 htlc_maximum_msat: 60_000,
4715 fee_proportional_millionths: 0,
4716 excess_data: Vec::new()
4719 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4720 // (total capacity 180 sats).
4721 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4722 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4723 short_channel_id: 2,
4726 cltv_expiry_delta: 0,
4727 htlc_minimum_msat: 0,
4728 htlc_maximum_msat: 200_000,
4730 fee_proportional_millionths: 0,
4731 excess_data: Vec::new()
4733 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4734 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4735 short_channel_id: 4,
4738 cltv_expiry_delta: 0,
4739 htlc_minimum_msat: 0,
4740 htlc_maximum_msat: 180_000,
4742 fee_proportional_millionths: 0,
4743 excess_data: Vec::new()
4747 // Attempt to route more than available results in a failure.
4748 let route_params = RouteParameters::from_payment_params_and_value(
4749 payment_params.clone(), 300_000);
4750 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4751 &our_id, &route_params, &network_graph.read_only(), None,
4752 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4753 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4754 } else { panic!(); }
4758 // Attempt to route while setting max_path_count to 0 results in a failure.
4759 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4760 let route_params = RouteParameters::from_payment_params_and_value(
4761 zero_payment_params, 100);
4762 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4763 &our_id, &route_params, &network_graph.read_only(), None,
4764 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4765 assert_eq!(err, "Can't find a route with no paths allowed.");
4766 } else { panic!(); }
4770 // Attempt to route while setting max_path_count to 3 results in a failure.
4771 // This is the case because the minimal_value_contribution_msat would require each path
4772 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4773 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4774 let route_params = RouteParameters::from_payment_params_and_value(
4775 fail_payment_params, 250_000);
4776 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4777 &our_id, &route_params, &network_graph.read_only(), None,
4778 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4779 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4780 } else { panic!(); }
4784 // Now, attempt to route 250 sats (just a bit below the capacity).
4785 // Our algorithm should provide us with these 3 paths.
4786 let route_params = RouteParameters::from_payment_params_and_value(
4787 payment_params.clone(), 250_000);
4788 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4789 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4790 assert_eq!(route.paths.len(), 3);
4791 let mut total_amount_paid_msat = 0;
4792 for path in &route.paths {
4793 if let Some(bt) = &path.blinded_tail {
4794 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4796 assert_eq!(path.hops.len(), 2);
4797 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4799 total_amount_paid_msat += path.final_value_msat();
4801 assert_eq!(total_amount_paid_msat, 250_000);
4805 // Attempt to route an exact amount is also fine
4806 let route_params = RouteParameters::from_payment_params_and_value(
4807 payment_params.clone(), 290_000);
4808 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4809 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4810 assert_eq!(route.paths.len(), 3);
4811 let mut total_amount_paid_msat = 0;
4812 for path in &route.paths {
4813 if payment_params.payee.blinded_route_hints().len() != 0 {
4814 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4815 if let Some(bt) = &path.blinded_tail {
4816 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4817 if bt.hops.len() > 1 {
4818 assert_eq!(path.hops.last().unwrap().pubkey,
4819 payment_params.payee.blinded_route_hints().iter()
4820 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4821 .map(|(_, p)| p.introduction_node_id).unwrap());
4823 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4826 assert_eq!(path.hops.len(), 2);
4827 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4829 total_amount_paid_msat += path.final_value_msat();
4831 assert_eq!(total_amount_paid_msat, 290_000);
4836 fn long_mpp_route_test() {
4837 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4838 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4839 let scorer = ln_test_utils::TestScorer::new();
4840 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4841 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4842 let config = UserConfig::default();
4843 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4844 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4846 // We need a route consisting of 3 paths:
4847 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4848 // Note that these paths overlap (channels 5, 12, 13).
4849 // We will route 300 sats.
4850 // Each path will have 100 sats capacity, those channels which
4851 // are used twice will have 200 sats capacity.
4853 // Disable other potential paths.
4854 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4855 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4856 short_channel_id: 2,
4859 cltv_expiry_delta: 0,
4860 htlc_minimum_msat: 0,
4861 htlc_maximum_msat: 100_000,
4863 fee_proportional_millionths: 0,
4864 excess_data: Vec::new()
4866 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4867 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4868 short_channel_id: 7,
4871 cltv_expiry_delta: 0,
4872 htlc_minimum_msat: 0,
4873 htlc_maximum_msat: 100_000,
4875 fee_proportional_millionths: 0,
4876 excess_data: Vec::new()
4879 // Path via {node0, node2} is channels {1, 3, 5}.
4880 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4881 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4882 short_channel_id: 1,
4885 cltv_expiry_delta: 0,
4886 htlc_minimum_msat: 0,
4887 htlc_maximum_msat: 100_000,
4889 fee_proportional_millionths: 0,
4890 excess_data: Vec::new()
4892 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4893 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4894 short_channel_id: 3,
4897 cltv_expiry_delta: 0,
4898 htlc_minimum_msat: 0,
4899 htlc_maximum_msat: 100_000,
4901 fee_proportional_millionths: 0,
4902 excess_data: Vec::new()
4905 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4906 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4907 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4908 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4909 short_channel_id: 5,
4912 cltv_expiry_delta: 0,
4913 htlc_minimum_msat: 0,
4914 htlc_maximum_msat: 200_000,
4916 fee_proportional_millionths: 0,
4917 excess_data: Vec::new()
4920 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4921 // Add 100 sats to the capacities of {12, 13}, because these channels
4922 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4923 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4924 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4925 short_channel_id: 12,
4928 cltv_expiry_delta: 0,
4929 htlc_minimum_msat: 0,
4930 htlc_maximum_msat: 200_000,
4932 fee_proportional_millionths: 0,
4933 excess_data: Vec::new()
4935 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4936 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4937 short_channel_id: 13,
4940 cltv_expiry_delta: 0,
4941 htlc_minimum_msat: 0,
4942 htlc_maximum_msat: 200_000,
4944 fee_proportional_millionths: 0,
4945 excess_data: Vec::new()
4948 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4949 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4950 short_channel_id: 6,
4953 cltv_expiry_delta: 0,
4954 htlc_minimum_msat: 0,
4955 htlc_maximum_msat: 100_000,
4957 fee_proportional_millionths: 0,
4958 excess_data: Vec::new()
4960 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4962 short_channel_id: 11,
4965 cltv_expiry_delta: 0,
4966 htlc_minimum_msat: 0,
4967 htlc_maximum_msat: 100_000,
4969 fee_proportional_millionths: 0,
4970 excess_data: Vec::new()
4973 // Path via {node7, node2} is channels {12, 13, 5}.
4974 // We already limited them to 200 sats (they are used twice for 100 sats).
4975 // Nothing to do here.
4978 // Attempt to route more than available results in a failure.
4979 let route_params = RouteParameters::from_payment_params_and_value(
4980 payment_params.clone(), 350_000);
4981 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4982 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4983 &scorer, &Default::default(), &random_seed_bytes) {
4984 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4985 } else { panic!(); }
4989 // Now, attempt to route 300 sats (exact amount we can route).
4990 // Our algorithm should provide us with these 3 paths, 100 sats each.
4991 let route_params = RouteParameters::from_payment_params_and_value(
4992 payment_params, 300_000);
4993 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4994 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4995 assert_eq!(route.paths.len(), 3);
4997 let mut total_amount_paid_msat = 0;
4998 for path in &route.paths {
4999 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5000 total_amount_paid_msat += path.final_value_msat();
5002 assert_eq!(total_amount_paid_msat, 300_000);
5008 fn mpp_cheaper_route_test() {
5009 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5010 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5011 let scorer = ln_test_utils::TestScorer::new();
5012 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5013 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5014 let config = UserConfig::default();
5015 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5017 // This test checks that if we have two cheaper paths and one more expensive path,
5018 // so that liquidity-wise any 2 of 3 combination is sufficient,
5019 // two cheaper paths will be taken.
5020 // These paths have equal available liquidity.
5022 // We need a combination of 3 paths:
5023 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5024 // Note that these paths overlap (channels 5, 12, 13).
5025 // Each path will have 100 sats capacity, those channels which
5026 // are used twice will have 200 sats capacity.
5028 // Disable other potential paths.
5029 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5030 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5031 short_channel_id: 2,
5034 cltv_expiry_delta: 0,
5035 htlc_minimum_msat: 0,
5036 htlc_maximum_msat: 100_000,
5038 fee_proportional_millionths: 0,
5039 excess_data: Vec::new()
5041 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5042 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5043 short_channel_id: 7,
5046 cltv_expiry_delta: 0,
5047 htlc_minimum_msat: 0,
5048 htlc_maximum_msat: 100_000,
5050 fee_proportional_millionths: 0,
5051 excess_data: Vec::new()
5054 // Path via {node0, node2} is channels {1, 3, 5}.
5055 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5056 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5057 short_channel_id: 1,
5060 cltv_expiry_delta: 0,
5061 htlc_minimum_msat: 0,
5062 htlc_maximum_msat: 100_000,
5064 fee_proportional_millionths: 0,
5065 excess_data: Vec::new()
5067 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5068 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5069 short_channel_id: 3,
5072 cltv_expiry_delta: 0,
5073 htlc_minimum_msat: 0,
5074 htlc_maximum_msat: 100_000,
5076 fee_proportional_millionths: 0,
5077 excess_data: Vec::new()
5080 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5081 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5082 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5083 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5084 short_channel_id: 5,
5087 cltv_expiry_delta: 0,
5088 htlc_minimum_msat: 0,
5089 htlc_maximum_msat: 200_000,
5091 fee_proportional_millionths: 0,
5092 excess_data: Vec::new()
5095 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5096 // Add 100 sats to the capacities of {12, 13}, because these channels
5097 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5098 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5099 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5100 short_channel_id: 12,
5103 cltv_expiry_delta: 0,
5104 htlc_minimum_msat: 0,
5105 htlc_maximum_msat: 200_000,
5107 fee_proportional_millionths: 0,
5108 excess_data: Vec::new()
5110 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5111 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5112 short_channel_id: 13,
5115 cltv_expiry_delta: 0,
5116 htlc_minimum_msat: 0,
5117 htlc_maximum_msat: 200_000,
5119 fee_proportional_millionths: 0,
5120 excess_data: Vec::new()
5123 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5124 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5125 short_channel_id: 6,
5128 cltv_expiry_delta: 0,
5129 htlc_minimum_msat: 0,
5130 htlc_maximum_msat: 100_000,
5131 fee_base_msat: 1_000,
5132 fee_proportional_millionths: 0,
5133 excess_data: Vec::new()
5135 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5136 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5137 short_channel_id: 11,
5140 cltv_expiry_delta: 0,
5141 htlc_minimum_msat: 0,
5142 htlc_maximum_msat: 100_000,
5144 fee_proportional_millionths: 0,
5145 excess_data: Vec::new()
5148 // Path via {node7, node2} is channels {12, 13, 5}.
5149 // We already limited them to 200 sats (they are used twice for 100 sats).
5150 // Nothing to do here.
5153 // Now, attempt to route 180 sats.
5154 // Our algorithm should provide us with these 2 paths.
5155 let route_params = RouteParameters::from_payment_params_and_value(
5156 payment_params, 180_000);
5157 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5158 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5159 assert_eq!(route.paths.len(), 2);
5161 let mut total_value_transferred_msat = 0;
5162 let mut total_paid_msat = 0;
5163 for path in &route.paths {
5164 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5165 total_value_transferred_msat += path.final_value_msat();
5166 for hop in &path.hops {
5167 total_paid_msat += hop.fee_msat;
5170 // If we paid fee, this would be higher.
5171 assert_eq!(total_value_transferred_msat, 180_000);
5172 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5173 assert_eq!(total_fees_paid, 0);
5178 fn fees_on_mpp_route_test() {
5179 // This test makes sure that MPP algorithm properly takes into account
5180 // fees charged on the channels, by making the fees impactful:
5181 // if the fee is not properly accounted for, the behavior is different.
5182 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5183 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5184 let scorer = ln_test_utils::TestScorer::new();
5185 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5186 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5187 let config = UserConfig::default();
5188 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5190 // We need a route consisting of 2 paths:
5191 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5192 // We will route 200 sats, Each path will have 100 sats capacity.
5194 // This test is not particularly stable: e.g.,
5195 // there's a way to route via {node0, node2, node4}.
5196 // It works while pathfinding is deterministic, but can be broken otherwise.
5197 // It's fine to ignore this concern for now.
5199 // Disable other potential paths.
5200 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5201 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5202 short_channel_id: 2,
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 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5214 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5215 short_channel_id: 7,
5218 cltv_expiry_delta: 0,
5219 htlc_minimum_msat: 0,
5220 htlc_maximum_msat: 100_000,
5222 fee_proportional_millionths: 0,
5223 excess_data: Vec::new()
5226 // Path via {node0, node2} is channels {1, 3, 5}.
5227 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5228 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5229 short_channel_id: 1,
5232 cltv_expiry_delta: 0,
5233 htlc_minimum_msat: 0,
5234 htlc_maximum_msat: 100_000,
5236 fee_proportional_millionths: 0,
5237 excess_data: Vec::new()
5239 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5240 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5241 short_channel_id: 3,
5244 cltv_expiry_delta: 0,
5245 htlc_minimum_msat: 0,
5246 htlc_maximum_msat: 100_000,
5248 fee_proportional_millionths: 0,
5249 excess_data: Vec::new()
5252 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5253 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5254 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5255 short_channel_id: 5,
5258 cltv_expiry_delta: 0,
5259 htlc_minimum_msat: 0,
5260 htlc_maximum_msat: 100_000,
5262 fee_proportional_millionths: 0,
5263 excess_data: Vec::new()
5266 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5267 // All channels should be 100 sats capacity. But for the fee experiment,
5268 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5269 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5270 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5271 // so no matter how large are other channels,
5272 // the whole path will be limited by 100 sats with just these 2 conditions:
5273 // - channel 12 capacity is 250 sats
5274 // - fee for channel 6 is 150 sats
5275 // Let's test this by enforcing these 2 conditions and removing other limits.
5276 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5277 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5278 short_channel_id: 12,
5281 cltv_expiry_delta: 0,
5282 htlc_minimum_msat: 0,
5283 htlc_maximum_msat: 250_000,
5285 fee_proportional_millionths: 0,
5286 excess_data: Vec::new()
5288 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5289 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5290 short_channel_id: 13,
5293 cltv_expiry_delta: 0,
5294 htlc_minimum_msat: 0,
5295 htlc_maximum_msat: MAX_VALUE_MSAT,
5297 fee_proportional_millionths: 0,
5298 excess_data: Vec::new()
5301 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5303 short_channel_id: 6,
5306 cltv_expiry_delta: 0,
5307 htlc_minimum_msat: 0,
5308 htlc_maximum_msat: MAX_VALUE_MSAT,
5309 fee_base_msat: 150_000,
5310 fee_proportional_millionths: 0,
5311 excess_data: Vec::new()
5313 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5314 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5315 short_channel_id: 11,
5318 cltv_expiry_delta: 0,
5319 htlc_minimum_msat: 0,
5320 htlc_maximum_msat: MAX_VALUE_MSAT,
5322 fee_proportional_millionths: 0,
5323 excess_data: Vec::new()
5327 // Attempt to route more than available results in a failure.
5328 let route_params = RouteParameters::from_payment_params_and_value(
5329 payment_params.clone(), 210_000);
5330 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5331 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5332 &scorer, &Default::default(), &random_seed_bytes) {
5333 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5334 } else { panic!(); }
5338 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5339 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5340 max_total_routing_fee_msat: Some(149_999) };
5341 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5342 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5343 &scorer, &(), &random_seed_bytes) {
5344 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5345 } else { panic!(); }
5349 // Now, attempt to route 200 sats (exact amount we can route).
5350 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5351 max_total_routing_fee_msat: Some(150_000) };
5352 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5353 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5354 assert_eq!(route.paths.len(), 2);
5356 let mut total_amount_paid_msat = 0;
5357 for path in &route.paths {
5358 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5359 total_amount_paid_msat += path.final_value_msat();
5361 assert_eq!(total_amount_paid_msat, 200_000);
5362 assert_eq!(route.get_total_fees(), 150_000);
5367 fn mpp_with_last_hops() {
5368 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5369 // via a single last-hop route hint, we'd fail to route if we first collected routes
5370 // totaling close but not quite enough to fund the full payment.
5372 // This was because we considered last-hop hints to have exactly the sought payment amount
5373 // instead of the amount we were trying to collect, needlessly limiting our path searching
5374 // at the very first hop.
5376 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5377 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5378 // to only have the remaining to-collect amount in available liquidity.
5380 // This bug appeared in production in some specific channel configurations.
5381 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5382 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5383 let scorer = ln_test_utils::TestScorer::new();
5384 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5385 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5386 let config = UserConfig::default();
5387 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5388 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5389 src_node_id: nodes[2],
5390 short_channel_id: 42,
5391 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5392 cltv_expiry_delta: 42,
5393 htlc_minimum_msat: None,
5394 htlc_maximum_msat: None,
5395 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5397 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5398 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5399 // would first use the no-fee route and then fail to find a path along the second route as
5400 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5401 // under 5% of our payment amount.
5402 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5403 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5404 short_channel_id: 1,
5407 cltv_expiry_delta: (5 << 4) | 5,
5408 htlc_minimum_msat: 0,
5409 htlc_maximum_msat: 99_000,
5410 fee_base_msat: u32::max_value(),
5411 fee_proportional_millionths: u32::max_value(),
5412 excess_data: Vec::new()
5414 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5415 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5416 short_channel_id: 2,
5419 cltv_expiry_delta: (5 << 4) | 3,
5420 htlc_minimum_msat: 0,
5421 htlc_maximum_msat: 99_000,
5422 fee_base_msat: u32::max_value(),
5423 fee_proportional_millionths: u32::max_value(),
5424 excess_data: Vec::new()
5426 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5427 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5428 short_channel_id: 4,
5431 cltv_expiry_delta: (4 << 4) | 1,
5432 htlc_minimum_msat: 0,
5433 htlc_maximum_msat: MAX_VALUE_MSAT,
5435 fee_proportional_millionths: 0,
5436 excess_data: Vec::new()
5438 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5439 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5440 short_channel_id: 13,
5442 flags: 0|2, // Channel disabled
5443 cltv_expiry_delta: (13 << 4) | 1,
5444 htlc_minimum_msat: 0,
5445 htlc_maximum_msat: MAX_VALUE_MSAT,
5447 fee_proportional_millionths: 2000000,
5448 excess_data: Vec::new()
5451 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5453 let route_params = RouteParameters::from_payment_params_and_value(
5454 payment_params, 100_000);
5455 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5456 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5457 assert_eq!(route.paths.len(), 2);
5458 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5459 // Paths are manually ordered ordered by SCID, so:
5460 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5461 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5462 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5463 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5464 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5465 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5466 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5467 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5468 assert_eq!(route.get_total_fees(), 1);
5469 assert_eq!(route.get_total_amount(), 100_000);
5473 fn drop_lowest_channel_mpp_route_test() {
5474 // This test checks that low-capacity channel is dropped when after
5475 // path finding we realize that we found more capacity than we need.
5476 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5477 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5478 let scorer = ln_test_utils::TestScorer::new();
5479 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5480 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5481 let config = UserConfig::default();
5482 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5483 .with_max_channel_saturation_power_of_half(0);
5485 // We need a route consisting of 3 paths:
5486 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5488 // The first and the second paths should be sufficient, but the third should be
5489 // cheaper, so that we select it but drop later.
5491 // First, we set limits on these (previously unlimited) channels.
5492 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5494 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5495 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5496 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5497 short_channel_id: 1,
5500 cltv_expiry_delta: 0,
5501 htlc_minimum_msat: 0,
5502 htlc_maximum_msat: 100_000,
5504 fee_proportional_millionths: 0,
5505 excess_data: Vec::new()
5507 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5508 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5509 short_channel_id: 3,
5512 cltv_expiry_delta: 0,
5513 htlc_minimum_msat: 0,
5514 htlc_maximum_msat: 50_000,
5516 fee_proportional_millionths: 0,
5517 excess_data: Vec::new()
5520 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5521 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5522 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5523 short_channel_id: 12,
5526 cltv_expiry_delta: 0,
5527 htlc_minimum_msat: 0,
5528 htlc_maximum_msat: 60_000,
5530 fee_proportional_millionths: 0,
5531 excess_data: Vec::new()
5533 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5534 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5535 short_channel_id: 13,
5538 cltv_expiry_delta: 0,
5539 htlc_minimum_msat: 0,
5540 htlc_maximum_msat: 60_000,
5542 fee_proportional_millionths: 0,
5543 excess_data: Vec::new()
5546 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5547 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5548 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5549 short_channel_id: 2,
5552 cltv_expiry_delta: 0,
5553 htlc_minimum_msat: 0,
5554 htlc_maximum_msat: 20_000,
5556 fee_proportional_millionths: 0,
5557 excess_data: Vec::new()
5559 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5560 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5561 short_channel_id: 4,
5564 cltv_expiry_delta: 0,
5565 htlc_minimum_msat: 0,
5566 htlc_maximum_msat: 20_000,
5568 fee_proportional_millionths: 0,
5569 excess_data: Vec::new()
5573 // Attempt to route more than available results in a failure.
5574 let route_params = RouteParameters::from_payment_params_and_value(
5575 payment_params.clone(), 150_000);
5576 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5577 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5578 &scorer, &Default::default(), &random_seed_bytes) {
5579 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5580 } else { panic!(); }
5584 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5585 // Our algorithm should provide us with these 3 paths.
5586 let route_params = RouteParameters::from_payment_params_and_value(
5587 payment_params.clone(), 125_000);
5588 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5589 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5590 assert_eq!(route.paths.len(), 3);
5591 let mut total_amount_paid_msat = 0;
5592 for path in &route.paths {
5593 assert_eq!(path.hops.len(), 2);
5594 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5595 total_amount_paid_msat += path.final_value_msat();
5597 assert_eq!(total_amount_paid_msat, 125_000);
5601 // Attempt to route without the last small cheap channel
5602 let route_params = RouteParameters::from_payment_params_and_value(
5603 payment_params, 90_000);
5604 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5605 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5606 assert_eq!(route.paths.len(), 2);
5607 let mut total_amount_paid_msat = 0;
5608 for path in &route.paths {
5609 assert_eq!(path.hops.len(), 2);
5610 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5611 total_amount_paid_msat += path.final_value_msat();
5613 assert_eq!(total_amount_paid_msat, 90_000);
5618 fn min_criteria_consistency() {
5619 // Test that we don't use an inconsistent metric between updating and walking nodes during
5620 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5621 // was updated with a different criterion from the heap sorting, resulting in loops in
5622 // calculated paths. We test for that specific case here.
5624 // We construct a network that looks like this:
5626 // node2 -1(3)2- node3
5630 // node1 -1(5)2- node4 -1(1)2- node6
5636 // We create a loop on the side of our real path - our destination is node 6, with a
5637 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5638 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5639 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5640 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5641 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5642 // "previous hop" being set to node 3, creating a loop in the path.
5643 let secp_ctx = Secp256k1::new();
5644 let logger = Arc::new(ln_test_utils::TestLogger::new());
5645 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5646 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5647 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5648 let scorer = ln_test_utils::TestScorer::new();
5649 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5650 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5651 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5653 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5654 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5655 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5656 short_channel_id: 6,
5659 cltv_expiry_delta: (6 << 4) | 0,
5660 htlc_minimum_msat: 0,
5661 htlc_maximum_msat: MAX_VALUE_MSAT,
5663 fee_proportional_millionths: 0,
5664 excess_data: Vec::new()
5666 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5668 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5669 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5670 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5671 short_channel_id: 5,
5674 cltv_expiry_delta: (5 << 4) | 0,
5675 htlc_minimum_msat: 0,
5676 htlc_maximum_msat: MAX_VALUE_MSAT,
5678 fee_proportional_millionths: 0,
5679 excess_data: Vec::new()
5681 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5683 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5684 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5685 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5686 short_channel_id: 4,
5689 cltv_expiry_delta: (4 << 4) | 0,
5690 htlc_minimum_msat: 0,
5691 htlc_maximum_msat: MAX_VALUE_MSAT,
5693 fee_proportional_millionths: 0,
5694 excess_data: Vec::new()
5696 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5698 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5699 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5700 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5701 short_channel_id: 3,
5704 cltv_expiry_delta: (3 << 4) | 0,
5705 htlc_minimum_msat: 0,
5706 htlc_maximum_msat: MAX_VALUE_MSAT,
5708 fee_proportional_millionths: 0,
5709 excess_data: Vec::new()
5711 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5713 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5714 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5715 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5716 short_channel_id: 2,
5719 cltv_expiry_delta: (2 << 4) | 0,
5720 htlc_minimum_msat: 0,
5721 htlc_maximum_msat: MAX_VALUE_MSAT,
5723 fee_proportional_millionths: 0,
5724 excess_data: Vec::new()
5727 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5728 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5729 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5730 short_channel_id: 1,
5733 cltv_expiry_delta: (1 << 4) | 0,
5734 htlc_minimum_msat: 100,
5735 htlc_maximum_msat: MAX_VALUE_MSAT,
5737 fee_proportional_millionths: 0,
5738 excess_data: Vec::new()
5740 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5743 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5744 let route_params = RouteParameters::from_payment_params_and_value(
5745 payment_params, 10_000);
5746 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5747 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5748 assert_eq!(route.paths.len(), 1);
5749 assert_eq!(route.paths[0].hops.len(), 3);
5751 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5752 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5753 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5754 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5755 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5756 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5758 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5759 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5760 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5761 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5762 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5763 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5765 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5766 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5767 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5768 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5769 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5770 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5776 fn exact_fee_liquidity_limit() {
5777 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5778 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5779 // we calculated fees on a higher value, resulting in us ignoring such paths.
5780 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5781 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5782 let scorer = ln_test_utils::TestScorer::new();
5783 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5784 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5785 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5787 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5789 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5790 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5791 short_channel_id: 2,
5794 cltv_expiry_delta: 0,
5795 htlc_minimum_msat: 0,
5796 htlc_maximum_msat: 85_000,
5798 fee_proportional_millionths: 0,
5799 excess_data: Vec::new()
5802 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5803 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5804 short_channel_id: 12,
5807 cltv_expiry_delta: (4 << 4) | 1,
5808 htlc_minimum_msat: 0,
5809 htlc_maximum_msat: 270_000,
5811 fee_proportional_millionths: 1000000,
5812 excess_data: Vec::new()
5816 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5817 // 200% fee charged channel 13 in the 1-to-2 direction.
5818 let mut route_params = RouteParameters::from_payment_params_and_value(
5819 payment_params, 90_000);
5820 route_params.max_total_routing_fee_msat = Some(90_000*2);
5821 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5822 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5823 assert_eq!(route.paths.len(), 1);
5824 assert_eq!(route.paths[0].hops.len(), 2);
5826 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5827 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5828 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5829 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5830 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5831 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5833 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5834 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5835 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5836 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5837 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5838 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5843 fn htlc_max_reduction_below_min() {
5844 // Test that if, while walking the graph, we reduce the value being sent to meet an
5845 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5846 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5847 // resulting in us thinking there is no possible path, even if other paths exist.
5848 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5849 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5850 let scorer = ln_test_utils::TestScorer::new();
5851 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5852 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5853 let config = UserConfig::default();
5854 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5856 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5857 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5858 // then try to send 90_000.
5859 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5860 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5861 short_channel_id: 2,
5864 cltv_expiry_delta: 0,
5865 htlc_minimum_msat: 0,
5866 htlc_maximum_msat: 80_000,
5868 fee_proportional_millionths: 0,
5869 excess_data: Vec::new()
5871 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5872 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5873 short_channel_id: 4,
5876 cltv_expiry_delta: (4 << 4) | 1,
5877 htlc_minimum_msat: 90_000,
5878 htlc_maximum_msat: MAX_VALUE_MSAT,
5880 fee_proportional_millionths: 0,
5881 excess_data: Vec::new()
5885 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5886 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5887 // expensive) channels 12-13 path.
5888 let mut route_params = RouteParameters::from_payment_params_and_value(
5889 payment_params, 90_000);
5890 route_params.max_total_routing_fee_msat = Some(90_000*2);
5891 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5892 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5893 assert_eq!(route.paths.len(), 1);
5894 assert_eq!(route.paths[0].hops.len(), 2);
5896 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5897 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5898 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5899 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5900 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5901 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5903 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5904 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5905 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5906 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5907 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5908 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5913 fn multiple_direct_first_hops() {
5914 // Previously we'd only ever considered one first hop path per counterparty.
5915 // However, as we don't restrict users to one channel per peer, we really need to support
5916 // looking at all first hop paths.
5917 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5918 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5919 // route over multiple channels with the same first hop.
5920 let secp_ctx = Secp256k1::new();
5921 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5922 let logger = Arc::new(ln_test_utils::TestLogger::new());
5923 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5924 let scorer = ln_test_utils::TestScorer::new();
5925 let config = UserConfig::default();
5926 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5927 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5928 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5931 let route_params = RouteParameters::from_payment_params_and_value(
5932 payment_params.clone(), 100_000);
5933 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5934 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5935 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5936 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5937 assert_eq!(route.paths.len(), 1);
5938 assert_eq!(route.paths[0].hops.len(), 1);
5940 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5941 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5942 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5945 let route_params = RouteParameters::from_payment_params_and_value(
5946 payment_params.clone(), 100_000);
5947 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5948 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5949 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5950 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5951 assert_eq!(route.paths.len(), 2);
5952 assert_eq!(route.paths[0].hops.len(), 1);
5953 assert_eq!(route.paths[1].hops.len(), 1);
5955 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5956 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5958 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5959 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5961 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5962 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5966 // If we have a bunch of outbound channels to the same node, where most are not
5967 // sufficient to pay the full payment, but one is, we should default to just using the
5968 // one single channel that has sufficient balance, avoiding MPP.
5970 // If we have several options above the 3xpayment value threshold, we should pick the
5971 // smallest of them, avoiding further fragmenting our available outbound balance to
5973 let route_params = RouteParameters::from_payment_params_and_value(
5974 payment_params, 100_000);
5975 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5976 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5977 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5978 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5979 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5980 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5981 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5982 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5983 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5984 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5985 assert_eq!(route.paths.len(), 1);
5986 assert_eq!(route.paths[0].hops.len(), 1);
5988 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5989 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5990 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5995 fn prefers_shorter_route_with_higher_fees() {
5996 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5997 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5998 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6000 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6001 let scorer = ln_test_utils::TestScorer::new();
6002 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6003 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6004 let route_params = RouteParameters::from_payment_params_and_value(
6005 payment_params.clone(), 100);
6006 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6007 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6008 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6010 assert_eq!(route.get_total_fees(), 100);
6011 assert_eq!(route.get_total_amount(), 100);
6012 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6014 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6015 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6016 let scorer = FixedPenaltyScorer::with_penalty(100);
6017 let route_params = RouteParameters::from_payment_params_and_value(
6018 payment_params, 100);
6019 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6020 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6021 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6023 assert_eq!(route.get_total_fees(), 300);
6024 assert_eq!(route.get_total_amount(), 100);
6025 assert_eq!(path, vec![2, 4, 7, 10]);
6028 struct BadChannelScorer {
6029 short_channel_id: u64,
6033 impl Writeable for BadChannelScorer {
6034 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6036 impl ScoreLookUp for BadChannelScorer {
6037 type ScoreParams = ();
6038 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6039 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
6043 struct BadNodeScorer {
6048 impl Writeable for BadNodeScorer {
6049 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6052 impl ScoreLookUp for BadNodeScorer {
6053 type ScoreParams = ();
6054 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6055 if *target == self.node_id { u64::max_value() } else { 0 }
6060 fn avoids_routing_through_bad_channels_and_nodes() {
6061 let (secp_ctx, network, _, _, 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();
6064 let network_graph = network.read_only();
6066 // A path to nodes[6] exists when no penalties are applied to any channel.
6067 let scorer = ln_test_utils::TestScorer::new();
6068 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6069 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6070 let route_params = RouteParameters::from_payment_params_and_value(
6071 payment_params, 100);
6072 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6073 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6074 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6076 assert_eq!(route.get_total_fees(), 100);
6077 assert_eq!(route.get_total_amount(), 100);
6078 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6080 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6081 let scorer = BadChannelScorer { short_channel_id: 6 };
6082 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6083 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6084 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6086 assert_eq!(route.get_total_fees(), 300);
6087 assert_eq!(route.get_total_amount(), 100);
6088 assert_eq!(path, vec![2, 4, 7, 10]);
6090 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6091 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6092 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6093 &scorer, &Default::default(), &random_seed_bytes) {
6094 Err(LightningError { err, .. } ) => {
6095 assert_eq!(err, "Failed to find a path to the given destination");
6097 Ok(_) => panic!("Expected error"),
6102 fn total_fees_single_path() {
6104 paths: vec![Path { hops: vec![
6106 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6107 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6108 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6111 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6112 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6113 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6116 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6117 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6118 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6120 ], blinded_tail: None }],
6124 assert_eq!(route.get_total_fees(), 250);
6125 assert_eq!(route.get_total_amount(), 225);
6129 fn total_fees_multi_path() {
6131 paths: vec![Path { hops: vec![
6133 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6134 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6135 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6138 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6139 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6140 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6142 ], blinded_tail: None }, Path { hops: vec![
6144 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6145 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6146 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6149 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6150 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6151 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6153 ], blinded_tail: None }],
6157 assert_eq!(route.get_total_fees(), 200);
6158 assert_eq!(route.get_total_amount(), 300);
6162 fn total_empty_route_no_panic() {
6163 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6164 // would both panic if the route was completely empty. We test to ensure they return 0
6165 // here, even though its somewhat nonsensical as a route.
6166 let route = Route { paths: Vec::new(), route_params: None };
6168 assert_eq!(route.get_total_fees(), 0);
6169 assert_eq!(route.get_total_amount(), 0);
6173 fn limits_total_cltv_delta() {
6174 let (secp_ctx, network, _, _, logger) = build_graph();
6175 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6176 let network_graph = network.read_only();
6178 let scorer = ln_test_utils::TestScorer::new();
6180 // Make sure that generally there is at least one route available
6181 let feasible_max_total_cltv_delta = 1008;
6182 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6183 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6184 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6185 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6186 let route_params = RouteParameters::from_payment_params_and_value(
6187 feasible_payment_params, 100);
6188 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6189 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6190 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6191 assert_ne!(path.len(), 0);
6193 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6194 let fail_max_total_cltv_delta = 23;
6195 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6196 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6197 let route_params = RouteParameters::from_payment_params_and_value(
6198 fail_payment_params, 100);
6199 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6200 &Default::default(), &random_seed_bytes)
6202 Err(LightningError { err, .. } ) => {
6203 assert_eq!(err, "Failed to find a path to the given destination");
6205 Ok(_) => panic!("Expected error"),
6210 fn avoids_recently_failed_paths() {
6211 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6212 // randomly inserting channels into it until we can't find a route anymore.
6213 let (secp_ctx, network, _, _, logger) = build_graph();
6214 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6215 let network_graph = network.read_only();
6217 let scorer = ln_test_utils::TestScorer::new();
6218 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6219 .with_max_path_count(1);
6220 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6221 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6223 // We should be able to find a route initially, and then after we fail a few random
6224 // channels eventually we won't be able to any longer.
6225 let route_params = RouteParameters::from_payment_params_and_value(
6226 payment_params.clone(), 100);
6227 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6228 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6230 let route_params = RouteParameters::from_payment_params_and_value(
6231 payment_params.clone(), 100);
6232 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6233 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6235 for chan in route.paths[0].hops.iter() {
6236 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6238 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6239 % route.paths[0].hops.len();
6240 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6246 fn limits_path_length() {
6247 let (secp_ctx, network, _, _, logger) = build_line_graph();
6248 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6249 let network_graph = network.read_only();
6251 let scorer = ln_test_utils::TestScorer::new();
6252 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6253 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6255 // First check we can actually create a long route on this graph.
6256 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6257 let route_params = RouteParameters::from_payment_params_and_value(
6258 feasible_payment_params, 100);
6259 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6260 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6261 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6262 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6264 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6265 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6266 let route_params = RouteParameters::from_payment_params_and_value(
6267 fail_payment_params, 100);
6268 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6269 &Default::default(), &random_seed_bytes)
6271 Err(LightningError { err, .. } ) => {
6272 assert_eq!(err, "Failed to find a path to the given destination");
6274 Ok(_) => panic!("Expected error"),
6279 fn adds_and_limits_cltv_offset() {
6280 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6281 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6283 let scorer = ln_test_utils::TestScorer::new();
6285 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6286 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6287 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6288 let route_params = RouteParameters::from_payment_params_and_value(
6289 payment_params.clone(), 100);
6290 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6291 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6292 assert_eq!(route.paths.len(), 1);
6294 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6296 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6297 let mut route_default = route.clone();
6298 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6299 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6300 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6301 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6302 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6304 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6305 let mut route_limited = route.clone();
6306 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6307 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6308 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6309 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6310 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6314 fn adds_plausible_cltv_offset() {
6315 let (secp_ctx, network, _, _, logger) = build_graph();
6316 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6317 let network_graph = network.read_only();
6318 let network_nodes = network_graph.nodes();
6319 let network_channels = network_graph.channels();
6320 let scorer = ln_test_utils::TestScorer::new();
6321 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6322 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6323 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6325 let route_params = RouteParameters::from_payment_params_and_value(
6326 payment_params.clone(), 100);
6327 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6328 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6329 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6331 let mut path_plausibility = vec![];
6333 for p in route.paths {
6334 // 1. Select random observation point
6335 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6336 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6338 prng.process_in_place(&mut random_bytes);
6339 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6340 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6342 // 2. Calculate what CLTV expiry delta we would observe there
6343 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6345 // 3. Starting from the observation point, find candidate paths
6346 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6347 candidates.push_back((observation_point, vec![]));
6349 let mut found_plausible_candidate = false;
6351 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6352 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6353 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6354 found_plausible_candidate = true;
6355 break 'candidate_loop;
6359 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6360 for channel_id in &cur_node.channels {
6361 if let Some(channel_info) = network_channels.get(&channel_id) {
6362 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6363 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6364 if cur_path_cltv_deltas.iter().sum::<u32>()
6365 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6366 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6367 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6368 candidates.push_back((*next_id, new_path_cltv_deltas));
6376 path_plausibility.push(found_plausible_candidate);
6378 assert!(path_plausibility.iter().all(|x| *x));
6382 fn builds_correct_path_from_hops() {
6383 let (secp_ctx, network, _, _, logger) = build_graph();
6384 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6385 let network_graph = network.read_only();
6387 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6388 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6390 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6391 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6392 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6393 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6394 Arc::clone(&logger), &random_seed_bytes).unwrap();
6395 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6396 assert_eq!(hops.len(), route.paths[0].hops.len());
6397 for (idx, hop_pubkey) in hops.iter().enumerate() {
6398 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6403 fn avoids_saturating_channels() {
6404 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6405 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6406 let decay_params = ProbabilisticScoringDecayParameters::default();
6407 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6409 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6410 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6411 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6412 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6413 short_channel_id: 4,
6416 cltv_expiry_delta: (4 << 4) | 1,
6417 htlc_minimum_msat: 0,
6418 htlc_maximum_msat: 250_000_000,
6420 fee_proportional_millionths: 0,
6421 excess_data: Vec::new()
6423 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6424 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6425 short_channel_id: 13,
6428 cltv_expiry_delta: (13 << 4) | 1,
6429 htlc_minimum_msat: 0,
6430 htlc_maximum_msat: 250_000_000,
6432 fee_proportional_millionths: 0,
6433 excess_data: Vec::new()
6436 let config = UserConfig::default();
6437 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6438 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6439 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6440 // 100,000 sats is less than the available liquidity on each channel, set above.
6441 let route_params = RouteParameters::from_payment_params_and_value(
6442 payment_params, 100_000_000);
6443 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6444 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6445 assert_eq!(route.paths.len(), 2);
6446 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6447 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6450 #[cfg(not(feature = "no-std"))]
6451 pub(super) fn random_init_seed() -> u64 {
6452 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6453 use core::hash::{BuildHasher, Hasher};
6454 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6455 println!("Using seed of {}", seed);
6460 #[cfg(not(feature = "no-std"))]
6461 fn generate_routes() {
6462 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6464 let logger = ln_test_utils::TestLogger::new();
6465 let graph = match super::bench_utils::read_network_graph(&logger) {
6473 let params = ProbabilisticScoringFeeParameters::default();
6474 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6475 let features = super::Bolt11InvoiceFeatures::empty();
6477 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6481 #[cfg(not(feature = "no-std"))]
6482 fn generate_routes_mpp() {
6483 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6485 let logger = ln_test_utils::TestLogger::new();
6486 let graph = match super::bench_utils::read_network_graph(&logger) {
6494 let params = ProbabilisticScoringFeeParameters::default();
6495 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6496 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6498 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6502 #[cfg(not(feature = "no-std"))]
6503 fn generate_large_mpp_routes() {
6504 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6506 let logger = ln_test_utils::TestLogger::new();
6507 let graph = match super::bench_utils::read_network_graph(&logger) {
6515 let params = ProbabilisticScoringFeeParameters::default();
6516 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6517 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6519 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6523 fn honors_manual_penalties() {
6524 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6525 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6527 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6528 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6530 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6531 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6533 // First check set manual penalties are returned by the scorer.
6534 let usage = ChannelUsage {
6536 inflight_htlc_msat: 0,
6537 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6539 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6540 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6541 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6543 // Then check we can get a normal route
6544 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6545 let route_params = RouteParameters::from_payment_params_and_value(
6546 payment_params, 100);
6547 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6548 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6549 assert!(route.is_ok());
6551 // Then check that we can't get a route if we ban an intermediate node.
6552 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6553 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6554 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6555 assert!(route.is_err());
6557 // Finally make sure we can route again, when we remove the ban.
6558 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6559 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6560 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6561 assert!(route.is_ok());
6565 fn abide_by_route_hint_max_htlc() {
6566 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6567 // params in the final route.
6568 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6569 let netgraph = network_graph.read_only();
6570 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6571 let scorer = ln_test_utils::TestScorer::new();
6572 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6573 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6574 let config = UserConfig::default();
6576 let max_htlc_msat = 50_000;
6577 let route_hint_1 = RouteHint(vec![RouteHintHop {
6578 src_node_id: nodes[2],
6579 short_channel_id: 42,
6582 proportional_millionths: 0,
6584 cltv_expiry_delta: 10,
6585 htlc_minimum_msat: None,
6586 htlc_maximum_msat: Some(max_htlc_msat),
6588 let dest_node_id = ln_test_utils::pubkey(42);
6589 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6590 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6591 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6593 // Make sure we'll error if our route hints don't have enough liquidity according to their
6594 // htlc_maximum_msat.
6595 let mut route_params = RouteParameters::from_payment_params_and_value(
6596 payment_params, max_htlc_msat + 1);
6597 route_params.max_total_routing_fee_msat = None;
6598 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6599 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6602 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6603 } else { panic!(); }
6605 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6606 let mut route_hint_2 = route_hint_1.clone();
6607 route_hint_2.0[0].short_channel_id = 43;
6608 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6609 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6610 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6611 let mut route_params = RouteParameters::from_payment_params_and_value(
6612 payment_params, max_htlc_msat + 1);
6613 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6614 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6615 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6616 assert_eq!(route.paths.len(), 2);
6617 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6618 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6622 fn direct_channel_to_hints_with_max_htlc() {
6623 // Check that if we have a first hop channel peer that's connected to multiple provided route
6624 // hints, that we properly split the payment between the route hints if needed.
6625 let logger = Arc::new(ln_test_utils::TestLogger::new());
6626 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6627 let scorer = ln_test_utils::TestScorer::new();
6628 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6629 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6630 let config = UserConfig::default();
6632 let our_node_id = ln_test_utils::pubkey(42);
6633 let intermed_node_id = ln_test_utils::pubkey(43);
6634 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6636 let amt_msat = 900_000;
6637 let max_htlc_msat = 500_000;
6638 let route_hint_1 = RouteHint(vec![RouteHintHop {
6639 src_node_id: intermed_node_id,
6640 short_channel_id: 44,
6643 proportional_millionths: 0,
6645 cltv_expiry_delta: 10,
6646 htlc_minimum_msat: None,
6647 htlc_maximum_msat: Some(max_htlc_msat),
6649 src_node_id: intermed_node_id,
6650 short_channel_id: 45,
6653 proportional_millionths: 0,
6655 cltv_expiry_delta: 10,
6656 htlc_minimum_msat: None,
6657 // Check that later route hint max htlcs don't override earlier ones
6658 htlc_maximum_msat: Some(max_htlc_msat - 50),
6660 let mut route_hint_2 = route_hint_1.clone();
6661 route_hint_2.0[0].short_channel_id = 46;
6662 route_hint_2.0[1].short_channel_id = 47;
6663 let dest_node_id = ln_test_utils::pubkey(44);
6664 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6665 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6666 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6668 let route_params = RouteParameters::from_payment_params_and_value(
6669 payment_params, amt_msat);
6670 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6671 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6672 &Default::default(), &random_seed_bytes).unwrap();
6673 assert_eq!(route.paths.len(), 2);
6674 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6675 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6676 assert_eq!(route.get_total_amount(), amt_msat);
6678 // Re-run but with two first hop channels connected to the same route hint peers that must be
6680 let first_hops = vec![
6681 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6682 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6684 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6685 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6686 &Default::default(), &random_seed_bytes).unwrap();
6687 assert_eq!(route.paths.len(), 2);
6688 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6689 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6690 assert_eq!(route.get_total_amount(), amt_msat);
6692 // Make sure this works for blinded route hints.
6693 let blinded_path = BlindedPath {
6694 introduction_node_id: intermed_node_id,
6695 blinding_point: ln_test_utils::pubkey(42),
6697 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6698 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6701 let blinded_payinfo = BlindedPayInfo {
6703 fee_proportional_millionths: 0,
6704 htlc_minimum_msat: 1,
6705 htlc_maximum_msat: max_htlc_msat,
6706 cltv_expiry_delta: 10,
6707 features: BlindedHopFeatures::empty(),
6709 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6710 let payment_params = PaymentParameters::blinded(vec![
6711 (blinded_payinfo.clone(), blinded_path.clone()),
6712 (blinded_payinfo.clone(), blinded_path.clone())])
6713 .with_bolt12_features(bolt12_features).unwrap();
6714 let route_params = RouteParameters::from_payment_params_and_value(
6715 payment_params, amt_msat);
6716 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6717 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6718 &Default::default(), &random_seed_bytes).unwrap();
6719 assert_eq!(route.paths.len(), 2);
6720 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6721 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6722 assert_eq!(route.get_total_amount(), amt_msat);
6726 fn blinded_route_ser() {
6727 let blinded_path_1 = BlindedPath {
6728 introduction_node_id: ln_test_utils::pubkey(42),
6729 blinding_point: ln_test_utils::pubkey(43),
6731 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6732 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6735 let blinded_path_2 = BlindedPath {
6736 introduction_node_id: ln_test_utils::pubkey(46),
6737 blinding_point: ln_test_utils::pubkey(47),
6739 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6740 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6743 // (De)serialize a Route with 1 blinded path out of two total paths.
6744 let mut route = Route { paths: vec![Path {
6745 hops: vec![RouteHop {
6746 pubkey: ln_test_utils::pubkey(50),
6747 node_features: NodeFeatures::empty(),
6748 short_channel_id: 42,
6749 channel_features: ChannelFeatures::empty(),
6751 cltv_expiry_delta: 0,
6752 maybe_announced_channel: true,
6754 blinded_tail: Some(BlindedTail {
6755 hops: blinded_path_1.blinded_hops,
6756 blinding_point: blinded_path_1.blinding_point,
6757 excess_final_cltv_expiry_delta: 40,
6758 final_value_msat: 100,
6760 hops: vec![RouteHop {
6761 pubkey: ln_test_utils::pubkey(51),
6762 node_features: NodeFeatures::empty(),
6763 short_channel_id: 43,
6764 channel_features: ChannelFeatures::empty(),
6766 cltv_expiry_delta: 0,
6767 maybe_announced_channel: true,
6768 }], blinded_tail: None }],
6771 let encoded_route = route.encode();
6772 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6773 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6774 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6776 // (De)serialize a Route with two paths, each containing a blinded tail.
6777 route.paths[1].blinded_tail = Some(BlindedTail {
6778 hops: blinded_path_2.blinded_hops,
6779 blinding_point: blinded_path_2.blinding_point,
6780 excess_final_cltv_expiry_delta: 41,
6781 final_value_msat: 101,
6783 let encoded_route = route.encode();
6784 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6785 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6786 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6790 fn blinded_path_inflight_processing() {
6791 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6792 // account for the blinded tail's final amount_msat.
6793 let mut inflight_htlcs = InFlightHtlcs::new();
6794 let blinded_path = BlindedPath {
6795 introduction_node_id: ln_test_utils::pubkey(43),
6796 blinding_point: ln_test_utils::pubkey(48),
6797 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6800 hops: vec![RouteHop {
6801 pubkey: ln_test_utils::pubkey(42),
6802 node_features: NodeFeatures::empty(),
6803 short_channel_id: 42,
6804 channel_features: ChannelFeatures::empty(),
6806 cltv_expiry_delta: 0,
6807 maybe_announced_channel: false,
6810 pubkey: blinded_path.introduction_node_id,
6811 node_features: NodeFeatures::empty(),
6812 short_channel_id: 43,
6813 channel_features: ChannelFeatures::empty(),
6815 cltv_expiry_delta: 0,
6816 maybe_announced_channel: false,
6818 blinded_tail: Some(BlindedTail {
6819 hops: blinded_path.blinded_hops,
6820 blinding_point: blinded_path.blinding_point,
6821 excess_final_cltv_expiry_delta: 0,
6822 final_value_msat: 200,
6825 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6826 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6827 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6831 fn blinded_path_cltv_shadow_offset() {
6832 // Make sure we add a shadow offset when sending to blinded paths.
6833 let blinded_path = BlindedPath {
6834 introduction_node_id: ln_test_utils::pubkey(43),
6835 blinding_point: ln_test_utils::pubkey(44),
6837 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6838 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6841 let mut route = Route { paths: vec![Path {
6842 hops: vec![RouteHop {
6843 pubkey: ln_test_utils::pubkey(42),
6844 node_features: NodeFeatures::empty(),
6845 short_channel_id: 42,
6846 channel_features: ChannelFeatures::empty(),
6848 cltv_expiry_delta: 0,
6849 maybe_announced_channel: false,
6852 pubkey: blinded_path.introduction_node_id,
6853 node_features: NodeFeatures::empty(),
6854 short_channel_id: 43,
6855 channel_features: ChannelFeatures::empty(),
6857 cltv_expiry_delta: 0,
6858 maybe_announced_channel: false,
6861 blinded_tail: Some(BlindedTail {
6862 hops: blinded_path.blinded_hops,
6863 blinding_point: blinded_path.blinding_point,
6864 excess_final_cltv_expiry_delta: 0,
6865 final_value_msat: 200,
6867 }], route_params: None};
6869 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6870 let (_, network_graph, _, _, _) = build_line_graph();
6871 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6872 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6873 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6877 fn simple_blinded_route_hints() {
6878 do_simple_blinded_route_hints(1);
6879 do_simple_blinded_route_hints(2);
6880 do_simple_blinded_route_hints(3);
6883 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6884 // Check that we can generate a route to a blinded path with the expected hops.
6885 let (secp_ctx, network, _, _, logger) = build_graph();
6886 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6887 let network_graph = network.read_only();
6889 let scorer = ln_test_utils::TestScorer::new();
6890 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6891 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6893 let mut blinded_path = BlindedPath {
6894 introduction_node_id: nodes[2],
6895 blinding_point: ln_test_utils::pubkey(42),
6896 blinded_hops: Vec::with_capacity(num_blinded_hops),
6898 for i in 0..num_blinded_hops {
6899 blinded_path.blinded_hops.push(
6900 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6903 let blinded_payinfo = BlindedPayInfo {
6905 fee_proportional_millionths: 500,
6906 htlc_minimum_msat: 1000,
6907 htlc_maximum_msat: 100_000_000,
6908 cltv_expiry_delta: 15,
6909 features: BlindedHopFeatures::empty(),
6912 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6913 let route_params = RouteParameters::from_payment_params_and_value(
6914 payment_params, 1001);
6915 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6916 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6917 assert_eq!(route.paths.len(), 1);
6918 assert_eq!(route.paths[0].hops.len(), 2);
6920 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6921 assert_eq!(tail.hops, blinded_path.blinded_hops);
6922 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6923 assert_eq!(tail.final_value_msat, 1001);
6925 let final_hop = route.paths[0].hops.last().unwrap();
6926 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6927 if tail.hops.len() > 1 {
6928 assert_eq!(final_hop.fee_msat,
6929 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6930 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6932 assert_eq!(final_hop.fee_msat, 0);
6933 assert_eq!(final_hop.cltv_expiry_delta, 0);
6938 fn blinded_path_routing_errors() {
6939 // Check that we can generate a route to a blinded path with the expected hops.
6940 let (secp_ctx, network, _, _, logger) = build_graph();
6941 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6942 let network_graph = network.read_only();
6944 let scorer = ln_test_utils::TestScorer::new();
6945 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6946 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6948 let mut invalid_blinded_path = BlindedPath {
6949 introduction_node_id: nodes[2],
6950 blinding_point: ln_test_utils::pubkey(42),
6952 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
6955 let blinded_payinfo = BlindedPayInfo {
6957 fee_proportional_millionths: 500,
6958 htlc_minimum_msat: 1000,
6959 htlc_maximum_msat: 100_000_000,
6960 cltv_expiry_delta: 15,
6961 features: BlindedHopFeatures::empty(),
6964 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
6965 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
6966 let payment_params = PaymentParameters::blinded(vec![
6967 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
6968 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
6969 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6970 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6971 &scorer, &Default::default(), &random_seed_bytes)
6973 Err(LightningError { err, .. }) => {
6974 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
6976 _ => panic!("Expected error")
6979 invalid_blinded_path.introduction_node_id = our_id;
6980 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
6981 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6982 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6983 &Default::default(), &random_seed_bytes)
6985 Err(LightningError { err, .. }) => {
6986 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
6988 _ => panic!("Expected error")
6991 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
6992 invalid_blinded_path.blinded_hops.clear();
6993 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
6994 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6995 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6996 &Default::default(), &random_seed_bytes)
6998 Err(LightningError { err, .. }) => {
6999 assert_eq!(err, "0-hop blinded path provided");
7001 _ => panic!("Expected error")
7006 fn matching_intro_node_paths_provided() {
7007 // Check that if multiple blinded paths with the same intro node are provided in payment
7008 // parameters, we'll return the correct paths in the resulting MPP route.
7009 let (secp_ctx, network, _, _, logger) = build_graph();
7010 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7011 let network_graph = network.read_only();
7013 let scorer = ln_test_utils::TestScorer::new();
7014 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7015 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7016 let config = UserConfig::default();
7018 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7019 let blinded_path_1 = BlindedPath {
7020 introduction_node_id: nodes[2],
7021 blinding_point: ln_test_utils::pubkey(42),
7023 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7024 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7027 let blinded_payinfo_1 = BlindedPayInfo {
7029 fee_proportional_millionths: 0,
7030 htlc_minimum_msat: 0,
7031 htlc_maximum_msat: 30_000,
7032 cltv_expiry_delta: 0,
7033 features: BlindedHopFeatures::empty(),
7036 let mut blinded_path_2 = blinded_path_1.clone();
7037 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7038 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7039 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7041 let blinded_hints = vec![
7042 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7043 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7045 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7046 .with_bolt12_features(bolt12_features.clone()).unwrap();
7048 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7049 route_params.max_total_routing_fee_msat = Some(100_000);
7050 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7051 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7052 assert_eq!(route.paths.len(), 2);
7053 let mut total_amount_paid_msat = 0;
7054 for path in route.paths.into_iter() {
7055 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7056 if let Some(bt) = &path.blinded_tail {
7057 assert_eq!(bt.blinding_point,
7058 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7059 .map(|(_, bp)| bp.blinding_point).unwrap());
7060 } else { panic!(); }
7061 total_amount_paid_msat += path.final_value_msat();
7063 assert_eq!(total_amount_paid_msat, 100_000);
7067 fn direct_to_intro_node() {
7068 // This previously caused a debug panic in the router when asserting
7069 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7070 // direct channels we failed to account for the fee charged for use of the blinded path.
7073 // node0 -1(1)2 - node1
7074 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7075 // doesn't account for the blinded path fee.
7077 let secp_ctx = Secp256k1::new();
7078 let logger = Arc::new(ln_test_utils::TestLogger::new());
7079 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7080 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7081 let scorer = ln_test_utils::TestScorer::new();
7082 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7083 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7085 let amt_msat = 10_000_000;
7086 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7087 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7088 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7089 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7090 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7091 short_channel_id: 1,
7094 cltv_expiry_delta: 42,
7095 htlc_minimum_msat: 1_000,
7096 htlc_maximum_msat: 10_000_000,
7098 fee_proportional_millionths: 0,
7099 excess_data: Vec::new()
7101 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7102 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7103 short_channel_id: 1,
7106 cltv_expiry_delta: 42,
7107 htlc_minimum_msat: 1_000,
7108 htlc_maximum_msat: 10_000_000,
7110 fee_proportional_millionths: 0,
7111 excess_data: Vec::new()
7113 let first_hops = vec![
7114 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7116 let blinded_path = BlindedPath {
7117 introduction_node_id: nodes[1],
7118 blinding_point: ln_test_utils::pubkey(42),
7120 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7121 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7124 let blinded_payinfo = BlindedPayInfo {
7125 fee_base_msat: 1000,
7126 fee_proportional_millionths: 0,
7127 htlc_minimum_msat: 1000,
7128 htlc_maximum_msat: MAX_VALUE_MSAT,
7129 cltv_expiry_delta: 0,
7130 features: BlindedHopFeatures::empty(),
7132 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7134 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7136 let netgraph = network_graph.read_only();
7137 let route_params = RouteParameters::from_payment_params_and_value(
7138 payment_params.clone(), amt_msat);
7139 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7140 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7141 &Default::default(), &random_seed_bytes) {
7142 assert_eq!(err, "Failed to find a path to the given destination");
7143 } else { panic!("Expected error") }
7145 // Sending an exact amount accounting for the blinded path fee works.
7146 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7147 let route_params = RouteParameters::from_payment_params_and_value(
7148 payment_params, amt_minus_blinded_path_fee);
7149 let route = get_route(&nodes[0], &route_params, &netgraph,
7150 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7151 &Default::default(), &random_seed_bytes).unwrap();
7152 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7153 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7157 fn direct_to_matching_intro_nodes() {
7158 // This previously caused us to enter `unreachable` code in the following situation:
7159 // 1. We add a route candidate for intro_node contributing a high amount
7160 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7161 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7162 // amount, and update our route candidate for intro_node for the lower amount
7163 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7164 // lower contribution amount, but fail (this was previously caused by failure to account for
7165 // blinded path fees when adding first_hop<>intro_node candidates)
7166 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7167 // candidate still thinks its path is contributing the original higher amount. This caused us
7168 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7170 let secp_ctx = Secp256k1::new();
7171 let logger = Arc::new(ln_test_utils::TestLogger::new());
7172 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7173 let scorer = ln_test_utils::TestScorer::new();
7174 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7175 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7176 let config = UserConfig::default();
7178 // Values are taken from the fuzz input that uncovered this panic.
7179 let amt_msat = 21_7020_5185_1403_2640;
7180 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7181 let first_hops = vec![
7182 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7183 18446744073709551615)];
7185 let blinded_path = BlindedPath {
7186 introduction_node_id: nodes[1],
7187 blinding_point: ln_test_utils::pubkey(42),
7189 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7190 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7193 let blinded_payinfo = BlindedPayInfo {
7194 fee_base_msat: 5046_2720,
7195 fee_proportional_millionths: 0,
7196 htlc_minimum_msat: 4503_5996_2737_0496,
7197 htlc_maximum_msat: 45_0359_9627_3704_9600,
7198 cltv_expiry_delta: 0,
7199 features: BlindedHopFeatures::empty(),
7201 let mut blinded_hints = vec![
7202 (blinded_payinfo.clone(), blinded_path.clone()),
7203 (blinded_payinfo.clone(), blinded_path.clone()),
7205 blinded_hints[1].0.fee_base_msat = 419_4304;
7206 blinded_hints[1].0.fee_proportional_millionths = 257;
7207 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7208 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7209 blinded_hints[1].0.cltv_expiry_delta = 0;
7211 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7212 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7213 .with_bolt12_features(bolt12_features.clone()).unwrap();
7215 let netgraph = network_graph.read_only();
7216 let route_params = RouteParameters::from_payment_params_and_value(
7217 payment_params, amt_msat);
7218 let route = get_route(&nodes[0], &route_params, &netgraph,
7219 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7220 &Default::default(), &random_seed_bytes).unwrap();
7221 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7222 assert_eq!(route.get_total_amount(), amt_msat);
7226 fn we_are_intro_node_candidate_hops() {
7227 // This previously led to a panic in the router because we'd generate a Path with only a
7228 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7229 // where the origin node is the intro node. We now fully disallow considering candidate hops
7230 // where the origin node is the intro node.
7231 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7232 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7233 let scorer = ln_test_utils::TestScorer::new();
7234 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7235 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7236 let config = UserConfig::default();
7238 // Values are taken from the fuzz input that uncovered this panic.
7239 let amt_msat = 21_7020_5185_1423_0019;
7241 let blinded_path = BlindedPath {
7242 introduction_node_id: our_id,
7243 blinding_point: ln_test_utils::pubkey(42),
7245 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7246 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7249 let blinded_payinfo = BlindedPayInfo {
7250 fee_base_msat: 5052_9027,
7251 fee_proportional_millionths: 0,
7252 htlc_minimum_msat: 21_7020_5185_1423_0019,
7253 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7254 cltv_expiry_delta: 0,
7255 features: BlindedHopFeatures::empty(),
7257 let mut blinded_hints = vec![
7258 (blinded_payinfo.clone(), blinded_path.clone()),
7259 (blinded_payinfo.clone(), blinded_path.clone()),
7261 blinded_hints[1].1.introduction_node_id = nodes[6];
7263 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7264 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7265 .with_bolt12_features(bolt12_features.clone()).unwrap();
7267 let netgraph = network_graph.read_only();
7268 let route_params = RouteParameters::from_payment_params_and_value(
7269 payment_params, amt_msat);
7270 if let Err(LightningError { err, .. }) = get_route(
7271 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7273 assert_eq!(err, "Failed to find a path to the given destination");
7278 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7279 // This previously led to a debug panic in the router because we'd find an invalid Path with
7280 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7281 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7282 // the payment, when it was intended to only include the final value of the payment.
7283 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7284 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7285 let scorer = ln_test_utils::TestScorer::new();
7286 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7287 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7288 let config = UserConfig::default();
7290 // Values are taken from the fuzz input that uncovered this panic.
7291 let amt_msat = 21_7020_5185_1423_0019;
7293 let blinded_path = BlindedPath {
7294 introduction_node_id: our_id,
7295 blinding_point: ln_test_utils::pubkey(42),
7297 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7298 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7301 let blinded_payinfo = BlindedPayInfo {
7302 fee_base_msat: 10_4425_1395,
7303 fee_proportional_millionths: 0,
7304 htlc_minimum_msat: 21_7301_9934_9094_0931,
7305 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7306 cltv_expiry_delta: 0,
7307 features: BlindedHopFeatures::empty(),
7309 let mut blinded_hints = vec![
7310 (blinded_payinfo.clone(), blinded_path.clone()),
7311 (blinded_payinfo.clone(), blinded_path.clone()),
7312 (blinded_payinfo.clone(), blinded_path.clone()),
7314 blinded_hints[1].0.fee_base_msat = 5052_9027;
7315 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7316 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7318 blinded_hints[2].1.introduction_node_id = nodes[6];
7320 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7321 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7322 .with_bolt12_features(bolt12_features.clone()).unwrap();
7324 let netgraph = network_graph.read_only();
7325 let route_params = RouteParameters::from_payment_params_and_value(
7326 payment_params, amt_msat);
7327 if let Err(LightningError { err, .. }) = get_route(
7328 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7330 assert_eq!(err, "Failed to find a path to the given destination");
7335 fn min_htlc_overpay_violates_max_htlc() {
7336 do_min_htlc_overpay_violates_max_htlc(true);
7337 do_min_htlc_overpay_violates_max_htlc(false);
7339 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7340 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7341 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7342 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7343 // that the used liquidity for a hop was less than its available liquidity limit.
7344 let secp_ctx = Secp256k1::new();
7345 let logger = Arc::new(ln_test_utils::TestLogger::new());
7346 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7347 let scorer = ln_test_utils::TestScorer::new();
7348 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7349 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7350 let config = UserConfig::default();
7352 // Values are taken from the fuzz input that uncovered this panic.
7353 let amt_msat = 7_4009_8048;
7354 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7355 let first_hop_outbound_capacity = 2_7345_2000;
7356 let first_hops = vec![get_channel_details(
7357 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7358 first_hop_outbound_capacity
7361 let base_fee = 1_6778_3453;
7362 let htlc_min = 2_5165_8240;
7363 let payment_params = if blinded_payee {
7364 let blinded_path = BlindedPath {
7365 introduction_node_id: nodes[0],
7366 blinding_point: ln_test_utils::pubkey(42),
7368 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7369 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7372 let blinded_payinfo = BlindedPayInfo {
7373 fee_base_msat: base_fee,
7374 fee_proportional_millionths: 0,
7375 htlc_minimum_msat: htlc_min,
7376 htlc_maximum_msat: htlc_min * 1000,
7377 cltv_expiry_delta: 0,
7378 features: BlindedHopFeatures::empty(),
7380 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7381 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7382 .with_bolt12_features(bolt12_features.clone()).unwrap()
7384 let route_hint = RouteHint(vec![RouteHintHop {
7385 src_node_id: nodes[0],
7386 short_channel_id: 42,
7388 base_msat: base_fee,
7389 proportional_millionths: 0,
7391 cltv_expiry_delta: 10,
7392 htlc_minimum_msat: Some(htlc_min),
7393 htlc_maximum_msat: None,
7396 PaymentParameters::from_node_id(nodes[1], 42)
7397 .with_route_hints(vec![route_hint]).unwrap()
7398 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7401 let netgraph = network_graph.read_only();
7402 let route_params = RouteParameters::from_payment_params_and_value(
7403 payment_params, amt_msat);
7404 if let Err(LightningError { err, .. }) = get_route(
7405 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7406 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7408 assert_eq!(err, "Failed to find a path to the given destination");
7413 fn previously_used_liquidity_violates_max_htlc() {
7414 do_previously_used_liquidity_violates_max_htlc(true);
7415 do_previously_used_liquidity_violates_max_htlc(false);
7418 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7419 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7420 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7421 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7422 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7423 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7424 let secp_ctx = Secp256k1::new();
7425 let logger = Arc::new(ln_test_utils::TestLogger::new());
7426 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7427 let scorer = ln_test_utils::TestScorer::new();
7428 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7429 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7430 let config = UserConfig::default();
7432 // Values are taken from the fuzz input that uncovered this panic.
7433 let amt_msat = 52_4288;
7434 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7435 let first_hops = vec![get_channel_details(
7436 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7437 ), get_channel_details(
7438 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7441 let base_fees = [0, 425_9840, 0, 0];
7442 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7443 let payment_params = if blinded_payee {
7444 let blinded_path = BlindedPath {
7445 introduction_node_id: nodes[0],
7446 blinding_point: ln_test_utils::pubkey(42),
7448 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7449 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7452 let mut blinded_hints = Vec::new();
7453 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7454 blinded_hints.push((BlindedPayInfo {
7455 fee_base_msat: *base_fee,
7456 fee_proportional_millionths: 0,
7457 htlc_minimum_msat: *htlc_min,
7458 htlc_maximum_msat: htlc_min * 100,
7459 cltv_expiry_delta: 10,
7460 features: BlindedHopFeatures::empty(),
7461 }, blinded_path.clone()));
7463 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7464 PaymentParameters::blinded(blinded_hints.clone())
7465 .with_bolt12_features(bolt12_features.clone()).unwrap()
7467 let mut route_hints = Vec::new();
7468 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7469 route_hints.push(RouteHint(vec![RouteHintHop {
7470 src_node_id: nodes[0],
7471 short_channel_id: 42 + idx as u64,
7473 base_msat: *base_fee,
7474 proportional_millionths: 0,
7476 cltv_expiry_delta: 10,
7477 htlc_minimum_msat: Some(*htlc_min),
7478 htlc_maximum_msat: Some(htlc_min * 100),
7481 PaymentParameters::from_node_id(nodes[1], 42)
7482 .with_route_hints(route_hints).unwrap()
7483 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7486 let netgraph = network_graph.read_only();
7487 let route_params = RouteParameters::from_payment_params_and_value(
7488 payment_params, amt_msat);
7490 let route = get_route(
7491 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7492 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7494 assert_eq!(route.paths.len(), 1);
7495 assert_eq!(route.get_total_amount(), amt_msat);
7499 fn candidate_path_min() {
7500 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7501 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7502 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7503 // would add a connecting first_hop node that did not have enough contribution amount, leading
7504 // to a debug panic upon invalid path construction.
7505 let secp_ctx = Secp256k1::new();
7506 let logger = Arc::new(ln_test_utils::TestLogger::new());
7507 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7508 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7509 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7510 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7511 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7512 let config = UserConfig::default();
7514 // Values are taken from the fuzz input that uncovered this panic.
7515 let amt_msat = 7_4009_8048;
7516 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7517 let first_hops = vec![get_channel_details(
7518 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7521 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7522 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7523 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7524 short_channel_id: 6,
7527 cltv_expiry_delta: (6 << 4) | 0,
7528 htlc_minimum_msat: 0,
7529 htlc_maximum_msat: MAX_VALUE_MSAT,
7531 fee_proportional_millionths: 0,
7532 excess_data: Vec::new()
7534 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7536 let htlc_min = 2_5165_8240;
7537 let blinded_hints = vec![
7539 fee_base_msat: 1_6778_3453,
7540 fee_proportional_millionths: 0,
7541 htlc_minimum_msat: htlc_min,
7542 htlc_maximum_msat: htlc_min * 100,
7543 cltv_expiry_delta: 10,
7544 features: BlindedHopFeatures::empty(),
7546 introduction_node_id: nodes[0],
7547 blinding_point: ln_test_utils::pubkey(42),
7549 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7550 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7554 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7555 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7556 .with_bolt12_features(bolt12_features.clone()).unwrap();
7557 let route_params = RouteParameters::from_payment_params_and_value(
7558 payment_params, amt_msat);
7559 let netgraph = network_graph.read_only();
7561 if let Err(LightningError { err, .. }) = get_route(
7562 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7563 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7566 assert_eq!(err, "Failed to find a path to the given destination");
7571 fn path_contribution_includes_min_htlc_overpay() {
7572 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7573 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7574 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7575 // selection, both tested here.
7576 let secp_ctx = Secp256k1::new();
7577 let logger = Arc::new(ln_test_utils::TestLogger::new());
7578 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7579 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7580 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7581 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7582 let config = UserConfig::default();
7584 // Values are taken from the fuzz input that uncovered this panic.
7585 let amt_msat = 562_0000;
7586 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7587 let first_hops = vec![
7588 get_channel_details(
7589 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7593 let htlc_mins = [49_0000, 1125_0000];
7594 let payment_params = {
7595 let blinded_path = BlindedPath {
7596 introduction_node_id: nodes[0],
7597 blinding_point: ln_test_utils::pubkey(42),
7599 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7600 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7603 let mut blinded_hints = Vec::new();
7604 for htlc_min in htlc_mins.iter() {
7605 blinded_hints.push((BlindedPayInfo {
7607 fee_proportional_millionths: 0,
7608 htlc_minimum_msat: *htlc_min,
7609 htlc_maximum_msat: *htlc_min * 100,
7610 cltv_expiry_delta: 10,
7611 features: BlindedHopFeatures::empty(),
7612 }, blinded_path.clone()));
7614 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7615 PaymentParameters::blinded(blinded_hints.clone())
7616 .with_bolt12_features(bolt12_features.clone()).unwrap()
7619 let netgraph = network_graph.read_only();
7620 let route_params = RouteParameters::from_payment_params_and_value(
7621 payment_params, amt_msat);
7622 let route = get_route(
7623 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7624 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7627 assert_eq!(route.paths.len(), 1);
7628 assert_eq!(route.get_total_amount(), amt_msat);
7632 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7633 pub(crate) mod bench_utils {
7637 use bitcoin::hashes::Hash;
7638 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7640 use crate::chain::transaction::OutPoint;
7641 use crate::routing::scoring::ScoreUpdate;
7642 use crate::sign::{EntropySource, KeysManager};
7643 use crate::ln::ChannelId;
7644 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7645 use crate::ln::features::Bolt11InvoiceFeatures;
7646 use crate::routing::gossip::NetworkGraph;
7647 use crate::util::config::UserConfig;
7648 use crate::util::ser::ReadableArgs;
7649 use crate::util::test_utils::TestLogger;
7651 /// Tries to open a network graph file, or panics with a URL to fetch it.
7652 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7653 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7654 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7655 .or_else(|_| { // Fall back to guessing based on the binary location
7656 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7657 let mut path = std::env::current_exe().unwrap();
7658 path.pop(); // lightning-...
7660 path.pop(); // debug
7661 path.pop(); // target
7662 path.push("lightning");
7663 path.push("net_graph-2023-01-18.bin");
7666 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7667 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7668 let mut path = std::env::current_exe().unwrap();
7669 path.pop(); // bench...
7671 path.pop(); // debug
7672 path.pop(); // target
7673 path.pop(); // bench
7674 path.push("lightning");
7675 path.push("net_graph-2023-01-18.bin");
7678 .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");
7679 #[cfg(require_route_graph_test)]
7680 return Ok(res.unwrap());
7681 #[cfg(not(require_route_graph_test))]
7685 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7686 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7689 pub(crate) fn payer_pubkey() -> PublicKey {
7690 let secp_ctx = Secp256k1::new();
7691 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7695 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7697 channel_id: ChannelId::new_zero(),
7698 counterparty: ChannelCounterparty {
7699 features: channelmanager::provided_init_features(&UserConfig::default()),
7701 unspendable_punishment_reserve: 0,
7702 forwarding_info: None,
7703 outbound_htlc_minimum_msat: None,
7704 outbound_htlc_maximum_msat: None,
7706 funding_txo: Some(OutPoint {
7707 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7710 short_channel_id: Some(1),
7711 inbound_scid_alias: None,
7712 outbound_scid_alias: None,
7713 channel_value_satoshis: 10_000_000_000,
7715 outbound_capacity_msat: 10_000_000_000,
7716 next_outbound_htlc_minimum_msat: 0,
7717 next_outbound_htlc_limit_msat: 10_000_000_000,
7718 inbound_capacity_msat: 0,
7719 unspendable_punishment_reserve: None,
7720 confirmations_required: None,
7721 confirmations: None,
7722 force_close_spend_delay: None,
7724 is_channel_ready: true,
7727 inbound_htlc_minimum_msat: None,
7728 inbound_htlc_maximum_msat: None,
7730 feerate_sat_per_1000_weight: None,
7731 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7735 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7736 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7737 starting_amount: u64, route_count: usize,
7738 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7739 let payer = payer_pubkey();
7740 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7741 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7743 let nodes = graph.read_only().nodes().clone();
7744 let mut route_endpoints = Vec::new();
7745 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7746 // with some routes we picked being un-routable.
7747 for _ in 0..route_count * 3 / 2 {
7749 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7750 let src = PublicKey::from_slice(nodes.unordered_keys()
7751 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7752 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7753 let dst = PublicKey::from_slice(nodes.unordered_keys()
7754 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7755 let params = PaymentParameters::from_node_id(dst, 42)
7756 .with_bolt11_features(features.clone()).unwrap();
7757 let first_hop = first_hop(src);
7758 let amt_msat = starting_amount + seed % 1_000_000;
7759 let route_params = RouteParameters::from_payment_params_and_value(
7760 params.clone(), amt_msat);
7762 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7763 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7765 // ...and seed the scorer with success and failure data...
7766 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7767 let mut score_amt = seed % 1_000_000_000;
7769 // Generate fail/success paths for a wider range of potential amounts with
7770 // MPP enabled to give us a chance to apply penalties for more potential
7772 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7773 let params = PaymentParameters::from_node_id(dst, 42)
7774 .with_bolt11_features(mpp_features).unwrap();
7775 let route_params = RouteParameters::from_payment_params_and_value(
7776 params.clone(), score_amt);
7777 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7778 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7779 &random_seed_bytes);
7780 if let Ok(route) = route_res {
7781 for path in route.paths {
7782 if seed & 0x80 == 0 {
7783 scorer.payment_path_successful(&path);
7785 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7786 scorer.payment_path_failed(&path, short_channel_id);
7788 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7792 // If we couldn't find a path with a higer amount, reduce and try again.
7796 route_endpoints.push((first_hop, params, amt_msat));
7802 // Because we've changed channel scores, it's possible we'll take different routes to the
7803 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7804 // requires a too-high CLTV delta.
7805 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7806 let route_params = RouteParameters::from_payment_params_and_value(
7807 params.clone(), *amt_msat);
7808 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7809 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7811 route_endpoints.truncate(route_count);
7812 assert_eq!(route_endpoints.len(), route_count);
7820 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7821 use crate::sign::{EntropySource, KeysManager};
7822 use crate::ln::channelmanager;
7823 use crate::ln::features::Bolt11InvoiceFeatures;
7824 use crate::routing::gossip::NetworkGraph;
7825 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7826 use crate::util::config::UserConfig;
7827 use crate::util::logger::{Logger, Record};
7828 use crate::util::test_utils::TestLogger;
7830 use criterion::Criterion;
7832 struct DummyLogger {}
7833 impl Logger for DummyLogger {
7834 fn log(&self, _record: &Record) {}
7837 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7838 let logger = TestLogger::new();
7839 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7840 let scorer = FixedPenaltyScorer::with_penalty(0);
7841 generate_routes(bench, &network_graph, scorer, &Default::default(),
7842 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
7845 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7846 let logger = TestLogger::new();
7847 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7848 let scorer = FixedPenaltyScorer::with_penalty(0);
7849 generate_routes(bench, &network_graph, scorer, &Default::default(),
7850 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7851 "generate_mpp_routes_with_zero_penalty_scorer");
7854 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7855 let logger = TestLogger::new();
7856 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7857 let params = ProbabilisticScoringFeeParameters::default();
7858 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7859 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7860 "generate_routes_with_probabilistic_scorer");
7863 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7864 let logger = TestLogger::new();
7865 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7866 let params = ProbabilisticScoringFeeParameters::default();
7867 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7868 generate_routes(bench, &network_graph, scorer, ¶ms,
7869 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7870 "generate_mpp_routes_with_probabilistic_scorer");
7873 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7874 let logger = TestLogger::new();
7875 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7876 let params = ProbabilisticScoringFeeParameters::default();
7877 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7878 generate_routes(bench, &network_graph, scorer, ¶ms,
7879 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7880 "generate_large_mpp_routes_with_probabilistic_scorer");
7883 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7884 let logger = TestLogger::new();
7885 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7886 let mut params = ProbabilisticScoringFeeParameters::default();
7887 params.linear_success_probability = false;
7888 let scorer = ProbabilisticScorer::new(
7889 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7890 generate_routes(bench, &network_graph, scorer, ¶ms,
7891 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7892 "generate_routes_with_nonlinear_probabilistic_scorer");
7895 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7896 let logger = TestLogger::new();
7897 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7898 let mut params = ProbabilisticScoringFeeParameters::default();
7899 params.linear_success_probability = false;
7900 let scorer = ProbabilisticScorer::new(
7901 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7902 generate_routes(bench, &network_graph, scorer, ¶ms,
7903 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7904 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
7907 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7908 let logger = TestLogger::new();
7909 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7910 let mut params = ProbabilisticScoringFeeParameters::default();
7911 params.linear_success_probability = false;
7912 let scorer = ProbabilisticScorer::new(
7913 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7914 generate_routes(bench, &network_graph, scorer, ¶ms,
7915 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7916 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
7919 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7920 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7921 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7922 bench_name: &'static str,
7924 let payer = bench_utils::payer_pubkey();
7925 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7926 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7928 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7929 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7931 // ...then benchmark finding paths between the nodes we learned.
7933 bench.bench_function(bench_name, |b| b.iter(|| {
7934 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
7935 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
7936 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7937 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());