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 let max_total_routing_fee_msat = route_params.max_total_routing_fee_msat.unwrap_or(u64::max_value());
1627 log_trace!(logger, "Searching for a route from payer {} to {} {} MPP and {} first hops {}overriding the network graph with a fee limit of {} msat",
1628 our_node_pubkey, LoggedPayeePubkey(payment_params.payee.node_id()),
1629 if allow_mpp { "with" } else { "without" },
1630 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " },
1631 max_total_routing_fee_msat);
1634 // Prepare the data we'll use for payee-to-payer search by
1635 // inserting first hops suggested by the caller as targets.
1636 // Our search will then attempt to reach them while traversing from the payee node.
1637 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1638 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1639 if let Some(hops) = first_hops {
1641 if chan.get_outbound_payment_scid().is_none() {
1642 panic!("first_hops should be filled in with usable channels, not pending ones");
1644 if chan.counterparty.node_id == *our_node_pubkey {
1645 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1648 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1649 .or_insert(Vec::new())
1652 if first_hop_targets.is_empty() {
1653 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1657 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1658 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1659 // adding duplicate entries when we find a better path to a given node.
1660 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1662 // Map from node_id to information about the best current path to that node, including feerate
1664 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1666 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1667 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1668 // htlc_minimum with extra fees while still finding a cheaper path.
1669 let mut hit_minimum_limit;
1671 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1672 // We start with a path_value of the exact amount we want, and if that generates a route we may
1673 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1674 // amount we want in total across paths, selecting the best subset at the end.
1675 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1676 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1677 let mut path_value_msat = final_value_msat;
1679 // Routing Fragmentation Mitigation heuristic:
1681 // Routing fragmentation across many payment paths increases the overall routing
1682 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1683 // Taking too many smaller paths also increases the chance of payment failure.
1684 // Thus to avoid this effect, we require from our collected links to provide
1685 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1686 // This requirement is currently set to be 1/max_path_count of the payment
1687 // value to ensure we only ever return routes that do not violate this limit.
1688 let minimal_value_contribution_msat: u64 = if allow_mpp {
1689 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1694 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1695 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1696 // drop the requirement by setting this to 0.
1697 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1699 // Keep track of how much liquidity has been used in selected channels or blinded paths. Used to
1700 // determine if the channel can be used by additional MPP paths or to inform path finding
1701 // decisions. It is aware of direction *only* to ensure that the correct htlc_maximum_msat value
1702 // is used. Hence, liquidity used in one direction will not offset any used in the opposite
1704 let mut used_liquidities: HashMap<CandidateHopId, u64> =
1705 HashMap::with_capacity(network_nodes.len());
1707 // Keeping track of how much value we already collected across other paths. Helps to decide
1708 // when we want to stop looking for new paths.
1709 let mut already_collected_value_msat = 0;
1711 for (_, channels) in first_hop_targets.iter_mut() {
1712 sort_first_hop_channels(channels, &used_liquidities, recommended_value_msat,
1716 log_trace!(logger, "Building path from {} to payer {} for value {} msat.",
1717 LoggedPayeePubkey(payment_params.payee.node_id()), our_node_pubkey, final_value_msat);
1719 // Remember how many candidates we ignored to allow for some logging afterwards.
1720 let mut num_ignored_value_contribution: u32 = 0;
1721 let mut num_ignored_path_length_limit: u32 = 0;
1722 let mut num_ignored_cltv_delta_limit: u32 = 0;
1723 let mut num_ignored_previously_failed: u32 = 0;
1724 let mut num_ignored_total_fee_limit: u32 = 0;
1725 let mut num_ignored_avoid_overpayment: u32 = 0;
1726 let mut num_ignored_htlc_minimum_msat_limit: u32 = 0;
1728 macro_rules! add_entry {
1729 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1730 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1731 // since that value has to be transferred over this channel.
1732 // Returns the contribution amount of $candidate if the channel caused an update to `targets`.
1733 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1734 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1735 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1736 // We "return" whether we updated the path at the end, and how much we can route via
1737 // this channel, via this:
1738 let mut hop_contribution_amt_msat = None;
1739 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1740 // practice these cases should be caught earlier:
1741 // - for regular channels at channel announcement (TODO)
1742 // - for first and last hops early in get_route
1743 if $src_node_id != $dest_node_id {
1744 let scid_opt = $candidate.short_channel_id();
1745 let effective_capacity = $candidate.effective_capacity();
1746 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1748 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1749 // It may be misleading because we might later choose to reduce the value transferred
1750 // over these channels, and the channel which was insufficient might become sufficient.
1751 // Worst case: we drop a good channel here because it can't cover the high following
1752 // fees caused by one expensive channel, but then this channel could have been used
1753 // if the amount being transferred over this path is lower.
1754 // We do this for now, but this is a subject for removal.
1755 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1756 let used_liquidity_msat = used_liquidities
1757 .get(&$candidate.id($src_node_id < $dest_node_id))
1758 .map_or(0, |used_liquidity_msat| {
1759 available_value_contribution_msat = available_value_contribution_msat
1760 .saturating_sub(*used_liquidity_msat);
1761 *used_liquidity_msat
1764 // Verify the liquidity offered by this channel complies to the minimal contribution.
1765 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1766 // Do not consider candidate hops that would exceed the maximum path length.
1767 let path_length_to_node = $next_hops_path_length + 1;
1768 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1770 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1771 // In order to already account for some of the privacy enhancing random CLTV
1772 // expiry delta offset we add on top later, we subtract a rough estimate
1773 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1774 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1775 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1776 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1777 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1778 .saturating_add($candidate.cltv_expiry_delta());
1779 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1781 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1782 // Includes paying fees for the use of the following channels.
1783 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1784 Some(result) => result,
1785 // Can't overflow due to how the values were computed right above.
1786 None => unreachable!(),
1788 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1789 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1790 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1792 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1793 let may_overpay_to_meet_path_minimum_msat =
1794 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1795 recommended_value_msat >= $candidate.htlc_minimum_msat()) ||
1796 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1797 recommended_value_msat >= $next_hops_path_htlc_minimum_msat));
1799 let payment_failed_on_this_channel = scid_opt.map_or(false,
1800 |scid| payment_params.previously_failed_channels.contains(&scid));
1802 let should_log_candidate = match $candidate {
1803 CandidateRouteHop::FirstHop { .. } => true,
1804 CandidateRouteHop::PrivateHop { .. } => true,
1805 CandidateRouteHop::Blinded { .. } => true,
1806 CandidateRouteHop::OneHopBlinded { .. } => true,
1810 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1811 // bother considering this channel. If retrying with recommended_value_msat may
1812 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1813 // around again with a higher amount.
1814 if !contributes_sufficient_value {
1815 if should_log_candidate {
1816 log_trace!(logger, "Ignoring {} due to insufficient value contribution.", LoggedCandidateHop(&$candidate));
1818 num_ignored_value_contribution += 1;
1819 } else if exceeds_max_path_length {
1820 if should_log_candidate {
1821 log_trace!(logger, "Ignoring {} due to exceeding maximum path length limit.", LoggedCandidateHop(&$candidate));
1823 num_ignored_path_length_limit += 1;
1824 } else if exceeds_cltv_delta_limit {
1825 if should_log_candidate {
1826 log_trace!(logger, "Ignoring {} due to exceeding CLTV delta limit.", LoggedCandidateHop(&$candidate));
1828 num_ignored_cltv_delta_limit += 1;
1829 } else if payment_failed_on_this_channel {
1830 if should_log_candidate {
1831 log_trace!(logger, "Ignoring {} due to a failed previous payment attempt.", LoggedCandidateHop(&$candidate));
1833 num_ignored_previously_failed += 1;
1834 } else if may_overpay_to_meet_path_minimum_msat {
1835 if should_log_candidate {
1837 "Ignoring {} to avoid overpaying to meet htlc_minimum_msat limit.",
1838 LoggedCandidateHop(&$candidate));
1840 num_ignored_avoid_overpayment += 1;
1841 hit_minimum_limit = true;
1842 } else if over_path_minimum_msat {
1843 // Note that low contribution here (limited by available_liquidity_msat)
1844 // might violate htlc_minimum_msat on the hops which are next along the
1845 // payment path (upstream to the payee). To avoid that, we recompute
1846 // path fees knowing the final path contribution after constructing it.
1847 let curr_min = cmp::max(
1848 $next_hops_path_htlc_minimum_msat, $candidate.htlc_minimum_msat()
1850 let path_htlc_minimum_msat = compute_fees_saturating(curr_min, $candidate.fees())
1851 .saturating_add(curr_min);
1852 let hm_entry = dist.entry($src_node_id);
1853 let old_entry = hm_entry.or_insert_with(|| {
1854 // If there was previously no known way to access the source node
1855 // (recall it goes payee-to-payer) of short_channel_id, first add a
1856 // semi-dummy record just to compute the fees to reach the source node.
1857 // This will affect our decision on selecting short_channel_id
1858 // as a way to reach the $dest_node_id.
1860 node_id: $dest_node_id.clone(),
1861 candidate: $candidate.clone(),
1863 next_hops_fee_msat: u64::max_value(),
1864 hop_use_fee_msat: u64::max_value(),
1865 total_fee_msat: u64::max_value(),
1866 path_htlc_minimum_msat,
1867 path_penalty_msat: u64::max_value(),
1868 was_processed: false,
1869 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1870 value_contribution_msat,
1874 #[allow(unused_mut)] // We only use the mut in cfg(test)
1875 let mut should_process = !old_entry.was_processed;
1876 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1878 // In test/fuzzing builds, we do extra checks to make sure the skipping
1879 // of already-seen nodes only happens in cases we expect (see below).
1880 if !should_process { should_process = true; }
1884 let mut hop_use_fee_msat = 0;
1885 let mut total_fee_msat: u64 = $next_hops_fee_msat;
1887 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1888 // will have the same effective-fee
1889 if $src_node_id != our_node_id {
1890 // Note that `u64::max_value` means we'll always fail the
1891 // `old_entry.total_fee_msat > total_fee_msat` check below
1892 hop_use_fee_msat = compute_fees_saturating(amount_to_transfer_over_msat, $candidate.fees());
1893 total_fee_msat = total_fee_msat.saturating_add(hop_use_fee_msat);
1896 // Ignore hops if augmenting the current path to them would put us over `max_total_routing_fee_msat`
1897 if total_fee_msat > max_total_routing_fee_msat {
1898 if should_log_candidate {
1899 log_trace!(logger, "Ignoring {} due to exceeding max total routing fee limit.", LoggedCandidateHop(&$candidate));
1901 num_ignored_total_fee_limit += 1;
1903 let channel_usage = ChannelUsage {
1904 amount_msat: amount_to_transfer_over_msat,
1905 inflight_htlc_msat: used_liquidity_msat,
1908 let channel_penalty_msat = scid_opt.map_or(0,
1909 |scid| scorer.channel_penalty_msat(scid, &$src_node_id, &$dest_node_id,
1910 channel_usage, score_params));
1911 let path_penalty_msat = $next_hops_path_penalty_msat
1912 .saturating_add(channel_penalty_msat);
1913 let new_graph_node = RouteGraphNode {
1914 node_id: $src_node_id,
1915 lowest_fee_to_node: total_fee_msat,
1916 total_cltv_delta: hop_total_cltv_delta,
1917 value_contribution_msat,
1918 path_htlc_minimum_msat,
1920 path_length_to_node,
1923 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1924 // if this way is cheaper than the already known
1925 // (considering the cost to "reach" this channel from the route destination,
1926 // the cost of using this channel,
1927 // and the cost of routing to the source node of this channel).
1928 // Also, consider that htlc_minimum_msat_difference, because we might end up
1929 // paying it. Consider the following exploit:
1930 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1931 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1932 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1933 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1935 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1936 // but it may require additional tracking - we don't want to double-count
1937 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1938 // can't use something that may decrease on future hops.
1939 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1940 .saturating_add(old_entry.path_penalty_msat);
1941 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1942 .saturating_add(path_penalty_msat);
1944 if !old_entry.was_processed && new_cost < old_cost {
1945 targets.push(new_graph_node);
1946 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1947 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1948 old_entry.total_fee_msat = total_fee_msat;
1949 old_entry.node_id = $dest_node_id.clone();
1950 old_entry.candidate = $candidate.clone();
1951 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1952 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1953 old_entry.path_penalty_msat = path_penalty_msat;
1954 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1956 old_entry.value_contribution_msat = value_contribution_msat;
1958 hop_contribution_amt_msat = Some(value_contribution_msat);
1959 } else if old_entry.was_processed && new_cost < old_cost {
1960 #[cfg(all(not(ldk_bench), any(test, fuzzing)))]
1962 // If we're skipping processing a node which was previously
1963 // processed even though we found another path to it with a
1964 // cheaper fee, check that it was because the second path we
1965 // found (which we are processing now) has a lower value
1966 // contribution due to an HTLC minimum limit.
1968 // e.g. take a graph with two paths from node 1 to node 2, one
1969 // through channel A, and one through channel B. Channel A and
1970 // B are both in the to-process heap, with their scores set by
1971 // a higher htlc_minimum than fee.
1972 // Channel A is processed first, and the channels onwards from
1973 // node 1 are added to the to-process heap. Thereafter, we pop
1974 // Channel B off of the heap, note that it has a much more
1975 // restrictive htlc_maximum_msat, and recalculate the fees for
1976 // all of node 1's channels using the new, reduced, amount.
1978 // This would be bogus - we'd be selecting a higher-fee path
1979 // with a lower htlc_maximum_msat instead of the one we'd
1980 // already decided to use.
1981 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1983 value_contribution_msat + path_penalty_msat <
1984 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1991 if should_log_candidate {
1993 "Ignoring {} due to its htlc_minimum_msat limit.",
1994 LoggedCandidateHop(&$candidate));
1996 num_ignored_htlc_minimum_msat_limit += 1;
2000 hop_contribution_amt_msat
2004 let default_node_features = default_node_features();
2006 // Find ways (channels with destination) to reach a given node and store them
2007 // in the corresponding data structures (routing graph etc).
2008 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
2009 // meaning how much will be paid in fees after this node (to the best of our knowledge).
2010 // This data can later be helpful to optimize routing (pay lower fees).
2011 macro_rules! add_entries_to_cheapest_to_target_node {
2012 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
2013 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
2014 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
2015 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
2016 let was_processed = elem.was_processed;
2017 elem.was_processed = true;
2020 // Entries are added to dist in add_entry!() when there is a channel from a node.
2021 // Because there are no channels from payee, it will not have a dist entry at this point.
2022 // If we're processing any other node, it is always be the result of a channel from it.
2023 debug_assert_eq!($node_id, maybe_dummy_payee_node_id);
2028 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
2029 for details in first_channels {
2030 let candidate = CandidateRouteHop::FirstHop { details };
2031 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
2032 $next_hops_value_contribution,
2033 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
2034 $next_hops_cltv_delta, $next_hops_path_length);
2038 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
2041 &default_node_features
2044 if !features.requires_unknown_bits() {
2045 for chan_id in $node.channels.iter() {
2046 let chan = network_channels.get(chan_id).unwrap();
2047 if !chan.features.requires_unknown_bits() {
2048 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
2049 if first_hops.is_none() || *source != our_node_id {
2050 if directed_channel.direction().enabled {
2051 let candidate = CandidateRouteHop::PublicHop {
2052 info: directed_channel,
2053 short_channel_id: *chan_id,
2055 add_entry!(candidate, *source, $node_id,
2056 $fee_to_target_msat,
2057 $next_hops_value_contribution,
2058 $next_hops_path_htlc_minimum_msat,
2059 $next_hops_path_penalty_msat,
2060 $next_hops_cltv_delta, $next_hops_path_length);
2071 let mut payment_paths = Vec::<PaymentPath>::new();
2073 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
2074 'paths_collection: loop {
2075 // For every new path, start from scratch, except for used_liquidities, which
2076 // helps to avoid reusing previously selected paths in future iterations.
2079 hit_minimum_limit = false;
2081 // If first hop is a private channel and the only way to reach the payee, this is the only
2082 // place where it could be added.
2083 payee_node_id_opt.map(|payee| first_hop_targets.get(&payee).map(|first_channels| {
2084 for details in first_channels {
2085 let candidate = CandidateRouteHop::FirstHop { details };
2086 let added = add_entry!(candidate, our_node_id, payee, 0, path_value_msat,
2087 0, 0u64, 0, 0).is_some();
2088 log_trace!(logger, "{} direct route to payee via {}",
2089 if added { "Added" } else { "Skipped" }, LoggedCandidateHop(&candidate));
2093 // Add the payee as a target, so that the payee-to-payer
2094 // search algorithm knows what to start with.
2095 payee_node_id_opt.map(|payee| match network_nodes.get(&payee) {
2096 // The payee is not in our network graph, so nothing to add here.
2097 // There is still a chance of reaching them via last_hops though,
2098 // so don't yet fail the payment here.
2099 // If not, targets.pop() will not even let us enter the loop in step 2.
2102 add_entries_to_cheapest_to_target_node!(node, payee, 0, path_value_msat, 0, 0u64, 0, 0);
2107 // If a caller provided us with last hops, add them to routing targets. Since this happens
2108 // earlier than general path finding, they will be somewhat prioritized, although currently
2109 // it matters only if the fees are exactly the same.
2110 for (hint_idx, hint) in payment_params.payee.blinded_route_hints().iter().enumerate() {
2111 let intro_node_id = NodeId::from_pubkey(&hint.1.introduction_node_id);
2112 let have_intro_node_in_graph =
2113 // Only add the hops in this route to our candidate set if either
2114 // we have a direct channel to the first hop or the first hop is
2115 // in the regular network graph.
2116 first_hop_targets.get(&intro_node_id).is_some() ||
2117 network_nodes.get(&intro_node_id).is_some();
2118 if !have_intro_node_in_graph || our_node_id == intro_node_id { continue }
2119 let candidate = if hint.1.blinded_hops.len() == 1 {
2120 CandidateRouteHop::OneHopBlinded { hint, hint_idx }
2121 } else { CandidateRouteHop::Blinded { hint, hint_idx } };
2122 let mut path_contribution_msat = path_value_msat;
2123 if let Some(hop_used_msat) = add_entry!(candidate, intro_node_id, maybe_dummy_payee_node_id,
2124 0, path_contribution_msat, 0, 0_u64, 0, 0)
2126 path_contribution_msat = hop_used_msat;
2128 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hint.1.introduction_node_id)) {
2129 sort_first_hop_channels(first_channels, &used_liquidities, recommended_value_msat,
2131 for details in first_channels {
2132 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2133 let blinded_path_fee = match compute_fees(path_contribution_msat, candidate.fees()) {
2137 let path_min = candidate.htlc_minimum_msat().saturating_add(
2138 compute_fees_saturating(candidate.htlc_minimum_msat(), candidate.fees()));
2139 add_entry!(first_hop_candidate, our_node_id, intro_node_id, blinded_path_fee,
2140 path_contribution_msat, path_min, 0_u64, candidate.cltv_expiry_delta(),
2141 candidate.blinded_path().map_or(1, |bp| bp.blinded_hops.len() as u8));
2145 for route in payment_params.payee.unblinded_route_hints().iter()
2146 .filter(|route| !route.0.is_empty())
2148 let first_hop_src_id = NodeId::from_pubkey(&route.0.first().unwrap().src_node_id);
2149 let first_hop_src_is_reachable =
2150 // Only add the hops in this route to our candidate set if either we are part of
2151 // the first hop, we have a direct channel to the first hop, or the first hop is in
2152 // the regular network graph.
2153 our_node_id == first_hop_src_id ||
2154 first_hop_targets.get(&first_hop_src_id).is_some() ||
2155 network_nodes.get(&first_hop_src_id).is_some();
2156 if first_hop_src_is_reachable {
2157 // We start building the path from reverse, i.e., from payee
2158 // to the first RouteHintHop in the path.
2159 let hop_iter = route.0.iter().rev();
2160 let prev_hop_iter = core::iter::once(&maybe_dummy_payee_pk).chain(
2161 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
2162 let mut hop_used = true;
2163 let mut aggregate_next_hops_fee_msat: u64 = 0;
2164 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
2165 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
2166 let mut aggregate_next_hops_cltv_delta: u32 = 0;
2167 let mut aggregate_next_hops_path_length: u8 = 0;
2168 let mut aggregate_path_contribution_msat = path_value_msat;
2170 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
2171 let source = NodeId::from_pubkey(&hop.src_node_id);
2172 let target = NodeId::from_pubkey(&prev_hop_id);
2174 if let Some(first_channels) = first_hop_targets.get(&target) {
2175 if first_channels.iter().any(|d| d.outbound_scid_alias == Some(hop.short_channel_id)) {
2176 log_trace!(logger, "Ignoring route hint with SCID {} (and any previous) due to it being a direct channel of ours.",
2177 hop.short_channel_id);
2182 let candidate = network_channels
2183 .get(&hop.short_channel_id)
2184 .and_then(|channel| channel.as_directed_to(&target))
2185 .map(|(info, _)| CandidateRouteHop::PublicHop {
2187 short_channel_id: hop.short_channel_id,
2189 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
2191 if let Some(hop_used_msat) = add_entry!(candidate, source, target,
2192 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2193 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2194 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length)
2196 aggregate_path_contribution_msat = hop_used_msat;
2198 // If this hop was not used then there is no use checking the preceding
2199 // hops in the RouteHint. We can break by just searching for a direct
2200 // channel between last checked hop and first_hop_targets.
2204 let used_liquidity_msat = used_liquidities
2205 .get(&candidate.id(source < target)).copied()
2207 let channel_usage = ChannelUsage {
2208 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
2209 inflight_htlc_msat: used_liquidity_msat,
2210 effective_capacity: candidate.effective_capacity(),
2212 let channel_penalty_msat = scorer.channel_penalty_msat(
2213 hop.short_channel_id, &source, &target, channel_usage, score_params
2215 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
2216 .saturating_add(channel_penalty_msat);
2218 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
2219 .saturating_add(hop.cltv_expiry_delta as u32);
2221 aggregate_next_hops_path_length = aggregate_next_hops_path_length
2224 // Searching for a direct channel between last checked hop and first_hop_targets
2225 if let Some(first_channels) = first_hop_targets.get_mut(&target) {
2226 sort_first_hop_channels(first_channels, &used_liquidities,
2227 recommended_value_msat, our_node_pubkey);
2228 for details in first_channels {
2229 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2230 add_entry!(first_hop_candidate, our_node_id, target,
2231 aggregate_next_hops_fee_msat, aggregate_path_contribution_msat,
2232 aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat,
2233 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length);
2241 // In the next values of the iterator, the aggregate fees already reflects
2242 // the sum of value sent from payer (final_value_msat) and routing fees
2243 // for the last node in the RouteHint. We need to just add the fees to
2244 // route through the current node so that the preceding node (next iteration)
2246 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
2247 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
2248 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
2250 // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
2251 // this route hint's source node to forward said min over this channel.
2252 aggregate_next_hops_path_htlc_minimum_msat = {
2253 let curr_htlc_min = cmp::max(
2254 candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
2256 let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
2257 if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
2260 if idx == route.0.len() - 1 {
2261 // The last hop in this iterator is the first hop in
2262 // overall RouteHint.
2263 // If this hop connects to a node with which we have a direct channel,
2264 // ignore the network graph and, if the last hop was added, add our
2265 // direct channel to the candidate set.
2267 // Note that we *must* check if the last hop was added as `add_entry`
2268 // always assumes that the third argument is a node to which we have a
2270 if let Some(first_channels) = first_hop_targets.get_mut(&NodeId::from_pubkey(&hop.src_node_id)) {
2271 sort_first_hop_channels(first_channels, &used_liquidities,
2272 recommended_value_msat, our_node_pubkey);
2273 for details in first_channels {
2274 let first_hop_candidate = CandidateRouteHop::FirstHop { details };
2275 add_entry!(first_hop_candidate, our_node_id,
2276 NodeId::from_pubkey(&hop.src_node_id),
2277 aggregate_next_hops_fee_msat,
2278 aggregate_path_contribution_msat,
2279 aggregate_next_hops_path_htlc_minimum_msat,
2280 aggregate_next_hops_path_penalty_msat,
2281 aggregate_next_hops_cltv_delta,
2282 aggregate_next_hops_path_length);
2290 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
2292 // At this point, targets are filled with the data from first and
2293 // last hops communicated by the caller, and the payment receiver.
2294 let mut found_new_path = false;
2297 // If this loop terminates due the exhaustion of targets, two situations are possible:
2298 // - not enough outgoing liquidity:
2299 // 0 < already_collected_value_msat < final_value_msat
2300 // - enough outgoing liquidity:
2301 // final_value_msat <= already_collected_value_msat < recommended_value_msat
2302 // Both these cases (and other cases except reaching recommended_value_msat) mean that
2303 // paths_collection will be stopped because found_new_path==false.
2304 // This is not necessarily a routing failure.
2305 '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() {
2307 // Since we're going payee-to-payer, hitting our node as a target means we should stop
2308 // traversing the graph and arrange the path out of what we found.
2309 if node_id == our_node_id {
2310 let mut new_entry = dist.remove(&our_node_id).unwrap();
2311 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
2314 let mut features_set = false;
2315 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
2316 for details in first_channels {
2317 if let Some(scid) = ordered_hops.last().unwrap().0.candidate.short_channel_id() {
2318 if details.get_outbound_payment_scid().unwrap() == scid {
2319 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
2320 features_set = true;
2327 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
2328 if let Some(node_info) = node.announcement_info.as_ref() {
2329 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
2331 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
2334 // We can fill in features for everything except hops which were
2335 // provided via the invoice we're paying. We could guess based on the
2336 // recipient's features but for now we simply avoid guessing at all.
2340 // Means we succesfully traversed from the payer to the payee, now
2341 // save this path for the payment route. Also, update the liquidity
2342 // remaining on the used hops, so that we take them into account
2343 // while looking for more paths.
2344 if ordered_hops.last().unwrap().0.node_id == maybe_dummy_payee_node_id {
2348 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
2349 Some(payment_hop) => payment_hop,
2350 // We can't arrive at None because, if we ever add an entry to targets,
2351 // we also fill in the entry in dist (see add_entry!).
2352 None => unreachable!(),
2354 // We "propagate" the fees one hop backward (topologically) here,
2355 // so that fees paid for a HTLC forwarding on the current channel are
2356 // associated with the previous channel (where they will be subtracted).
2357 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
2358 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
2360 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
2361 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
2363 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
2364 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
2366 let mut payment_path = PaymentPath {hops: ordered_hops};
2368 // We could have possibly constructed a slightly inconsistent path: since we reduce
2369 // value being transferred along the way, we could have violated htlc_minimum_msat
2370 // on some channels we already passed (assuming dest->source direction). Here, we
2371 // recompute the fees again, so that if that's the case, we match the currently
2372 // underpaid htlc_minimum_msat with fees.
2373 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
2374 let desired_value_contribution = cmp::min(value_contribution_msat, final_value_msat);
2375 value_contribution_msat = payment_path.update_value_and_recompute_fees(desired_value_contribution);
2377 // Since a path allows to transfer as much value as
2378 // the smallest channel it has ("bottleneck"), we should recompute
2379 // the fees so sender HTLC don't overpay fees when traversing
2380 // larger channels than the bottleneck. This may happen because
2381 // when we were selecting those channels we were not aware how much value
2382 // this path will transfer, and the relative fee for them
2383 // might have been computed considering a larger value.
2384 // Remember that we used these channels so that we don't rely
2385 // on the same liquidity in future paths.
2386 let mut prevented_redundant_path_selection = false;
2387 let prev_hop_iter = core::iter::once(&our_node_id)
2388 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
2389 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
2390 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
2391 let used_liquidity_msat = used_liquidities
2392 .entry(hop.candidate.id(*prev_hop < hop.node_id))
2393 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
2394 .or_insert(spent_on_hop_msat);
2395 let hop_capacity = hop.candidate.effective_capacity();
2396 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
2397 if *used_liquidity_msat == hop_max_msat {
2398 // If this path used all of this channel's available liquidity, we know
2399 // this path will not be selected again in the next loop iteration.
2400 prevented_redundant_path_selection = true;
2402 debug_assert!(*used_liquidity_msat <= hop_max_msat);
2404 if !prevented_redundant_path_selection {
2405 // If we weren't capped by hitting a liquidity limit on a channel in the path,
2406 // we'll probably end up picking the same path again on the next iteration.
2407 // Decrease the available liquidity of a hop in the middle of the path.
2408 let victim_candidate = &payment_path.hops[(payment_path.hops.len()) / 2].0.candidate;
2409 let exhausted = u64::max_value();
2411 "Disabling route candidate {} for future path building iterations to avoid duplicates.",
2412 LoggedCandidateHop(victim_candidate));
2413 *used_liquidities.entry(victim_candidate.id(false)).or_default() = exhausted;
2414 *used_liquidities.entry(victim_candidate.id(true)).or_default() = exhausted;
2417 // Track the total amount all our collected paths allow to send so that we know
2418 // when to stop looking for more paths
2419 already_collected_value_msat += value_contribution_msat;
2421 payment_paths.push(payment_path);
2422 found_new_path = true;
2423 break 'path_construction;
2426 // If we found a path back to the payee, we shouldn't try to process it again. This is
2427 // the equivalent of the `elem.was_processed` check in
2428 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
2429 if node_id == maybe_dummy_payee_node_id { continue 'path_construction; }
2431 // Otherwise, since the current target node is not us,
2432 // keep "unrolling" the payment graph from payee to payer by
2433 // finding a way to reach the current target from the payer side.
2434 match network_nodes.get(&node_id) {
2437 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
2438 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
2439 total_cltv_delta, path_length_to_node);
2445 if !found_new_path && channel_saturation_pow_half != 0 {
2446 channel_saturation_pow_half = 0;
2447 continue 'paths_collection;
2449 // If we don't support MPP, no use trying to gather more value ever.
2450 break 'paths_collection;
2454 // Stop either when the recommended value is reached or if no new path was found in this
2456 // In the latter case, making another path finding attempt won't help,
2457 // because we deterministically terminated the search due to low liquidity.
2458 if !found_new_path && channel_saturation_pow_half != 0 {
2459 channel_saturation_pow_half = 0;
2460 } else if !found_new_path && hit_minimum_limit && already_collected_value_msat < final_value_msat && path_value_msat != recommended_value_msat {
2461 log_trace!(logger, "Failed to collect enough value, but running again to collect extra paths with a potentially higher limit.");
2462 path_value_msat = recommended_value_msat;
2463 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
2464 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
2465 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
2466 break 'paths_collection;
2467 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
2468 // Further, if this was our first walk of the graph, and we weren't limited by an
2469 // htlc_minimum_msat, return immediately because this path should suffice. If we were
2470 // limited by an htlc_minimum_msat value, find another path with a higher value,
2471 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
2472 // still keeping a lower total fee than this path.
2473 if !hit_minimum_limit {
2474 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
2475 break 'paths_collection;
2477 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher value to meet htlc_minimum_msat limit.");
2478 path_value_msat = recommended_value_msat;
2482 let num_ignored_total = num_ignored_value_contribution + num_ignored_path_length_limit +
2483 num_ignored_cltv_delta_limit + num_ignored_previously_failed +
2484 num_ignored_avoid_overpayment + num_ignored_htlc_minimum_msat_limit +
2485 num_ignored_total_fee_limit;
2486 if num_ignored_total > 0 {
2488 "Ignored {} candidate hops due to insufficient value contribution, {} due to path length limit, {} due to CLTV delta limit, {} due to previous payment failure, {} due to htlc_minimum_msat limit, {} to avoid overpaying, {} due to maximum total fee limit. Total: {} ignored candidates.",
2489 num_ignored_value_contribution, num_ignored_path_length_limit,
2490 num_ignored_cltv_delta_limit, num_ignored_previously_failed,
2491 num_ignored_htlc_minimum_msat_limit, num_ignored_avoid_overpayment,
2492 num_ignored_total_fee_limit, num_ignored_total);
2496 if payment_paths.len() == 0 {
2497 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2500 if already_collected_value_msat < final_value_msat {
2501 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
2505 let mut selected_route = payment_paths;
2507 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
2508 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
2510 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
2511 // the value they contribute towards the payment amount.
2512 // We sort in descending order as we will remove from the front in `retain`, next.
2513 selected_route.sort_unstable_by(|a, b|
2514 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
2515 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
2518 // We should make sure that at least 1 path left.
2519 let mut paths_left = selected_route.len();
2520 selected_route.retain(|path| {
2521 if paths_left == 1 {
2524 let path_value_msat = path.get_value_msat();
2525 if path_value_msat <= overpaid_value_msat {
2526 overpaid_value_msat -= path_value_msat;
2532 debug_assert!(selected_route.len() > 0);
2534 if overpaid_value_msat != 0 {
2536 // Now, subtract the remaining overpaid value from the most-expensive path.
2537 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
2538 // so that the sender pays less fees overall. And also htlc_minimum_msat.
2539 selected_route.sort_unstable_by(|a, b| {
2540 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2541 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
2542 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
2544 let expensive_payment_path = selected_route.first_mut().unwrap();
2546 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
2547 // can't go negative.
2548 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
2549 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
2553 // Sort by the path itself and combine redundant paths.
2554 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
2555 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
2557 selected_route.sort_unstable_by_key(|path| {
2558 let mut key = [CandidateHopId::Clear((42, true)) ; MAX_PATH_LENGTH_ESTIMATE as usize];
2559 debug_assert!(path.hops.len() <= key.len());
2560 for (scid, key) in path.hops.iter() .map(|h| h.0.candidate.id(true)).zip(key.iter_mut()) {
2565 for idx in 0..(selected_route.len() - 1) {
2566 if idx + 1 >= selected_route.len() { break; }
2567 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id)),
2568 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.id(true), h.0.node_id))) {
2569 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
2570 selected_route[idx].update_value_and_recompute_fees(new_value);
2571 selected_route.remove(idx + 1);
2575 let mut paths = Vec::new();
2576 for payment_path in selected_route {
2577 let mut hops = Vec::with_capacity(payment_path.hops.len());
2578 let mut prev_hop_node_id = our_node_id;
2579 for (hop, node_features) in payment_path.hops.iter()
2580 .filter(|(h, _)| h.candidate.short_channel_id().is_some())
2582 let maybe_announced_channel = if let CandidateRouteHop::PublicHop { .. } = hop.candidate {
2583 // If we sourced the hop from the graph we're sure the target node is announced.
2585 } else if let CandidateRouteHop::FirstHop { details } = hop.candidate {
2586 // If this is a first hop we also know if it's announced.
2589 // If we sourced it any other way, we double-check the network graph to see if
2590 // there are announced channels between the endpoints. If so, the hop might be
2591 // referring to any of the announced channels, as its `short_channel_id` might be
2592 // an alias, in which case we don't take any chances here.
2593 network_graph.node(&hop.node_id).map_or(false, |hop_node|
2594 hop_node.channels.iter().any(|scid| network_graph.channel(*scid)
2595 .map_or(false, |c| c.as_directed_from(&prev_hop_node_id).is_some()))
2599 hops.push(RouteHop {
2600 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)})?,
2601 node_features: node_features.clone(),
2602 short_channel_id: hop.candidate.short_channel_id().unwrap(),
2603 channel_features: hop.candidate.features(),
2604 fee_msat: hop.fee_msat,
2605 cltv_expiry_delta: hop.candidate.cltv_expiry_delta(),
2606 maybe_announced_channel,
2609 prev_hop_node_id = hop.node_id;
2611 let mut final_cltv_delta = final_cltv_expiry_delta;
2612 let blinded_tail = payment_path.hops.last().and_then(|(h, _)| {
2613 if let Some(blinded_path) = h.candidate.blinded_path() {
2614 final_cltv_delta = h.candidate.cltv_expiry_delta();
2616 hops: blinded_path.blinded_hops.clone(),
2617 blinding_point: blinded_path.blinding_point,
2618 excess_final_cltv_expiry_delta: 0,
2619 final_value_msat: h.fee_msat,
2623 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
2624 // applicable for the previous hop.
2625 hops.iter_mut().rev().fold(final_cltv_delta, |prev_cltv_expiry_delta, hop| {
2626 core::mem::replace(&mut hop.cltv_expiry_delta, prev_cltv_expiry_delta)
2629 paths.push(Path { hops, blinded_tail });
2631 // Make sure we would never create a route with more paths than we allow.
2632 debug_assert!(paths.len() <= payment_params.max_path_count.into());
2634 if let Some(node_features) = payment_params.payee.node_features() {
2635 for path in paths.iter_mut() {
2636 path.hops.last_mut().unwrap().node_features = node_features.clone();
2640 let route = Route { paths, route_params: Some(route_params.clone()) };
2642 // Make sure we would never create a route whose total fees exceed max_total_routing_fee_msat.
2643 if let Some(max_total_routing_fee_msat) = route_params.max_total_routing_fee_msat {
2644 if route.get_total_fees() > max_total_routing_fee_msat {
2645 return Err(LightningError{err: format!("Failed to find route that adheres to the maximum total fee limit of {}msat",
2646 max_total_routing_fee_msat), action: ErrorAction::IgnoreError});
2650 log_info!(logger, "Got route: {}", log_route!(route));
2654 // When an adversarial intermediary node observes a payment, it may be able to infer its
2655 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
2656 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
2657 // payment path by adding a randomized 'shadow route' offset to the final hop.
2658 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
2659 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
2661 let network_channels = network_graph.channels();
2662 let network_nodes = network_graph.nodes();
2664 for path in route.paths.iter_mut() {
2665 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
2667 // Remember the last three nodes of the random walk and avoid looping back on them.
2668 // Init with the last three nodes from the actual path, if possible.
2669 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.hops.last().unwrap().pubkey),
2670 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(2)).unwrap().pubkey),
2671 NodeId::from_pubkey(&path.hops.get(path.hops.len().saturating_sub(3)).unwrap().pubkey)];
2673 // Choose the last publicly known node as the starting point for the random walk.
2674 let mut cur_hop: Option<NodeId> = None;
2675 let mut path_nonce = [0u8; 12];
2676 if let Some(starting_hop) = path.hops.iter().rev()
2677 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
2678 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
2679 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
2682 // Init PRNG with the path-dependant nonce, which is static for private paths.
2683 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
2684 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2686 // Pick a random path length in [1 .. 3]
2687 prng.process_in_place(&mut random_path_bytes);
2688 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2690 for random_hop in 0..random_walk_length {
2691 // If we don't find a suitable offset in the public network graph, we default to
2692 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2693 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2695 if let Some(cur_node_id) = cur_hop {
2696 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2697 // Randomly choose the next unvisited hop.
2698 prng.process_in_place(&mut random_path_bytes);
2699 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2700 .checked_rem(cur_node.channels.len())
2701 .and_then(|index| cur_node.channels.get(index))
2702 .and_then(|id| network_channels.get(id)) {
2703 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2704 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2705 nodes_to_avoid[random_hop] = *next_id;
2706 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2707 cur_hop = Some(*next_id);
2714 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2715 .checked_add(random_hop_offset)
2716 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2719 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2720 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2721 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2723 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2724 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2725 let path_total_cltv_expiry_delta: u32 = path.hops.iter().map(|h| h.cltv_expiry_delta).sum();
2726 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2727 max_path_offset = cmp::max(
2728 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2729 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2730 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2732 // Add 'shadow' CLTV offset to the final hop
2733 if let Some(tail) = path.blinded_tail.as_mut() {
2734 tail.excess_final_cltv_expiry_delta = tail.excess_final_cltv_expiry_delta
2735 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(tail.excess_final_cltv_expiry_delta);
2737 if let Some(last_hop) = path.hops.last_mut() {
2738 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2739 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2744 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2745 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2747 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2748 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2749 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2750 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2751 ) -> Result<Route, LightningError>
2752 where L::Target: Logger, GL::Target: Logger {
2753 let graph_lock = network_graph.read_only();
2754 let mut route = build_route_from_hops_internal(our_node_pubkey, hops, &route_params,
2755 &graph_lock, logger, random_seed_bytes)?;
2756 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2760 fn build_route_from_hops_internal<L: Deref>(
2761 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2762 network_graph: &ReadOnlyNetworkGraph, logger: L, random_seed_bytes: &[u8; 32],
2763 ) -> Result<Route, LightningError> where L::Target: Logger {
2766 our_node_id: NodeId,
2767 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2770 impl ScoreLookUp for HopScorer {
2771 type ScoreParams = ();
2772 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2773 _usage: ChannelUsage, _score_params: &Self::ScoreParams) -> u64
2775 let mut cur_id = self.our_node_id;
2776 for i in 0..self.hop_ids.len() {
2777 if let Some(next_id) = self.hop_ids[i] {
2778 if cur_id == *source && next_id == *target {
2790 impl<'a> Writeable for HopScorer {
2792 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2797 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2798 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2801 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2802 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2803 for i in 0..hops.len() {
2804 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2807 let scorer = HopScorer { our_node_id, hop_ids };
2809 get_route(our_node_pubkey, route_params, network_graph, None, logger, &scorer, &Default::default(), random_seed_bytes)
2814 use crate::blinded_path::{BlindedHop, BlindedPath};
2815 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2816 use crate::routing::utxo::UtxoResult;
2817 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2818 BlindedTail, InFlightHtlcs, Path, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2819 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE, RouteParameters};
2820 use crate::routing::scoring::{ChannelUsage, FixedPenaltyScorer, ScoreLookUp, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
2821 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2822 use crate::chain::transaction::OutPoint;
2823 use crate::sign::EntropySource;
2824 use crate::ln::ChannelId;
2825 use crate::ln::features::{BlindedHopFeatures, Bolt12InvoiceFeatures, ChannelFeatures, InitFeatures, NodeFeatures};
2826 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2827 use crate::ln::channelmanager;
2828 use crate::offers::invoice::BlindedPayInfo;
2829 use crate::util::config::UserConfig;
2830 use crate::util::test_utils as ln_test_utils;
2831 use crate::util::chacha20::ChaCha20;
2832 use crate::util::ser::{Readable, Writeable};
2834 use crate::util::ser::Writer;
2836 use bitcoin::hashes::Hash;
2837 use bitcoin::network::constants::Network;
2838 use bitcoin::blockdata::constants::genesis_block;
2839 use bitcoin::blockdata::script::Builder;
2840 use bitcoin::blockdata::opcodes;
2841 use bitcoin::blockdata::transaction::TxOut;
2845 use bitcoin::secp256k1::{PublicKey,SecretKey};
2846 use bitcoin::secp256k1::Secp256k1;
2848 use crate::io::Cursor;
2849 use crate::prelude::*;
2850 use crate::sync::Arc;
2852 use core::convert::TryInto;
2854 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2855 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2856 channelmanager::ChannelDetails {
2857 channel_id: ChannelId::new_zero(),
2858 counterparty: channelmanager::ChannelCounterparty {
2861 unspendable_punishment_reserve: 0,
2862 forwarding_info: None,
2863 outbound_htlc_minimum_msat: None,
2864 outbound_htlc_maximum_msat: None,
2866 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2869 outbound_scid_alias: None,
2870 inbound_scid_alias: None,
2871 channel_value_satoshis: 0,
2873 outbound_capacity_msat,
2874 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2875 next_outbound_htlc_minimum_msat: 0,
2876 inbound_capacity_msat: 42,
2877 unspendable_punishment_reserve: None,
2878 confirmations_required: None,
2879 confirmations: None,
2880 force_close_spend_delay: None,
2881 is_outbound: true, is_channel_ready: true,
2882 is_usable: true, is_public: true,
2883 inbound_htlc_minimum_msat: None,
2884 inbound_htlc_maximum_msat: None,
2886 feerate_sat_per_1000_weight: None,
2887 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
2892 fn simple_route_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 route_params = RouteParameters::from_payment_params_and_value(
2903 payment_params.clone(), 0);
2904 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2905 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
2906 &Default::default(), &random_seed_bytes) {
2907 assert_eq!(err, "Cannot send a payment of 0 msat");
2908 } else { panic!(); }
2910 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
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);
2915 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
2916 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
2917 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
2918 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
2919 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
2920 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
2922 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
2923 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
2924 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
2925 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
2926 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
2927 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
2931 fn invalid_first_hop_test() {
2932 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2933 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2934 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2935 let scorer = ln_test_utils::TestScorer::new();
2936 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2937 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2939 // Simple route to 2 via 1
2941 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2943 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
2944 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
2945 &route_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()),
2946 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
2947 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2948 } else { panic!(); }
2950 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
2951 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
2952 assert_eq!(route.paths[0].hops.len(), 2);
2956 fn htlc_minimum_test() {
2957 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2958 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2959 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
2960 let scorer = ln_test_utils::TestScorer::new();
2961 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2962 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2964 // Simple route to 2 via 1
2966 // Disable other paths
2967 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2968 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2969 short_channel_id: 12,
2971 flags: 2, // to disable
2972 cltv_expiry_delta: 0,
2973 htlc_minimum_msat: 0,
2974 htlc_maximum_msat: MAX_VALUE_MSAT,
2976 fee_proportional_millionths: 0,
2977 excess_data: Vec::new()
2979 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2980 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2981 short_channel_id: 3,
2983 flags: 2, // to disable
2984 cltv_expiry_delta: 0,
2985 htlc_minimum_msat: 0,
2986 htlc_maximum_msat: MAX_VALUE_MSAT,
2988 fee_proportional_millionths: 0,
2989 excess_data: Vec::new()
2991 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2992 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2993 short_channel_id: 13,
2995 flags: 2, // to disable
2996 cltv_expiry_delta: 0,
2997 htlc_minimum_msat: 0,
2998 htlc_maximum_msat: MAX_VALUE_MSAT,
3000 fee_proportional_millionths: 0,
3001 excess_data: Vec::new()
3003 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3004 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3005 short_channel_id: 6,
3007 flags: 2, // to disable
3008 cltv_expiry_delta: 0,
3009 htlc_minimum_msat: 0,
3010 htlc_maximum_msat: MAX_VALUE_MSAT,
3012 fee_proportional_millionths: 0,
3013 excess_data: Vec::new()
3015 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3016 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3017 short_channel_id: 7,
3019 flags: 2, // to disable
3020 cltv_expiry_delta: 0,
3021 htlc_minimum_msat: 0,
3022 htlc_maximum_msat: MAX_VALUE_MSAT,
3024 fee_proportional_millionths: 0,
3025 excess_data: Vec::new()
3028 // Check against amount_to_transfer_over_msat.
3029 // Set minimal HTLC of 200_000_000 msat.
3030 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3031 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3032 short_channel_id: 2,
3035 cltv_expiry_delta: 0,
3036 htlc_minimum_msat: 200_000_000,
3037 htlc_maximum_msat: MAX_VALUE_MSAT,
3039 fee_proportional_millionths: 0,
3040 excess_data: Vec::new()
3043 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
3045 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3046 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3047 short_channel_id: 4,
3050 cltv_expiry_delta: 0,
3051 htlc_minimum_msat: 0,
3052 htlc_maximum_msat: 199_999_999,
3054 fee_proportional_millionths: 0,
3055 excess_data: Vec::new()
3058 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
3059 let route_params = RouteParameters::from_payment_params_and_value(
3060 payment_params, 199_999_999);
3061 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3062 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3063 &Default::default(), &random_seed_bytes) {
3064 assert_eq!(err, "Failed to find a path to the given destination");
3065 } else { panic!(); }
3067 // Lift the restriction on the first hop.
3068 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3069 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3070 short_channel_id: 2,
3073 cltv_expiry_delta: 0,
3074 htlc_minimum_msat: 0,
3075 htlc_maximum_msat: MAX_VALUE_MSAT,
3077 fee_proportional_millionths: 0,
3078 excess_data: Vec::new()
3081 // A payment above the minimum should pass
3082 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3083 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3084 assert_eq!(route.paths[0].hops.len(), 2);
3088 fn htlc_minimum_overpay_test() {
3089 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3090 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3091 let config = UserConfig::default();
3092 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3093 let scorer = ln_test_utils::TestScorer::new();
3094 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3095 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3097 // A route to node#2 via two paths.
3098 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
3099 // Thus, they can't send 60 without overpaying.
3100 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3101 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3102 short_channel_id: 2,
3105 cltv_expiry_delta: 0,
3106 htlc_minimum_msat: 35_000,
3107 htlc_maximum_msat: 40_000,
3109 fee_proportional_millionths: 0,
3110 excess_data: Vec::new()
3112 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3113 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3114 short_channel_id: 12,
3117 cltv_expiry_delta: 0,
3118 htlc_minimum_msat: 35_000,
3119 htlc_maximum_msat: 40_000,
3121 fee_proportional_millionths: 0,
3122 excess_data: Vec::new()
3126 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3127 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3128 short_channel_id: 13,
3131 cltv_expiry_delta: 0,
3132 htlc_minimum_msat: 0,
3133 htlc_maximum_msat: MAX_VALUE_MSAT,
3135 fee_proportional_millionths: 0,
3136 excess_data: Vec::new()
3138 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3139 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3140 short_channel_id: 4,
3143 cltv_expiry_delta: 0,
3144 htlc_minimum_msat: 0,
3145 htlc_maximum_msat: MAX_VALUE_MSAT,
3147 fee_proportional_millionths: 0,
3148 excess_data: Vec::new()
3151 // Disable other paths
3152 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3153 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3154 short_channel_id: 1,
3156 flags: 2, // to disable
3157 cltv_expiry_delta: 0,
3158 htlc_minimum_msat: 0,
3159 htlc_maximum_msat: MAX_VALUE_MSAT,
3161 fee_proportional_millionths: 0,
3162 excess_data: Vec::new()
3165 let mut route_params = RouteParameters::from_payment_params_and_value(
3166 payment_params.clone(), 60_000);
3167 route_params.max_total_routing_fee_msat = Some(15_000);
3168 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3169 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3170 // Overpay fees to hit htlc_minimum_msat.
3171 let overpaid_fees = route.paths[0].hops[0].fee_msat + route.paths[1].hops[0].fee_msat;
3172 // TODO: this could be better balanced to overpay 10k and not 15k.
3173 assert_eq!(overpaid_fees, 15_000);
3175 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
3176 // while taking even more fee to match htlc_minimum_msat.
3177 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3178 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3179 short_channel_id: 12,
3182 cltv_expiry_delta: 0,
3183 htlc_minimum_msat: 65_000,
3184 htlc_maximum_msat: 80_000,
3186 fee_proportional_millionths: 0,
3187 excess_data: Vec::new()
3189 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3190 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3191 short_channel_id: 2,
3194 cltv_expiry_delta: 0,
3195 htlc_minimum_msat: 0,
3196 htlc_maximum_msat: MAX_VALUE_MSAT,
3198 fee_proportional_millionths: 0,
3199 excess_data: Vec::new()
3201 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3202 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3203 short_channel_id: 4,
3206 cltv_expiry_delta: 0,
3207 htlc_minimum_msat: 0,
3208 htlc_maximum_msat: MAX_VALUE_MSAT,
3210 fee_proportional_millionths: 100_000,
3211 excess_data: Vec::new()
3214 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3215 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3216 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
3217 assert_eq!(route.paths.len(), 1);
3218 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
3219 let fees = route.paths[0].hops[0].fee_msat;
3220 assert_eq!(fees, 5_000);
3222 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 50_000);
3223 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3224 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3225 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
3226 // the other channel.
3227 assert_eq!(route.paths.len(), 1);
3228 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3229 let fees = route.paths[0].hops[0].fee_msat;
3230 assert_eq!(fees, 5_000);
3234 fn htlc_minimum_recipient_overpay_test() {
3235 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3236 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3237 let config = UserConfig::default();
3238 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
3239 let scorer = ln_test_utils::TestScorer::new();
3240 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3241 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3243 // Route to node2 over a single path which requires overpaying the recipient themselves.
3245 // First disable all paths except the us -> node1 -> node2 path
3246 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3247 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3248 short_channel_id: 13,
3251 cltv_expiry_delta: 0,
3252 htlc_minimum_msat: 0,
3253 htlc_maximum_msat: 0,
3255 fee_proportional_millionths: 0,
3256 excess_data: Vec::new()
3259 // Set channel 4 to free but with a high htlc_minimum_msat
3260 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3261 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3262 short_channel_id: 4,
3265 cltv_expiry_delta: 0,
3266 htlc_minimum_msat: 15_000,
3267 htlc_maximum_msat: MAX_VALUE_MSAT,
3269 fee_proportional_millionths: 0,
3270 excess_data: Vec::new()
3273 // Now check that we'll fail to find a path if we fail to find a path if the htlc_minimum
3274 // is overrun. Note that the fees are actually calculated on 3*payment amount as that's
3275 // what we try to find a route for, so this test only just happens to work out to exactly
3277 let mut route_params = RouteParameters::from_payment_params_and_value(
3278 payment_params.clone(), 5_000);
3279 route_params.max_total_routing_fee_msat = Some(9_999);
3280 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3281 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3282 &Default::default(), &random_seed_bytes) {
3283 assert_eq!(err, "Failed to find route that adheres to the maximum total fee limit of 9999msat");
3284 } else { panic!(); }
3286 let mut route_params = RouteParameters::from_payment_params_and_value(
3287 payment_params.clone(), 5_000);
3288 route_params.max_total_routing_fee_msat = Some(10_000);
3289 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3290 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3291 assert_eq!(route.get_total_fees(), 10_000);
3295 fn disable_channels_test() {
3296 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3297 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3298 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3299 let scorer = ln_test_utils::TestScorer::new();
3300 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3301 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3303 // // Disable channels 4 and 12 by flags=2
3304 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3306 short_channel_id: 4,
3308 flags: 2, // to disable
3309 cltv_expiry_delta: 0,
3310 htlc_minimum_msat: 0,
3311 htlc_maximum_msat: MAX_VALUE_MSAT,
3313 fee_proportional_millionths: 0,
3314 excess_data: Vec::new()
3316 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3317 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3318 short_channel_id: 12,
3320 flags: 2, // to disable
3321 cltv_expiry_delta: 0,
3322 htlc_minimum_msat: 0,
3323 htlc_maximum_msat: MAX_VALUE_MSAT,
3325 fee_proportional_millionths: 0,
3326 excess_data: Vec::new()
3329 // If all the channels require some features we don't understand, route should fail
3330 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3331 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3332 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3333 &Default::default(), &random_seed_bytes) {
3334 assert_eq!(err, "Failed to find a path to the given destination");
3335 } else { panic!(); }
3337 // If we specify a channel to node7, that overrides our local channel view and that gets used
3338 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3339 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3340 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3341 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3342 &Default::default(), &random_seed_bytes).unwrap();
3343 assert_eq!(route.paths[0].hops.len(), 2);
3345 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3346 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3347 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3348 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3349 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3350 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3352 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3353 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3354 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3355 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3356 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3357 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3361 fn disable_node_test() {
3362 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3363 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3364 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3365 let scorer = ln_test_utils::TestScorer::new();
3366 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3367 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3369 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
3370 let mut unknown_features = NodeFeatures::empty();
3371 unknown_features.set_unknown_feature_required();
3372 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
3373 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
3374 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
3376 // If all nodes require some features we don't understand, route should fail
3377 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3378 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3379 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3380 &Default::default(), &random_seed_bytes) {
3381 assert_eq!(err, "Failed to find a path to the given destination");
3382 } else { panic!(); }
3384 // If we specify a channel to node7, that overrides our local channel view and that gets used
3385 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3386 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3387 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3388 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3389 &Default::default(), &random_seed_bytes).unwrap();
3390 assert_eq!(route.paths[0].hops.len(), 2);
3392 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3393 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3394 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3395 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3396 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
3397 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3399 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3400 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3401 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3402 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3403 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3404 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3406 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
3407 // naively) assume that the user checked the feature bits on the invoice, which override
3408 // the node_announcement.
3412 fn our_chans_test() {
3413 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3414 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3415 let scorer = ln_test_utils::TestScorer::new();
3416 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3417 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3419 // Route to 1 via 2 and 3 because our channel to 1 is disabled
3420 let payment_params = PaymentParameters::from_node_id(nodes[0], 42);
3421 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3422 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3423 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3424 assert_eq!(route.paths[0].hops.len(), 3);
3426 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3427 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3428 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3429 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3430 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3431 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3433 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3434 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3435 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3436 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (3 << 4) | 2);
3437 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3438 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3440 assert_eq!(route.paths[0].hops[2].pubkey, nodes[0]);
3441 assert_eq!(route.paths[0].hops[2].short_channel_id, 3);
3442 assert_eq!(route.paths[0].hops[2].fee_msat, 100);
3443 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
3444 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(1));
3445 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(3));
3447 // If we specify a channel to node7, that overrides our local channel view and that gets used
3448 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
3449 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3450 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(),
3451 InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3452 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3453 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3454 &Default::default(), &random_seed_bytes).unwrap();
3455 assert_eq!(route.paths[0].hops.len(), 2);
3457 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
3458 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3459 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3460 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
3461 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3462 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3464 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3465 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
3466 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3467 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
3468 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3469 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
3472 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3473 let zero_fees = RoutingFees {
3475 proportional_millionths: 0,
3477 vec![RouteHint(vec![RouteHintHop {
3478 src_node_id: nodes[3],
3479 short_channel_id: 8,
3481 cltv_expiry_delta: (8 << 4) | 1,
3482 htlc_minimum_msat: None,
3483 htlc_maximum_msat: None,
3485 ]), RouteHint(vec![RouteHintHop {
3486 src_node_id: nodes[4],
3487 short_channel_id: 9,
3490 proportional_millionths: 0,
3492 cltv_expiry_delta: (9 << 4) | 1,
3493 htlc_minimum_msat: None,
3494 htlc_maximum_msat: None,
3495 }]), RouteHint(vec![RouteHintHop {
3496 src_node_id: nodes[5],
3497 short_channel_id: 10,
3499 cltv_expiry_delta: (10 << 4) | 1,
3500 htlc_minimum_msat: None,
3501 htlc_maximum_msat: None,
3505 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3506 let zero_fees = RoutingFees {
3508 proportional_millionths: 0,
3510 vec![RouteHint(vec![RouteHintHop {
3511 src_node_id: nodes[2],
3512 short_channel_id: 5,
3515 proportional_millionths: 0,
3517 cltv_expiry_delta: (5 << 4) | 1,
3518 htlc_minimum_msat: None,
3519 htlc_maximum_msat: None,
3521 src_node_id: nodes[3],
3522 short_channel_id: 8,
3524 cltv_expiry_delta: (8 << 4) | 1,
3525 htlc_minimum_msat: None,
3526 htlc_maximum_msat: None,
3528 ]), RouteHint(vec![RouteHintHop {
3529 src_node_id: nodes[4],
3530 short_channel_id: 9,
3533 proportional_millionths: 0,
3535 cltv_expiry_delta: (9 << 4) | 1,
3536 htlc_minimum_msat: None,
3537 htlc_maximum_msat: None,
3538 }]), RouteHint(vec![RouteHintHop {
3539 src_node_id: nodes[5],
3540 short_channel_id: 10,
3542 cltv_expiry_delta: (10 << 4) | 1,
3543 htlc_minimum_msat: None,
3544 htlc_maximum_msat: None,
3549 fn partial_route_hint_test() {
3550 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3551 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3552 let scorer = ln_test_utils::TestScorer::new();
3553 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3554 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3556 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3557 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3558 // RouteHint may be partially used by the algo to build the best path.
3560 // First check that last hop can't have its source as the payee.
3561 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3562 src_node_id: nodes[6],
3563 short_channel_id: 8,
3566 proportional_millionths: 0,
3568 cltv_expiry_delta: (8 << 4) | 1,
3569 htlc_minimum_msat: None,
3570 htlc_maximum_msat: None,
3573 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3574 invalid_last_hops.push(invalid_last_hop);
3576 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3577 .with_route_hints(invalid_last_hops).unwrap();
3578 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3579 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
3580 &route_params, &network_graph.read_only(), None, Arc::clone(&logger), &scorer,
3581 &Default::default(), &random_seed_bytes) {
3582 assert_eq!(err, "Route hint cannot have the payee as the source.");
3583 } else { panic!(); }
3586 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3587 .with_route_hints(last_hops_multi_private_channels(&nodes)).unwrap();
3588 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3589 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3590 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3591 assert_eq!(route.paths[0].hops.len(), 5);
3593 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3594 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3595 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3596 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3597 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3598 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3600 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3601 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3602 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3603 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3604 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3605 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3607 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3608 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3609 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3610 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3611 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3612 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3614 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3615 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3616 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3617 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3618 // If we have a peer in the node map, we'll use their features here since we don't have
3619 // a way of figuring out their features from the invoice:
3620 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3621 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3623 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3624 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3625 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3626 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3627 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3628 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3631 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3632 let zero_fees = RoutingFees {
3634 proportional_millionths: 0,
3636 vec![RouteHint(vec![RouteHintHop {
3637 src_node_id: nodes[3],
3638 short_channel_id: 8,
3640 cltv_expiry_delta: (8 << 4) | 1,
3641 htlc_minimum_msat: None,
3642 htlc_maximum_msat: None,
3643 }]), RouteHint(vec![
3645 ]), RouteHint(vec![RouteHintHop {
3646 src_node_id: nodes[5],
3647 short_channel_id: 10,
3649 cltv_expiry_delta: (10 << 4) | 1,
3650 htlc_minimum_msat: None,
3651 htlc_maximum_msat: None,
3656 fn ignores_empty_last_hops_test() {
3657 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3658 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3659 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(empty_last_hop(&nodes)).unwrap();
3660 let scorer = ln_test_utils::TestScorer::new();
3661 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3662 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3664 // Test handling of an empty RouteHint passed in Invoice.
3665 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3666 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3667 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3668 assert_eq!(route.paths[0].hops.len(), 5);
3670 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3671 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3672 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3673 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3674 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3675 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3677 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3678 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3679 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3680 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3681 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3682 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3684 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3685 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3686 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3687 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3688 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3689 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3691 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3692 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3693 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3694 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3695 // If we have a peer in the node map, we'll use their features here since we don't have
3696 // a way of figuring out their features from the invoice:
3697 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3698 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3700 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3701 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3702 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3703 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3704 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3705 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3708 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3710 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3711 let zero_fees = RoutingFees {
3713 proportional_millionths: 0,
3715 vec![RouteHint(vec![RouteHintHop {
3716 src_node_id: hint_hops[0],
3717 short_channel_id: 0xff00,
3720 proportional_millionths: 0,
3722 cltv_expiry_delta: (5 << 4) | 1,
3723 htlc_minimum_msat: None,
3724 htlc_maximum_msat: None,
3726 src_node_id: hint_hops[1],
3727 short_channel_id: 0xff01,
3729 cltv_expiry_delta: (8 << 4) | 1,
3730 htlc_minimum_msat: None,
3731 htlc_maximum_msat: None,
3736 fn multi_hint_last_hops_test() {
3737 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3738 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3739 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3740 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3741 let scorer = ln_test_utils::TestScorer::new();
3742 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3743 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3744 // Test through channels 2, 3, 0xff00, 0xff01.
3745 // Test shows that multiple hop hints are considered.
3747 // Disabling channels 6 & 7 by flags=2
3748 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3749 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3750 short_channel_id: 6,
3752 flags: 2, // to disable
3753 cltv_expiry_delta: 0,
3754 htlc_minimum_msat: 0,
3755 htlc_maximum_msat: MAX_VALUE_MSAT,
3757 fee_proportional_millionths: 0,
3758 excess_data: Vec::new()
3760 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3761 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3762 short_channel_id: 7,
3764 flags: 2, // to disable
3765 cltv_expiry_delta: 0,
3766 htlc_minimum_msat: 0,
3767 htlc_maximum_msat: MAX_VALUE_MSAT,
3769 fee_proportional_millionths: 0,
3770 excess_data: Vec::new()
3773 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3774 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3775 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3776 assert_eq!(route.paths[0].hops.len(), 4);
3778 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3779 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3780 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3781 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3782 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3783 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3785 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3786 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3787 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3788 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3789 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3790 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3792 assert_eq!(route.paths[0].hops[2].pubkey, nodes[3]);
3793 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3794 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3795 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3796 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(4));
3797 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3799 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3800 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3801 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3802 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3803 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3804 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3808 fn private_multi_hint_last_hops_test() {
3809 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3810 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3812 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3813 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3815 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3816 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops.clone()).unwrap();
3817 let scorer = ln_test_utils::TestScorer::new();
3818 // Test through channels 2, 3, 0xff00, 0xff01.
3819 // Test shows that multiple hop hints are considered.
3821 // Disabling channels 6 & 7 by flags=2
3822 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3824 short_channel_id: 6,
3826 flags: 2, // to disable
3827 cltv_expiry_delta: 0,
3828 htlc_minimum_msat: 0,
3829 htlc_maximum_msat: MAX_VALUE_MSAT,
3831 fee_proportional_millionths: 0,
3832 excess_data: Vec::new()
3834 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3836 short_channel_id: 7,
3838 flags: 2, // to disable
3839 cltv_expiry_delta: 0,
3840 htlc_minimum_msat: 0,
3841 htlc_maximum_msat: MAX_VALUE_MSAT,
3843 fee_proportional_millionths: 0,
3844 excess_data: Vec::new()
3847 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3848 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3849 Arc::clone(&logger), &scorer, &Default::default(), &[42u8; 32]).unwrap();
3850 assert_eq!(route.paths[0].hops.len(), 4);
3852 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3853 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3854 assert_eq!(route.paths[0].hops[0].fee_msat, 200);
3855 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, 65);
3856 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3857 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3859 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3860 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3861 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
3862 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 81);
3863 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3864 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3866 assert_eq!(route.paths[0].hops[2].pubkey, non_announced_pubkey);
3867 assert_eq!(route.paths[0].hops[2].short_channel_id, last_hops[0].0[0].short_channel_id);
3868 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3869 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 129);
3870 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3871 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3873 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
3874 assert_eq!(route.paths[0].hops[3].short_channel_id, last_hops[0].0[1].short_channel_id);
3875 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
3876 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
3877 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3878 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3881 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3882 let zero_fees = RoutingFees {
3884 proportional_millionths: 0,
3886 vec![RouteHint(vec![RouteHintHop {
3887 src_node_id: nodes[4],
3888 short_channel_id: 11,
3890 cltv_expiry_delta: (11 << 4) | 1,
3891 htlc_minimum_msat: None,
3892 htlc_maximum_msat: None,
3894 src_node_id: nodes[3],
3895 short_channel_id: 8,
3897 cltv_expiry_delta: (8 << 4) | 1,
3898 htlc_minimum_msat: None,
3899 htlc_maximum_msat: None,
3900 }]), RouteHint(vec![RouteHintHop {
3901 src_node_id: nodes[4],
3902 short_channel_id: 9,
3905 proportional_millionths: 0,
3907 cltv_expiry_delta: (9 << 4) | 1,
3908 htlc_minimum_msat: None,
3909 htlc_maximum_msat: None,
3910 }]), RouteHint(vec![RouteHintHop {
3911 src_node_id: nodes[5],
3912 short_channel_id: 10,
3914 cltv_expiry_delta: (10 << 4) | 1,
3915 htlc_minimum_msat: None,
3916 htlc_maximum_msat: None,
3921 fn last_hops_with_public_channel_test() {
3922 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3923 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3924 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops_with_public_channel(&nodes)).unwrap();
3925 let scorer = ln_test_utils::TestScorer::new();
3926 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3927 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3928 // This test shows that public routes can be present in the invoice
3929 // which would be handled in the same manner.
3931 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3932 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
3933 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
3934 assert_eq!(route.paths[0].hops.len(), 5);
3936 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
3937 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
3938 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
3939 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
3940 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
3941 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
3943 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
3944 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
3945 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
3946 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
3947 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
3948 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
3950 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
3951 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
3952 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
3953 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
3954 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
3955 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
3957 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
3958 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
3959 assert_eq!(route.paths[0].hops[3].fee_msat, 0);
3960 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
3961 // If we have a peer in the node map, we'll use their features here since we don't have
3962 // a way of figuring out their features from the invoice:
3963 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
3964 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
3966 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
3967 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
3968 assert_eq!(route.paths[0].hops[4].fee_msat, 100);
3969 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
3970 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3971 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3975 fn our_chans_last_hop_connect_test() {
3976 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3977 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3978 let scorer = ln_test_utils::TestScorer::new();
3979 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3980 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3982 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3983 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3984 let mut last_hops = last_hops(&nodes);
3985 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
3986 .with_route_hints(last_hops.clone()).unwrap();
3987 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
3988 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
3989 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
3990 &Default::default(), &random_seed_bytes).unwrap();
3991 assert_eq!(route.paths[0].hops.len(), 2);
3993 assert_eq!(route.paths[0].hops[0].pubkey, nodes[3]);
3994 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
3995 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
3996 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
3997 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &vec![0b11]);
3998 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
4000 assert_eq!(route.paths[0].hops[1].pubkey, nodes[6]);
4001 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4002 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4003 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4004 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4005 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4007 last_hops[0].0[0].fees.base_msat = 1000;
4009 // Revert to via 6 as the fee on 8 goes up
4010 let payment_params = PaymentParameters::from_node_id(nodes[6], 42)
4011 .with_route_hints(last_hops).unwrap();
4012 let route_params = RouteParameters::from_payment_params_and_value(
4013 payment_params.clone(), 100);
4014 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4015 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4016 assert_eq!(route.paths[0].hops.len(), 4);
4018 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4019 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4020 assert_eq!(route.paths[0].hops[0].fee_msat, 200); // fee increased as its % of value transferred across node
4021 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4022 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4023 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4025 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4026 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4027 assert_eq!(route.paths[0].hops[1].fee_msat, 100);
4028 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (7 << 4) | 1);
4029 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4030 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4032 assert_eq!(route.paths[0].hops[2].pubkey, nodes[5]);
4033 assert_eq!(route.paths[0].hops[2].short_channel_id, 7);
4034 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4035 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (10 << 4) | 1);
4036 // If we have a peer in the node map, we'll use their features here since we don't have
4037 // a way of figuring out their features from the invoice:
4038 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
4039 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(7));
4041 assert_eq!(route.paths[0].hops[3].pubkey, nodes[6]);
4042 assert_eq!(route.paths[0].hops[3].short_channel_id, 10);
4043 assert_eq!(route.paths[0].hops[3].fee_msat, 100);
4044 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, 42);
4045 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4046 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4048 // ...but still use 8 for larger payments as 6 has a variable feerate
4049 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 2000);
4050 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4051 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4052 assert_eq!(route.paths[0].hops.len(), 5);
4054 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
4055 assert_eq!(route.paths[0].hops[0].short_channel_id, 2);
4056 assert_eq!(route.paths[0].hops[0].fee_msat, 3000);
4057 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (4 << 4) | 1);
4058 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(2));
4059 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(2));
4061 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
4062 assert_eq!(route.paths[0].hops[1].short_channel_id, 4);
4063 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
4064 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (6 << 4) | 1);
4065 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
4066 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(4));
4068 assert_eq!(route.paths[0].hops[2].pubkey, nodes[4]);
4069 assert_eq!(route.paths[0].hops[2].short_channel_id, 6);
4070 assert_eq!(route.paths[0].hops[2].fee_msat, 0);
4071 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, (11 << 4) | 1);
4072 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(5));
4073 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(6));
4075 assert_eq!(route.paths[0].hops[3].pubkey, nodes[3]);
4076 assert_eq!(route.paths[0].hops[3].short_channel_id, 11);
4077 assert_eq!(route.paths[0].hops[3].fee_msat, 1000);
4078 assert_eq!(route.paths[0].hops[3].cltv_expiry_delta, (8 << 4) | 1);
4079 // If we have a peer in the node map, we'll use their features here since we don't have
4080 // a way of figuring out their features from the invoice:
4081 assert_eq!(route.paths[0].hops[3].node_features.le_flags(), &id_to_feature_flags(4));
4082 assert_eq!(route.paths[0].hops[3].channel_features.le_flags(), &id_to_feature_flags(11));
4084 assert_eq!(route.paths[0].hops[4].pubkey, nodes[6]);
4085 assert_eq!(route.paths[0].hops[4].short_channel_id, 8);
4086 assert_eq!(route.paths[0].hops[4].fee_msat, 2000);
4087 assert_eq!(route.paths[0].hops[4].cltv_expiry_delta, 42);
4088 assert_eq!(route.paths[0].hops[4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4089 assert_eq!(route.paths[0].hops[4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
4092 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> {
4093 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
4094 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4095 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4097 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
4098 let last_hops = RouteHint(vec![RouteHintHop {
4099 src_node_id: middle_node_id,
4100 short_channel_id: 8,
4103 proportional_millionths: last_hop_fee_prop,
4105 cltv_expiry_delta: (8 << 4) | 1,
4106 htlc_minimum_msat: None,
4107 htlc_maximum_msat: last_hop_htlc_max,
4109 let payment_params = PaymentParameters::from_node_id(target_node_id, 42).with_route_hints(vec![last_hops]).unwrap();
4110 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
4111 let scorer = ln_test_utils::TestScorer::new();
4112 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4113 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4114 let logger = ln_test_utils::TestLogger::new();
4115 let network_graph = NetworkGraph::new(Network::Testnet, &logger);
4116 let route_params = RouteParameters::from_payment_params_and_value(payment_params, route_val);
4117 let route = get_route(&source_node_id, &route_params, &network_graph.read_only(),
4118 Some(&our_chans.iter().collect::<Vec<_>>()), &logger, &scorer, &Default::default(),
4119 &random_seed_bytes);
4124 fn unannounced_path_test() {
4125 // We should be able to send a payment to a destination without any help of a routing graph
4126 // if we have a channel with a common counterparty that appears in the first and last hop
4128 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
4130 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
4131 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
4132 assert_eq!(route.paths[0].hops.len(), 2);
4134 assert_eq!(route.paths[0].hops[0].pubkey, middle_node_id);
4135 assert_eq!(route.paths[0].hops[0].short_channel_id, 42);
4136 assert_eq!(route.paths[0].hops[0].fee_msat, 1001);
4137 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (8 << 4) | 1);
4138 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &[0b11]);
4139 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4141 assert_eq!(route.paths[0].hops[1].pubkey, target_node_id);
4142 assert_eq!(route.paths[0].hops[1].short_channel_id, 8);
4143 assert_eq!(route.paths[0].hops[1].fee_msat, 1000000);
4144 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
4145 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
4146 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
4150 fn overflow_unannounced_path_test_liquidity_underflow() {
4151 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
4152 // the last-hop had a fee which overflowed a u64, we'd panic.
4153 // This was due to us adding the first-hop from us unconditionally, causing us to think
4154 // we'd built a path (as our node is in the "best candidate" set), when we had not.
4155 // In this test, we previously hit a subtraction underflow due to having less available
4156 // liquidity at the last hop than 0.
4157 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());
4161 fn overflow_unannounced_path_test_feerate_overflow() {
4162 // This tests for the same case as above, except instead of hitting a subtraction
4163 // underflow, we hit a case where the fee charged at a hop overflowed.
4164 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());
4168 fn available_amount_while_routing_test() {
4169 // Tests whether we choose the correct available channel amount while routing.
4171 let (secp_ctx, network_graph, gossip_sync, chain_monitor, logger) = build_graph();
4172 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4173 let scorer = ln_test_utils::TestScorer::new();
4174 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4175 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4176 let config = UserConfig::default();
4177 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4179 // We will use a simple single-path route from
4180 // our node to node2 via node0: channels {1, 3}.
4182 // First disable all other paths.
4183 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4184 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4185 short_channel_id: 2,
4188 cltv_expiry_delta: 0,
4189 htlc_minimum_msat: 0,
4190 htlc_maximum_msat: 100_000,
4192 fee_proportional_millionths: 0,
4193 excess_data: Vec::new()
4195 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4196 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4197 short_channel_id: 12,
4200 cltv_expiry_delta: 0,
4201 htlc_minimum_msat: 0,
4202 htlc_maximum_msat: 100_000,
4204 fee_proportional_millionths: 0,
4205 excess_data: Vec::new()
4208 // Make the first channel (#1) very permissive,
4209 // and we will be testing all limits on the second channel.
4210 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4211 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4212 short_channel_id: 1,
4215 cltv_expiry_delta: 0,
4216 htlc_minimum_msat: 0,
4217 htlc_maximum_msat: 1_000_000_000,
4219 fee_proportional_millionths: 0,
4220 excess_data: Vec::new()
4223 // First, let's see if routing works if we have absolutely no idea about the available amount.
4224 // In this case, it should be set to 250_000 sats.
4225 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4226 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4227 short_channel_id: 3,
4230 cltv_expiry_delta: 0,
4231 htlc_minimum_msat: 0,
4232 htlc_maximum_msat: 250_000_000,
4234 fee_proportional_millionths: 0,
4235 excess_data: Vec::new()
4239 // Attempt to route more than available results in a failure.
4240 let route_params = RouteParameters::from_payment_params_and_value(
4241 payment_params.clone(), 250_000_001);
4242 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4243 &our_id, &route_params, &network_graph.read_only(), None,
4244 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4245 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4246 } else { panic!(); }
4250 // Now, attempt to route an exact amount we have should be fine.
4251 let route_params = RouteParameters::from_payment_params_and_value(
4252 payment_params.clone(), 250_000_000);
4253 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4254 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4255 assert_eq!(route.paths.len(), 1);
4256 let path = route.paths.last().unwrap();
4257 assert_eq!(path.hops.len(), 2);
4258 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4259 assert_eq!(path.final_value_msat(), 250_000_000);
4262 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
4263 // Disable channel #1 and use another first hop.
4264 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4265 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4266 short_channel_id: 1,
4269 cltv_expiry_delta: 0,
4270 htlc_minimum_msat: 0,
4271 htlc_maximum_msat: 1_000_000_000,
4273 fee_proportional_millionths: 0,
4274 excess_data: Vec::new()
4277 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
4278 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
4281 // Attempt to route more than available results in a failure.
4282 let route_params = RouteParameters::from_payment_params_and_value(
4283 payment_params.clone(), 200_000_001);
4284 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4285 &our_id, &route_params, &network_graph.read_only(),
4286 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4287 &Default::default(), &random_seed_bytes) {
4288 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4289 } else { panic!(); }
4293 // Now, attempt to route an exact amount we have should be fine.
4294 let route_params = RouteParameters::from_payment_params_and_value(
4295 payment_params.clone(), 200_000_000);
4296 let route = get_route(&our_id, &route_params, &network_graph.read_only(),
4297 Some(&our_chans.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
4298 &Default::default(), &random_seed_bytes).unwrap();
4299 assert_eq!(route.paths.len(), 1);
4300 let path = route.paths.last().unwrap();
4301 assert_eq!(path.hops.len(), 2);
4302 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4303 assert_eq!(path.final_value_msat(), 200_000_000);
4306 // Enable channel #1 back.
4307 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4308 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4309 short_channel_id: 1,
4312 cltv_expiry_delta: 0,
4313 htlc_minimum_msat: 0,
4314 htlc_maximum_msat: 1_000_000_000,
4316 fee_proportional_millionths: 0,
4317 excess_data: Vec::new()
4321 // Now let's see if routing works if we know only htlc_maximum_msat.
4322 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4323 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4324 short_channel_id: 3,
4327 cltv_expiry_delta: 0,
4328 htlc_minimum_msat: 0,
4329 htlc_maximum_msat: 15_000,
4331 fee_proportional_millionths: 0,
4332 excess_data: Vec::new()
4336 // Attempt to route more than available results in a failure.
4337 let route_params = RouteParameters::from_payment_params_and_value(
4338 payment_params.clone(), 15_001);
4339 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4340 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4341 &scorer, &Default::default(), &random_seed_bytes) {
4342 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4343 } else { panic!(); }
4347 // Now, attempt to route an exact amount we have should be fine.
4348 let route_params = RouteParameters::from_payment_params_and_value(
4349 payment_params.clone(), 15_000);
4350 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4351 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4352 assert_eq!(route.paths.len(), 1);
4353 let path = route.paths.last().unwrap();
4354 assert_eq!(path.hops.len(), 2);
4355 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4356 assert_eq!(path.final_value_msat(), 15_000);
4359 // Now let's see if routing works if we know only capacity from the UTXO.
4361 // We can't change UTXO capacity on the fly, so we'll disable
4362 // the existing channel and add another one with the capacity we need.
4363 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4364 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4365 short_channel_id: 3,
4368 cltv_expiry_delta: 0,
4369 htlc_minimum_msat: 0,
4370 htlc_maximum_msat: MAX_VALUE_MSAT,
4372 fee_proportional_millionths: 0,
4373 excess_data: Vec::new()
4376 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
4377 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
4378 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
4379 .push_opcode(opcodes::all::OP_PUSHNUM_2)
4380 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
4382 *chain_monitor.utxo_ret.lock().unwrap() =
4383 UtxoResult::Sync(Ok(TxOut { value: 15, script_pubkey: good_script.clone() }));
4384 gossip_sync.add_utxo_lookup(Some(chain_monitor));
4386 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
4387 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4388 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4389 short_channel_id: 333,
4392 cltv_expiry_delta: (3 << 4) | 1,
4393 htlc_minimum_msat: 0,
4394 htlc_maximum_msat: 15_000,
4396 fee_proportional_millionths: 0,
4397 excess_data: Vec::new()
4399 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4400 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4401 short_channel_id: 333,
4404 cltv_expiry_delta: (3 << 4) | 2,
4405 htlc_minimum_msat: 0,
4406 htlc_maximum_msat: 15_000,
4408 fee_proportional_millionths: 0,
4409 excess_data: Vec::new()
4413 // Attempt to route more than available results in a failure.
4414 let route_params = RouteParameters::from_payment_params_and_value(
4415 payment_params.clone(), 15_001);
4416 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4417 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4418 &scorer, &Default::default(), &random_seed_bytes) {
4419 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4420 } else { panic!(); }
4424 // Now, attempt to route an exact amount we have should be fine.
4425 let route_params = RouteParameters::from_payment_params_and_value(
4426 payment_params.clone(), 15_000);
4427 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4428 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4429 assert_eq!(route.paths.len(), 1);
4430 let path = route.paths.last().unwrap();
4431 assert_eq!(path.hops.len(), 2);
4432 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4433 assert_eq!(path.final_value_msat(), 15_000);
4436 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
4437 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4438 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4439 short_channel_id: 333,
4442 cltv_expiry_delta: 0,
4443 htlc_minimum_msat: 0,
4444 htlc_maximum_msat: 10_000,
4446 fee_proportional_millionths: 0,
4447 excess_data: Vec::new()
4451 // Attempt to route more than available results in a failure.
4452 let route_params = RouteParameters::from_payment_params_and_value(
4453 payment_params.clone(), 10_001);
4454 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4455 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4456 &scorer, &Default::default(), &random_seed_bytes) {
4457 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4458 } else { panic!(); }
4462 // Now, attempt to route an exact amount we have should be fine.
4463 let route_params = RouteParameters::from_payment_params_and_value(
4464 payment_params.clone(), 10_000);
4465 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4466 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4467 assert_eq!(route.paths.len(), 1);
4468 let path = route.paths.last().unwrap();
4469 assert_eq!(path.hops.len(), 2);
4470 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4471 assert_eq!(path.final_value_msat(), 10_000);
4476 fn available_liquidity_last_hop_test() {
4477 // Check that available liquidity properly limits the path even when only
4478 // one of the latter hops is limited.
4479 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4480 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4481 let scorer = ln_test_utils::TestScorer::new();
4482 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4483 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4484 let config = UserConfig::default();
4485 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4487 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4488 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
4489 // Total capacity: 50 sats.
4491 // Disable other potential paths.
4492 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4493 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4494 short_channel_id: 2,
4497 cltv_expiry_delta: 0,
4498 htlc_minimum_msat: 0,
4499 htlc_maximum_msat: 100_000,
4501 fee_proportional_millionths: 0,
4502 excess_data: Vec::new()
4504 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4505 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4506 short_channel_id: 7,
4509 cltv_expiry_delta: 0,
4510 htlc_minimum_msat: 0,
4511 htlc_maximum_msat: 100_000,
4513 fee_proportional_millionths: 0,
4514 excess_data: Vec::new()
4519 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4520 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4521 short_channel_id: 12,
4524 cltv_expiry_delta: 0,
4525 htlc_minimum_msat: 0,
4526 htlc_maximum_msat: 100_000,
4528 fee_proportional_millionths: 0,
4529 excess_data: Vec::new()
4531 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4532 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4533 short_channel_id: 13,
4536 cltv_expiry_delta: 0,
4537 htlc_minimum_msat: 0,
4538 htlc_maximum_msat: 100_000,
4540 fee_proportional_millionths: 0,
4541 excess_data: Vec::new()
4544 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4545 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4546 short_channel_id: 6,
4549 cltv_expiry_delta: 0,
4550 htlc_minimum_msat: 0,
4551 htlc_maximum_msat: 50_000,
4553 fee_proportional_millionths: 0,
4554 excess_data: Vec::new()
4556 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4557 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4558 short_channel_id: 11,
4561 cltv_expiry_delta: 0,
4562 htlc_minimum_msat: 0,
4563 htlc_maximum_msat: 100_000,
4565 fee_proportional_millionths: 0,
4566 excess_data: Vec::new()
4569 // Attempt to route more than available results in a failure.
4570 let route_params = RouteParameters::from_payment_params_and_value(
4571 payment_params.clone(), 60_000);
4572 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4573 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
4574 &scorer, &Default::default(), &random_seed_bytes) {
4575 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4576 } else { panic!(); }
4580 // Now, attempt to route 49 sats (just a bit below the capacity).
4581 let route_params = RouteParameters::from_payment_params_and_value(
4582 payment_params.clone(), 49_000);
4583 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4584 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4585 assert_eq!(route.paths.len(), 1);
4586 let mut total_amount_paid_msat = 0;
4587 for path in &route.paths {
4588 assert_eq!(path.hops.len(), 4);
4589 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4590 total_amount_paid_msat += path.final_value_msat();
4592 assert_eq!(total_amount_paid_msat, 49_000);
4596 // Attempt to route an exact amount is also fine
4597 let route_params = RouteParameters::from_payment_params_and_value(
4598 payment_params, 50_000);
4599 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4600 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4601 assert_eq!(route.paths.len(), 1);
4602 let mut total_amount_paid_msat = 0;
4603 for path in &route.paths {
4604 assert_eq!(path.hops.len(), 4);
4605 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
4606 total_amount_paid_msat += path.final_value_msat();
4608 assert_eq!(total_amount_paid_msat, 50_000);
4613 fn ignore_fee_first_hop_test() {
4614 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4615 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4616 let scorer = ln_test_utils::TestScorer::new();
4617 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4618 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4619 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
4621 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4622 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4624 short_channel_id: 1,
4627 cltv_expiry_delta: 0,
4628 htlc_minimum_msat: 0,
4629 htlc_maximum_msat: 100_000,
4630 fee_base_msat: 1_000_000,
4631 fee_proportional_millionths: 0,
4632 excess_data: Vec::new()
4634 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4635 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4636 short_channel_id: 3,
4639 cltv_expiry_delta: 0,
4640 htlc_minimum_msat: 0,
4641 htlc_maximum_msat: 50_000,
4643 fee_proportional_millionths: 0,
4644 excess_data: Vec::new()
4648 let route_params = RouteParameters::from_payment_params_and_value(
4649 payment_params, 50_000);
4650 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4651 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4652 assert_eq!(route.paths.len(), 1);
4653 let mut total_amount_paid_msat = 0;
4654 for path in &route.paths {
4655 assert_eq!(path.hops.len(), 2);
4656 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4657 total_amount_paid_msat += path.final_value_msat();
4659 assert_eq!(total_amount_paid_msat, 50_000);
4664 fn simple_mpp_route_test() {
4665 let (secp_ctx, _, _, _, _) = build_graph();
4666 let (_, _, _, nodes) = get_nodes(&secp_ctx);
4667 let config = UserConfig::default();
4668 let clear_payment_params = PaymentParameters::from_node_id(nodes[2], 42)
4669 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4670 do_simple_mpp_route_test(clear_payment_params);
4672 // MPP to a 1-hop blinded path for nodes[2]
4673 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
4674 let blinded_path = BlindedPath {
4675 introduction_node_id: nodes[2],
4676 blinding_point: ln_test_utils::pubkey(42),
4677 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }],
4679 let blinded_payinfo = BlindedPayInfo { // These fields are ignored for 1-hop blinded paths
4681 fee_proportional_millionths: 0,
4682 htlc_minimum_msat: 0,
4683 htlc_maximum_msat: 0,
4684 cltv_expiry_delta: 0,
4685 features: BlindedHopFeatures::empty(),
4687 let one_hop_blinded_payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())])
4688 .with_bolt12_features(bolt12_features.clone()).unwrap();
4689 do_simple_mpp_route_test(one_hop_blinded_payment_params.clone());
4691 // MPP to 3 2-hop blinded paths
4692 let mut blinded_path_node_0 = blinded_path.clone();
4693 blinded_path_node_0.introduction_node_id = nodes[0];
4694 blinded_path_node_0.blinded_hops.push(blinded_path.blinded_hops[0].clone());
4695 let mut node_0_payinfo = blinded_payinfo.clone();
4696 node_0_payinfo.htlc_maximum_msat = 50_000;
4698 let mut blinded_path_node_7 = blinded_path_node_0.clone();
4699 blinded_path_node_7.introduction_node_id = nodes[7];
4700 let mut node_7_payinfo = blinded_payinfo.clone();
4701 node_7_payinfo.htlc_maximum_msat = 60_000;
4703 let mut blinded_path_node_1 = blinded_path_node_0.clone();
4704 blinded_path_node_1.introduction_node_id = nodes[1];
4705 let mut node_1_payinfo = blinded_payinfo.clone();
4706 node_1_payinfo.htlc_maximum_msat = 180_000;
4708 let two_hop_blinded_payment_params = PaymentParameters::blinded(
4710 (node_0_payinfo, blinded_path_node_0),
4711 (node_7_payinfo, blinded_path_node_7),
4712 (node_1_payinfo, blinded_path_node_1)
4714 .with_bolt12_features(bolt12_features).unwrap();
4715 do_simple_mpp_route_test(two_hop_blinded_payment_params);
4719 fn do_simple_mpp_route_test(payment_params: PaymentParameters) {
4720 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4721 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4722 let scorer = ln_test_utils::TestScorer::new();
4723 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4724 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4726 // We need a route consisting of 3 paths:
4727 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4728 // To achieve this, the amount being transferred should be around
4729 // the total capacity of these 3 paths.
4731 // First, we set limits on these (previously unlimited) channels.
4732 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4734 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4735 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4736 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4737 short_channel_id: 1,
4740 cltv_expiry_delta: 0,
4741 htlc_minimum_msat: 0,
4742 htlc_maximum_msat: 100_000,
4744 fee_proportional_millionths: 0,
4745 excess_data: Vec::new()
4747 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4748 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4749 short_channel_id: 3,
4752 cltv_expiry_delta: 0,
4753 htlc_minimum_msat: 0,
4754 htlc_maximum_msat: 50_000,
4756 fee_proportional_millionths: 0,
4757 excess_data: Vec::new()
4760 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4761 // (total limit 60).
4762 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4763 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4764 short_channel_id: 12,
4767 cltv_expiry_delta: 0,
4768 htlc_minimum_msat: 0,
4769 htlc_maximum_msat: 60_000,
4771 fee_proportional_millionths: 0,
4772 excess_data: Vec::new()
4774 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4775 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4776 short_channel_id: 13,
4779 cltv_expiry_delta: 0,
4780 htlc_minimum_msat: 0,
4781 htlc_maximum_msat: 60_000,
4783 fee_proportional_millionths: 0,
4784 excess_data: Vec::new()
4787 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4788 // (total capacity 180 sats).
4789 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4790 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4791 short_channel_id: 2,
4794 cltv_expiry_delta: 0,
4795 htlc_minimum_msat: 0,
4796 htlc_maximum_msat: 200_000,
4798 fee_proportional_millionths: 0,
4799 excess_data: Vec::new()
4801 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4802 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4803 short_channel_id: 4,
4806 cltv_expiry_delta: 0,
4807 htlc_minimum_msat: 0,
4808 htlc_maximum_msat: 180_000,
4810 fee_proportional_millionths: 0,
4811 excess_data: Vec::new()
4815 // Attempt to route more than available results in a failure.
4816 let route_params = RouteParameters::from_payment_params_and_value(
4817 payment_params.clone(), 300_000);
4818 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4819 &our_id, &route_params, &network_graph.read_only(), None,
4820 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4821 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4822 } else { panic!(); }
4826 // Attempt to route while setting max_path_count to 0 results in a failure.
4827 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4828 let route_params = RouteParameters::from_payment_params_and_value(
4829 zero_payment_params, 100);
4830 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4831 &our_id, &route_params, &network_graph.read_only(), None,
4832 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4833 assert_eq!(err, "Can't find a route with no paths allowed.");
4834 } else { panic!(); }
4838 // Attempt to route while setting max_path_count to 3 results in a failure.
4839 // This is the case because the minimal_value_contribution_msat would require each path
4840 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4841 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4842 let route_params = RouteParameters::from_payment_params_and_value(
4843 fail_payment_params, 250_000);
4844 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4845 &our_id, &route_params, &network_graph.read_only(), None,
4846 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes) {
4847 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4848 } else { panic!(); }
4852 // Now, attempt to route 250 sats (just a bit below the capacity).
4853 // Our algorithm should provide us with these 3 paths.
4854 let route_params = RouteParameters::from_payment_params_and_value(
4855 payment_params.clone(), 250_000);
4856 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4857 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4858 assert_eq!(route.paths.len(), 3);
4859 let mut total_amount_paid_msat = 0;
4860 for path in &route.paths {
4861 if let Some(bt) = &path.blinded_tail {
4862 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4864 assert_eq!(path.hops.len(), 2);
4865 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4867 total_amount_paid_msat += path.final_value_msat();
4869 assert_eq!(total_amount_paid_msat, 250_000);
4873 // Attempt to route an exact amount is also fine
4874 let route_params = RouteParameters::from_payment_params_and_value(
4875 payment_params.clone(), 290_000);
4876 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
4877 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
4878 assert_eq!(route.paths.len(), 3);
4879 let mut total_amount_paid_msat = 0;
4880 for path in &route.paths {
4881 if payment_params.payee.blinded_route_hints().len() != 0 {
4882 assert!(path.blinded_tail.is_some()) } else { assert!(path.blinded_tail.is_none()) }
4883 if let Some(bt) = &path.blinded_tail {
4884 assert_eq!(path.hops.len() + if bt.hops.len() == 1 { 0 } else { 1 }, 2);
4885 if bt.hops.len() > 1 {
4886 assert_eq!(path.hops.last().unwrap().pubkey,
4887 payment_params.payee.blinded_route_hints().iter()
4888 .find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
4889 .map(|(_, p)| p.introduction_node_id).unwrap());
4891 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4894 assert_eq!(path.hops.len(), 2);
4895 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
4897 total_amount_paid_msat += path.final_value_msat();
4899 assert_eq!(total_amount_paid_msat, 290_000);
4904 fn long_mpp_route_test() {
4905 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4906 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4907 let scorer = ln_test_utils::TestScorer::new();
4908 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4909 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4910 let config = UserConfig::default();
4911 let payment_params = PaymentParameters::from_node_id(nodes[3], 42)
4912 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
4914 // We need a route consisting of 3 paths:
4915 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4916 // Note that these paths overlap (channels 5, 12, 13).
4917 // We will route 300 sats.
4918 // Each path will have 100 sats capacity, those channels which
4919 // are used twice will have 200 sats capacity.
4921 // Disable other potential paths.
4922 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4923 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4924 short_channel_id: 2,
4927 cltv_expiry_delta: 0,
4928 htlc_minimum_msat: 0,
4929 htlc_maximum_msat: 100_000,
4931 fee_proportional_millionths: 0,
4932 excess_data: Vec::new()
4934 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4935 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4936 short_channel_id: 7,
4939 cltv_expiry_delta: 0,
4940 htlc_minimum_msat: 0,
4941 htlc_maximum_msat: 100_000,
4943 fee_proportional_millionths: 0,
4944 excess_data: Vec::new()
4947 // Path via {node0, node2} is channels {1, 3, 5}.
4948 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4949 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4950 short_channel_id: 1,
4953 cltv_expiry_delta: 0,
4954 htlc_minimum_msat: 0,
4955 htlc_maximum_msat: 100_000,
4957 fee_proportional_millionths: 0,
4958 excess_data: Vec::new()
4960 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4962 short_channel_id: 3,
4965 cltv_expiry_delta: 0,
4966 htlc_minimum_msat: 0,
4967 htlc_maximum_msat: 100_000,
4969 fee_proportional_millionths: 0,
4970 excess_data: Vec::new()
4973 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4974 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4975 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4976 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4977 short_channel_id: 5,
4980 cltv_expiry_delta: 0,
4981 htlc_minimum_msat: 0,
4982 htlc_maximum_msat: 200_000,
4984 fee_proportional_millionths: 0,
4985 excess_data: Vec::new()
4988 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4989 // Add 100 sats to the capacities of {12, 13}, because these channels
4990 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4991 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4992 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4993 short_channel_id: 12,
4996 cltv_expiry_delta: 0,
4997 htlc_minimum_msat: 0,
4998 htlc_maximum_msat: 200_000,
5000 fee_proportional_millionths: 0,
5001 excess_data: Vec::new()
5003 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5004 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5005 short_channel_id: 13,
5008 cltv_expiry_delta: 0,
5009 htlc_minimum_msat: 0,
5010 htlc_maximum_msat: 200_000,
5012 fee_proportional_millionths: 0,
5013 excess_data: Vec::new()
5016 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5017 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5018 short_channel_id: 6,
5021 cltv_expiry_delta: 0,
5022 htlc_minimum_msat: 0,
5023 htlc_maximum_msat: 100_000,
5025 fee_proportional_millionths: 0,
5026 excess_data: Vec::new()
5028 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5029 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5030 short_channel_id: 11,
5033 cltv_expiry_delta: 0,
5034 htlc_minimum_msat: 0,
5035 htlc_maximum_msat: 100_000,
5037 fee_proportional_millionths: 0,
5038 excess_data: Vec::new()
5041 // Path via {node7, node2} is channels {12, 13, 5}.
5042 // We already limited them to 200 sats (they are used twice for 100 sats).
5043 // Nothing to do here.
5046 // Attempt to route more than available results in a failure.
5047 let route_params = RouteParameters::from_payment_params_and_value(
5048 payment_params.clone(), 350_000);
5049 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5050 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5051 &scorer, &Default::default(), &random_seed_bytes) {
5052 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5053 } else { panic!(); }
5057 // Now, attempt to route 300 sats (exact amount we can route).
5058 // Our algorithm should provide us with these 3 paths, 100 sats each.
5059 let route_params = RouteParameters::from_payment_params_and_value(
5060 payment_params, 300_000);
5061 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5062 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5063 assert_eq!(route.paths.len(), 3);
5065 let mut total_amount_paid_msat = 0;
5066 for path in &route.paths {
5067 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5068 total_amount_paid_msat += path.final_value_msat();
5070 assert_eq!(total_amount_paid_msat, 300_000);
5076 fn mpp_cheaper_route_test() {
5077 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5078 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5079 let scorer = ln_test_utils::TestScorer::new();
5080 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5081 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5082 let config = UserConfig::default();
5083 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5085 // This test checks that if we have two cheaper paths and one more expensive path,
5086 // so that liquidity-wise any 2 of 3 combination is sufficient,
5087 // two cheaper paths will be taken.
5088 // These paths have equal available liquidity.
5090 // We need a combination of 3 paths:
5091 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
5092 // Note that these paths overlap (channels 5, 12, 13).
5093 // Each path will have 100 sats capacity, those channels which
5094 // are used twice will have 200 sats capacity.
5096 // Disable other potential paths.
5097 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5098 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5099 short_channel_id: 2,
5102 cltv_expiry_delta: 0,
5103 htlc_minimum_msat: 0,
5104 htlc_maximum_msat: 100_000,
5106 fee_proportional_millionths: 0,
5107 excess_data: Vec::new()
5109 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5110 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5111 short_channel_id: 7,
5114 cltv_expiry_delta: 0,
5115 htlc_minimum_msat: 0,
5116 htlc_maximum_msat: 100_000,
5118 fee_proportional_millionths: 0,
5119 excess_data: Vec::new()
5122 // Path via {node0, node2} is channels {1, 3, 5}.
5123 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5124 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5125 short_channel_id: 1,
5128 cltv_expiry_delta: 0,
5129 htlc_minimum_msat: 0,
5130 htlc_maximum_msat: 100_000,
5132 fee_proportional_millionths: 0,
5133 excess_data: Vec::new()
5135 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5136 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5137 short_channel_id: 3,
5140 cltv_expiry_delta: 0,
5141 htlc_minimum_msat: 0,
5142 htlc_maximum_msat: 100_000,
5144 fee_proportional_millionths: 0,
5145 excess_data: Vec::new()
5148 // Capacity of 200 sats because this channel will be used by 3rd path as well.
5149 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5150 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5151 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5152 short_channel_id: 5,
5155 cltv_expiry_delta: 0,
5156 htlc_minimum_msat: 0,
5157 htlc_maximum_msat: 200_000,
5159 fee_proportional_millionths: 0,
5160 excess_data: Vec::new()
5163 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5164 // Add 100 sats to the capacities of {12, 13}, because these channels
5165 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
5166 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5167 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5168 short_channel_id: 12,
5171 cltv_expiry_delta: 0,
5172 htlc_minimum_msat: 0,
5173 htlc_maximum_msat: 200_000,
5175 fee_proportional_millionths: 0,
5176 excess_data: Vec::new()
5178 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5179 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5180 short_channel_id: 13,
5183 cltv_expiry_delta: 0,
5184 htlc_minimum_msat: 0,
5185 htlc_maximum_msat: 200_000,
5187 fee_proportional_millionths: 0,
5188 excess_data: Vec::new()
5191 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5192 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5193 short_channel_id: 6,
5196 cltv_expiry_delta: 0,
5197 htlc_minimum_msat: 0,
5198 htlc_maximum_msat: 100_000,
5199 fee_base_msat: 1_000,
5200 fee_proportional_millionths: 0,
5201 excess_data: Vec::new()
5203 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5204 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5205 short_channel_id: 11,
5208 cltv_expiry_delta: 0,
5209 htlc_minimum_msat: 0,
5210 htlc_maximum_msat: 100_000,
5212 fee_proportional_millionths: 0,
5213 excess_data: Vec::new()
5216 // Path via {node7, node2} is channels {12, 13, 5}.
5217 // We already limited them to 200 sats (they are used twice for 100 sats).
5218 // Nothing to do here.
5221 // Now, attempt to route 180 sats.
5222 // Our algorithm should provide us with these 2 paths.
5223 let route_params = RouteParameters::from_payment_params_and_value(
5224 payment_params, 180_000);
5225 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5226 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5227 assert_eq!(route.paths.len(), 2);
5229 let mut total_value_transferred_msat = 0;
5230 let mut total_paid_msat = 0;
5231 for path in &route.paths {
5232 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5233 total_value_transferred_msat += path.final_value_msat();
5234 for hop in &path.hops {
5235 total_paid_msat += hop.fee_msat;
5238 // If we paid fee, this would be higher.
5239 assert_eq!(total_value_transferred_msat, 180_000);
5240 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
5241 assert_eq!(total_fees_paid, 0);
5246 fn fees_on_mpp_route_test() {
5247 // This test makes sure that MPP algorithm properly takes into account
5248 // fees charged on the channels, by making the fees impactful:
5249 // if the fee is not properly accounted for, the behavior is different.
5250 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5251 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5252 let scorer = ln_test_utils::TestScorer::new();
5253 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5254 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5255 let config = UserConfig::default();
5256 let payment_params = PaymentParameters::from_node_id(nodes[3], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5258 // We need a route consisting of 2 paths:
5259 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
5260 // We will route 200 sats, Each path will have 100 sats capacity.
5262 // This test is not particularly stable: e.g.,
5263 // there's a way to route via {node0, node2, node4}.
5264 // It works while pathfinding is deterministic, but can be broken otherwise.
5265 // It's fine to ignore this concern for now.
5267 // Disable other potential paths.
5268 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5269 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5270 short_channel_id: 2,
5273 cltv_expiry_delta: 0,
5274 htlc_minimum_msat: 0,
5275 htlc_maximum_msat: 100_000,
5277 fee_proportional_millionths: 0,
5278 excess_data: Vec::new()
5281 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5282 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5283 short_channel_id: 7,
5286 cltv_expiry_delta: 0,
5287 htlc_minimum_msat: 0,
5288 htlc_maximum_msat: 100_000,
5290 fee_proportional_millionths: 0,
5291 excess_data: Vec::new()
5294 // Path via {node0, node2} is channels {1, 3, 5}.
5295 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5296 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5297 short_channel_id: 1,
5300 cltv_expiry_delta: 0,
5301 htlc_minimum_msat: 0,
5302 htlc_maximum_msat: 100_000,
5304 fee_proportional_millionths: 0,
5305 excess_data: Vec::new()
5307 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5308 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5309 short_channel_id: 3,
5312 cltv_expiry_delta: 0,
5313 htlc_minimum_msat: 0,
5314 htlc_maximum_msat: 100_000,
5316 fee_proportional_millionths: 0,
5317 excess_data: Vec::new()
5320 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5321 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5322 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5323 short_channel_id: 5,
5326 cltv_expiry_delta: 0,
5327 htlc_minimum_msat: 0,
5328 htlc_maximum_msat: 100_000,
5330 fee_proportional_millionths: 0,
5331 excess_data: Vec::new()
5334 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
5335 // All channels should be 100 sats capacity. But for the fee experiment,
5336 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
5337 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
5338 // 100 sats (and pay 150 sats in fees for the use of channel 6),
5339 // so no matter how large are other channels,
5340 // the whole path will be limited by 100 sats with just these 2 conditions:
5341 // - channel 12 capacity is 250 sats
5342 // - fee for channel 6 is 150 sats
5343 // Let's test this by enforcing these 2 conditions and removing other limits.
5344 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5345 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5346 short_channel_id: 12,
5349 cltv_expiry_delta: 0,
5350 htlc_minimum_msat: 0,
5351 htlc_maximum_msat: 250_000,
5353 fee_proportional_millionths: 0,
5354 excess_data: Vec::new()
5356 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5357 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5358 short_channel_id: 13,
5361 cltv_expiry_delta: 0,
5362 htlc_minimum_msat: 0,
5363 htlc_maximum_msat: MAX_VALUE_MSAT,
5365 fee_proportional_millionths: 0,
5366 excess_data: Vec::new()
5369 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5370 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5371 short_channel_id: 6,
5374 cltv_expiry_delta: 0,
5375 htlc_minimum_msat: 0,
5376 htlc_maximum_msat: MAX_VALUE_MSAT,
5377 fee_base_msat: 150_000,
5378 fee_proportional_millionths: 0,
5379 excess_data: Vec::new()
5381 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5382 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5383 short_channel_id: 11,
5386 cltv_expiry_delta: 0,
5387 htlc_minimum_msat: 0,
5388 htlc_maximum_msat: MAX_VALUE_MSAT,
5390 fee_proportional_millionths: 0,
5391 excess_data: Vec::new()
5395 // Attempt to route more than available results in a failure.
5396 let route_params = RouteParameters::from_payment_params_and_value(
5397 payment_params.clone(), 210_000);
5398 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5399 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5400 &scorer, &Default::default(), &random_seed_bytes) {
5401 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5402 } else { panic!(); }
5406 // Attempt to route while setting max_total_routing_fee_msat to 149_999 results in a failure.
5407 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5408 max_total_routing_fee_msat: Some(149_999) };
5409 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5410 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5411 &scorer, &(), &random_seed_bytes) {
5412 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5413 } else { panic!(); }
5417 // Now, attempt to route 200 sats (exact amount we can route).
5418 let route_params = RouteParameters { payment_params: payment_params.clone(), final_value_msat: 200_000,
5419 max_total_routing_fee_msat: Some(150_000) };
5420 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5421 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5422 assert_eq!(route.paths.len(), 2);
5424 let mut total_amount_paid_msat = 0;
5425 for path in &route.paths {
5426 assert_eq!(path.hops.last().unwrap().pubkey, nodes[3]);
5427 total_amount_paid_msat += path.final_value_msat();
5429 assert_eq!(total_amount_paid_msat, 200_000);
5430 assert_eq!(route.get_total_fees(), 150_000);
5435 fn mpp_with_last_hops() {
5436 // Previously, if we tried to send an MPP payment to a destination which was only reachable
5437 // via a single last-hop route hint, we'd fail to route if we first collected routes
5438 // totaling close but not quite enough to fund the full payment.
5440 // This was because we considered last-hop hints to have exactly the sought payment amount
5441 // instead of the amount we were trying to collect, needlessly limiting our path searching
5442 // at the very first hop.
5444 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
5445 // criterion to cause us to refuse all routes at the last hop hint which would be considered
5446 // to only have the remaining to-collect amount in available liquidity.
5448 // This bug appeared in production in some specific channel configurations.
5449 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5450 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5451 let scorer = ln_test_utils::TestScorer::new();
5452 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5453 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5454 let config = UserConfig::default();
5455 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap(), 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5456 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
5457 src_node_id: nodes[2],
5458 short_channel_id: 42,
5459 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
5460 cltv_expiry_delta: 42,
5461 htlc_minimum_msat: None,
5462 htlc_maximum_msat: None,
5463 }])]).unwrap().with_max_channel_saturation_power_of_half(0);
5465 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
5466 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
5467 // would first use the no-fee route and then fail to find a path along the second route as
5468 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
5469 // under 5% of our payment amount.
5470 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5471 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5472 short_channel_id: 1,
5475 cltv_expiry_delta: (5 << 4) | 5,
5476 htlc_minimum_msat: 0,
5477 htlc_maximum_msat: 99_000,
5478 fee_base_msat: u32::max_value(),
5479 fee_proportional_millionths: u32::max_value(),
5480 excess_data: Vec::new()
5482 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5483 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5484 short_channel_id: 2,
5487 cltv_expiry_delta: (5 << 4) | 3,
5488 htlc_minimum_msat: 0,
5489 htlc_maximum_msat: 99_000,
5490 fee_base_msat: u32::max_value(),
5491 fee_proportional_millionths: u32::max_value(),
5492 excess_data: Vec::new()
5494 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5495 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5496 short_channel_id: 4,
5499 cltv_expiry_delta: (4 << 4) | 1,
5500 htlc_minimum_msat: 0,
5501 htlc_maximum_msat: MAX_VALUE_MSAT,
5503 fee_proportional_millionths: 0,
5504 excess_data: Vec::new()
5506 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5507 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5508 short_channel_id: 13,
5510 flags: 0|2, // Channel disabled
5511 cltv_expiry_delta: (13 << 4) | 1,
5512 htlc_minimum_msat: 0,
5513 htlc_maximum_msat: MAX_VALUE_MSAT,
5515 fee_proportional_millionths: 2000000,
5516 excess_data: Vec::new()
5519 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
5521 let route_params = RouteParameters::from_payment_params_and_value(
5522 payment_params, 100_000);
5523 let mut route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5524 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5525 assert_eq!(route.paths.len(), 2);
5526 route.paths.sort_by_key(|path| path.hops[0].short_channel_id);
5527 // Paths are manually ordered ordered by SCID, so:
5528 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
5529 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
5530 assert_eq!(route.paths[0].hops[0].short_channel_id, 1);
5531 assert_eq!(route.paths[0].hops[0].fee_msat, 0);
5532 assert_eq!(route.paths[0].hops[2].fee_msat, 99_000);
5533 assert_eq!(route.paths[1].hops[0].short_channel_id, 2);
5534 assert_eq!(route.paths[1].hops[0].fee_msat, 1);
5535 assert_eq!(route.paths[1].hops[2].fee_msat, 1_000);
5536 assert_eq!(route.get_total_fees(), 1);
5537 assert_eq!(route.get_total_amount(), 100_000);
5541 fn drop_lowest_channel_mpp_route_test() {
5542 // This test checks that low-capacity channel is dropped when after
5543 // path finding we realize that we found more capacity than we need.
5544 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5545 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5546 let scorer = ln_test_utils::TestScorer::new();
5547 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5548 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5549 let config = UserConfig::default();
5550 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
5551 .with_max_channel_saturation_power_of_half(0);
5553 // We need a route consisting of 3 paths:
5554 // From our node to node2 via node0, node7, node1 (three paths one hop each).
5556 // The first and the second paths should be sufficient, but the third should be
5557 // cheaper, so that we select it but drop later.
5559 // First, we set limits on these (previously unlimited) channels.
5560 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
5562 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
5563 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5565 short_channel_id: 1,
5568 cltv_expiry_delta: 0,
5569 htlc_minimum_msat: 0,
5570 htlc_maximum_msat: 100_000,
5572 fee_proportional_millionths: 0,
5573 excess_data: Vec::new()
5575 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
5576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5577 short_channel_id: 3,
5580 cltv_expiry_delta: 0,
5581 htlc_minimum_msat: 0,
5582 htlc_maximum_msat: 50_000,
5584 fee_proportional_millionths: 0,
5585 excess_data: Vec::new()
5588 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
5589 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5590 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5591 short_channel_id: 12,
5594 cltv_expiry_delta: 0,
5595 htlc_minimum_msat: 0,
5596 htlc_maximum_msat: 60_000,
5598 fee_proportional_millionths: 0,
5599 excess_data: Vec::new()
5601 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5602 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5603 short_channel_id: 13,
5606 cltv_expiry_delta: 0,
5607 htlc_minimum_msat: 0,
5608 htlc_maximum_msat: 60_000,
5610 fee_proportional_millionths: 0,
5611 excess_data: Vec::new()
5614 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
5615 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5616 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5617 short_channel_id: 2,
5620 cltv_expiry_delta: 0,
5621 htlc_minimum_msat: 0,
5622 htlc_maximum_msat: 20_000,
5624 fee_proportional_millionths: 0,
5625 excess_data: Vec::new()
5627 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5628 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5629 short_channel_id: 4,
5632 cltv_expiry_delta: 0,
5633 htlc_minimum_msat: 0,
5634 htlc_maximum_msat: 20_000,
5636 fee_proportional_millionths: 0,
5637 excess_data: Vec::new()
5641 // Attempt to route more than available results in a failure.
5642 let route_params = RouteParameters::from_payment_params_and_value(
5643 payment_params.clone(), 150_000);
5644 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
5645 &our_id, &route_params, &network_graph.read_only(), None, Arc::clone(&logger),
5646 &scorer, &Default::default(), &random_seed_bytes) {
5647 assert_eq!(err, "Failed to find a sufficient route to the given destination");
5648 } else { panic!(); }
5652 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
5653 // Our algorithm should provide us with these 3 paths.
5654 let route_params = RouteParameters::from_payment_params_and_value(
5655 payment_params.clone(), 125_000);
5656 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5657 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5658 assert_eq!(route.paths.len(), 3);
5659 let mut total_amount_paid_msat = 0;
5660 for path in &route.paths {
5661 assert_eq!(path.hops.len(), 2);
5662 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5663 total_amount_paid_msat += path.final_value_msat();
5665 assert_eq!(total_amount_paid_msat, 125_000);
5669 // Attempt to route without the last small cheap channel
5670 let route_params = RouteParameters::from_payment_params_and_value(
5671 payment_params, 90_000);
5672 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5673 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5674 assert_eq!(route.paths.len(), 2);
5675 let mut total_amount_paid_msat = 0;
5676 for path in &route.paths {
5677 assert_eq!(path.hops.len(), 2);
5678 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
5679 total_amount_paid_msat += path.final_value_msat();
5681 assert_eq!(total_amount_paid_msat, 90_000);
5686 fn min_criteria_consistency() {
5687 // Test that we don't use an inconsistent metric between updating and walking nodes during
5688 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5689 // was updated with a different criterion from the heap sorting, resulting in loops in
5690 // calculated paths. We test for that specific case here.
5692 // We construct a network that looks like this:
5694 // node2 -1(3)2- node3
5698 // node1 -1(5)2- node4 -1(1)2- node6
5704 // We create a loop on the side of our real path - our destination is node 6, with a
5705 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5706 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5707 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5708 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5709 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5710 // "previous hop" being set to node 3, creating a loop in the path.
5711 let secp_ctx = Secp256k1::new();
5712 let logger = Arc::new(ln_test_utils::TestLogger::new());
5713 let network = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
5714 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5715 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5716 let scorer = ln_test_utils::TestScorer::new();
5717 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5718 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5719 let payment_params = PaymentParameters::from_node_id(nodes[6], 42);
5721 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5722 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5723 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5724 short_channel_id: 6,
5727 cltv_expiry_delta: (6 << 4) | 0,
5728 htlc_minimum_msat: 0,
5729 htlc_maximum_msat: MAX_VALUE_MSAT,
5731 fee_proportional_millionths: 0,
5732 excess_data: Vec::new()
5734 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5736 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5737 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5738 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5739 short_channel_id: 5,
5742 cltv_expiry_delta: (5 << 4) | 0,
5743 htlc_minimum_msat: 0,
5744 htlc_maximum_msat: MAX_VALUE_MSAT,
5746 fee_proportional_millionths: 0,
5747 excess_data: Vec::new()
5749 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5751 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5752 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5753 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5754 short_channel_id: 4,
5757 cltv_expiry_delta: (4 << 4) | 0,
5758 htlc_minimum_msat: 0,
5759 htlc_maximum_msat: MAX_VALUE_MSAT,
5761 fee_proportional_millionths: 0,
5762 excess_data: Vec::new()
5764 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5766 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5767 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5768 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5769 short_channel_id: 3,
5772 cltv_expiry_delta: (3 << 4) | 0,
5773 htlc_minimum_msat: 0,
5774 htlc_maximum_msat: MAX_VALUE_MSAT,
5776 fee_proportional_millionths: 0,
5777 excess_data: Vec::new()
5779 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5781 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5782 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5783 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5784 short_channel_id: 2,
5787 cltv_expiry_delta: (2 << 4) | 0,
5788 htlc_minimum_msat: 0,
5789 htlc_maximum_msat: MAX_VALUE_MSAT,
5791 fee_proportional_millionths: 0,
5792 excess_data: Vec::new()
5795 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5796 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5797 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5798 short_channel_id: 1,
5801 cltv_expiry_delta: (1 << 4) | 0,
5802 htlc_minimum_msat: 100,
5803 htlc_maximum_msat: MAX_VALUE_MSAT,
5805 fee_proportional_millionths: 0,
5806 excess_data: Vec::new()
5808 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5811 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5812 let route_params = RouteParameters::from_payment_params_and_value(
5813 payment_params, 10_000);
5814 let route = get_route(&our_id, &route_params, &network.read_only(), None,
5815 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5816 assert_eq!(route.paths.len(), 1);
5817 assert_eq!(route.paths[0].hops.len(), 3);
5819 assert_eq!(route.paths[0].hops[0].pubkey, nodes[1]);
5820 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
5821 assert_eq!(route.paths[0].hops[0].fee_msat, 100);
5822 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (5 << 4) | 0);
5823 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(1));
5824 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(6));
5826 assert_eq!(route.paths[0].hops[1].pubkey, nodes[4]);
5827 assert_eq!(route.paths[0].hops[1].short_channel_id, 5);
5828 assert_eq!(route.paths[0].hops[1].fee_msat, 0);
5829 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, (1 << 4) | 0);
5830 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(4));
5831 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(5));
5833 assert_eq!(route.paths[0].hops[2].pubkey, nodes[6]);
5834 assert_eq!(route.paths[0].hops[2].short_channel_id, 1);
5835 assert_eq!(route.paths[0].hops[2].fee_msat, 10_000);
5836 assert_eq!(route.paths[0].hops[2].cltv_expiry_delta, 42);
5837 assert_eq!(route.paths[0].hops[2].node_features.le_flags(), &id_to_feature_flags(6));
5838 assert_eq!(route.paths[0].hops[2].channel_features.le_flags(), &id_to_feature_flags(1));
5844 fn exact_fee_liquidity_limit() {
5845 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5846 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5847 // we calculated fees on a higher value, resulting in us ignoring such paths.
5848 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5849 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5850 let scorer = ln_test_utils::TestScorer::new();
5851 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5852 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5853 let payment_params = PaymentParameters::from_node_id(nodes[2], 42);
5855 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5857 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5858 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5859 short_channel_id: 2,
5862 cltv_expiry_delta: 0,
5863 htlc_minimum_msat: 0,
5864 htlc_maximum_msat: 85_000,
5866 fee_proportional_millionths: 0,
5867 excess_data: Vec::new()
5870 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5871 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5872 short_channel_id: 12,
5875 cltv_expiry_delta: (4 << 4) | 1,
5876 htlc_minimum_msat: 0,
5877 htlc_maximum_msat: 270_000,
5879 fee_proportional_millionths: 1000000,
5880 excess_data: Vec::new()
5884 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5885 // 200% fee charged channel 13 in the 1-to-2 direction.
5886 let mut route_params = RouteParameters::from_payment_params_and_value(
5887 payment_params, 90_000);
5888 route_params.max_total_routing_fee_msat = Some(90_000*2);
5889 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5890 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5891 assert_eq!(route.paths.len(), 1);
5892 assert_eq!(route.paths[0].hops.len(), 2);
5894 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5895 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5896 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5897 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5898 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5899 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5901 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5902 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5903 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5904 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5905 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), &id_to_feature_flags(3));
5906 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5911 fn htlc_max_reduction_below_min() {
5912 // Test that if, while walking the graph, we reduce the value being sent to meet an
5913 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5914 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5915 // resulting in us thinking there is no possible path, even if other paths exist.
5916 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5917 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5918 let scorer = ln_test_utils::TestScorer::new();
5919 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5920 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5921 let config = UserConfig::default();
5922 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5924 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5925 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5926 // then try to send 90_000.
5927 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5928 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5929 short_channel_id: 2,
5932 cltv_expiry_delta: 0,
5933 htlc_minimum_msat: 0,
5934 htlc_maximum_msat: 80_000,
5936 fee_proportional_millionths: 0,
5937 excess_data: Vec::new()
5939 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5940 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5941 short_channel_id: 4,
5944 cltv_expiry_delta: (4 << 4) | 1,
5945 htlc_minimum_msat: 90_000,
5946 htlc_maximum_msat: MAX_VALUE_MSAT,
5948 fee_proportional_millionths: 0,
5949 excess_data: Vec::new()
5953 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5954 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5955 // expensive) channels 12-13 path.
5956 let mut route_params = RouteParameters::from_payment_params_and_value(
5957 payment_params, 90_000);
5958 route_params.max_total_routing_fee_msat = Some(90_000*2);
5959 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
5960 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
5961 assert_eq!(route.paths.len(), 1);
5962 assert_eq!(route.paths[0].hops.len(), 2);
5964 assert_eq!(route.paths[0].hops[0].pubkey, nodes[7]);
5965 assert_eq!(route.paths[0].hops[0].short_channel_id, 12);
5966 assert_eq!(route.paths[0].hops[0].fee_msat, 90_000*2);
5967 assert_eq!(route.paths[0].hops[0].cltv_expiry_delta, (13 << 4) | 1);
5968 assert_eq!(route.paths[0].hops[0].node_features.le_flags(), &id_to_feature_flags(8));
5969 assert_eq!(route.paths[0].hops[0].channel_features.le_flags(), &id_to_feature_flags(12));
5971 assert_eq!(route.paths[0].hops[1].pubkey, nodes[2]);
5972 assert_eq!(route.paths[0].hops[1].short_channel_id, 13);
5973 assert_eq!(route.paths[0].hops[1].fee_msat, 90_000);
5974 assert_eq!(route.paths[0].hops[1].cltv_expiry_delta, 42);
5975 assert_eq!(route.paths[0].hops[1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
5976 assert_eq!(route.paths[0].hops[1].channel_features.le_flags(), &id_to_feature_flags(13));
5981 fn multiple_direct_first_hops() {
5982 // Previously we'd only ever considered one first hop path per counterparty.
5983 // However, as we don't restrict users to one channel per peer, we really need to support
5984 // looking at all first hop paths.
5985 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5986 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5987 // route over multiple channels with the same first hop.
5988 let secp_ctx = Secp256k1::new();
5989 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5990 let logger = Arc::new(ln_test_utils::TestLogger::new());
5991 let network_graph = NetworkGraph::new(Network::Testnet, Arc::clone(&logger));
5992 let scorer = ln_test_utils::TestScorer::new();
5993 let config = UserConfig::default();
5994 let payment_params = PaymentParameters::from_node_id(nodes[0], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
5995 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5996 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5999 let route_params = RouteParameters::from_payment_params_and_value(
6000 payment_params.clone(), 100_000);
6001 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6002 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
6003 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
6004 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6005 assert_eq!(route.paths.len(), 1);
6006 assert_eq!(route.paths[0].hops.len(), 1);
6008 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6009 assert_eq!(route.paths[0].hops[0].short_channel_id, 3);
6010 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6013 let route_params = RouteParameters::from_payment_params_and_value(
6014 payment_params.clone(), 100_000);
6015 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6016 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6017 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6018 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6019 assert_eq!(route.paths.len(), 2);
6020 assert_eq!(route.paths[0].hops.len(), 1);
6021 assert_eq!(route.paths[1].hops.len(), 1);
6023 assert!((route.paths[0].hops[0].short_channel_id == 3 && route.paths[1].hops[0].short_channel_id == 2) ||
6024 (route.paths[0].hops[0].short_channel_id == 2 && route.paths[1].hops[0].short_channel_id == 3));
6026 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6027 assert_eq!(route.paths[0].hops[0].fee_msat, 50_000);
6029 assert_eq!(route.paths[1].hops[0].pubkey, nodes[0]);
6030 assert_eq!(route.paths[1].hops[0].fee_msat, 50_000);
6034 // If we have a bunch of outbound channels to the same node, where most are not
6035 // sufficient to pay the full payment, but one is, we should default to just using the
6036 // one single channel that has sufficient balance, avoiding MPP.
6038 // If we have several options above the 3xpayment value threshold, we should pick the
6039 // smallest of them, avoiding further fragmenting our available outbound balance to
6041 let route_params = RouteParameters::from_payment_params_and_value(
6042 payment_params, 100_000);
6043 let route = get_route(&our_id, &route_params, &network_graph.read_only(), Some(&[
6044 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6045 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6046 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6047 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
6048 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6049 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6050 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
6051 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
6052 ]), Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6053 assert_eq!(route.paths.len(), 1);
6054 assert_eq!(route.paths[0].hops.len(), 1);
6056 assert_eq!(route.paths[0].hops[0].pubkey, nodes[0]);
6057 assert_eq!(route.paths[0].hops[0].short_channel_id, 6);
6058 assert_eq!(route.paths[0].hops[0].fee_msat, 100_000);
6063 fn prefers_shorter_route_with_higher_fees() {
6064 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6065 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6066 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6068 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
6069 let scorer = ln_test_utils::TestScorer::new();
6070 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6071 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6072 let route_params = RouteParameters::from_payment_params_and_value(
6073 payment_params.clone(), 100);
6074 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6075 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6076 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6078 assert_eq!(route.get_total_fees(), 100);
6079 assert_eq!(route.get_total_amount(), 100);
6080 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6082 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
6083 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
6084 let scorer = FixedPenaltyScorer::with_penalty(100);
6085 let route_params = RouteParameters::from_payment_params_and_value(
6086 payment_params, 100);
6087 let route = get_route( &our_id, &route_params, &network_graph.read_only(), None,
6088 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6089 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6091 assert_eq!(route.get_total_fees(), 300);
6092 assert_eq!(route.get_total_amount(), 100);
6093 assert_eq!(path, vec![2, 4, 7, 10]);
6096 struct BadChannelScorer {
6097 short_channel_id: u64,
6101 impl Writeable for BadChannelScorer {
6102 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6104 impl ScoreLookUp for BadChannelScorer {
6105 type ScoreParams = ();
6106 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6107 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
6111 struct BadNodeScorer {
6116 impl Writeable for BadNodeScorer {
6117 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
6120 impl ScoreLookUp for BadNodeScorer {
6121 type ScoreParams = ();
6122 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage, _score_params:&Self::ScoreParams) -> u64 {
6123 if *target == self.node_id { u64::max_value() } else { 0 }
6128 fn avoids_routing_through_bad_channels_and_nodes() {
6129 let (secp_ctx, network, _, _, logger) = build_graph();
6130 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6131 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6132 let network_graph = network.read_only();
6134 // A path to nodes[6] exists when no penalties are applied to any channel.
6135 let scorer = ln_test_utils::TestScorer::new();
6136 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6137 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6138 let route_params = RouteParameters::from_payment_params_and_value(
6139 payment_params, 100);
6140 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6141 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6142 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6144 assert_eq!(route.get_total_fees(), 100);
6145 assert_eq!(route.get_total_amount(), 100);
6146 assert_eq!(path, vec![2, 4, 6, 11, 8]);
6148 // A different path to nodes[6] exists if channel 6 cannot be routed over.
6149 let scorer = BadChannelScorer { short_channel_id: 6 };
6150 let route = get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6151 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6152 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6154 assert_eq!(route.get_total_fees(), 300);
6155 assert_eq!(route.get_total_amount(), 100);
6156 assert_eq!(path, vec![2, 4, 7, 10]);
6158 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
6159 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
6160 match get_route( &our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6161 &scorer, &Default::default(), &random_seed_bytes) {
6162 Err(LightningError { err, .. } ) => {
6163 assert_eq!(err, "Failed to find a path to the given destination");
6165 Ok(_) => panic!("Expected error"),
6170 fn total_fees_single_path() {
6172 paths: vec![Path { hops: vec![
6174 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6175 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6176 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6179 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6180 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6181 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6184 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
6185 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6186 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0, maybe_announced_channel: true,
6188 ], blinded_tail: None }],
6192 assert_eq!(route.get_total_fees(), 250);
6193 assert_eq!(route.get_total_amount(), 225);
6197 fn total_fees_multi_path() {
6199 paths: vec![Path { hops: vec![
6201 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6202 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6203 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6206 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6207 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6208 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6210 ], blinded_tail: None }, Path { hops: vec![
6212 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
6213 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6214 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0, maybe_announced_channel: true,
6217 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
6218 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
6219 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0, maybe_announced_channel: true,
6221 ], blinded_tail: None }],
6225 assert_eq!(route.get_total_fees(), 200);
6226 assert_eq!(route.get_total_amount(), 300);
6230 fn total_empty_route_no_panic() {
6231 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
6232 // would both panic if the route was completely empty. We test to ensure they return 0
6233 // here, even though its somewhat nonsensical as a route.
6234 let route = Route { paths: Vec::new(), route_params: None };
6236 assert_eq!(route.get_total_fees(), 0);
6237 assert_eq!(route.get_total_amount(), 0);
6241 fn limits_total_cltv_delta() {
6242 let (secp_ctx, network, _, _, logger) = build_graph();
6243 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6244 let network_graph = network.read_only();
6246 let scorer = ln_test_utils::TestScorer::new();
6248 // Make sure that generally there is at least one route available
6249 let feasible_max_total_cltv_delta = 1008;
6250 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6251 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
6252 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6253 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6254 let route_params = RouteParameters::from_payment_params_and_value(
6255 feasible_payment_params, 100);
6256 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6257 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6258 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6259 assert_ne!(path.len(), 0);
6261 // But not if we exclude all paths on the basis of their accumulated CLTV delta
6262 let fail_max_total_cltv_delta = 23;
6263 let fail_payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6264 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
6265 let route_params = RouteParameters::from_payment_params_and_value(
6266 fail_payment_params, 100);
6267 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6268 &Default::default(), &random_seed_bytes)
6270 Err(LightningError { err, .. } ) => {
6271 assert_eq!(err, "Failed to find a path to the given destination");
6273 Ok(_) => panic!("Expected error"),
6278 fn avoids_recently_failed_paths() {
6279 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
6280 // randomly inserting channels into it until we can't find a route anymore.
6281 let (secp_ctx, network, _, _, logger) = build_graph();
6282 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6283 let network_graph = network.read_only();
6285 let scorer = ln_test_utils::TestScorer::new();
6286 let mut payment_params = PaymentParameters::from_node_id(nodes[6], 0).with_route_hints(last_hops(&nodes)).unwrap()
6287 .with_max_path_count(1);
6288 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6289 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6291 // We should be able to find a route initially, and then after we fail a few random
6292 // channels eventually we won't be able to any longer.
6293 let route_params = RouteParameters::from_payment_params_and_value(
6294 payment_params.clone(), 100);
6295 assert!(get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6296 &scorer, &Default::default(), &random_seed_bytes).is_ok());
6298 let route_params = RouteParameters::from_payment_params_and_value(
6299 payment_params.clone(), 100);
6300 if let Ok(route) = get_route(&our_id, &route_params, &network_graph, None,
6301 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes)
6303 for chan in route.paths[0].hops.iter() {
6304 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
6306 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
6307 % route.paths[0].hops.len();
6308 payment_params.previously_failed_channels.push(route.paths[0].hops[victim].short_channel_id);
6314 fn limits_path_length() {
6315 let (secp_ctx, network, _, _, logger) = build_line_graph();
6316 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6317 let network_graph = network.read_only();
6319 let scorer = ln_test_utils::TestScorer::new();
6320 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6321 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6323 // First check we can actually create a long route on this graph.
6324 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18], 0);
6325 let route_params = RouteParameters::from_payment_params_and_value(
6326 feasible_payment_params, 100);
6327 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6328 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6329 let path = route.paths[0].hops.iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
6330 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
6332 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
6333 let fail_payment_params = PaymentParameters::from_node_id(nodes[19], 0);
6334 let route_params = RouteParameters::from_payment_params_and_value(
6335 fail_payment_params, 100);
6336 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
6337 &Default::default(), &random_seed_bytes)
6339 Err(LightningError { err, .. } ) => {
6340 assert_eq!(err, "Failed to find a path to the given destination");
6342 Ok(_) => panic!("Expected error"),
6347 fn adds_and_limits_cltv_offset() {
6348 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6349 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6351 let scorer = ln_test_utils::TestScorer::new();
6353 let payment_params = PaymentParameters::from_node_id(nodes[6], 42).with_route_hints(last_hops(&nodes)).unwrap();
6354 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6355 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6356 let route_params = RouteParameters::from_payment_params_and_value(
6357 payment_params.clone(), 100);
6358 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6359 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6360 assert_eq!(route.paths.len(), 1);
6362 let cltv_expiry_deltas_before = route.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6364 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
6365 let mut route_default = route.clone();
6366 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
6367 let cltv_expiry_deltas_default = route_default.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6368 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
6369 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
6370 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
6372 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
6373 let mut route_limited = route.clone();
6374 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
6375 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
6376 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
6377 let cltv_expiry_deltas_limited = route_limited.paths[0].hops.iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
6378 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
6382 fn adds_plausible_cltv_offset() {
6383 let (secp_ctx, network, _, _, logger) = build_graph();
6384 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6385 let network_graph = network.read_only();
6386 let network_nodes = network_graph.nodes();
6387 let network_channels = network_graph.channels();
6388 let scorer = ln_test_utils::TestScorer::new();
6389 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6390 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
6391 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6393 let route_params = RouteParameters::from_payment_params_and_value(
6394 payment_params.clone(), 100);
6395 let mut route = get_route(&our_id, &route_params, &network_graph, None,
6396 Arc::clone(&logger), &scorer, &Default::default(), &random_seed_bytes).unwrap();
6397 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
6399 let mut path_plausibility = vec![];
6401 for p in route.paths {
6402 // 1. Select random observation point
6403 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
6404 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
6406 prng.process_in_place(&mut random_bytes);
6407 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.hops.len());
6408 let observation_point = NodeId::from_pubkey(&p.hops.get(random_path_index).unwrap().pubkey);
6410 // 2. Calculate what CLTV expiry delta we would observe there
6411 let observed_cltv_expiry_delta: u32 = p.hops[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
6413 // 3. Starting from the observation point, find candidate paths
6414 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
6415 candidates.push_back((observation_point, vec![]));
6417 let mut found_plausible_candidate = false;
6419 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
6420 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
6421 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
6422 found_plausible_candidate = true;
6423 break 'candidate_loop;
6427 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
6428 for channel_id in &cur_node.channels {
6429 if let Some(channel_info) = network_channels.get(&channel_id) {
6430 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
6431 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
6432 if cur_path_cltv_deltas.iter().sum::<u32>()
6433 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
6434 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
6435 new_path_cltv_deltas.push(next_cltv_expiry_delta);
6436 candidates.push_back((*next_id, new_path_cltv_deltas));
6444 path_plausibility.push(found_plausible_candidate);
6446 assert!(path_plausibility.iter().all(|x| *x));
6450 fn builds_correct_path_from_hops() {
6451 let (secp_ctx, network, _, _, logger) = build_graph();
6452 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6453 let network_graph = network.read_only();
6455 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6456 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6458 let payment_params = PaymentParameters::from_node_id(nodes[3], 0);
6459 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
6460 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 100);
6461 let route = build_route_from_hops_internal(&our_id, &hops, &route_params, &network_graph,
6462 Arc::clone(&logger), &random_seed_bytes).unwrap();
6463 let route_hop_pubkeys = route.paths[0].hops.iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
6464 assert_eq!(hops.len(), route.paths[0].hops.len());
6465 for (idx, hop_pubkey) in hops.iter().enumerate() {
6466 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
6471 fn avoids_saturating_channels() {
6472 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
6473 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
6474 let decay_params = ProbabilisticScoringDecayParameters::default();
6475 let scorer = ProbabilisticScorer::new(decay_params, &*network_graph, Arc::clone(&logger));
6477 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
6478 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
6479 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
6480 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6481 short_channel_id: 4,
6484 cltv_expiry_delta: (4 << 4) | 1,
6485 htlc_minimum_msat: 0,
6486 htlc_maximum_msat: 250_000_000,
6488 fee_proportional_millionths: 0,
6489 excess_data: Vec::new()
6491 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
6492 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
6493 short_channel_id: 13,
6496 cltv_expiry_delta: (13 << 4) | 1,
6497 htlc_minimum_msat: 0,
6498 htlc_maximum_msat: 250_000_000,
6500 fee_proportional_millionths: 0,
6501 excess_data: Vec::new()
6504 let config = UserConfig::default();
6505 let payment_params = PaymentParameters::from_node_id(nodes[2], 42).with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6506 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6507 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6508 // 100,000 sats is less than the available liquidity on each channel, set above.
6509 let route_params = RouteParameters::from_payment_params_and_value(
6510 payment_params, 100_000_000);
6511 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6512 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(), &random_seed_bytes).unwrap();
6513 assert_eq!(route.paths.len(), 2);
6514 assert!((route.paths[0].hops[1].short_channel_id == 4 && route.paths[1].hops[1].short_channel_id == 13) ||
6515 (route.paths[1].hops[1].short_channel_id == 4 && route.paths[0].hops[1].short_channel_id == 13));
6518 #[cfg(not(feature = "no-std"))]
6519 pub(super) fn random_init_seed() -> u64 {
6520 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
6521 use core::hash::{BuildHasher, Hasher};
6522 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
6523 println!("Using seed of {}", seed);
6528 #[cfg(not(feature = "no-std"))]
6529 fn generate_routes() {
6530 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6532 let logger = ln_test_utils::TestLogger::new();
6533 let graph = match super::bench_utils::read_network_graph(&logger) {
6541 let params = ProbabilisticScoringFeeParameters::default();
6542 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6543 let features = super::Bolt11InvoiceFeatures::empty();
6545 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6549 #[cfg(not(feature = "no-std"))]
6550 fn generate_routes_mpp() {
6551 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6553 let logger = ln_test_utils::TestLogger::new();
6554 let graph = match super::bench_utils::read_network_graph(&logger) {
6562 let params = ProbabilisticScoringFeeParameters::default();
6563 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6564 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6566 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 0, 2);
6570 #[cfg(not(feature = "no-std"))]
6571 fn generate_large_mpp_routes() {
6572 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringFeeParameters};
6574 let logger = ln_test_utils::TestLogger::new();
6575 let graph = match super::bench_utils::read_network_graph(&logger) {
6583 let params = ProbabilisticScoringFeeParameters::default();
6584 let mut scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &graph, &logger);
6585 let features = channelmanager::provided_invoice_features(&UserConfig::default());
6587 super::bench_utils::generate_test_routes(&graph, &mut scorer, ¶ms, features, random_init_seed(), 1_000_000, 2);
6591 fn honors_manual_penalties() {
6592 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
6593 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6595 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6596 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6598 let mut scorer_params = ProbabilisticScoringFeeParameters::default();
6599 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), Arc::clone(&network_graph), Arc::clone(&logger));
6601 // First check set manual penalties are returned by the scorer.
6602 let usage = ChannelUsage {
6604 inflight_htlc_msat: 0,
6605 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
6607 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
6608 scorer_params.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
6609 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage, &scorer_params), 456);
6611 // Then check we can get a normal route
6612 let payment_params = PaymentParameters::from_node_id(nodes[10], 42);
6613 let route_params = RouteParameters::from_payment_params_and_value(
6614 payment_params, 100);
6615 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6616 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6617 assert!(route.is_ok());
6619 // Then check that we can't get a route if we ban an intermediate node.
6620 scorer_params.add_banned(&NodeId::from_pubkey(&nodes[3]));
6621 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6622 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6623 assert!(route.is_err());
6625 // Finally make sure we can route again, when we remove the ban.
6626 scorer_params.remove_banned(&NodeId::from_pubkey(&nodes[3]));
6627 let route = get_route(&our_id, &route_params, &network_graph.read_only(), None,
6628 Arc::clone(&logger), &scorer, &scorer_params, &random_seed_bytes);
6629 assert!(route.is_ok());
6633 fn abide_by_route_hint_max_htlc() {
6634 // Check that we abide by any htlc_maximum_msat provided in the route hints of the payment
6635 // params in the final route.
6636 let (secp_ctx, network_graph, _, _, logger) = build_graph();
6637 let netgraph = network_graph.read_only();
6638 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6639 let scorer = ln_test_utils::TestScorer::new();
6640 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6641 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6642 let config = UserConfig::default();
6644 let max_htlc_msat = 50_000;
6645 let route_hint_1 = RouteHint(vec![RouteHintHop {
6646 src_node_id: nodes[2],
6647 short_channel_id: 42,
6650 proportional_millionths: 0,
6652 cltv_expiry_delta: 10,
6653 htlc_minimum_msat: None,
6654 htlc_maximum_msat: Some(max_htlc_msat),
6656 let dest_node_id = ln_test_utils::pubkey(42);
6657 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6658 .with_route_hints(vec![route_hint_1.clone()]).unwrap()
6659 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6661 // Make sure we'll error if our route hints don't have enough liquidity according to their
6662 // htlc_maximum_msat.
6663 let mut route_params = RouteParameters::from_payment_params_and_value(
6664 payment_params, max_htlc_msat + 1);
6665 route_params.max_total_routing_fee_msat = None;
6666 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id,
6667 &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &Default::default(),
6670 assert_eq!(err, "Failed to find a sufficient route to the given destination");
6671 } else { panic!(); }
6673 // Make sure we'll split an MPP payment across route hints if their htlc_maximum_msat warrants.
6674 let mut route_hint_2 = route_hint_1.clone();
6675 route_hint_2.0[0].short_channel_id = 43;
6676 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6677 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6678 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6679 let mut route_params = RouteParameters::from_payment_params_and_value(
6680 payment_params, max_htlc_msat + 1);
6681 route_params.max_total_routing_fee_msat = Some(max_htlc_msat * 2);
6682 let route = get_route(&our_id, &route_params, &netgraph, None, Arc::clone(&logger),
6683 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6684 assert_eq!(route.paths.len(), 2);
6685 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6686 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6690 fn direct_channel_to_hints_with_max_htlc() {
6691 // Check that if we have a first hop channel peer that's connected to multiple provided route
6692 // hints, that we properly split the payment between the route hints if needed.
6693 let logger = Arc::new(ln_test_utils::TestLogger::new());
6694 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
6695 let scorer = ln_test_utils::TestScorer::new();
6696 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6697 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6698 let config = UserConfig::default();
6700 let our_node_id = ln_test_utils::pubkey(42);
6701 let intermed_node_id = ln_test_utils::pubkey(43);
6702 let first_hop = vec![get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
6704 let amt_msat = 900_000;
6705 let max_htlc_msat = 500_000;
6706 let route_hint_1 = RouteHint(vec![RouteHintHop {
6707 src_node_id: intermed_node_id,
6708 short_channel_id: 44,
6711 proportional_millionths: 0,
6713 cltv_expiry_delta: 10,
6714 htlc_minimum_msat: None,
6715 htlc_maximum_msat: Some(max_htlc_msat),
6717 src_node_id: intermed_node_id,
6718 short_channel_id: 45,
6721 proportional_millionths: 0,
6723 cltv_expiry_delta: 10,
6724 htlc_minimum_msat: None,
6725 // Check that later route hint max htlcs don't override earlier ones
6726 htlc_maximum_msat: Some(max_htlc_msat - 50),
6728 let mut route_hint_2 = route_hint_1.clone();
6729 route_hint_2.0[0].short_channel_id = 46;
6730 route_hint_2.0[1].short_channel_id = 47;
6731 let dest_node_id = ln_test_utils::pubkey(44);
6732 let payment_params = PaymentParameters::from_node_id(dest_node_id, 42)
6733 .with_route_hints(vec![route_hint_1, route_hint_2]).unwrap()
6734 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap();
6736 let route_params = RouteParameters::from_payment_params_and_value(
6737 payment_params, amt_msat);
6738 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6739 Some(&first_hop.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6740 &Default::default(), &random_seed_bytes).unwrap();
6741 assert_eq!(route.paths.len(), 2);
6742 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6743 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6744 assert_eq!(route.get_total_amount(), amt_msat);
6746 // Re-run but with two first hop channels connected to the same route hint peers that must be
6748 let first_hops = vec![
6749 get_channel_details(Some(42), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6750 get_channel_details(Some(43), intermed_node_id, InitFeatures::from_le_bytes(vec![0b11]), amt_msat - 10),
6752 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6753 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6754 &Default::default(), &random_seed_bytes).unwrap();
6755 assert_eq!(route.paths.len(), 2);
6756 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6757 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6758 assert_eq!(route.get_total_amount(), amt_msat);
6760 // Make sure this works for blinded route hints.
6761 let blinded_path = BlindedPath {
6762 introduction_node_id: intermed_node_id,
6763 blinding_point: ln_test_utils::pubkey(42),
6765 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42), encrypted_payload: vec![] },
6766 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![] },
6769 let blinded_payinfo = BlindedPayInfo {
6771 fee_proportional_millionths: 0,
6772 htlc_minimum_msat: 1,
6773 htlc_maximum_msat: max_htlc_msat,
6774 cltv_expiry_delta: 10,
6775 features: BlindedHopFeatures::empty(),
6777 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
6778 let payment_params = PaymentParameters::blinded(vec![
6779 (blinded_payinfo.clone(), blinded_path.clone()),
6780 (blinded_payinfo.clone(), blinded_path.clone())])
6781 .with_bolt12_features(bolt12_features).unwrap();
6782 let route_params = RouteParameters::from_payment_params_and_value(
6783 payment_params, amt_msat);
6784 let route = get_route(&our_node_id, &route_params, &network_graph.read_only(),
6785 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
6786 &Default::default(), &random_seed_bytes).unwrap();
6787 assert_eq!(route.paths.len(), 2);
6788 assert!(route.paths[0].hops.last().unwrap().fee_msat <= max_htlc_msat);
6789 assert!(route.paths[1].hops.last().unwrap().fee_msat <= max_htlc_msat);
6790 assert_eq!(route.get_total_amount(), amt_msat);
6794 fn blinded_route_ser() {
6795 let blinded_path_1 = BlindedPath {
6796 introduction_node_id: ln_test_utils::pubkey(42),
6797 blinding_point: ln_test_utils::pubkey(43),
6799 BlindedHop { blinded_node_id: ln_test_utils::pubkey(44), encrypted_payload: Vec::new() },
6800 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() }
6803 let blinded_path_2 = BlindedPath {
6804 introduction_node_id: ln_test_utils::pubkey(46),
6805 blinding_point: ln_test_utils::pubkey(47),
6807 BlindedHop { blinded_node_id: ln_test_utils::pubkey(48), encrypted_payload: Vec::new() },
6808 BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }
6811 // (De)serialize a Route with 1 blinded path out of two total paths.
6812 let mut route = Route { paths: vec![Path {
6813 hops: vec![RouteHop {
6814 pubkey: ln_test_utils::pubkey(50),
6815 node_features: NodeFeatures::empty(),
6816 short_channel_id: 42,
6817 channel_features: ChannelFeatures::empty(),
6819 cltv_expiry_delta: 0,
6820 maybe_announced_channel: true,
6822 blinded_tail: Some(BlindedTail {
6823 hops: blinded_path_1.blinded_hops,
6824 blinding_point: blinded_path_1.blinding_point,
6825 excess_final_cltv_expiry_delta: 40,
6826 final_value_msat: 100,
6828 hops: vec![RouteHop {
6829 pubkey: ln_test_utils::pubkey(51),
6830 node_features: NodeFeatures::empty(),
6831 short_channel_id: 43,
6832 channel_features: ChannelFeatures::empty(),
6834 cltv_expiry_delta: 0,
6835 maybe_announced_channel: true,
6836 }], blinded_tail: None }],
6839 let encoded_route = route.encode();
6840 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6841 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6842 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6844 // (De)serialize a Route with two paths, each containing a blinded tail.
6845 route.paths[1].blinded_tail = Some(BlindedTail {
6846 hops: blinded_path_2.blinded_hops,
6847 blinding_point: blinded_path_2.blinding_point,
6848 excess_final_cltv_expiry_delta: 41,
6849 final_value_msat: 101,
6851 let encoded_route = route.encode();
6852 let decoded_route: Route = Readable::read(&mut Cursor::new(&encoded_route[..])).unwrap();
6853 assert_eq!(decoded_route.paths[0].blinded_tail, route.paths[0].blinded_tail);
6854 assert_eq!(decoded_route.paths[1].blinded_tail, route.paths[1].blinded_tail);
6858 fn blinded_path_inflight_processing() {
6859 // Ensure we'll score the channel that's inbound to a blinded path's introduction node, and
6860 // account for the blinded tail's final amount_msat.
6861 let mut inflight_htlcs = InFlightHtlcs::new();
6862 let blinded_path = BlindedPath {
6863 introduction_node_id: ln_test_utils::pubkey(43),
6864 blinding_point: ln_test_utils::pubkey(48),
6865 blinded_hops: vec![BlindedHop { blinded_node_id: ln_test_utils::pubkey(49), encrypted_payload: Vec::new() }],
6868 hops: vec![RouteHop {
6869 pubkey: ln_test_utils::pubkey(42),
6870 node_features: NodeFeatures::empty(),
6871 short_channel_id: 42,
6872 channel_features: ChannelFeatures::empty(),
6874 cltv_expiry_delta: 0,
6875 maybe_announced_channel: false,
6878 pubkey: blinded_path.introduction_node_id,
6879 node_features: NodeFeatures::empty(),
6880 short_channel_id: 43,
6881 channel_features: ChannelFeatures::empty(),
6883 cltv_expiry_delta: 0,
6884 maybe_announced_channel: false,
6886 blinded_tail: Some(BlindedTail {
6887 hops: blinded_path.blinded_hops,
6888 blinding_point: blinded_path.blinding_point,
6889 excess_final_cltv_expiry_delta: 0,
6890 final_value_msat: 200,
6893 inflight_htlcs.process_path(&path, ln_test_utils::pubkey(44));
6894 assert_eq!(*inflight_htlcs.0.get(&(42, true)).unwrap(), 301);
6895 assert_eq!(*inflight_htlcs.0.get(&(43, false)).unwrap(), 201);
6899 fn blinded_path_cltv_shadow_offset() {
6900 // Make sure we add a shadow offset when sending to blinded paths.
6901 let blinded_path = BlindedPath {
6902 introduction_node_id: ln_test_utils::pubkey(43),
6903 blinding_point: ln_test_utils::pubkey(44),
6905 BlindedHop { blinded_node_id: ln_test_utils::pubkey(45), encrypted_payload: Vec::new() },
6906 BlindedHop { blinded_node_id: ln_test_utils::pubkey(46), encrypted_payload: Vec::new() }
6909 let mut route = Route { paths: vec![Path {
6910 hops: vec![RouteHop {
6911 pubkey: ln_test_utils::pubkey(42),
6912 node_features: NodeFeatures::empty(),
6913 short_channel_id: 42,
6914 channel_features: ChannelFeatures::empty(),
6916 cltv_expiry_delta: 0,
6917 maybe_announced_channel: false,
6920 pubkey: blinded_path.introduction_node_id,
6921 node_features: NodeFeatures::empty(),
6922 short_channel_id: 43,
6923 channel_features: ChannelFeatures::empty(),
6925 cltv_expiry_delta: 0,
6926 maybe_announced_channel: false,
6929 blinded_tail: Some(BlindedTail {
6930 hops: blinded_path.blinded_hops,
6931 blinding_point: blinded_path.blinding_point,
6932 excess_final_cltv_expiry_delta: 0,
6933 final_value_msat: 200,
6935 }], route_params: None};
6937 let payment_params = PaymentParameters::from_node_id(ln_test_utils::pubkey(47), 18);
6938 let (_, network_graph, _, _, _) = build_line_graph();
6939 add_random_cltv_offset(&mut route, &payment_params, &network_graph.read_only(), &[0; 32]);
6940 assert_eq!(route.paths[0].blinded_tail.as_ref().unwrap().excess_final_cltv_expiry_delta, 40);
6941 assert_eq!(route.paths[0].hops.last().unwrap().cltv_expiry_delta, 40);
6945 fn simple_blinded_route_hints() {
6946 do_simple_blinded_route_hints(1);
6947 do_simple_blinded_route_hints(2);
6948 do_simple_blinded_route_hints(3);
6951 fn do_simple_blinded_route_hints(num_blinded_hops: usize) {
6952 // Check that we can generate a route to a blinded path with the expected hops.
6953 let (secp_ctx, network, _, _, logger) = build_graph();
6954 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
6955 let network_graph = network.read_only();
6957 let scorer = ln_test_utils::TestScorer::new();
6958 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
6959 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6961 let mut blinded_path = BlindedPath {
6962 introduction_node_id: nodes[2],
6963 blinding_point: ln_test_utils::pubkey(42),
6964 blinded_hops: Vec::with_capacity(num_blinded_hops),
6966 for i in 0..num_blinded_hops {
6967 blinded_path.blinded_hops.push(
6968 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 + i as u8), encrypted_payload: Vec::new() },
6971 let blinded_payinfo = BlindedPayInfo {
6973 fee_proportional_millionths: 500,
6974 htlc_minimum_msat: 1000,
6975 htlc_maximum_msat: 100_000_000,
6976 cltv_expiry_delta: 15,
6977 features: BlindedHopFeatures::empty(),
6980 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), blinded_path.clone())]);
6981 let route_params = RouteParameters::from_payment_params_and_value(
6982 payment_params, 1001);
6983 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
6984 &scorer, &Default::default(), &random_seed_bytes).unwrap();
6985 assert_eq!(route.paths.len(), 1);
6986 assert_eq!(route.paths[0].hops.len(), 2);
6988 let tail = route.paths[0].blinded_tail.as_ref().unwrap();
6989 assert_eq!(tail.hops, blinded_path.blinded_hops);
6990 assert_eq!(tail.excess_final_cltv_expiry_delta, 0);
6991 assert_eq!(tail.final_value_msat, 1001);
6993 let final_hop = route.paths[0].hops.last().unwrap();
6994 assert_eq!(final_hop.pubkey, blinded_path.introduction_node_id);
6995 if tail.hops.len() > 1 {
6996 assert_eq!(final_hop.fee_msat,
6997 blinded_payinfo.fee_base_msat as u64 + blinded_payinfo.fee_proportional_millionths as u64 * tail.final_value_msat / 1000000);
6998 assert_eq!(final_hop.cltv_expiry_delta, blinded_payinfo.cltv_expiry_delta as u32);
7000 assert_eq!(final_hop.fee_msat, 0);
7001 assert_eq!(final_hop.cltv_expiry_delta, 0);
7006 fn blinded_path_routing_errors() {
7007 // Check that we can generate a route to a blinded path with the expected hops.
7008 let (secp_ctx, network, _, _, logger) = build_graph();
7009 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7010 let network_graph = network.read_only();
7012 let scorer = ln_test_utils::TestScorer::new();
7013 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7014 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7016 let mut invalid_blinded_path = BlindedPath {
7017 introduction_node_id: nodes[2],
7018 blinding_point: ln_test_utils::pubkey(42),
7020 BlindedHop { blinded_node_id: ln_test_utils::pubkey(43), encrypted_payload: vec![0; 43] },
7023 let blinded_payinfo = BlindedPayInfo {
7025 fee_proportional_millionths: 500,
7026 htlc_minimum_msat: 1000,
7027 htlc_maximum_msat: 100_000_000,
7028 cltv_expiry_delta: 15,
7029 features: BlindedHopFeatures::empty(),
7032 let mut invalid_blinded_path_2 = invalid_blinded_path.clone();
7033 invalid_blinded_path_2.introduction_node_id = ln_test_utils::pubkey(45);
7034 let payment_params = PaymentParameters::blinded(vec![
7035 (blinded_payinfo.clone(), invalid_blinded_path.clone()),
7036 (blinded_payinfo.clone(), invalid_blinded_path_2)]);
7037 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7038 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7039 &scorer, &Default::default(), &random_seed_bytes)
7041 Err(LightningError { err, .. }) => {
7042 assert_eq!(err, "1-hop blinded paths must all have matching introduction node ids");
7044 _ => panic!("Expected error")
7047 invalid_blinded_path.introduction_node_id = our_id;
7048 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo.clone(), invalid_blinded_path.clone())]);
7049 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7050 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7051 &Default::default(), &random_seed_bytes)
7053 Err(LightningError { err, .. }) => {
7054 assert_eq!(err, "Cannot generate a route to blinded paths if we are the introduction node to all of them");
7056 _ => panic!("Expected error")
7059 invalid_blinded_path.introduction_node_id = ln_test_utils::pubkey(46);
7060 invalid_blinded_path.blinded_hops.clear();
7061 let payment_params = PaymentParameters::blinded(vec![(blinded_payinfo, invalid_blinded_path)]);
7062 let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1001);
7063 match get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger), &scorer,
7064 &Default::default(), &random_seed_bytes)
7066 Err(LightningError { err, .. }) => {
7067 assert_eq!(err, "0-hop blinded path provided");
7069 _ => panic!("Expected error")
7074 fn matching_intro_node_paths_provided() {
7075 // Check that if multiple blinded paths with the same intro node are provided in payment
7076 // parameters, we'll return the correct paths in the resulting MPP route.
7077 let (secp_ctx, network, _, _, logger) = build_graph();
7078 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7079 let network_graph = network.read_only();
7081 let scorer = ln_test_utils::TestScorer::new();
7082 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7083 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7084 let config = UserConfig::default();
7086 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7087 let blinded_path_1 = BlindedPath {
7088 introduction_node_id: nodes[2],
7089 blinding_point: ln_test_utils::pubkey(42),
7091 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7092 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7095 let blinded_payinfo_1 = BlindedPayInfo {
7097 fee_proportional_millionths: 0,
7098 htlc_minimum_msat: 0,
7099 htlc_maximum_msat: 30_000,
7100 cltv_expiry_delta: 0,
7101 features: BlindedHopFeatures::empty(),
7104 let mut blinded_path_2 = blinded_path_1.clone();
7105 blinded_path_2.blinding_point = ln_test_utils::pubkey(43);
7106 let mut blinded_payinfo_2 = blinded_payinfo_1.clone();
7107 blinded_payinfo_2.htlc_maximum_msat = 70_000;
7109 let blinded_hints = vec![
7110 (blinded_payinfo_1.clone(), blinded_path_1.clone()),
7111 (blinded_payinfo_2.clone(), blinded_path_2.clone()),
7113 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7114 .with_bolt12_features(bolt12_features.clone()).unwrap();
7116 let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 100_000);
7117 route_params.max_total_routing_fee_msat = Some(100_000);
7118 let route = get_route(&our_id, &route_params, &network_graph, None, Arc::clone(&logger),
7119 &scorer, &Default::default(), &random_seed_bytes).unwrap();
7120 assert_eq!(route.paths.len(), 2);
7121 let mut total_amount_paid_msat = 0;
7122 for path in route.paths.into_iter() {
7123 assert_eq!(path.hops.last().unwrap().pubkey, nodes[2]);
7124 if let Some(bt) = &path.blinded_tail {
7125 assert_eq!(bt.blinding_point,
7126 blinded_hints.iter().find(|(p, _)| p.htlc_maximum_msat == path.final_value_msat())
7127 .map(|(_, bp)| bp.blinding_point).unwrap());
7128 } else { panic!(); }
7129 total_amount_paid_msat += path.final_value_msat();
7131 assert_eq!(total_amount_paid_msat, 100_000);
7135 fn direct_to_intro_node() {
7136 // This previously caused a debug panic in the router when asserting
7137 // `used_liquidity_msat <= hop_max_msat`, because when adding first_hop<>blinded_route_hint
7138 // direct channels we failed to account for the fee charged for use of the blinded path.
7141 // node0 -1(1)2 - node1
7142 // such that there isn't enough liquidity to reach node1, but the router thinks there is if it
7143 // doesn't account for the blinded path fee.
7145 let secp_ctx = Secp256k1::new();
7146 let logger = Arc::new(ln_test_utils::TestLogger::new());
7147 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7148 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
7149 let scorer = ln_test_utils::TestScorer::new();
7150 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7151 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7153 let amt_msat = 10_000_000;
7154 let (_, _, privkeys, nodes) = get_nodes(&secp_ctx);
7155 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[1],
7156 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
7157 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7158 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7159 short_channel_id: 1,
7162 cltv_expiry_delta: 42,
7163 htlc_minimum_msat: 1_000,
7164 htlc_maximum_msat: 10_000_000,
7166 fee_proportional_millionths: 0,
7167 excess_data: Vec::new()
7169 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
7170 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7171 short_channel_id: 1,
7174 cltv_expiry_delta: 42,
7175 htlc_minimum_msat: 1_000,
7176 htlc_maximum_msat: 10_000_000,
7178 fee_proportional_millionths: 0,
7179 excess_data: Vec::new()
7181 let first_hops = vec![
7182 get_channel_details(Some(1), nodes[1], InitFeatures::from_le_bytes(vec![0b11]), 10_000_000)];
7184 let blinded_path = BlindedPath {
7185 introduction_node_id: nodes[1],
7186 blinding_point: ln_test_utils::pubkey(42),
7188 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7189 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7192 let blinded_payinfo = BlindedPayInfo {
7193 fee_base_msat: 1000,
7194 fee_proportional_millionths: 0,
7195 htlc_minimum_msat: 1000,
7196 htlc_maximum_msat: MAX_VALUE_MSAT,
7197 cltv_expiry_delta: 0,
7198 features: BlindedHopFeatures::empty(),
7200 let blinded_hints = vec![(blinded_payinfo.clone(), blinded_path)];
7202 let payment_params = PaymentParameters::blinded(blinded_hints.clone());
7204 let netgraph = network_graph.read_only();
7205 let route_params = RouteParameters::from_payment_params_and_value(
7206 payment_params.clone(), amt_msat);
7207 if let Err(LightningError { err, .. }) = get_route(&nodes[0], &route_params, &netgraph,
7208 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7209 &Default::default(), &random_seed_bytes) {
7210 assert_eq!(err, "Failed to find a path to the given destination");
7211 } else { panic!("Expected error") }
7213 // Sending an exact amount accounting for the blinded path fee works.
7214 let amt_minus_blinded_path_fee = amt_msat - blinded_payinfo.fee_base_msat as u64;
7215 let route_params = RouteParameters::from_payment_params_and_value(
7216 payment_params, amt_minus_blinded_path_fee);
7217 let route = get_route(&nodes[0], &route_params, &netgraph,
7218 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7219 &Default::default(), &random_seed_bytes).unwrap();
7220 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7221 assert_eq!(route.get_total_amount(), amt_minus_blinded_path_fee);
7225 fn direct_to_matching_intro_nodes() {
7226 // This previously caused us to enter `unreachable` code in the following situation:
7227 // 1. We add a route candidate for intro_node contributing a high amount
7228 // 2. We add a first_hop<>intro_node route candidate for the same high amount
7229 // 3. We see a cheaper blinded route hint for the same intro node but a much lower contribution
7230 // amount, and update our route candidate for intro_node for the lower amount
7231 // 4. We then attempt to update the aforementioned first_hop<>intro_node route candidate for the
7232 // lower contribution amount, but fail (this was previously caused by failure to account for
7233 // blinded path fees when adding first_hop<>intro_node candidates)
7234 // 5. We go to construct the path from these route candidates and our first_hop<>intro_node
7235 // candidate still thinks its path is contributing the original higher amount. This caused us
7236 // to hit an `unreachable` overflow when calculating the cheaper intro_node fees over the
7238 let secp_ctx = Secp256k1::new();
7239 let logger = Arc::new(ln_test_utils::TestLogger::new());
7240 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7241 let scorer = ln_test_utils::TestScorer::new();
7242 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7243 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7244 let config = UserConfig::default();
7246 // Values are taken from the fuzz input that uncovered this panic.
7247 let amt_msat = 21_7020_5185_1403_2640;
7248 let (_, _, _, nodes) = get_nodes(&secp_ctx);
7249 let first_hops = vec![
7250 get_channel_details(Some(1), nodes[1], channelmanager::provided_init_features(&config),
7251 18446744073709551615)];
7253 let blinded_path = BlindedPath {
7254 introduction_node_id: nodes[1],
7255 blinding_point: ln_test_utils::pubkey(42),
7257 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7258 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7261 let blinded_payinfo = BlindedPayInfo {
7262 fee_base_msat: 5046_2720,
7263 fee_proportional_millionths: 0,
7264 htlc_minimum_msat: 4503_5996_2737_0496,
7265 htlc_maximum_msat: 45_0359_9627_3704_9600,
7266 cltv_expiry_delta: 0,
7267 features: BlindedHopFeatures::empty(),
7269 let mut blinded_hints = vec![
7270 (blinded_payinfo.clone(), blinded_path.clone()),
7271 (blinded_payinfo.clone(), blinded_path.clone()),
7273 blinded_hints[1].0.fee_base_msat = 419_4304;
7274 blinded_hints[1].0.fee_proportional_millionths = 257;
7275 blinded_hints[1].0.htlc_minimum_msat = 280_8908_6115_8400;
7276 blinded_hints[1].0.htlc_maximum_msat = 2_8089_0861_1584_0000;
7277 blinded_hints[1].0.cltv_expiry_delta = 0;
7279 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7280 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7281 .with_bolt12_features(bolt12_features.clone()).unwrap();
7283 let netgraph = network_graph.read_only();
7284 let route_params = RouteParameters::from_payment_params_and_value(
7285 payment_params, amt_msat);
7286 let route = get_route(&nodes[0], &route_params, &netgraph,
7287 Some(&first_hops.iter().collect::<Vec<_>>()), Arc::clone(&logger), &scorer,
7288 &Default::default(), &random_seed_bytes).unwrap();
7289 assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64);
7290 assert_eq!(route.get_total_amount(), amt_msat);
7294 fn we_are_intro_node_candidate_hops() {
7295 // This previously led to a panic in the router because we'd generate a Path with only a
7296 // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints
7297 // where the origin node is the intro node. We now fully disallow considering candidate hops
7298 // where the origin node is the intro node.
7299 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7300 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7301 let scorer = ln_test_utils::TestScorer::new();
7302 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7303 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7304 let config = UserConfig::default();
7306 // Values are taken from the fuzz input that uncovered this panic.
7307 let amt_msat = 21_7020_5185_1423_0019;
7309 let blinded_path = BlindedPath {
7310 introduction_node_id: our_id,
7311 blinding_point: ln_test_utils::pubkey(42),
7313 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7314 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7317 let blinded_payinfo = BlindedPayInfo {
7318 fee_base_msat: 5052_9027,
7319 fee_proportional_millionths: 0,
7320 htlc_minimum_msat: 21_7020_5185_1423_0019,
7321 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7322 cltv_expiry_delta: 0,
7323 features: BlindedHopFeatures::empty(),
7325 let mut blinded_hints = vec![
7326 (blinded_payinfo.clone(), blinded_path.clone()),
7327 (blinded_payinfo.clone(), blinded_path.clone()),
7329 blinded_hints[1].1.introduction_node_id = nodes[6];
7331 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7332 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7333 .with_bolt12_features(bolt12_features.clone()).unwrap();
7335 let netgraph = network_graph.read_only();
7336 let route_params = RouteParameters::from_payment_params_and_value(
7337 payment_params, amt_msat);
7338 if let Err(LightningError { err, .. }) = get_route(
7339 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7341 assert_eq!(err, "Failed to find a path to the given destination");
7346 fn we_are_intro_node_bp_in_final_path_fee_calc() {
7347 // This previously led to a debug panic in the router because we'd find an invalid Path with
7348 // 0 unblinded hops and a blinded tail, leading to the generation of a final
7349 // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of
7350 // the payment, when it was intended to only include the final value of the payment.
7351 let (secp_ctx, network_graph, _, _, logger) = build_graph();
7352 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7353 let scorer = ln_test_utils::TestScorer::new();
7354 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7355 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7356 let config = UserConfig::default();
7358 // Values are taken from the fuzz input that uncovered this panic.
7359 let amt_msat = 21_7020_5185_1423_0019;
7361 let blinded_path = BlindedPath {
7362 introduction_node_id: our_id,
7363 blinding_point: ln_test_utils::pubkey(42),
7365 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7366 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7369 let blinded_payinfo = BlindedPayInfo {
7370 fee_base_msat: 10_4425_1395,
7371 fee_proportional_millionths: 0,
7372 htlc_minimum_msat: 21_7301_9934_9094_0931,
7373 htlc_maximum_msat: 1844_6744_0737_0955_1615,
7374 cltv_expiry_delta: 0,
7375 features: BlindedHopFeatures::empty(),
7377 let mut blinded_hints = vec![
7378 (blinded_payinfo.clone(), blinded_path.clone()),
7379 (blinded_payinfo.clone(), blinded_path.clone()),
7380 (blinded_payinfo.clone(), blinded_path.clone()),
7382 blinded_hints[1].0.fee_base_msat = 5052_9027;
7383 blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019;
7384 blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615;
7386 blinded_hints[2].1.introduction_node_id = nodes[6];
7388 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7389 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7390 .with_bolt12_features(bolt12_features.clone()).unwrap();
7392 let netgraph = network_graph.read_only();
7393 let route_params = RouteParameters::from_payment_params_and_value(
7394 payment_params, amt_msat);
7395 if let Err(LightningError { err, .. }) = get_route(
7396 &our_id, &route_params, &netgraph, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7398 assert_eq!(err, "Failed to find a path to the given destination");
7403 fn min_htlc_overpay_violates_max_htlc() {
7404 do_min_htlc_overpay_violates_max_htlc(true);
7405 do_min_htlc_overpay_violates_max_htlc(false);
7407 fn do_min_htlc_overpay_violates_max_htlc(blinded_payee: bool) {
7408 // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
7409 // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
7410 // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
7411 // that the used liquidity for a hop was less than its available liquidity limit.
7412 let secp_ctx = Secp256k1::new();
7413 let logger = Arc::new(ln_test_utils::TestLogger::new());
7414 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7415 let scorer = ln_test_utils::TestScorer::new();
7416 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7417 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7418 let config = UserConfig::default();
7420 // Values are taken from the fuzz input that uncovered this panic.
7421 let amt_msat = 7_4009_8048;
7422 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7423 let first_hop_outbound_capacity = 2_7345_2000;
7424 let first_hops = vec![get_channel_details(
7425 Some(200), nodes[0], channelmanager::provided_init_features(&config),
7426 first_hop_outbound_capacity
7429 let base_fee = 1_6778_3453;
7430 let htlc_min = 2_5165_8240;
7431 let payment_params = if blinded_payee {
7432 let blinded_path = BlindedPath {
7433 introduction_node_id: nodes[0],
7434 blinding_point: ln_test_utils::pubkey(42),
7436 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7437 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7440 let blinded_payinfo = BlindedPayInfo {
7441 fee_base_msat: base_fee,
7442 fee_proportional_millionths: 0,
7443 htlc_minimum_msat: htlc_min,
7444 htlc_maximum_msat: htlc_min * 1000,
7445 cltv_expiry_delta: 0,
7446 features: BlindedHopFeatures::empty(),
7448 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7449 PaymentParameters::blinded(vec![(blinded_payinfo, blinded_path)])
7450 .with_bolt12_features(bolt12_features.clone()).unwrap()
7452 let route_hint = RouteHint(vec![RouteHintHop {
7453 src_node_id: nodes[0],
7454 short_channel_id: 42,
7456 base_msat: base_fee,
7457 proportional_millionths: 0,
7459 cltv_expiry_delta: 10,
7460 htlc_minimum_msat: Some(htlc_min),
7461 htlc_maximum_msat: None,
7464 PaymentParameters::from_node_id(nodes[1], 42)
7465 .with_route_hints(vec![route_hint]).unwrap()
7466 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7469 let netgraph = network_graph.read_only();
7470 let route_params = RouteParameters::from_payment_params_and_value(
7471 payment_params, amt_msat);
7472 if let Err(LightningError { err, .. }) = get_route(
7473 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7474 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7476 assert_eq!(err, "Failed to find a path to the given destination");
7481 fn previously_used_liquidity_violates_max_htlc() {
7482 do_previously_used_liquidity_violates_max_htlc(true);
7483 do_previously_used_liquidity_violates_max_htlc(false);
7486 fn do_previously_used_liquidity_violates_max_htlc(blinded_payee: bool) {
7487 // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
7488 // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
7489 // candidate. In this case, the candidate does not have enough due to a previous path taking up
7490 // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
7491 // asserting that the used liquidity for a hop was less than its available liquidity limit.
7492 let secp_ctx = Secp256k1::new();
7493 let logger = Arc::new(ln_test_utils::TestLogger::new());
7494 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7495 let scorer = ln_test_utils::TestScorer::new();
7496 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7497 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7498 let config = UserConfig::default();
7500 // Values are taken from the fuzz input that uncovered this panic.
7501 let amt_msat = 52_4288;
7502 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7503 let first_hops = vec![get_channel_details(
7504 Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
7505 ), get_channel_details(
7506 Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
7509 let base_fees = [0, 425_9840, 0, 0];
7510 let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
7511 let payment_params = if blinded_payee {
7512 let blinded_path = BlindedPath {
7513 introduction_node_id: nodes[0],
7514 blinding_point: ln_test_utils::pubkey(42),
7516 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7517 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7520 let mut blinded_hints = Vec::new();
7521 for (base_fee, htlc_min) in base_fees.iter().zip(htlc_mins.iter()) {
7522 blinded_hints.push((BlindedPayInfo {
7523 fee_base_msat: *base_fee,
7524 fee_proportional_millionths: 0,
7525 htlc_minimum_msat: *htlc_min,
7526 htlc_maximum_msat: htlc_min * 100,
7527 cltv_expiry_delta: 10,
7528 features: BlindedHopFeatures::empty(),
7529 }, blinded_path.clone()));
7531 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7532 PaymentParameters::blinded(blinded_hints.clone())
7533 .with_bolt12_features(bolt12_features.clone()).unwrap()
7535 let mut route_hints = Vec::new();
7536 for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
7537 route_hints.push(RouteHint(vec![RouteHintHop {
7538 src_node_id: nodes[0],
7539 short_channel_id: 42 + idx as u64,
7541 base_msat: *base_fee,
7542 proportional_millionths: 0,
7544 cltv_expiry_delta: 10,
7545 htlc_minimum_msat: Some(*htlc_min),
7546 htlc_maximum_msat: Some(htlc_min * 100),
7549 PaymentParameters::from_node_id(nodes[1], 42)
7550 .with_route_hints(route_hints).unwrap()
7551 .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
7554 let netgraph = network_graph.read_only();
7555 let route_params = RouteParameters::from_payment_params_and_value(
7556 payment_params, amt_msat);
7558 let route = get_route(
7559 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7560 Arc::clone(&logger), &scorer, &(), &random_seed_bytes
7562 assert_eq!(route.paths.len(), 1);
7563 assert_eq!(route.get_total_amount(), amt_msat);
7567 fn candidate_path_min() {
7568 // Test that if a candidate first_hop<>network_node channel does not have enough contribution
7569 // amount to cover the next channel's min htlc plus fees, we will not consider that candidate.
7570 // Previously, we were storing RouteGraphNodes with a path_min that did not include fees, and
7571 // would add a connecting first_hop node that did not have enough contribution amount, leading
7572 // to a debug panic upon invalid path construction.
7573 let secp_ctx = Secp256k1::new();
7574 let logger = Arc::new(ln_test_utils::TestLogger::new());
7575 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7576 let gossip_sync = P2PGossipSync::new(network_graph.clone(), None, logger.clone());
7577 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7578 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7579 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7580 let config = UserConfig::default();
7582 // Values are taken from the fuzz input that uncovered this panic.
7583 let amt_msat = 7_4009_8048;
7584 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
7585 let first_hops = vec![get_channel_details(
7586 Some(200), nodes[0], channelmanager::provided_init_features(&config), 2_7345_2000
7589 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
7590 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
7591 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
7592 short_channel_id: 6,
7595 cltv_expiry_delta: (6 << 4) | 0,
7596 htlc_minimum_msat: 0,
7597 htlc_maximum_msat: MAX_VALUE_MSAT,
7599 fee_proportional_millionths: 0,
7600 excess_data: Vec::new()
7602 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
7604 let htlc_min = 2_5165_8240;
7605 let blinded_hints = vec![
7607 fee_base_msat: 1_6778_3453,
7608 fee_proportional_millionths: 0,
7609 htlc_minimum_msat: htlc_min,
7610 htlc_maximum_msat: htlc_min * 100,
7611 cltv_expiry_delta: 10,
7612 features: BlindedHopFeatures::empty(),
7614 introduction_node_id: nodes[0],
7615 blinding_point: ln_test_utils::pubkey(42),
7617 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7618 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7622 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7623 let payment_params = PaymentParameters::blinded(blinded_hints.clone())
7624 .with_bolt12_features(bolt12_features.clone()).unwrap();
7625 let route_params = RouteParameters::from_payment_params_and_value(
7626 payment_params, amt_msat);
7627 let netgraph = network_graph.read_only();
7629 if let Err(LightningError { err, .. }) = get_route(
7630 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7631 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7634 assert_eq!(err, "Failed to find a path to the given destination");
7639 fn path_contribution_includes_min_htlc_overpay() {
7640 // Previously, the fuzzer hit a debug panic because we wouldn't include the amount overpaid to
7641 // meet a last hop's min_htlc in the total collected paths value. We now include this value and
7642 // also penalize hops along the overpaying path to ensure that it gets deprioritized in path
7643 // selection, both tested here.
7644 let secp_ctx = Secp256k1::new();
7645 let logger = Arc::new(ln_test_utils::TestLogger::new());
7646 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
7647 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), network_graph.clone(), logger.clone());
7648 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
7649 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7650 let config = UserConfig::default();
7652 // Values are taken from the fuzz input that uncovered this panic.
7653 let amt_msat = 562_0000;
7654 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
7655 let first_hops = vec![
7656 get_channel_details(
7657 Some(83), nodes[0], channelmanager::provided_init_features(&config), 2199_0000,
7661 let htlc_mins = [49_0000, 1125_0000];
7662 let payment_params = {
7663 let blinded_path = BlindedPath {
7664 introduction_node_id: nodes[0],
7665 blinding_point: ln_test_utils::pubkey(42),
7667 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() },
7668 BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }
7671 let mut blinded_hints = Vec::new();
7672 for htlc_min in htlc_mins.iter() {
7673 blinded_hints.push((BlindedPayInfo {
7675 fee_proportional_millionths: 0,
7676 htlc_minimum_msat: *htlc_min,
7677 htlc_maximum_msat: *htlc_min * 100,
7678 cltv_expiry_delta: 10,
7679 features: BlindedHopFeatures::empty(),
7680 }, blinded_path.clone()));
7682 let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context();
7683 PaymentParameters::blinded(blinded_hints.clone())
7684 .with_bolt12_features(bolt12_features.clone()).unwrap()
7687 let netgraph = network_graph.read_only();
7688 let route_params = RouteParameters::from_payment_params_and_value(
7689 payment_params, amt_msat);
7690 let route = get_route(
7691 &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
7692 Arc::clone(&logger), &scorer, &ProbabilisticScoringFeeParameters::default(),
7695 assert_eq!(route.paths.len(), 1);
7696 assert_eq!(route.get_total_amount(), amt_msat);
7700 #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]
7701 pub(crate) mod bench_utils {
7705 use bitcoin::hashes::Hash;
7706 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
7708 use crate::chain::transaction::OutPoint;
7709 use crate::routing::scoring::ScoreUpdate;
7710 use crate::sign::{EntropySource, KeysManager};
7711 use crate::ln::ChannelId;
7712 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
7713 use crate::ln::features::Bolt11InvoiceFeatures;
7714 use crate::routing::gossip::NetworkGraph;
7715 use crate::util::config::UserConfig;
7716 use crate::util::ser::ReadableArgs;
7717 use crate::util::test_utils::TestLogger;
7719 /// Tries to open a network graph file, or panics with a URL to fetch it.
7720 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
7721 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
7722 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
7723 .or_else(|_| { // Fall back to guessing based on the binary location
7724 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
7725 let mut path = std::env::current_exe().unwrap();
7726 path.pop(); // lightning-...
7728 path.pop(); // debug
7729 path.pop(); // target
7730 path.push("lightning");
7731 path.push("net_graph-2023-01-18.bin");
7734 .or_else(|_| { // Fall back to guessing based on the binary location for a subcrate
7735 // path is likely something like .../rust-lightning/bench/target/debug/deps/bench..
7736 let mut path = std::env::current_exe().unwrap();
7737 path.pop(); // bench...
7739 path.pop(); // debug
7740 path.pop(); // target
7741 path.pop(); // bench
7742 path.push("lightning");
7743 path.push("net_graph-2023-01-18.bin");
7746 .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");
7747 #[cfg(require_route_graph_test)]
7748 return Ok(res.unwrap());
7749 #[cfg(not(require_route_graph_test))]
7753 pub(crate) fn read_network_graph(logger: &TestLogger) -> Result<NetworkGraph<&TestLogger>, &'static str> {
7754 get_route_file().map(|mut f| NetworkGraph::read(&mut f, logger).unwrap())
7757 pub(crate) fn payer_pubkey() -> PublicKey {
7758 let secp_ctx = Secp256k1::new();
7759 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
7763 pub(crate) fn first_hop(node_id: PublicKey) -> ChannelDetails {
7765 channel_id: ChannelId::new_zero(),
7766 counterparty: ChannelCounterparty {
7767 features: channelmanager::provided_init_features(&UserConfig::default()),
7769 unspendable_punishment_reserve: 0,
7770 forwarding_info: None,
7771 outbound_htlc_minimum_msat: None,
7772 outbound_htlc_maximum_msat: None,
7774 funding_txo: Some(OutPoint {
7775 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
7778 short_channel_id: Some(1),
7779 inbound_scid_alias: None,
7780 outbound_scid_alias: None,
7781 channel_value_satoshis: 10_000_000_000,
7783 outbound_capacity_msat: 10_000_000_000,
7784 next_outbound_htlc_minimum_msat: 0,
7785 next_outbound_htlc_limit_msat: 10_000_000_000,
7786 inbound_capacity_msat: 0,
7787 unspendable_punishment_reserve: None,
7788 confirmations_required: None,
7789 confirmations: None,
7790 force_close_spend_delay: None,
7792 is_channel_ready: true,
7795 inbound_htlc_minimum_msat: None,
7796 inbound_htlc_maximum_msat: None,
7798 feerate_sat_per_1000_weight: None,
7799 channel_shutdown_state: Some(channelmanager::ChannelShutdownState::NotShuttingDown),
7803 pub(crate) fn generate_test_routes<S: ScoreLookUp + ScoreUpdate>(graph: &NetworkGraph<&TestLogger>, scorer: &mut S,
7804 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, mut seed: u64,
7805 starting_amount: u64, route_count: usize,
7806 ) -> Vec<(ChannelDetails, PaymentParameters, u64)> {
7807 let payer = payer_pubkey();
7808 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7809 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7811 let nodes = graph.read_only().nodes().clone();
7812 let mut route_endpoints = Vec::new();
7813 // Fetch 1.5x more routes than we need as after we do some scorer updates we may end up
7814 // with some routes we picked being un-routable.
7815 for _ in 0..route_count * 3 / 2 {
7817 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7818 let src = PublicKey::from_slice(nodes.unordered_keys()
7819 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7820 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7821 let dst = PublicKey::from_slice(nodes.unordered_keys()
7822 .skip((seed as usize) % nodes.len()).next().unwrap().as_slice()).unwrap();
7823 let params = PaymentParameters::from_node_id(dst, 42)
7824 .with_bolt11_features(features.clone()).unwrap();
7825 let first_hop = first_hop(src);
7826 let amt_msat = starting_amount + seed % 1_000_000;
7827 let route_params = RouteParameters::from_payment_params_and_value(
7828 params.clone(), amt_msat);
7830 get_route(&payer, &route_params, &graph.read_only(), Some(&[&first_hop]),
7831 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok();
7833 // ...and seed the scorer with success and failure data...
7834 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7835 let mut score_amt = seed % 1_000_000_000;
7837 // Generate fail/success paths for a wider range of potential amounts with
7838 // MPP enabled to give us a chance to apply penalties for more potential
7840 let mpp_features = channelmanager::provided_invoice_features(&UserConfig::default());
7841 let params = PaymentParameters::from_node_id(dst, 42)
7842 .with_bolt11_features(mpp_features).unwrap();
7843 let route_params = RouteParameters::from_payment_params_and_value(
7844 params.clone(), score_amt);
7845 let route_res = get_route(&payer, &route_params, &graph.read_only(),
7846 Some(&[&first_hop]), &TestLogger::new(), scorer, score_params,
7847 &random_seed_bytes);
7848 if let Ok(route) = route_res {
7849 for path in route.paths {
7850 if seed & 0x80 == 0 {
7851 scorer.payment_path_successful(&path);
7853 let short_channel_id = path.hops[path.hops.len() / 2].short_channel_id;
7854 scorer.payment_path_failed(&path, short_channel_id);
7856 seed = seed.overflowing_mul(6364136223846793005).0.overflowing_add(1).0;
7860 // If we couldn't find a path with a higer amount, reduce and try again.
7864 route_endpoints.push((first_hop, params, amt_msat));
7870 // Because we've changed channel scores, it's possible we'll take different routes to the
7871 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
7872 // requires a too-high CLTV delta.
7873 route_endpoints.retain(|(first_hop, params, amt_msat)| {
7874 let route_params = RouteParameters::from_payment_params_and_value(
7875 params.clone(), *amt_msat);
7876 get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
7877 &TestLogger::new(), scorer, score_params, &random_seed_bytes).is_ok()
7879 route_endpoints.truncate(route_count);
7880 assert_eq!(route_endpoints.len(), route_count);
7888 use crate::routing::scoring::{ScoreUpdate, ScoreLookUp};
7889 use crate::sign::{EntropySource, KeysManager};
7890 use crate::ln::channelmanager;
7891 use crate::ln::features::Bolt11InvoiceFeatures;
7892 use crate::routing::gossip::NetworkGraph;
7893 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringFeeParameters, ProbabilisticScoringDecayParameters};
7894 use crate::util::config::UserConfig;
7895 use crate::util::logger::{Logger, Record};
7896 use crate::util::test_utils::TestLogger;
7898 use criterion::Criterion;
7900 struct DummyLogger {}
7901 impl Logger for DummyLogger {
7902 fn log(&self, _record: &Record) {}
7905 pub fn generate_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7906 let logger = TestLogger::new();
7907 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7908 let scorer = FixedPenaltyScorer::with_penalty(0);
7909 generate_routes(bench, &network_graph, scorer, &Default::default(),
7910 Bolt11InvoiceFeatures::empty(), 0, "generate_routes_with_zero_penalty_scorer");
7913 pub fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Criterion) {
7914 let logger = TestLogger::new();
7915 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7916 let scorer = FixedPenaltyScorer::with_penalty(0);
7917 generate_routes(bench, &network_graph, scorer, &Default::default(),
7918 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7919 "generate_mpp_routes_with_zero_penalty_scorer");
7922 pub fn generate_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7923 let logger = TestLogger::new();
7924 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7925 let params = ProbabilisticScoringFeeParameters::default();
7926 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7927 generate_routes(bench, &network_graph, scorer, ¶ms, Bolt11InvoiceFeatures::empty(), 0,
7928 "generate_routes_with_probabilistic_scorer");
7931 pub fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7932 let logger = TestLogger::new();
7933 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7934 let params = ProbabilisticScoringFeeParameters::default();
7935 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7936 generate_routes(bench, &network_graph, scorer, ¶ms,
7937 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7938 "generate_mpp_routes_with_probabilistic_scorer");
7941 pub fn generate_large_mpp_routes_with_probabilistic_scorer(bench: &mut Criterion) {
7942 let logger = TestLogger::new();
7943 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7944 let params = ProbabilisticScoringFeeParameters::default();
7945 let scorer = ProbabilisticScorer::new(ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7946 generate_routes(bench, &network_graph, scorer, ¶ms,
7947 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7948 "generate_large_mpp_routes_with_probabilistic_scorer");
7951 pub fn generate_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7952 let logger = TestLogger::new();
7953 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7954 let mut params = ProbabilisticScoringFeeParameters::default();
7955 params.linear_success_probability = false;
7956 let scorer = ProbabilisticScorer::new(
7957 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7958 generate_routes(bench, &network_graph, scorer, ¶ms,
7959 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7960 "generate_routes_with_nonlinear_probabilistic_scorer");
7963 pub fn generate_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7964 let logger = TestLogger::new();
7965 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7966 let mut params = ProbabilisticScoringFeeParameters::default();
7967 params.linear_success_probability = false;
7968 let scorer = ProbabilisticScorer::new(
7969 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7970 generate_routes(bench, &network_graph, scorer, ¶ms,
7971 channelmanager::provided_invoice_features(&UserConfig::default()), 0,
7972 "generate_mpp_routes_with_nonlinear_probabilistic_scorer");
7975 pub fn generate_large_mpp_routes_with_nonlinear_probabilistic_scorer(bench: &mut Criterion) {
7976 let logger = TestLogger::new();
7977 let network_graph = bench_utils::read_network_graph(&logger).unwrap();
7978 let mut params = ProbabilisticScoringFeeParameters::default();
7979 params.linear_success_probability = false;
7980 let scorer = ProbabilisticScorer::new(
7981 ProbabilisticScoringDecayParameters::default(), &network_graph, &logger);
7982 generate_routes(bench, &network_graph, scorer, ¶ms,
7983 channelmanager::provided_invoice_features(&UserConfig::default()), 100_000_000,
7984 "generate_large_mpp_routes_with_nonlinear_probabilistic_scorer");
7987 fn generate_routes<S: ScoreLookUp + ScoreUpdate>(
7988 bench: &mut Criterion, graph: &NetworkGraph<&TestLogger>, mut scorer: S,
7989 score_params: &S::ScoreParams, features: Bolt11InvoiceFeatures, starting_amount: u64,
7990 bench_name: &'static str,
7992 let payer = bench_utils::payer_pubkey();
7993 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
7994 let random_seed_bytes = keys_manager.get_secure_random_bytes();
7996 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
7997 let route_endpoints = bench_utils::generate_test_routes(graph, &mut scorer, score_params, features, 0xdeadbeef, starting_amount, 50);
7999 // ...then benchmark finding paths between the nodes we learned.
8001 bench.bench_function(bench_name, |b| b.iter(|| {
8002 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
8003 let route_params = RouteParameters::from_payment_params_and_value(params.clone(), *amt);
8004 assert!(get_route(&payer, &route_params, &graph.read_only(), Some(&[first_hop]),
8005 &DummyLogger{}, &scorer, score_params, &random_seed_bytes).is_ok());