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 = 0;
1717 let mut num_ignored_path_length_limit = 0;
1718 let mut num_ignored_cltv_delta_limit = 0;
1719 let mut num_ignored_previously_failed = 0;
1720 let mut num_ignored_total_fee_limit = 0;
1722 macro_rules! add_entry {
1723 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1724 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1725 // since that value has to be transferred over this channel.
1726 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1727 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1728 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1729 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1730 // We "return" whether we updated the path at the end, and how much we can route via
1731 // this channel, via this:
1732 let mut hop_contribution_amt_msat = None;
1733 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1734 // practice these cases should be caught earlier:
1735 // - for regular channels at channel announcement (TODO)
1736 // - for first and last hops early in get_route
1737 if $src_node_id != $dest_node_id {
1738 let scid_opt = $candidate.short_channel_id();
1739 let effective_capacity = $candidate.effective_capacity();
1740 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1742 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1743 // It may be misleading because we might later choose to reduce the value transferred
1744 // over these channels, and the channel which was insufficient might become sufficient.
1745 // Worst case: we drop a good channel here because it can't cover the high following
1746 // fees caused by one expensive channel, but then this channel could have been used
1747 // if the amount being transferred over this path is lower.
1748 // We do this for now, but this is a subject for removal.
1749 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1750 let used_liquidity_msat = used_liquidities
1751 .get(&$candidate.id($src_node_id < $dest_node_id))
1752 .map_or(0, |used_liquidity_msat| {
1753 available_value_contribution_msat = available_value_contribution_msat
1754 .saturating_sub(*used_liquidity_msat);
1755 *used_liquidity_msat
1758 // Verify the liquidity offered by this channel complies to the minimal contribution.
1759 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1760 // Do not consider candidate hops that would exceed the maximum path length.
1761 let path_length_to_node = $next_hops_path_length + 1;
1762 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1764 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1765 // In order to already account for some of the privacy enhancing random CLTV
1766 // expiry delta offset we add on top later, we subtract a rough estimate
1767 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1768 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1769 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1770 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1771 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1772 .saturating_add($candidate.cltv_expiry_delta());
1773 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1775 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1776 // Includes paying fees for the use of the following channels.
1777 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1778 Some(result) => result,
1779 // Can't overflow due to how the values were computed right above.
1780 None => unreachable!(),
1782 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1783 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1784 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1786 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1787 let may_overpay_to_meet_path_minimum_msat =
1788 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1789 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1790 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1791 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1793 let payment_failed_on_this_channel = scid_opt.map_or(false,
1794 |scid| payment_params.previously_failed_channels.contains(&scid));
1796 let should_log_candidate = match $candidate {
1797 CandidateRouteHop::FirstHop { .. } => true,
1798 CandidateRouteHop::PrivateHop { .. } => true,
1799 CandidateRouteHop::Blinded { .. } => true,
1800 CandidateRouteHop::OneHopBlinded { .. } => true,
1804 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1805 // bother considering this channel. If retrying with recommended_value_msat may
1806 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1807 // around again with a higher amount.
1808 if !contributes_sufficient_value {
1809 if should_log_candidate {
1810 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1812 num_ignored_value_contribution += 1;
1813 } else if exceeds_max_path_length {
1814 if should_log_candidate {
1815 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1817 num_ignored_path_length_limit += 1;
1818 } else if exceeds_cltv_delta_limit {
1819 if should_log_candidate {
1820 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1822 num_ignored_cltv_delta_limit += 1;
1823 } else if payment_failed_on_this_channel {
1824 if should_log_candidate {
1825 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1827 num_ignored_previously_failed += 1;
1828 } else if may_overpay_to_meet_path_minimum_msat {
1829 hit_minimum_limit = true;
1830 } else if over_path_minimum_msat {
1831 // Note that low contribution here (limited by available_liquidity_msat)
1832 // might violate htlc_minimum_msat on the hops which are next along the
1833 // payment path (upstream to the payee). To avoid that, we recompute
1834 // path fees knowing the final path contribution after constructing it.
1835 let curr_min = cmp::max(
1836 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
1838 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
1839 .saturating_add(curr_min);
1840 let hm_entry = dist.entry($src_node_id);
1841 let old_entry = hm_entry.or_insert_with(|| {
1842 // If there was previously no known way to access the source node
1843 // (recall it goes payee-to-payer) of short_channel_id, first add a
1844 // semi-dummy record just to compute the fees to reach the source node.
1845 // This will affect our decision on selecting short_channel_id
1846 // as a way to reach the $dest_node_id.
1848 node_id: $dest_node_id.clone(),
1849 candidate: $candidate.clone(),
1851 next_hops_fee_msat: u64::max_value(),
1852 hop_use_fee_msat: u64::max_value(),
1853 total_fee_msat: u64::max_value(),
1854 path_htlc_minimum_msat,
1855 path_penalty_msat: u64::max_value(),
1856 was_processed: false,
1857 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1858 value_contribution_msat,
1862 #[allow(unused_mut)] // We only use the mut in cfg(test)
1863 let mut should_process = !old_entry.was_processed;
1864 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1866 // In test/fuzzing builds, we do extra checks to make sure the skipping
1867 // of already-seen nodes only happens in cases we expect (see below).
1868 if !should_process { should_process = true; }
1872 let mut hop_use_fee_msat = 0;
1873 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1875 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1876 // will have the same effective-fee
1877 if $src_node_id != our_node_id {
1878 // Note that `u64::max_value` means we'll always fail the
1879 // `old_entry.total_fee_msat > total_fee_msat` check below
1880 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1881 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1884 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
1885 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1886 if total_fee_msat > max_total_routing_fee_msat {
1887 if should_log_candidate {
1888 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
1890 num_ignored_total_fee_limit += 1;
1892 let channel_usage = ChannelUsage {
1893 amount_msat: amount_to_transfer_over_msat,
1894 inflight_htlc_msat: used_liquidity_msat,
1897 let channel_penalty_msat = scid_opt.map_or(0,
1898 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1899 channel_usage, score_params));
1900 let path_penalty_msat = $next_hops_path_penalty_msat
1901 .saturating_add(channel_penalty_msat);
1902 let new_graph_node = RouteGraphNode {
1903 node_id: $src_node_id,
1904 lowest_fee_to_node: total_fee_msat,
1905 total_cltv_delta: hop_total_cltv_delta,
1906 value_contribution_msat,
1907 path_htlc_minimum_msat,
1909 path_length_to_node,
1912 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1913 // if this way is cheaper than the already known
1914 // (considering the cost to "reach" this channel from the route destination,
1915 // the cost of using this channel,
1916 // and the cost of routing to the source node of this channel).
1917 // Also, consider that htlc_minimum_msat_difference, because we might end up
1918 // paying it. Consider the following exploit:
1919 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1920 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1921 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1922 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1924 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1925 // but it may require additional tracking - we don't want to double-count
1926 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1927 // can't use something that may decrease on future hops.
1928 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1929 .saturating_add(old_entry.path_penalty_msat);
1930 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1931 .saturating_add(path_penalty_msat);
1933 if !old_entry.was_processed && new_cost < old_cost {
1934 targets.push(new_graph_node);
1935 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1936 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1937 old_entry.total_fee_msat = total_fee_msat;
1938 old_entry.node_id = $dest_node_id.clone();
1939 old_entry.candidate = $candidate.clone();
1940 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1941 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1942 old_entry.path_penalty_msat = path_penalty_msat;
1943 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1945 old_entry.value_contribution_msat = value_contribution_msat;
1947 hop_contribution_amt_msat = Some(value_contribution_msat);
1948 } else if old_entry.was_processed && new_cost < old_cost {
1949 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1951 // If we're skipping processing a node which was previously
1952 // processed even though we found another path to it with a
1953 // cheaper fee, check that it was because the second path we
1954 // found (which we are processing now) has a lower value
1955 // contribution due to an HTLC minimum limit.
1957 // e.g. take a graph with two paths from node 1 to node 2, one
1958 // through channel A, and one through channel B. Channel A and
1959 // B are both in the to-process heap, with their scores set by
1960 // a higher htlc_minimum than fee.
1961 // Channel A is processed first, and the channels onwards from
1962 // node 1 are added to the to-process heap. Thereafter, we pop
1963 // Channel B off of the heap, note that it has a much more
1964 // restrictive htlc_maximum_msat, and recalculate the fees for
1965 // all of node 1's channels using the new, reduced, amount.
1967 // This would be bogus - we'd be selecting a higher-fee path
1968 // with a lower htlc_maximum_msat instead of the one we'd
1969 // already decided to use.
1970 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1972 value_contribution_msat + path_penalty_msat <
1973 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1982 hop_contribution_amt_msat
1986 let default_node_features = default_node_features();
1988 // Find ways (channels with destination) to reach a given node and store them
1989 // in the corresponding data structures (routing graph etc).
1990 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1991 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1992 // This data can later be helpful to optimize routing (pay lower fees).
1993 macro_rules! add_entries_to_cheapest_to_target_node {
1994 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1995 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1996 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1997 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1998 let was_processed = elem.was_processed;
1999 elem.was_processed = true;
2002 // Entries are added to dist in add_entry!() when there is a channel from a node.
2003 // Because there are no channels from payee, it will not have a dist entry at this point.
2004 // If we're processing any other node, it is always be the result of a channel from it.
2005 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2010 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2011 for details in first_channels {
2012 let candidate = CandidateRouteHop::FirstHop { details };
2013 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
2014 $next_hops_value_contribution,
2015 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
2016 $next_hops_cltv_delta, $next_hops_path_length);
2020 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2023 &default_node_features
2026 if !features.requires_unknown_bits() {
2027 for chan_id in $node.channels.iter() {
2028 let chan = network_channels.get(chan_id).unwrap();
2029 if !chan.features.requires_unknown_bits() {
2030 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2031 if first_hops.is_none() || *source != our_node_id {
2032 if directed_channel.direction().enabled {
2033 let candidate = CandidateRouteHop::PublicHop {
2034 info: directed_channel,
2035 short_channel_id: *chan_id,
2037 add_entry!(candidate, *source, $node_id,
2038 $fee_to_target_msat,
2039 $next_hops_value_contribution,
2040 $next_hops_path_htlc_minimum_msat,
2041 $next_hops_path_penalty_msat,
2042 $next_hops_cltv_delta, $next_hops_path_length);
2053 let mut payment_paths = Vec::<PaymentPath>::new();
2055 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2056 'paths_collection: loop {
2057 // For every new path, start from scratch, except for used_liquidities, which
2058 // helps to avoid reusing previously selected paths in future iterations.
2061 hit_minimum_limit = false;
2063 // If first hop is a private channel and the only way to reach the payee, this is the only
2064 // place where it could be added.
2065 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2066 for details in first_channels {
2067 let candidate = CandidateRouteHop::FirstHop { details };
2068 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
2069 0, 0u64, 0, 0).is_some();
2070 log_trace!(logger, "{} direct route to payee via {}",
2071 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2075 // Add the payee as a target, so that the payee-to-payer
2076 // search algorithm knows what to start with.
2077 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2078 // The payee is not in our network graph, so nothing to add here.
2079 // There is still a chance of reaching them via last_hops though,
2080 // so don't yet fail the payment here.
2081 // If not, targets.pop() will not even let us enter the loop in step 2.
2084 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2089 // If a caller provided us with last hops, add them to routing targets. Since this happens
2090 // earlier than general path finding, they will be somewhat prioritized, although currently
2091 // it matters only if the fees are exactly the same.
2092 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2093 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2094 let have_intro_node_in_graph =
2095 // Only add the hops in this route to our candidate set if either
2096 // we have a direct channel to the first hop or the first hop is
2097 // in the regular network graph.
2098 first_hop_targets.get(&intro_node_id).is_some() ||
2099 network_nodes.get(&intro_node_id).is_some();
2100 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2101 let candidate = if hint.1.blinded_hops.len() == 1 {
2102 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2103 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2104 let mut path_contribution_msat = path_value_msat;
2105 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2106 0, path_contribution_msat, 0, 0_u64, 0, 0)
2108 path_contribution_msat = hop_used_msat;
2110 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2111 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2113 for details in first_channels {
2114 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2115 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2119 let path_min = candidate.htlc_minimum_msat().saturating_add(
2120 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2121 add_entry!(first_hop_candidate, our_node_id, intro_node_id, blinded_path_fee,
2122 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2123 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2127 for route in payment_params.payee.unblinded_route_hints().iter()
2128 .filter(|route| !route.0.is_empty())
2130 let first_hop_in_route = &(route.0)[0];
2131 let have_hop_src_in_graph =
2132 // Only add the hops in this route to our candidate set if either
2133 // we have a direct channel to the first hop or the first hop is
2134 // in the regular network graph.
2135 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
2136 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
2137 if have_hop_src_in_graph {
2138 // We start building the path from reverse, i.e., from payee
2139 // to the first RouteHintHop in the path.
2140 let hop_iter = route.0.iter().rev();
2141 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2142 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2143 let mut hop_used = true;
2144 let mut aggregate_next_hops_fee_msat: u64 = 0;
2145 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2146 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2147 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2148 let mut aggregate_next_hops_path_length: u8 = 0;
2149 let mut aggregate_path_contribution_msat = path_value_msat;
2151 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2152 let source = NodeId::from_pubkey(&hop.src_node_id);
2153 let target = NodeId::from_pubkey(&prev_hop_id);
2154 let candidate = network_channels
2155 .get(&hop.short_channel_id)
2156 .and_then(|channel| channel.as_directed_to(&target))
2157 .map(|(info, _)| CandidateRouteHop::PublicHop {
2159 short_channel_id: hop.short_channel_id,
2161 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2163 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2164 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2165 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2166 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2168 aggregate_path_contribution_msat = hop_used_msat;
2170 // If this hop was not used then there is no use checking the preceding
2171 // hops in the RouteHint. We can break by just searching for a direct
2172 // channel between last checked hop and first_hop_targets.
2176 let used_liquidity_msat = used_liquidities
2177 .get(&candidate.id(source < target)).copied()
2179 let channel_usage = ChannelUsage {
2180 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2181 inflight_htlc_msat: used_liquidity_msat,
2182 effective_capacity: candidate.effective_capacity(),
2184 let channel_penalty_msat = scorer.channel_penalty_msat(
2185 hop.short_channel_id, &source, &target, channel_usage, score_params
2187 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2188 .saturating_add(channel_penalty_msat);
2190 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2191 .saturating_add(hop.cltv_expiry_delta as u32);
2193 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2196 // Searching for a direct channel between last checked hop and first_hop_targets
2197 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&prev_hop_id)) {
2198 sort_first_hop_channels(first_channels, &used_liquidities,
2199 recommended_value_msat, our_node_pubkey);
2200 for details in first_channels {
2201 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2202 add_entry!(first_hop_candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
2203 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2204 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2205 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2213 // In the next values of the iterator, the aggregate fees already reflects
2214 // the sum of value sent from payer (final_value_msat) and routing fees
2215 // for the last node in the RouteHint. We need to just add the fees to
2216 // route through the current node so that the preceding node (next iteration)
2218 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2219 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2220 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2222 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2223 // this route hint's source node to forward said min over this channel.
2224 aggregate_next_hops_path_htlc_minimum_msat = {
2225 let curr_htlc_min = cmp::max(
2226 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2228 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2229 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2232 if idx == route.0.len() - 1 {
2233 // The last hop in this iterator is the first hop in
2234 // overall RouteHint.
2235 // If this hop connects to a node with which we have a direct channel,
2236 // ignore the network graph and, if the last hop was added, add our
2237 // direct channel to the candidate set.
2239 // Note that we *must* check if the last hop was added as `add_entry`
2240 // always assumes that the third argument is a node to which we have a
2242 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2243 sort_first_hop_channels(first_channels, &used_liquidities,
2244 recommended_value_msat, our_node_pubkey);
2245 for details in first_channels {
2246 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2247 add_entry!(first_hop_candidate, our_node_id,
2248 NodeId::from_pubkey(&hop.src_node_id),
2249 aggregate_next_hops_fee_msat,
2250 aggregate_path_contribution_msat,
2251 aggregate_next_hops_path_htlc_minimum_msat,
2252 aggregate_next_hops_path_penalty_msat,
2253 aggregate_next_hops_cltv_delta,
2254 aggregate_next_hops_path_length);
2262 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2264 // At this point, targets are filled with the data from first and
2265 // last hops communicated by the caller, and the payment receiver.
2266 let mut found_new_path = false;
2269 // If this loop terminates due the exhaustion of targets, two situations are possible:
2270 // - not enough outgoing liquidity:
2271 // 0 < already_collected_value_msat < final_value_msat
2272 // - enough outgoing liquidity:
2273 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2274 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2275 // paths_collection will be stopped because found_new_path==false.
2276 // This is not necessarily a routing failure.
2277 '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() {
2279 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2280 // traversing the graph and arrange the path out of what we found.
2281 if node_id == our_node_id {
2282 let mut new_entry = dist.remove(&our_node_id).unwrap();
2283 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2286 let mut features_set = false;
2287 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2288 for details in first_channels {
2289 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2290 if details.get_outbound_payment_scid().unwrap() == scid {
2291 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2292 features_set = true;
2299 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2300 if let Some(node_info) = node.announcement_info.as_ref() {
2301 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2303 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2306 // We can fill in features for everything except hops which were
2307 // provided via the invoice we're paying. We could guess based on the
2308 // recipient's features but for now we simply avoid guessing at all.
2312 // Means we succesfully traversed from the payer to the payee, now
2313 // save this path for the payment route. Also, update the liquidity
2314 // remaining on the used hops, so that we take them into account
2315 // while looking for more paths.
2316 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2320 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2321 Some(payment_hop) => payment_hop,
2322 // We can't arrive at None because, if we ever add an entry to targets,
2323 // we also fill in the entry in dist (see add_entry!).
2324 None => unreachable!(),
2326 // We "propagate" the fees one hop backward (topologically) here,
2327 // so that fees paid for a HTLC forwarding on the current channel are
2328 // associated with the previous channel (where they will be subtracted).
2329 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2330 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2332 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2333 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2335 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2336 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2338 let mut payment_path = PaymentPath {hops: ordered_hops};
2340 // We could have possibly constructed a slightly inconsistent path: since we reduce
2341 // value being transferred along the way, we could have violated htlc_minimum_msat
2342 // on some channels we already passed (assuming dest->source direction). Here, we
2343 // recompute the fees again, so that if that's the case, we match the currently
2344 // underpaid htlc_minimum_msat with fees.
2345 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2346 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2347 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2349 // Since a path allows to transfer as much value as
2350 // the smallest channel it has ("bottleneck"), we should recompute
2351 // the fees so sender HTLC don't overpay fees when traversing
2352 // larger channels than the bottleneck. This may happen because
2353 // when we were selecting those channels we were not aware how much value
2354 // this path will transfer, and the relative fee for them
2355 // might have been computed considering a larger value.
2356 // Remember that we used these channels so that we don't rely
2357 // on the same liquidity in future paths.
2358 let mut prevented_redundant_path_selection = false;
2359 let prev_hop_iter = core::iter::once(&our_node_id)
2360 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2361 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2362 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2363 let used_liquidity_msat = used_liquidities
2364 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2365 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2366 .or_insert(spent_on_hop_msat);
2367 let hop_capacity = hop.candidate.effective_capacity();
2368 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2369 if *used_liquidity_msat == hop_max_msat {
2370 // If this path used all of this channel's available liquidity, we know
2371 // this path will not be selected again in the next loop iteration.
2372 prevented_redundant_path_selection = true;
2374 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2376 if !prevented_redundant_path_selection {
2377 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2378 // we'll probably end up picking the same path again on the next iteration.
2379 // Decrease the available liquidity of a hop in the middle of the path.
2380 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2381 let exhausted = u64::max_value();
2383 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2384 LoggedCandidateHop(victim_candidate));
2385 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2386 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2389 // Track the total amount all our collected paths allow to send so that we know
2390 // when to stop looking for more paths
2391 already_collected_value_msat += value_contribution_msat;
2393 payment_paths.push(payment_path);
2394 found_new_path = true;
2395 break 'path_construction;
2398 // If we found a path back to the payee, we shouldn't try to process it again. This is
2399 // the equivalent of the `elem.was_processed` check in
2400 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2401 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2403 // Otherwise, since the current target node is not us,
2404 // keep "unrolling" the payment graph from payee to payer by
2405 // finding a way to reach the current target from the payer side.
2406 match network_nodes.get(&node_id) {
2409 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2410 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2411 total_cltv_delta, path_length_to_node);
2417 if !found_new_path && channel_saturation_pow_half != 0 {
2418 channel_saturation_pow_half = 0;
2419 continue 'paths_collection;
2421 // If we don't support MPP, no use trying to gather more value ever.
2422 break 'paths_collection;
2426 // Stop either when the recommended value is reached or if no new path was found in this
2428 // In the latter case, making another path finding attempt won't help,
2429 // because we deterministically terminated the search due to low liquidity.
2430 if !found_new_path && channel_saturation_pow_half != 0 {
2431 channel_saturation_pow_half = 0;
2432 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2433 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2434 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2435 break 'paths_collection;
2436 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2437 // Further, if this was our first walk of the graph, and we weren't limited by an
2438 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2439 // limited by an htlc_minimum_msat value, find another path with a higher value,
2440 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2441 // still keeping a lower total fee than this path.
2442 if !hit_minimum_limit {
2443 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2444 break 'paths_collection;
2446 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
2447 path_value_msat = recommended_value_msat;
2451 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2452 num_ignored_cltv_delta_limit + num_ignored_previously_failed + num_ignored_total_fee_limit;
2453 if num_ignored_total > 0 {
2454 log_trace!(logger, "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure, {} due to maximum total fee limit. Total: {} ignored candidates.", num_ignored_value_contribution, num_ignored_path_length_limit, num_ignored_cltv_delta_limit, num_ignored_previously_failed, num_ignored_total_fee_limit, num_ignored_total);
2458 if payment_paths.len() == 0 {
2459 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2462 if already_collected_value_msat < final_value_msat {
2463 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2467 let mut selected_route = payment_paths;
2469 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2470 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2472 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2473 // the value they contribute towards the payment amount.
2474 // We sort in descending order as we will remove from the front in `retain`, next.
2475 selected_route.sort_unstable_by(|a, b|
2476 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2477 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2480 // We should make sure that at least 1 path left.
2481 let mut paths_left = selected_route.len();
2482 selected_route.retain(|path| {
2483 if paths_left == 1 {
2486 let path_value_msat = path.get_value_msat();
2487 if path_value_msat <= overpaid_value_msat {
2488 overpaid_value_msat -= path_value_msat;
2494 debug_assert!(selected_route.len() > 0);
2496 if overpaid_value_msat != 0 {
2498 // Now, subtract the remaining overpaid value from the most-expensive path.
2499 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2500 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2501 selected_route.sort_unstable_by(|a, b| {
2502 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2503 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2504 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2506 let expensive_payment_path = selected_route.first_mut().unwrap();
2508 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2509 // can't go negative.
2510 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2511 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2515 // Sort by the path itself and combine redundant paths.
2516 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2517 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2519 selected_route.sort_unstable_by_key(|path| {
2520 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2521 debug_assert!(path.hops.len() <= key.len());
2522 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2527 for idx in 0..(selected_route.len() - 1) {
2528 if idx + 1 >= selected_route.len() { break; }
2529 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2530 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2531 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2532 selected_route[idx].update_value_and_recompute_fees(new_value);
2533 selected_route.remove(idx + 1);
2537 let mut paths = Vec::new();
2538 for payment_path in selected_route {
2539 let mut hops = Vec::with_capacity(payment_path.hops.len());
2540 let mut prev_hop_node_id = our_node_id;
2541 for (hop, node_features) in payment_path.hops.iter()
2542 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2544 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2545 // If we sourced the hop from the graph we're sure the target node is announced.
2547 } else if let CandidateRouteHop::FirstHop { details } = hop.candidate {
2548 // If this is a first hop we also know if it's announced.
2551 // If we sourced it any other way, we double-check the network graph to see if
2552 // there are announced channels between the endpoints. If so, the hop might be
2553 // referring to any of the announced channels, as its `short_channel_id` might be
2554 // an alias, in which case we don't take any chances here.
2555 network_graph.node(&hop.node_id).map_or(false, |hop_node|
2556 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2557 .map_or(false, |c| c.as_directed_from(&prev_hop_node_id).is_some()))
2561 hops.push(RouteHop {
2562 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)})?,
2563 node_features: node_features.clone(),
2564 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2565 channel_features: hop.candidate.features(),
2566 fee_msat: hop.fee_msat,
2567 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2568 maybe_announced_channel,
2571 prev_hop_node_id = hop.node_id;
2573 let mut final_cltv_delta = final_cltv_expiry_delta;
2574 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2575 if let Some(blinded_path) = h.candidate.blinded_path() {
2576 final_cltv_delta = h.candidate.cltv_expiry_delta();
2578 hops: blinded_path.blinded_hops.clone(),
2579 blinding_point: blinded_path.blinding_point,
2580 excess_final_cltv_expiry_delta: 0,
2581 final_value_msat: h.fee_msat,
2585 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2586 // applicable for the previous hop.
2587 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2588 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2591 paths.push(Path { hops, blinded_tail });
2593 // Make sure we would never create a route with more paths than we allow.
2594 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2596 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2597 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2598 if paths.iter().map(|p| p.fee_msat()).sum::<u64>() > max_total_routing_fee_msat {
2599 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2600 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2604 if let Some(node_features) = payment_params.payee.node_features() {
2605 for path in paths.iter_mut() {
2606 path.hops.last_mut().unwrap().node_features = node_features.clone();
2610 let route = Route { paths, route_params: Some(route_params.clone()) };
2611 log_info!(logger, "Got route: {}", log_route!(route));
2615 // When an adversarial intermediary node observes a payment, it may be able to infer its
2616 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2617 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2618 // payment path by adding a randomized 'shadow route' offset to the final hop.
2619 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2620 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2622 let network_channels = network_graph.channels();
2623 let network_nodes = network_graph.nodes();
2625 for path in route.paths.iter_mut() {
2626 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2628 // Remember the last three nodes of the random walk and avoid looping back on them.
2629 // Init with the last three nodes from the actual path, if possible.
2630 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2631 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2632 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2634 // Choose the last publicly known node as the starting point for the random walk.
2635 let mut cur_hop: Option<NodeId> = None;
2636 let mut path_nonce = [0u8; 12];
2637 if let Some(starting_hop) = path.hops.iter().rev()
2638 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2639 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2640 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2643 // Init PRNG with the path-dependant nonce, which is static for private paths.
2644 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2645 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2647 // Pick a random path length in [1 .. 3]
2648 prng.process_in_place(&mut random_path_bytes);
2649 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2651 for random_hop in 0..random_walk_length {
2652 // If we don't find a suitable offset in the public network graph, we default to
2653 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2654 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2656 if let Some(cur_node_id) = cur_hop {
2657 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2658 // Randomly choose the next unvisited hop.
2659 prng.process_in_place(&mut random_path_bytes);
2660 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2661 .checked_rem(cur_node.channels.len())
2662 .and_then(|index| cur_node.channels.get(index))
2663 .and_then(|id| network_channels.get(id)) {
2664 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2665 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2666 nodes_to_avoid[random_hop] = *next_id;
2667 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2668 cur_hop = Some(*next_id);
2675 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2676 .checked_add(random_hop_offset)
2677 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2680 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2681 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2682 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2684 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2685 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2686 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2687 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2688 max_path_offset = cmp::max(
2689 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2690 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2691 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2693 // Add 'shadow' CLTV offset to the final hop
2694 if let Some(tail) = path.blinded_tail.as_mut() {
2695 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2696 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2698 if let Some(last_hop) = path.hops.last_mut() {
2699 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2700 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2705 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2706 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2708 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2709 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2710 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2711 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2712 ) -> Result<Route, LightningError>
2713 where L::Target: Logger, GL::Target: Logger {
2714 let graph_lock = network_graph.read_only();
2715 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2716 &graph_lock, logger, random_seed_bytes)?;
2717 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2721 fn build_route_from_hops_internal<L: Deref>(
2722 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2723 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2724 ) -> Result<Route, LightningError> where L::Target: Logger {
2727 our_node_id: NodeId,
2728 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2731 impl ScoreLookUp for HopScorer {
2732 type ScoreParams = ();
2733 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2734 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2736 let mut cur_id = self.our_node_id;
2737 for i in 0..self.hop_ids.len() {
2738 if let Some(next_id) = self.hop_ids[i] {
2739 if cur_id == *source && next_id == *target {
2751 impl<'a> Writeable for HopScorer {
2753 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2758 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2759 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2762 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2763 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2764 for i in 0..hops.len() {
2765 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2768 let scorer = HopScorer { our_node_id, hop_ids };
2770 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
2775 use crate::blinded_path::{BlindedHop, BlindedPath};
2776 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2777 use crate::routing::utxo::UtxoResult;
2778 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2779 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2780 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2781 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2782 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2783 use crate::chain::transaction::OutPoint;
2784 use crate::sign::EntropySource;
2785 use crate::ln::ChannelId;
2786 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2787 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2788 use crate::ln::channelmanager;
2789 use crate::offers::invoice::BlindedPayInfo;
2790 use crate::util::config::UserConfig;
2791 use crate::util::test_utils as ln_test_utils;
2792 use crate::util::chacha20::ChaCha20;
2793 use crate::util::ser::{Readable, Writeable};
2795 use crate::util::ser::Writer;
2797 use bitcoin::hashes::Hash;
2798 use bitcoin::network::constants::Network;
2799 use bitcoin::blockdata::constants::genesis_block;
2800 use bitcoin::blockdata::script::Builder;
2801 use bitcoin::blockdata::opcodes;
2802 use bitcoin::blockdata::transaction::TxOut;
2806 use bitcoin::secp256k1::{PublicKey,SecretKey};
2807 use bitcoin::secp256k1::Secp256k1;
2809 use crate::io::Cursor;
2810 use crate::prelude::*;
2811 use crate::sync::Arc;
2813 use core::convert::TryInto;
2815 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2816 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2817 channelmanager::ChannelDetails {
2818 channel_id: ChannelId::new_zero(),
2819 counterparty: channelmanager::ChannelCounterparty {
2822 unspendable_punishment_reserve: 0,
2823 forwarding_info: None,
2824 outbound_htlc_minimum_msat: None,
2825 outbound_htlc_maximum_msat: None,
2827 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2830 outbound_scid_alias: None,
2831 inbound_scid_alias: None,
2832 channel_value_satoshis: 0,
2834 outbound_capacity_msat,
2835 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2836 next_outbound_htlc_minimum_msat: 0,
2837 inbound_capacity_msat: 42,
2838 unspendable_punishment_reserve: None,
2839 confirmations_required: None,
2840 confirmations: None,
2841 force_close_spend_delay: None,
2842 is_outbound: true, is_channel_ready: true,
2843 is_usable: true, is_public: true,
2844 inbound_htlc_minimum_msat: None,
2845 inbound_htlc_maximum_msat: None,
2847 feerate_sat_per_1000_weight: None,
2848 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2853 fn simple_route_test() {
2854 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2855 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2856 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2857 let scorer = ln_test_utils::TestScorer::new();
2858 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2859 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2861 // Simple route to 2 via 1
2863 let route_params = RouteParameters::from_payment_params_and_value(
2864 payment_params.clone(), 0);
2865 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2866 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
2867 &Default::default(), &random_seed_bytes) {
2868 assert_eq!(err, "Cannot send a payment of 0 msat");
2869 } else { panic!(); }
2871 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2872 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2873 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2874 assert_eq!(route.paths[0].hops.len(), 2);
2876 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2877 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2878 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2879 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2880 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2881 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2883 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2884 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2885 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2886 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2887 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2888 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2892 fn invalid_first_hop_test() {
2893 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2894 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2895 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2896 let scorer = ln_test_utils::TestScorer::new();
2897 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2898 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2900 // Simple route to 2 via 1
2902 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2904 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2905 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2906 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2907 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
2908 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2909 } else { panic!(); }
2911 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2912 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2913 assert_eq!(route.paths[0].hops.len(), 2);
2917 fn htlc_minimum_test() {
2918 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2919 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2920 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2921 let scorer = ln_test_utils::TestScorer::new();
2922 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2923 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2925 // Simple route to 2 via 1
2927 // Disable other paths
2928 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2929 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2930 short_channel_id: 12,
2932 flags: 2, // to disable
2933 cltv_expiry_delta: 0,
2934 htlc_minimum_msat: 0,
2935 htlc_maximum_msat: MAX_VALUE_MSAT,
2937 fee_proportional_millionths: 0,
2938 excess_data: Vec::new()
2940 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2941 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2942 short_channel_id: 3,
2944 flags: 2, // to disable
2945 cltv_expiry_delta: 0,
2946 htlc_minimum_msat: 0,
2947 htlc_maximum_msat: MAX_VALUE_MSAT,
2949 fee_proportional_millionths: 0,
2950 excess_data: Vec::new()
2952 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2953 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2954 short_channel_id: 13,
2956 flags: 2, // to disable
2957 cltv_expiry_delta: 0,
2958 htlc_minimum_msat: 0,
2959 htlc_maximum_msat: MAX_VALUE_MSAT,
2961 fee_proportional_millionths: 0,
2962 excess_data: Vec::new()
2964 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2965 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2966 short_channel_id: 6,
2968 flags: 2, // to disable
2969 cltv_expiry_delta: 0,
2970 htlc_minimum_msat: 0,
2971 htlc_maximum_msat: MAX_VALUE_MSAT,
2973 fee_proportional_millionths: 0,
2974 excess_data: Vec::new()
2976 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2977 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2978 short_channel_id: 7,
2980 flags: 2, // to disable
2981 cltv_expiry_delta: 0,
2982 htlc_minimum_msat: 0,
2983 htlc_maximum_msat: MAX_VALUE_MSAT,
2985 fee_proportional_millionths: 0,
2986 excess_data: Vec::new()
2989 // Check against amount_to_transfer_over_msat.
2990 // Set minimal HTLC of 200_000_000 msat.
2991 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2992 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2993 short_channel_id: 2,
2996 cltv_expiry_delta: 0,
2997 htlc_minimum_msat: 200_000_000,
2998 htlc_maximum_msat: MAX_VALUE_MSAT,
3000 fee_proportional_millionths: 0,
3001 excess_data: Vec::new()
3004 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3006 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3008 short_channel_id: 4,
3011 cltv_expiry_delta: 0,
3012 htlc_minimum_msat: 0,
3013 htlc_maximum_msat: 199_999_999,
3015 fee_proportional_millionths: 0,
3016 excess_data: Vec::new()
3019 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3020 let route_params = RouteParameters::from_payment_params_and_value(
3021 payment_params, 199_999_999);
3022 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3023 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3024 &Default::default(), &random_seed_bytes) {
3025 assert_eq!(err, "Failed to find a path to the given destination");
3026 } else { panic!(); }
3028 // Lift the restriction on the first hop.
3029 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3030 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3031 short_channel_id: 2,
3034 cltv_expiry_delta: 0,
3035 htlc_minimum_msat: 0,
3036 htlc_maximum_msat: MAX_VALUE_MSAT,
3038 fee_proportional_millionths: 0,
3039 excess_data: Vec::new()
3042 // A payment above the minimum should pass
3043 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3044 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3045 assert_eq!(route.paths[0].hops.len(), 2);
3049 fn htlc_minimum_overpay_test() {
3050 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3051 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3052 let config = UserConfig::default();
3053 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3054 let scorer = ln_test_utils::TestScorer::new();
3055 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3056 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3058 // A route to node#2 via two paths.
3059 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3060 // Thus, they can't send 60 without overpaying.
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: 35_000,
3068 htlc_maximum_msat: 40_000,
3070 fee_proportional_millionths: 0,
3071 excess_data: Vec::new()
3073 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3074 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3075 short_channel_id: 12,
3078 cltv_expiry_delta: 0,
3079 htlc_minimum_msat: 35_000,
3080 htlc_maximum_msat: 40_000,
3082 fee_proportional_millionths: 0,
3083 excess_data: Vec::new()
3087 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3088 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3089 short_channel_id: 13,
3092 cltv_expiry_delta: 0,
3093 htlc_minimum_msat: 0,
3094 htlc_maximum_msat: MAX_VALUE_MSAT,
3096 fee_proportional_millionths: 0,
3097 excess_data: Vec::new()
3099 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3100 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3101 short_channel_id: 4,
3104 cltv_expiry_delta: 0,
3105 htlc_minimum_msat: 0,
3106 htlc_maximum_msat: MAX_VALUE_MSAT,
3108 fee_proportional_millionths: 0,
3109 excess_data: Vec::new()
3112 // Disable other paths
3113 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3114 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3115 short_channel_id: 1,
3117 flags: 2, // to disable
3118 cltv_expiry_delta: 0,
3119 htlc_minimum_msat: 0,
3120 htlc_maximum_msat: MAX_VALUE_MSAT,
3122 fee_proportional_millionths: 0,
3123 excess_data: Vec::new()
3126 let mut route_params = RouteParameters::from_payment_params_and_value(
3127 payment_params.clone(), 60_000);
3128 route_params.max_total_routing_fee_msat = Some(15_000);
3129 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3130 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3131 // Overpay fees to hit htlc_minimum_msat.
3132 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3133 // TODO: this could be better balanced to overpay 10k and not 15k.
3134 assert_eq!(overpaid_fees, 15_000);
3136 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3137 // while taking even more fee to match htlc_minimum_msat.
3138 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3139 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3140 short_channel_id: 12,
3143 cltv_expiry_delta: 0,
3144 htlc_minimum_msat: 65_000,
3145 htlc_maximum_msat: 80_000,
3147 fee_proportional_millionths: 0,
3148 excess_data: Vec::new()
3150 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3151 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3152 short_channel_id: 2,
3155 cltv_expiry_delta: 0,
3156 htlc_minimum_msat: 0,
3157 htlc_maximum_msat: MAX_VALUE_MSAT,
3159 fee_proportional_millionths: 0,
3160 excess_data: Vec::new()
3162 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3163 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3164 short_channel_id: 4,
3167 cltv_expiry_delta: 0,
3168 htlc_minimum_msat: 0,
3169 htlc_maximum_msat: MAX_VALUE_MSAT,
3171 fee_proportional_millionths: 100_000,
3172 excess_data: Vec::new()
3175 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3176 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3177 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3178 assert_eq!(route.paths.len(), 1);
3179 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3180 let fees = route.paths[0].hops[0].fee_msat;
3181 assert_eq!(fees, 5_000);
3183 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3184 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3185 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3186 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3187 // the other channel.
3188 assert_eq!(route.paths.len(), 1);
3189 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3190 let fees = route.paths[0].hops[0].fee_msat;
3191 assert_eq!(fees, 5_000);
3195 fn disable_channels_test() {
3196 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3197 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3198 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3199 let scorer = ln_test_utils::TestScorer::new();
3200 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3201 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3203 // // Disable channels 4 and 12 by flags=2
3204 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3205 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3206 short_channel_id: 4,
3208 flags: 2, // to disable
3209 cltv_expiry_delta: 0,
3210 htlc_minimum_msat: 0,
3211 htlc_maximum_msat: MAX_VALUE_MSAT,
3213 fee_proportional_millionths: 0,
3214 excess_data: Vec::new()
3216 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3217 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3218 short_channel_id: 12,
3220 flags: 2, // to disable
3221 cltv_expiry_delta: 0,
3222 htlc_minimum_msat: 0,
3223 htlc_maximum_msat: MAX_VALUE_MSAT,
3225 fee_proportional_millionths: 0,
3226 excess_data: Vec::new()
3229 // If all the channels require some features we don't understand, route should fail
3230 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3231 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3232 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3233 &Default::default(), &random_seed_bytes) {
3234 assert_eq!(err, "Failed to find a path to the given destination");
3235 } else { panic!(); }
3237 // If we specify a channel to node7, that overrides our local channel view and that gets used
3238 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3239 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3240 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3241 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3242 &Default::default(), &random_seed_bytes).unwrap();
3243 assert_eq!(route.paths[0].hops.len(), 2);
3245 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3246 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3247 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3248 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3249 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3250 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3252 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3253 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3254 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3255 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3256 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3257 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3261 fn disable_node_test() {
3262 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3263 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3264 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3265 let scorer = ln_test_utils::TestScorer::new();
3266 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3267 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3269 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3270 let mut unknown_features = NodeFeatures::empty();
3271 unknown_features.set_unknown_feature_required();
3272 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3273 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3274 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3276 // If all nodes require some features we don't understand, route should fail
3277 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3278 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3279 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3280 &Default::default(), &random_seed_bytes) {
3281 assert_eq!(err, "Failed to find a path to the given destination");
3282 } else { panic!(); }
3284 // If we specify a channel to node7, that overrides our local channel view and that gets used
3285 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3286 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3287 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3288 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3289 &Default::default(), &random_seed_bytes).unwrap();
3290 assert_eq!(route.paths[0].hops.len(), 2);
3292 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3293 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3294 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3295 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3296 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3297 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3299 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3300 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3301 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3302 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3303 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3304 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3306 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3307 // naively) assume that the user checked the feature bits on the invoice, which override
3308 // the node_announcement.
3312 fn our_chans_test() {
3313 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3314 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3315 let scorer = ln_test_utils::TestScorer::new();
3316 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3317 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3319 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3320 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3321 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3322 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3323 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3324 assert_eq!(route.paths[0].hops.len(), 3);
3326 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3327 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3328 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3329 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3330 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3331 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3333 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3334 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3335 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3336 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3337 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3338 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3340 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3341 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3342 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3343 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3344 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3345 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3347 // If we specify a channel to node7, that overrides our local channel view and that gets used
3348 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3349 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3350 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3351 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3352 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3353 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3354 &Default::default(), &random_seed_bytes).unwrap();
3355 assert_eq!(route.paths[0].hops.len(), 2);
3357 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3358 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3359 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3360 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3361 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3362 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3364 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3365 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3366 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3367 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3368 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3369 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3372 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3373 let zero_fees = RoutingFees {
3375 proportional_millionths: 0,
3377 vec![RouteHint(vec![RouteHintHop {
3378 src_node_id: nodes[3],
3379 short_channel_id: 8,
3381 cltv_expiry_delta: (8 << 4) | 1,
3382 htlc_minimum_msat: None,
3383 htlc_maximum_msat: None,
3385 ]), RouteHint(vec![RouteHintHop {
3386 src_node_id: nodes[4],
3387 short_channel_id: 9,
3390 proportional_millionths: 0,
3392 cltv_expiry_delta: (9 << 4) | 1,
3393 htlc_minimum_msat: None,
3394 htlc_maximum_msat: None,
3395 }]), RouteHint(vec![RouteHintHop {
3396 src_node_id: nodes[5],
3397 short_channel_id: 10,
3399 cltv_expiry_delta: (10 << 4) | 1,
3400 htlc_minimum_msat: None,
3401 htlc_maximum_msat: None,
3405 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3406 let zero_fees = RoutingFees {
3408 proportional_millionths: 0,
3410 vec![RouteHint(vec![RouteHintHop {
3411 src_node_id: nodes[2],
3412 short_channel_id: 5,
3415 proportional_millionths: 0,
3417 cltv_expiry_delta: (5 << 4) | 1,
3418 htlc_minimum_msat: None,
3419 htlc_maximum_msat: None,
3421 src_node_id: nodes[3],
3422 short_channel_id: 8,
3424 cltv_expiry_delta: (8 << 4) | 1,
3425 htlc_minimum_msat: None,
3426 htlc_maximum_msat: None,
3428 ]), RouteHint(vec![RouteHintHop {
3429 src_node_id: nodes[4],
3430 short_channel_id: 9,
3433 proportional_millionths: 0,
3435 cltv_expiry_delta: (9 << 4) | 1,
3436 htlc_minimum_msat: None,
3437 htlc_maximum_msat: None,
3438 }]), RouteHint(vec![RouteHintHop {
3439 src_node_id: nodes[5],
3440 short_channel_id: 10,
3442 cltv_expiry_delta: (10 << 4) | 1,
3443 htlc_minimum_msat: None,
3444 htlc_maximum_msat: None,
3449 fn partial_route_hint_test() {
3450 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3451 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3452 let scorer = ln_test_utils::TestScorer::new();
3453 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3454 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3456 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3457 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3458 // RouteHint may be partially used by the algo to build the best path.
3460 // First check that last hop can't have its source as the payee.
3461 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3462 src_node_id: nodes[6],
3463 short_channel_id: 8,
3466 proportional_millionths: 0,
3468 cltv_expiry_delta: (8 << 4) | 1,
3469 htlc_minimum_msat: None,
3470 htlc_maximum_msat: None,
3473 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3474 invalid_last_hops.push(invalid_last_hop);
3476 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3477 .with_route_hints(invalid_last_hops).unwrap();
3478 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3479 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3480 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3481 &Default::default(), &random_seed_bytes) {
3482 assert_eq!(err, "Route hint cannot have the payee as the source.");
3483 } else { panic!(); }
3486 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3487 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3488 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3489 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3490 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3491 assert_eq!(route.paths[0].hops.len(), 5);
3493 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3494 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3495 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3496 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3497 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3498 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3500 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3501 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3502 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3503 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3504 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3505 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3507 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3508 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3509 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3510 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3511 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3512 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3514 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3515 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3516 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3517 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3518 // If we have a peer in the node map, we'll use their features here since we don't have
3519 // a way of figuring out their features from the invoice:
3520 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3521 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3523 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3524 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3525 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3526 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3527 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3528 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3531 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3532 let zero_fees = RoutingFees {
3534 proportional_millionths: 0,
3536 vec![RouteHint(vec![RouteHintHop {
3537 src_node_id: nodes[3],
3538 short_channel_id: 8,
3540 cltv_expiry_delta: (8 << 4) | 1,
3541 htlc_minimum_msat: None,
3542 htlc_maximum_msat: None,
3543 }]), RouteHint(vec![
3545 ]), RouteHint(vec![RouteHintHop {
3546 src_node_id: nodes[5],
3547 short_channel_id: 10,
3549 cltv_expiry_delta: (10 << 4) | 1,
3550 htlc_minimum_msat: None,
3551 htlc_maximum_msat: None,
3556 fn ignores_empty_last_hops_test() {
3557 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3558 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3559 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3560 let scorer = ln_test_utils::TestScorer::new();
3561 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3562 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3564 // Test handling of an empty RouteHint passed in Invoice.
3565 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3566 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3567 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3568 assert_eq!(route.paths[0].hops.len(), 5);
3570 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3571 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3572 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3573 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3574 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3575 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3577 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3578 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3579 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3580 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3581 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3582 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3584 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3585 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3586 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3587 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3588 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3589 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3591 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3592 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3593 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3594 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3595 // If we have a peer in the node map, we'll use their features here since we don't have
3596 // a way of figuring out their features from the invoice:
3597 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3598 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3600 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3601 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3602 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3603 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3604 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3605 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3608 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3610 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3611 let zero_fees = RoutingFees {
3613 proportional_millionths: 0,
3615 vec![RouteHint(vec![RouteHintHop {
3616 src_node_id: hint_hops[0],
3617 short_channel_id: 0xff00,
3620 proportional_millionths: 0,
3622 cltv_expiry_delta: (5 << 4) | 1,
3623 htlc_minimum_msat: None,
3624 htlc_maximum_msat: None,
3626 src_node_id: hint_hops[1],
3627 short_channel_id: 0xff01,
3629 cltv_expiry_delta: (8 << 4) | 1,
3630 htlc_minimum_msat: None,
3631 htlc_maximum_msat: None,
3636 fn multi_hint_last_hops_test() {
3637 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3638 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3639 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3640 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3641 let scorer = ln_test_utils::TestScorer::new();
3642 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3643 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3644 // Test through channels 2, 3, 0xff00, 0xff01.
3645 // Test shows that multiple hop hints are considered.
3647 // Disabling channels 6 & 7 by flags=2
3648 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3649 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3650 short_channel_id: 6,
3652 flags: 2, // to disable
3653 cltv_expiry_delta: 0,
3654 htlc_minimum_msat: 0,
3655 htlc_maximum_msat: MAX_VALUE_MSAT,
3657 fee_proportional_millionths: 0,
3658 excess_data: Vec::new()
3660 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3661 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3662 short_channel_id: 7,
3664 flags: 2, // to disable
3665 cltv_expiry_delta: 0,
3666 htlc_minimum_msat: 0,
3667 htlc_maximum_msat: MAX_VALUE_MSAT,
3669 fee_proportional_millionths: 0,
3670 excess_data: Vec::new()
3673 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3674 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3675 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3676 assert_eq!(route.paths[0].hops.len(), 4);
3678 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3679 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3680 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3681 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3682 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3683 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3685 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3686 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3687 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3688 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3689 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3690 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3692 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3693 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3694 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3695 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3696 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3697 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3699 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3700 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3701 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3702 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3703 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3704 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3708 fn private_multi_hint_last_hops_test() {
3709 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3710 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3712 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3713 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3715 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3716 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3717 let scorer = ln_test_utils::TestScorer::new();
3718 // Test through channels 2, 3, 0xff00, 0xff01.
3719 // Test shows that multiple hop hints are considered.
3721 // Disabling channels 6 & 7 by flags=2
3722 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3723 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3724 short_channel_id: 6,
3726 flags: 2, // to disable
3727 cltv_expiry_delta: 0,
3728 htlc_minimum_msat: 0,
3729 htlc_maximum_msat: MAX_VALUE_MSAT,
3731 fee_proportional_millionths: 0,
3732 excess_data: Vec::new()
3734 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3735 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3736 short_channel_id: 7,
3738 flags: 2, // to disable
3739 cltv_expiry_delta: 0,
3740 htlc_minimum_msat: 0,
3741 htlc_maximum_msat: MAX_VALUE_MSAT,
3743 fee_proportional_millionths: 0,
3744 excess_data: Vec::new()
3747 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3748 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3749 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
3750 assert_eq!(route.paths[0].hops.len(), 4);
3752 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3753 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3754 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3755 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3756 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3757 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3759 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3760 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3761 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3762 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3763 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3764 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3766 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3767 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3768 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3769 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3770 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3771 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3773 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3774 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3775 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3776 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3777 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3778 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3781 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3782 let zero_fees = RoutingFees {
3784 proportional_millionths: 0,
3786 vec![RouteHint(vec![RouteHintHop {
3787 src_node_id: nodes[4],
3788 short_channel_id: 11,
3790 cltv_expiry_delta: (11 << 4) | 1,
3791 htlc_minimum_msat: None,
3792 htlc_maximum_msat: None,
3794 src_node_id: nodes[3],
3795 short_channel_id: 8,
3797 cltv_expiry_delta: (8 << 4) | 1,
3798 htlc_minimum_msat: None,
3799 htlc_maximum_msat: None,
3800 }]), RouteHint(vec![RouteHintHop {
3801 src_node_id: nodes[4],
3802 short_channel_id: 9,
3805 proportional_millionths: 0,
3807 cltv_expiry_delta: (9 << 4) | 1,
3808 htlc_minimum_msat: None,
3809 htlc_maximum_msat: None,
3810 }]), RouteHint(vec![RouteHintHop {
3811 src_node_id: nodes[5],
3812 short_channel_id: 10,
3814 cltv_expiry_delta: (10 << 4) | 1,
3815 htlc_minimum_msat: None,
3816 htlc_maximum_msat: None,
3821 fn last_hops_with_public_channel_test() {
3822 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3823 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3824 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3825 let scorer = ln_test_utils::TestScorer::new();
3826 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3827 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3828 // This test shows that public routes can be present in the invoice
3829 // which would be handled in the same manner.
3831 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3832 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3833 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3834 assert_eq!(route.paths[0].hops.len(), 5);
3836 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3837 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3838 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3839 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3840 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3841 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3843 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3844 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3845 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3846 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3847 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3848 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3850 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3851 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3852 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3853 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3854 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3855 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3857 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3858 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3859 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3860 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3861 // If we have a peer in the node map, we'll use their features here since we don't have
3862 // a way of figuring out their features from the invoice:
3863 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3864 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3866 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3867 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3868 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3869 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3870 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3871 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3875 fn our_chans_last_hop_connect_test() {
3876 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3877 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3878 let scorer = ln_test_utils::TestScorer::new();
3879 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3880 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3882 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3883 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3884 let mut last_hops = last_hops(&nodes);
3885 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3886 .with_route_hints(last_hops.clone()).unwrap();
3887 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3888 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3889 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3890 &Default::default(), &random_seed_bytes).unwrap();
3891 assert_eq!(route.paths[0].hops.len(), 2);
3893 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3894 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3895 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3896 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3897 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3898 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3900 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
3901 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
3902 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3903 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3904 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3905 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3907 last_hops[0].0[0].fees.base_msat = 1000;
3909 // Revert to via 6 as the fee on 8 goes up
3910 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3911 .with_route_hints(last_hops).unwrap();
3912 let route_params = RouteParameters::from_payment_params_and_value(
3913 payment_params.clone(), 100);
3914 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3915 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3916 assert_eq!(route.paths[0].hops.len(), 4);
3918 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3919 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3920 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
3921 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3922 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3923 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3925 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3926 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3927 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3928 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
3929 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3930 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3932 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
3933 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
3934 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3935 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
3936 // If we have a peer in the node map, we'll use their features here since we don't have
3937 // a way of figuring out their features from the invoice:
3938 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
3939 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
3941 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3942 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
3943 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3944 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3945 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3946 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3948 // ...but still use 8 for larger payments as 6 has a variable feerate
3949 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
3950 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3951 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3952 assert_eq!(route.paths[0].hops.len(), 5);
3954 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3955 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3956 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
3957 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3958 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3959 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3961 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3962 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3963 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3964 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3965 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3966 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3968 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3969 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3970 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3971 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3972 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3973 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3975 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3976 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3977 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
3978 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3979 // If we have a peer in the node map, we'll use their features here since we don't have
3980 // a way of figuring out their features from the invoice:
3981 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3982 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3984 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3985 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3986 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
3987 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3988 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3989 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3992 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> {
3993 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3994 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3995 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3997 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3998 let last_hops = RouteHint(vec![RouteHintHop {
3999 src_node_id: middle_node_id,
4000 short_channel_id: 8,
4003 proportional_millionths: last_hop_fee_prop,
4005 cltv_expiry_delta: (8 << 4) | 1,
4006 htlc_minimum_msat: None,
4007 htlc_maximum_msat: last_hop_htlc_max,
4009 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4010 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4011 let scorer = ln_test_utils::TestScorer::new();
4012 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4013 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4014 let logger = ln_test_utils::TestLogger::new();
4015 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4016 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4017 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4018 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4019 &random_seed_bytes);
4024 fn unannounced_path_test() {
4025 // We should be able to send a payment to a destination without any help of a routing graph
4026 // if we have a channel with a common counterparty that appears in the first and last hop
4028 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4030 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4031 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4032 assert_eq!(route.paths[0].hops.len(), 2);
4034 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4035 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4036 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4037 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4038 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4039 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4041 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4042 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4043 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4044 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4045 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4046 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4050 fn overflow_unannounced_path_test_liquidity_underflow() {
4051 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4052 // the last-hop had a fee which overflowed a u64, we'd panic.
4053 // This was due to us adding the first-hop from us unconditionally, causing us to think
4054 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4055 // In this test, we previously hit a subtraction underflow due to having less available
4056 // liquidity at the last hop than 0.
4057 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());
4061 fn overflow_unannounced_path_test_feerate_overflow() {
4062 // This tests for the same case as above, except instead of hitting a subtraction
4063 // underflow, we hit a case where the fee charged at a hop overflowed.
4064 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());
4068 fn available_amount_while_routing_test() {
4069 // Tests whether we choose the correct available channel amount while routing.
4071 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4072 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4073 let scorer = ln_test_utils::TestScorer::new();
4074 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4075 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4076 let config = UserConfig::default();
4077 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4079 // We will use a simple single-path route from
4080 // our node to node2 via node0: channels {1, 3}.
4082 // First disable all other paths.
4083 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4084 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4085 short_channel_id: 2,
4088 cltv_expiry_delta: 0,
4089 htlc_minimum_msat: 0,
4090 htlc_maximum_msat: 100_000,
4092 fee_proportional_millionths: 0,
4093 excess_data: Vec::new()
4095 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4096 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4097 short_channel_id: 12,
4100 cltv_expiry_delta: 0,
4101 htlc_minimum_msat: 0,
4102 htlc_maximum_msat: 100_000,
4104 fee_proportional_millionths: 0,
4105 excess_data: Vec::new()
4108 // Make the first channel (#1) very permissive,
4109 // and we will be testing all limits on the second channel.
4110 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4111 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4112 short_channel_id: 1,
4115 cltv_expiry_delta: 0,
4116 htlc_minimum_msat: 0,
4117 htlc_maximum_msat: 1_000_000_000,
4119 fee_proportional_millionths: 0,
4120 excess_data: Vec::new()
4123 // First, let's see if routing works if we have absolutely no idea about the available amount.
4124 // In this case, it should be set to 250_000 sats.
4125 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4126 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4127 short_channel_id: 3,
4130 cltv_expiry_delta: 0,
4131 htlc_minimum_msat: 0,
4132 htlc_maximum_msat: 250_000_000,
4134 fee_proportional_millionths: 0,
4135 excess_data: Vec::new()
4139 // Attempt to route more than available results in a failure.
4140 let route_params = RouteParameters::from_payment_params_and_value(
4141 payment_params.clone(), 250_000_001);
4142 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4143 &our_id, &route_params, &network_graph.read_only(), None,
4144 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4145 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4146 } else { panic!(); }
4150 // Now, attempt to route an exact amount we have should be fine.
4151 let route_params = RouteParameters::from_payment_params_and_value(
4152 payment_params.clone(), 250_000_000);
4153 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4154 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4155 assert_eq!(route.paths.len(), 1);
4156 let path = route.paths.last().unwrap();
4157 assert_eq!(path.hops.len(), 2);
4158 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4159 assert_eq!(path.final_value_msat(), 250_000_000);
4162 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4163 // Disable channel #1 and use another first hop.
4164 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4165 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4166 short_channel_id: 1,
4169 cltv_expiry_delta: 0,
4170 htlc_minimum_msat: 0,
4171 htlc_maximum_msat: 1_000_000_000,
4173 fee_proportional_millionths: 0,
4174 excess_data: Vec::new()
4177 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4178 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4181 // Attempt to route more than available results in a failure.
4182 let route_params = RouteParameters::from_payment_params_and_value(
4183 payment_params.clone(), 200_000_001);
4184 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4185 &our_id, &route_params, &network_graph.read_only(),
4186 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4187 &Default::default(), &random_seed_bytes) {
4188 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4189 } else { panic!(); }
4193 // Now, attempt to route an exact amount we have should be fine.
4194 let route_params = RouteParameters::from_payment_params_and_value(
4195 payment_params.clone(), 200_000_000);
4196 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4197 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4198 &Default::default(), &random_seed_bytes).unwrap();
4199 assert_eq!(route.paths.len(), 1);
4200 let path = route.paths.last().unwrap();
4201 assert_eq!(path.hops.len(), 2);
4202 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4203 assert_eq!(path.final_value_msat(), 200_000_000);
4206 // Enable channel #1 back.
4207 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4208 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4209 short_channel_id: 1,
4212 cltv_expiry_delta: 0,
4213 htlc_minimum_msat: 0,
4214 htlc_maximum_msat: 1_000_000_000,
4216 fee_proportional_millionths: 0,
4217 excess_data: Vec::new()
4221 // Now let's see if routing works if we know only htlc_maximum_msat.
4222 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4223 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4224 short_channel_id: 3,
4227 cltv_expiry_delta: 0,
4228 htlc_minimum_msat: 0,
4229 htlc_maximum_msat: 15_000,
4231 fee_proportional_millionths: 0,
4232 excess_data: Vec::new()
4236 // Attempt to route more than available results in a failure.
4237 let route_params = RouteParameters::from_payment_params_and_value(
4238 payment_params.clone(), 15_001);
4239 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4240 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4241 &scorer, &Default::default(), &random_seed_bytes) {
4242 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4243 } else { panic!(); }
4247 // Now, attempt to route an exact amount we have should be fine.
4248 let route_params = RouteParameters::from_payment_params_and_value(
4249 payment_params.clone(), 15_000);
4250 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4251 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4252 assert_eq!(route.paths.len(), 1);
4253 let path = route.paths.last().unwrap();
4254 assert_eq!(path.hops.len(), 2);
4255 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4256 assert_eq!(path.final_value_msat(), 15_000);
4259 // Now let's see if routing works if we know only capacity from the UTXO.
4261 // We can't change UTXO capacity on the fly, so we'll disable
4262 // the existing channel and add another one with the capacity we need.
4263 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4265 short_channel_id: 3,
4268 cltv_expiry_delta: 0,
4269 htlc_minimum_msat: 0,
4270 htlc_maximum_msat: MAX_VALUE_MSAT,
4272 fee_proportional_millionths: 0,
4273 excess_data: Vec::new()
4276 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4277 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4278 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4279 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4280 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4282 *chain_monitor.utxo_ret.lock().unwrap() =
4283 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4284 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4286 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4287 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4288 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4289 short_channel_id: 333,
4292 cltv_expiry_delta: (3 << 4) | 1,
4293 htlc_minimum_msat: 0,
4294 htlc_maximum_msat: 15_000,
4296 fee_proportional_millionths: 0,
4297 excess_data: Vec::new()
4299 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4300 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4301 short_channel_id: 333,
4304 cltv_expiry_delta: (3 << 4) | 2,
4305 htlc_minimum_msat: 0,
4306 htlc_maximum_msat: 15_000,
4308 fee_proportional_millionths: 0,
4309 excess_data: Vec::new()
4313 // Attempt to route more than available results in a failure.
4314 let route_params = RouteParameters::from_payment_params_and_value(
4315 payment_params.clone(), 15_001);
4316 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4317 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4318 &scorer, &Default::default(), &random_seed_bytes) {
4319 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4320 } else { panic!(); }
4324 // Now, attempt to route an exact amount we have should be fine.
4325 let route_params = RouteParameters::from_payment_params_and_value(
4326 payment_params.clone(), 15_000);
4327 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4328 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4329 assert_eq!(route.paths.len(), 1);
4330 let path = route.paths.last().unwrap();
4331 assert_eq!(path.hops.len(), 2);
4332 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4333 assert_eq!(path.final_value_msat(), 15_000);
4336 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4337 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4338 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4339 short_channel_id: 333,
4342 cltv_expiry_delta: 0,
4343 htlc_minimum_msat: 0,
4344 htlc_maximum_msat: 10_000,
4346 fee_proportional_millionths: 0,
4347 excess_data: Vec::new()
4351 // Attempt to route more than available results in a failure.
4352 let route_params = RouteParameters::from_payment_params_and_value(
4353 payment_params.clone(), 10_001);
4354 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4355 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4356 &scorer, &Default::default(), &random_seed_bytes) {
4357 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4358 } else { panic!(); }
4362 // Now, attempt to route an exact amount we have should be fine.
4363 let route_params = RouteParameters::from_payment_params_and_value(
4364 payment_params.clone(), 10_000);
4365 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4366 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4367 assert_eq!(route.paths.len(), 1);
4368 let path = route.paths.last().unwrap();
4369 assert_eq!(path.hops.len(), 2);
4370 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4371 assert_eq!(path.final_value_msat(), 10_000);
4376 fn available_liquidity_last_hop_test() {
4377 // Check that available liquidity properly limits the path even when only
4378 // one of the latter hops is limited.
4379 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4380 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4381 let scorer = ln_test_utils::TestScorer::new();
4382 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4383 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4384 let config = UserConfig::default();
4385 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4387 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4388 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4389 // Total capacity: 50 sats.
4391 // Disable other potential paths.
4392 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4393 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4394 short_channel_id: 2,
4397 cltv_expiry_delta: 0,
4398 htlc_minimum_msat: 0,
4399 htlc_maximum_msat: 100_000,
4401 fee_proportional_millionths: 0,
4402 excess_data: Vec::new()
4404 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4405 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4406 short_channel_id: 7,
4409 cltv_expiry_delta: 0,
4410 htlc_minimum_msat: 0,
4411 htlc_maximum_msat: 100_000,
4413 fee_proportional_millionths: 0,
4414 excess_data: Vec::new()
4419 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4420 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4421 short_channel_id: 12,
4424 cltv_expiry_delta: 0,
4425 htlc_minimum_msat: 0,
4426 htlc_maximum_msat: 100_000,
4428 fee_proportional_millionths: 0,
4429 excess_data: Vec::new()
4431 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4432 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4433 short_channel_id: 13,
4436 cltv_expiry_delta: 0,
4437 htlc_minimum_msat: 0,
4438 htlc_maximum_msat: 100_000,
4440 fee_proportional_millionths: 0,
4441 excess_data: Vec::new()
4444 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4445 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4446 short_channel_id: 6,
4449 cltv_expiry_delta: 0,
4450 htlc_minimum_msat: 0,
4451 htlc_maximum_msat: 50_000,
4453 fee_proportional_millionths: 0,
4454 excess_data: Vec::new()
4456 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4457 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4458 short_channel_id: 11,
4461 cltv_expiry_delta: 0,
4462 htlc_minimum_msat: 0,
4463 htlc_maximum_msat: 100_000,
4465 fee_proportional_millionths: 0,
4466 excess_data: Vec::new()
4469 // Attempt to route more than available results in a failure.
4470 let route_params = RouteParameters::from_payment_params_and_value(
4471 payment_params.clone(), 60_000);
4472 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4473 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4474 &scorer, &Default::default(), &random_seed_bytes) {
4475 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4476 } else { panic!(); }
4480 // Now, attempt to route 49 sats (just a bit below the capacity).
4481 let route_params = RouteParameters::from_payment_params_and_value(
4482 payment_params.clone(), 49_000);
4483 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4484 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4485 assert_eq!(route.paths.len(), 1);
4486 let mut total_amount_paid_msat = 0;
4487 for path in &route.paths {
4488 assert_eq!(path.hops.len(), 4);
4489 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4490 total_amount_paid_msat += path.final_value_msat();
4492 assert_eq!(total_amount_paid_msat, 49_000);
4496 // Attempt to route an exact amount is also fine
4497 let route_params = RouteParameters::from_payment_params_and_value(
4498 payment_params, 50_000);
4499 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4500 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4501 assert_eq!(route.paths.len(), 1);
4502 let mut total_amount_paid_msat = 0;
4503 for path in &route.paths {
4504 assert_eq!(path.hops.len(), 4);
4505 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4506 total_amount_paid_msat += path.final_value_msat();
4508 assert_eq!(total_amount_paid_msat, 50_000);
4513 fn ignore_fee_first_hop_test() {
4514 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4515 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4516 let scorer = ln_test_utils::TestScorer::new();
4517 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4518 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4519 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4521 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4522 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4523 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4524 short_channel_id: 1,
4527 cltv_expiry_delta: 0,
4528 htlc_minimum_msat: 0,
4529 htlc_maximum_msat: 100_000,
4530 fee_base_msat: 1_000_000,
4531 fee_proportional_millionths: 0,
4532 excess_data: Vec::new()
4534 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4535 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4536 short_channel_id: 3,
4539 cltv_expiry_delta: 0,
4540 htlc_minimum_msat: 0,
4541 htlc_maximum_msat: 50_000,
4543 fee_proportional_millionths: 0,
4544 excess_data: Vec::new()
4548 let route_params = RouteParameters::from_payment_params_and_value(
4549 payment_params, 50_000);
4550 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4551 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4552 assert_eq!(route.paths.len(), 1);
4553 let mut total_amount_paid_msat = 0;
4554 for path in &route.paths {
4555 assert_eq!(path.hops.len(), 2);
4556 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4557 total_amount_paid_msat += path.final_value_msat();
4559 assert_eq!(total_amount_paid_msat, 50_000);
4564 fn simple_mpp_route_test() {
4565 let (secp_ctx, _, _, _, _) = build_graph();
4566 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4567 let config = UserConfig::default();
4568 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4569 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4570 do_simple_mpp_route_test(clear_payment_params);
4572 // MPP to a 1-hop blinded path for nodes[2]
4573 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4574 let blinded_path = BlindedPath {
4575 introduction_node_id: nodes[2],
4576 blinding_point: ln_test_utils::pubkey(42),
4577 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4579 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4581 fee_proportional_millionths: 0,
4582 htlc_minimum_msat: 0,
4583 htlc_maximum_msat: 0,
4584 cltv_expiry_delta: 0,
4585 features: BlindedHopFeatures::empty(),
4587 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4588 .with_bolt12_features(bolt12_features.clone()).unwrap();
4589 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4591 // MPP to 3 2-hop blinded paths
4592 let mut blinded_path_node_0 = blinded_path.clone();
4593 blinded_path_node_0.introduction_node_id = nodes[0];
4594 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4595 let mut node_0_payinfo = blinded_payinfo.clone();
4596 node_0_payinfo.htlc_maximum_msat = 50_000;
4598 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4599 blinded_path_node_7.introduction_node_id = nodes[7];
4600 let mut node_7_payinfo = blinded_payinfo.clone();
4601 node_7_payinfo.htlc_maximum_msat = 60_000;
4603 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4604 blinded_path_node_1.introduction_node_id = nodes[1];
4605 let mut node_1_payinfo = blinded_payinfo.clone();
4606 node_1_payinfo.htlc_maximum_msat = 180_000;
4608 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4610 (node_0_payinfo, blinded_path_node_0),
4611 (node_7_payinfo, blinded_path_node_7),
4612 (node_1_payinfo, blinded_path_node_1)
4614 .with_bolt12_features(bolt12_features).unwrap();
4615 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4619 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4620 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4621 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4622 let scorer = ln_test_utils::TestScorer::new();
4623 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4624 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4626 // We need a route consisting of 3 paths:
4627 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4628 // To achieve this, the amount being transferred should be around
4629 // the total capacity of these 3 paths.
4631 // First, we set limits on these (previously unlimited) channels.
4632 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4634 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4635 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4636 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4637 short_channel_id: 1,
4640 cltv_expiry_delta: 0,
4641 htlc_minimum_msat: 0,
4642 htlc_maximum_msat: 100_000,
4644 fee_proportional_millionths: 0,
4645 excess_data: Vec::new()
4647 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4648 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4649 short_channel_id: 3,
4652 cltv_expiry_delta: 0,
4653 htlc_minimum_msat: 0,
4654 htlc_maximum_msat: 50_000,
4656 fee_proportional_millionths: 0,
4657 excess_data: Vec::new()
4660 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4661 // (total limit 60).
4662 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4663 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4664 short_channel_id: 12,
4667 cltv_expiry_delta: 0,
4668 htlc_minimum_msat: 0,
4669 htlc_maximum_msat: 60_000,
4671 fee_proportional_millionths: 0,
4672 excess_data: Vec::new()
4674 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4675 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4676 short_channel_id: 13,
4679 cltv_expiry_delta: 0,
4680 htlc_minimum_msat: 0,
4681 htlc_maximum_msat: 60_000,
4683 fee_proportional_millionths: 0,
4684 excess_data: Vec::new()
4687 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4688 // (total capacity 180 sats).
4689 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4690 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4691 short_channel_id: 2,
4694 cltv_expiry_delta: 0,
4695 htlc_minimum_msat: 0,
4696 htlc_maximum_msat: 200_000,
4698 fee_proportional_millionths: 0,
4699 excess_data: Vec::new()
4701 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4702 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4703 short_channel_id: 4,
4706 cltv_expiry_delta: 0,
4707 htlc_minimum_msat: 0,
4708 htlc_maximum_msat: 180_000,
4710 fee_proportional_millionths: 0,
4711 excess_data: Vec::new()
4715 // Attempt to route more than available results in a failure.
4716 let route_params = RouteParameters::from_payment_params_and_value(
4717 payment_params.clone(), 300_000);
4718 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4719 &our_id, &route_params, &network_graph.read_only(), None,
4720 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4721 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4722 } else { panic!(); }
4726 // Attempt to route while setting max_path_count to 0 results in a failure.
4727 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4728 let route_params = RouteParameters::from_payment_params_and_value(
4729 zero_payment_params, 100);
4730 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4731 &our_id, &route_params, &network_graph.read_only(), None,
4732 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4733 assert_eq!(err, "Can't find a route with no paths allowed.");
4734 } else { panic!(); }
4738 // Attempt to route while setting max_path_count to 3 results in a failure.
4739 // This is the case because the minimal_value_contribution_msat would require each path
4740 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4741 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4742 let route_params = RouteParameters::from_payment_params_and_value(
4743 fail_payment_params, 250_000);
4744 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4745 &our_id, &route_params, &network_graph.read_only(), None,
4746 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4747 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4748 } else { panic!(); }
4752 // Now, attempt to route 250 sats (just a bit below the capacity).
4753 // Our algorithm should provide us with these 3 paths.
4754 let route_params = RouteParameters::from_payment_params_and_value(
4755 payment_params.clone(), 250_000);
4756 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4757 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4758 assert_eq!(route.paths.len(), 3);
4759 let mut total_amount_paid_msat = 0;
4760 for path in &route.paths {
4761 if let Some(bt) = &path.blinded_tail {
4762 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4764 assert_eq!(path.hops.len(), 2);
4765 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4767 total_amount_paid_msat += path.final_value_msat();
4769 assert_eq!(total_amount_paid_msat, 250_000);
4773 // Attempt to route an exact amount is also fine
4774 let route_params = RouteParameters::from_payment_params_and_value(
4775 payment_params.clone(), 290_000);
4776 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4777 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4778 assert_eq!(route.paths.len(), 3);
4779 let mut total_amount_paid_msat = 0;
4780 for path in &route.paths {
4781 if payment_params.payee.blinded_route_hints().len() != 0 {
4782 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4783 if let Some(bt) = &path.blinded_tail {
4784 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4785 if bt.hops.len() > 1 {
4786 assert_eq!(path.hops.last().unwrap().pubkey,
4787 payment_params.payee.blinded_route_hints().iter()
4788 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4789 .map(|(_, p)| p.introduction_node_id).unwrap());
4791 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4794 assert_eq!(path.hops.len(), 2);
4795 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4797 total_amount_paid_msat += path.final_value_msat();
4799 assert_eq!(total_amount_paid_msat, 290_000);
4804 fn long_mpp_route_test() {
4805 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4806 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4807 let scorer = ln_test_utils::TestScorer::new();
4808 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4809 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4810 let config = UserConfig::default();
4811 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4812 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4814 // We need a route consisting of 3 paths:
4815 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4816 // Note that these paths overlap (channels 5, 12, 13).
4817 // We will route 300 sats.
4818 // Each path will have 100 sats capacity, those channels which
4819 // are used twice will have 200 sats capacity.
4821 // Disable other potential paths.
4822 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4824 short_channel_id: 2,
4827 cltv_expiry_delta: 0,
4828 htlc_minimum_msat: 0,
4829 htlc_maximum_msat: 100_000,
4831 fee_proportional_millionths: 0,
4832 excess_data: Vec::new()
4834 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4836 short_channel_id: 7,
4839 cltv_expiry_delta: 0,
4840 htlc_minimum_msat: 0,
4841 htlc_maximum_msat: 100_000,
4843 fee_proportional_millionths: 0,
4844 excess_data: Vec::new()
4847 // Path via {node0, node2} is channels {1, 3, 5}.
4848 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4849 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4850 short_channel_id: 1,
4853 cltv_expiry_delta: 0,
4854 htlc_minimum_msat: 0,
4855 htlc_maximum_msat: 100_000,
4857 fee_proportional_millionths: 0,
4858 excess_data: Vec::new()
4860 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4861 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4862 short_channel_id: 3,
4865 cltv_expiry_delta: 0,
4866 htlc_minimum_msat: 0,
4867 htlc_maximum_msat: 100_000,
4869 fee_proportional_millionths: 0,
4870 excess_data: Vec::new()
4873 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4874 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4875 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4876 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4877 short_channel_id: 5,
4880 cltv_expiry_delta: 0,
4881 htlc_minimum_msat: 0,
4882 htlc_maximum_msat: 200_000,
4884 fee_proportional_millionths: 0,
4885 excess_data: Vec::new()
4888 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4889 // Add 100 sats to the capacities of {12, 13}, because these channels
4890 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4891 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4892 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4893 short_channel_id: 12,
4896 cltv_expiry_delta: 0,
4897 htlc_minimum_msat: 0,
4898 htlc_maximum_msat: 200_000,
4900 fee_proportional_millionths: 0,
4901 excess_data: Vec::new()
4903 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4904 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4905 short_channel_id: 13,
4908 cltv_expiry_delta: 0,
4909 htlc_minimum_msat: 0,
4910 htlc_maximum_msat: 200_000,
4912 fee_proportional_millionths: 0,
4913 excess_data: Vec::new()
4916 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4917 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4918 short_channel_id: 6,
4921 cltv_expiry_delta: 0,
4922 htlc_minimum_msat: 0,
4923 htlc_maximum_msat: 100_000,
4925 fee_proportional_millionths: 0,
4926 excess_data: Vec::new()
4928 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4929 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4930 short_channel_id: 11,
4933 cltv_expiry_delta: 0,
4934 htlc_minimum_msat: 0,
4935 htlc_maximum_msat: 100_000,
4937 fee_proportional_millionths: 0,
4938 excess_data: Vec::new()
4941 // Path via {node7, node2} is channels {12, 13, 5}.
4942 // We already limited them to 200 sats (they are used twice for 100 sats).
4943 // Nothing to do here.
4946 // Attempt to route more than available results in a failure.
4947 let route_params = RouteParameters::from_payment_params_and_value(
4948 payment_params.clone(), 350_000);
4949 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4950 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4951 &scorer, &Default::default(), &random_seed_bytes) {
4952 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4953 } else { panic!(); }
4957 // Now, attempt to route 300 sats (exact amount we can route).
4958 // Our algorithm should provide us with these 3 paths, 100 sats each.
4959 let route_params = RouteParameters::from_payment_params_and_value(
4960 payment_params, 300_000);
4961 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4962 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4963 assert_eq!(route.paths.len(), 3);
4965 let mut total_amount_paid_msat = 0;
4966 for path in &route.paths {
4967 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4968 total_amount_paid_msat += path.final_value_msat();
4970 assert_eq!(total_amount_paid_msat, 300_000);
4976 fn mpp_cheaper_route_test() {
4977 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4978 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4979 let scorer = ln_test_utils::TestScorer::new();
4980 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4981 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4982 let config = UserConfig::default();
4983 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4985 // This test checks that if we have two cheaper paths and one more expensive path,
4986 // so that liquidity-wise any 2 of 3 combination is sufficient,
4987 // two cheaper paths will be taken.
4988 // These paths have equal available liquidity.
4990 // We need a combination of 3 paths:
4991 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4992 // Note that these paths overlap (channels 5, 12, 13).
4993 // Each path will have 100 sats capacity, those channels which
4994 // are used twice will have 200 sats capacity.
4996 // Disable other potential paths.
4997 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4998 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4999 short_channel_id: 2,
5002 cltv_expiry_delta: 0,
5003 htlc_minimum_msat: 0,
5004 htlc_maximum_msat: 100_000,
5006 fee_proportional_millionths: 0,
5007 excess_data: Vec::new()
5009 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5010 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5011 short_channel_id: 7,
5014 cltv_expiry_delta: 0,
5015 htlc_minimum_msat: 0,
5016 htlc_maximum_msat: 100_000,
5018 fee_proportional_millionths: 0,
5019 excess_data: Vec::new()
5022 // Path via {node0, node2} is channels {1, 3, 5}.
5023 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5024 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5025 short_channel_id: 1,
5028 cltv_expiry_delta: 0,
5029 htlc_minimum_msat: 0,
5030 htlc_maximum_msat: 100_000,
5032 fee_proportional_millionths: 0,
5033 excess_data: Vec::new()
5035 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5036 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5037 short_channel_id: 3,
5040 cltv_expiry_delta: 0,
5041 htlc_minimum_msat: 0,
5042 htlc_maximum_msat: 100_000,
5044 fee_proportional_millionths: 0,
5045 excess_data: Vec::new()
5048 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5049 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5050 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5051 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5052 short_channel_id: 5,
5055 cltv_expiry_delta: 0,
5056 htlc_minimum_msat: 0,
5057 htlc_maximum_msat: 200_000,
5059 fee_proportional_millionths: 0,
5060 excess_data: Vec::new()
5063 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5064 // Add 100 sats to the capacities of {12, 13}, because these channels
5065 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5066 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5067 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5068 short_channel_id: 12,
5071 cltv_expiry_delta: 0,
5072 htlc_minimum_msat: 0,
5073 htlc_maximum_msat: 200_000,
5075 fee_proportional_millionths: 0,
5076 excess_data: Vec::new()
5078 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5079 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5080 short_channel_id: 13,
5083 cltv_expiry_delta: 0,
5084 htlc_minimum_msat: 0,
5085 htlc_maximum_msat: 200_000,
5087 fee_proportional_millionths: 0,
5088 excess_data: Vec::new()
5091 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5092 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5093 short_channel_id: 6,
5096 cltv_expiry_delta: 0,
5097 htlc_minimum_msat: 0,
5098 htlc_maximum_msat: 100_000,
5099 fee_base_msat: 1_000,
5100 fee_proportional_millionths: 0,
5101 excess_data: Vec::new()
5103 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5104 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5105 short_channel_id: 11,
5108 cltv_expiry_delta: 0,
5109 htlc_minimum_msat: 0,
5110 htlc_maximum_msat: 100_000,
5112 fee_proportional_millionths: 0,
5113 excess_data: Vec::new()
5116 // Path via {node7, node2} is channels {12, 13, 5}.
5117 // We already limited them to 200 sats (they are used twice for 100 sats).
5118 // Nothing to do here.
5121 // Now, attempt to route 180 sats.
5122 // Our algorithm should provide us with these 2 paths.
5123 let route_params = RouteParameters::from_payment_params_and_value(
5124 payment_params, 180_000);
5125 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5126 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5127 assert_eq!(route.paths.len(), 2);
5129 let mut total_value_transferred_msat = 0;
5130 let mut total_paid_msat = 0;
5131 for path in &route.paths {
5132 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5133 total_value_transferred_msat += path.final_value_msat();
5134 for hop in &path.hops {
5135 total_paid_msat += hop.fee_msat;
5138 // If we paid fee, this would be higher.
5139 assert_eq!(total_value_transferred_msat, 180_000);
5140 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5141 assert_eq!(total_fees_paid, 0);
5146 fn fees_on_mpp_route_test() {
5147 // This test makes sure that MPP algorithm properly takes into account
5148 // fees charged on the channels, by making the fees impactful:
5149 // if the fee is not properly accounted for, the behavior is different.
5150 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5151 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5152 let scorer = ln_test_utils::TestScorer::new();
5153 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5154 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5155 let config = UserConfig::default();
5156 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5158 // We need a route consisting of 2 paths:
5159 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5160 // We will route 200 sats, Each path will have 100 sats capacity.
5162 // This test is not particularly stable: e.g.,
5163 // there's a way to route via {node0, node2, node4}.
5164 // It works while pathfinding is deterministic, but can be broken otherwise.
5165 // It's fine to ignore this concern for now.
5167 // Disable other potential paths.
5168 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5169 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5170 short_channel_id: 2,
5173 cltv_expiry_delta: 0,
5174 htlc_minimum_msat: 0,
5175 htlc_maximum_msat: 100_000,
5177 fee_proportional_millionths: 0,
5178 excess_data: Vec::new()
5181 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5182 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5183 short_channel_id: 7,
5186 cltv_expiry_delta: 0,
5187 htlc_minimum_msat: 0,
5188 htlc_maximum_msat: 100_000,
5190 fee_proportional_millionths: 0,
5191 excess_data: Vec::new()
5194 // Path via {node0, node2} is channels {1, 3, 5}.
5195 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5196 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5197 short_channel_id: 1,
5200 cltv_expiry_delta: 0,
5201 htlc_minimum_msat: 0,
5202 htlc_maximum_msat: 100_000,
5204 fee_proportional_millionths: 0,
5205 excess_data: Vec::new()
5207 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5208 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5209 short_channel_id: 3,
5212 cltv_expiry_delta: 0,
5213 htlc_minimum_msat: 0,
5214 htlc_maximum_msat: 100_000,
5216 fee_proportional_millionths: 0,
5217 excess_data: Vec::new()
5220 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5221 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5222 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5223 short_channel_id: 5,
5226 cltv_expiry_delta: 0,
5227 htlc_minimum_msat: 0,
5228 htlc_maximum_msat: 100_000,
5230 fee_proportional_millionths: 0,
5231 excess_data: Vec::new()
5234 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5235 // All channels should be 100 sats capacity. But for the fee experiment,
5236 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5237 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5238 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5239 // so no matter how large are other channels,
5240 // the whole path will be limited by 100 sats with just these 2 conditions:
5241 // - channel 12 capacity is 250 sats
5242 // - fee for channel 6 is 150 sats
5243 // Let's test this by enforcing these 2 conditions and removing other limits.
5244 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5245 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5246 short_channel_id: 12,
5249 cltv_expiry_delta: 0,
5250 htlc_minimum_msat: 0,
5251 htlc_maximum_msat: 250_000,
5253 fee_proportional_millionths: 0,
5254 excess_data: Vec::new()
5256 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5257 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5258 short_channel_id: 13,
5261 cltv_expiry_delta: 0,
5262 htlc_minimum_msat: 0,
5263 htlc_maximum_msat: MAX_VALUE_MSAT,
5265 fee_proportional_millionths: 0,
5266 excess_data: Vec::new()
5269 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5270 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5271 short_channel_id: 6,
5274 cltv_expiry_delta: 0,
5275 htlc_minimum_msat: 0,
5276 htlc_maximum_msat: MAX_VALUE_MSAT,
5277 fee_base_msat: 150_000,
5278 fee_proportional_millionths: 0,
5279 excess_data: Vec::new()
5281 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5282 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5283 short_channel_id: 11,
5286 cltv_expiry_delta: 0,
5287 htlc_minimum_msat: 0,
5288 htlc_maximum_msat: MAX_VALUE_MSAT,
5290 fee_proportional_millionths: 0,
5291 excess_data: Vec::new()
5295 // Attempt to route more than available results in a failure.
5296 let route_params = RouteParameters::from_payment_params_and_value(
5297 payment_params.clone(), 210_000);
5298 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5299 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5300 &scorer, &Default::default(), &random_seed_bytes) {
5301 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5302 } else { panic!(); }
5306 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5307 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5308 max_total_routing_fee_msat: Some(149_999) };
5309 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5310 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5311 &scorer, &(), &random_seed_bytes) {
5312 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5313 } else { panic!(); }
5317 // Now, attempt to route 200 sats (exact amount we can route).
5318 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5319 max_total_routing_fee_msat: Some(150_000) };
5320 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5321 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5322 assert_eq!(route.paths.len(), 2);
5324 let mut total_amount_paid_msat = 0;
5325 for path in &route.paths {
5326 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5327 total_amount_paid_msat += path.final_value_msat();
5329 assert_eq!(total_amount_paid_msat, 200_000);
5330 assert_eq!(route.get_total_fees(), 150_000);
5335 fn mpp_with_last_hops() {
5336 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5337 // via a single last-hop route hint, we'd fail to route if we first collected routes
5338 // totaling close but not quite enough to fund the full payment.
5340 // This was because we considered last-hop hints to have exactly the sought payment amount
5341 // instead of the amount we were trying to collect, needlessly limiting our path searching
5342 // at the very first hop.
5344 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5345 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5346 // to only have the remaining to-collect amount in available liquidity.
5348 // This bug appeared in production in some specific channel configurations.
5349 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5350 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5351 let scorer = ln_test_utils::TestScorer::new();
5352 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5353 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5354 let config = UserConfig::default();
5355 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5356 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5357 src_node_id: nodes[2],
5358 short_channel_id: 42,
5359 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5360 cltv_expiry_delta: 42,
5361 htlc_minimum_msat: None,
5362 htlc_maximum_msat: None,
5363 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5365 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5366 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5367 // would first use the no-fee route and then fail to find a path along the second route as
5368 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5369 // under 5% of our payment amount.
5370 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5371 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5372 short_channel_id: 1,
5375 cltv_expiry_delta: (5 << 4) | 5,
5376 htlc_minimum_msat: 0,
5377 htlc_maximum_msat: 99_000,
5378 fee_base_msat: u32::max_value(),
5379 fee_proportional_millionths: u32::max_value(),
5380 excess_data: Vec::new()
5382 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5383 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5384 short_channel_id: 2,
5387 cltv_expiry_delta: (5 << 4) | 3,
5388 htlc_minimum_msat: 0,
5389 htlc_maximum_msat: 99_000,
5390 fee_base_msat: u32::max_value(),
5391 fee_proportional_millionths: u32::max_value(),
5392 excess_data: Vec::new()
5394 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5395 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5396 short_channel_id: 4,
5399 cltv_expiry_delta: (4 << 4) | 1,
5400 htlc_minimum_msat: 0,
5401 htlc_maximum_msat: MAX_VALUE_MSAT,
5403 fee_proportional_millionths: 0,
5404 excess_data: Vec::new()
5406 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5407 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5408 short_channel_id: 13,
5410 flags: 0|2, // Channel disabled
5411 cltv_expiry_delta: (13 << 4) | 1,
5412 htlc_minimum_msat: 0,
5413 htlc_maximum_msat: MAX_VALUE_MSAT,
5415 fee_proportional_millionths: 2000000,
5416 excess_data: Vec::new()
5419 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5421 let route_params = RouteParameters::from_payment_params_and_value(
5422 payment_params, 100_000);
5423 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5424 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5425 assert_eq!(route.paths.len(), 2);
5426 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5427 // Paths are manually ordered ordered by SCID, so:
5428 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5429 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5430 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5431 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5432 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5433 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5434 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5435 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5436 assert_eq!(route.get_total_fees(), 1);
5437 assert_eq!(route.get_total_amount(), 100_000);
5441 fn drop_lowest_channel_mpp_route_test() {
5442 // This test checks that low-capacity channel is dropped when after
5443 // path finding we realize that we found more capacity than we need.
5444 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5445 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5446 let scorer = ln_test_utils::TestScorer::new();
5447 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5448 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5449 let config = UserConfig::default();
5450 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5451 .with_max_channel_saturation_power_of_half(0);
5453 // We need a route consisting of 3 paths:
5454 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5456 // The first and the second paths should be sufficient, but the third should be
5457 // cheaper, so that we select it but drop later.
5459 // First, we set limits on these (previously unlimited) channels.
5460 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5462 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5463 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5464 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5465 short_channel_id: 1,
5468 cltv_expiry_delta: 0,
5469 htlc_minimum_msat: 0,
5470 htlc_maximum_msat: 100_000,
5472 fee_proportional_millionths: 0,
5473 excess_data: Vec::new()
5475 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5476 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5477 short_channel_id: 3,
5480 cltv_expiry_delta: 0,
5481 htlc_minimum_msat: 0,
5482 htlc_maximum_msat: 50_000,
5484 fee_proportional_millionths: 0,
5485 excess_data: Vec::new()
5488 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5489 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5490 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5491 short_channel_id: 12,
5494 cltv_expiry_delta: 0,
5495 htlc_minimum_msat: 0,
5496 htlc_maximum_msat: 60_000,
5498 fee_proportional_millionths: 0,
5499 excess_data: Vec::new()
5501 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5502 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5503 short_channel_id: 13,
5506 cltv_expiry_delta: 0,
5507 htlc_minimum_msat: 0,
5508 htlc_maximum_msat: 60_000,
5510 fee_proportional_millionths: 0,
5511 excess_data: Vec::new()
5514 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5515 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5516 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5517 short_channel_id: 2,
5520 cltv_expiry_delta: 0,
5521 htlc_minimum_msat: 0,
5522 htlc_maximum_msat: 20_000,
5524 fee_proportional_millionths: 0,
5525 excess_data: Vec::new()
5527 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5528 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5529 short_channel_id: 4,
5532 cltv_expiry_delta: 0,
5533 htlc_minimum_msat: 0,
5534 htlc_maximum_msat: 20_000,
5536 fee_proportional_millionths: 0,
5537 excess_data: Vec::new()
5541 // Attempt to route more than available results in a failure.
5542 let route_params = RouteParameters::from_payment_params_and_value(
5543 payment_params.clone(), 150_000);
5544 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5545 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5546 &scorer, &Default::default(), &random_seed_bytes) {
5547 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5548 } else { panic!(); }
5552 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5553 // Our algorithm should provide us with these 3 paths.
5554 let route_params = RouteParameters::from_payment_params_and_value(
5555 payment_params.clone(), 125_000);
5556 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5557 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5558 assert_eq!(route.paths.len(), 3);
5559 let mut total_amount_paid_msat = 0;
5560 for path in &route.paths {
5561 assert_eq!(path.hops.len(), 2);
5562 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5563 total_amount_paid_msat += path.final_value_msat();
5565 assert_eq!(total_amount_paid_msat, 125_000);
5569 // Attempt to route without the last small cheap channel
5570 let route_params = RouteParameters::from_payment_params_and_value(
5571 payment_params, 90_000);
5572 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5573 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5574 assert_eq!(route.paths.len(), 2);
5575 let mut total_amount_paid_msat = 0;
5576 for path in &route.paths {
5577 assert_eq!(path.hops.len(), 2);
5578 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5579 total_amount_paid_msat += path.final_value_msat();
5581 assert_eq!(total_amount_paid_msat, 90_000);
5586 fn min_criteria_consistency() {
5587 // Test that we don't use an inconsistent metric between updating and walking nodes during
5588 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5589 // was updated with a different criterion from the heap sorting, resulting in loops in
5590 // calculated paths. We test for that specific case here.
5592 // We construct a network that looks like this:
5594 // node2 -1(3)2- node3
5598 // node1 -1(5)2- node4 -1(1)2- node6
5604 // We create a loop on the side of our real path - our destination is node 6, with a
5605 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5606 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5607 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5608 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5609 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5610 // "previous hop" being set to node 3, creating a loop in the path.
5611 let secp_ctx = Secp256k1::new();
5612 let logger = Arc::new(ln_test_utils::TestLogger::new());
5613 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5614 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5615 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5616 let scorer = ln_test_utils::TestScorer::new();
5617 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5618 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5619 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5621 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5622 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5624 short_channel_id: 6,
5627 cltv_expiry_delta: (6 << 4) | 0,
5628 htlc_minimum_msat: 0,
5629 htlc_maximum_msat: MAX_VALUE_MSAT,
5631 fee_proportional_millionths: 0,
5632 excess_data: Vec::new()
5634 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5636 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5637 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5638 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5639 short_channel_id: 5,
5642 cltv_expiry_delta: (5 << 4) | 0,
5643 htlc_minimum_msat: 0,
5644 htlc_maximum_msat: MAX_VALUE_MSAT,
5646 fee_proportional_millionths: 0,
5647 excess_data: Vec::new()
5649 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5651 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5652 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5653 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5654 short_channel_id: 4,
5657 cltv_expiry_delta: (4 << 4) | 0,
5658 htlc_minimum_msat: 0,
5659 htlc_maximum_msat: MAX_VALUE_MSAT,
5661 fee_proportional_millionths: 0,
5662 excess_data: Vec::new()
5664 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5666 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5667 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5668 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5669 short_channel_id: 3,
5672 cltv_expiry_delta: (3 << 4) | 0,
5673 htlc_minimum_msat: 0,
5674 htlc_maximum_msat: MAX_VALUE_MSAT,
5676 fee_proportional_millionths: 0,
5677 excess_data: Vec::new()
5679 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5681 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5682 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5683 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5684 short_channel_id: 2,
5687 cltv_expiry_delta: (2 << 4) | 0,
5688 htlc_minimum_msat: 0,
5689 htlc_maximum_msat: MAX_VALUE_MSAT,
5691 fee_proportional_millionths: 0,
5692 excess_data: Vec::new()
5695 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5696 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5697 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5698 short_channel_id: 1,
5701 cltv_expiry_delta: (1 << 4) | 0,
5702 htlc_minimum_msat: 100,
5703 htlc_maximum_msat: MAX_VALUE_MSAT,
5705 fee_proportional_millionths: 0,
5706 excess_data: Vec::new()
5708 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5711 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5712 let route_params = RouteParameters::from_payment_params_and_value(
5713 payment_params, 10_000);
5714 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5715 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5716 assert_eq!(route.paths.len(), 1);
5717 assert_eq!(route.paths[0].hops.len(), 3);
5719 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5720 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5721 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5722 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5723 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5724 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5726 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5727 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5728 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5729 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5730 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5731 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5733 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5734 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5735 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5736 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5737 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5738 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5744 fn exact_fee_liquidity_limit() {
5745 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5746 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5747 // we calculated fees on a higher value, resulting in us ignoring such paths.
5748 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5749 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5750 let scorer = ln_test_utils::TestScorer::new();
5751 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5752 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5753 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5755 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5757 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5758 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5759 short_channel_id: 2,
5762 cltv_expiry_delta: 0,
5763 htlc_minimum_msat: 0,
5764 htlc_maximum_msat: 85_000,
5766 fee_proportional_millionths: 0,
5767 excess_data: Vec::new()
5770 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5771 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5772 short_channel_id: 12,
5775 cltv_expiry_delta: (4 << 4) | 1,
5776 htlc_minimum_msat: 0,
5777 htlc_maximum_msat: 270_000,
5779 fee_proportional_millionths: 1000000,
5780 excess_data: Vec::new()
5784 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5785 // 200% fee charged channel 13 in the 1-to-2 direction.
5786 let mut route_params = RouteParameters::from_payment_params_and_value(
5787 payment_params, 90_000);
5788 route_params.max_total_routing_fee_msat = Some(90_000*2);
5789 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5790 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5791 assert_eq!(route.paths.len(), 1);
5792 assert_eq!(route.paths[0].hops.len(), 2);
5794 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5795 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5796 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5797 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5798 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5799 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5801 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5802 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5803 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5804 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5805 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5806 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5811 fn htlc_max_reduction_below_min() {
5812 // Test that if, while walking the graph, we reduce the value being sent to meet an
5813 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5814 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5815 // resulting in us thinking there is no possible path, even if other paths exist.
5816 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5817 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5818 let scorer = ln_test_utils::TestScorer::new();
5819 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5820 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5821 let config = UserConfig::default();
5822 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5824 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5825 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5826 // then try to send 90_000.
5827 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5828 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5829 short_channel_id: 2,
5832 cltv_expiry_delta: 0,
5833 htlc_minimum_msat: 0,
5834 htlc_maximum_msat: 80_000,
5836 fee_proportional_millionths: 0,
5837 excess_data: Vec::new()
5839 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5840 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5841 short_channel_id: 4,
5844 cltv_expiry_delta: (4 << 4) | 1,
5845 htlc_minimum_msat: 90_000,
5846 htlc_maximum_msat: MAX_VALUE_MSAT,
5848 fee_proportional_millionths: 0,
5849 excess_data: Vec::new()
5853 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5854 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5855 // expensive) channels 12-13 path.
5856 let mut route_params = RouteParameters::from_payment_params_and_value(
5857 payment_params, 90_000);
5858 route_params.max_total_routing_fee_msat = Some(90_000*2);
5859 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5860 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5861 assert_eq!(route.paths.len(), 1);
5862 assert_eq!(route.paths[0].hops.len(), 2);
5864 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5865 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5866 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5867 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5868 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5869 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5871 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5872 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5873 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5874 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5875 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5876 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5881 fn multiple_direct_first_hops() {
5882 // Previously we'd only ever considered one first hop path per counterparty.
5883 // However, as we don't restrict users to one channel per peer, we really need to support
5884 // looking at all first hop paths.
5885 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5886 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5887 // route over multiple channels with the same first hop.
5888 let secp_ctx = Secp256k1::new();
5889 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5890 let logger = Arc::new(ln_test_utils::TestLogger::new());
5891 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5892 let scorer = ln_test_utils::TestScorer::new();
5893 let config = UserConfig::default();
5894 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5895 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5896 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5899 let route_params = RouteParameters::from_payment_params_and_value(
5900 payment_params.clone(), 100_000);
5901 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5902 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
5903 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
5904 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5905 assert_eq!(route.paths.len(), 1);
5906 assert_eq!(route.paths[0].hops.len(), 1);
5908 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5909 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
5910 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5913 let route_params = RouteParameters::from_payment_params_and_value(
5914 payment_params.clone(), 100_000);
5915 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5916 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5917 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5918 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5919 assert_eq!(route.paths.len(), 2);
5920 assert_eq!(route.paths[0].hops.len(), 1);
5921 assert_eq!(route.paths[1].hops.len(), 1);
5923 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
5924 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
5926 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5927 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
5929 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
5930 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
5934 // If we have a bunch of outbound channels to the same node, where most are not
5935 // sufficient to pay the full payment, but one is, we should default to just using the
5936 // one single channel that has sufficient balance, avoiding MPP.
5938 // If we have several options above the 3xpayment value threshold, we should pick the
5939 // smallest of them, avoiding further fragmenting our available outbound balance to
5941 let route_params = RouteParameters::from_payment_params_and_value(
5942 payment_params, 100_000);
5943 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
5944 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5945 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5946 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5947 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5948 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5949 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5950 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5951 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5952 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5953 assert_eq!(route.paths.len(), 1);
5954 assert_eq!(route.paths[0].hops.len(), 1);
5956 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
5957 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5958 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
5963 fn prefers_shorter_route_with_higher_fees() {
5964 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5965 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5966 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
5968 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5969 let scorer = ln_test_utils::TestScorer::new();
5970 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5971 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5972 let route_params = RouteParameters::from_payment_params_and_value(
5973 payment_params.clone(), 100);
5974 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5975 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5976 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5978 assert_eq!(route.get_total_fees(), 100);
5979 assert_eq!(route.get_total_amount(), 100);
5980 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5982 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5983 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5984 let scorer = FixedPenaltyScorer::with_penalty(100);
5985 let route_params = RouteParameters::from_payment_params_and_value(
5986 payment_params, 100);
5987 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
5988 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5989 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5991 assert_eq!(route.get_total_fees(), 300);
5992 assert_eq!(route.get_total_amount(), 100);
5993 assert_eq!(path, vec![2, 4, 7, 10]);
5996 struct BadChannelScorer {
5997 short_channel_id: u64,
6001 impl Writeable for BadChannelScorer {
6002 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6004 impl ScoreLookUp for BadChannelScorer {
6005 type ScoreParams = ();
6006 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6007 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
6011 struct BadNodeScorer {
6016 impl Writeable for BadNodeScorer {
6017 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6020 impl ScoreLookUp for BadNodeScorer {
6021 type ScoreParams = ();
6022 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6023 if *target == self.node_id { u64::max_value() } else { 0 }
6028 fn avoids_routing_through_bad_channels_and_nodes() {
6029 let (secp_ctx, network, _, _, logger) = build_graph();
6030 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6031 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6032 let network_graph = network.read_only();
6034 // A path to nodes[6] exists when no penalties are applied to any channel.
6035 let scorer = ln_test_utils::TestScorer::new();
6036 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6037 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6038 let route_params = RouteParameters::from_payment_params_and_value(
6039 payment_params, 100);
6040 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6041 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6042 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6044 assert_eq!(route.get_total_fees(), 100);
6045 assert_eq!(route.get_total_amount(), 100);
6046 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6048 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6049 let scorer = BadChannelScorer { short_channel_id: 6 };
6050 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6051 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6052 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6054 assert_eq!(route.get_total_fees(), 300);
6055 assert_eq!(route.get_total_amount(), 100);
6056 assert_eq!(path, vec![2, 4, 7, 10]);
6058 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6059 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6060 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6061 &scorer, &Default::default(), &random_seed_bytes) {
6062 Err(LightningError { err, .. } ) => {
6063 assert_eq!(err, "Failed to find a path to the given destination");
6065 Ok(_) => panic!("Expected error"),
6070 fn total_fees_single_path() {
6072 paths: vec![Path { hops: vec![
6074 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6075 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6076 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6079 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6080 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6081 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6084 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6085 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6086 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6088 ], blinded_tail: None }],
6092 assert_eq!(route.get_total_fees(), 250);
6093 assert_eq!(route.get_total_amount(), 225);
6097 fn total_fees_multi_path() {
6099 paths: vec![Path { hops: vec![
6101 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6102 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6103 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6106 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6107 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6108 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6110 ], blinded_tail: None }, Path { hops: vec![
6112 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6113 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6114 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6117 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6118 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6119 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6121 ], blinded_tail: None }],
6125 assert_eq!(route.get_total_fees(), 200);
6126 assert_eq!(route.get_total_amount(), 300);
6130 fn total_empty_route_no_panic() {
6131 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6132 // would both panic if the route was completely empty. We test to ensure they return 0
6133 // here, even though its somewhat nonsensical as a route.
6134 let route = Route { paths: Vec::new(), route_params: None };
6136 assert_eq!(route.get_total_fees(), 0);
6137 assert_eq!(route.get_total_amount(), 0);
6141 fn limits_total_cltv_delta() {
6142 let (secp_ctx, network, _, _, logger) = build_graph();
6143 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6144 let network_graph = network.read_only();
6146 let scorer = ln_test_utils::TestScorer::new();
6148 // Make sure that generally there is at least one route available
6149 let feasible_max_total_cltv_delta = 1008;
6150 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6151 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6152 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6153 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6154 let route_params = RouteParameters::from_payment_params_and_value(
6155 feasible_payment_params, 100);
6156 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6157 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6158 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6159 assert_ne!(path.len(), 0);
6161 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6162 let fail_max_total_cltv_delta = 23;
6163 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6164 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6165 let route_params = RouteParameters::from_payment_params_and_value(
6166 fail_payment_params, 100);
6167 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6168 &Default::default(), &random_seed_bytes)
6170 Err(LightningError { err, .. } ) => {
6171 assert_eq!(err, "Failed to find a path to the given destination");
6173 Ok(_) => panic!("Expected error"),
6178 fn avoids_recently_failed_paths() {
6179 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6180 // randomly inserting channels into it until we can't find a route anymore.
6181 let (secp_ctx, network, _, _, logger) = build_graph();
6182 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6183 let network_graph = network.read_only();
6185 let scorer = ln_test_utils::TestScorer::new();
6186 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6187 .with_max_path_count(1);
6188 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6189 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6191 // We should be able to find a route initially, and then after we fail a few random
6192 // channels eventually we won't be able to any longer.
6193 let route_params = RouteParameters::from_payment_params_and_value(
6194 payment_params.clone(), 100);
6195 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6196 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6198 let route_params = RouteParameters::from_payment_params_and_value(
6199 payment_params.clone(), 100);
6200 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6201 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6203 for chan in route.paths[0].hops.iter() {
6204 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6206 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6207 % route.paths[0].hops.len();
6208 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6214 fn limits_path_length() {
6215 let (secp_ctx, network, _, _, logger) = build_line_graph();
6216 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6217 let network_graph = network.read_only();
6219 let scorer = ln_test_utils::TestScorer::new();
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 // First check we can actually create a long route on this graph.
6224 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6225 let route_params = RouteParameters::from_payment_params_and_value(
6226 feasible_payment_params, 100);
6227 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6228 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6229 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6230 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6232 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6233 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6234 let route_params = RouteParameters::from_payment_params_and_value(
6235 fail_payment_params, 100);
6236 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6237 &Default::default(), &random_seed_bytes)
6239 Err(LightningError { err, .. } ) => {
6240 assert_eq!(err, "Failed to find a path to the given destination");
6242 Ok(_) => panic!("Expected error"),
6247 fn adds_and_limits_cltv_offset() {
6248 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6249 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6251 let scorer = ln_test_utils::TestScorer::new();
6253 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6254 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6255 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6256 let route_params = RouteParameters::from_payment_params_and_value(
6257 payment_params.clone(), 100);
6258 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6259 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6260 assert_eq!(route.paths.len(), 1);
6262 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6264 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6265 let mut route_default = route.clone();
6266 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6267 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6268 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6269 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6270 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6272 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6273 let mut route_limited = route.clone();
6274 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6275 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6276 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6277 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6278 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6282 fn adds_plausible_cltv_offset() {
6283 let (secp_ctx, network, _, _, logger) = build_graph();
6284 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6285 let network_graph = network.read_only();
6286 let network_nodes = network_graph.nodes();
6287 let network_channels = network_graph.channels();
6288 let scorer = ln_test_utils::TestScorer::new();
6289 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6290 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6291 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6293 let route_params = RouteParameters::from_payment_params_and_value(
6294 payment_params.clone(), 100);
6295 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6296 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6297 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6299 let mut path_plausibility = vec![];
6301 for p in route.paths {
6302 // 1. Select random observation point
6303 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6304 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6306 prng.process_in_place(&mut random_bytes);
6307 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6308 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6310 // 2. Calculate what CLTV expiry delta we would observe there
6311 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6313 // 3. Starting from the observation point, find candidate paths
6314 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6315 candidates.push_back((observation_point, vec![]));
6317 let mut found_plausible_candidate = false;
6319 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6320 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6321 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6322 found_plausible_candidate = true;
6323 break 'candidate_loop;
6327 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6328 for channel_id in &cur_node.channels {
6329 if let Some(channel_info) = network_channels.get(&channel_id) {
6330 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6331 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6332 if cur_path_cltv_deltas.iter().sum::<u32>()
6333 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6334 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6335 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6336 candidates.push_back((*next_id, new_path_cltv_deltas));
6344 path_plausibility.push(found_plausible_candidate);
6346 assert!(path_plausibility.iter().all(|x| *x));
6350 fn builds_correct_path_from_hops() {
6351 let (secp_ctx, network, _, _, logger) = build_graph();
6352 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6353 let network_graph = network.read_only();
6355 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6356 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6358 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6359 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6360 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6361 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6362 Arc::clone(&logger), &random_seed_bytes).unwrap();
6363 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6364 assert_eq!(hops.len(), route.paths[0].hops.len());
6365 for (idx, hop_pubkey) in hops.iter().enumerate() {
6366 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6371 fn avoids_saturating_channels() {
6372 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6373 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6374 let decay_params = ProbabilisticScoringDecayParameters::default();
6375 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6377 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6378 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6379 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6380 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6381 short_channel_id: 4,
6384 cltv_expiry_delta: (4 << 4) | 1,
6385 htlc_minimum_msat: 0,
6386 htlc_maximum_msat: 250_000_000,
6388 fee_proportional_millionths: 0,
6389 excess_data: Vec::new()
6391 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6392 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6393 short_channel_id: 13,
6396 cltv_expiry_delta: (13 << 4) | 1,
6397 htlc_minimum_msat: 0,
6398 htlc_maximum_msat: 250_000_000,
6400 fee_proportional_millionths: 0,
6401 excess_data: Vec::new()
6404 let config = UserConfig::default();
6405 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6406 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6407 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6408 // 100,000 sats is less than the available liquidity on each channel, set above.
6409 let route_params = RouteParameters::from_payment_params_and_value(
6410 payment_params, 100_000_000);
6411 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6412 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6413 assert_eq!(route.paths.len(), 2);
6414 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6415 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6418 #[cfg(not(feature = "no-std"))]
6419 pub(super) fn random_init_seed() -> u64 {
6420 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6421 use core::hash::{BuildHasher, Hasher};
6422 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6423 println!("Using seed of {}", seed);
6428 #[cfg(not(feature = "no-std"))]
6429 fn generate_routes() {
6430 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6432 let logger = ln_test_utils::TestLogger::new();
6433 let graph = match super::bench_utils::read_network_graph(&logger) {
6441 let params = ProbabilisticScoringFeeParameters::default();
6442 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6443 let features = super::Bolt11InvoiceFeatures::empty();
6445 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6449 #[cfg(not(feature = "no-std"))]
6450 fn generate_routes_mpp() {
6451 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6453 let logger = ln_test_utils::TestLogger::new();
6454 let graph = match super::bench_utils::read_network_graph(&logger) {
6462 let params = ProbabilisticScoringFeeParameters::default();
6463 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6464 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6466 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6470 #[cfg(not(feature = "no-std"))]
6471 fn generate_large_mpp_routes() {
6472 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6474 let logger = ln_test_utils::TestLogger::new();
6475 let graph = match super::bench_utils::read_network_graph(&logger) {
6483 let params = ProbabilisticScoringFeeParameters::default();
6484 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6485 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6487 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6491 fn honors_manual_penalties() {
6492 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6493 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6495 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6496 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6498 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6499 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6501 // First check set manual penalties are returned by the scorer.
6502 let usage = ChannelUsage {
6504 inflight_htlc_msat: 0,
6505 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6507 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6508 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6509 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6511 // Then check we can get a normal route
6512 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6513 let route_params = RouteParameters::from_payment_params_and_value(
6514 payment_params, 100);
6515 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6516 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6517 assert!(route.is_ok());
6519 // Then check that we can't get a route if we ban an intermediate node.
6520 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6521 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6522 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6523 assert!(route.is_err());
6525 // Finally make sure we can route again, when we remove the ban.
6526 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6527 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6528 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6529 assert!(route.is_ok());
6533 fn abide_by_route_hint_max_htlc() {
6534 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6535 // params in the final route.
6536 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6537 let netgraph = network_graph.read_only();
6538 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6539 let scorer = ln_test_utils::TestScorer::new();
6540 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6541 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6542 let config = UserConfig::default();
6544 let max_htlc_msat = 50_000;
6545 let route_hint_1 = RouteHint(vec![RouteHintHop {
6546 src_node_id: nodes[2],
6547 short_channel_id: 42,
6550 proportional_millionths: 0,
6552 cltv_expiry_delta: 10,
6553 htlc_minimum_msat: None,
6554 htlc_maximum_msat: Some(max_htlc_msat),
6556 let dest_node_id = ln_test_utils::pubkey(42);
6557 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6558 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6559 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6561 // Make sure we'll error if our route hints don't have enough liquidity according to their
6562 // htlc_maximum_msat.
6563 let mut route_params = RouteParameters::from_payment_params_and_value(
6564 payment_params, max_htlc_msat + 1);
6565 route_params.max_total_routing_fee_msat = None;
6566 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6567 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6570 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6571 } else { panic!(); }
6573 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6574 let mut route_hint_2 = route_hint_1.clone();
6575 route_hint_2.0[0].short_channel_id = 43;
6576 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6577 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6578 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6579 let mut route_params = RouteParameters::from_payment_params_and_value(
6580 payment_params, max_htlc_msat + 1);
6581 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6582 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6583 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6584 assert_eq!(route.paths.len(), 2);
6585 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6586 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6590 fn direct_channel_to_hints_with_max_htlc() {
6591 // Check that if we have a first hop channel peer that's connected to multiple provided route
6592 // hints, that we properly split the payment between the route hints if needed.
6593 let logger = Arc::new(ln_test_utils::TestLogger::new());
6594 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6595 let scorer = ln_test_utils::TestScorer::new();
6596 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6597 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6598 let config = UserConfig::default();
6600 let our_node_id = ln_test_utils::pubkey(42);
6601 let intermed_node_id = ln_test_utils::pubkey(43);
6602 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6604 let amt_msat = 900_000;
6605 let max_htlc_msat = 500_000;
6606 let route_hint_1 = RouteHint(vec![RouteHintHop {
6607 src_node_id: intermed_node_id,
6608 short_channel_id: 44,
6611 proportional_millionths: 0,
6613 cltv_expiry_delta: 10,
6614 htlc_minimum_msat: None,
6615 htlc_maximum_msat: Some(max_htlc_msat),
6617 src_node_id: intermed_node_id,
6618 short_channel_id: 45,
6621 proportional_millionths: 0,
6623 cltv_expiry_delta: 10,
6624 htlc_minimum_msat: None,
6625 // Check that later route hint max htlcs don't override earlier ones
6626 htlc_maximum_msat: Some(max_htlc_msat - 50),
6628 let mut route_hint_2 = route_hint_1.clone();
6629 route_hint_2.0[0].short_channel_id = 46;
6630 route_hint_2.0[1].short_channel_id = 47;
6631 let dest_node_id = ln_test_utils::pubkey(44);
6632 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6633 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6634 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6636 let route_params = RouteParameters::from_payment_params_and_value(
6637 payment_params, amt_msat);
6638 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6639 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6640 &Default::default(), &random_seed_bytes).unwrap();
6641 assert_eq!(route.paths.len(), 2);
6642 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6643 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6644 assert_eq!(route.get_total_amount(), amt_msat);
6646 // Re-run but with two first hop channels connected to the same route hint peers that must be
6648 let first_hops = vec![
6649 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6650 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6652 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6653 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6654 &Default::default(), &random_seed_bytes).unwrap();
6655 assert_eq!(route.paths.len(), 2);
6656 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6657 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6658 assert_eq!(route.get_total_amount(), amt_msat);
6660 // Make sure this works for blinded route hints.
6661 let blinded_path = BlindedPath {
6662 introduction_node_id: intermed_node_id,
6663 blinding_point: ln_test_utils::pubkey(42),
6665 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6666 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6669 let blinded_payinfo = BlindedPayInfo {
6671 fee_proportional_millionths: 0,
6672 htlc_minimum_msat: 1,
6673 htlc_maximum_msat: max_htlc_msat,
6674 cltv_expiry_delta: 10,
6675 features: BlindedHopFeatures::empty(),
6677 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6678 let payment_params = PaymentParameters::blinded(vec![
6679 (blinded_payinfo.clone(), blinded_path.clone()),
6680 (blinded_payinfo.clone(), blinded_path.clone())])
6681 .with_bolt12_features(bolt12_features).unwrap();
6682 let route_params = RouteParameters::from_payment_params_and_value(
6683 payment_params, amt_msat);
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);
6694 fn blinded_route_ser() {
6695 let blinded_path_1 = BlindedPath {
6696 introduction_node_id: ln_test_utils::pubkey(42),
6697 blinding_point: ln_test_utils::pubkey(43),
6699 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6700 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6703 let blinded_path_2 = BlindedPath {
6704 introduction_node_id: ln_test_utils::pubkey(46),
6705 blinding_point: ln_test_utils::pubkey(47),
6707 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6708 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6711 // (De)serialize a Route with 1 blinded path out of two total paths.
6712 let mut route = Route { paths: vec![Path {
6713 hops: vec![RouteHop {
6714 pubkey: ln_test_utils::pubkey(50),
6715 node_features: NodeFeatures::empty(),
6716 short_channel_id: 42,
6717 channel_features: ChannelFeatures::empty(),
6719 cltv_expiry_delta: 0,
6720 maybe_announced_channel: true,
6722 blinded_tail: Some(BlindedTail {
6723 hops: blinded_path_1.blinded_hops,
6724 blinding_point: blinded_path_1.blinding_point,
6725 excess_final_cltv_expiry_delta: 40,
6726 final_value_msat: 100,
6728 hops: vec![RouteHop {
6729 pubkey: ln_test_utils::pubkey(51),
6730 node_features: NodeFeatures::empty(),
6731 short_channel_id: 43,
6732 channel_features: ChannelFeatures::empty(),
6734 cltv_expiry_delta: 0,
6735 maybe_announced_channel: true,
6736 }], blinded_tail: None }],
6739 let encoded_route = route.encode();
6740 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6741 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6742 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6744 // (De)serialize a Route with two paths, each containing a blinded tail.
6745 route.paths[1].blinded_tail = Some(BlindedTail {
6746 hops: blinded_path_2.blinded_hops,
6747 blinding_point: blinded_path_2.blinding_point,
6748 excess_final_cltv_expiry_delta: 41,
6749 final_value_msat: 101,
6751 let encoded_route = route.encode();
6752 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6753 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6754 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6758 fn blinded_path_inflight_processing() {
6759 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6760 // account for the blinded tail's final amount_msat.
6761 let mut inflight_htlcs = InFlightHtlcs::new();
6762 let blinded_path = BlindedPath {
6763 introduction_node_id: ln_test_utils::pubkey(43),
6764 blinding_point: ln_test_utils::pubkey(48),
6765 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6768 hops: vec![RouteHop {
6769 pubkey: ln_test_utils::pubkey(42),
6770 node_features: NodeFeatures::empty(),
6771 short_channel_id: 42,
6772 channel_features: ChannelFeatures::empty(),
6774 cltv_expiry_delta: 0,
6775 maybe_announced_channel: false,
6778 pubkey: blinded_path.introduction_node_id,
6779 node_features: NodeFeatures::empty(),
6780 short_channel_id: 43,
6781 channel_features: ChannelFeatures::empty(),
6783 cltv_expiry_delta: 0,
6784 maybe_announced_channel: false,
6786 blinded_tail: Some(BlindedTail {
6787 hops: blinded_path.blinded_hops,
6788 blinding_point: blinded_path.blinding_point,
6789 excess_final_cltv_expiry_delta: 0,
6790 final_value_msat: 200,
6793 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6794 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6795 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6799 fn blinded_path_cltv_shadow_offset() {
6800 // Make sure we add a shadow offset when sending to blinded paths.
6801 let blinded_path = BlindedPath {
6802 introduction_node_id: ln_test_utils::pubkey(43),
6803 blinding_point: ln_test_utils::pubkey(44),
6805 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6806 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6809 let mut route = Route { paths: vec![Path {
6810 hops: vec![RouteHop {
6811 pubkey: ln_test_utils::pubkey(42),
6812 node_features: NodeFeatures::empty(),
6813 short_channel_id: 42,
6814 channel_features: ChannelFeatures::empty(),
6816 cltv_expiry_delta: 0,
6817 maybe_announced_channel: false,
6820 pubkey: blinded_path.introduction_node_id,
6821 node_features: NodeFeatures::empty(),
6822 short_channel_id: 43,
6823 channel_features: ChannelFeatures::empty(),
6825 cltv_expiry_delta: 0,
6826 maybe_announced_channel: false,
6829 blinded_tail: Some(BlindedTail {
6830 hops: blinded_path.blinded_hops,
6831 blinding_point: blinded_path.blinding_point,
6832 excess_final_cltv_expiry_delta: 0,
6833 final_value_msat: 200,
6835 }], route_params: None};
6837 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6838 let (_, network_graph, _, _, _) = build_line_graph();
6839 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6840 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6841 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6845 fn simple_blinded_route_hints() {
6846 do_simple_blinded_route_hints(1);
6847 do_simple_blinded_route_hints(2);
6848 do_simple_blinded_route_hints(3);
6851 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6852 // Check that we can generate a route to a blinded path with the expected hops.
6853 let (secp_ctx, network, _, _, logger) = build_graph();
6854 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6855 let network_graph = network.read_only();
6857 let scorer = ln_test_utils::TestScorer::new();
6858 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6859 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6861 let mut blinded_path = BlindedPath {
6862 introduction_node_id: nodes[2],
6863 blinding_point: ln_test_utils::pubkey(42),
6864 blinded_hops: Vec::with_capacity(num_blinded_hops),
6866 for i in 0..num_blinded_hops {
6867 blinded_path.blinded_hops.push(
6868 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6871 let blinded_payinfo = BlindedPayInfo {
6873 fee_proportional_millionths: 500,
6874 htlc_minimum_msat: 1000,
6875 htlc_maximum_msat: 100_000_000,
6876 cltv_expiry_delta: 15,
6877 features: BlindedHopFeatures::empty(),
6880 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6881 let route_params = RouteParameters::from_payment_params_and_value(
6882 payment_params, 1001);
6883 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6884 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6885 assert_eq!(route.paths.len(), 1);
6886 assert_eq!(route.paths[0].hops.len(), 2);
6888 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6889 assert_eq!(tail.hops, blinded_path.blinded_hops);
6890 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6891 assert_eq!(tail.final_value_msat, 1001);
6893 let final_hop = route.paths[0].hops.last().unwrap();
6894 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6895 if tail.hops.len() > 1 {
6896 assert_eq!(final_hop.fee_msat,
6897 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6898 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
6900 assert_eq!(final_hop.fee_msat, 0);
6901 assert_eq!(final_hop.cltv_expiry_delta, 0);
6906 fn blinded_path_routing_errors() {
6907 // Check that we can generate a route to a blinded path with the expected hops.
6908 let (secp_ctx, network, _, _, logger) = build_graph();
6909 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6910 let network_graph = network.read_only();
6912 let scorer = ln_test_utils::TestScorer::new();
6913 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6914 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6916 let mut invalid_blinded_path = BlindedPath {
6917 introduction_node_id: nodes[2],
6918 blinding_point: ln_test_utils::pubkey(42),
6920 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
6923 let blinded_payinfo = BlindedPayInfo {
6925 fee_proportional_millionths: 500,
6926 htlc_minimum_msat: 1000,
6927 htlc_maximum_msat: 100_000_000,
6928 cltv_expiry_delta: 15,
6929 features: BlindedHopFeatures::empty(),
6932 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
6933 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
6934 let payment_params = PaymentParameters::blinded(vec![
6935 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
6936 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
6937 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6938 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6939 &scorer, &Default::default(), &random_seed_bytes)
6941 Err(LightningError { err, .. }) => {
6942 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
6944 _ => panic!("Expected error")
6947 invalid_blinded_path.introduction_node_id = our_id;
6948 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
6949 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6950 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6951 &Default::default(), &random_seed_bytes)
6953 Err(LightningError { err, .. }) => {
6954 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
6956 _ => panic!("Expected error")
6959 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
6960 invalid_blinded_path.blinded_hops.clear();
6961 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
6962 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
6963 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6964 &Default::default(), &random_seed_bytes)
6966 Err(LightningError { err, .. }) => {
6967 assert_eq!(err, "0-hop blinded path provided");
6969 _ => panic!("Expected error")
6974 fn matching_intro_node_paths_provided() {
6975 // Check that if multiple blinded paths with the same intro node are provided in payment
6976 // parameters, we'll return the correct paths in the resulting MPP route.
6977 let (secp_ctx, network, _, _, logger) = build_graph();
6978 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6979 let network_graph = network.read_only();
6981 let scorer = ln_test_utils::TestScorer::new();
6982 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6983 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6984 let config = UserConfig::default();
6986 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6987 let blinded_path_1 = BlindedPath {
6988 introduction_node_id: nodes[2],
6989 blinding_point: ln_test_utils::pubkey(42),
6991 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
6992 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
6995 let blinded_payinfo_1 = BlindedPayInfo {
6997 fee_proportional_millionths: 0,
6998 htlc_minimum_msat: 0,
6999 htlc_maximum_msat: 30_000,
7000 cltv_expiry_delta: 0,
7001 features: BlindedHopFeatures::empty(),
7004 let mut blinded_path_2 = blinded_path_1.clone();
7005 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7006 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7007 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7009 let blinded_hints = vec![
7010 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7011 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7013 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7014 .with_bolt12_features(bolt12_features.clone()).unwrap();
7016 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7017 route_params.max_total_routing_fee_msat = Some(100_000);
7018 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7019 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7020 assert_eq!(route.paths.len(), 2);
7021 let mut total_amount_paid_msat = 0;
7022 for path in route.paths.into_iter() {
7023 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7024 if let Some(bt) = &path.blinded_tail {
7025 assert_eq!(bt.blinding_point,
7026 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7027 .map(|(_, bp)| bp.blinding_point).unwrap());
7028 } else { panic!(); }
7029 total_amount_paid_msat += path.final_value_msat();
7031 assert_eq!(total_amount_paid_msat, 100_000);
7035 fn direct_to_intro_node() {
7036 // This previously caused a debug panic in the router when asserting
7037 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7038 // direct channels we failed to account for the fee charged for use of the blinded path.
7041 // node0 -1(1)2 - node1
7042 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7043 // doesn't account for the blinded path fee.
7045 let secp_ctx = Secp256k1::new();
7046 let logger = Arc::new(ln_test_utils::TestLogger::new());
7047 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7048 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7049 let scorer = ln_test_utils::TestScorer::new();
7050 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7051 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7053 let amt_msat = 10_000_000;
7054 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7055 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7056 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7057 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7058 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7059 short_channel_id: 1,
7062 cltv_expiry_delta: 42,
7063 htlc_minimum_msat: 1_000,
7064 htlc_maximum_msat: 10_000_000,
7066 fee_proportional_millionths: 0,
7067 excess_data: Vec::new()
7069 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7070 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7071 short_channel_id: 1,
7074 cltv_expiry_delta: 42,
7075 htlc_minimum_msat: 1_000,
7076 htlc_maximum_msat: 10_000_000,
7078 fee_proportional_millionths: 0,
7079 excess_data: Vec::new()
7081 let first_hops = vec![
7082 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7084 let blinded_path = BlindedPath {
7085 introduction_node_id: nodes[1],
7086 blinding_point: ln_test_utils::pubkey(42),
7088 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7089 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7092 let blinded_payinfo = BlindedPayInfo {
7093 fee_base_msat: 1000,
7094 fee_proportional_millionths: 0,
7095 htlc_minimum_msat: 1000,
7096 htlc_maximum_msat: MAX_VALUE_MSAT,
7097 cltv_expiry_delta: 0,
7098 features: BlindedHopFeatures::empty(),
7100 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7102 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7104 let netgraph = network_graph.read_only();
7105 let route_params = RouteParameters::from_payment_params_and_value(
7106 payment_params.clone(), amt_msat);
7107 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7108 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7109 &Default::default(), &random_seed_bytes) {
7110 assert_eq!(err, "Failed to find a path to the given destination");
7111 } else { panic!("Expected error") }
7113 // Sending an exact amount accounting for the blinded path fee works.
7114 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7115 let route_params = RouteParameters::from_payment_params_and_value(
7116 payment_params, amt_minus_blinded_path_fee);
7117 let route = get_route(&nodes[0], &route_params, &netgraph,
7118 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7119 &Default::default(), &random_seed_bytes).unwrap();
7120 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7121 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7125 fn direct_to_matching_intro_nodes() {
7126 // This previously caused us to enter `unreachable` code in the following situation:
7127 // 1. We add a route candidate for intro_node contributing a high amount
7128 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7129 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7130 // amount, and update our route candidate for intro_node for the lower amount
7131 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7132 // lower contribution amount, but fail (this was previously caused by failure to account for
7133 // blinded path fees when adding first_hop<>intro_node candidates)
7134 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7135 // candidate still thinks its path is contributing the original higher amount. This caused us
7136 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7138 let secp_ctx = Secp256k1::new();
7139 let logger = Arc::new(ln_test_utils::TestLogger::new());
7140 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7141 let scorer = ln_test_utils::TestScorer::new();
7142 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7143 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7144 let config = UserConfig::default();
7146 // Values are taken from the fuzz input that uncovered this panic.
7147 let amt_msat = 21_7020_5185_1403_2640;
7148 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7149 let first_hops = vec![
7150 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7151 18446744073709551615)];
7153 let blinded_path = BlindedPath {
7154 introduction_node_id: nodes[1],
7155 blinding_point: ln_test_utils::pubkey(42),
7157 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7158 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7161 let blinded_payinfo = BlindedPayInfo {
7162 fee_base_msat: 5046_2720,
7163 fee_proportional_millionths: 0,
7164 htlc_minimum_msat: 4503_5996_2737_0496,
7165 htlc_maximum_msat: 45_0359_9627_3704_9600,
7166 cltv_expiry_delta: 0,
7167 features: BlindedHopFeatures::empty(),
7169 let mut blinded_hints = vec![
7170 (blinded_payinfo.clone(), blinded_path.clone()),
7171 (blinded_payinfo.clone(), blinded_path.clone()),
7173 blinded_hints[1].0.fee_base_msat = 419_4304;
7174 blinded_hints[1].0.fee_proportional_millionths = 257;
7175 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7176 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7177 blinded_hints[1].0.cltv_expiry_delta = 0;
7179 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7180 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7181 .with_bolt12_features(bolt12_features.clone()).unwrap();
7183 let netgraph = network_graph.read_only();
7184 let route_params = RouteParameters::from_payment_params_and_value(
7185 payment_params, amt_msat);
7186 let route = get_route(&nodes[0], &route_params, &netgraph,
7187 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7188 &Default::default(), &random_seed_bytes).unwrap();
7189 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7190 assert_eq!(route.get_total_amount(), amt_msat);
7194 fn we_are_intro_node_candidate_hops() {
7195 // This previously led to a panic in the router because we'd generate a Path with only a
7196 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7197 // where the origin node is the intro node. We now fully disallow considering candidate hops
7198 // where the origin node is the intro node.
7199 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7200 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7201 let scorer = ln_test_utils::TestScorer::new();
7202 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7203 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7204 let config = UserConfig::default();
7206 // Values are taken from the fuzz input that uncovered this panic.
7207 let amt_msat = 21_7020_5185_1423_0019;
7209 let blinded_path = BlindedPath {
7210 introduction_node_id: our_id,
7211 blinding_point: ln_test_utils::pubkey(42),
7213 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7214 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7217 let blinded_payinfo = BlindedPayInfo {
7218 fee_base_msat: 5052_9027,
7219 fee_proportional_millionths: 0,
7220 htlc_minimum_msat: 21_7020_5185_1423_0019,
7221 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7222 cltv_expiry_delta: 0,
7223 features: BlindedHopFeatures::empty(),
7225 let mut blinded_hints = vec![
7226 (blinded_payinfo.clone(), blinded_path.clone()),
7227 (blinded_payinfo.clone(), blinded_path.clone()),
7229 blinded_hints[1].1.introduction_node_id = nodes[6];
7231 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7232 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7233 .with_bolt12_features(bolt12_features.clone()).unwrap();
7235 let netgraph = network_graph.read_only();
7236 let route_params = RouteParameters::from_payment_params_and_value(
7237 payment_params, amt_msat);
7238 if let Err(LightningError { err, .. }) = get_route(
7239 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7241 assert_eq!(err, "Failed to find a path to the given destination");
7246 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7247 // This previously led to a debug panic in the router because we'd find an invalid Path with
7248 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7249 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7250 // the payment, when it was intended to only include the final value of the payment.
7251 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7252 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7253 let scorer = ln_test_utils::TestScorer::new();
7254 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7255 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7256 let config = UserConfig::default();
7258 // Values are taken from the fuzz input that uncovered this panic.
7259 let amt_msat = 21_7020_5185_1423_0019;
7261 let blinded_path = BlindedPath {
7262 introduction_node_id: our_id,
7263 blinding_point: ln_test_utils::pubkey(42),
7265 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7266 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7269 let blinded_payinfo = BlindedPayInfo {
7270 fee_base_msat: 10_4425_1395,
7271 fee_proportional_millionths: 0,
7272 htlc_minimum_msat: 21_7301_9934_9094_0931,
7273 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7274 cltv_expiry_delta: 0,
7275 features: BlindedHopFeatures::empty(),
7277 let mut blinded_hints = vec![
7278 (blinded_payinfo.clone(), blinded_path.clone()),
7279 (blinded_payinfo.clone(), blinded_path.clone()),
7280 (blinded_payinfo.clone(), blinded_path.clone()),
7282 blinded_hints[1].0.fee_base_msat = 5052_9027;
7283 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7284 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7286 blinded_hints[2].1.introduction_node_id = nodes[6];
7288 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7289 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7290 .with_bolt12_features(bolt12_features.clone()).unwrap();
7292 let netgraph = network_graph.read_only();
7293 let route_params = RouteParameters::from_payment_params_and_value(
7294 payment_params, amt_msat);
7295 if let Err(LightningError { err, .. }) = get_route(
7296 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7298 assert_eq!(err, "Failed to find a path to the given destination");
7303 fn min_htlc_overpay_violates_max_htlc() {
7304 do_min_htlc_overpay_violates_max_htlc(true);
7305 do_min_htlc_overpay_violates_max_htlc(false);
7307 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7308 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7309 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7310 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7311 // that the used liquidity for a hop was less than its available liquidity limit.
7312 let secp_ctx = Secp256k1::new();
7313 let logger = Arc::new(ln_test_utils::TestLogger::new());
7314 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7315 let scorer = ln_test_utils::TestScorer::new();
7316 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7317 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7318 let config = UserConfig::default();
7320 // Values are taken from the fuzz input that uncovered this panic.
7321 let amt_msat = 7_4009_8048;
7322 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7323 let first_hop_outbound_capacity = 2_7345_2000;
7324 let first_hops = vec![get_channel_details(
7325 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7326 first_hop_outbound_capacity
7329 let base_fee = 1_6778_3453;
7330 let htlc_min = 2_5165_8240;
7331 let payment_params = if blinded_payee {
7332 let blinded_path = BlindedPath {
7333 introduction_node_id: nodes[0],
7334 blinding_point: ln_test_utils::pubkey(42),
7336 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7337 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7340 let blinded_payinfo = BlindedPayInfo {
7341 fee_base_msat: base_fee,
7342 fee_proportional_millionths: 0,
7343 htlc_minimum_msat: htlc_min,
7344 htlc_maximum_msat: htlc_min * 1000,
7345 cltv_expiry_delta: 0,
7346 features: BlindedHopFeatures::empty(),
7348 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7349 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7350 .with_bolt12_features(bolt12_features.clone()).unwrap()
7352 let route_hint = RouteHint(vec![RouteHintHop {
7353 src_node_id: nodes[0],
7354 short_channel_id: 42,
7356 base_msat: base_fee,
7357 proportional_millionths: 0,
7359 cltv_expiry_delta: 10,
7360 htlc_minimum_msat: Some(htlc_min),
7361 htlc_maximum_msat: None,
7364 PaymentParameters::from_node_id(nodes[1], 42)
7365 .with_route_hints(vec![route_hint]).unwrap()
7366 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7369 let netgraph = network_graph.read_only();
7370 let route_params = RouteParameters::from_payment_params_and_value(
7371 payment_params, amt_msat);
7372 if let Err(LightningError { err, .. }) = get_route(
7373 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7374 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7376 assert_eq!(err, "Failed to find a path to the given destination");
7381 fn previously_used_liquidity_violates_max_htlc() {
7382 do_previously_used_liquidity_violates_max_htlc(true);
7383 do_previously_used_liquidity_violates_max_htlc(false);
7386 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7387 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7388 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7389 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7390 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7391 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7392 let secp_ctx = Secp256k1::new();
7393 let logger = Arc::new(ln_test_utils::TestLogger::new());
7394 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7395 let scorer = ln_test_utils::TestScorer::new();
7396 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7397 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7398 let config = UserConfig::default();
7400 // Values are taken from the fuzz input that uncovered this panic.
7401 let amt_msat = 52_4288;
7402 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7403 let first_hops = vec![get_channel_details(
7404 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7405 ), get_channel_details(
7406 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7409 let base_fees = [0, 425_9840, 0, 0];
7410 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7411 let payment_params = if blinded_payee {
7412 let blinded_path = BlindedPath {
7413 introduction_node_id: nodes[0],
7414 blinding_point: ln_test_utils::pubkey(42),
7416 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7417 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7420 let mut blinded_hints = Vec::new();
7421 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7422 blinded_hints.push((BlindedPayInfo {
7423 fee_base_msat: *base_fee,
7424 fee_proportional_millionths: 0,
7425 htlc_minimum_msat: *htlc_min,
7426 htlc_maximum_msat: htlc_min * 100,
7427 cltv_expiry_delta: 10,
7428 features: BlindedHopFeatures::empty(),
7429 }, blinded_path.clone()));
7431 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7432 PaymentParameters::blinded(blinded_hints.clone())
7433 .with_bolt12_features(bolt12_features.clone()).unwrap()
7435 let mut route_hints = Vec::new();
7436 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7437 route_hints.push(RouteHint(vec![RouteHintHop {
7438 src_node_id: nodes[0],
7439 short_channel_id: 42 + idx as u64,
7441 base_msat: *base_fee,
7442 proportional_millionths: 0,
7444 cltv_expiry_delta: 10,
7445 htlc_minimum_msat: Some(*htlc_min),
7446 htlc_maximum_msat: Some(htlc_min * 100),
7449 PaymentParameters::from_node_id(nodes[1], 42)
7450 .with_route_hints(route_hints).unwrap()
7451 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7454 let netgraph = network_graph.read_only();
7455 let route_params = RouteParameters::from_payment_params_and_value(
7456 payment_params, amt_msat);
7458 let route = get_route(
7459 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7460 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7462 assert_eq!(route.paths.len(), 1);
7463 assert_eq!(route.get_total_amount(), amt_msat);
7467 fn candidate_path_min() {
7468 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7469 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7470 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7471 // would add a connecting first_hop node that did not have enough contribution amount, leading
7472 // to a debug panic upon invalid path construction.
7473 let secp_ctx = Secp256k1::new();
7474 let logger = Arc::new(ln_test_utils::TestLogger::new());
7475 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7476 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7477 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7478 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7479 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7480 let config = UserConfig::default();
7482 // Values are taken from the fuzz input that uncovered this panic.
7483 let amt_msat = 7_4009_8048;
7484 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7485 let first_hops = vec![get_channel_details(
7486 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7489 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7490 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7491 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7492 short_channel_id: 6,
7495 cltv_expiry_delta: (6 << 4) | 0,
7496 htlc_minimum_msat: 0,
7497 htlc_maximum_msat: MAX_VALUE_MSAT,
7499 fee_proportional_millionths: 0,
7500 excess_data: Vec::new()
7502 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7504 let htlc_min = 2_5165_8240;
7505 let blinded_hints = vec![
7507 fee_base_msat: 1_6778_3453,
7508 fee_proportional_millionths: 0,
7509 htlc_minimum_msat: htlc_min,
7510 htlc_maximum_msat: htlc_min * 100,
7511 cltv_expiry_delta: 10,
7512 features: BlindedHopFeatures::empty(),
7514 introduction_node_id: nodes[0],
7515 blinding_point: ln_test_utils::pubkey(42),
7517 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7518 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7522 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7523 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7524 .with_bolt12_features(bolt12_features.clone()).unwrap();
7525 let route_params = RouteParameters::from_payment_params_and_value(
7526 payment_params, amt_msat);
7527 let netgraph = network_graph.read_only();
7529 if let Err(LightningError { err, .. }) = get_route(
7530 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7531 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7534 assert_eq!(err, "Failed to find a path to the given destination");
7539 fn path_contribution_includes_min_htlc_overpay() {
7540 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7541 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7542 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7543 // selection, both tested here.
7544 let secp_ctx = Secp256k1::new();
7545 let logger = Arc::new(ln_test_utils::TestLogger::new());
7546 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7547 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7548 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7549 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7550 let config = UserConfig::default();
7552 // Values are taken from the fuzz input that uncovered this panic.
7553 let amt_msat = 562_0000;
7554 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7555 let first_hops = vec![
7556 get_channel_details(
7557 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7561 let htlc_mins = [49_0000, 1125_0000];
7562 let payment_params = {
7563 let blinded_path = BlindedPath {
7564 introduction_node_id: nodes[0],
7565 blinding_point: ln_test_utils::pubkey(42),
7567 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7568 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7571 let mut blinded_hints = Vec::new();
7572 for htlc_min in htlc_mins.iter() {
7573 blinded_hints.push((BlindedPayInfo {
7575 fee_proportional_millionths: 0,
7576 htlc_minimum_msat: *htlc_min,
7577 htlc_maximum_msat: *htlc_min * 100,
7578 cltv_expiry_delta: 10,
7579 features: BlindedHopFeatures::empty(),
7580 }, blinded_path.clone()));
7582 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7583 PaymentParameters::blinded(blinded_hints.clone())
7584 .with_bolt12_features(bolt12_features.clone()).unwrap()
7587 let netgraph = network_graph.read_only();
7588 let route_params = RouteParameters::from_payment_params_and_value(
7589 payment_params, amt_msat);
7590 let route = get_route(
7591 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7592 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7595 assert_eq!(route.paths.len(), 1);
7596 assert_eq!(route.get_total_amount(), amt_msat);
7600 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7601 pub(crate) mod bench_utils {
7605 use bitcoin::hashes::Hash;
7606 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7608 use crate::chain::transaction::OutPoint;
7609 use crate::routing::scoring::ScoreUpdate;
7610 use crate::sign::{EntropySource, KeysManager};
7611 use crate::ln::ChannelId;
7612 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7613 use crate::ln::features::Bolt11InvoiceFeatures;
7614 use crate::routing::gossip::NetworkGraph;
7615 use crate::util::config::UserConfig;
7616 use crate::util::ser::ReadableArgs;
7617 use crate::util::test_utils::TestLogger;
7619 /// Tries to open a network graph file, or panics with a URL to fetch it.
7620 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7621 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7622 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7623 .or_else(|_| { // Fall back to guessing based on the binary location
7624 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7625 let mut path = std::env::current_exe().unwrap();
7626 path.pop(); // lightning-...
7628 path.pop(); // debug
7629 path.pop(); // target
7630 path.push("lightning");
7631 path.push("net_graph-2023-01-18.bin");
7634 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7635 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7636 let mut path = std::env::current_exe().unwrap();
7637 path.pop(); // bench...
7639 path.pop(); // debug
7640 path.pop(); // target
7641 path.pop(); // bench
7642 path.push("lightning");
7643 path.push("net_graph-2023-01-18.bin");
7646 .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");
7647 #[cfg(require_route_graph_test)]
7648 return Ok(res.unwrap());
7649 #[cfg(not(require_route_graph_test))]
7653 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7654 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7657 pub(crate) fn payer_pubkey() -> PublicKey {
7658 let secp_ctx = Secp256k1::new();
7659 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7663 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7665 channel_id: ChannelId::new_zero(),
7666 counterparty: ChannelCounterparty {
7667 features: channelmanager::provided_init_features(&UserConfig::default()),
7669 unspendable_punishment_reserve: 0,
7670 forwarding_info: None,
7671 outbound_htlc_minimum_msat: None,
7672 outbound_htlc_maximum_msat: None,
7674 funding_txo: Some(OutPoint {
7675 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7678 short_channel_id: Some(1),
7679 inbound_scid_alias: None,
7680 outbound_scid_alias: None,
7681 channel_value_satoshis: 10_000_000_000,
7683 outbound_capacity_msat: 10_000_000_000,
7684 next_outbound_htlc_minimum_msat: 0,
7685 next_outbound_htlc_limit_msat: 10_000_000_000,
7686 inbound_capacity_msat: 0,
7687 unspendable_punishment_reserve: None,
7688 confirmations_required: None,
7689 confirmations: None,
7690 force_close_spend_delay: None,
7692 is_channel_ready: true,
7695 inbound_htlc_minimum_msat: None,
7696 inbound_htlc_maximum_msat: None,
7698 feerate_sat_per_1000_weight: None,
7699 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7703 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7704 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7705 starting_amount: u64, route_count: usize,
7706 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7707 let payer = payer_pubkey();
7708 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7709 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7711 let nodes = graph.read_only().nodes().clone();
7712 let mut route_endpoints = Vec::new();
7713 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7714 // with some routes we picked being un-routable.
7715 for _ in 0..route_count * 3 / 2 {
7717 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7718 let src = PublicKey::from_slice(nodes.unordered_keys()
7719 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7720 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7721 let dst = PublicKey::from_slice(nodes.unordered_keys()
7722 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7723 let params = PaymentParameters::from_node_id(dst, 42)
7724 .with_bolt11_features(features.clone()).unwrap();
7725 let first_hop = first_hop(src);
7726 let amt_msat = starting_amount + seed % 1_000_000;
7727 let route_params = RouteParameters::from_payment_params_and_value(
7728 params.clone(), amt_msat);
7730 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7731 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7733 // ...and seed the scorer with success and failure data...
7734 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7735 let mut score_amt = seed % 1_000_000_000;
7737 // Generate fail/success paths for a wider range of potential amounts with
7738 // MPP enabled to give us a chance to apply penalties for more potential
7740 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7741 let params = PaymentParameters::from_node_id(dst, 42)
7742 .with_bolt11_features(mpp_features).unwrap();
7743 let route_params = RouteParameters::from_payment_params_and_value(
7744 params.clone(), score_amt);
7745 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7746 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7747 &random_seed_bytes);
7748 if let Ok(route) = route_res {
7749 for path in route.paths {
7750 if seed & 0x80 == 0 {
7751 scorer.payment_path_successful(&path);
7753 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7754 scorer.payment_path_failed(&path, short_channel_id);
7756 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7760 // If we couldn't find a path with a higer amount, reduce and try again.
7764 route_endpoints.push((first_hop, params, amt_msat));
7770 // Because we've changed channel scores, it's possible we'll take different routes to the
7771 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7772 // requires a too-high CLTV delta.
7773 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7774 let route_params = RouteParameters::from_payment_params_and_value(
7775 params.clone(), *amt_msat);
7776 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7777 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7779 route_endpoints.truncate(route_count);
7780 assert_eq!(route_endpoints.len(), route_count);
7788 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7789 use crate::sign::{EntropySource, KeysManager};
7790 use crate::ln::channelmanager;
7791 use crate::ln::features::Bolt11InvoiceFeatures;
7792 use crate::routing::gossip::NetworkGraph;
7793 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7794 use crate::util::config::UserConfig;
7795 use crate::util::logger::{Logger, Record};
7796 use crate::util::test_utils::TestLogger;
7798 use criterion::Criterion;
7800 struct DummyLogger {}
7801 impl Logger for DummyLogger {
7802 fn log(&self, _record: &Record) {}
7805 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7806 let logger = TestLogger::new();
7807 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7808 let scorer = FixedPenaltyScorer::with_penalty(0);
7809 generate_routes(bench, &network_graph, scorer, &Default::default(),
7810 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
7813 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7814 let logger = TestLogger::new();
7815 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7816 let scorer = FixedPenaltyScorer::with_penalty(0);
7817 generate_routes(bench, &network_graph, scorer, &Default::default(),
7818 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7819 "generate_mpp_routes_with_zero_penalty_scorer");
7822 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7823 let logger = TestLogger::new();
7824 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7825 let params = ProbabilisticScoringFeeParameters::default();
7826 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7827 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7828 "generate_routes_with_probabilistic_scorer");
7831 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7832 let logger = TestLogger::new();
7833 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7834 let params = ProbabilisticScoringFeeParameters::default();
7835 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7836 generate_routes(bench, &network_graph, scorer, ¶ms,
7837 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7838 "generate_mpp_routes_with_probabilistic_scorer");
7841 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7842 let logger = TestLogger::new();
7843 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7844 let params = ProbabilisticScoringFeeParameters::default();
7845 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7846 generate_routes(bench, &network_graph, scorer, ¶ms,
7847 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7848 "generate_large_mpp_routes_with_probabilistic_scorer");
7851 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7852 let logger = TestLogger::new();
7853 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7854 let mut params = ProbabilisticScoringFeeParameters::default();
7855 params.linear_success_probability = false;
7856 let scorer = ProbabilisticScorer::new(
7857 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7858 generate_routes(bench, &network_graph, scorer, ¶ms,
7859 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7860 "generate_routes_with_nonlinear_probabilistic_scorer");
7863 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7864 let logger = TestLogger::new();
7865 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7866 let mut params = ProbabilisticScoringFeeParameters::default();
7867 params.linear_success_probability = false;
7868 let scorer = ProbabilisticScorer::new(
7869 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7870 generate_routes(bench, &network_graph, scorer, ¶ms,
7871 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7872 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
7875 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7876 let logger = TestLogger::new();
7877 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7878 let mut params = ProbabilisticScoringFeeParameters::default();
7879 params.linear_success_probability = false;
7880 let scorer = ProbabilisticScorer::new(
7881 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7882 generate_routes(bench, &network_graph, scorer, ¶ms,
7883 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7884 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
7887 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7888 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7889 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7890 bench_name: &'static str,
7892 let payer = bench_utils::payer_pubkey();
7893 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7894 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7896 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7897 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7899 // ...then benchmark finding paths between the nodes we learned.
7901 bench.bench_function(bench_name, |b| b.iter(|| {
7902 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
7903 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
7904 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7905 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());