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 top-level routing/network map tracking logic lives here.
12 //! You probably want to create a P2PGossipSync and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
15 use bitcoin::secp256k1::PublicKey;
16 use bitcoin::hashes::Hash;
17 use bitcoin::hashes::sha256::Hash as Sha256;
19 use crate::ln::PaymentHash;
20 use crate::ln::channelmanager::{ChannelDetails, PaymentId};
21 use crate::ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
22 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
23 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
24 use crate::routing::scoring::{ChannelUsage, LockableScore, Score};
25 use crate::util::ser::{Writeable, Readable, Writer};
26 use crate::util::logger::{Level, Logger};
27 use crate::util::chacha20::ChaCha20;
30 use crate::prelude::*;
31 use crate::sync::Mutex;
32 use alloc::collections::BinaryHeap;
36 /// A [`Router`] implemented using [`find_route`].
37 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> where
39 S::Target: for <'a> LockableScore<'a>,
43 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> DefaultRouter<G, L, S> where
49 S::Target: for <'a> LockableScore<'a>,
51 /// Creates a new router.
52 pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S) -> Self {
53 let random_seed_bytes = Mutex::new(random_seed_bytes);
54 Self { network_graph, logger, random_seed_bytes, scorer }
58 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> Router for DefaultRouter<G, L, S> where
60 S::Target: for <'a> LockableScore<'a>,
63 &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]>,
64 inflight_htlcs: &InFlightHtlcs
65 ) -> Result<Route, LightningError> {
66 let random_seed_bytes = {
67 let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
68 *locked_random_seed_bytes = Sha256::hash(&*locked_random_seed_bytes).into_inner();
69 *locked_random_seed_bytes
73 payer, params, &self.network_graph, first_hops, &*self.logger,
74 &ScorerAccountingForInFlightHtlcs::new(self.scorer.lock(), inflight_htlcs),
79 fn notify_payment_path_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
80 self.scorer.lock().payment_path_failed(path, short_channel_id);
83 fn notify_payment_path_successful(&self, path: &[&RouteHop]) {
84 self.scorer.lock().payment_path_successful(path);
87 fn notify_payment_probe_successful(&self, path: &[&RouteHop]) {
88 self.scorer.lock().probe_successful(path);
91 fn notify_payment_probe_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
92 self.scorer.lock().probe_failed(path, short_channel_id);
96 /// A trait defining behavior for routing a payment.
98 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values.
100 &self, payer: &PublicKey, route_params: &RouteParameters,
101 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: &InFlightHtlcs
102 ) -> Result<Route, LightningError>;
103 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values. Includes
104 /// `PaymentHash` and `PaymentId` to be able to correlate the request with a specific payment.
105 fn find_route_with_id(
106 &self, payer: &PublicKey, route_params: &RouteParameters,
107 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: &InFlightHtlcs,
108 _payment_hash: PaymentHash, _payment_id: PaymentId
109 ) -> Result<Route, LightningError> {
110 self.find_route(payer, route_params, first_hops, inflight_htlcs)
112 /// Lets the router know that payment through a specific path has failed.
113 fn notify_payment_path_failed(&self, path: &[&RouteHop], short_channel_id: u64);
114 /// Lets the router know that payment through a specific path was successful.
115 fn notify_payment_path_successful(&self, path: &[&RouteHop]);
116 /// Lets the router know that a payment probe was successful.
117 fn notify_payment_probe_successful(&self, path: &[&RouteHop]);
118 /// Lets the router know that a payment probe failed.
119 fn notify_payment_probe_failed(&self, path: &[&RouteHop], short_channel_id: u64);
122 /// [`Score`] implementation that factors in in-flight HTLC liquidity.
124 /// Useful for custom [`Router`] implementations to wrap their [`Score`] on-the-fly when calling
127 /// [`Score`]: crate::routing::scoring::Score
128 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Score> {
130 // Maps a channel's short channel id and its direction to the liquidity used up.
131 inflight_htlcs: &'a InFlightHtlcs,
134 impl<'a, S: Score> ScorerAccountingForInFlightHtlcs<'a, S> {
135 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
136 pub fn new(scorer: S, inflight_htlcs: &'a InFlightHtlcs) -> Self {
137 ScorerAccountingForInFlightHtlcs {
145 impl<'a, S: Score> Writeable for ScorerAccountingForInFlightHtlcs<'a, S> {
146 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
149 impl<'a, S: Score> Score for ScorerAccountingForInFlightHtlcs<'a, S> {
150 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage) -> u64 {
151 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
152 source, target, short_channel_id
154 let usage = ChannelUsage {
155 inflight_htlc_msat: usage.inflight_htlc_msat + used_liquidity,
159 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
161 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
165 fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
166 self.scorer.payment_path_failed(path, short_channel_id)
169 fn payment_path_successful(&mut self, path: &[&RouteHop]) {
170 self.scorer.payment_path_successful(path)
173 fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
174 self.scorer.probe_failed(path, short_channel_id)
177 fn probe_successful(&mut self, path: &[&RouteHop]) {
178 self.scorer.probe_successful(path)
182 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
183 /// in-use channel liquidity.
185 pub struct InFlightHtlcs(
186 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
187 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
188 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
190 HashMap<(u64, bool), u64>
194 /// Constructs an empty `InFlightHtlcs`.
195 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
197 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
198 pub fn process_path(&mut self, path: &[RouteHop], payer_node_id: PublicKey) {
199 if path.is_empty() { return };
200 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
201 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
202 // the router excludes the payer node. In the following lines, the payer's information is
203 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
204 // in our sliding window of two.
205 let reversed_hops_with_payer = path.iter().rev().skip(1)
206 .map(|hop| hop.pubkey)
207 .chain(core::iter::once(payer_node_id));
208 let mut cumulative_msat = 0;
210 // Taking the reversed vector from above, we zip it with just the reversed hops list to
211 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
212 // the total amount sent.
213 for (next_hop, prev_hop) in path.iter().rev().zip(reversed_hops_with_payer) {
214 cumulative_msat += next_hop.fee_msat;
216 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
217 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
218 .or_insert(cumulative_msat);
222 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
224 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
225 self.0.get(&(channel_scid, source < target)).map(|v| *v)
229 impl Writeable for InFlightHtlcs {
230 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
233 impl Readable for InFlightHtlcs {
234 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
235 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
236 Ok(Self(infight_map))
241 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
242 pub struct RouteHop {
243 /// The node_id of the node at this hop.
244 pub pubkey: PublicKey,
245 /// The node_announcement features of the node at this hop. For the last hop, these may be
246 /// amended to match the features present in the invoice this node generated.
247 pub node_features: NodeFeatures,
248 /// The channel that should be used from the previous hop to reach this node.
249 pub short_channel_id: u64,
250 /// The channel_announcement features of the channel that should be used from the previous hop
251 /// to reach this node.
252 pub channel_features: ChannelFeatures,
253 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
254 /// For the last hop, this should be the full value of the payment (might be more than
255 /// requested if we had to match htlc_minimum_msat).
257 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
258 /// expected at the destination, in excess of the current block height.
259 pub cltv_expiry_delta: u32,
262 impl_writeable_tlv_based!(RouteHop, {
263 (0, pubkey, required),
264 (2, node_features, required),
265 (4, short_channel_id, required),
266 (6, channel_features, required),
267 (8, fee_msat, required),
268 (10, cltv_expiry_delta, required),
271 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
272 /// it can take multiple paths. Each path is composed of one or more hops through the network.
273 #[derive(Clone, Hash, PartialEq, Eq)]
275 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
276 /// last RouteHop in each path must be the same. Each entry represents a list of hops, NOT
277 /// INCLUDING our own, where the last hop is the destination. Thus, this must always be at
278 /// least length one. While the maximum length of any given path is variable, keeping the length
279 /// of any path less or equal to 19 should currently ensure it is viable.
280 pub paths: Vec<Vec<RouteHop>>,
281 /// The `payment_params` parameter passed to [`find_route`].
282 /// This is used by `ChannelManager` to track information which may be required for retries,
283 /// provided back to you via [`Event::PaymentPathFailed`].
285 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
286 pub payment_params: Option<PaymentParameters>,
289 pub(crate) trait RoutePath {
290 /// Gets the fees for a given path, excluding any excess paid to the recipient.
291 fn get_path_fees(&self) -> u64;
293 impl RoutePath for Vec<RouteHop> {
294 fn get_path_fees(&self) -> u64 {
295 // Do not count last hop of each path since that's the full value of the payment
296 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
297 .iter().map(|hop| &hop.fee_msat)
303 /// Returns the total amount of fees paid on this [`Route`].
305 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
306 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
307 pub fn get_total_fees(&self) -> u64 {
308 self.paths.iter().map(|path| path.get_path_fees()).sum()
311 /// Returns the total amount paid on this [`Route`], excluding the fees.
312 pub fn get_total_amount(&self) -> u64 {
313 return self.paths.iter()
314 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
319 const SERIALIZATION_VERSION: u8 = 1;
320 const MIN_SERIALIZATION_VERSION: u8 = 1;
322 impl Writeable for Route {
323 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
324 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
325 (self.paths.len() as u64).write(writer)?;
326 for hops in self.paths.iter() {
327 (hops.len() as u8).write(writer)?;
328 for hop in hops.iter() {
332 write_tlv_fields!(writer, {
333 (1, self.payment_params, option),
339 impl Readable for Route {
340 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
341 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
342 let path_count: u64 = Readable::read(reader)?;
343 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
344 for _ in 0..path_count {
345 let hop_count: u8 = Readable::read(reader)?;
346 let mut hops = Vec::with_capacity(hop_count as usize);
347 for _ in 0..hop_count {
348 hops.push(Readable::read(reader)?);
352 let mut payment_params = None;
353 read_tlv_fields!(reader, {
354 (1, payment_params, option),
356 Ok(Route { paths, payment_params })
360 /// Parameters needed to find a [`Route`].
362 /// Passed to [`find_route`] and [`build_route_from_hops`], but also provided in
363 /// [`Event::PaymentPathFailed`] for retrying a failed payment path.
365 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
366 #[derive(Clone, Debug)]
367 pub struct RouteParameters {
368 /// The parameters of the failed payment path.
369 pub payment_params: PaymentParameters,
371 /// The amount in msats sent on the failed payment path.
372 pub final_value_msat: u64,
374 /// The CLTV on the final hop of the failed payment path.
375 pub final_cltv_expiry_delta: u32,
378 impl_writeable_tlv_based!(RouteParameters, {
379 (0, payment_params, required),
380 (2, final_value_msat, required),
381 (4, final_cltv_expiry_delta, required),
384 /// Maximum total CTLV difference we allow for a full payment path.
385 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
387 /// Maximum number of paths we allow an (MPP) payment to have.
388 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
389 // limits, but for now more than 10 paths likely carries too much one-path failure.
390 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
392 // The median hop CLTV expiry delta currently seen in the network.
393 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
395 // During routing, we only consider paths shorter than our maximum length estimate.
396 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
397 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
398 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
400 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
401 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
402 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
403 // (payment_secret and total_msat) = 93 bytes for the final hop.
404 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
405 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
406 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
408 /// The recipient of a payment.
409 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
410 pub struct PaymentParameters {
411 /// The node id of the payee.
412 pub payee_pubkey: PublicKey,
414 /// Features supported by the payee.
416 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
417 /// does not contain any features.
419 /// [`for_keysend`]: Self::for_keysend
420 pub features: Option<InvoiceFeatures>,
422 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
423 pub route_hints: Vec<RouteHint>,
425 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
426 pub expiry_time: Option<u64>,
428 /// The maximum total CLTV delta we accept for the route.
429 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
430 pub max_total_cltv_expiry_delta: u32,
432 /// The maximum number of paths that may be used by (MPP) payments.
433 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
434 pub max_path_count: u8,
436 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
437 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
438 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
439 /// increasing failure probability for those paths.
441 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
442 /// restriction have been found. While paths which meet this criteria will be searched for, it
443 /// is ultimately up to the scorer to select them over other paths.
445 /// A value of 0 will allow payments up to and including a channel's total announced usable
446 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
449 pub max_channel_saturation_power_of_half: u8,
451 /// A list of SCIDs which this payment was previously attempted over and which caused the
452 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
454 pub previously_failed_channels: Vec<u64>,
457 impl_writeable_tlv_based!(PaymentParameters, {
458 (0, payee_pubkey, required),
459 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
460 (2, features, option),
461 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
462 (4, route_hints, vec_type),
463 (5, max_channel_saturation_power_of_half, (default_value, 2)),
464 (6, expiry_time, option),
465 (7, previously_failed_channels, vec_type),
468 impl PaymentParameters {
469 /// Creates a payee with the node id of the given `pubkey`.
470 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
476 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
477 max_path_count: DEFAULT_MAX_PATH_COUNT,
478 max_channel_saturation_power_of_half: 2,
479 previously_failed_channels: Vec::new(),
483 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
484 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
485 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
488 /// Includes the payee's features.
490 /// (C-not exported) since bindings don't support move semantics
491 pub fn with_features(self, features: InvoiceFeatures) -> Self {
492 Self { features: Some(features), ..self }
495 /// Includes hints for routing to the payee.
497 /// (C-not exported) since bindings don't support move semantics
498 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
499 Self { route_hints, ..self }
502 /// Includes a payment expiration in seconds relative to the UNIX epoch.
504 /// (C-not exported) since bindings don't support move semantics
505 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
506 Self { expiry_time: Some(expiry_time), ..self }
509 /// Includes a limit for the total CLTV expiry delta which is considered during routing
511 /// (C-not exported) since bindings don't support move semantics
512 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
513 Self { max_total_cltv_expiry_delta, ..self }
516 /// Includes a limit for the maximum number of payment paths that may be used.
518 /// (C-not exported) since bindings don't support move semantics
519 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
520 Self { max_path_count, ..self }
523 /// Includes a limit for the maximum number of payment paths that may be used.
525 /// (C-not exported) since bindings don't support move semantics
526 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
527 Self { max_channel_saturation_power_of_half, ..self }
531 /// A list of hops along a payment path terminating with a channel to the recipient.
532 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
533 pub struct RouteHint(pub Vec<RouteHintHop>);
535 impl Writeable for RouteHint {
536 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
537 (self.0.len() as u64).write(writer)?;
538 for hop in self.0.iter() {
545 impl Readable for RouteHint {
546 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
547 let hop_count: u64 = Readable::read(reader)?;
548 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
549 for _ in 0..hop_count {
550 hops.push(Readable::read(reader)?);
556 /// A channel descriptor for a hop along a payment path.
557 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
558 pub struct RouteHintHop {
559 /// The node_id of the non-target end of the route
560 pub src_node_id: PublicKey,
561 /// The short_channel_id of this channel
562 pub short_channel_id: u64,
563 /// The fees which must be paid to use this channel
564 pub fees: RoutingFees,
565 /// The difference in CLTV values between this node and the next node.
566 pub cltv_expiry_delta: u16,
567 /// The minimum value, in msat, which must be relayed to the next hop.
568 pub htlc_minimum_msat: Option<u64>,
569 /// The maximum value in msat available for routing with a single HTLC.
570 pub htlc_maximum_msat: Option<u64>,
573 impl_writeable_tlv_based!(RouteHintHop, {
574 (0, src_node_id, required),
575 (1, htlc_minimum_msat, option),
576 (2, short_channel_id, required),
577 (3, htlc_maximum_msat, option),
579 (6, cltv_expiry_delta, required),
582 #[derive(Eq, PartialEq)]
583 struct RouteGraphNode {
585 lowest_fee_to_node: u64,
586 total_cltv_delta: u32,
587 // The maximum value a yet-to-be-constructed payment path might flow through this node.
588 // This value is upper-bounded by us by:
589 // - how much is needed for a path being constructed
590 // - how much value can channels following this node (up to the destination) can contribute,
591 // considering their capacity and fees
592 value_contribution_msat: u64,
593 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
594 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
595 path_htlc_minimum_msat: u64,
596 /// All penalties incurred from this hop on the way to the destination, as calculated using
598 path_penalty_msat: u64,
599 /// The number of hops walked up to this node.
600 path_length_to_node: u8,
603 impl cmp::Ord for RouteGraphNode {
604 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
605 let other_score = cmp::max(other.lowest_fee_to_node, other.path_htlc_minimum_msat)
606 .saturating_add(other.path_penalty_msat);
607 let self_score = cmp::max(self.lowest_fee_to_node, self.path_htlc_minimum_msat)
608 .saturating_add(self.path_penalty_msat);
609 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
613 impl cmp::PartialOrd for RouteGraphNode {
614 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
615 Some(self.cmp(other))
619 /// A wrapper around the various hop representations.
621 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
622 #[derive(Clone, Debug)]
623 enum CandidateRouteHop<'a> {
624 /// A hop from the payer, where the outbound liquidity is known.
626 details: &'a ChannelDetails,
628 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
630 info: DirectedChannelInfo<'a>,
631 short_channel_id: u64,
633 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
635 hint: &'a RouteHintHop,
639 impl<'a> CandidateRouteHop<'a> {
640 fn short_channel_id(&self) -> u64 {
642 CandidateRouteHop::FirstHop { details } => details.get_outbound_payment_scid().unwrap(),
643 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
644 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
648 // NOTE: This may alloc memory so avoid calling it in a hot code path.
649 fn features(&self) -> ChannelFeatures {
651 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
652 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
653 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
657 fn cltv_expiry_delta(&self) -> u32 {
659 CandidateRouteHop::FirstHop { .. } => 0,
660 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
661 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
665 fn htlc_minimum_msat(&self) -> u64 {
667 CandidateRouteHop::FirstHop { .. } => 0,
668 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
669 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
673 fn fees(&self) -> RoutingFees {
675 CandidateRouteHop::FirstHop { .. } => RoutingFees {
676 base_msat: 0, proportional_millionths: 0,
678 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
679 CandidateRouteHop::PrivateHop { hint } => hint.fees,
683 fn effective_capacity(&self) -> EffectiveCapacity {
685 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
686 liquidity_msat: details.next_outbound_htlc_limit_msat,
688 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
689 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
695 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
696 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
698 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
699 EffectiveCapacity::Infinite => u64::max_value(),
700 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
701 EffectiveCapacity::MaximumHTLC { amount_msat } =>
702 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
703 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
704 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
708 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
709 -> bool where I1::Item: PartialEq<I2::Item> {
711 let a = iter_a.next();
712 let b = iter_b.next();
713 if a.is_none() && b.is_none() { return true; }
714 if a.is_none() || b.is_none() { return false; }
715 if a.unwrap().ne(&b.unwrap()) { return false; }
719 /// It's useful to keep track of the hops associated with the fees required to use them,
720 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
721 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
722 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
724 struct PathBuildingHop<'a> {
725 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
726 // is a larger refactor and will require careful performance analysis.
728 candidate: CandidateRouteHop<'a>,
731 /// All the fees paid *after* this channel on the way to the destination
732 next_hops_fee_msat: u64,
733 /// Fee paid for the use of the current channel (see candidate.fees()).
734 /// The value will be actually deducted from the counterparty balance on the previous link.
735 hop_use_fee_msat: u64,
736 /// Used to compare channels when choosing the for routing.
737 /// Includes paying for the use of a hop and the following hops, as well as
738 /// an estimated cost of reaching this hop.
739 /// Might get stale when fees are recomputed. Primarily for internal use.
741 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
742 /// walk and may be invalid thereafter.
743 path_htlc_minimum_msat: u64,
744 /// All penalties incurred from this channel on the way to the destination, as calculated using
746 path_penalty_msat: u64,
747 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
748 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
749 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
750 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
751 /// avoid processing them again.
753 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
754 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
755 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
756 // value_contribution_msat, which requires tracking it here. See comments below where it is
757 // used for more info.
758 value_contribution_msat: u64,
761 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
762 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
763 let mut debug_struct = f.debug_struct("PathBuildingHop");
765 .field("node_id", &self.node_id)
766 .field("short_channel_id", &self.candidate.short_channel_id())
767 .field("total_fee_msat", &self.total_fee_msat)
768 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
769 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
770 .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)))
771 .field("path_penalty_msat", &self.path_penalty_msat)
772 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
773 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
774 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
775 let debug_struct = debug_struct
776 .field("value_contribution_msat", &self.value_contribution_msat);
777 debug_struct.finish()
781 // Instantiated with a list of hops with correct data in them collected during path finding,
782 // an instance of this struct should be further modified only via given methods.
784 struct PaymentPath<'a> {
785 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
788 impl<'a> PaymentPath<'a> {
789 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
790 fn get_value_msat(&self) -> u64 {
791 self.hops.last().unwrap().0.fee_msat
794 fn get_path_penalty_msat(&self) -> u64 {
795 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
798 fn get_total_fee_paid_msat(&self) -> u64 {
799 if self.hops.len() < 1 {
803 // Can't use next_hops_fee_msat because it gets outdated.
804 for (i, (hop, _)) in self.hops.iter().enumerate() {
805 if i != self.hops.len() - 1 {
806 result += hop.fee_msat;
812 fn get_cost_msat(&self) -> u64 {
813 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
816 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
817 // to change fees may result in an inconsistency.
819 // Sometimes we call this function right after constructing a path which is inconsistent in
820 // that it the value being transferred has decreased while we were doing path finding, leading
821 // to the fees being paid not lining up with the actual limits.
823 // Note that this function is not aware of the available_liquidity limit, and thus does not
824 // support increasing the value being transferred beyond what was selected during the initial
826 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
827 let mut total_fee_paid_msat = 0 as u64;
828 for i in (0..self.hops.len()).rev() {
829 let last_hop = i == self.hops.len() - 1;
831 // For non-last-hop, this value will represent the fees paid on the current hop. It
832 // will consist of the fees for the use of the next hop, and extra fees to match
833 // htlc_minimum_msat of the current channel. Last hop is handled separately.
834 let mut cur_hop_fees_msat = 0;
836 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
839 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
840 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
841 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
842 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
843 // set it too high just to maliciously take more fees by exploiting this
844 // match htlc_minimum_msat logic.
845 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
846 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
847 // Note that there is a risk that *previous hops* (those closer to us, as we go
848 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
850 // This might make us end up with a broken route, although this should be super-rare
851 // in practice, both because of how healthy channels look like, and how we pick
852 // channels in add_entry.
853 // Also, this can't be exploited more heavily than *announce a free path and fail
855 cur_hop_transferred_amount_msat += extra_fees_msat;
856 total_fee_paid_msat += extra_fees_msat;
857 cur_hop_fees_msat += extra_fees_msat;
861 // Final hop is a special case: it usually has just value_msat (by design), but also
862 // it still could overpay for the htlc_minimum_msat.
863 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
865 // Propagate updated fees for the use of the channels to one hop back, where they
866 // will be actually paid (fee_msat). The last hop is handled above separately.
867 cur_hop.fee_msat = cur_hop_fees_msat;
870 // Fee for the use of the current hop which will be deducted on the previous hop.
871 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
872 // this channel is free for us.
874 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
875 cur_hop.hop_use_fee_msat = new_fee;
876 total_fee_paid_msat += new_fee;
878 // It should not be possible because this function is called only to reduce the
879 // value. In that case, compute_fee was already called with the same fees for
880 // larger amount and there was no overflow.
888 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
889 let proportional_fee_millions =
890 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
891 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
892 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
896 // This function may be (indirectly) called without any verification,
897 // with channel_fees provided by a caller. We should handle it gracefully.
902 /// The default `features` we assume for a node in a route, when no `features` are known about that
905 /// Default features are:
906 /// * variable_length_onion_optional
907 fn default_node_features() -> NodeFeatures {
908 let mut features = NodeFeatures::empty();
909 features.set_variable_length_onion_optional();
913 /// Finds a route from us (payer) to the given target node (payee).
915 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
916 /// Without this, MPP will only be used if the payee's features are available in the network graph.
918 /// Private routing paths between a public node and the target may be included in `params.payee`.
920 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
921 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
922 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
924 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
925 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
926 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
930 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
931 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
936 /// Panics if first_hops contains channels without short_channel_ids;
937 /// [`ChannelManager::list_usable_channels`] will never include such channels.
939 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
940 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
941 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
942 pub fn find_route<L: Deref, GL: Deref, S: Score>(
943 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
944 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
945 scorer: &S, random_seed_bytes: &[u8; 32]
946 ) -> Result<Route, LightningError>
947 where L::Target: Logger, GL::Target: Logger {
948 let graph_lock = network_graph.read_only();
949 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
950 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, scorer,
952 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
956 pub(crate) fn get_route<L: Deref, S: Score>(
957 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
958 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
959 logger: L, scorer: &S, _random_seed_bytes: &[u8; 32]
960 ) -> Result<Route, LightningError>
961 where L::Target: Logger {
962 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
963 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
965 if payee_node_id == our_node_id {
966 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
969 if final_value_msat > MAX_VALUE_MSAT {
970 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
973 if final_value_msat == 0 {
974 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
977 for route in payment_params.route_hints.iter() {
978 for hop in &route.0 {
979 if hop.src_node_id == payment_params.payee_pubkey {
980 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
984 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
985 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});
988 // The general routing idea is the following:
989 // 1. Fill first/last hops communicated by the caller.
990 // 2. Attempt to construct a path from payer to payee for transferring
991 // any ~sufficient (described later) value.
992 // If succeed, remember which channels were used and how much liquidity they have available,
993 // so that future paths don't rely on the same liquidity.
994 // 3. Proceed to the next step if:
995 // - we hit the recommended target value;
996 // - OR if we could not construct a new path. Any next attempt will fail too.
997 // Otherwise, repeat step 2.
998 // 4. See if we managed to collect paths which aggregately are able to transfer target value
999 // (not recommended value).
1000 // 5. If yes, proceed. If not, fail routing.
1001 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1002 // transferred up to the transfer target value.
1003 // 7. Reduce the value of the last path until we are sending only the target value.
1004 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1005 // them so that we're not sending two HTLCs along the same path.
1007 // As for the actual search algorithm, we do a payee-to-payer Dijkstra's sorting by each node's
1008 // distance from the payee
1010 // We are not a faithful Dijkstra's implementation because we can change values which impact
1011 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1012 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1013 // the value we are currently attempting to send over a path, we simply reduce the value being
1014 // sent along the path for any hops after that channel. This may imply that later fees (which
1015 // we've already tabulated) are lower because a smaller value is passing through the channels
1016 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1017 // channels which were selected earlier (and which may still be used for other paths without a
1018 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1021 // One potentially problematic case for this algorithm would be if there are many
1022 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1023 // graph walking), we may never find a path which is not liquidity-limited and has lower
1024 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1025 // Because we only consider paths with at least 5% of the total value being sent, the damage
1026 // from such a case should be limited, however this could be further reduced in the future by
1027 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1028 // limits for the purposes of fee calculation.
1030 // Alternatively, we could store more detailed path information in the heap (targets, below)
1031 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1032 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1033 // and practically (as we would need to store dynamically-allocated path information in heap
1034 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1035 // results of such an algorithm would likely be biased towards lower-value paths.
1037 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1038 // outside of our current search value, running a path search more times to gather candidate
1039 // paths at different values. While this may be acceptable, further path searches may increase
1040 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1041 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1042 // the same time, remaining generic across different payment values.
1044 let network_channels = network_graph.channels();
1045 let network_nodes = network_graph.nodes();
1047 if payment_params.max_path_count == 0 {
1048 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1051 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1052 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1054 let allow_mpp = if payment_params.max_path_count == 1 {
1056 } else if let Some(features) = &payment_params.features {
1057 features.supports_basic_mpp()
1058 } else if let Some(node) = network_nodes.get(&payee_node_id) {
1059 if let Some(node_info) = node.announcement_info.as_ref() {
1060 node_info.features.supports_basic_mpp()
1064 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1065 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
1066 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1069 // Prepare the data we'll use for payee-to-payer search by
1070 // inserting first hops suggested by the caller as targets.
1071 // Our search will then attempt to reach them while traversing from the payee node.
1072 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1073 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1074 if let Some(hops) = first_hops {
1076 if chan.get_outbound_payment_scid().is_none() {
1077 panic!("first_hops should be filled in with usable channels, not pending ones");
1079 if chan.counterparty.node_id == *our_node_pubkey {
1080 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1083 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1084 .or_insert(Vec::new())
1087 if first_hop_targets.is_empty() {
1088 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1092 // The main heap containing all candidate next-hops sorted by their score (max(fee,
1093 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1094 // adding duplicate entries when we find a better path to a given node.
1095 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1097 // Map from node_id to information about the best current path to that node, including feerate
1099 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1101 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1102 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1103 // htlc_minimum with extra fees while still finding a cheaper path.
1104 let mut hit_minimum_limit;
1106 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1107 // We start with a path_value of the exact amount we want, and if that generates a route we may
1108 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1109 // amount we want in total across paths, selecting the best subset at the end.
1110 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1111 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1112 let mut path_value_msat = final_value_msat;
1114 // Routing Fragmentation Mitigation heuristic:
1116 // Routing fragmentation across many payment paths increases the overall routing
1117 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1118 // Taking too many smaller paths also increases the chance of payment failure.
1119 // Thus to avoid this effect, we require from our collected links to provide
1120 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1121 // This requirement is currently set to be 1/max_path_count of the payment
1122 // value to ensure we only ever return routes that do not violate this limit.
1123 let minimal_value_contribution_msat: u64 = if allow_mpp {
1124 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1129 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1130 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1131 // drop the requirement by setting this to 0.
1132 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1134 // Keep track of how much liquidity has been used in selected channels. Used to determine
1135 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
1136 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
1137 // liquidity used in one direction will not offset any used in the opposite direction.
1138 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
1139 HashMap::with_capacity(network_nodes.len());
1141 // Keeping track of how much value we already collected across other paths. Helps to decide
1142 // when we want to stop looking for new paths.
1143 let mut already_collected_value_msat = 0;
1145 for (_, channels) in first_hop_targets.iter_mut() {
1146 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1147 // most like to use.
1149 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1150 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1153 // Second, because simply always sorting in descending order would always use our largest
1154 // available outbound capacity, needlessly fragmenting our available channel capacities,
1155 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1156 // which have enough, but not too much, capacity for the payment.
1157 channels.sort_unstable_by(|chan_a, chan_b| {
1158 if chan_b.next_outbound_htlc_limit_msat < recommended_value_msat || chan_a.next_outbound_htlc_limit_msat < recommended_value_msat {
1159 // Sort in descending order
1160 chan_b.next_outbound_htlc_limit_msat.cmp(&chan_a.next_outbound_htlc_limit_msat)
1162 // Sort in ascending order
1163 chan_a.next_outbound_htlc_limit_msat.cmp(&chan_b.next_outbound_htlc_limit_msat)
1168 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
1170 macro_rules! add_entry {
1171 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1172 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1173 // since that value has to be transferred over this channel.
1174 // Returns whether this channel caused an update to `targets`.
1175 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1176 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1177 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1178 // We "return" whether we updated the path at the end, via this:
1179 let mut did_add_update_path_to_src_node = false;
1180 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1181 // practice these cases should be caught earlier:
1182 // - for regular channels at channel announcement (TODO)
1183 // - for first and last hops early in get_route
1184 if $src_node_id != $dest_node_id {
1185 let short_channel_id = $candidate.short_channel_id();
1186 let effective_capacity = $candidate.effective_capacity();
1187 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1189 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1190 // It may be misleading because we might later choose to reduce the value transferred
1191 // over these channels, and the channel which was insufficient might become sufficient.
1192 // Worst case: we drop a good channel here because it can't cover the high following
1193 // fees caused by one expensive channel, but then this channel could have been used
1194 // if the amount being transferred over this path is lower.
1195 // We do this for now, but this is a subject for removal.
1196 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1197 let used_liquidity_msat = used_channel_liquidities
1198 .get(&(short_channel_id, $src_node_id < $dest_node_id))
1199 .map_or(0, |used_liquidity_msat| {
1200 available_value_contribution_msat = available_value_contribution_msat
1201 .saturating_sub(*used_liquidity_msat);
1202 *used_liquidity_msat
1205 // Verify the liquidity offered by this channel complies to the minimal contribution.
1206 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1207 // Do not consider candidate hops that would exceed the maximum path length.
1208 let path_length_to_node = $next_hops_path_length + 1;
1209 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1211 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1212 // In order to already account for some of the privacy enhancing random CLTV
1213 // expiry delta offset we add on top later, we subtract a rough estimate
1214 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1215 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1216 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1217 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1218 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1219 .saturating_add($candidate.cltv_expiry_delta());
1220 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1222 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1223 // Includes paying fees for the use of the following channels.
1224 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1225 Some(result) => result,
1226 // Can't overflow due to how the values were computed right above.
1227 None => unreachable!(),
1229 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1230 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1231 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1233 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1234 let may_overpay_to_meet_path_minimum_msat =
1235 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1236 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1237 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1238 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1240 let payment_failed_on_this_channel =
1241 payment_params.previously_failed_channels.contains(&short_channel_id);
1243 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1244 // bother considering this channel. If retrying with recommended_value_msat may
1245 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1246 // around again with a higher amount.
1247 if !contributes_sufficient_value || exceeds_max_path_length ||
1248 exceeds_cltv_delta_limit || payment_failed_on_this_channel {
1249 // Path isn't useful, ignore it and move on.
1250 } else if may_overpay_to_meet_path_minimum_msat {
1251 hit_minimum_limit = true;
1252 } else if over_path_minimum_msat {
1253 // Note that low contribution here (limited by available_liquidity_msat)
1254 // might violate htlc_minimum_msat on the hops which are next along the
1255 // payment path (upstream to the payee). To avoid that, we recompute
1256 // path fees knowing the final path contribution after constructing it.
1257 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
1258 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
1259 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
1260 .unwrap_or_else(|| u64::max_value());
1261 let hm_entry = dist.entry($src_node_id);
1262 let old_entry = hm_entry.or_insert_with(|| {
1263 // If there was previously no known way to access the source node
1264 // (recall it goes payee-to-payer) of short_channel_id, first add a
1265 // semi-dummy record just to compute the fees to reach the source node.
1266 // This will affect our decision on selecting short_channel_id
1267 // as a way to reach the $dest_node_id.
1269 node_id: $dest_node_id.clone(),
1270 candidate: $candidate.clone(),
1272 next_hops_fee_msat: u64::max_value(),
1273 hop_use_fee_msat: u64::max_value(),
1274 total_fee_msat: u64::max_value(),
1275 path_htlc_minimum_msat,
1276 path_penalty_msat: u64::max_value(),
1277 was_processed: false,
1278 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1279 value_contribution_msat,
1283 #[allow(unused_mut)] // We only use the mut in cfg(test)
1284 let mut should_process = !old_entry.was_processed;
1285 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1287 // In test/fuzzing builds, we do extra checks to make sure the skipping
1288 // of already-seen nodes only happens in cases we expect (see below).
1289 if !should_process { should_process = true; }
1293 let mut hop_use_fee_msat = 0;
1294 let mut total_fee_msat = $next_hops_fee_msat;
1296 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1297 // will have the same effective-fee
1298 if $src_node_id != our_node_id {
1299 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1300 // max_value means we'll always fail
1301 // the old_entry.total_fee_msat > total_fee_msat check
1302 None => total_fee_msat = u64::max_value(),
1304 hop_use_fee_msat = fee_msat;
1305 total_fee_msat += hop_use_fee_msat;
1310 let channel_usage = ChannelUsage {
1311 amount_msat: amount_to_transfer_over_msat,
1312 inflight_htlc_msat: used_liquidity_msat,
1315 let channel_penalty_msat = scorer.channel_penalty_msat(
1316 short_channel_id, &$src_node_id, &$dest_node_id, channel_usage
1318 let path_penalty_msat = $next_hops_path_penalty_msat
1319 .saturating_add(channel_penalty_msat);
1320 let new_graph_node = RouteGraphNode {
1321 node_id: $src_node_id,
1322 lowest_fee_to_node: total_fee_msat,
1323 total_cltv_delta: hop_total_cltv_delta,
1324 value_contribution_msat,
1325 path_htlc_minimum_msat,
1327 path_length_to_node,
1330 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1331 // if this way is cheaper than the already known
1332 // (considering the cost to "reach" this channel from the route destination,
1333 // the cost of using this channel,
1334 // and the cost of routing to the source node of this channel).
1335 // Also, consider that htlc_minimum_msat_difference, because we might end up
1336 // paying it. Consider the following exploit:
1337 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1338 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1339 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1340 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1342 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1343 // but it may require additional tracking - we don't want to double-count
1344 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1345 // can't use something that may decrease on future hops.
1346 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1347 .saturating_add(old_entry.path_penalty_msat);
1348 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1349 .saturating_add(path_penalty_msat);
1351 if !old_entry.was_processed && new_cost < old_cost {
1352 targets.push(new_graph_node);
1353 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1354 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1355 old_entry.total_fee_msat = total_fee_msat;
1356 old_entry.node_id = $dest_node_id.clone();
1357 old_entry.candidate = $candidate.clone();
1358 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1359 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1360 old_entry.path_penalty_msat = path_penalty_msat;
1361 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1363 old_entry.value_contribution_msat = value_contribution_msat;
1365 did_add_update_path_to_src_node = true;
1366 } else if old_entry.was_processed && new_cost < old_cost {
1367 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1369 // If we're skipping processing a node which was previously
1370 // processed even though we found another path to it with a
1371 // cheaper fee, check that it was because the second path we
1372 // found (which we are processing now) has a lower value
1373 // contribution due to an HTLC minimum limit.
1375 // e.g. take a graph with two paths from node 1 to node 2, one
1376 // through channel A, and one through channel B. Channel A and
1377 // B are both in the to-process heap, with their scores set by
1378 // a higher htlc_minimum than fee.
1379 // Channel A is processed first, and the channels onwards from
1380 // node 1 are added to the to-process heap. Thereafter, we pop
1381 // Channel B off of the heap, note that it has a much more
1382 // restrictive htlc_maximum_msat, and recalculate the fees for
1383 // all of node 1's channels using the new, reduced, amount.
1385 // This would be bogus - we'd be selecting a higher-fee path
1386 // with a lower htlc_maximum_msat instead of the one we'd
1387 // already decided to use.
1388 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1390 value_contribution_msat + path_penalty_msat <
1391 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1399 did_add_update_path_to_src_node
1403 let default_node_features = default_node_features();
1405 // Find ways (channels with destination) to reach a given node and store them
1406 // in the corresponding data structures (routing graph etc).
1407 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1408 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1409 // This data can later be helpful to optimize routing (pay lower fees).
1410 macro_rules! add_entries_to_cheapest_to_target_node {
1411 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1412 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1413 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1414 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1415 let was_processed = elem.was_processed;
1416 elem.was_processed = true;
1419 // Entries are added to dist in add_entry!() when there is a channel from a node.
1420 // Because there are no channels from payee, it will not have a dist entry at this point.
1421 // If we're processing any other node, it is always be the result of a channel from it.
1422 assert_eq!($node_id, payee_node_id);
1427 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1428 for details in first_channels {
1429 let candidate = CandidateRouteHop::FirstHop { details };
1430 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1431 $next_hops_value_contribution,
1432 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1433 $next_hops_cltv_delta, $next_hops_path_length);
1437 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1440 &default_node_features
1443 if !features.requires_unknown_bits() {
1444 for chan_id in $node.channels.iter() {
1445 let chan = network_channels.get(chan_id).unwrap();
1446 if !chan.features.requires_unknown_bits() {
1447 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1448 if first_hops.is_none() || *source != our_node_id {
1449 if directed_channel.direction().enabled {
1450 let candidate = CandidateRouteHop::PublicHop {
1451 info: directed_channel,
1452 short_channel_id: *chan_id,
1454 add_entry!(candidate, *source, $node_id,
1455 $fee_to_target_msat,
1456 $next_hops_value_contribution,
1457 $next_hops_path_htlc_minimum_msat,
1458 $next_hops_path_penalty_msat,
1459 $next_hops_cltv_delta, $next_hops_path_length);
1470 let mut payment_paths = Vec::<PaymentPath>::new();
1472 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1473 'paths_collection: loop {
1474 // For every new path, start from scratch, except for used_channel_liquidities, which
1475 // helps to avoid reusing previously selected paths in future iterations.
1478 hit_minimum_limit = false;
1480 // If first hop is a private channel and the only way to reach the payee, this is the only
1481 // place where it could be added.
1482 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1483 for details in first_channels {
1484 let candidate = CandidateRouteHop::FirstHop { details };
1485 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat,
1487 log_trace!(logger, "{} direct route to payee via SCID {}",
1488 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1492 // Add the payee as a target, so that the payee-to-payer
1493 // search algorithm knows what to start with.
1494 match network_nodes.get(&payee_node_id) {
1495 // The payee is not in our network graph, so nothing to add here.
1496 // There is still a chance of reaching them via last_hops though,
1497 // so don't yet fail the payment here.
1498 // If not, targets.pop() will not even let us enter the loop in step 2.
1501 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0, 0);
1506 // If a caller provided us with last hops, add them to routing targets. Since this happens
1507 // earlier than general path finding, they will be somewhat prioritized, although currently
1508 // it matters only if the fees are exactly the same.
1509 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1510 let first_hop_in_route = &(route.0)[0];
1511 let have_hop_src_in_graph =
1512 // Only add the hops in this route to our candidate set if either
1513 // we have a direct channel to the first hop or the first hop is
1514 // in the regular network graph.
1515 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1516 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1517 if have_hop_src_in_graph {
1518 // We start building the path from reverse, i.e., from payee
1519 // to the first RouteHintHop in the path.
1520 let hop_iter = route.0.iter().rev();
1521 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1522 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1523 let mut hop_used = true;
1524 let mut aggregate_next_hops_fee_msat: u64 = 0;
1525 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1526 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1527 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1528 let mut aggregate_next_hops_path_length: u8 = 0;
1530 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1531 let source = NodeId::from_pubkey(&hop.src_node_id);
1532 let target = NodeId::from_pubkey(&prev_hop_id);
1533 let candidate = network_channels
1534 .get(&hop.short_channel_id)
1535 .and_then(|channel| channel.as_directed_to(&target))
1536 .map(|(info, _)| CandidateRouteHop::PublicHop {
1538 short_channel_id: hop.short_channel_id,
1540 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1542 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat,
1543 path_value_msat, aggregate_next_hops_path_htlc_minimum_msat,
1544 aggregate_next_hops_path_penalty_msat,
1545 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length) {
1546 // If this hop was not used then there is no use checking the preceding
1547 // hops in the RouteHint. We can break by just searching for a direct
1548 // channel between last checked hop and first_hop_targets.
1552 let used_liquidity_msat = used_channel_liquidities
1553 .get(&(hop.short_channel_id, source < target)).copied().unwrap_or(0);
1554 let channel_usage = ChannelUsage {
1555 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
1556 inflight_htlc_msat: used_liquidity_msat,
1557 effective_capacity: candidate.effective_capacity(),
1559 let channel_penalty_msat = scorer.channel_penalty_msat(
1560 hop.short_channel_id, &source, &target, channel_usage
1562 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1563 .saturating_add(channel_penalty_msat);
1565 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1566 .saturating_add(hop.cltv_expiry_delta as u32);
1568 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1571 // Searching for a direct channel between last checked hop and first_hop_targets
1572 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1573 for details in first_channels {
1574 let candidate = CandidateRouteHop::FirstHop { details };
1575 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1576 aggregate_next_hops_fee_msat, path_value_msat,
1577 aggregate_next_hops_path_htlc_minimum_msat,
1578 aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta,
1579 aggregate_next_hops_path_length);
1587 // In the next values of the iterator, the aggregate fees already reflects
1588 // the sum of value sent from payer (final_value_msat) and routing fees
1589 // for the last node in the RouteHint. We need to just add the fees to
1590 // route through the current node so that the preceding node (next iteration)
1592 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1593 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1594 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1596 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1597 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1598 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1599 .checked_add(hop_htlc_minimum_msat_inc);
1600 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1602 if idx == route.0.len() - 1 {
1603 // The last hop in this iterator is the first hop in
1604 // overall RouteHint.
1605 // If this hop connects to a node with which we have a direct channel,
1606 // ignore the network graph and, if the last hop was added, add our
1607 // direct channel to the candidate set.
1609 // Note that we *must* check if the last hop was added as `add_entry`
1610 // always assumes that the third argument is a node to which we have a
1612 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1613 for details in first_channels {
1614 let candidate = CandidateRouteHop::FirstHop { details };
1615 add_entry!(candidate, our_node_id,
1616 NodeId::from_pubkey(&hop.src_node_id),
1617 aggregate_next_hops_fee_msat, path_value_msat,
1618 aggregate_next_hops_path_htlc_minimum_msat,
1619 aggregate_next_hops_path_penalty_msat,
1620 aggregate_next_hops_cltv_delta,
1621 aggregate_next_hops_path_length);
1629 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1631 // At this point, targets are filled with the data from first and
1632 // last hops communicated by the caller, and the payment receiver.
1633 let mut found_new_path = false;
1636 // If this loop terminates due the exhaustion of targets, two situations are possible:
1637 // - not enough outgoing liquidity:
1638 // 0 < already_collected_value_msat < final_value_msat
1639 // - enough outgoing liquidity:
1640 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1641 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1642 // paths_collection will be stopped because found_new_path==false.
1643 // This is not necessarily a routing failure.
1644 '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() {
1646 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1647 // traversing the graph and arrange the path out of what we found.
1648 if node_id == our_node_id {
1649 let mut new_entry = dist.remove(&our_node_id).unwrap();
1650 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1653 let mut features_set = false;
1654 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1655 for details in first_channels {
1656 if details.get_outbound_payment_scid().unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1657 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1658 features_set = true;
1664 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1665 if let Some(node_info) = node.announcement_info.as_ref() {
1666 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1668 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1671 // We can fill in features for everything except hops which were
1672 // provided via the invoice we're paying. We could guess based on the
1673 // recipient's features but for now we simply avoid guessing at all.
1677 // Means we succesfully traversed from the payer to the payee, now
1678 // save this path for the payment route. Also, update the liquidity
1679 // remaining on the used hops, so that we take them into account
1680 // while looking for more paths.
1681 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1685 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1686 Some(payment_hop) => payment_hop,
1687 // We can't arrive at None because, if we ever add an entry to targets,
1688 // we also fill in the entry in dist (see add_entry!).
1689 None => unreachable!(),
1691 // We "propagate" the fees one hop backward (topologically) here,
1692 // so that fees paid for a HTLC forwarding on the current channel are
1693 // associated with the previous channel (where they will be subtracted).
1694 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1695 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1697 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1698 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1700 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1701 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1703 let mut payment_path = PaymentPath {hops: ordered_hops};
1705 // We could have possibly constructed a slightly inconsistent path: since we reduce
1706 // value being transferred along the way, we could have violated htlc_minimum_msat
1707 // on some channels we already passed (assuming dest->source direction). Here, we
1708 // recompute the fees again, so that if that's the case, we match the currently
1709 // underpaid htlc_minimum_msat with fees.
1710 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
1711 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
1712 payment_path.update_value_and_recompute_fees(value_contribution_msat);
1714 // Since a path allows to transfer as much value as
1715 // the smallest channel it has ("bottleneck"), we should recompute
1716 // the fees so sender HTLC don't overpay fees when traversing
1717 // larger channels than the bottleneck. This may happen because
1718 // when we were selecting those channels we were not aware how much value
1719 // this path will transfer, and the relative fee for them
1720 // might have been computed considering a larger value.
1721 // Remember that we used these channels so that we don't rely
1722 // on the same liquidity in future paths.
1723 let mut prevented_redundant_path_selection = false;
1724 let prev_hop_iter = core::iter::once(&our_node_id)
1725 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
1726 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
1727 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
1728 let used_liquidity_msat = used_channel_liquidities
1729 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
1730 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
1731 .or_insert(spent_on_hop_msat);
1732 let hop_capacity = hop.candidate.effective_capacity();
1733 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
1734 if *used_liquidity_msat == hop_max_msat {
1735 // If this path used all of this channel's available liquidity, we know
1736 // this path will not be selected again in the next loop iteration.
1737 prevented_redundant_path_selection = true;
1739 debug_assert!(*used_liquidity_msat <= hop_max_msat);
1741 if !prevented_redundant_path_selection {
1742 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1743 // we'll probably end up picking the same path again on the next iteration.
1744 // Decrease the available liquidity of a hop in the middle of the path.
1745 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1746 let exhausted = u64::max_value();
1747 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1748 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
1749 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
1752 // Track the total amount all our collected paths allow to send so that we know
1753 // when to stop looking for more paths
1754 already_collected_value_msat += value_contribution_msat;
1756 payment_paths.push(payment_path);
1757 found_new_path = true;
1758 break 'path_construction;
1761 // If we found a path back to the payee, we shouldn't try to process it again. This is
1762 // the equivalent of the `elem.was_processed` check in
1763 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1764 if node_id == payee_node_id { continue 'path_construction; }
1766 // Otherwise, since the current target node is not us,
1767 // keep "unrolling" the payment graph from payee to payer by
1768 // finding a way to reach the current target from the payer side.
1769 match network_nodes.get(&node_id) {
1772 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
1773 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
1774 total_cltv_delta, path_length_to_node);
1780 if !found_new_path && channel_saturation_pow_half != 0 {
1781 channel_saturation_pow_half = 0;
1782 continue 'paths_collection;
1784 // If we don't support MPP, no use trying to gather more value ever.
1785 break 'paths_collection;
1789 // Stop either when the recommended value is reached or if no new path was found in this
1791 // In the latter case, making another path finding attempt won't help,
1792 // because we deterministically terminated the search due to low liquidity.
1793 if !found_new_path && channel_saturation_pow_half != 0 {
1794 channel_saturation_pow_half = 0;
1795 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1796 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1797 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1798 break 'paths_collection;
1799 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1800 // Further, if this was our first walk of the graph, and we weren't limited by an
1801 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1802 // limited by an htlc_minimum_msat value, find another path with a higher value,
1803 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1804 // still keeping a lower total fee than this path.
1805 if !hit_minimum_limit {
1806 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1807 break 'paths_collection;
1809 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1810 path_value_msat = recommended_value_msat;
1815 if payment_paths.len() == 0 {
1816 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1819 if already_collected_value_msat < final_value_msat {
1820 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1824 let mut selected_route = payment_paths;
1826 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
1827 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
1829 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
1830 // the value they contribute towards the payment amount.
1831 // We sort in descending order as we will remove from the front in `retain`, next.
1832 selected_route.sort_unstable_by(|a, b|
1833 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
1834 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
1837 // We should make sure that at least 1 path left.
1838 let mut paths_left = selected_route.len();
1839 selected_route.retain(|path| {
1840 if paths_left == 1 {
1843 let path_value_msat = path.get_value_msat();
1844 if path_value_msat <= overpaid_value_msat {
1845 overpaid_value_msat -= path_value_msat;
1851 debug_assert!(selected_route.len() > 0);
1853 if overpaid_value_msat != 0 {
1855 // Now, subtract the remaining overpaid value from the most-expensive path.
1856 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1857 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1858 selected_route.sort_unstable_by(|a, b| {
1859 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1860 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1861 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1863 let expensive_payment_path = selected_route.first_mut().unwrap();
1865 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
1866 // can't go negative.
1867 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1868 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1872 // Sort by the path itself and combine redundant paths.
1873 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
1874 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
1876 selected_route.sort_unstable_by_key(|path| {
1877 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
1878 debug_assert!(path.hops.len() <= key.len());
1879 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
1884 for idx in 0..(selected_route.len() - 1) {
1885 if idx + 1 >= selected_route.len() { break; }
1886 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
1887 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
1888 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
1889 selected_route[idx].update_value_and_recompute_fees(new_value);
1890 selected_route.remove(idx + 1);
1894 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1895 for payment_path in selected_route {
1896 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1898 pubkey: PublicKey::from_slice(payment_hop.node_id.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &payment_hop.node_id), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
1899 node_features: node_features.clone(),
1900 short_channel_id: payment_hop.candidate.short_channel_id(),
1901 channel_features: payment_hop.candidate.features(),
1902 fee_msat: payment_hop.fee_msat,
1903 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1905 }).collect::<Vec<_>>();
1906 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1907 // applicable for the previous hop.
1908 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1909 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1911 selected_paths.push(path);
1913 // Make sure we would never create a route with more paths than we allow.
1914 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
1916 if let Some(features) = &payment_params.features {
1917 for path in selected_paths.iter_mut() {
1918 if let Ok(route_hop) = path.last_mut().unwrap() {
1919 route_hop.node_features = features.to_context();
1925 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1926 payment_params: Some(payment_params.clone()),
1928 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1932 // When an adversarial intermediary node observes a payment, it may be able to infer its
1933 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1934 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1935 // payment path by adding a randomized 'shadow route' offset to the final hop.
1936 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
1937 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
1939 let network_channels = network_graph.channels();
1940 let network_nodes = network_graph.nodes();
1942 for path in route.paths.iter_mut() {
1943 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1945 // Remember the last three nodes of the random walk and avoid looping back on them.
1946 // Init with the last three nodes from the actual path, if possible.
1947 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1948 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1949 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1951 // Choose the last publicly known node as the starting point for the random walk.
1952 let mut cur_hop: Option<NodeId> = None;
1953 let mut path_nonce = [0u8; 12];
1954 if let Some(starting_hop) = path.iter().rev()
1955 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1956 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1957 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1960 // Init PRNG with the path-dependant nonce, which is static for private paths.
1961 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1962 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1964 // Pick a random path length in [1 .. 3]
1965 prng.process_in_place(&mut random_path_bytes);
1966 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1968 for random_hop in 0..random_walk_length {
1969 // If we don't find a suitable offset in the public network graph, we default to
1970 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1971 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1973 if let Some(cur_node_id) = cur_hop {
1974 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1975 // Randomly choose the next unvisited hop.
1976 prng.process_in_place(&mut random_path_bytes);
1977 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1978 .checked_rem(cur_node.channels.len())
1979 .and_then(|index| cur_node.channels.get(index))
1980 .and_then(|id| network_channels.get(id)) {
1981 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1982 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1983 nodes_to_avoid[random_hop] = *next_id;
1984 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
1985 cur_hop = Some(*next_id);
1992 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1993 .checked_add(random_hop_offset)
1994 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1997 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1998 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1999 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2001 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2002 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2003 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
2004 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2005 max_path_offset = cmp::max(
2006 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2007 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2008 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2010 // Add 'shadow' CLTV offset to the final hop
2011 if let Some(last_hop) = path.last_mut() {
2012 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2013 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2018 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2019 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2021 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2022 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2023 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2024 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2025 ) -> Result<Route, LightningError>
2026 where L::Target: Logger, GL::Target: Logger {
2027 let graph_lock = network_graph.read_only();
2028 let mut route = build_route_from_hops_internal(
2029 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
2030 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
2031 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2035 fn build_route_from_hops_internal<L: Deref>(
2036 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
2037 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
2038 logger: L, random_seed_bytes: &[u8; 32]
2039 ) -> Result<Route, LightningError> where L::Target: Logger {
2042 our_node_id: NodeId,
2043 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2046 impl Score for HopScorer {
2047 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2048 _usage: ChannelUsage) -> u64
2050 let mut cur_id = self.our_node_id;
2051 for i in 0..self.hop_ids.len() {
2052 if let Some(next_id) = self.hop_ids[i] {
2053 if cur_id == *source && next_id == *target {
2064 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
2066 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
2068 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
2070 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
2073 impl<'a> Writeable for HopScorer {
2075 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2080 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2081 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2084 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2085 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2086 for i in 0..hops.len() {
2087 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2090 let scorer = HopScorer { our_node_id, hop_ids };
2092 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
2093 final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)
2098 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2099 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2100 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2101 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
2102 use crate::routing::scoring::{ChannelUsage, Score, ProbabilisticScorer, ProbabilisticScoringParameters};
2103 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2104 use crate::chain::transaction::OutPoint;
2105 use crate::chain::keysinterface::EntropySource;
2106 use crate::ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
2107 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2108 use crate::ln::channelmanager;
2109 use crate::util::config::UserConfig;
2110 use crate::util::test_utils as ln_test_utils;
2111 use crate::util::chacha20::ChaCha20;
2113 use crate::util::ser::{Writeable, Writer};
2115 use bitcoin::hashes::Hash;
2116 use bitcoin::network::constants::Network;
2117 use bitcoin::blockdata::constants::genesis_block;
2118 use bitcoin::blockdata::script::Builder;
2119 use bitcoin::blockdata::opcodes;
2120 use bitcoin::blockdata::transaction::TxOut;
2124 use bitcoin::secp256k1::{PublicKey,SecretKey};
2125 use bitcoin::secp256k1::Secp256k1;
2127 use crate::prelude::*;
2128 use crate::sync::Arc;
2130 use core::convert::TryInto;
2132 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2133 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2134 channelmanager::ChannelDetails {
2135 channel_id: [0; 32],
2136 counterparty: channelmanager::ChannelCounterparty {
2139 unspendable_punishment_reserve: 0,
2140 forwarding_info: None,
2141 outbound_htlc_minimum_msat: None,
2142 outbound_htlc_maximum_msat: None,
2144 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2147 outbound_scid_alias: None,
2148 inbound_scid_alias: None,
2149 channel_value_satoshis: 0,
2152 outbound_capacity_msat,
2153 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2154 inbound_capacity_msat: 42,
2155 unspendable_punishment_reserve: None,
2156 confirmations_required: None,
2157 confirmations: None,
2158 force_close_spend_delay: None,
2159 is_outbound: true, is_channel_ready: true,
2160 is_usable: true, is_public: true,
2161 inbound_htlc_minimum_msat: None,
2162 inbound_htlc_maximum_msat: None,
2168 fn simple_route_test() {
2169 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2170 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2171 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2172 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2173 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2174 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2176 // Simple route to 2 via 1
2178 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 0, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2179 assert_eq!(err, "Cannot send a payment of 0 msat");
2180 } else { panic!(); }
2182 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2183 assert_eq!(route.paths[0].len(), 2);
2185 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2186 assert_eq!(route.paths[0][0].short_channel_id, 2);
2187 assert_eq!(route.paths[0][0].fee_msat, 100);
2188 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2189 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2190 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2192 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2193 assert_eq!(route.paths[0][1].short_channel_id, 4);
2194 assert_eq!(route.paths[0][1].fee_msat, 100);
2195 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2196 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2197 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2201 fn invalid_first_hop_test() {
2202 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2203 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2204 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2205 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2206 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2207 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2209 // Simple route to 2 via 1
2211 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2213 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2214 get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2215 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2216 } else { panic!(); }
2218 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2219 assert_eq!(route.paths[0].len(), 2);
2223 fn htlc_minimum_test() {
2224 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2225 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2226 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2227 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2228 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2229 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2231 // Simple route to 2 via 1
2233 // Disable other paths
2234 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2235 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2236 short_channel_id: 12,
2238 flags: 2, // to disable
2239 cltv_expiry_delta: 0,
2240 htlc_minimum_msat: 0,
2241 htlc_maximum_msat: MAX_VALUE_MSAT,
2243 fee_proportional_millionths: 0,
2244 excess_data: Vec::new()
2246 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2247 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2248 short_channel_id: 3,
2250 flags: 2, // to disable
2251 cltv_expiry_delta: 0,
2252 htlc_minimum_msat: 0,
2253 htlc_maximum_msat: MAX_VALUE_MSAT,
2255 fee_proportional_millionths: 0,
2256 excess_data: Vec::new()
2258 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2259 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2260 short_channel_id: 13,
2262 flags: 2, // to disable
2263 cltv_expiry_delta: 0,
2264 htlc_minimum_msat: 0,
2265 htlc_maximum_msat: MAX_VALUE_MSAT,
2267 fee_proportional_millionths: 0,
2268 excess_data: Vec::new()
2270 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2271 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2272 short_channel_id: 6,
2274 flags: 2, // to disable
2275 cltv_expiry_delta: 0,
2276 htlc_minimum_msat: 0,
2277 htlc_maximum_msat: MAX_VALUE_MSAT,
2279 fee_proportional_millionths: 0,
2280 excess_data: Vec::new()
2282 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2283 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2284 short_channel_id: 7,
2286 flags: 2, // to disable
2287 cltv_expiry_delta: 0,
2288 htlc_minimum_msat: 0,
2289 htlc_maximum_msat: MAX_VALUE_MSAT,
2291 fee_proportional_millionths: 0,
2292 excess_data: Vec::new()
2295 // Check against amount_to_transfer_over_msat.
2296 // Set minimal HTLC of 200_000_000 msat.
2297 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2298 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2299 short_channel_id: 2,
2302 cltv_expiry_delta: 0,
2303 htlc_minimum_msat: 200_000_000,
2304 htlc_maximum_msat: MAX_VALUE_MSAT,
2306 fee_proportional_millionths: 0,
2307 excess_data: Vec::new()
2310 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2312 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2313 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2314 short_channel_id: 4,
2317 cltv_expiry_delta: 0,
2318 htlc_minimum_msat: 0,
2319 htlc_maximum_msat: 199_999_999,
2321 fee_proportional_millionths: 0,
2322 excess_data: Vec::new()
2325 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2326 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2327 assert_eq!(err, "Failed to find a path to the given destination");
2328 } else { panic!(); }
2330 // Lift the restriction on the first hop.
2331 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2332 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2333 short_channel_id: 2,
2336 cltv_expiry_delta: 0,
2337 htlc_minimum_msat: 0,
2338 htlc_maximum_msat: MAX_VALUE_MSAT,
2340 fee_proportional_millionths: 0,
2341 excess_data: Vec::new()
2344 // A payment above the minimum should pass
2345 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2346 assert_eq!(route.paths[0].len(), 2);
2350 fn htlc_minimum_overpay_test() {
2351 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2352 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2353 let config = UserConfig::default();
2354 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features(&config));
2355 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2356 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2357 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2359 // A route to node#2 via two paths.
2360 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2361 // Thus, they can't send 60 without overpaying.
2362 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2363 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2364 short_channel_id: 2,
2367 cltv_expiry_delta: 0,
2368 htlc_minimum_msat: 35_000,
2369 htlc_maximum_msat: 40_000,
2371 fee_proportional_millionths: 0,
2372 excess_data: Vec::new()
2374 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2375 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2376 short_channel_id: 12,
2379 cltv_expiry_delta: 0,
2380 htlc_minimum_msat: 35_000,
2381 htlc_maximum_msat: 40_000,
2383 fee_proportional_millionths: 0,
2384 excess_data: Vec::new()
2388 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2389 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2390 short_channel_id: 13,
2393 cltv_expiry_delta: 0,
2394 htlc_minimum_msat: 0,
2395 htlc_maximum_msat: MAX_VALUE_MSAT,
2397 fee_proportional_millionths: 0,
2398 excess_data: Vec::new()
2400 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2401 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2402 short_channel_id: 4,
2405 cltv_expiry_delta: 0,
2406 htlc_minimum_msat: 0,
2407 htlc_maximum_msat: MAX_VALUE_MSAT,
2409 fee_proportional_millionths: 0,
2410 excess_data: Vec::new()
2413 // Disable other paths
2414 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2415 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2416 short_channel_id: 1,
2418 flags: 2, // to disable
2419 cltv_expiry_delta: 0,
2420 htlc_minimum_msat: 0,
2421 htlc_maximum_msat: MAX_VALUE_MSAT,
2423 fee_proportional_millionths: 0,
2424 excess_data: Vec::new()
2427 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2428 // Overpay fees to hit htlc_minimum_msat.
2429 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2430 // TODO: this could be better balanced to overpay 10k and not 15k.
2431 assert_eq!(overpaid_fees, 15_000);
2433 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2434 // while taking even more fee to match htlc_minimum_msat.
2435 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2436 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2437 short_channel_id: 12,
2440 cltv_expiry_delta: 0,
2441 htlc_minimum_msat: 65_000,
2442 htlc_maximum_msat: 80_000,
2444 fee_proportional_millionths: 0,
2445 excess_data: Vec::new()
2447 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2448 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2449 short_channel_id: 2,
2452 cltv_expiry_delta: 0,
2453 htlc_minimum_msat: 0,
2454 htlc_maximum_msat: MAX_VALUE_MSAT,
2456 fee_proportional_millionths: 0,
2457 excess_data: Vec::new()
2459 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2460 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2461 short_channel_id: 4,
2464 cltv_expiry_delta: 0,
2465 htlc_minimum_msat: 0,
2466 htlc_maximum_msat: MAX_VALUE_MSAT,
2468 fee_proportional_millionths: 100_000,
2469 excess_data: Vec::new()
2472 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2473 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2474 assert_eq!(route.paths.len(), 1);
2475 assert_eq!(route.paths[0][0].short_channel_id, 12);
2476 let fees = route.paths[0][0].fee_msat;
2477 assert_eq!(fees, 5_000);
2479 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2480 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2481 // the other channel.
2482 assert_eq!(route.paths.len(), 1);
2483 assert_eq!(route.paths[0][0].short_channel_id, 2);
2484 let fees = route.paths[0][0].fee_msat;
2485 assert_eq!(fees, 5_000);
2489 fn disable_channels_test() {
2490 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2491 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2492 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2493 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2494 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2495 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2497 // // Disable channels 4 and 12 by flags=2
2498 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2499 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2500 short_channel_id: 4,
2502 flags: 2, // to disable
2503 cltv_expiry_delta: 0,
2504 htlc_minimum_msat: 0,
2505 htlc_maximum_msat: MAX_VALUE_MSAT,
2507 fee_proportional_millionths: 0,
2508 excess_data: Vec::new()
2510 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2511 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2512 short_channel_id: 12,
2514 flags: 2, // to disable
2515 cltv_expiry_delta: 0,
2516 htlc_minimum_msat: 0,
2517 htlc_maximum_msat: MAX_VALUE_MSAT,
2519 fee_proportional_millionths: 0,
2520 excess_data: Vec::new()
2523 // If all the channels require some features we don't understand, route should fail
2524 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2525 assert_eq!(err, "Failed to find a path to the given destination");
2526 } else { panic!(); }
2528 // If we specify a channel to node7, that overrides our local channel view and that gets used
2529 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2530 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2531 assert_eq!(route.paths[0].len(), 2);
2533 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2534 assert_eq!(route.paths[0][0].short_channel_id, 42);
2535 assert_eq!(route.paths[0][0].fee_msat, 200);
2536 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2537 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2538 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2540 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2541 assert_eq!(route.paths[0][1].short_channel_id, 13);
2542 assert_eq!(route.paths[0][1].fee_msat, 100);
2543 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2544 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2545 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2549 fn disable_node_test() {
2550 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2551 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2552 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2553 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2554 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2555 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2557 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2558 let mut unknown_features = NodeFeatures::empty();
2559 unknown_features.set_unknown_feature_required();
2560 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2561 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2562 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2564 // If all nodes require some features we don't understand, route should fail
2565 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2566 assert_eq!(err, "Failed to find a path to the given destination");
2567 } else { panic!(); }
2569 // If we specify a channel to node7, that overrides our local channel view and that gets used
2570 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2571 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2572 assert_eq!(route.paths[0].len(), 2);
2574 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2575 assert_eq!(route.paths[0][0].short_channel_id, 42);
2576 assert_eq!(route.paths[0][0].fee_msat, 200);
2577 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2578 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2579 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2581 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2582 assert_eq!(route.paths[0][1].short_channel_id, 13);
2583 assert_eq!(route.paths[0][1].fee_msat, 100);
2584 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2585 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2586 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2588 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2589 // naively) assume that the user checked the feature bits on the invoice, which override
2590 // the node_announcement.
2594 fn our_chans_test() {
2595 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2596 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2597 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2598 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2599 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2601 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2602 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2603 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2604 assert_eq!(route.paths[0].len(), 3);
2606 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2607 assert_eq!(route.paths[0][0].short_channel_id, 2);
2608 assert_eq!(route.paths[0][0].fee_msat, 200);
2609 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2610 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2611 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2613 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2614 assert_eq!(route.paths[0][1].short_channel_id, 4);
2615 assert_eq!(route.paths[0][1].fee_msat, 100);
2616 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2617 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2618 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2620 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2621 assert_eq!(route.paths[0][2].short_channel_id, 3);
2622 assert_eq!(route.paths[0][2].fee_msat, 100);
2623 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2624 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2625 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2627 // If we specify a channel to node7, that overrides our local channel view and that gets used
2628 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2629 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2630 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2631 assert_eq!(route.paths[0].len(), 2);
2633 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2634 assert_eq!(route.paths[0][0].short_channel_id, 42);
2635 assert_eq!(route.paths[0][0].fee_msat, 200);
2636 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2637 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2638 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2640 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2641 assert_eq!(route.paths[0][1].short_channel_id, 13);
2642 assert_eq!(route.paths[0][1].fee_msat, 100);
2643 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2644 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2645 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2648 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2649 let zero_fees = RoutingFees {
2651 proportional_millionths: 0,
2653 vec![RouteHint(vec![RouteHintHop {
2654 src_node_id: nodes[3],
2655 short_channel_id: 8,
2657 cltv_expiry_delta: (8 << 4) | 1,
2658 htlc_minimum_msat: None,
2659 htlc_maximum_msat: None,
2661 ]), RouteHint(vec![RouteHintHop {
2662 src_node_id: nodes[4],
2663 short_channel_id: 9,
2666 proportional_millionths: 0,
2668 cltv_expiry_delta: (9 << 4) | 1,
2669 htlc_minimum_msat: None,
2670 htlc_maximum_msat: None,
2671 }]), RouteHint(vec![RouteHintHop {
2672 src_node_id: nodes[5],
2673 short_channel_id: 10,
2675 cltv_expiry_delta: (10 << 4) | 1,
2676 htlc_minimum_msat: None,
2677 htlc_maximum_msat: None,
2681 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2682 let zero_fees = RoutingFees {
2684 proportional_millionths: 0,
2686 vec![RouteHint(vec![RouteHintHop {
2687 src_node_id: nodes[2],
2688 short_channel_id: 5,
2691 proportional_millionths: 0,
2693 cltv_expiry_delta: (5 << 4) | 1,
2694 htlc_minimum_msat: None,
2695 htlc_maximum_msat: None,
2697 src_node_id: nodes[3],
2698 short_channel_id: 8,
2700 cltv_expiry_delta: (8 << 4) | 1,
2701 htlc_minimum_msat: None,
2702 htlc_maximum_msat: None,
2704 ]), RouteHint(vec![RouteHintHop {
2705 src_node_id: nodes[4],
2706 short_channel_id: 9,
2709 proportional_millionths: 0,
2711 cltv_expiry_delta: (9 << 4) | 1,
2712 htlc_minimum_msat: None,
2713 htlc_maximum_msat: None,
2714 }]), RouteHint(vec![RouteHintHop {
2715 src_node_id: nodes[5],
2716 short_channel_id: 10,
2718 cltv_expiry_delta: (10 << 4) | 1,
2719 htlc_minimum_msat: None,
2720 htlc_maximum_msat: None,
2725 fn partial_route_hint_test() {
2726 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2727 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2728 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2729 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2730 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2732 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2733 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2734 // RouteHint may be partially used by the algo to build the best path.
2736 // First check that last hop can't have its source as the payee.
2737 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2738 src_node_id: nodes[6],
2739 short_channel_id: 8,
2742 proportional_millionths: 0,
2744 cltv_expiry_delta: (8 << 4) | 1,
2745 htlc_minimum_msat: None,
2746 htlc_maximum_msat: None,
2749 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2750 invalid_last_hops.push(invalid_last_hop);
2752 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2753 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2754 assert_eq!(err, "Route hint cannot have the payee as the source.");
2755 } else { panic!(); }
2758 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2759 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2760 assert_eq!(route.paths[0].len(), 5);
2762 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2763 assert_eq!(route.paths[0][0].short_channel_id, 2);
2764 assert_eq!(route.paths[0][0].fee_msat, 100);
2765 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2766 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2767 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2769 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2770 assert_eq!(route.paths[0][1].short_channel_id, 4);
2771 assert_eq!(route.paths[0][1].fee_msat, 0);
2772 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2773 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2774 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2776 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2777 assert_eq!(route.paths[0][2].short_channel_id, 6);
2778 assert_eq!(route.paths[0][2].fee_msat, 0);
2779 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2780 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2781 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2783 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2784 assert_eq!(route.paths[0][3].short_channel_id, 11);
2785 assert_eq!(route.paths[0][3].fee_msat, 0);
2786 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2787 // If we have a peer in the node map, we'll use their features here since we don't have
2788 // a way of figuring out their features from the invoice:
2789 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2790 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2792 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2793 assert_eq!(route.paths[0][4].short_channel_id, 8);
2794 assert_eq!(route.paths[0][4].fee_msat, 100);
2795 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2796 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2797 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2800 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2801 let zero_fees = RoutingFees {
2803 proportional_millionths: 0,
2805 vec![RouteHint(vec![RouteHintHop {
2806 src_node_id: nodes[3],
2807 short_channel_id: 8,
2809 cltv_expiry_delta: (8 << 4) | 1,
2810 htlc_minimum_msat: None,
2811 htlc_maximum_msat: None,
2812 }]), RouteHint(vec![
2814 ]), RouteHint(vec![RouteHintHop {
2815 src_node_id: nodes[5],
2816 short_channel_id: 10,
2818 cltv_expiry_delta: (10 << 4) | 1,
2819 htlc_minimum_msat: None,
2820 htlc_maximum_msat: None,
2825 fn ignores_empty_last_hops_test() {
2826 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2827 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2828 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2829 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2830 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2831 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2833 // Test handling of an empty RouteHint passed in Invoice.
2835 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2836 assert_eq!(route.paths[0].len(), 5);
2838 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2839 assert_eq!(route.paths[0][0].short_channel_id, 2);
2840 assert_eq!(route.paths[0][0].fee_msat, 100);
2841 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2842 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2843 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2845 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2846 assert_eq!(route.paths[0][1].short_channel_id, 4);
2847 assert_eq!(route.paths[0][1].fee_msat, 0);
2848 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2849 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2850 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2852 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2853 assert_eq!(route.paths[0][2].short_channel_id, 6);
2854 assert_eq!(route.paths[0][2].fee_msat, 0);
2855 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2856 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2857 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2859 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2860 assert_eq!(route.paths[0][3].short_channel_id, 11);
2861 assert_eq!(route.paths[0][3].fee_msat, 0);
2862 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2863 // If we have a peer in the node map, we'll use their features here since we don't have
2864 // a way of figuring out their features from the invoice:
2865 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2866 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2868 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2869 assert_eq!(route.paths[0][4].short_channel_id, 8);
2870 assert_eq!(route.paths[0][4].fee_msat, 100);
2871 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2872 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2873 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2876 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2878 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2879 let zero_fees = RoutingFees {
2881 proportional_millionths: 0,
2883 vec![RouteHint(vec![RouteHintHop {
2884 src_node_id: hint_hops[0],
2885 short_channel_id: 0xff00,
2888 proportional_millionths: 0,
2890 cltv_expiry_delta: (5 << 4) | 1,
2891 htlc_minimum_msat: None,
2892 htlc_maximum_msat: None,
2894 src_node_id: hint_hops[1],
2895 short_channel_id: 0xff01,
2897 cltv_expiry_delta: (8 << 4) | 1,
2898 htlc_minimum_msat: None,
2899 htlc_maximum_msat: None,
2904 fn multi_hint_last_hops_test() {
2905 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2906 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2907 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2908 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2909 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2910 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2911 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2912 // Test through channels 2, 3, 0xff00, 0xff01.
2913 // Test shows that multiple hop hints are considered.
2915 // Disabling channels 6 & 7 by flags=2
2916 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2917 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2918 short_channel_id: 6,
2920 flags: 2, // to disable
2921 cltv_expiry_delta: 0,
2922 htlc_minimum_msat: 0,
2923 htlc_maximum_msat: MAX_VALUE_MSAT,
2925 fee_proportional_millionths: 0,
2926 excess_data: Vec::new()
2928 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2929 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2930 short_channel_id: 7,
2932 flags: 2, // to disable
2933 cltv_expiry_delta: 0,
2934 htlc_minimum_msat: 0,
2935 htlc_maximum_msat: MAX_VALUE_MSAT,
2937 fee_proportional_millionths: 0,
2938 excess_data: Vec::new()
2941 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2942 assert_eq!(route.paths[0].len(), 4);
2944 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2945 assert_eq!(route.paths[0][0].short_channel_id, 2);
2946 assert_eq!(route.paths[0][0].fee_msat, 200);
2947 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2948 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2949 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2951 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2952 assert_eq!(route.paths[0][1].short_channel_id, 4);
2953 assert_eq!(route.paths[0][1].fee_msat, 100);
2954 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2955 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2956 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2958 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2959 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2960 assert_eq!(route.paths[0][2].fee_msat, 0);
2961 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2962 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2963 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2965 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2966 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2967 assert_eq!(route.paths[0][3].fee_msat, 100);
2968 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2969 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2970 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2974 fn private_multi_hint_last_hops_test() {
2975 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2976 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2978 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
2979 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
2981 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
2982 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2983 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2984 // Test through channels 2, 3, 0xff00, 0xff01.
2985 // Test shows that multiple hop hints are considered.
2987 // Disabling channels 6 & 7 by flags=2
2988 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2989 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2990 short_channel_id: 6,
2992 flags: 2, // to disable
2993 cltv_expiry_delta: 0,
2994 htlc_minimum_msat: 0,
2995 htlc_maximum_msat: MAX_VALUE_MSAT,
2997 fee_proportional_millionths: 0,
2998 excess_data: Vec::new()
3000 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3001 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3002 short_channel_id: 7,
3004 flags: 2, // to disable
3005 cltv_expiry_delta: 0,
3006 htlc_minimum_msat: 0,
3007 htlc_maximum_msat: MAX_VALUE_MSAT,
3009 fee_proportional_millionths: 0,
3010 excess_data: Vec::new()
3013 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3014 assert_eq!(route.paths[0].len(), 4);
3016 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3017 assert_eq!(route.paths[0][0].short_channel_id, 2);
3018 assert_eq!(route.paths[0][0].fee_msat, 200);
3019 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3020 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3021 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3023 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3024 assert_eq!(route.paths[0][1].short_channel_id, 4);
3025 assert_eq!(route.paths[0][1].fee_msat, 100);
3026 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3027 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3028 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3030 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3031 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3032 assert_eq!(route.paths[0][2].fee_msat, 0);
3033 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3034 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3035 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3037 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3038 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3039 assert_eq!(route.paths[0][3].fee_msat, 100);
3040 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3041 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3042 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3045 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3046 let zero_fees = RoutingFees {
3048 proportional_millionths: 0,
3050 vec![RouteHint(vec![RouteHintHop {
3051 src_node_id: nodes[4],
3052 short_channel_id: 11,
3054 cltv_expiry_delta: (11 << 4) | 1,
3055 htlc_minimum_msat: None,
3056 htlc_maximum_msat: None,
3058 src_node_id: nodes[3],
3059 short_channel_id: 8,
3061 cltv_expiry_delta: (8 << 4) | 1,
3062 htlc_minimum_msat: None,
3063 htlc_maximum_msat: None,
3064 }]), RouteHint(vec![RouteHintHop {
3065 src_node_id: nodes[4],
3066 short_channel_id: 9,
3069 proportional_millionths: 0,
3071 cltv_expiry_delta: (9 << 4) | 1,
3072 htlc_minimum_msat: None,
3073 htlc_maximum_msat: None,
3074 }]), RouteHint(vec![RouteHintHop {
3075 src_node_id: nodes[5],
3076 short_channel_id: 10,
3078 cltv_expiry_delta: (10 << 4) | 1,
3079 htlc_minimum_msat: None,
3080 htlc_maximum_msat: None,
3085 fn last_hops_with_public_channel_test() {
3086 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3087 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3088 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3089 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3090 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3091 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3092 // This test shows that public routes can be present in the invoice
3093 // which would be handled in the same manner.
3095 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3096 assert_eq!(route.paths[0].len(), 5);
3098 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3099 assert_eq!(route.paths[0][0].short_channel_id, 2);
3100 assert_eq!(route.paths[0][0].fee_msat, 100);
3101 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3102 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3103 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3105 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3106 assert_eq!(route.paths[0][1].short_channel_id, 4);
3107 assert_eq!(route.paths[0][1].fee_msat, 0);
3108 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3109 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3110 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3112 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3113 assert_eq!(route.paths[0][2].short_channel_id, 6);
3114 assert_eq!(route.paths[0][2].fee_msat, 0);
3115 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3116 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3117 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3119 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3120 assert_eq!(route.paths[0][3].short_channel_id, 11);
3121 assert_eq!(route.paths[0][3].fee_msat, 0);
3122 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3123 // If we have a peer in the node map, we'll use their features here since we don't have
3124 // a way of figuring out their features from the invoice:
3125 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3126 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3128 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3129 assert_eq!(route.paths[0][4].short_channel_id, 8);
3130 assert_eq!(route.paths[0][4].fee_msat, 100);
3131 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3132 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3133 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3137 fn our_chans_last_hop_connect_test() {
3138 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3139 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3140 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3141 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3142 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3144 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3145 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3146 let mut last_hops = last_hops(&nodes);
3147 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3148 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3149 assert_eq!(route.paths[0].len(), 2);
3151 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3152 assert_eq!(route.paths[0][0].short_channel_id, 42);
3153 assert_eq!(route.paths[0][0].fee_msat, 0);
3154 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3155 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3156 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3158 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3159 assert_eq!(route.paths[0][1].short_channel_id, 8);
3160 assert_eq!(route.paths[0][1].fee_msat, 100);
3161 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3162 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3163 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3165 last_hops[0].0[0].fees.base_msat = 1000;
3167 // Revert to via 6 as the fee on 8 goes up
3168 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3169 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3170 assert_eq!(route.paths[0].len(), 4);
3172 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3173 assert_eq!(route.paths[0][0].short_channel_id, 2);
3174 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3175 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3176 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3177 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3179 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3180 assert_eq!(route.paths[0][1].short_channel_id, 4);
3181 assert_eq!(route.paths[0][1].fee_msat, 100);
3182 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3183 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3184 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3186 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3187 assert_eq!(route.paths[0][2].short_channel_id, 7);
3188 assert_eq!(route.paths[0][2].fee_msat, 0);
3189 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3190 // If we have a peer in the node map, we'll use their features here since we don't have
3191 // a way of figuring out their features from the invoice:
3192 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3193 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3195 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3196 assert_eq!(route.paths[0][3].short_channel_id, 10);
3197 assert_eq!(route.paths[0][3].fee_msat, 100);
3198 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3199 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3200 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3202 // ...but still use 8 for larger payments as 6 has a variable feerate
3203 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3204 assert_eq!(route.paths[0].len(), 5);
3206 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3207 assert_eq!(route.paths[0][0].short_channel_id, 2);
3208 assert_eq!(route.paths[0][0].fee_msat, 3000);
3209 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3210 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3211 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3213 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3214 assert_eq!(route.paths[0][1].short_channel_id, 4);
3215 assert_eq!(route.paths[0][1].fee_msat, 0);
3216 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3217 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3218 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3220 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3221 assert_eq!(route.paths[0][2].short_channel_id, 6);
3222 assert_eq!(route.paths[0][2].fee_msat, 0);
3223 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3224 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3225 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3227 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3228 assert_eq!(route.paths[0][3].short_channel_id, 11);
3229 assert_eq!(route.paths[0][3].fee_msat, 1000);
3230 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3231 // If we have a peer in the node map, we'll use their features here since we don't have
3232 // a way of figuring out their features from the invoice:
3233 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3234 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3236 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3237 assert_eq!(route.paths[0][4].short_channel_id, 8);
3238 assert_eq!(route.paths[0][4].fee_msat, 2000);
3239 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3240 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3241 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3244 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> {
3245 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3246 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3247 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3249 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3250 let last_hops = RouteHint(vec![RouteHintHop {
3251 src_node_id: middle_node_id,
3252 short_channel_id: 8,
3255 proportional_millionths: last_hop_fee_prop,
3257 cltv_expiry_delta: (8 << 4) | 1,
3258 htlc_minimum_msat: None,
3259 htlc_maximum_msat: last_hop_htlc_max,
3261 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3262 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3263 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3264 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3265 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3266 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
3267 let logger = ln_test_utils::TestLogger::new();
3268 let network_graph = NetworkGraph::new(genesis_hash, &logger);
3269 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3270 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
3275 fn unannounced_path_test() {
3276 // We should be able to send a payment to a destination without any help of a routing graph
3277 // if we have a channel with a common counterparty that appears in the first and last hop
3279 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3281 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3282 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3283 assert_eq!(route.paths[0].len(), 2);
3285 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3286 assert_eq!(route.paths[0][0].short_channel_id, 42);
3287 assert_eq!(route.paths[0][0].fee_msat, 1001);
3288 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3289 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3290 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3292 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3293 assert_eq!(route.paths[0][1].short_channel_id, 8);
3294 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3295 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3296 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3297 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3301 fn overflow_unannounced_path_test_liquidity_underflow() {
3302 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3303 // the last-hop had a fee which overflowed a u64, we'd panic.
3304 // This was due to us adding the first-hop from us unconditionally, causing us to think
3305 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3306 // In this test, we previously hit a subtraction underflow due to having less available
3307 // liquidity at the last hop than 0.
3308 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());
3312 fn overflow_unannounced_path_test_feerate_overflow() {
3313 // This tests for the same case as above, except instead of hitting a subtraction
3314 // underflow, we hit a case where the fee charged at a hop overflowed.
3315 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());
3319 fn available_amount_while_routing_test() {
3320 // Tests whether we choose the correct available channel amount while routing.
3322 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3323 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3324 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3325 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3326 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3327 let config = UserConfig::default();
3328 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features(&config));
3330 // We will use a simple single-path route from
3331 // our node to node2 via node0: channels {1, 3}.
3333 // First disable all other paths.
3334 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3335 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3336 short_channel_id: 2,
3339 cltv_expiry_delta: 0,
3340 htlc_minimum_msat: 0,
3341 htlc_maximum_msat: 100_000,
3343 fee_proportional_millionths: 0,
3344 excess_data: Vec::new()
3346 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3347 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3348 short_channel_id: 12,
3351 cltv_expiry_delta: 0,
3352 htlc_minimum_msat: 0,
3353 htlc_maximum_msat: 100_000,
3355 fee_proportional_millionths: 0,
3356 excess_data: Vec::new()
3359 // Make the first channel (#1) very permissive,
3360 // and we will be testing all limits on the second channel.
3361 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3362 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3363 short_channel_id: 1,
3366 cltv_expiry_delta: 0,
3367 htlc_minimum_msat: 0,
3368 htlc_maximum_msat: 1_000_000_000,
3370 fee_proportional_millionths: 0,
3371 excess_data: Vec::new()
3374 // First, let's see if routing works if we have absolutely no idea about the available amount.
3375 // In this case, it should be set to 250_000 sats.
3376 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3377 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3378 short_channel_id: 3,
3381 cltv_expiry_delta: 0,
3382 htlc_minimum_msat: 0,
3383 htlc_maximum_msat: 250_000_000,
3385 fee_proportional_millionths: 0,
3386 excess_data: Vec::new()
3390 // Attempt to route more than available results in a failure.
3391 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3392 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3393 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3394 } else { panic!(); }
3398 // Now, attempt to route an exact amount we have should be fine.
3399 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3400 assert_eq!(route.paths.len(), 1);
3401 let path = route.paths.last().unwrap();
3402 assert_eq!(path.len(), 2);
3403 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3404 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3407 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3408 // Disable channel #1 and use another first hop.
3409 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3410 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3411 short_channel_id: 1,
3414 cltv_expiry_delta: 0,
3415 htlc_minimum_msat: 0,
3416 htlc_maximum_msat: 1_000_000_000,
3418 fee_proportional_millionths: 0,
3419 excess_data: Vec::new()
3422 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3423 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3426 // Attempt to route more than available results in a failure.
3427 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3428 &our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3429 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3430 } else { panic!(); }
3434 // Now, attempt to route an exact amount we have should be fine.
3435 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3436 assert_eq!(route.paths.len(), 1);
3437 let path = route.paths.last().unwrap();
3438 assert_eq!(path.len(), 2);
3439 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3440 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3443 // Enable channel #1 back.
3444 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3445 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3446 short_channel_id: 1,
3449 cltv_expiry_delta: 0,
3450 htlc_minimum_msat: 0,
3451 htlc_maximum_msat: 1_000_000_000,
3453 fee_proportional_millionths: 0,
3454 excess_data: Vec::new()
3458 // Now let's see if routing works if we know only htlc_maximum_msat.
3459 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3460 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3461 short_channel_id: 3,
3464 cltv_expiry_delta: 0,
3465 htlc_minimum_msat: 0,
3466 htlc_maximum_msat: 15_000,
3468 fee_proportional_millionths: 0,
3469 excess_data: Vec::new()
3473 // Attempt to route more than available results in a failure.
3474 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3475 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3476 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3477 } else { panic!(); }
3481 // Now, attempt to route an exact amount we have should be fine.
3482 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3483 assert_eq!(route.paths.len(), 1);
3484 let path = route.paths.last().unwrap();
3485 assert_eq!(path.len(), 2);
3486 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3487 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3490 // Now let's see if routing works if we know only capacity from the UTXO.
3492 // We can't change UTXO capacity on the fly, so we'll disable
3493 // the existing channel and add another one with the capacity we need.
3494 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3495 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3496 short_channel_id: 3,
3499 cltv_expiry_delta: 0,
3500 htlc_minimum_msat: 0,
3501 htlc_maximum_msat: MAX_VALUE_MSAT,
3503 fee_proportional_millionths: 0,
3504 excess_data: Vec::new()
3507 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3508 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3509 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3510 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3511 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3513 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3514 gossip_sync.add_chain_access(Some(chain_monitor));
3516 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3517 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3518 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3519 short_channel_id: 333,
3522 cltv_expiry_delta: (3 << 4) | 1,
3523 htlc_minimum_msat: 0,
3524 htlc_maximum_msat: 15_000,
3526 fee_proportional_millionths: 0,
3527 excess_data: Vec::new()
3529 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3530 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3531 short_channel_id: 333,
3534 cltv_expiry_delta: (3 << 4) | 2,
3535 htlc_minimum_msat: 0,
3536 htlc_maximum_msat: 15_000,
3538 fee_proportional_millionths: 0,
3539 excess_data: Vec::new()
3543 // Attempt to route more than available results in a failure.
3544 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3545 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3546 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3547 } else { panic!(); }
3551 // Now, attempt to route an exact amount we have should be fine.
3552 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3553 assert_eq!(route.paths.len(), 1);
3554 let path = route.paths.last().unwrap();
3555 assert_eq!(path.len(), 2);
3556 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3557 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3560 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3561 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3562 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3563 short_channel_id: 333,
3566 cltv_expiry_delta: 0,
3567 htlc_minimum_msat: 0,
3568 htlc_maximum_msat: 10_000,
3570 fee_proportional_millionths: 0,
3571 excess_data: Vec::new()
3575 // Attempt to route more than available results in a failure.
3576 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3577 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3578 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3579 } else { panic!(); }
3583 // Now, attempt to route an exact amount we have should be fine.
3584 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3585 assert_eq!(route.paths.len(), 1);
3586 let path = route.paths.last().unwrap();
3587 assert_eq!(path.len(), 2);
3588 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3589 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3594 fn available_liquidity_last_hop_test() {
3595 // Check that available liquidity properly limits the path even when only
3596 // one of the latter hops is limited.
3597 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3598 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3599 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3600 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3601 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3602 let config = UserConfig::default();
3603 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features(&config));
3605 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3606 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3607 // Total capacity: 50 sats.
3609 // Disable other potential paths.
3610 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3611 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3612 short_channel_id: 2,
3615 cltv_expiry_delta: 0,
3616 htlc_minimum_msat: 0,
3617 htlc_maximum_msat: 100_000,
3619 fee_proportional_millionths: 0,
3620 excess_data: Vec::new()
3622 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3624 short_channel_id: 7,
3627 cltv_expiry_delta: 0,
3628 htlc_minimum_msat: 0,
3629 htlc_maximum_msat: 100_000,
3631 fee_proportional_millionths: 0,
3632 excess_data: Vec::new()
3637 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3638 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3639 short_channel_id: 12,
3642 cltv_expiry_delta: 0,
3643 htlc_minimum_msat: 0,
3644 htlc_maximum_msat: 100_000,
3646 fee_proportional_millionths: 0,
3647 excess_data: Vec::new()
3649 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3650 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3651 short_channel_id: 13,
3654 cltv_expiry_delta: 0,
3655 htlc_minimum_msat: 0,
3656 htlc_maximum_msat: 100_000,
3658 fee_proportional_millionths: 0,
3659 excess_data: Vec::new()
3662 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3663 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3664 short_channel_id: 6,
3667 cltv_expiry_delta: 0,
3668 htlc_minimum_msat: 0,
3669 htlc_maximum_msat: 50_000,
3671 fee_proportional_millionths: 0,
3672 excess_data: Vec::new()
3674 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3675 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3676 short_channel_id: 11,
3679 cltv_expiry_delta: 0,
3680 htlc_minimum_msat: 0,
3681 htlc_maximum_msat: 100_000,
3683 fee_proportional_millionths: 0,
3684 excess_data: Vec::new()
3687 // Attempt to route more than available results in a failure.
3688 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3689 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3690 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3691 } else { panic!(); }
3695 // Now, attempt to route 49 sats (just a bit below the capacity).
3696 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3697 assert_eq!(route.paths.len(), 1);
3698 let mut total_amount_paid_msat = 0;
3699 for path in &route.paths {
3700 assert_eq!(path.len(), 4);
3701 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3702 total_amount_paid_msat += path.last().unwrap().fee_msat;
3704 assert_eq!(total_amount_paid_msat, 49_000);
3708 // Attempt to route an exact amount is also fine
3709 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3710 assert_eq!(route.paths.len(), 1);
3711 let mut total_amount_paid_msat = 0;
3712 for path in &route.paths {
3713 assert_eq!(path.len(), 4);
3714 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3715 total_amount_paid_msat += path.last().unwrap().fee_msat;
3717 assert_eq!(total_amount_paid_msat, 50_000);
3722 fn ignore_fee_first_hop_test() {
3723 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3724 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3725 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3726 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3727 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3728 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3730 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3731 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3732 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3733 short_channel_id: 1,
3736 cltv_expiry_delta: 0,
3737 htlc_minimum_msat: 0,
3738 htlc_maximum_msat: 100_000,
3739 fee_base_msat: 1_000_000,
3740 fee_proportional_millionths: 0,
3741 excess_data: Vec::new()
3743 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3744 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3745 short_channel_id: 3,
3748 cltv_expiry_delta: 0,
3749 htlc_minimum_msat: 0,
3750 htlc_maximum_msat: 50_000,
3752 fee_proportional_millionths: 0,
3753 excess_data: Vec::new()
3757 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3758 assert_eq!(route.paths.len(), 1);
3759 let mut total_amount_paid_msat = 0;
3760 for path in &route.paths {
3761 assert_eq!(path.len(), 2);
3762 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3763 total_amount_paid_msat += path.last().unwrap().fee_msat;
3765 assert_eq!(total_amount_paid_msat, 50_000);
3770 fn simple_mpp_route_test() {
3771 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3772 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3773 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3774 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3775 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3776 let config = UserConfig::default();
3777 let payment_params = PaymentParameters::from_node_id(nodes[2])
3778 .with_features(channelmanager::provided_invoice_features(&config));
3780 // We need a route consisting of 3 paths:
3781 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3782 // To achieve this, the amount being transferred should be around
3783 // the total capacity of these 3 paths.
3785 // First, we set limits on these (previously unlimited) channels.
3786 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3788 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3789 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3790 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3791 short_channel_id: 1,
3794 cltv_expiry_delta: 0,
3795 htlc_minimum_msat: 0,
3796 htlc_maximum_msat: 100_000,
3798 fee_proportional_millionths: 0,
3799 excess_data: Vec::new()
3801 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3802 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3803 short_channel_id: 3,
3806 cltv_expiry_delta: 0,
3807 htlc_minimum_msat: 0,
3808 htlc_maximum_msat: 50_000,
3810 fee_proportional_millionths: 0,
3811 excess_data: Vec::new()
3814 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3815 // (total limit 60).
3816 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3817 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3818 short_channel_id: 12,
3821 cltv_expiry_delta: 0,
3822 htlc_minimum_msat: 0,
3823 htlc_maximum_msat: 60_000,
3825 fee_proportional_millionths: 0,
3826 excess_data: Vec::new()
3828 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3829 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3830 short_channel_id: 13,
3833 cltv_expiry_delta: 0,
3834 htlc_minimum_msat: 0,
3835 htlc_maximum_msat: 60_000,
3837 fee_proportional_millionths: 0,
3838 excess_data: Vec::new()
3841 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3842 // (total capacity 180 sats).
3843 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3844 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3845 short_channel_id: 2,
3848 cltv_expiry_delta: 0,
3849 htlc_minimum_msat: 0,
3850 htlc_maximum_msat: 200_000,
3852 fee_proportional_millionths: 0,
3853 excess_data: Vec::new()
3855 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3856 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3857 short_channel_id: 4,
3860 cltv_expiry_delta: 0,
3861 htlc_minimum_msat: 0,
3862 htlc_maximum_msat: 180_000,
3864 fee_proportional_millionths: 0,
3865 excess_data: Vec::new()
3869 // Attempt to route more than available results in a failure.
3870 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3871 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42,
3872 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3873 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3874 } else { panic!(); }
3878 // Attempt to route while setting max_path_count to 0 results in a failure.
3879 let zero_payment_params = payment_params.clone().with_max_path_count(0);
3880 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3881 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100, 42,
3882 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3883 assert_eq!(err, "Can't find a route with no paths allowed.");
3884 } else { panic!(); }
3888 // Attempt to route while setting max_path_count to 3 results in a failure.
3889 // This is the case because the minimal_value_contribution_msat would require each path
3890 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
3891 let fail_payment_params = payment_params.clone().with_max_path_count(3);
3892 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3893 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000, 42,
3894 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3895 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3896 } else { panic!(); }
3900 // Now, attempt to route 250 sats (just a bit below the capacity).
3901 // Our algorithm should provide us with these 3 paths.
3902 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3903 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3904 assert_eq!(route.paths.len(), 3);
3905 let mut total_amount_paid_msat = 0;
3906 for path in &route.paths {
3907 assert_eq!(path.len(), 2);
3908 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3909 total_amount_paid_msat += path.last().unwrap().fee_msat;
3911 assert_eq!(total_amount_paid_msat, 250_000);
3915 // Attempt to route an exact amount is also fine
3916 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3917 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3918 assert_eq!(route.paths.len(), 3);
3919 let mut total_amount_paid_msat = 0;
3920 for path in &route.paths {
3921 assert_eq!(path.len(), 2);
3922 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3923 total_amount_paid_msat += path.last().unwrap().fee_msat;
3925 assert_eq!(total_amount_paid_msat, 290_000);
3930 fn long_mpp_route_test() {
3931 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3932 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3933 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3934 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3935 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3936 let config = UserConfig::default();
3937 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features(&config));
3939 // We need a route consisting of 3 paths:
3940 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3941 // Note that these paths overlap (channels 5, 12, 13).
3942 // We will route 300 sats.
3943 // Each path will have 100 sats capacity, those channels which
3944 // are used twice will have 200 sats capacity.
3946 // Disable other potential paths.
3947 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3948 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3949 short_channel_id: 2,
3952 cltv_expiry_delta: 0,
3953 htlc_minimum_msat: 0,
3954 htlc_maximum_msat: 100_000,
3956 fee_proportional_millionths: 0,
3957 excess_data: Vec::new()
3959 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3960 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3961 short_channel_id: 7,
3964 cltv_expiry_delta: 0,
3965 htlc_minimum_msat: 0,
3966 htlc_maximum_msat: 100_000,
3968 fee_proportional_millionths: 0,
3969 excess_data: Vec::new()
3972 // Path via {node0, node2} is channels {1, 3, 5}.
3973 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3974 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3975 short_channel_id: 1,
3978 cltv_expiry_delta: 0,
3979 htlc_minimum_msat: 0,
3980 htlc_maximum_msat: 100_000,
3982 fee_proportional_millionths: 0,
3983 excess_data: Vec::new()
3985 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3986 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3987 short_channel_id: 3,
3990 cltv_expiry_delta: 0,
3991 htlc_minimum_msat: 0,
3992 htlc_maximum_msat: 100_000,
3994 fee_proportional_millionths: 0,
3995 excess_data: Vec::new()
3998 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3999 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4000 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4001 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4002 short_channel_id: 5,
4005 cltv_expiry_delta: 0,
4006 htlc_minimum_msat: 0,
4007 htlc_maximum_msat: 200_000,
4009 fee_proportional_millionths: 0,
4010 excess_data: Vec::new()
4013 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4014 // Add 100 sats to the capacities of {12, 13}, because these channels
4015 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4016 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4017 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4018 short_channel_id: 12,
4021 cltv_expiry_delta: 0,
4022 htlc_minimum_msat: 0,
4023 htlc_maximum_msat: 200_000,
4025 fee_proportional_millionths: 0,
4026 excess_data: Vec::new()
4028 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4029 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4030 short_channel_id: 13,
4033 cltv_expiry_delta: 0,
4034 htlc_minimum_msat: 0,
4035 htlc_maximum_msat: 200_000,
4037 fee_proportional_millionths: 0,
4038 excess_data: Vec::new()
4041 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4042 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4043 short_channel_id: 6,
4046 cltv_expiry_delta: 0,
4047 htlc_minimum_msat: 0,
4048 htlc_maximum_msat: 100_000,
4050 fee_proportional_millionths: 0,
4051 excess_data: Vec::new()
4053 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4054 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4055 short_channel_id: 11,
4058 cltv_expiry_delta: 0,
4059 htlc_minimum_msat: 0,
4060 htlc_maximum_msat: 100_000,
4062 fee_proportional_millionths: 0,
4063 excess_data: Vec::new()
4066 // Path via {node7, node2} is channels {12, 13, 5}.
4067 // We already limited them to 200 sats (they are used twice for 100 sats).
4068 // Nothing to do here.
4071 // Attempt to route more than available results in a failure.
4072 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4073 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4074 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4075 } else { panic!(); }
4079 // Now, attempt to route 300 sats (exact amount we can route).
4080 // Our algorithm should provide us with these 3 paths, 100 sats each.
4081 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4082 assert_eq!(route.paths.len(), 3);
4084 let mut total_amount_paid_msat = 0;
4085 for path in &route.paths {
4086 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4087 total_amount_paid_msat += path.last().unwrap().fee_msat;
4089 assert_eq!(total_amount_paid_msat, 300_000);
4095 fn mpp_cheaper_route_test() {
4096 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4097 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4098 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4099 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4100 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4101 let config = UserConfig::default();
4102 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features(&config));
4104 // This test checks that if we have two cheaper paths and one more expensive path,
4105 // so that liquidity-wise any 2 of 3 combination is sufficient,
4106 // two cheaper paths will be taken.
4107 // These paths have equal available liquidity.
4109 // We need a combination of 3 paths:
4110 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4111 // Note that these paths overlap (channels 5, 12, 13).
4112 // Each path will have 100 sats capacity, those channels which
4113 // are used twice will have 200 sats capacity.
4115 // Disable other potential paths.
4116 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4117 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4118 short_channel_id: 2,
4121 cltv_expiry_delta: 0,
4122 htlc_minimum_msat: 0,
4123 htlc_maximum_msat: 100_000,
4125 fee_proportional_millionths: 0,
4126 excess_data: Vec::new()
4128 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4129 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4130 short_channel_id: 7,
4133 cltv_expiry_delta: 0,
4134 htlc_minimum_msat: 0,
4135 htlc_maximum_msat: 100_000,
4137 fee_proportional_millionths: 0,
4138 excess_data: Vec::new()
4141 // Path via {node0, node2} is channels {1, 3, 5}.
4142 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4144 short_channel_id: 1,
4147 cltv_expiry_delta: 0,
4148 htlc_minimum_msat: 0,
4149 htlc_maximum_msat: 100_000,
4151 fee_proportional_millionths: 0,
4152 excess_data: Vec::new()
4154 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4156 short_channel_id: 3,
4159 cltv_expiry_delta: 0,
4160 htlc_minimum_msat: 0,
4161 htlc_maximum_msat: 100_000,
4163 fee_proportional_millionths: 0,
4164 excess_data: Vec::new()
4167 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4168 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4169 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4170 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4171 short_channel_id: 5,
4174 cltv_expiry_delta: 0,
4175 htlc_minimum_msat: 0,
4176 htlc_maximum_msat: 200_000,
4178 fee_proportional_millionths: 0,
4179 excess_data: Vec::new()
4182 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4183 // Add 100 sats to the capacities of {12, 13}, because these channels
4184 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4185 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4186 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4187 short_channel_id: 12,
4190 cltv_expiry_delta: 0,
4191 htlc_minimum_msat: 0,
4192 htlc_maximum_msat: 200_000,
4194 fee_proportional_millionths: 0,
4195 excess_data: Vec::new()
4197 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4198 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4199 short_channel_id: 13,
4202 cltv_expiry_delta: 0,
4203 htlc_minimum_msat: 0,
4204 htlc_maximum_msat: 200_000,
4206 fee_proportional_millionths: 0,
4207 excess_data: Vec::new()
4210 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4211 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4212 short_channel_id: 6,
4215 cltv_expiry_delta: 0,
4216 htlc_minimum_msat: 0,
4217 htlc_maximum_msat: 100_000,
4218 fee_base_msat: 1_000,
4219 fee_proportional_millionths: 0,
4220 excess_data: Vec::new()
4222 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4223 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4224 short_channel_id: 11,
4227 cltv_expiry_delta: 0,
4228 htlc_minimum_msat: 0,
4229 htlc_maximum_msat: 100_000,
4231 fee_proportional_millionths: 0,
4232 excess_data: Vec::new()
4235 // Path via {node7, node2} is channels {12, 13, 5}.
4236 // We already limited them to 200 sats (they are used twice for 100 sats).
4237 // Nothing to do here.
4240 // Now, attempt to route 180 sats.
4241 // Our algorithm should provide us with these 2 paths.
4242 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4243 assert_eq!(route.paths.len(), 2);
4245 let mut total_value_transferred_msat = 0;
4246 let mut total_paid_msat = 0;
4247 for path in &route.paths {
4248 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4249 total_value_transferred_msat += path.last().unwrap().fee_msat;
4251 total_paid_msat += hop.fee_msat;
4254 // If we paid fee, this would be higher.
4255 assert_eq!(total_value_transferred_msat, 180_000);
4256 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4257 assert_eq!(total_fees_paid, 0);
4262 fn fees_on_mpp_route_test() {
4263 // This test makes sure that MPP algorithm properly takes into account
4264 // fees charged on the channels, by making the fees impactful:
4265 // if the fee is not properly accounted for, the behavior is different.
4266 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4267 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4268 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4269 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4270 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4271 let config = UserConfig::default();
4272 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features(&config));
4274 // We need a route consisting of 2 paths:
4275 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4276 // We will route 200 sats, Each path will have 100 sats capacity.
4278 // This test is not particularly stable: e.g.,
4279 // there's a way to route via {node0, node2, node4}.
4280 // It works while pathfinding is deterministic, but can be broken otherwise.
4281 // It's fine to ignore this concern for now.
4283 // Disable other potential paths.
4284 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4285 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4286 short_channel_id: 2,
4289 cltv_expiry_delta: 0,
4290 htlc_minimum_msat: 0,
4291 htlc_maximum_msat: 100_000,
4293 fee_proportional_millionths: 0,
4294 excess_data: Vec::new()
4297 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4298 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4299 short_channel_id: 7,
4302 cltv_expiry_delta: 0,
4303 htlc_minimum_msat: 0,
4304 htlc_maximum_msat: 100_000,
4306 fee_proportional_millionths: 0,
4307 excess_data: Vec::new()
4310 // Path via {node0, node2} is channels {1, 3, 5}.
4311 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4312 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4313 short_channel_id: 1,
4316 cltv_expiry_delta: 0,
4317 htlc_minimum_msat: 0,
4318 htlc_maximum_msat: 100_000,
4320 fee_proportional_millionths: 0,
4321 excess_data: Vec::new()
4323 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4324 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4325 short_channel_id: 3,
4328 cltv_expiry_delta: 0,
4329 htlc_minimum_msat: 0,
4330 htlc_maximum_msat: 100_000,
4332 fee_proportional_millionths: 0,
4333 excess_data: Vec::new()
4336 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4337 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4338 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4339 short_channel_id: 5,
4342 cltv_expiry_delta: 0,
4343 htlc_minimum_msat: 0,
4344 htlc_maximum_msat: 100_000,
4346 fee_proportional_millionths: 0,
4347 excess_data: Vec::new()
4350 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4351 // All channels should be 100 sats capacity. But for the fee experiment,
4352 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4353 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4354 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4355 // so no matter how large are other channels,
4356 // the whole path will be limited by 100 sats with just these 2 conditions:
4357 // - channel 12 capacity is 250 sats
4358 // - fee for channel 6 is 150 sats
4359 // Let's test this by enforcing these 2 conditions and removing other limits.
4360 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4361 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4362 short_channel_id: 12,
4365 cltv_expiry_delta: 0,
4366 htlc_minimum_msat: 0,
4367 htlc_maximum_msat: 250_000,
4369 fee_proportional_millionths: 0,
4370 excess_data: Vec::new()
4372 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4373 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4374 short_channel_id: 13,
4377 cltv_expiry_delta: 0,
4378 htlc_minimum_msat: 0,
4379 htlc_maximum_msat: MAX_VALUE_MSAT,
4381 fee_proportional_millionths: 0,
4382 excess_data: Vec::new()
4385 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4386 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4387 short_channel_id: 6,
4390 cltv_expiry_delta: 0,
4391 htlc_minimum_msat: 0,
4392 htlc_maximum_msat: MAX_VALUE_MSAT,
4393 fee_base_msat: 150_000,
4394 fee_proportional_millionths: 0,
4395 excess_data: Vec::new()
4397 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4398 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4399 short_channel_id: 11,
4402 cltv_expiry_delta: 0,
4403 htlc_minimum_msat: 0,
4404 htlc_maximum_msat: MAX_VALUE_MSAT,
4406 fee_proportional_millionths: 0,
4407 excess_data: Vec::new()
4411 // Attempt to route more than available results in a failure.
4412 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4413 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4414 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4415 } else { panic!(); }
4419 // Now, attempt to route 200 sats (exact amount we can route).
4420 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4421 assert_eq!(route.paths.len(), 2);
4423 let mut total_amount_paid_msat = 0;
4424 for path in &route.paths {
4425 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4426 total_amount_paid_msat += path.last().unwrap().fee_msat;
4428 assert_eq!(total_amount_paid_msat, 200_000);
4429 assert_eq!(route.get_total_fees(), 150_000);
4434 fn mpp_with_last_hops() {
4435 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4436 // via a single last-hop route hint, we'd fail to route if we first collected routes
4437 // totaling close but not quite enough to fund the full payment.
4439 // This was because we considered last-hop hints to have exactly the sought payment amount
4440 // instead of the amount we were trying to collect, needlessly limiting our path searching
4441 // at the very first hop.
4443 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4444 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4445 // to only have the remaining to-collect amount in available liquidity.
4447 // This bug appeared in production in some specific channel configurations.
4448 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4449 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4450 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4451 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4452 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4453 let config = UserConfig::default();
4454 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(channelmanager::provided_invoice_features(&config))
4455 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4456 src_node_id: nodes[2],
4457 short_channel_id: 42,
4458 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4459 cltv_expiry_delta: 42,
4460 htlc_minimum_msat: None,
4461 htlc_maximum_msat: None,
4462 }])]).with_max_channel_saturation_power_of_half(0);
4464 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4465 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4466 // would first use the no-fee route and then fail to find a path along the second route as
4467 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4468 // under 5% of our payment amount.
4469 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4471 short_channel_id: 1,
4474 cltv_expiry_delta: (5 << 4) | 5,
4475 htlc_minimum_msat: 0,
4476 htlc_maximum_msat: 99_000,
4477 fee_base_msat: u32::max_value(),
4478 fee_proportional_millionths: u32::max_value(),
4479 excess_data: Vec::new()
4481 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4482 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4483 short_channel_id: 2,
4486 cltv_expiry_delta: (5 << 4) | 3,
4487 htlc_minimum_msat: 0,
4488 htlc_maximum_msat: 99_000,
4489 fee_base_msat: u32::max_value(),
4490 fee_proportional_millionths: u32::max_value(),
4491 excess_data: Vec::new()
4493 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4494 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4495 short_channel_id: 4,
4498 cltv_expiry_delta: (4 << 4) | 1,
4499 htlc_minimum_msat: 0,
4500 htlc_maximum_msat: MAX_VALUE_MSAT,
4502 fee_proportional_millionths: 0,
4503 excess_data: Vec::new()
4505 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4506 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4507 short_channel_id: 13,
4509 flags: 0|2, // Channel disabled
4510 cltv_expiry_delta: (13 << 4) | 1,
4511 htlc_minimum_msat: 0,
4512 htlc_maximum_msat: MAX_VALUE_MSAT,
4514 fee_proportional_millionths: 2000000,
4515 excess_data: Vec::new()
4518 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4520 let mut route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4521 assert_eq!(route.paths.len(), 2);
4522 route.paths.sort_by_key(|path| path[0].short_channel_id);
4523 // Paths are manually ordered ordered by SCID, so:
4524 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4525 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4526 assert_eq!(route.paths[0][0].short_channel_id, 1);
4527 assert_eq!(route.paths[0][0].fee_msat, 0);
4528 assert_eq!(route.paths[0][2].fee_msat, 99_000);
4529 assert_eq!(route.paths[1][0].short_channel_id, 2);
4530 assert_eq!(route.paths[1][0].fee_msat, 1);
4531 assert_eq!(route.paths[1][2].fee_msat, 1_000);
4532 assert_eq!(route.get_total_fees(), 1);
4533 assert_eq!(route.get_total_amount(), 100_000);
4537 fn drop_lowest_channel_mpp_route_test() {
4538 // This test checks that low-capacity channel is dropped when after
4539 // path finding we realize that we found more capacity than we need.
4540 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4541 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4542 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4543 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4544 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4545 let config = UserConfig::default();
4546 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features(&config))
4547 .with_max_channel_saturation_power_of_half(0);
4549 // We need a route consisting of 3 paths:
4550 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4552 // The first and the second paths should be sufficient, but the third should be
4553 // cheaper, so that we select it but drop later.
4555 // First, we set limits on these (previously unlimited) channels.
4556 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4558 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4559 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4560 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4561 short_channel_id: 1,
4564 cltv_expiry_delta: 0,
4565 htlc_minimum_msat: 0,
4566 htlc_maximum_msat: 100_000,
4568 fee_proportional_millionths: 0,
4569 excess_data: Vec::new()
4571 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4572 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4573 short_channel_id: 3,
4576 cltv_expiry_delta: 0,
4577 htlc_minimum_msat: 0,
4578 htlc_maximum_msat: 50_000,
4580 fee_proportional_millionths: 0,
4581 excess_data: Vec::new()
4584 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4585 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4586 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4587 short_channel_id: 12,
4590 cltv_expiry_delta: 0,
4591 htlc_minimum_msat: 0,
4592 htlc_maximum_msat: 60_000,
4594 fee_proportional_millionths: 0,
4595 excess_data: Vec::new()
4597 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4598 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4599 short_channel_id: 13,
4602 cltv_expiry_delta: 0,
4603 htlc_minimum_msat: 0,
4604 htlc_maximum_msat: 60_000,
4606 fee_proportional_millionths: 0,
4607 excess_data: Vec::new()
4610 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4611 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4612 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4613 short_channel_id: 2,
4616 cltv_expiry_delta: 0,
4617 htlc_minimum_msat: 0,
4618 htlc_maximum_msat: 20_000,
4620 fee_proportional_millionths: 0,
4621 excess_data: Vec::new()
4623 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4624 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4625 short_channel_id: 4,
4628 cltv_expiry_delta: 0,
4629 htlc_minimum_msat: 0,
4630 htlc_maximum_msat: 20_000,
4632 fee_proportional_millionths: 0,
4633 excess_data: Vec::new()
4637 // Attempt to route more than available results in a failure.
4638 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4639 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4640 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4641 } else { panic!(); }
4645 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4646 // Our algorithm should provide us with these 3 paths.
4647 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4648 assert_eq!(route.paths.len(), 3);
4649 let mut total_amount_paid_msat = 0;
4650 for path in &route.paths {
4651 assert_eq!(path.len(), 2);
4652 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4653 total_amount_paid_msat += path.last().unwrap().fee_msat;
4655 assert_eq!(total_amount_paid_msat, 125_000);
4659 // Attempt to route without the last small cheap channel
4660 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4661 assert_eq!(route.paths.len(), 2);
4662 let mut total_amount_paid_msat = 0;
4663 for path in &route.paths {
4664 assert_eq!(path.len(), 2);
4665 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4666 total_amount_paid_msat += path.last().unwrap().fee_msat;
4668 assert_eq!(total_amount_paid_msat, 90_000);
4673 fn min_criteria_consistency() {
4674 // Test that we don't use an inconsistent metric between updating and walking nodes during
4675 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4676 // was updated with a different criterion from the heap sorting, resulting in loops in
4677 // calculated paths. We test for that specific case here.
4679 // We construct a network that looks like this:
4681 // node2 -1(3)2- node3
4685 // node1 -1(5)2- node4 -1(1)2- node6
4691 // We create a loop on the side of our real path - our destination is node 6, with a
4692 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4693 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4694 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4695 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4696 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4697 // "previous hop" being set to node 3, creating a loop in the path.
4698 let secp_ctx = Secp256k1::new();
4699 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4700 let logger = Arc::new(ln_test_utils::TestLogger::new());
4701 let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
4702 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
4703 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4704 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4705 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4706 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4707 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4709 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4710 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4711 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4712 short_channel_id: 6,
4715 cltv_expiry_delta: (6 << 4) | 0,
4716 htlc_minimum_msat: 0,
4717 htlc_maximum_msat: MAX_VALUE_MSAT,
4719 fee_proportional_millionths: 0,
4720 excess_data: Vec::new()
4722 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4724 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4725 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4726 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4727 short_channel_id: 5,
4730 cltv_expiry_delta: (5 << 4) | 0,
4731 htlc_minimum_msat: 0,
4732 htlc_maximum_msat: MAX_VALUE_MSAT,
4734 fee_proportional_millionths: 0,
4735 excess_data: Vec::new()
4737 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4739 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4740 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4741 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4742 short_channel_id: 4,
4745 cltv_expiry_delta: (4 << 4) | 0,
4746 htlc_minimum_msat: 0,
4747 htlc_maximum_msat: MAX_VALUE_MSAT,
4749 fee_proportional_millionths: 0,
4750 excess_data: Vec::new()
4752 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4754 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4755 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4756 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4757 short_channel_id: 3,
4760 cltv_expiry_delta: (3 << 4) | 0,
4761 htlc_minimum_msat: 0,
4762 htlc_maximum_msat: MAX_VALUE_MSAT,
4764 fee_proportional_millionths: 0,
4765 excess_data: Vec::new()
4767 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4769 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4770 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4771 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4772 short_channel_id: 2,
4775 cltv_expiry_delta: (2 << 4) | 0,
4776 htlc_minimum_msat: 0,
4777 htlc_maximum_msat: MAX_VALUE_MSAT,
4779 fee_proportional_millionths: 0,
4780 excess_data: Vec::new()
4783 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4784 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4785 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4786 short_channel_id: 1,
4789 cltv_expiry_delta: (1 << 4) | 0,
4790 htlc_minimum_msat: 100,
4791 htlc_maximum_msat: MAX_VALUE_MSAT,
4793 fee_proportional_millionths: 0,
4794 excess_data: Vec::new()
4796 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4799 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4800 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4801 assert_eq!(route.paths.len(), 1);
4802 assert_eq!(route.paths[0].len(), 3);
4804 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4805 assert_eq!(route.paths[0][0].short_channel_id, 6);
4806 assert_eq!(route.paths[0][0].fee_msat, 100);
4807 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4808 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4809 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4811 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4812 assert_eq!(route.paths[0][1].short_channel_id, 5);
4813 assert_eq!(route.paths[0][1].fee_msat, 0);
4814 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4815 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4816 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4818 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4819 assert_eq!(route.paths[0][2].short_channel_id, 1);
4820 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4821 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4822 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4823 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4829 fn exact_fee_liquidity_limit() {
4830 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4831 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4832 // we calculated fees on a higher value, resulting in us ignoring such paths.
4833 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4834 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4835 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4836 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4837 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4838 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4840 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4842 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4843 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4844 short_channel_id: 2,
4847 cltv_expiry_delta: 0,
4848 htlc_minimum_msat: 0,
4849 htlc_maximum_msat: 85_000,
4851 fee_proportional_millionths: 0,
4852 excess_data: Vec::new()
4855 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4856 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4857 short_channel_id: 12,
4860 cltv_expiry_delta: (4 << 4) | 1,
4861 htlc_minimum_msat: 0,
4862 htlc_maximum_msat: 270_000,
4864 fee_proportional_millionths: 1000000,
4865 excess_data: Vec::new()
4869 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4870 // 200% fee charged channel 13 in the 1-to-2 direction.
4871 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4872 assert_eq!(route.paths.len(), 1);
4873 assert_eq!(route.paths[0].len(), 2);
4875 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4876 assert_eq!(route.paths[0][0].short_channel_id, 12);
4877 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4878 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4879 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4880 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4882 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4883 assert_eq!(route.paths[0][1].short_channel_id, 13);
4884 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4885 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4886 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4887 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4892 fn htlc_max_reduction_below_min() {
4893 // Test that if, while walking the graph, we reduce the value being sent to meet an
4894 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4895 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4896 // resulting in us thinking there is no possible path, even if other paths exist.
4897 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4898 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4899 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4900 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4901 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4902 let config = UserConfig::default();
4903 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features(&config));
4905 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4906 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4907 // then try to send 90_000.
4908 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4909 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4910 short_channel_id: 2,
4913 cltv_expiry_delta: 0,
4914 htlc_minimum_msat: 0,
4915 htlc_maximum_msat: 80_000,
4917 fee_proportional_millionths: 0,
4918 excess_data: Vec::new()
4920 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4921 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4922 short_channel_id: 4,
4925 cltv_expiry_delta: (4 << 4) | 1,
4926 htlc_minimum_msat: 90_000,
4927 htlc_maximum_msat: MAX_VALUE_MSAT,
4929 fee_proportional_millionths: 0,
4930 excess_data: Vec::new()
4934 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4935 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4936 // expensive) channels 12-13 path.
4937 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4938 assert_eq!(route.paths.len(), 1);
4939 assert_eq!(route.paths[0].len(), 2);
4941 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4942 assert_eq!(route.paths[0][0].short_channel_id, 12);
4943 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4944 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4945 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4946 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4948 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4949 assert_eq!(route.paths[0][1].short_channel_id, 13);
4950 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4951 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4952 assert_eq!(route.paths[0][1].node_features.le_flags(), channelmanager::provided_invoice_features(&config).le_flags());
4953 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4958 fn multiple_direct_first_hops() {
4959 // Previously we'd only ever considered one first hop path per counterparty.
4960 // However, as we don't restrict users to one channel per peer, we really need to support
4961 // looking at all first hop paths.
4962 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4963 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4964 // route over multiple channels with the same first hop.
4965 let secp_ctx = Secp256k1::new();
4966 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4967 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4968 let logger = Arc::new(ln_test_utils::TestLogger::new());
4969 let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
4970 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4971 let config = UserConfig::default();
4972 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(channelmanager::provided_invoice_features(&config));
4973 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4974 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4977 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4978 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 200_000),
4979 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 10_000),
4980 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4981 assert_eq!(route.paths.len(), 1);
4982 assert_eq!(route.paths[0].len(), 1);
4984 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4985 assert_eq!(route.paths[0][0].short_channel_id, 3);
4986 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4989 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4990 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
4991 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
4992 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4993 assert_eq!(route.paths.len(), 2);
4994 assert_eq!(route.paths[0].len(), 1);
4995 assert_eq!(route.paths[1].len(), 1);
4997 assert!((route.paths[0][0].short_channel_id == 3 && route.paths[1][0].short_channel_id == 2) ||
4998 (route.paths[0][0].short_channel_id == 2 && route.paths[1][0].short_channel_id == 3));
5000 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5001 assert_eq!(route.paths[0][0].fee_msat, 50_000);
5003 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
5004 assert_eq!(route.paths[1][0].fee_msat, 50_000);
5008 // If we have a bunch of outbound channels to the same node, where most are not
5009 // sufficient to pay the full payment, but one is, we should default to just using the
5010 // one single channel that has sufficient balance, avoiding MPP.
5012 // If we have several options above the 3xpayment value threshold, we should pick the
5013 // smallest of them, avoiding further fragmenting our available outbound balance to
5015 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5016 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5017 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5018 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5019 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(&config), 300_000),
5020 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5021 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5022 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(&config), 50_000),
5023 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(&config), 1_000_000),
5024 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5025 assert_eq!(route.paths.len(), 1);
5026 assert_eq!(route.paths[0].len(), 1);
5028 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5029 assert_eq!(route.paths[0][0].short_channel_id, 6);
5030 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5035 fn prefers_shorter_route_with_higher_fees() {
5036 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5037 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5038 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5040 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5041 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5042 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5043 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5044 let route = get_route(
5045 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5046 Arc::clone(&logger), &scorer, &random_seed_bytes
5048 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5050 assert_eq!(route.get_total_fees(), 100);
5051 assert_eq!(route.get_total_amount(), 100);
5052 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5054 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5055 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5056 let scorer = ln_test_utils::TestScorer::with_penalty(100);
5057 let route = get_route(
5058 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5059 Arc::clone(&logger), &scorer, &random_seed_bytes
5061 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5063 assert_eq!(route.get_total_fees(), 300);
5064 assert_eq!(route.get_total_amount(), 100);
5065 assert_eq!(path, vec![2, 4, 7, 10]);
5068 struct BadChannelScorer {
5069 short_channel_id: u64,
5073 impl Writeable for BadChannelScorer {
5074 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5076 impl Score for BadChannelScorer {
5077 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage) -> u64 {
5078 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5081 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5082 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5083 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5084 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5087 struct BadNodeScorer {
5092 impl Writeable for BadNodeScorer {
5093 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5096 impl Score for BadNodeScorer {
5097 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage) -> u64 {
5098 if *target == self.node_id { u64::max_value() } else { 0 }
5101 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5102 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5103 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5104 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5108 fn avoids_routing_through_bad_channels_and_nodes() {
5109 let (secp_ctx, network, _, _, logger) = build_graph();
5110 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5111 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5112 let network_graph = network.read_only();
5114 // A path to nodes[6] exists when no penalties are applied to any channel.
5115 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5116 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5117 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5118 let route = get_route(
5119 &our_id, &payment_params, &network_graph, None, 100, 42,
5120 Arc::clone(&logger), &scorer, &random_seed_bytes
5122 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5124 assert_eq!(route.get_total_fees(), 100);
5125 assert_eq!(route.get_total_amount(), 100);
5126 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5128 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5129 let scorer = BadChannelScorer { short_channel_id: 6 };
5130 let route = get_route(
5131 &our_id, &payment_params, &network_graph, None, 100, 42,
5132 Arc::clone(&logger), &scorer, &random_seed_bytes
5134 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5136 assert_eq!(route.get_total_fees(), 300);
5137 assert_eq!(route.get_total_amount(), 100);
5138 assert_eq!(path, vec![2, 4, 7, 10]);
5140 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5141 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5143 &our_id, &payment_params, &network_graph, None, 100, 42,
5144 Arc::clone(&logger), &scorer, &random_seed_bytes
5146 Err(LightningError { err, .. } ) => {
5147 assert_eq!(err, "Failed to find a path to the given destination");
5149 Ok(_) => panic!("Expected error"),
5154 fn total_fees_single_path() {
5158 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5159 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5160 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5163 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5164 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5165 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5168 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5169 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5170 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5173 payment_params: None,
5176 assert_eq!(route.get_total_fees(), 250);
5177 assert_eq!(route.get_total_amount(), 225);
5181 fn total_fees_multi_path() {
5185 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5186 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5187 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5190 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5191 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5192 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5196 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5197 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5198 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5201 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5202 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5203 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5206 payment_params: None,
5209 assert_eq!(route.get_total_fees(), 200);
5210 assert_eq!(route.get_total_amount(), 300);
5214 fn total_empty_route_no_panic() {
5215 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5216 // would both panic if the route was completely empty. We test to ensure they return 0
5217 // here, even though its somewhat nonsensical as a route.
5218 let route = Route { paths: Vec::new(), payment_params: None };
5220 assert_eq!(route.get_total_fees(), 0);
5221 assert_eq!(route.get_total_amount(), 0);
5225 fn limits_total_cltv_delta() {
5226 let (secp_ctx, network, _, _, logger) = build_graph();
5227 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5228 let network_graph = network.read_only();
5230 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5232 // Make sure that generally there is at least one route available
5233 let feasible_max_total_cltv_delta = 1008;
5234 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5235 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5236 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5237 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5238 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5239 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5240 assert_ne!(path.len(), 0);
5242 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5243 let fail_max_total_cltv_delta = 23;
5244 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5245 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5246 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5248 Err(LightningError { err, .. } ) => {
5249 assert_eq!(err, "Failed to find a path to the given destination");
5251 Ok(_) => panic!("Expected error"),
5256 fn avoids_recently_failed_paths() {
5257 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5258 // randomly inserting channels into it until we can't find a route anymore.
5259 let (secp_ctx, network, _, _, logger) = build_graph();
5260 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5261 let network_graph = network.read_only();
5263 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5264 let mut payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5265 .with_max_path_count(1);
5266 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5267 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5269 // We should be able to find a route initially, and then after we fail a few random
5270 // channels eventually we won't be able to any longer.
5271 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).is_ok());
5273 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes) {
5274 for chan in route.paths[0].iter() {
5275 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5277 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5278 % route.paths[0].len();
5279 payment_params.previously_failed_channels.push(route.paths[0][victim].short_channel_id);
5285 fn limits_path_length() {
5286 let (secp_ctx, network, _, _, logger) = build_line_graph();
5287 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5288 let network_graph = network.read_only();
5290 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5291 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5292 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5294 // First check we can actually create a long route on this graph.
5295 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5296 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5297 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5298 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5299 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5301 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5302 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5303 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5304 Arc::clone(&logger), &scorer, &random_seed_bytes)
5306 Err(LightningError { err, .. } ) => {
5307 assert_eq!(err, "Failed to find a path to the given destination");
5309 Ok(_) => panic!("Expected error"),
5314 fn adds_and_limits_cltv_offset() {
5315 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5316 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5318 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5320 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5321 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5322 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5323 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5324 assert_eq!(route.paths.len(), 1);
5326 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5328 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5329 let mut route_default = route.clone();
5330 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5331 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5332 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5333 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5334 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5336 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5337 let mut route_limited = route.clone();
5338 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5339 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5340 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5341 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5342 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5346 fn adds_plausible_cltv_offset() {
5347 let (secp_ctx, network, _, _, logger) = build_graph();
5348 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5349 let network_graph = network.read_only();
5350 let network_nodes = network_graph.nodes();
5351 let network_channels = network_graph.channels();
5352 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5353 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5354 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5355 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5357 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5358 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5359 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5361 let mut path_plausibility = vec![];
5363 for p in route.paths {
5364 // 1. Select random observation point
5365 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5366 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5368 prng.process_in_place(&mut random_bytes);
5369 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5370 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5372 // 2. Calculate what CLTV expiry delta we would observe there
5373 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5375 // 3. Starting from the observation point, find candidate paths
5376 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5377 candidates.push_back((observation_point, vec![]));
5379 let mut found_plausible_candidate = false;
5381 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5382 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5383 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5384 found_plausible_candidate = true;
5385 break 'candidate_loop;
5389 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5390 for channel_id in &cur_node.channels {
5391 if let Some(channel_info) = network_channels.get(&channel_id) {
5392 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5393 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
5394 if cur_path_cltv_deltas.iter().sum::<u32>()
5395 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5396 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5397 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5398 candidates.push_back((*next_id, new_path_cltv_deltas));
5406 path_plausibility.push(found_plausible_candidate);
5408 assert!(path_plausibility.iter().all(|x| *x));
5412 fn builds_correct_path_from_hops() {
5413 let (secp_ctx, network, _, _, logger) = build_graph();
5414 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5415 let network_graph = network.read_only();
5417 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5418 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5420 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5421 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5422 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5423 &network_graph, 100, 0, Arc::clone(&logger), &random_seed_bytes).unwrap();
5424 let route_hop_pubkeys = route.paths[0].iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5425 assert_eq!(hops.len(), route.paths[0].len());
5426 for (idx, hop_pubkey) in hops.iter().enumerate() {
5427 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5432 fn avoids_saturating_channels() {
5433 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5434 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5436 let scorer = ProbabilisticScorer::new(Default::default(), &*network_graph, Arc::clone(&logger));
5438 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5439 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5440 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5441 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5442 short_channel_id: 4,
5445 cltv_expiry_delta: (4 << 4) | 1,
5446 htlc_minimum_msat: 0,
5447 htlc_maximum_msat: 250_000_000,
5449 fee_proportional_millionths: 0,
5450 excess_data: Vec::new()
5452 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5453 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5454 short_channel_id: 13,
5457 cltv_expiry_delta: (13 << 4) | 1,
5458 htlc_minimum_msat: 0,
5459 htlc_maximum_msat: 250_000_000,
5461 fee_proportional_millionths: 0,
5462 excess_data: Vec::new()
5465 let config = UserConfig::default();
5466 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features(&config));
5467 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5468 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5469 // 100,000 sats is less than the available liquidity on each channel, set above.
5470 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5471 assert_eq!(route.paths.len(), 2);
5472 assert!((route.paths[0][1].short_channel_id == 4 && route.paths[1][1].short_channel_id == 13) ||
5473 (route.paths[1][1].short_channel_id == 4 && route.paths[0][1].short_channel_id == 13));
5476 #[cfg(not(feature = "no-std"))]
5477 pub(super) fn random_init_seed() -> u64 {
5478 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5479 use core::hash::{BuildHasher, Hasher};
5480 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5481 println!("Using seed of {}", seed);
5484 #[cfg(not(feature = "no-std"))]
5485 use crate::util::ser::ReadableArgs;
5488 #[cfg(not(feature = "no-std"))]
5489 fn generate_routes() {
5490 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5492 let mut d = match super::bench_utils::get_route_file() {
5499 let logger = ln_test_utils::TestLogger::new();
5500 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5501 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5502 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5504 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5505 let mut seed = random_init_seed() as usize;
5506 let nodes = graph.read_only().nodes().clone();
5507 'load_endpoints: for _ in 0..10 {
5509 seed = seed.overflowing_mul(0xdeadbeef).0;
5510 let src = &PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5511 seed = seed.overflowing_mul(0xdeadbeef).0;
5512 let dst = PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5513 let payment_params = PaymentParameters::from_node_id(dst);
5514 let amt = seed as u64 % 200_000_000;
5515 let params = ProbabilisticScoringParameters::default();
5516 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5517 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5518 continue 'load_endpoints;
5525 #[cfg(not(feature = "no-std"))]
5526 fn generate_routes_mpp() {
5527 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5529 let mut d = match super::bench_utils::get_route_file() {
5536 let logger = ln_test_utils::TestLogger::new();
5537 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5538 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5539 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5540 let config = UserConfig::default();
5542 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5543 let mut seed = random_init_seed() as usize;
5544 let nodes = graph.read_only().nodes().clone();
5545 'load_endpoints: for _ in 0..10 {
5547 seed = seed.overflowing_mul(0xdeadbeef).0;
5548 let src = &PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5549 seed = seed.overflowing_mul(0xdeadbeef).0;
5550 let dst = PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5551 let payment_params = PaymentParameters::from_node_id(dst).with_features(channelmanager::provided_invoice_features(&config));
5552 let amt = seed as u64 % 200_000_000;
5553 let params = ProbabilisticScoringParameters::default();
5554 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5555 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5556 continue 'load_endpoints;
5563 fn honors_manual_penalties() {
5564 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5565 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5567 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5568 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5570 let scorer_params = ProbabilisticScoringParameters::default();
5571 let mut scorer = ProbabilisticScorer::new(scorer_params, Arc::clone(&network_graph), Arc::clone(&logger));
5573 // First check set manual penalties are returned by the scorer.
5574 let usage = ChannelUsage {
5576 inflight_htlc_msat: 0,
5577 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
5579 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5580 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5581 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage), 456);
5583 // Then check we can get a normal route
5584 let payment_params = PaymentParameters::from_node_id(nodes[10]);
5585 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5586 assert!(route.is_ok());
5588 // Then check that we can't get a route if we ban an intermediate node.
5589 scorer.add_banned(&NodeId::from_pubkey(&nodes[3]));
5590 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5591 assert!(route.is_err());
5593 // Finally make sure we can route again, when we remove the ban.
5594 scorer.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5595 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5596 assert!(route.is_ok());
5600 #[cfg(all(test, not(feature = "no-std")))]
5601 pub(crate) mod bench_utils {
5603 /// Tries to open a network graph file, or panics with a URL to fetch it.
5604 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5605 let res = File::open("net_graph-2023-01-18.bin") // By default we're run in RL/lightning
5606 .or_else(|_| File::open("lightning/net_graph-2023-01-18.bin")) // We may be run manually in RL/
5607 .or_else(|_| { // Fall back to guessing based on the binary location
5608 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5609 let mut path = std::env::current_exe().unwrap();
5610 path.pop(); // lightning-...
5612 path.pop(); // debug
5613 path.pop(); // target
5614 path.push("lightning");
5615 path.push("net_graph-2023-01-18.bin");
5616 eprintln!("{}", path.to_str().unwrap());
5619 .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");
5620 #[cfg(require_route_graph_test)]
5621 return Ok(res.unwrap());
5622 #[cfg(not(require_route_graph_test))]
5627 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5630 use bitcoin::hashes::Hash;
5631 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5632 use crate::chain::transaction::OutPoint;
5633 use crate::chain::keysinterface::{EntropySource, KeysManager};
5634 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
5635 use crate::ln::features::InvoiceFeatures;
5636 use crate::routing::gossip::NetworkGraph;
5637 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
5638 use crate::util::config::UserConfig;
5639 use crate::util::logger::{Logger, Record};
5640 use crate::util::ser::ReadableArgs;
5644 struct DummyLogger {}
5645 impl Logger for DummyLogger {
5646 fn log(&self, _record: &Record) {}
5649 fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
5650 let mut d = bench_utils::get_route_file().unwrap();
5651 NetworkGraph::read(&mut d, logger).unwrap()
5654 fn payer_pubkey() -> PublicKey {
5655 let secp_ctx = Secp256k1::new();
5656 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5660 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5662 channel_id: [0; 32],
5663 counterparty: ChannelCounterparty {
5664 features: channelmanager::provided_init_features(&UserConfig::default()),
5666 unspendable_punishment_reserve: 0,
5667 forwarding_info: None,
5668 outbound_htlc_minimum_msat: None,
5669 outbound_htlc_maximum_msat: None,
5671 funding_txo: Some(OutPoint {
5672 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5675 short_channel_id: Some(1),
5676 inbound_scid_alias: None,
5677 outbound_scid_alias: None,
5678 channel_value_satoshis: 10_000_000,
5680 balance_msat: 10_000_000,
5681 outbound_capacity_msat: 10_000_000,
5682 next_outbound_htlc_limit_msat: 10_000_000,
5683 inbound_capacity_msat: 0,
5684 unspendable_punishment_reserve: None,
5685 confirmations_required: None,
5686 confirmations: None,
5687 force_close_spend_delay: None,
5689 is_channel_ready: true,
5692 inbound_htlc_minimum_msat: None,
5693 inbound_htlc_maximum_msat: None,
5699 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5700 let logger = DummyLogger {};
5701 let network_graph = read_network_graph(&logger);
5702 let scorer = FixedPenaltyScorer::with_penalty(0);
5703 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5707 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5708 let logger = DummyLogger {};
5709 let network_graph = read_network_graph(&logger);
5710 let scorer = FixedPenaltyScorer::with_penalty(0);
5711 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features(&UserConfig::default()));
5715 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5716 let logger = DummyLogger {};
5717 let network_graph = read_network_graph(&logger);
5718 let params = ProbabilisticScoringParameters::default();
5719 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5720 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5724 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5725 let logger = DummyLogger {};
5726 let network_graph = read_network_graph(&logger);
5727 let params = ProbabilisticScoringParameters::default();
5728 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5729 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features(&UserConfig::default()));
5732 fn generate_routes<S: Score>(
5733 bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
5734 features: InvoiceFeatures
5736 let nodes = graph.read_only().nodes().clone();
5737 let payer = payer_pubkey();
5738 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5739 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5741 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5742 let mut routes = Vec::new();
5743 let mut route_endpoints = Vec::new();
5744 let mut seed: usize = 0xdeadbeef;
5745 'load_endpoints: for _ in 0..150 {
5748 let src = PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5750 let dst = PublicKey::from_slice(nodes.unordered_keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5751 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5752 let first_hop = first_hop(src);
5753 let amt = seed as u64 % 1_000_000;
5754 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5756 route_endpoints.push((first_hop, params, amt));
5757 continue 'load_endpoints;
5762 // ...and seed the scorer with success and failure data...
5763 for route in routes {
5764 let amount = route.get_total_amount();
5765 if amount < 250_000 {
5766 for path in route.paths {
5767 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5769 } else if amount > 750_000 {
5770 for path in route.paths {
5771 let short_channel_id = path[path.len() / 2].short_channel_id;
5772 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5777 // Because we've changed channel scores, its possible we'll take different routes to the
5778 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5779 // requires a too-high CLTV delta.
5780 route_endpoints.retain(|(first_hop, params, amt)| {
5781 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5783 route_endpoints.truncate(100);
5784 assert_eq!(route_endpoints.len(), 100);
5786 // ...then benchmark finding paths between the nodes we learned.
5789 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5790 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());