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;
17 use crate::ln::channelmanager::ChannelDetails;
18 use crate::ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
19 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
20 use crate::routing::gossip::{DirectedChannelInfoWithUpdate, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
21 use crate::routing::scoring::{ChannelUsage, Score};
22 use crate::util::ser::{Writeable, Readable, Writer};
23 use crate::util::logger::{Level, Logger};
24 use crate::util::chacha20::ChaCha20;
27 use crate::prelude::*;
28 use alloc::collections::BinaryHeap;
33 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
35 /// The node_id of the node at this hop.
36 pub pubkey: PublicKey,
37 /// The node_announcement features of the node at this hop. For the last hop, these may be
38 /// amended to match the features present in the invoice this node generated.
39 pub node_features: NodeFeatures,
40 /// The channel that should be used from the previous hop to reach this node.
41 pub short_channel_id: u64,
42 /// The channel_announcement features of the channel that should be used from the previous hop
43 /// to reach this node.
44 pub channel_features: ChannelFeatures,
45 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
46 /// For the last hop, this should be the full value of the payment (might be more than
47 /// requested if we had to match htlc_minimum_msat).
49 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
50 /// expected at the destination, in excess of the current block height.
51 pub cltv_expiry_delta: u32,
54 impl_writeable_tlv_based!(RouteHop, {
55 (0, pubkey, required),
56 (2, node_features, required),
57 (4, short_channel_id, required),
58 (6, channel_features, required),
59 (8, fee_msat, required),
60 (10, cltv_expiry_delta, required),
63 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
64 /// it can take multiple paths. Each path is composed of one or more hops through the network.
65 #[derive(Clone, Hash, PartialEq, Eq)]
67 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
68 /// last RouteHop in each path must be the same. Each entry represents a list of hops, NOT
69 /// INCLUDING our own, where the last hop is the destination. Thus, this must always be at
70 /// least length one. While the maximum length of any given path is variable, keeping the length
71 /// of any path less or equal to 19 should currently ensure it is viable.
72 pub paths: Vec<Vec<RouteHop>>,
73 /// The `payment_params` parameter passed to [`find_route`].
74 /// This is used by `ChannelManager` to track information which may be required for retries,
75 /// provided back to you via [`Event::PaymentPathFailed`].
77 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
78 pub payment_params: Option<PaymentParameters>,
81 pub(crate) trait RoutePath {
82 /// Gets the fees for a given path, excluding any excess paid to the recipient.
83 fn get_path_fees(&self) -> u64;
85 impl RoutePath for Vec<RouteHop> {
86 fn get_path_fees(&self) -> u64 {
87 // Do not count last hop of each path since that's the full value of the payment
88 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
89 .iter().map(|hop| &hop.fee_msat)
95 /// Returns the total amount of fees paid on this [`Route`].
97 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
98 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
99 pub fn get_total_fees(&self) -> u64 {
100 self.paths.iter().map(|path| path.get_path_fees()).sum()
103 /// Returns the total amount paid on this [`Route`], excluding the fees.
104 pub fn get_total_amount(&self) -> u64 {
105 return self.paths.iter()
106 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
111 const SERIALIZATION_VERSION: u8 = 1;
112 const MIN_SERIALIZATION_VERSION: u8 = 1;
114 impl Writeable for Route {
115 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
116 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
117 (self.paths.len() as u64).write(writer)?;
118 for hops in self.paths.iter() {
119 (hops.len() as u8).write(writer)?;
120 for hop in hops.iter() {
124 write_tlv_fields!(writer, {
125 (1, self.payment_params, option),
131 impl Readable for Route {
132 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
133 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
134 let path_count: u64 = Readable::read(reader)?;
135 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
136 for _ in 0..path_count {
137 let hop_count: u8 = Readable::read(reader)?;
138 let mut hops = Vec::with_capacity(hop_count as usize);
139 for _ in 0..hop_count {
140 hops.push(Readable::read(reader)?);
144 let mut payment_params = None;
145 read_tlv_fields!(reader, {
146 (1, payment_params, option),
148 Ok(Route { paths, payment_params })
152 /// Parameters needed to find a [`Route`].
154 /// Passed to [`find_route`] and [`build_route_from_hops`], but also provided in
155 /// [`Event::PaymentPathFailed`] for retrying a failed payment path.
157 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
158 #[derive(Clone, Debug)]
159 pub struct RouteParameters {
160 /// The parameters of the failed payment path.
161 pub payment_params: PaymentParameters,
163 /// The amount in msats sent on the failed payment path.
164 pub final_value_msat: u64,
166 /// The CLTV on the final hop of the failed payment path.
167 pub final_cltv_expiry_delta: u32,
170 impl_writeable_tlv_based!(RouteParameters, {
171 (0, payment_params, required),
172 (2, final_value_msat, required),
173 (4, final_cltv_expiry_delta, required),
176 /// Maximum total CTLV difference we allow for a full payment path.
177 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
179 /// Maximum number of paths we allow an (MPP) payment to have.
180 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
181 // limits, but for now more than 10 paths likely carries too much one-path failure.
182 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
184 // The median hop CLTV expiry delta currently seen in the network.
185 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
187 // During routing, we only consider paths shorter than our maximum length estimate.
188 // In the legacy onion format, the maximum number of hops used to be a fixed value of 20.
189 // However, in the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
190 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
191 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
193 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
194 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
195 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
196 // (payment_secret and total_msat) = 93 bytes for the final hop.
197 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
198 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
199 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
201 /// The recipient of a payment.
202 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
203 pub struct PaymentParameters {
204 /// The node id of the payee.
205 pub payee_pubkey: PublicKey,
207 /// Features supported by the payee.
209 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
210 /// does not contain any features.
212 /// [`for_keysend`]: Self::for_keysend
213 pub features: Option<InvoiceFeatures>,
215 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
216 pub route_hints: Vec<RouteHint>,
218 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
219 pub expiry_time: Option<u64>,
221 /// The maximum total CLTV delta we accept for the route.
222 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
223 pub max_total_cltv_expiry_delta: u32,
225 /// The maximum number of paths that may be used by (MPP) payments.
226 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
227 pub max_path_count: u8,
229 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
230 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
231 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
232 /// increasing failure probability for those paths.
234 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
235 /// restriction have been found. While paths which meet this criteria will be searched for, it
236 /// is ultimately up to the scorer to select them over other paths.
238 /// A value of 0 will allow payments up to and including a channel's total announced usable
239 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
242 pub max_channel_saturation_power_of_half: u8,
244 /// A list of SCIDs which this payment was previously attempted over and which caused the
245 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
247 pub previously_failed_channels: Vec<u64>,
250 impl_writeable_tlv_based!(PaymentParameters, {
251 (0, payee_pubkey, required),
252 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
253 (2, features, option),
254 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
255 (4, route_hints, vec_type),
256 (5, max_channel_saturation_power_of_half, (default_value, 2)),
257 (6, expiry_time, option),
258 (7, previously_failed_channels, vec_type),
261 impl PaymentParameters {
262 /// Creates a payee with the node id of the given `pubkey`.
263 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
269 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
270 max_path_count: DEFAULT_MAX_PATH_COUNT,
271 max_channel_saturation_power_of_half: 2,
272 previously_failed_channels: Vec::new(),
276 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
277 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
278 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
281 /// Includes the payee's features.
283 /// (C-not exported) since bindings don't support move semantics
284 pub fn with_features(self, features: InvoiceFeatures) -> Self {
285 Self { features: Some(features), ..self }
288 /// Includes hints for routing to the payee.
290 /// (C-not exported) since bindings don't support move semantics
291 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
292 Self { route_hints, ..self }
295 /// Includes a payment expiration in seconds relative to the UNIX epoch.
297 /// (C-not exported) since bindings don't support move semantics
298 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
299 Self { expiry_time: Some(expiry_time), ..self }
302 /// Includes a limit for the total CLTV expiry delta which is considered during routing
304 /// (C-not exported) since bindings don't support move semantics
305 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
306 Self { max_total_cltv_expiry_delta, ..self }
309 /// Includes a limit for the maximum number of payment paths that may be used.
311 /// (C-not exported) since bindings don't support move semantics
312 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
313 Self { max_path_count, ..self }
316 /// Includes a limit for the maximum number of payment paths that may be used.
318 /// (C-not exported) since bindings don't support move semantics
319 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
320 Self { max_channel_saturation_power_of_half, ..self }
324 /// A list of hops along a payment path terminating with a channel to the recipient.
325 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
326 pub struct RouteHint(pub Vec<RouteHintHop>);
328 impl Writeable for RouteHint {
329 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
330 (self.0.len() as u64).write(writer)?;
331 for hop in self.0.iter() {
338 impl Readable for RouteHint {
339 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
340 let hop_count: u64 = Readable::read(reader)?;
341 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
342 for _ in 0..hop_count {
343 hops.push(Readable::read(reader)?);
349 /// A channel descriptor for a hop along a payment path.
350 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
351 pub struct RouteHintHop {
352 /// The node_id of the non-target end of the route
353 pub src_node_id: PublicKey,
354 /// The short_channel_id of this channel
355 pub short_channel_id: u64,
356 /// The fees which must be paid to use this channel
357 pub fees: RoutingFees,
358 /// The difference in CLTV values between this node and the next node.
359 pub cltv_expiry_delta: u16,
360 /// The minimum value, in msat, which must be relayed to the next hop.
361 pub htlc_minimum_msat: Option<u64>,
362 /// The maximum value in msat available for routing with a single HTLC.
363 pub htlc_maximum_msat: Option<u64>,
366 impl_writeable_tlv_based!(RouteHintHop, {
367 (0, src_node_id, required),
368 (1, htlc_minimum_msat, option),
369 (2, short_channel_id, required),
370 (3, htlc_maximum_msat, option),
372 (6, cltv_expiry_delta, required),
375 #[derive(Eq, PartialEq)]
376 struct RouteGraphNode {
378 lowest_fee_to_peer_through_node: u64,
379 lowest_fee_to_node: u64,
380 total_cltv_delta: u32,
381 // The maximum value a yet-to-be-constructed payment path might flow through this node.
382 // This value is upper-bounded by us by:
383 // - how much is needed for a path being constructed
384 // - how much value can channels following this node (up to the destination) can contribute,
385 // considering their capacity and fees
386 value_contribution_msat: u64,
387 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
388 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
389 path_htlc_minimum_msat: u64,
390 /// All penalties incurred from this hop on the way to the destination, as calculated using
392 path_penalty_msat: u64,
393 /// The number of hops walked up to this node.
394 path_length_to_node: u8,
397 impl cmp::Ord for RouteGraphNode {
398 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
399 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
400 .saturating_add(other.path_penalty_msat);
401 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
402 .saturating_add(self.path_penalty_msat);
403 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
407 impl cmp::PartialOrd for RouteGraphNode {
408 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
409 Some(self.cmp(other))
413 /// A wrapper around the various hop representations.
415 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
416 #[derive(Clone, Debug)]
417 enum CandidateRouteHop<'a> {
418 /// A hop from the payer, where the outbound liquidity is known.
420 details: &'a ChannelDetails,
422 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
424 info: DirectedChannelInfoWithUpdate<'a>,
425 short_channel_id: u64,
427 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
429 hint: &'a RouteHintHop,
433 impl<'a> CandidateRouteHop<'a> {
434 fn short_channel_id(&self) -> u64 {
436 CandidateRouteHop::FirstHop { details } => details.get_outbound_payment_scid().unwrap(),
437 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
438 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
442 // NOTE: This may alloc memory so avoid calling it in a hot code path.
443 fn features(&self) -> ChannelFeatures {
445 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
446 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
447 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
451 fn cltv_expiry_delta(&self) -> u32 {
453 CandidateRouteHop::FirstHop { .. } => 0,
454 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
455 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
459 fn htlc_minimum_msat(&self) -> u64 {
461 CandidateRouteHop::FirstHop { .. } => 0,
462 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
463 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
467 fn fees(&self) -> RoutingFees {
469 CandidateRouteHop::FirstHop { .. } => RoutingFees {
470 base_msat: 0, proportional_millionths: 0,
472 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
473 CandidateRouteHop::PrivateHop { hint } => hint.fees,
477 fn effective_capacity(&self) -> EffectiveCapacity {
479 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
480 liquidity_msat: details.next_outbound_htlc_limit_msat,
482 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
483 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
489 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
490 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
492 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
493 EffectiveCapacity::Infinite => u64::max_value(),
494 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
495 EffectiveCapacity::MaximumHTLC { amount_msat } =>
496 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
497 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: None } =>
498 capacity_msat.checked_shr(saturation_shift).unwrap_or(0),
499 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: Some(htlc_max) } =>
500 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_max),
504 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
505 -> bool where I1::Item: PartialEq<I2::Item> {
507 let a = iter_a.next();
508 let b = iter_b.next();
509 if a.is_none() && b.is_none() { return true; }
510 if a.is_none() || b.is_none() { return false; }
511 if a.unwrap().ne(&b.unwrap()) { return false; }
515 /// It's useful to keep track of the hops associated with the fees required to use them,
516 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
517 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
518 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
520 struct PathBuildingHop<'a> {
521 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
522 // is a larger refactor and will require careful performance analysis.
524 candidate: CandidateRouteHop<'a>,
527 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
528 src_lowest_inbound_fees: RoutingFees,
529 /// All the fees paid *after* this channel on the way to the destination
530 next_hops_fee_msat: u64,
531 /// Fee paid for the use of the current channel (see candidate.fees()).
532 /// The value will be actually deducted from the counterparty balance on the previous link.
533 hop_use_fee_msat: u64,
534 /// Used to compare channels when choosing the for routing.
535 /// Includes paying for the use of a hop and the following hops, as well as
536 /// an estimated cost of reaching this hop.
537 /// Might get stale when fees are recomputed. Primarily for internal use.
539 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
540 /// walk and may be invalid thereafter.
541 path_htlc_minimum_msat: u64,
542 /// All penalties incurred from this channel on the way to the destination, as calculated using
544 path_penalty_msat: u64,
545 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
546 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
547 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
548 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
549 /// avoid processing them again.
551 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
552 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
553 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
554 // value_contribution_msat, which requires tracking it here. See comments below where it is
555 // used for more info.
556 value_contribution_msat: u64,
559 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
560 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
561 let mut debug_struct = f.debug_struct("PathBuildingHop");
563 .field("node_id", &self.node_id)
564 .field("short_channel_id", &self.candidate.short_channel_id())
565 .field("total_fee_msat", &self.total_fee_msat)
566 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
567 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
568 .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)))
569 .field("path_penalty_msat", &self.path_penalty_msat)
570 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
571 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
572 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
573 let debug_struct = debug_struct
574 .field("value_contribution_msat", &self.value_contribution_msat);
575 debug_struct.finish()
579 // Instantiated with a list of hops with correct data in them collected during path finding,
580 // an instance of this struct should be further modified only via given methods.
582 struct PaymentPath<'a> {
583 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
586 impl<'a> PaymentPath<'a> {
587 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
588 fn get_value_msat(&self) -> u64 {
589 self.hops.last().unwrap().0.fee_msat
592 fn get_path_penalty_msat(&self) -> u64 {
593 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
596 fn get_total_fee_paid_msat(&self) -> u64 {
597 if self.hops.len() < 1 {
601 // Can't use next_hops_fee_msat because it gets outdated.
602 for (i, (hop, _)) in self.hops.iter().enumerate() {
603 if i != self.hops.len() - 1 {
604 result += hop.fee_msat;
610 fn get_cost_msat(&self) -> u64 {
611 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
614 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
615 // to change fees may result in an inconsistency.
617 // Sometimes we call this function right after constructing a path which is inconsistent in
618 // that it the value being transferred has decreased while we were doing path finding, leading
619 // to the fees being paid not lining up with the actual limits.
621 // Note that this function is not aware of the available_liquidity limit, and thus does not
622 // support increasing the value being transferred beyond what was selected during the initial
624 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
625 let mut total_fee_paid_msat = 0 as u64;
626 for i in (0..self.hops.len()).rev() {
627 let last_hop = i == self.hops.len() - 1;
629 // For non-last-hop, this value will represent the fees paid on the current hop. It
630 // will consist of the fees for the use of the next hop, and extra fees to match
631 // htlc_minimum_msat of the current channel. Last hop is handled separately.
632 let mut cur_hop_fees_msat = 0;
634 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
637 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
638 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
639 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
640 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
641 // set it too high just to maliciously take more fees by exploiting this
642 // match htlc_minimum_msat logic.
643 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
644 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
645 // Note that there is a risk that *previous hops* (those closer to us, as we go
646 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
648 // This might make us end up with a broken route, although this should be super-rare
649 // in practice, both because of how healthy channels look like, and how we pick
650 // channels in add_entry.
651 // Also, this can't be exploited more heavily than *announce a free path and fail
653 cur_hop_transferred_amount_msat += extra_fees_msat;
654 total_fee_paid_msat += extra_fees_msat;
655 cur_hop_fees_msat += extra_fees_msat;
659 // Final hop is a special case: it usually has just value_msat (by design), but also
660 // it still could overpay for the htlc_minimum_msat.
661 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
663 // Propagate updated fees for the use of the channels to one hop back, where they
664 // will be actually paid (fee_msat). The last hop is handled above separately.
665 cur_hop.fee_msat = cur_hop_fees_msat;
668 // Fee for the use of the current hop which will be deducted on the previous hop.
669 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
670 // this channel is free for us.
672 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
673 cur_hop.hop_use_fee_msat = new_fee;
674 total_fee_paid_msat += new_fee;
676 // It should not be possible because this function is called only to reduce the
677 // value. In that case, compute_fee was already called with the same fees for
678 // larger amount and there was no overflow.
686 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
687 let proportional_fee_millions =
688 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
689 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
690 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
694 // This function may be (indirectly) called without any verification,
695 // with channel_fees provided by a caller. We should handle it gracefully.
700 /// The default `features` we assume for a node in a route, when no `features` are known about that
703 /// Default features are:
704 /// * variable_length_onion_optional
705 fn default_node_features() -> NodeFeatures {
706 let mut features = NodeFeatures::empty();
707 features.set_variable_length_onion_optional();
711 /// Finds a route from us (payer) to the given target node (payee).
713 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
714 /// Without this, MPP will only be used if the payee's features are available in the network graph.
716 /// Private routing paths between a public node and the target may be included in `params.payee`.
718 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
719 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
720 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
722 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
723 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
724 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
728 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
729 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
734 /// Panics if first_hops contains channels without short_channel_ids;
735 /// [`ChannelManager::list_usable_channels`] will never include such channels.
737 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
738 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
739 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
740 pub fn find_route<L: Deref, GL: Deref, S: Score>(
741 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
742 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
743 scorer: &S, random_seed_bytes: &[u8; 32]
744 ) -> Result<Route, LightningError>
745 where L::Target: Logger, GL::Target: Logger {
746 let graph_lock = network_graph.read_only();
747 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
748 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, scorer,
750 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
754 pub(crate) fn get_route<L: Deref, S: Score>(
755 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
756 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
757 logger: L, scorer: &S, _random_seed_bytes: &[u8; 32]
758 ) -> Result<Route, LightningError>
759 where L::Target: Logger {
760 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
761 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
763 if payee_node_id == our_node_id {
764 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
767 if final_value_msat > MAX_VALUE_MSAT {
768 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
771 if final_value_msat == 0 {
772 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
775 for route in payment_params.route_hints.iter() {
776 for hop in &route.0 {
777 if hop.src_node_id == payment_params.payee_pubkey {
778 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
782 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
783 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});
786 // The general routing idea is the following:
787 // 1. Fill first/last hops communicated by the caller.
788 // 2. Attempt to construct a path from payer to payee for transferring
789 // any ~sufficient (described later) value.
790 // If succeed, remember which channels were used and how much liquidity they have available,
791 // so that future paths don't rely on the same liquidity.
792 // 3. Proceed to the next step if:
793 // - we hit the recommended target value;
794 // - OR if we could not construct a new path. Any next attempt will fail too.
795 // Otherwise, repeat step 2.
796 // 4. See if we managed to collect paths which aggregately are able to transfer target value
797 // (not recommended value).
798 // 5. If yes, proceed. If not, fail routing.
799 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
800 // transferred up to the transfer target value.
801 // 7. Reduce the value of the last path until we are sending only the target value.
802 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
803 // them so that we're not sending two HTLCs along the same path.
805 // As for the actual search algorithm,
806 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
807 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
809 // We are not a faithful Dijkstra's implementation because we can change values which impact
810 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
811 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
812 // the value we are currently attempting to send over a path, we simply reduce the value being
813 // sent along the path for any hops after that channel. This may imply that later fees (which
814 // we've already tabulated) are lower because a smaller value is passing through the channels
815 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
816 // channels which were selected earlier (and which may still be used for other paths without a
817 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
820 // One potentially problematic case for this algorithm would be if there are many
821 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
822 // graph walking), we may never find a path which is not liquidity-limited and has lower
823 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
824 // Because we only consider paths with at least 5% of the total value being sent, the damage
825 // from such a case should be limited, however this could be further reduced in the future by
826 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
827 // limits for the purposes of fee calculation.
829 // Alternatively, we could store more detailed path information in the heap (targets, below)
830 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
831 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
832 // and practically (as we would need to store dynamically-allocated path information in heap
833 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
834 // results of such an algorithm would likely be biased towards lower-value paths.
836 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
837 // outside of our current search value, running a path search more times to gather candidate
838 // paths at different values. While this may be acceptable, further path searches may increase
839 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
840 // graph for candidate paths, calculating the maximum value which can realistically be sent at
841 // the same time, remaining generic across different payment values.
843 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
844 // to use as the A* heuristic beyond just the cost to get one node further than the current
847 let network_channels = network_graph.channels();
848 let network_nodes = network_graph.nodes();
850 if payment_params.max_path_count == 0 {
851 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
854 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
855 // it. If the payee supports it they're supposed to include it in the invoice, so that should
857 let allow_mpp = if payment_params.max_path_count == 1 {
859 } else if let Some(features) = &payment_params.features {
860 features.supports_basic_mpp()
861 } else if let Some(node) = network_nodes.get(&payee_node_id) {
862 if let Some(node_info) = node.announcement_info.as_ref() {
863 node_info.features.supports_basic_mpp()
867 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
868 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
869 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
872 // Prepare the data we'll use for payee-to-payer search by
873 // inserting first hops suggested by the caller as targets.
874 // Our search will then attempt to reach them while traversing from the payee node.
875 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
876 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
877 if let Some(hops) = first_hops {
879 if chan.get_outbound_payment_scid().is_none() {
880 panic!("first_hops should be filled in with usable channels, not pending ones");
882 if chan.counterparty.node_id == *our_node_pubkey {
883 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
886 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
887 .or_insert(Vec::new())
890 if first_hop_targets.is_empty() {
891 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
895 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
896 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
897 // adding duplicate entries when we find a better path to a given node.
898 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
900 // Map from node_id to information about the best current path to that node, including feerate
902 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
904 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
905 // indicating that we may wish to try again with a higher value, potentially paying to meet an
906 // htlc_minimum with extra fees while still finding a cheaper path.
907 let mut hit_minimum_limit;
909 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
910 // We start with a path_value of the exact amount we want, and if that generates a route we may
911 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
912 // amount we want in total across paths, selecting the best subset at the end.
913 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
914 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
915 let mut path_value_msat = final_value_msat;
917 // Routing Fragmentation Mitigation heuristic:
919 // Routing fragmentation across many payment paths increases the overall routing
920 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
921 // Taking too many smaller paths also increases the chance of payment failure.
922 // Thus to avoid this effect, we require from our collected links to provide
923 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
924 // This requirement is currently set to be 1/max_path_count of the payment
925 // value to ensure we only ever return routes that do not violate this limit.
926 let minimal_value_contribution_msat: u64 = if allow_mpp {
927 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
932 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
933 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
934 // drop the requirement by setting this to 0.
935 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
937 // Keep track of how much liquidity has been used in selected channels. Used to determine
938 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
939 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
940 // liquidity used in one direction will not offset any used in the opposite direction.
941 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
942 HashMap::with_capacity(network_nodes.len());
944 // Keeping track of how much value we already collected across other paths. Helps to decide
945 // when we want to stop looking for new paths.
946 let mut already_collected_value_msat = 0;
948 for (_, channels) in first_hop_targets.iter_mut() {
949 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
952 // First, if channels are below `recommended_value_msat`, sort them in descending order,
953 // preferring larger channels to avoid splitting the payment into more MPP parts than is
956 // Second, because simply always sorting in descending order would always use our largest
957 // available outbound capacity, needlessly fragmenting our available channel capacities,
958 // sort channels above `recommended_value_msat` in ascending order, preferring channels
959 // which have enough, but not too much, capacity for the payment.
960 channels.sort_unstable_by(|chan_a, chan_b| {
961 if chan_b.next_outbound_htlc_limit_msat < recommended_value_msat || chan_a.next_outbound_htlc_limit_msat < recommended_value_msat {
962 // Sort in descending order
963 chan_b.next_outbound_htlc_limit_msat.cmp(&chan_a.next_outbound_htlc_limit_msat)
965 // Sort in ascending order
966 chan_a.next_outbound_htlc_limit_msat.cmp(&chan_b.next_outbound_htlc_limit_msat)
971 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
973 macro_rules! add_entry {
974 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
975 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
976 // since that value has to be transferred over this channel.
977 // Returns whether this channel caused an update to `targets`.
978 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
979 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
980 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
981 // We "return" whether we updated the path at the end, via this:
982 let mut did_add_update_path_to_src_node = false;
983 // Channels to self should not be used. This is more of belt-and-suspenders, because in
984 // practice these cases should be caught earlier:
985 // - for regular channels at channel announcement (TODO)
986 // - for first and last hops early in get_route
987 if $src_node_id != $dest_node_id {
988 let short_channel_id = $candidate.short_channel_id();
989 let effective_capacity = $candidate.effective_capacity();
990 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
992 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
993 // It may be misleading because we might later choose to reduce the value transferred
994 // over these channels, and the channel which was insufficient might become sufficient.
995 // Worst case: we drop a good channel here because it can't cover the high following
996 // fees caused by one expensive channel, but then this channel could have been used
997 // if the amount being transferred over this path is lower.
998 // We do this for now, but this is a subject for removal.
999 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1000 let used_liquidity_msat = used_channel_liquidities
1001 .get(&(short_channel_id, $src_node_id < $dest_node_id))
1002 .map_or(0, |used_liquidity_msat| {
1003 available_value_contribution_msat = available_value_contribution_msat
1004 .saturating_sub(*used_liquidity_msat);
1005 *used_liquidity_msat
1008 // Verify the liquidity offered by this channel complies to the minimal contribution.
1009 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1010 // Do not consider candidate hops that would exceed the maximum path length.
1011 let path_length_to_node = $next_hops_path_length + 1;
1012 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1014 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1015 // In order to already account for some of the privacy enhancing random CLTV
1016 // expiry delta offset we add on top later, we subtract a rough estimate
1017 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1018 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1019 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1020 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1021 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1022 .saturating_add($candidate.cltv_expiry_delta());
1023 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1025 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1026 // Includes paying fees for the use of the following channels.
1027 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1028 Some(result) => result,
1029 // Can't overflow due to how the values were computed right above.
1030 None => unreachable!(),
1032 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1033 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1034 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1036 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1037 let may_overpay_to_meet_path_minimum_msat =
1038 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1039 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1040 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1041 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1043 let payment_failed_on_this_channel =
1044 payment_params.previously_failed_channels.contains(&short_channel_id);
1046 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1047 // bother considering this channel. If retrying with recommended_value_msat may
1048 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1049 // around again with a higher amount.
1050 if !contributes_sufficient_value || exceeds_max_path_length ||
1051 exceeds_cltv_delta_limit || payment_failed_on_this_channel {
1052 // Path isn't useful, ignore it and move on.
1053 } else if may_overpay_to_meet_path_minimum_msat {
1054 hit_minimum_limit = true;
1055 } else if over_path_minimum_msat {
1056 // Note that low contribution here (limited by available_liquidity_msat)
1057 // might violate htlc_minimum_msat on the hops which are next along the
1058 // payment path (upstream to the payee). To avoid that, we recompute
1059 // path fees knowing the final path contribution after constructing it.
1060 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
1061 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
1062 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
1063 .unwrap_or_else(|| u64::max_value());
1064 let hm_entry = dist.entry($src_node_id);
1065 let old_entry = hm_entry.or_insert_with(|| {
1066 // If there was previously no known way to access the source node
1067 // (recall it goes payee-to-payer) of short_channel_id, first add a
1068 // semi-dummy record just to compute the fees to reach the source node.
1069 // This will affect our decision on selecting short_channel_id
1070 // as a way to reach the $dest_node_id.
1071 let mut fee_base_msat = 0;
1072 let mut fee_proportional_millionths = 0;
1073 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
1074 fee_base_msat = fees.base_msat;
1075 fee_proportional_millionths = fees.proportional_millionths;
1078 node_id: $dest_node_id.clone(),
1079 candidate: $candidate.clone(),
1081 src_lowest_inbound_fees: RoutingFees {
1082 base_msat: fee_base_msat,
1083 proportional_millionths: fee_proportional_millionths,
1085 next_hops_fee_msat: u64::max_value(),
1086 hop_use_fee_msat: u64::max_value(),
1087 total_fee_msat: u64::max_value(),
1088 path_htlc_minimum_msat,
1089 path_penalty_msat: u64::max_value(),
1090 was_processed: false,
1091 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1092 value_contribution_msat,
1096 #[allow(unused_mut)] // We only use the mut in cfg(test)
1097 let mut should_process = !old_entry.was_processed;
1098 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1100 // In test/fuzzing builds, we do extra checks to make sure the skipping
1101 // of already-seen nodes only happens in cases we expect (see below).
1102 if !should_process { should_process = true; }
1106 let mut hop_use_fee_msat = 0;
1107 let mut total_fee_msat = $next_hops_fee_msat;
1109 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1110 // will have the same effective-fee
1111 if $src_node_id != our_node_id {
1112 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1113 // max_value means we'll always fail
1114 // the old_entry.total_fee_msat > total_fee_msat check
1115 None => total_fee_msat = u64::max_value(),
1117 hop_use_fee_msat = fee_msat;
1118 total_fee_msat += hop_use_fee_msat;
1119 // When calculating the lowest inbound fees to a node, we
1120 // calculate fees here not based on the actual value we think
1121 // will flow over this channel, but on the minimum value that
1122 // we'll accept flowing over it. The minimum accepted value
1123 // is a constant through each path collection run, ensuring
1124 // consistent basis. Otherwise we may later find a
1125 // different path to the source node that is more expensive,
1126 // but which we consider to be cheaper because we are capacity
1127 // constrained and the relative fee becomes lower.
1128 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1129 .map(|a| a.checked_add(total_fee_msat)) {
1134 total_fee_msat = u64::max_value();
1141 let channel_usage = ChannelUsage {
1142 amount_msat: amount_to_transfer_over_msat,
1143 inflight_htlc_msat: used_liquidity_msat,
1146 let channel_penalty_msat = scorer.channel_penalty_msat(
1147 short_channel_id, &$src_node_id, &$dest_node_id, channel_usage
1149 let path_penalty_msat = $next_hops_path_penalty_msat
1150 .saturating_add(channel_penalty_msat);
1151 let new_graph_node = RouteGraphNode {
1152 node_id: $src_node_id,
1153 lowest_fee_to_peer_through_node: total_fee_msat,
1154 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1155 total_cltv_delta: hop_total_cltv_delta,
1156 value_contribution_msat,
1157 path_htlc_minimum_msat,
1159 path_length_to_node,
1162 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1163 // if this way is cheaper than the already known
1164 // (considering the cost to "reach" this channel from the route destination,
1165 // the cost of using this channel,
1166 // and the cost of routing to the source node of this channel).
1167 // Also, consider that htlc_minimum_msat_difference, because we might end up
1168 // paying it. Consider the following exploit:
1169 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1170 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1171 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1172 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1174 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1175 // but it may require additional tracking - we don't want to double-count
1176 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1177 // can't use something that may decrease on future hops.
1178 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1179 .saturating_add(old_entry.path_penalty_msat);
1180 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1181 .saturating_add(path_penalty_msat);
1183 if !old_entry.was_processed && new_cost < old_cost {
1184 targets.push(new_graph_node);
1185 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1186 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1187 old_entry.total_fee_msat = total_fee_msat;
1188 old_entry.node_id = $dest_node_id.clone();
1189 old_entry.candidate = $candidate.clone();
1190 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1191 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1192 old_entry.path_penalty_msat = path_penalty_msat;
1193 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1195 old_entry.value_contribution_msat = value_contribution_msat;
1197 did_add_update_path_to_src_node = true;
1198 } else if old_entry.was_processed && new_cost < old_cost {
1199 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1201 // If we're skipping processing a node which was previously
1202 // processed even though we found another path to it with a
1203 // cheaper fee, check that it was because the second path we
1204 // found (which we are processing now) has a lower value
1205 // contribution due to an HTLC minimum limit.
1207 // e.g. take a graph with two paths from node 1 to node 2, one
1208 // through channel A, and one through channel B. Channel A and
1209 // B are both in the to-process heap, with their scores set by
1210 // a higher htlc_minimum than fee.
1211 // Channel A is processed first, and the channels onwards from
1212 // node 1 are added to the to-process heap. Thereafter, we pop
1213 // Channel B off of the heap, note that it has a much more
1214 // restrictive htlc_maximum_msat, and recalculate the fees for
1215 // all of node 1's channels using the new, reduced, amount.
1217 // This would be bogus - we'd be selecting a higher-fee path
1218 // with a lower htlc_maximum_msat instead of the one we'd
1219 // already decided to use.
1220 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1222 value_contribution_msat + path_penalty_msat <
1223 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1231 did_add_update_path_to_src_node
1235 let default_node_features = default_node_features();
1237 // Find ways (channels with destination) to reach a given node and store them
1238 // in the corresponding data structures (routing graph etc).
1239 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1240 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1241 // This data can later be helpful to optimize routing (pay lower fees).
1242 macro_rules! add_entries_to_cheapest_to_target_node {
1243 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1244 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1245 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1246 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1247 let was_processed = elem.was_processed;
1248 elem.was_processed = true;
1251 // Entries are added to dist in add_entry!() when there is a channel from a node.
1252 // Because there are no channels from payee, it will not have a dist entry at this point.
1253 // If we're processing any other node, it is always be the result of a channel from it.
1254 assert_eq!($node_id, payee_node_id);
1259 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1260 for details in first_channels {
1261 let candidate = CandidateRouteHop::FirstHop { details };
1262 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1263 $next_hops_value_contribution,
1264 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1265 $next_hops_cltv_delta, $next_hops_path_length);
1269 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1272 &default_node_features
1275 if !features.requires_unknown_bits() {
1276 for chan_id in $node.channels.iter() {
1277 let chan = network_channels.get(chan_id).unwrap();
1278 if !chan.features.requires_unknown_bits() {
1279 let (directed_channel, source) =
1280 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1281 if first_hops.is_none() || *source != our_node_id {
1282 if let Some(direction) = directed_channel.direction() {
1283 if direction.enabled {
1284 let candidate = CandidateRouteHop::PublicHop {
1285 info: directed_channel.with_update().unwrap(),
1286 short_channel_id: *chan_id,
1288 add_entry!(candidate, *source, $node_id,
1289 $fee_to_target_msat,
1290 $next_hops_value_contribution,
1291 $next_hops_path_htlc_minimum_msat,
1292 $next_hops_path_penalty_msat,
1293 $next_hops_cltv_delta, $next_hops_path_length);
1304 let mut payment_paths = Vec::<PaymentPath>::new();
1306 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1307 'paths_collection: loop {
1308 // For every new path, start from scratch, except for used_channel_liquidities, which
1309 // helps to avoid reusing previously selected paths in future iterations.
1312 hit_minimum_limit = false;
1314 // If first hop is a private channel and the only way to reach the payee, this is the only
1315 // place where it could be added.
1316 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1317 for details in first_channels {
1318 let candidate = CandidateRouteHop::FirstHop { details };
1319 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat,
1321 log_trace!(logger, "{} direct route to payee via SCID {}",
1322 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1326 // Add the payee as a target, so that the payee-to-payer
1327 // search algorithm knows what to start with.
1328 match network_nodes.get(&payee_node_id) {
1329 // The payee is not in our network graph, so nothing to add here.
1330 // There is still a chance of reaching them via last_hops though,
1331 // so don't yet fail the payment here.
1332 // If not, targets.pop() will not even let us enter the loop in step 2.
1335 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0, 0);
1340 // If a caller provided us with last hops, add them to routing targets. Since this happens
1341 // earlier than general path finding, they will be somewhat prioritized, although currently
1342 // it matters only if the fees are exactly the same.
1343 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1344 let first_hop_in_route = &(route.0)[0];
1345 let have_hop_src_in_graph =
1346 // Only add the hops in this route to our candidate set if either
1347 // we have a direct channel to the first hop or the first hop is
1348 // in the regular network graph.
1349 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1350 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1351 if have_hop_src_in_graph {
1352 // We start building the path from reverse, i.e., from payee
1353 // to the first RouteHintHop in the path.
1354 let hop_iter = route.0.iter().rev();
1355 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1356 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1357 let mut hop_used = true;
1358 let mut aggregate_next_hops_fee_msat: u64 = 0;
1359 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1360 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1361 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1362 let mut aggregate_next_hops_path_length: u8 = 0;
1364 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1365 let source = NodeId::from_pubkey(&hop.src_node_id);
1366 let target = NodeId::from_pubkey(&prev_hop_id);
1367 let candidate = network_channels
1368 .get(&hop.short_channel_id)
1369 .and_then(|channel| channel.as_directed_to(&target))
1370 .and_then(|(channel, _)| channel.with_update())
1371 .map(|info| CandidateRouteHop::PublicHop {
1373 short_channel_id: hop.short_channel_id,
1375 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1377 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat,
1378 path_value_msat, aggregate_next_hops_path_htlc_minimum_msat,
1379 aggregate_next_hops_path_penalty_msat,
1380 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length) {
1381 // If this hop was not used then there is no use checking the preceding
1382 // hops in the RouteHint. We can break by just searching for a direct
1383 // channel between last checked hop and first_hop_targets.
1387 let used_liquidity_msat = used_channel_liquidities
1388 .get(&(hop.short_channel_id, source < target)).copied().unwrap_or(0);
1389 let channel_usage = ChannelUsage {
1390 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
1391 inflight_htlc_msat: used_liquidity_msat,
1392 effective_capacity: candidate.effective_capacity(),
1394 let channel_penalty_msat = scorer.channel_penalty_msat(
1395 hop.short_channel_id, &source, &target, channel_usage
1397 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1398 .saturating_add(channel_penalty_msat);
1400 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1401 .saturating_add(hop.cltv_expiry_delta as u32);
1403 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1406 // Searching for a direct channel between last checked hop and first_hop_targets
1407 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1408 for details in first_channels {
1409 let candidate = CandidateRouteHop::FirstHop { details };
1410 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1411 aggregate_next_hops_fee_msat, path_value_msat,
1412 aggregate_next_hops_path_htlc_minimum_msat,
1413 aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta,
1414 aggregate_next_hops_path_length);
1422 // In the next values of the iterator, the aggregate fees already reflects
1423 // the sum of value sent from payer (final_value_msat) and routing fees
1424 // for the last node in the RouteHint. We need to just add the fees to
1425 // route through the current node so that the preceding node (next iteration)
1427 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1428 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1429 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1431 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1432 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1433 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1434 .checked_add(hop_htlc_minimum_msat_inc);
1435 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1437 if idx == route.0.len() - 1 {
1438 // The last hop in this iterator is the first hop in
1439 // overall RouteHint.
1440 // If this hop connects to a node with which we have a direct channel,
1441 // ignore the network graph and, if the last hop was added, add our
1442 // direct channel to the candidate set.
1444 // Note that we *must* check if the last hop was added as `add_entry`
1445 // always assumes that the third argument is a node to which we have a
1447 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1448 for details in first_channels {
1449 let candidate = CandidateRouteHop::FirstHop { details };
1450 add_entry!(candidate, our_node_id,
1451 NodeId::from_pubkey(&hop.src_node_id),
1452 aggregate_next_hops_fee_msat, path_value_msat,
1453 aggregate_next_hops_path_htlc_minimum_msat,
1454 aggregate_next_hops_path_penalty_msat,
1455 aggregate_next_hops_cltv_delta,
1456 aggregate_next_hops_path_length);
1464 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1466 // At this point, targets are filled with the data from first and
1467 // last hops communicated by the caller, and the payment receiver.
1468 let mut found_new_path = false;
1471 // If this loop terminates due the exhaustion of targets, two situations are possible:
1472 // - not enough outgoing liquidity:
1473 // 0 < already_collected_value_msat < final_value_msat
1474 // - enough outgoing liquidity:
1475 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1476 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1477 // paths_collection will be stopped because found_new_path==false.
1478 // This is not necessarily a routing failure.
1479 '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() {
1481 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1482 // traversing the graph and arrange the path out of what we found.
1483 if node_id == our_node_id {
1484 let mut new_entry = dist.remove(&our_node_id).unwrap();
1485 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1488 let mut features_set = false;
1489 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1490 for details in first_channels {
1491 if details.get_outbound_payment_scid().unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1492 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1493 features_set = true;
1499 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1500 if let Some(node_info) = node.announcement_info.as_ref() {
1501 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1503 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1506 // We can fill in features for everything except hops which were
1507 // provided via the invoice we're paying. We could guess based on the
1508 // recipient's features but for now we simply avoid guessing at all.
1512 // Means we succesfully traversed from the payer to the payee, now
1513 // save this path for the payment route. Also, update the liquidity
1514 // remaining on the used hops, so that we take them into account
1515 // while looking for more paths.
1516 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1520 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1521 Some(payment_hop) => payment_hop,
1522 // We can't arrive at None because, if we ever add an entry to targets,
1523 // we also fill in the entry in dist (see add_entry!).
1524 None => unreachable!(),
1526 // We "propagate" the fees one hop backward (topologically) here,
1527 // so that fees paid for a HTLC forwarding on the current channel are
1528 // associated with the previous channel (where they will be subtracted).
1529 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1530 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1532 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1533 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1535 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1536 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1538 let mut payment_path = PaymentPath {hops: ordered_hops};
1540 // We could have possibly constructed a slightly inconsistent path: since we reduce
1541 // value being transferred along the way, we could have violated htlc_minimum_msat
1542 // on some channels we already passed (assuming dest->source direction). Here, we
1543 // recompute the fees again, so that if that's the case, we match the currently
1544 // underpaid htlc_minimum_msat with fees.
1545 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
1546 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
1547 payment_path.update_value_and_recompute_fees(value_contribution_msat);
1549 // Since a path allows to transfer as much value as
1550 // the smallest channel it has ("bottleneck"), we should recompute
1551 // the fees so sender HTLC don't overpay fees when traversing
1552 // larger channels than the bottleneck. This may happen because
1553 // when we were selecting those channels we were not aware how much value
1554 // this path will transfer, and the relative fee for them
1555 // might have been computed considering a larger value.
1556 // Remember that we used these channels so that we don't rely
1557 // on the same liquidity in future paths.
1558 let mut prevented_redundant_path_selection = false;
1559 let prev_hop_iter = core::iter::once(&our_node_id)
1560 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
1561 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
1562 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
1563 let used_liquidity_msat = used_channel_liquidities
1564 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
1565 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
1566 .or_insert(spent_on_hop_msat);
1567 let hop_capacity = hop.candidate.effective_capacity();
1568 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
1569 if *used_liquidity_msat == hop_max_msat {
1570 // If this path used all of this channel's available liquidity, we know
1571 // this path will not be selected again in the next loop iteration.
1572 prevented_redundant_path_selection = true;
1574 debug_assert!(*used_liquidity_msat <= hop_max_msat);
1576 if !prevented_redundant_path_selection {
1577 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1578 // we'll probably end up picking the same path again on the next iteration.
1579 // Decrease the available liquidity of a hop in the middle of the path.
1580 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1581 let exhausted = u64::max_value();
1582 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1583 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
1584 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
1587 // Track the total amount all our collected paths allow to send so that we know
1588 // when to stop looking for more paths
1589 already_collected_value_msat += value_contribution_msat;
1591 payment_paths.push(payment_path);
1592 found_new_path = true;
1593 break 'path_construction;
1596 // If we found a path back to the payee, we shouldn't try to process it again. This is
1597 // the equivalent of the `elem.was_processed` check in
1598 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1599 if node_id == payee_node_id { continue 'path_construction; }
1601 // Otherwise, since the current target node is not us,
1602 // keep "unrolling" the payment graph from payee to payer by
1603 // finding a way to reach the current target from the payer side.
1604 match network_nodes.get(&node_id) {
1607 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
1608 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
1609 total_cltv_delta, path_length_to_node);
1615 if !found_new_path && channel_saturation_pow_half != 0 {
1616 channel_saturation_pow_half = 0;
1617 continue 'paths_collection;
1619 // If we don't support MPP, no use trying to gather more value ever.
1620 break 'paths_collection;
1624 // Stop either when the recommended value is reached or if no new path was found in this
1626 // In the latter case, making another path finding attempt won't help,
1627 // because we deterministically terminated the search due to low liquidity.
1628 if !found_new_path && channel_saturation_pow_half != 0 {
1629 channel_saturation_pow_half = 0;
1630 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1631 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1632 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1633 break 'paths_collection;
1634 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1635 // Further, if this was our first walk of the graph, and we weren't limited by an
1636 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1637 // limited by an htlc_minimum_msat value, find another path with a higher value,
1638 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1639 // still keeping a lower total fee than this path.
1640 if !hit_minimum_limit {
1641 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1642 break 'paths_collection;
1644 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1645 path_value_msat = recommended_value_msat;
1650 if payment_paths.len() == 0 {
1651 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1654 if already_collected_value_msat < final_value_msat {
1655 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1659 let mut selected_route = payment_paths;
1661 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
1662 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
1664 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
1665 // the value they contribute towards the payment amount.
1666 // We sort in descending order as we will remove from the front in `retain`, next.
1667 selected_route.sort_unstable_by(|a, b|
1668 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
1669 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
1672 // We should make sure that at least 1 path left.
1673 let mut paths_left = selected_route.len();
1674 selected_route.retain(|path| {
1675 if paths_left == 1 {
1678 let path_value_msat = path.get_value_msat();
1679 if path_value_msat <= overpaid_value_msat {
1680 overpaid_value_msat -= path_value_msat;
1686 debug_assert!(selected_route.len() > 0);
1688 if overpaid_value_msat != 0 {
1690 // Now, subtract the remaining overpaid value from the most-expensive path.
1691 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1692 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1693 selected_route.sort_unstable_by(|a, b| {
1694 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1695 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1696 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1698 let expensive_payment_path = selected_route.first_mut().unwrap();
1700 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
1701 // can't go negative.
1702 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1703 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1707 // Sort by the path itself and combine redundant paths.
1708 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
1709 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
1711 selected_route.sort_unstable_by_key(|path| {
1712 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
1713 debug_assert!(path.hops.len() <= key.len());
1714 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
1719 for idx in 0..(selected_route.len() - 1) {
1720 if idx + 1 >= selected_route.len() { break; }
1721 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
1722 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
1723 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
1724 selected_route[idx].update_value_and_recompute_fees(new_value);
1725 selected_route.remove(idx + 1);
1729 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1730 for payment_path in selected_route {
1731 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1733 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)})?,
1734 node_features: node_features.clone(),
1735 short_channel_id: payment_hop.candidate.short_channel_id(),
1736 channel_features: payment_hop.candidate.features(),
1737 fee_msat: payment_hop.fee_msat,
1738 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1740 }).collect::<Vec<_>>();
1741 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1742 // applicable for the previous hop.
1743 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1744 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1746 selected_paths.push(path);
1748 // Make sure we would never create a route with more paths than we allow.
1749 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
1751 if let Some(features) = &payment_params.features {
1752 for path in selected_paths.iter_mut() {
1753 if let Ok(route_hop) = path.last_mut().unwrap() {
1754 route_hop.node_features = features.to_context();
1760 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1761 payment_params: Some(payment_params.clone()),
1763 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1767 // When an adversarial intermediary node observes a payment, it may be able to infer its
1768 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1769 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1770 // payment path by adding a randomized 'shadow route' offset to the final hop.
1771 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
1772 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
1774 let network_channels = network_graph.channels();
1775 let network_nodes = network_graph.nodes();
1777 for path in route.paths.iter_mut() {
1778 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1780 // Remember the last three nodes of the random walk and avoid looping back on them.
1781 // Init with the last three nodes from the actual path, if possible.
1782 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1783 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1784 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1786 // Choose the last publicly known node as the starting point for the random walk.
1787 let mut cur_hop: Option<NodeId> = None;
1788 let mut path_nonce = [0u8; 12];
1789 if let Some(starting_hop) = path.iter().rev()
1790 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1791 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1792 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1795 // Init PRNG with the path-dependant nonce, which is static for private paths.
1796 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1797 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1799 // Pick a random path length in [1 .. 3]
1800 prng.process_in_place(&mut random_path_bytes);
1801 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1803 for random_hop in 0..random_walk_length {
1804 // If we don't find a suitable offset in the public network graph, we default to
1805 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1806 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1808 if let Some(cur_node_id) = cur_hop {
1809 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1810 // Randomly choose the next unvisited hop.
1811 prng.process_in_place(&mut random_path_bytes);
1812 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1813 .checked_rem(cur_node.channels.len())
1814 .and_then(|index| cur_node.channels.get(index))
1815 .and_then(|id| network_channels.get(id)) {
1816 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1817 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1818 nodes_to_avoid[random_hop] = *next_id;
1819 dir_info.direction().map(|channel_update_info| {
1820 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1821 cur_hop = Some(*next_id);
1829 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1830 .checked_add(random_hop_offset)
1831 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1834 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1835 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1836 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1838 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1839 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1840 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1841 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1842 max_path_offset = cmp::max(
1843 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1844 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1845 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1847 // Add 'shadow' CLTV offset to the final hop
1848 if let Some(last_hop) = path.last_mut() {
1849 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1850 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1855 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
1856 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
1858 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
1859 pub fn build_route_from_hops<L: Deref, GL: Deref>(
1860 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
1861 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
1862 ) -> Result<Route, LightningError>
1863 where L::Target: Logger, GL::Target: Logger {
1864 let graph_lock = network_graph.read_only();
1865 let mut route = build_route_from_hops_internal(
1866 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
1867 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
1868 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1872 fn build_route_from_hops_internal<L: Deref>(
1873 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
1874 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
1875 logger: L, random_seed_bytes: &[u8; 32]
1876 ) -> Result<Route, LightningError> where L::Target: Logger {
1879 our_node_id: NodeId,
1880 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
1883 impl Score for HopScorer {
1884 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
1885 _usage: ChannelUsage) -> u64
1887 let mut cur_id = self.our_node_id;
1888 for i in 0..self.hop_ids.len() {
1889 if let Some(next_id) = self.hop_ids[i] {
1890 if cur_id == *source && next_id == *target {
1901 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1903 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
1905 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1907 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
1910 impl<'a> Writeable for HopScorer {
1912 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
1917 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
1918 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
1921 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
1922 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
1923 for i in 0..hops.len() {
1924 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
1927 let scorer = HopScorer { our_node_id, hop_ids };
1929 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
1930 final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)
1935 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
1936 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
1937 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
1938 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
1939 use crate::routing::scoring::{ChannelUsage, Score, ProbabilisticScorer, ProbabilisticScoringParameters};
1940 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
1941 use crate::chain::transaction::OutPoint;
1942 use crate::chain::keysinterface::KeysInterface;
1943 use crate::ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
1944 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
1945 use crate::ln::channelmanager;
1946 use crate::util::test_utils as ln_test_utils;
1947 use crate::util::chacha20::ChaCha20;
1949 use crate::util::ser::{Writeable, Writer};
1951 use bitcoin::hashes::Hash;
1952 use bitcoin::network::constants::Network;
1953 use bitcoin::blockdata::constants::genesis_block;
1954 use bitcoin::blockdata::script::Builder;
1955 use bitcoin::blockdata::opcodes;
1956 use bitcoin::blockdata::transaction::TxOut;
1960 use bitcoin::secp256k1::{PublicKey,SecretKey};
1961 use bitcoin::secp256k1::Secp256k1;
1963 use crate::prelude::*;
1964 use crate::sync::Arc;
1966 use core::convert::TryInto;
1968 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1969 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1970 channelmanager::ChannelDetails {
1971 channel_id: [0; 32],
1972 counterparty: channelmanager::ChannelCounterparty {
1975 unspendable_punishment_reserve: 0,
1976 forwarding_info: None,
1977 outbound_htlc_minimum_msat: None,
1978 outbound_htlc_maximum_msat: None,
1980 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1983 outbound_scid_alias: None,
1984 inbound_scid_alias: None,
1985 channel_value_satoshis: 0,
1988 outbound_capacity_msat,
1989 next_outbound_htlc_limit_msat: outbound_capacity_msat,
1990 inbound_capacity_msat: 42,
1991 unspendable_punishment_reserve: None,
1992 confirmations_required: None,
1993 force_close_spend_delay: None,
1994 is_outbound: true, is_channel_ready: true,
1995 is_usable: true, is_public: true,
1996 inbound_htlc_minimum_msat: None,
1997 inbound_htlc_maximum_msat: None,
2003 fn simple_route_test() {
2004 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2005 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2006 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2007 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2008 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2009 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2011 // Simple route to 2 via 1
2013 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) {
2014 assert_eq!(err, "Cannot send a payment of 0 msat");
2015 } else { panic!(); }
2017 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2018 assert_eq!(route.paths[0].len(), 2);
2020 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2021 assert_eq!(route.paths[0][0].short_channel_id, 2);
2022 assert_eq!(route.paths[0][0].fee_msat, 100);
2023 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2024 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2025 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2027 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2028 assert_eq!(route.paths[0][1].short_channel_id, 4);
2029 assert_eq!(route.paths[0][1].fee_msat, 100);
2030 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2031 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2032 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2036 fn invalid_first_hop_test() {
2037 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2038 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2039 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2040 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2041 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2042 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2044 // Simple route to 2 via 1
2046 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2048 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2049 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) {
2050 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2051 } else { panic!(); }
2053 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2054 assert_eq!(route.paths[0].len(), 2);
2058 fn htlc_minimum_test() {
2059 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2060 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2061 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2062 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2063 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2064 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2066 // Simple route to 2 via 1
2068 // Disable other paths
2069 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2070 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2071 short_channel_id: 12,
2073 flags: 2, // to disable
2074 cltv_expiry_delta: 0,
2075 htlc_minimum_msat: 0,
2076 htlc_maximum_msat: MAX_VALUE_MSAT,
2078 fee_proportional_millionths: 0,
2079 excess_data: Vec::new()
2081 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2082 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2083 short_channel_id: 3,
2085 flags: 2, // to disable
2086 cltv_expiry_delta: 0,
2087 htlc_minimum_msat: 0,
2088 htlc_maximum_msat: MAX_VALUE_MSAT,
2090 fee_proportional_millionths: 0,
2091 excess_data: Vec::new()
2093 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2094 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2095 short_channel_id: 13,
2097 flags: 2, // to disable
2098 cltv_expiry_delta: 0,
2099 htlc_minimum_msat: 0,
2100 htlc_maximum_msat: MAX_VALUE_MSAT,
2102 fee_proportional_millionths: 0,
2103 excess_data: Vec::new()
2105 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2106 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2107 short_channel_id: 6,
2109 flags: 2, // to disable
2110 cltv_expiry_delta: 0,
2111 htlc_minimum_msat: 0,
2112 htlc_maximum_msat: MAX_VALUE_MSAT,
2114 fee_proportional_millionths: 0,
2115 excess_data: Vec::new()
2117 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2118 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2119 short_channel_id: 7,
2121 flags: 2, // to disable
2122 cltv_expiry_delta: 0,
2123 htlc_minimum_msat: 0,
2124 htlc_maximum_msat: MAX_VALUE_MSAT,
2126 fee_proportional_millionths: 0,
2127 excess_data: Vec::new()
2130 // Check against amount_to_transfer_over_msat.
2131 // Set minimal HTLC of 200_000_000 msat.
2132 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2133 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2134 short_channel_id: 2,
2137 cltv_expiry_delta: 0,
2138 htlc_minimum_msat: 200_000_000,
2139 htlc_maximum_msat: MAX_VALUE_MSAT,
2141 fee_proportional_millionths: 0,
2142 excess_data: Vec::new()
2145 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2147 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2148 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2149 short_channel_id: 4,
2152 cltv_expiry_delta: 0,
2153 htlc_minimum_msat: 0,
2154 htlc_maximum_msat: 199_999_999,
2156 fee_proportional_millionths: 0,
2157 excess_data: Vec::new()
2160 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2161 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) {
2162 assert_eq!(err, "Failed to find a path to the given destination");
2163 } else { panic!(); }
2165 // Lift the restriction on the first hop.
2166 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2167 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2168 short_channel_id: 2,
2171 cltv_expiry_delta: 0,
2172 htlc_minimum_msat: 0,
2173 htlc_maximum_msat: MAX_VALUE_MSAT,
2175 fee_proportional_millionths: 0,
2176 excess_data: Vec::new()
2179 // A payment above the minimum should pass
2180 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();
2181 assert_eq!(route.paths[0].len(), 2);
2185 fn htlc_minimum_overpay_test() {
2186 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2187 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2188 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
2189 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2190 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2191 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2193 // A route to node#2 via two paths.
2194 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2195 // Thus, they can't send 60 without overpaying.
2196 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2197 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2198 short_channel_id: 2,
2201 cltv_expiry_delta: 0,
2202 htlc_minimum_msat: 35_000,
2203 htlc_maximum_msat: 40_000,
2205 fee_proportional_millionths: 0,
2206 excess_data: Vec::new()
2208 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2209 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2210 short_channel_id: 12,
2213 cltv_expiry_delta: 0,
2214 htlc_minimum_msat: 35_000,
2215 htlc_maximum_msat: 40_000,
2217 fee_proportional_millionths: 0,
2218 excess_data: Vec::new()
2222 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2223 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2224 short_channel_id: 13,
2227 cltv_expiry_delta: 0,
2228 htlc_minimum_msat: 0,
2229 htlc_maximum_msat: MAX_VALUE_MSAT,
2231 fee_proportional_millionths: 0,
2232 excess_data: Vec::new()
2234 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2235 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2236 short_channel_id: 4,
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()
2247 // Disable other paths
2248 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2249 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2250 short_channel_id: 1,
2252 flags: 2, // to disable
2253 cltv_expiry_delta: 0,
2254 htlc_minimum_msat: 0,
2255 htlc_maximum_msat: MAX_VALUE_MSAT,
2257 fee_proportional_millionths: 0,
2258 excess_data: Vec::new()
2261 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2262 // Overpay fees to hit htlc_minimum_msat.
2263 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2264 // TODO: this could be better balanced to overpay 10k and not 15k.
2265 assert_eq!(overpaid_fees, 15_000);
2267 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2268 // while taking even more fee to match htlc_minimum_msat.
2269 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2270 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2271 short_channel_id: 12,
2274 cltv_expiry_delta: 0,
2275 htlc_minimum_msat: 65_000,
2276 htlc_maximum_msat: 80_000,
2278 fee_proportional_millionths: 0,
2279 excess_data: Vec::new()
2281 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2282 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2283 short_channel_id: 2,
2286 cltv_expiry_delta: 0,
2287 htlc_minimum_msat: 0,
2288 htlc_maximum_msat: MAX_VALUE_MSAT,
2290 fee_proportional_millionths: 0,
2291 excess_data: Vec::new()
2293 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2294 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2295 short_channel_id: 4,
2298 cltv_expiry_delta: 0,
2299 htlc_minimum_msat: 0,
2300 htlc_maximum_msat: MAX_VALUE_MSAT,
2302 fee_proportional_millionths: 100_000,
2303 excess_data: Vec::new()
2306 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2307 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2308 assert_eq!(route.paths.len(), 1);
2309 assert_eq!(route.paths[0][0].short_channel_id, 12);
2310 let fees = route.paths[0][0].fee_msat;
2311 assert_eq!(fees, 5_000);
2313 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2314 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2315 // the other channel.
2316 assert_eq!(route.paths.len(), 1);
2317 assert_eq!(route.paths[0][0].short_channel_id, 2);
2318 let fees = route.paths[0][0].fee_msat;
2319 assert_eq!(fees, 5_000);
2323 fn disable_channels_test() {
2324 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2325 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2326 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2327 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2328 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2329 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2331 // // Disable channels 4 and 12 by flags=2
2332 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2333 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2334 short_channel_id: 4,
2336 flags: 2, // to disable
2337 cltv_expiry_delta: 0,
2338 htlc_minimum_msat: 0,
2339 htlc_maximum_msat: MAX_VALUE_MSAT,
2341 fee_proportional_millionths: 0,
2342 excess_data: Vec::new()
2344 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2345 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2346 short_channel_id: 12,
2348 flags: 2, // to disable
2349 cltv_expiry_delta: 0,
2350 htlc_minimum_msat: 0,
2351 htlc_maximum_msat: MAX_VALUE_MSAT,
2353 fee_proportional_millionths: 0,
2354 excess_data: Vec::new()
2357 // If all the channels require some features we don't understand, route should fail
2358 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) {
2359 assert_eq!(err, "Failed to find a path to the given destination");
2360 } else { panic!(); }
2362 // If we specify a channel to node7, that overrides our local channel view and that gets used
2363 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2364 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();
2365 assert_eq!(route.paths[0].len(), 2);
2367 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2368 assert_eq!(route.paths[0][0].short_channel_id, 42);
2369 assert_eq!(route.paths[0][0].fee_msat, 200);
2370 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2371 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2372 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2374 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2375 assert_eq!(route.paths[0][1].short_channel_id, 13);
2376 assert_eq!(route.paths[0][1].fee_msat, 100);
2377 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2378 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2379 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2383 fn disable_node_test() {
2384 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2385 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2386 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2387 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2388 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2389 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2391 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2392 let mut unknown_features = NodeFeatures::empty();
2393 unknown_features.set_unknown_feature_required();
2394 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2395 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2396 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2398 // If all nodes require some features we don't understand, route should fail
2399 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) {
2400 assert_eq!(err, "Failed to find a path to the given destination");
2401 } else { panic!(); }
2403 // If we specify a channel to node7, that overrides our local channel view and that gets used
2404 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2405 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();
2406 assert_eq!(route.paths[0].len(), 2);
2408 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2409 assert_eq!(route.paths[0][0].short_channel_id, 42);
2410 assert_eq!(route.paths[0][0].fee_msat, 200);
2411 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2412 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2413 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2415 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2416 assert_eq!(route.paths[0][1].short_channel_id, 13);
2417 assert_eq!(route.paths[0][1].fee_msat, 100);
2418 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2419 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2420 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2422 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2423 // naively) assume that the user checked the feature bits on the invoice, which override
2424 // the node_announcement.
2428 fn our_chans_test() {
2429 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2430 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2431 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2432 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2433 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2435 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2436 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2437 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2438 assert_eq!(route.paths[0].len(), 3);
2440 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2441 assert_eq!(route.paths[0][0].short_channel_id, 2);
2442 assert_eq!(route.paths[0][0].fee_msat, 200);
2443 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2444 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2445 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2447 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2448 assert_eq!(route.paths[0][1].short_channel_id, 4);
2449 assert_eq!(route.paths[0][1].fee_msat, 100);
2450 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2451 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2452 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2454 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2455 assert_eq!(route.paths[0][2].short_channel_id, 3);
2456 assert_eq!(route.paths[0][2].fee_msat, 100);
2457 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2458 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2459 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2461 // If we specify a channel to node7, that overrides our local channel view and that gets used
2462 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2463 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2464 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();
2465 assert_eq!(route.paths[0].len(), 2);
2467 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2468 assert_eq!(route.paths[0][0].short_channel_id, 42);
2469 assert_eq!(route.paths[0][0].fee_msat, 200);
2470 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2471 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2472 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2474 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2475 assert_eq!(route.paths[0][1].short_channel_id, 13);
2476 assert_eq!(route.paths[0][1].fee_msat, 100);
2477 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2478 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2479 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2482 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2483 let zero_fees = RoutingFees {
2485 proportional_millionths: 0,
2487 vec![RouteHint(vec![RouteHintHop {
2488 src_node_id: nodes[3],
2489 short_channel_id: 8,
2491 cltv_expiry_delta: (8 << 4) | 1,
2492 htlc_minimum_msat: None,
2493 htlc_maximum_msat: None,
2495 ]), RouteHint(vec![RouteHintHop {
2496 src_node_id: nodes[4],
2497 short_channel_id: 9,
2500 proportional_millionths: 0,
2502 cltv_expiry_delta: (9 << 4) | 1,
2503 htlc_minimum_msat: None,
2504 htlc_maximum_msat: None,
2505 }]), RouteHint(vec![RouteHintHop {
2506 src_node_id: nodes[5],
2507 short_channel_id: 10,
2509 cltv_expiry_delta: (10 << 4) | 1,
2510 htlc_minimum_msat: None,
2511 htlc_maximum_msat: None,
2515 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2516 let zero_fees = RoutingFees {
2518 proportional_millionths: 0,
2520 vec![RouteHint(vec![RouteHintHop {
2521 src_node_id: nodes[2],
2522 short_channel_id: 5,
2525 proportional_millionths: 0,
2527 cltv_expiry_delta: (5 << 4) | 1,
2528 htlc_minimum_msat: None,
2529 htlc_maximum_msat: None,
2531 src_node_id: nodes[3],
2532 short_channel_id: 8,
2534 cltv_expiry_delta: (8 << 4) | 1,
2535 htlc_minimum_msat: None,
2536 htlc_maximum_msat: None,
2538 ]), RouteHint(vec![RouteHintHop {
2539 src_node_id: nodes[4],
2540 short_channel_id: 9,
2543 proportional_millionths: 0,
2545 cltv_expiry_delta: (9 << 4) | 1,
2546 htlc_minimum_msat: None,
2547 htlc_maximum_msat: None,
2548 }]), RouteHint(vec![RouteHintHop {
2549 src_node_id: nodes[5],
2550 short_channel_id: 10,
2552 cltv_expiry_delta: (10 << 4) | 1,
2553 htlc_minimum_msat: None,
2554 htlc_maximum_msat: None,
2559 fn partial_route_hint_test() {
2560 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2561 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2562 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2563 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2564 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2566 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2567 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2568 // RouteHint may be partially used by the algo to build the best path.
2570 // First check that last hop can't have its source as the payee.
2571 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2572 src_node_id: nodes[6],
2573 short_channel_id: 8,
2576 proportional_millionths: 0,
2578 cltv_expiry_delta: (8 << 4) | 1,
2579 htlc_minimum_msat: None,
2580 htlc_maximum_msat: None,
2583 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2584 invalid_last_hops.push(invalid_last_hop);
2586 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2587 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) {
2588 assert_eq!(err, "Route hint cannot have the payee as the source.");
2589 } else { panic!(); }
2592 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2593 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2594 assert_eq!(route.paths[0].len(), 5);
2596 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2597 assert_eq!(route.paths[0][0].short_channel_id, 2);
2598 assert_eq!(route.paths[0][0].fee_msat, 100);
2599 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2600 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2601 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2603 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2604 assert_eq!(route.paths[0][1].short_channel_id, 4);
2605 assert_eq!(route.paths[0][1].fee_msat, 0);
2606 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2607 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2608 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2610 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2611 assert_eq!(route.paths[0][2].short_channel_id, 6);
2612 assert_eq!(route.paths[0][2].fee_msat, 0);
2613 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2614 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2615 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2617 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2618 assert_eq!(route.paths[0][3].short_channel_id, 11);
2619 assert_eq!(route.paths[0][3].fee_msat, 0);
2620 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2621 // If we have a peer in the node map, we'll use their features here since we don't have
2622 // a way of figuring out their features from the invoice:
2623 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2624 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2626 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2627 assert_eq!(route.paths[0][4].short_channel_id, 8);
2628 assert_eq!(route.paths[0][4].fee_msat, 100);
2629 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2630 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2631 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2634 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2635 let zero_fees = RoutingFees {
2637 proportional_millionths: 0,
2639 vec![RouteHint(vec![RouteHintHop {
2640 src_node_id: nodes[3],
2641 short_channel_id: 8,
2643 cltv_expiry_delta: (8 << 4) | 1,
2644 htlc_minimum_msat: None,
2645 htlc_maximum_msat: None,
2646 }]), RouteHint(vec![
2648 ]), RouteHint(vec![RouteHintHop {
2649 src_node_id: nodes[5],
2650 short_channel_id: 10,
2652 cltv_expiry_delta: (10 << 4) | 1,
2653 htlc_minimum_msat: None,
2654 htlc_maximum_msat: None,
2659 fn ignores_empty_last_hops_test() {
2660 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2661 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2662 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2663 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2664 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2665 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2667 // Test handling of an empty RouteHint passed in Invoice.
2669 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2670 assert_eq!(route.paths[0].len(), 5);
2672 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2673 assert_eq!(route.paths[0][0].short_channel_id, 2);
2674 assert_eq!(route.paths[0][0].fee_msat, 100);
2675 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2676 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2677 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2679 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2680 assert_eq!(route.paths[0][1].short_channel_id, 4);
2681 assert_eq!(route.paths[0][1].fee_msat, 0);
2682 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2683 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2684 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2686 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2687 assert_eq!(route.paths[0][2].short_channel_id, 6);
2688 assert_eq!(route.paths[0][2].fee_msat, 0);
2689 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2690 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2691 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2693 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2694 assert_eq!(route.paths[0][3].short_channel_id, 11);
2695 assert_eq!(route.paths[0][3].fee_msat, 0);
2696 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2697 // If we have a peer in the node map, we'll use their features here since we don't have
2698 // a way of figuring out their features from the invoice:
2699 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2700 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2702 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2703 assert_eq!(route.paths[0][4].short_channel_id, 8);
2704 assert_eq!(route.paths[0][4].fee_msat, 100);
2705 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2706 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2707 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2710 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2712 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2713 let zero_fees = RoutingFees {
2715 proportional_millionths: 0,
2717 vec![RouteHint(vec![RouteHintHop {
2718 src_node_id: hint_hops[0],
2719 short_channel_id: 0xff00,
2722 proportional_millionths: 0,
2724 cltv_expiry_delta: (5 << 4) | 1,
2725 htlc_minimum_msat: None,
2726 htlc_maximum_msat: None,
2728 src_node_id: hint_hops[1],
2729 short_channel_id: 0xff01,
2731 cltv_expiry_delta: (8 << 4) | 1,
2732 htlc_minimum_msat: None,
2733 htlc_maximum_msat: None,
2738 fn multi_hint_last_hops_test() {
2739 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2740 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2741 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2742 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2743 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2744 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2745 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2746 // Test through channels 2, 3, 0xff00, 0xff01.
2747 // Test shows that multiple hop hints are considered.
2749 // Disabling channels 6 & 7 by flags=2
2750 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2751 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2752 short_channel_id: 6,
2754 flags: 2, // to disable
2755 cltv_expiry_delta: 0,
2756 htlc_minimum_msat: 0,
2757 htlc_maximum_msat: MAX_VALUE_MSAT,
2759 fee_proportional_millionths: 0,
2760 excess_data: Vec::new()
2762 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2763 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2764 short_channel_id: 7,
2766 flags: 2, // to disable
2767 cltv_expiry_delta: 0,
2768 htlc_minimum_msat: 0,
2769 htlc_maximum_msat: MAX_VALUE_MSAT,
2771 fee_proportional_millionths: 0,
2772 excess_data: Vec::new()
2775 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2776 assert_eq!(route.paths[0].len(), 4);
2778 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2779 assert_eq!(route.paths[0][0].short_channel_id, 2);
2780 assert_eq!(route.paths[0][0].fee_msat, 200);
2781 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2782 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2783 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2785 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2786 assert_eq!(route.paths[0][1].short_channel_id, 4);
2787 assert_eq!(route.paths[0][1].fee_msat, 100);
2788 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2789 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2790 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2792 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2793 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2794 assert_eq!(route.paths[0][2].fee_msat, 0);
2795 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2796 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2797 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2799 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2800 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2801 assert_eq!(route.paths[0][3].fee_msat, 100);
2802 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2803 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2804 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2808 fn private_multi_hint_last_hops_test() {
2809 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2810 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2812 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
2813 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
2815 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
2816 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2817 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2818 // Test through channels 2, 3, 0xff00, 0xff01.
2819 // Test shows that multiple hop hints are considered.
2821 // Disabling channels 6 & 7 by flags=2
2822 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2823 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2824 short_channel_id: 6,
2826 flags: 2, // to disable
2827 cltv_expiry_delta: 0,
2828 htlc_minimum_msat: 0,
2829 htlc_maximum_msat: MAX_VALUE_MSAT,
2831 fee_proportional_millionths: 0,
2832 excess_data: Vec::new()
2834 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2835 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2836 short_channel_id: 7,
2838 flags: 2, // to disable
2839 cltv_expiry_delta: 0,
2840 htlc_minimum_msat: 0,
2841 htlc_maximum_msat: MAX_VALUE_MSAT,
2843 fee_proportional_millionths: 0,
2844 excess_data: Vec::new()
2847 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
2848 assert_eq!(route.paths[0].len(), 4);
2850 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2851 assert_eq!(route.paths[0][0].short_channel_id, 2);
2852 assert_eq!(route.paths[0][0].fee_msat, 200);
2853 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2854 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2855 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2857 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2858 assert_eq!(route.paths[0][1].short_channel_id, 4);
2859 assert_eq!(route.paths[0][1].fee_msat, 100);
2860 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2861 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2862 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2864 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
2865 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2866 assert_eq!(route.paths[0][2].fee_msat, 0);
2867 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2868 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2869 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2871 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2872 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2873 assert_eq!(route.paths[0][3].fee_msat, 100);
2874 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2875 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2876 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2879 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2880 let zero_fees = RoutingFees {
2882 proportional_millionths: 0,
2884 vec![RouteHint(vec![RouteHintHop {
2885 src_node_id: nodes[4],
2886 short_channel_id: 11,
2888 cltv_expiry_delta: (11 << 4) | 1,
2889 htlc_minimum_msat: None,
2890 htlc_maximum_msat: None,
2892 src_node_id: nodes[3],
2893 short_channel_id: 8,
2895 cltv_expiry_delta: (8 << 4) | 1,
2896 htlc_minimum_msat: None,
2897 htlc_maximum_msat: None,
2898 }]), RouteHint(vec![RouteHintHop {
2899 src_node_id: nodes[4],
2900 short_channel_id: 9,
2903 proportional_millionths: 0,
2905 cltv_expiry_delta: (9 << 4) | 1,
2906 htlc_minimum_msat: None,
2907 htlc_maximum_msat: None,
2908 }]), RouteHint(vec![RouteHintHop {
2909 src_node_id: nodes[5],
2910 short_channel_id: 10,
2912 cltv_expiry_delta: (10 << 4) | 1,
2913 htlc_minimum_msat: None,
2914 htlc_maximum_msat: None,
2919 fn last_hops_with_public_channel_test() {
2920 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2921 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2922 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
2923 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2924 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2925 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2926 // This test shows that public routes can be present in the invoice
2927 // which would be handled in the same manner.
2929 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2930 assert_eq!(route.paths[0].len(), 5);
2932 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2933 assert_eq!(route.paths[0][0].short_channel_id, 2);
2934 assert_eq!(route.paths[0][0].fee_msat, 100);
2935 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2936 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2937 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2939 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2940 assert_eq!(route.paths[0][1].short_channel_id, 4);
2941 assert_eq!(route.paths[0][1].fee_msat, 0);
2942 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2943 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2944 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2946 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2947 assert_eq!(route.paths[0][2].short_channel_id, 6);
2948 assert_eq!(route.paths[0][2].fee_msat, 0);
2949 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2950 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2951 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2953 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2954 assert_eq!(route.paths[0][3].short_channel_id, 11);
2955 assert_eq!(route.paths[0][3].fee_msat, 0);
2956 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2957 // If we have a peer in the node map, we'll use their features here since we don't have
2958 // a way of figuring out their features from the invoice:
2959 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2960 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2962 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2963 assert_eq!(route.paths[0][4].short_channel_id, 8);
2964 assert_eq!(route.paths[0][4].fee_msat, 100);
2965 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2966 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2967 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2971 fn our_chans_last_hop_connect_test() {
2972 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2973 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2974 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2975 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2976 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2978 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
2979 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2980 let mut last_hops = last_hops(&nodes);
2981 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2982 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();
2983 assert_eq!(route.paths[0].len(), 2);
2985 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
2986 assert_eq!(route.paths[0][0].short_channel_id, 42);
2987 assert_eq!(route.paths[0][0].fee_msat, 0);
2988 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
2989 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2990 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2992 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
2993 assert_eq!(route.paths[0][1].short_channel_id, 8);
2994 assert_eq!(route.paths[0][1].fee_msat, 100);
2995 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2996 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2997 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2999 last_hops[0].0[0].fees.base_msat = 1000;
3001 // Revert to via 6 as the fee on 8 goes up
3002 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3003 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3004 assert_eq!(route.paths[0].len(), 4);
3006 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3007 assert_eq!(route.paths[0][0].short_channel_id, 2);
3008 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3009 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3010 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3011 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3013 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3014 assert_eq!(route.paths[0][1].short_channel_id, 4);
3015 assert_eq!(route.paths[0][1].fee_msat, 100);
3016 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3017 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3018 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3020 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3021 assert_eq!(route.paths[0][2].short_channel_id, 7);
3022 assert_eq!(route.paths[0][2].fee_msat, 0);
3023 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3024 // If we have a peer in the node map, we'll use their features here since we don't have
3025 // a way of figuring out their features from the invoice:
3026 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3027 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3029 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3030 assert_eq!(route.paths[0][3].short_channel_id, 10);
3031 assert_eq!(route.paths[0][3].fee_msat, 100);
3032 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3033 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3034 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3036 // ...but still use 8 for larger payments as 6 has a variable feerate
3037 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3038 assert_eq!(route.paths[0].len(), 5);
3040 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3041 assert_eq!(route.paths[0][0].short_channel_id, 2);
3042 assert_eq!(route.paths[0][0].fee_msat, 3000);
3043 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3044 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3045 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3047 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3048 assert_eq!(route.paths[0][1].short_channel_id, 4);
3049 assert_eq!(route.paths[0][1].fee_msat, 0);
3050 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3051 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3052 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3054 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3055 assert_eq!(route.paths[0][2].short_channel_id, 6);
3056 assert_eq!(route.paths[0][2].fee_msat, 0);
3057 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3058 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3059 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3061 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3062 assert_eq!(route.paths[0][3].short_channel_id, 11);
3063 assert_eq!(route.paths[0][3].fee_msat, 1000);
3064 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3065 // If we have a peer in the node map, we'll use their features here since we don't have
3066 // a way of figuring out their features from the invoice:
3067 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3068 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3070 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3071 assert_eq!(route.paths[0][4].short_channel_id, 8);
3072 assert_eq!(route.paths[0][4].fee_msat, 2000);
3073 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3074 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3075 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3078 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> {
3079 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3080 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3081 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3083 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3084 let last_hops = RouteHint(vec![RouteHintHop {
3085 src_node_id: middle_node_id,
3086 short_channel_id: 8,
3089 proportional_millionths: last_hop_fee_prop,
3091 cltv_expiry_delta: (8 << 4) | 1,
3092 htlc_minimum_msat: None,
3093 htlc_maximum_msat: last_hop_htlc_max,
3095 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3096 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3097 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3098 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3099 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3100 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
3101 let logger = ln_test_utils::TestLogger::new();
3102 let network_graph = NetworkGraph::new(genesis_hash, &logger);
3103 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3104 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
3109 fn unannounced_path_test() {
3110 // We should be able to send a payment to a destination without any help of a routing graph
3111 // if we have a channel with a common counterparty that appears in the first and last hop
3113 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3115 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3116 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3117 assert_eq!(route.paths[0].len(), 2);
3119 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3120 assert_eq!(route.paths[0][0].short_channel_id, 42);
3121 assert_eq!(route.paths[0][0].fee_msat, 1001);
3122 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3123 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3124 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3126 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3127 assert_eq!(route.paths[0][1].short_channel_id, 8);
3128 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3129 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3130 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3131 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3135 fn overflow_unannounced_path_test_liquidity_underflow() {
3136 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3137 // the last-hop had a fee which overflowed a u64, we'd panic.
3138 // This was due to us adding the first-hop from us unconditionally, causing us to think
3139 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3140 // In this test, we previously hit a subtraction underflow due to having less available
3141 // liquidity at the last hop than 0.
3142 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());
3146 fn overflow_unannounced_path_test_feerate_overflow() {
3147 // This tests for the same case as above, except instead of hitting a subtraction
3148 // underflow, we hit a case where the fee charged at a hop overflowed.
3149 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());
3153 fn available_amount_while_routing_test() {
3154 // Tests whether we choose the correct available channel amount while routing.
3156 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3157 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3158 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3159 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3160 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3161 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
3163 // We will use a simple single-path route from
3164 // our node to node2 via node0: channels {1, 3}.
3166 // First disable all other paths.
3167 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3168 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3169 short_channel_id: 2,
3172 cltv_expiry_delta: 0,
3173 htlc_minimum_msat: 0,
3174 htlc_maximum_msat: 100_000,
3176 fee_proportional_millionths: 0,
3177 excess_data: Vec::new()
3179 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3180 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3181 short_channel_id: 12,
3184 cltv_expiry_delta: 0,
3185 htlc_minimum_msat: 0,
3186 htlc_maximum_msat: 100_000,
3188 fee_proportional_millionths: 0,
3189 excess_data: Vec::new()
3192 // Make the first channel (#1) very permissive,
3193 // and we will be testing all limits on the second channel.
3194 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3195 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3196 short_channel_id: 1,
3199 cltv_expiry_delta: 0,
3200 htlc_minimum_msat: 0,
3201 htlc_maximum_msat: 1_000_000_000,
3203 fee_proportional_millionths: 0,
3204 excess_data: Vec::new()
3207 // First, let's see if routing works if we have absolutely no idea about the available amount.
3208 // In this case, it should be set to 250_000 sats.
3209 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3210 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3211 short_channel_id: 3,
3214 cltv_expiry_delta: 0,
3215 htlc_minimum_msat: 0,
3216 htlc_maximum_msat: 250_000_000,
3218 fee_proportional_millionths: 0,
3219 excess_data: Vec::new()
3223 // Attempt to route more than available results in a failure.
3224 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3225 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3226 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3227 } else { panic!(); }
3231 // Now, attempt to route an exact amount we have should be fine.
3232 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();
3233 assert_eq!(route.paths.len(), 1);
3234 let path = route.paths.last().unwrap();
3235 assert_eq!(path.len(), 2);
3236 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3237 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3240 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3241 // Disable channel #1 and use another first hop.
3242 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3243 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3244 short_channel_id: 1,
3247 cltv_expiry_delta: 0,
3248 htlc_minimum_msat: 0,
3249 htlc_maximum_msat: 1_000_000_000,
3251 fee_proportional_millionths: 0,
3252 excess_data: Vec::new()
3255 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3256 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3259 // Attempt to route more than available results in a failure.
3260 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3261 &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) {
3262 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3263 } else { panic!(); }
3267 // Now, attempt to route an exact amount we have should be fine.
3268 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();
3269 assert_eq!(route.paths.len(), 1);
3270 let path = route.paths.last().unwrap();
3271 assert_eq!(path.len(), 2);
3272 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3273 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3276 // Enable channel #1 back.
3277 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3278 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3279 short_channel_id: 1,
3282 cltv_expiry_delta: 0,
3283 htlc_minimum_msat: 0,
3284 htlc_maximum_msat: 1_000_000_000,
3286 fee_proportional_millionths: 0,
3287 excess_data: Vec::new()
3291 // Now let's see if routing works if we know only htlc_maximum_msat.
3292 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3293 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3294 short_channel_id: 3,
3297 cltv_expiry_delta: 0,
3298 htlc_minimum_msat: 0,
3299 htlc_maximum_msat: 15_000,
3301 fee_proportional_millionths: 0,
3302 excess_data: Vec::new()
3306 // Attempt to route more than available results in a failure.
3307 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3308 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3309 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3310 } else { panic!(); }
3314 // Now, attempt to route an exact amount we have should be fine.
3315 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3316 assert_eq!(route.paths.len(), 1);
3317 let path = route.paths.last().unwrap();
3318 assert_eq!(path.len(), 2);
3319 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3320 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3323 // Now let's see if routing works if we know only capacity from the UTXO.
3325 // We can't change UTXO capacity on the fly, so we'll disable
3326 // the existing channel and add another one with the capacity we need.
3327 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3328 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3329 short_channel_id: 3,
3332 cltv_expiry_delta: 0,
3333 htlc_minimum_msat: 0,
3334 htlc_maximum_msat: MAX_VALUE_MSAT,
3336 fee_proportional_millionths: 0,
3337 excess_data: Vec::new()
3340 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3341 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3342 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3343 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3344 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3346 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3347 gossip_sync.add_chain_access(Some(chain_monitor));
3349 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3350 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3351 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3352 short_channel_id: 333,
3355 cltv_expiry_delta: (3 << 4) | 1,
3356 htlc_minimum_msat: 0,
3357 htlc_maximum_msat: 15_000,
3359 fee_proportional_millionths: 0,
3360 excess_data: Vec::new()
3362 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3363 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3364 short_channel_id: 333,
3367 cltv_expiry_delta: (3 << 4) | 2,
3368 htlc_minimum_msat: 0,
3369 htlc_maximum_msat: 15_000,
3371 fee_proportional_millionths: 0,
3372 excess_data: Vec::new()
3376 // Attempt to route more than available results in a failure.
3377 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3378 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3379 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3380 } else { panic!(); }
3384 // Now, attempt to route an exact amount we have should be fine.
3385 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3386 assert_eq!(route.paths.len(), 1);
3387 let path = route.paths.last().unwrap();
3388 assert_eq!(path.len(), 2);
3389 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3390 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3393 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3394 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3395 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3396 short_channel_id: 333,
3399 cltv_expiry_delta: 0,
3400 htlc_minimum_msat: 0,
3401 htlc_maximum_msat: 10_000,
3403 fee_proportional_millionths: 0,
3404 excess_data: Vec::new()
3408 // Attempt to route more than available results in a failure.
3409 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3410 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3411 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3412 } else { panic!(); }
3416 // Now, attempt to route an exact amount we have should be fine.
3417 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3418 assert_eq!(route.paths.len(), 1);
3419 let path = route.paths.last().unwrap();
3420 assert_eq!(path.len(), 2);
3421 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3422 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3427 fn available_liquidity_last_hop_test() {
3428 // Check that available liquidity properly limits the path even when only
3429 // one of the latter hops is limited.
3430 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3431 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3432 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3433 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3434 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3435 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3437 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3438 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3439 // Total capacity: 50 sats.
3441 // Disable other potential paths.
3442 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3443 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3444 short_channel_id: 2,
3447 cltv_expiry_delta: 0,
3448 htlc_minimum_msat: 0,
3449 htlc_maximum_msat: 100_000,
3451 fee_proportional_millionths: 0,
3452 excess_data: Vec::new()
3454 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3455 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3456 short_channel_id: 7,
3459 cltv_expiry_delta: 0,
3460 htlc_minimum_msat: 0,
3461 htlc_maximum_msat: 100_000,
3463 fee_proportional_millionths: 0,
3464 excess_data: Vec::new()
3469 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3471 short_channel_id: 12,
3474 cltv_expiry_delta: 0,
3475 htlc_minimum_msat: 0,
3476 htlc_maximum_msat: 100_000,
3478 fee_proportional_millionths: 0,
3479 excess_data: Vec::new()
3481 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3482 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3483 short_channel_id: 13,
3486 cltv_expiry_delta: 0,
3487 htlc_minimum_msat: 0,
3488 htlc_maximum_msat: 100_000,
3490 fee_proportional_millionths: 0,
3491 excess_data: Vec::new()
3494 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3495 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3496 short_channel_id: 6,
3499 cltv_expiry_delta: 0,
3500 htlc_minimum_msat: 0,
3501 htlc_maximum_msat: 50_000,
3503 fee_proportional_millionths: 0,
3504 excess_data: Vec::new()
3506 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3507 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3508 short_channel_id: 11,
3511 cltv_expiry_delta: 0,
3512 htlc_minimum_msat: 0,
3513 htlc_maximum_msat: 100_000,
3515 fee_proportional_millionths: 0,
3516 excess_data: Vec::new()
3519 // Attempt to route more than available results in a failure.
3520 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3521 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3522 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3523 } else { panic!(); }
3527 // Now, attempt to route 49 sats (just a bit below the capacity).
3528 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3529 assert_eq!(route.paths.len(), 1);
3530 let mut total_amount_paid_msat = 0;
3531 for path in &route.paths {
3532 assert_eq!(path.len(), 4);
3533 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3534 total_amount_paid_msat += path.last().unwrap().fee_msat;
3536 assert_eq!(total_amount_paid_msat, 49_000);
3540 // Attempt to route an exact amount is also fine
3541 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3542 assert_eq!(route.paths.len(), 1);
3543 let mut total_amount_paid_msat = 0;
3544 for path in &route.paths {
3545 assert_eq!(path.len(), 4);
3546 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3547 total_amount_paid_msat += path.last().unwrap().fee_msat;
3549 assert_eq!(total_amount_paid_msat, 50_000);
3554 fn ignore_fee_first_hop_test() {
3555 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3556 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3557 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3558 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3559 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3560 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3562 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3563 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3565 short_channel_id: 1,
3568 cltv_expiry_delta: 0,
3569 htlc_minimum_msat: 0,
3570 htlc_maximum_msat: 100_000,
3571 fee_base_msat: 1_000_000,
3572 fee_proportional_millionths: 0,
3573 excess_data: Vec::new()
3575 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3577 short_channel_id: 3,
3580 cltv_expiry_delta: 0,
3581 htlc_minimum_msat: 0,
3582 htlc_maximum_msat: 50_000,
3584 fee_proportional_millionths: 0,
3585 excess_data: Vec::new()
3589 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3590 assert_eq!(route.paths.len(), 1);
3591 let mut total_amount_paid_msat = 0;
3592 for path in &route.paths {
3593 assert_eq!(path.len(), 2);
3594 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3595 total_amount_paid_msat += path.last().unwrap().fee_msat;
3597 assert_eq!(total_amount_paid_msat, 50_000);
3602 fn simple_mpp_route_test() {
3603 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3604 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3605 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3606 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3607 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3608 let payment_params = PaymentParameters::from_node_id(nodes[2])
3609 .with_features(channelmanager::provided_invoice_features());
3611 // We need a route consisting of 3 paths:
3612 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3613 // To achieve this, the amount being transferred should be around
3614 // the total capacity of these 3 paths.
3616 // First, we set limits on these (previously unlimited) channels.
3617 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3619 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3620 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3621 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3622 short_channel_id: 1,
3625 cltv_expiry_delta: 0,
3626 htlc_minimum_msat: 0,
3627 htlc_maximum_msat: 100_000,
3629 fee_proportional_millionths: 0,
3630 excess_data: Vec::new()
3632 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3633 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3634 short_channel_id: 3,
3637 cltv_expiry_delta: 0,
3638 htlc_minimum_msat: 0,
3639 htlc_maximum_msat: 50_000,
3641 fee_proportional_millionths: 0,
3642 excess_data: Vec::new()
3645 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3646 // (total limit 60).
3647 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3648 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3649 short_channel_id: 12,
3652 cltv_expiry_delta: 0,
3653 htlc_minimum_msat: 0,
3654 htlc_maximum_msat: 60_000,
3656 fee_proportional_millionths: 0,
3657 excess_data: Vec::new()
3659 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3660 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3661 short_channel_id: 13,
3664 cltv_expiry_delta: 0,
3665 htlc_minimum_msat: 0,
3666 htlc_maximum_msat: 60_000,
3668 fee_proportional_millionths: 0,
3669 excess_data: Vec::new()
3672 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3673 // (total capacity 180 sats).
3674 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3675 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3676 short_channel_id: 2,
3679 cltv_expiry_delta: 0,
3680 htlc_minimum_msat: 0,
3681 htlc_maximum_msat: 200_000,
3683 fee_proportional_millionths: 0,
3684 excess_data: Vec::new()
3686 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3687 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3688 short_channel_id: 4,
3691 cltv_expiry_delta: 0,
3692 htlc_minimum_msat: 0,
3693 htlc_maximum_msat: 180_000,
3695 fee_proportional_millionths: 0,
3696 excess_data: Vec::new()
3700 // Attempt to route more than available results in a failure.
3701 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3702 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42,
3703 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3704 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3705 } else { panic!(); }
3709 // Attempt to route while setting max_path_count to 0 results in a failure.
3710 let zero_payment_params = payment_params.clone().with_max_path_count(0);
3711 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3712 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100, 42,
3713 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3714 assert_eq!(err, "Can't find a route with no paths allowed.");
3715 } else { panic!(); }
3719 // Attempt to route while setting max_path_count to 3 results in a failure.
3720 // This is the case because the minimal_value_contribution_msat would require each path
3721 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
3722 let fail_payment_params = payment_params.clone().with_max_path_count(3);
3723 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3724 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000, 42,
3725 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3726 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3727 } else { panic!(); }
3731 // Now, attempt to route 250 sats (just a bit below the capacity).
3732 // Our algorithm should provide us with these 3 paths.
3733 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3734 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3735 assert_eq!(route.paths.len(), 3);
3736 let mut total_amount_paid_msat = 0;
3737 for path in &route.paths {
3738 assert_eq!(path.len(), 2);
3739 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3740 total_amount_paid_msat += path.last().unwrap().fee_msat;
3742 assert_eq!(total_amount_paid_msat, 250_000);
3746 // Attempt to route an exact amount is also fine
3747 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3748 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3749 assert_eq!(route.paths.len(), 3);
3750 let mut total_amount_paid_msat = 0;
3751 for path in &route.paths {
3752 assert_eq!(path.len(), 2);
3753 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3754 total_amount_paid_msat += path.last().unwrap().fee_msat;
3756 assert_eq!(total_amount_paid_msat, 290_000);
3761 fn long_mpp_route_test() {
3762 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3763 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3764 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3765 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3766 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3767 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3769 // We need a route consisting of 3 paths:
3770 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3771 // Note that these paths overlap (channels 5, 12, 13).
3772 // We will route 300 sats.
3773 // Each path will have 100 sats capacity, those channels which
3774 // are used twice will have 200 sats capacity.
3776 // Disable other potential paths.
3777 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3778 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3779 short_channel_id: 2,
3782 cltv_expiry_delta: 0,
3783 htlc_minimum_msat: 0,
3784 htlc_maximum_msat: 100_000,
3786 fee_proportional_millionths: 0,
3787 excess_data: Vec::new()
3789 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3790 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3791 short_channel_id: 7,
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()
3802 // Path via {node0, node2} is channels {1, 3, 5}.
3803 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3804 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3805 short_channel_id: 1,
3808 cltv_expiry_delta: 0,
3809 htlc_minimum_msat: 0,
3810 htlc_maximum_msat: 100_000,
3812 fee_proportional_millionths: 0,
3813 excess_data: Vec::new()
3815 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3816 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3817 short_channel_id: 3,
3820 cltv_expiry_delta: 0,
3821 htlc_minimum_msat: 0,
3822 htlc_maximum_msat: 100_000,
3824 fee_proportional_millionths: 0,
3825 excess_data: Vec::new()
3828 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3829 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3830 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3831 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3832 short_channel_id: 5,
3835 cltv_expiry_delta: 0,
3836 htlc_minimum_msat: 0,
3837 htlc_maximum_msat: 200_000,
3839 fee_proportional_millionths: 0,
3840 excess_data: Vec::new()
3843 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3844 // Add 100 sats to the capacities of {12, 13}, because these channels
3845 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3846 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3848 short_channel_id: 12,
3851 cltv_expiry_delta: 0,
3852 htlc_minimum_msat: 0,
3853 htlc_maximum_msat: 200_000,
3855 fee_proportional_millionths: 0,
3856 excess_data: Vec::new()
3858 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3860 short_channel_id: 13,
3863 cltv_expiry_delta: 0,
3864 htlc_minimum_msat: 0,
3865 htlc_maximum_msat: 200_000,
3867 fee_proportional_millionths: 0,
3868 excess_data: Vec::new()
3871 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3872 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3873 short_channel_id: 6,
3876 cltv_expiry_delta: 0,
3877 htlc_minimum_msat: 0,
3878 htlc_maximum_msat: 100_000,
3880 fee_proportional_millionths: 0,
3881 excess_data: Vec::new()
3883 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3884 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3885 short_channel_id: 11,
3888 cltv_expiry_delta: 0,
3889 htlc_minimum_msat: 0,
3890 htlc_maximum_msat: 100_000,
3892 fee_proportional_millionths: 0,
3893 excess_data: Vec::new()
3896 // Path via {node7, node2} is channels {12, 13, 5}.
3897 // We already limited them to 200 sats (they are used twice for 100 sats).
3898 // Nothing to do here.
3901 // Attempt to route more than available results in a failure.
3902 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3903 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3904 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3905 } else { panic!(); }
3909 // Now, attempt to route 300 sats (exact amount we can route).
3910 // Our algorithm should provide us with these 3 paths, 100 sats each.
3911 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3912 assert_eq!(route.paths.len(), 3);
3914 let mut total_amount_paid_msat = 0;
3915 for path in &route.paths {
3916 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3917 total_amount_paid_msat += path.last().unwrap().fee_msat;
3919 assert_eq!(total_amount_paid_msat, 300_000);
3925 fn mpp_cheaper_route_test() {
3926 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3927 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3928 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3929 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3930 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3931 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3933 // This test checks that if we have two cheaper paths and one more expensive path,
3934 // so that liquidity-wise any 2 of 3 combination is sufficient,
3935 // two cheaper paths will be taken.
3936 // These paths have equal available liquidity.
3938 // We need a combination of 3 paths:
3939 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3940 // Note that these paths overlap (channels 5, 12, 13).
3941 // Each path will have 100 sats capacity, those channels which
3942 // are used twice will have 200 sats capacity.
3944 // Disable other potential paths.
3945 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3946 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3947 short_channel_id: 2,
3950 cltv_expiry_delta: 0,
3951 htlc_minimum_msat: 0,
3952 htlc_maximum_msat: 100_000,
3954 fee_proportional_millionths: 0,
3955 excess_data: Vec::new()
3957 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3958 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3959 short_channel_id: 7,
3962 cltv_expiry_delta: 0,
3963 htlc_minimum_msat: 0,
3964 htlc_maximum_msat: 100_000,
3966 fee_proportional_millionths: 0,
3967 excess_data: Vec::new()
3970 // Path via {node0, node2} is channels {1, 3, 5}.
3971 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3972 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3973 short_channel_id: 1,
3976 cltv_expiry_delta: 0,
3977 htlc_minimum_msat: 0,
3978 htlc_maximum_msat: 100_000,
3980 fee_proportional_millionths: 0,
3981 excess_data: Vec::new()
3983 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3984 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3985 short_channel_id: 3,
3988 cltv_expiry_delta: 0,
3989 htlc_minimum_msat: 0,
3990 htlc_maximum_msat: 100_000,
3992 fee_proportional_millionths: 0,
3993 excess_data: Vec::new()
3996 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3997 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3998 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3999 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4000 short_channel_id: 5,
4003 cltv_expiry_delta: 0,
4004 htlc_minimum_msat: 0,
4005 htlc_maximum_msat: 200_000,
4007 fee_proportional_millionths: 0,
4008 excess_data: Vec::new()
4011 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4012 // Add 100 sats to the capacities of {12, 13}, because these channels
4013 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4014 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4015 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4016 short_channel_id: 12,
4019 cltv_expiry_delta: 0,
4020 htlc_minimum_msat: 0,
4021 htlc_maximum_msat: 200_000,
4023 fee_proportional_millionths: 0,
4024 excess_data: Vec::new()
4026 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4027 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4028 short_channel_id: 13,
4031 cltv_expiry_delta: 0,
4032 htlc_minimum_msat: 0,
4033 htlc_maximum_msat: 200_000,
4035 fee_proportional_millionths: 0,
4036 excess_data: Vec::new()
4039 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4040 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4041 short_channel_id: 6,
4044 cltv_expiry_delta: 0,
4045 htlc_minimum_msat: 0,
4046 htlc_maximum_msat: 100_000,
4047 fee_base_msat: 1_000,
4048 fee_proportional_millionths: 0,
4049 excess_data: Vec::new()
4051 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4052 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4053 short_channel_id: 11,
4056 cltv_expiry_delta: 0,
4057 htlc_minimum_msat: 0,
4058 htlc_maximum_msat: 100_000,
4060 fee_proportional_millionths: 0,
4061 excess_data: Vec::new()
4064 // Path via {node7, node2} is channels {12, 13, 5}.
4065 // We already limited them to 200 sats (they are used twice for 100 sats).
4066 // Nothing to do here.
4069 // Now, attempt to route 180 sats.
4070 // Our algorithm should provide us with these 2 paths.
4071 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4072 assert_eq!(route.paths.len(), 2);
4074 let mut total_value_transferred_msat = 0;
4075 let mut total_paid_msat = 0;
4076 for path in &route.paths {
4077 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4078 total_value_transferred_msat += path.last().unwrap().fee_msat;
4080 total_paid_msat += hop.fee_msat;
4083 // If we paid fee, this would be higher.
4084 assert_eq!(total_value_transferred_msat, 180_000);
4085 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4086 assert_eq!(total_fees_paid, 0);
4091 fn fees_on_mpp_route_test() {
4092 // This test makes sure that MPP algorithm properly takes into account
4093 // fees charged on the channels, by making the fees impactful:
4094 // if the fee is not properly accounted for, the behavior is different.
4095 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4096 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4097 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4098 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4099 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4100 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4102 // We need a route consisting of 2 paths:
4103 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4104 // We will route 200 sats, Each path will have 100 sats capacity.
4106 // This test is not particularly stable: e.g.,
4107 // there's a way to route via {node0, node2, node4}.
4108 // It works while pathfinding is deterministic, but can be broken otherwise.
4109 // It's fine to ignore this concern for now.
4111 // Disable other potential paths.
4112 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4113 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4114 short_channel_id: 2,
4117 cltv_expiry_delta: 0,
4118 htlc_minimum_msat: 0,
4119 htlc_maximum_msat: 100_000,
4121 fee_proportional_millionths: 0,
4122 excess_data: Vec::new()
4125 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4126 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4127 short_channel_id: 7,
4130 cltv_expiry_delta: 0,
4131 htlc_minimum_msat: 0,
4132 htlc_maximum_msat: 100_000,
4134 fee_proportional_millionths: 0,
4135 excess_data: Vec::new()
4138 // Path via {node0, node2} is channels {1, 3, 5}.
4139 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4140 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4141 short_channel_id: 1,
4144 cltv_expiry_delta: 0,
4145 htlc_minimum_msat: 0,
4146 htlc_maximum_msat: 100_000,
4148 fee_proportional_millionths: 0,
4149 excess_data: Vec::new()
4151 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4152 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4153 short_channel_id: 3,
4156 cltv_expiry_delta: 0,
4157 htlc_minimum_msat: 0,
4158 htlc_maximum_msat: 100_000,
4160 fee_proportional_millionths: 0,
4161 excess_data: Vec::new()
4164 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4165 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4166 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4167 short_channel_id: 5,
4170 cltv_expiry_delta: 0,
4171 htlc_minimum_msat: 0,
4172 htlc_maximum_msat: 100_000,
4174 fee_proportional_millionths: 0,
4175 excess_data: Vec::new()
4178 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4179 // All channels should be 100 sats capacity. But for the fee experiment,
4180 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4181 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4182 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4183 // so no matter how large are other channels,
4184 // the whole path will be limited by 100 sats with just these 2 conditions:
4185 // - channel 12 capacity is 250 sats
4186 // - fee for channel 6 is 150 sats
4187 // Let's test this by enforcing these 2 conditions and removing other limits.
4188 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4189 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4190 short_channel_id: 12,
4193 cltv_expiry_delta: 0,
4194 htlc_minimum_msat: 0,
4195 htlc_maximum_msat: 250_000,
4197 fee_proportional_millionths: 0,
4198 excess_data: Vec::new()
4200 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4201 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4202 short_channel_id: 13,
4205 cltv_expiry_delta: 0,
4206 htlc_minimum_msat: 0,
4207 htlc_maximum_msat: MAX_VALUE_MSAT,
4209 fee_proportional_millionths: 0,
4210 excess_data: Vec::new()
4213 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4214 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4215 short_channel_id: 6,
4218 cltv_expiry_delta: 0,
4219 htlc_minimum_msat: 0,
4220 htlc_maximum_msat: MAX_VALUE_MSAT,
4221 fee_base_msat: 150_000,
4222 fee_proportional_millionths: 0,
4223 excess_data: Vec::new()
4225 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4226 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4227 short_channel_id: 11,
4230 cltv_expiry_delta: 0,
4231 htlc_minimum_msat: 0,
4232 htlc_maximum_msat: MAX_VALUE_MSAT,
4234 fee_proportional_millionths: 0,
4235 excess_data: Vec::new()
4239 // Attempt to route more than available results in a failure.
4240 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4241 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4242 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4243 } else { panic!(); }
4247 // Now, attempt to route 200 sats (exact amount we can route).
4248 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4249 assert_eq!(route.paths.len(), 2);
4251 let mut total_amount_paid_msat = 0;
4252 for path in &route.paths {
4253 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4254 total_amount_paid_msat += path.last().unwrap().fee_msat;
4256 assert_eq!(total_amount_paid_msat, 200_000);
4257 assert_eq!(route.get_total_fees(), 150_000);
4262 fn mpp_with_last_hops() {
4263 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4264 // via a single last-hop route hint, we'd fail to route if we first collected routes
4265 // totaling close but not quite enough to fund the full payment.
4267 // This was because we considered last-hop hints to have exactly the sought payment amount
4268 // instead of the amount we were trying to collect, needlessly limiting our path searching
4269 // at the very first hop.
4271 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4272 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4273 // to only have the remaining to-collect amount in available liquidity.
4275 // This bug appeared in production in some specific channel configurations.
4276 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4277 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4278 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4279 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4280 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4281 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(channelmanager::provided_invoice_features())
4282 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4283 src_node_id: nodes[2],
4284 short_channel_id: 42,
4285 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4286 cltv_expiry_delta: 42,
4287 htlc_minimum_msat: None,
4288 htlc_maximum_msat: None,
4289 }])]).with_max_channel_saturation_power_of_half(0);
4291 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4292 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4293 // would first use the no-fee route and then fail to find a path along the second route as
4294 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4295 // under 5% of our payment amount.
4296 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4297 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4298 short_channel_id: 1,
4301 cltv_expiry_delta: (5 << 4) | 5,
4302 htlc_minimum_msat: 0,
4303 htlc_maximum_msat: 99_000,
4304 fee_base_msat: u32::max_value(),
4305 fee_proportional_millionths: u32::max_value(),
4306 excess_data: Vec::new()
4308 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4309 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4310 short_channel_id: 2,
4313 cltv_expiry_delta: (5 << 4) | 3,
4314 htlc_minimum_msat: 0,
4315 htlc_maximum_msat: 99_000,
4316 fee_base_msat: u32::max_value(),
4317 fee_proportional_millionths: u32::max_value(),
4318 excess_data: Vec::new()
4320 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4321 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4322 short_channel_id: 4,
4325 cltv_expiry_delta: (4 << 4) | 1,
4326 htlc_minimum_msat: 0,
4327 htlc_maximum_msat: MAX_VALUE_MSAT,
4329 fee_proportional_millionths: 0,
4330 excess_data: Vec::new()
4332 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4333 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4334 short_channel_id: 13,
4336 flags: 0|2, // Channel disabled
4337 cltv_expiry_delta: (13 << 4) | 1,
4338 htlc_minimum_msat: 0,
4339 htlc_maximum_msat: MAX_VALUE_MSAT,
4341 fee_proportional_millionths: 2000000,
4342 excess_data: Vec::new()
4345 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4347 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();
4348 assert_eq!(route.paths.len(), 2);
4349 route.paths.sort_by_key(|path| path[0].short_channel_id);
4350 // Paths are manually ordered ordered by SCID, so:
4351 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4352 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4353 assert_eq!(route.paths[0][0].short_channel_id, 1);
4354 assert_eq!(route.paths[0][0].fee_msat, 0);
4355 assert_eq!(route.paths[0][2].fee_msat, 99_000);
4356 assert_eq!(route.paths[1][0].short_channel_id, 2);
4357 assert_eq!(route.paths[1][0].fee_msat, 1);
4358 assert_eq!(route.paths[1][2].fee_msat, 1_000);
4359 assert_eq!(route.get_total_fees(), 1);
4360 assert_eq!(route.get_total_amount(), 100_000);
4364 fn drop_lowest_channel_mpp_route_test() {
4365 // This test checks that low-capacity channel is dropped when after
4366 // path finding we realize that we found more capacity than we need.
4367 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4368 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4369 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4370 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4371 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4372 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features())
4373 .with_max_channel_saturation_power_of_half(0);
4375 // We need a route consisting of 3 paths:
4376 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4378 // The first and the second paths should be sufficient, but the third should be
4379 // cheaper, so that we select it but drop later.
4381 // First, we set limits on these (previously unlimited) channels.
4382 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4384 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4385 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4386 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4387 short_channel_id: 1,
4390 cltv_expiry_delta: 0,
4391 htlc_minimum_msat: 0,
4392 htlc_maximum_msat: 100_000,
4394 fee_proportional_millionths: 0,
4395 excess_data: Vec::new()
4397 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4398 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4399 short_channel_id: 3,
4402 cltv_expiry_delta: 0,
4403 htlc_minimum_msat: 0,
4404 htlc_maximum_msat: 50_000,
4406 fee_proportional_millionths: 0,
4407 excess_data: Vec::new()
4410 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4411 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4412 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4413 short_channel_id: 12,
4416 cltv_expiry_delta: 0,
4417 htlc_minimum_msat: 0,
4418 htlc_maximum_msat: 60_000,
4420 fee_proportional_millionths: 0,
4421 excess_data: Vec::new()
4423 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4424 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4425 short_channel_id: 13,
4428 cltv_expiry_delta: 0,
4429 htlc_minimum_msat: 0,
4430 htlc_maximum_msat: 60_000,
4432 fee_proportional_millionths: 0,
4433 excess_data: Vec::new()
4436 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4437 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4438 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4439 short_channel_id: 2,
4442 cltv_expiry_delta: 0,
4443 htlc_minimum_msat: 0,
4444 htlc_maximum_msat: 20_000,
4446 fee_proportional_millionths: 0,
4447 excess_data: Vec::new()
4449 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4450 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4451 short_channel_id: 4,
4454 cltv_expiry_delta: 0,
4455 htlc_minimum_msat: 0,
4456 htlc_maximum_msat: 20_000,
4458 fee_proportional_millionths: 0,
4459 excess_data: Vec::new()
4463 // Attempt to route more than available results in a failure.
4464 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4465 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4466 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4467 } else { panic!(); }
4471 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4472 // Our algorithm should provide us with these 3 paths.
4473 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4474 assert_eq!(route.paths.len(), 3);
4475 let mut total_amount_paid_msat = 0;
4476 for path in &route.paths {
4477 assert_eq!(path.len(), 2);
4478 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4479 total_amount_paid_msat += path.last().unwrap().fee_msat;
4481 assert_eq!(total_amount_paid_msat, 125_000);
4485 // Attempt to route without the last small cheap channel
4486 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4487 assert_eq!(route.paths.len(), 2);
4488 let mut total_amount_paid_msat = 0;
4489 for path in &route.paths {
4490 assert_eq!(path.len(), 2);
4491 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4492 total_amount_paid_msat += path.last().unwrap().fee_msat;
4494 assert_eq!(total_amount_paid_msat, 90_000);
4499 fn min_criteria_consistency() {
4500 // Test that we don't use an inconsistent metric between updating and walking nodes during
4501 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4502 // was updated with a different criterion from the heap sorting, resulting in loops in
4503 // calculated paths. We test for that specific case here.
4505 // We construct a network that looks like this:
4507 // node2 -1(3)2- node3
4511 // node1 -1(5)2- node4 -1(1)2- node6
4517 // We create a loop on the side of our real path - our destination is node 6, with a
4518 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4519 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4520 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4521 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4522 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4523 // "previous hop" being set to node 3, creating a loop in the path.
4524 let secp_ctx = Secp256k1::new();
4525 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4526 let logger = Arc::new(ln_test_utils::TestLogger::new());
4527 let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
4528 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
4529 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4530 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4531 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4532 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4533 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4535 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4536 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4537 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4538 short_channel_id: 6,
4541 cltv_expiry_delta: (6 << 4) | 0,
4542 htlc_minimum_msat: 0,
4543 htlc_maximum_msat: MAX_VALUE_MSAT,
4545 fee_proportional_millionths: 0,
4546 excess_data: Vec::new()
4548 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4550 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4551 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4552 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4553 short_channel_id: 5,
4556 cltv_expiry_delta: (5 << 4) | 0,
4557 htlc_minimum_msat: 0,
4558 htlc_maximum_msat: MAX_VALUE_MSAT,
4560 fee_proportional_millionths: 0,
4561 excess_data: Vec::new()
4563 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4565 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4566 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4567 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4568 short_channel_id: 4,
4571 cltv_expiry_delta: (4 << 4) | 0,
4572 htlc_minimum_msat: 0,
4573 htlc_maximum_msat: MAX_VALUE_MSAT,
4575 fee_proportional_millionths: 0,
4576 excess_data: Vec::new()
4578 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4580 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4581 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4582 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4583 short_channel_id: 3,
4586 cltv_expiry_delta: (3 << 4) | 0,
4587 htlc_minimum_msat: 0,
4588 htlc_maximum_msat: MAX_VALUE_MSAT,
4590 fee_proportional_millionths: 0,
4591 excess_data: Vec::new()
4593 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4595 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4596 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4598 short_channel_id: 2,
4601 cltv_expiry_delta: (2 << 4) | 0,
4602 htlc_minimum_msat: 0,
4603 htlc_maximum_msat: MAX_VALUE_MSAT,
4605 fee_proportional_millionths: 0,
4606 excess_data: Vec::new()
4609 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4610 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4611 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4612 short_channel_id: 1,
4615 cltv_expiry_delta: (1 << 4) | 0,
4616 htlc_minimum_msat: 100,
4617 htlc_maximum_msat: MAX_VALUE_MSAT,
4619 fee_proportional_millionths: 0,
4620 excess_data: Vec::new()
4622 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4625 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4626 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4627 assert_eq!(route.paths.len(), 1);
4628 assert_eq!(route.paths[0].len(), 3);
4630 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4631 assert_eq!(route.paths[0][0].short_channel_id, 6);
4632 assert_eq!(route.paths[0][0].fee_msat, 100);
4633 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4634 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4635 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4637 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4638 assert_eq!(route.paths[0][1].short_channel_id, 5);
4639 assert_eq!(route.paths[0][1].fee_msat, 0);
4640 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4641 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4642 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4644 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4645 assert_eq!(route.paths[0][2].short_channel_id, 1);
4646 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4647 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4648 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4649 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4655 fn exact_fee_liquidity_limit() {
4656 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4657 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4658 // we calculated fees on a higher value, resulting in us ignoring such paths.
4659 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4660 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4661 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4662 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4663 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4664 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4666 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4668 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4669 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4670 short_channel_id: 2,
4673 cltv_expiry_delta: 0,
4674 htlc_minimum_msat: 0,
4675 htlc_maximum_msat: 85_000,
4677 fee_proportional_millionths: 0,
4678 excess_data: Vec::new()
4681 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4682 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4683 short_channel_id: 12,
4686 cltv_expiry_delta: (4 << 4) | 1,
4687 htlc_minimum_msat: 0,
4688 htlc_maximum_msat: 270_000,
4690 fee_proportional_millionths: 1000000,
4691 excess_data: Vec::new()
4695 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4696 // 200% fee charged channel 13 in the 1-to-2 direction.
4697 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4698 assert_eq!(route.paths.len(), 1);
4699 assert_eq!(route.paths[0].len(), 2);
4701 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4702 assert_eq!(route.paths[0][0].short_channel_id, 12);
4703 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4704 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4705 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4706 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4708 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4709 assert_eq!(route.paths[0][1].short_channel_id, 13);
4710 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4711 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4712 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4713 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4718 fn htlc_max_reduction_below_min() {
4719 // Test that if, while walking the graph, we reduce the value being sent to meet an
4720 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4721 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4722 // resulting in us thinking there is no possible path, even if other paths exist.
4723 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4724 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4725 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4726 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4727 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4728 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
4730 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4731 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4732 // then try to send 90_000.
4733 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4734 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4735 short_channel_id: 2,
4738 cltv_expiry_delta: 0,
4739 htlc_minimum_msat: 0,
4740 htlc_maximum_msat: 80_000,
4742 fee_proportional_millionths: 0,
4743 excess_data: Vec::new()
4745 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4746 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4747 short_channel_id: 4,
4750 cltv_expiry_delta: (4 << 4) | 1,
4751 htlc_minimum_msat: 90_000,
4752 htlc_maximum_msat: MAX_VALUE_MSAT,
4754 fee_proportional_millionths: 0,
4755 excess_data: Vec::new()
4759 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4760 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4761 // expensive) channels 12-13 path.
4762 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4763 assert_eq!(route.paths.len(), 1);
4764 assert_eq!(route.paths[0].len(), 2);
4766 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4767 assert_eq!(route.paths[0][0].short_channel_id, 12);
4768 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4769 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4770 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4771 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4773 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4774 assert_eq!(route.paths[0][1].short_channel_id, 13);
4775 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4776 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4777 assert_eq!(route.paths[0][1].node_features.le_flags(), channelmanager::provided_invoice_features().le_flags());
4778 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4783 fn multiple_direct_first_hops() {
4784 // Previously we'd only ever considered one first hop path per counterparty.
4785 // However, as we don't restrict users to one channel per peer, we really need to support
4786 // looking at all first hop paths.
4787 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4788 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4789 // route over multiple channels with the same first hop.
4790 let secp_ctx = Secp256k1::new();
4791 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4792 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4793 let logger = Arc::new(ln_test_utils::TestLogger::new());
4794 let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
4795 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4796 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(channelmanager::provided_invoice_features());
4797 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4798 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4801 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4802 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 200_000),
4803 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 10_000),
4804 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4805 assert_eq!(route.paths.len(), 1);
4806 assert_eq!(route.paths[0].len(), 1);
4808 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4809 assert_eq!(route.paths[0][0].short_channel_id, 3);
4810 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4813 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4814 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
4815 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
4816 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4817 assert_eq!(route.paths.len(), 2);
4818 assert_eq!(route.paths[0].len(), 1);
4819 assert_eq!(route.paths[1].len(), 1);
4821 assert!((route.paths[0][0].short_channel_id == 3 && route.paths[1][0].short_channel_id == 2) ||
4822 (route.paths[0][0].short_channel_id == 2 && route.paths[1][0].short_channel_id == 3));
4824 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4825 assert_eq!(route.paths[0][0].fee_msat, 50_000);
4827 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
4828 assert_eq!(route.paths[1][0].fee_msat, 50_000);
4832 // If we have a bunch of outbound channels to the same node, where most are not
4833 // sufficient to pay the full payment, but one is, we should default to just using the
4834 // one single channel that has sufficient balance, avoiding MPP.
4836 // If we have several options above the 3xpayment value threshold, we should pick the
4837 // smallest of them, avoiding further fragmenting our available outbound balance to
4839 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4840 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
4841 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
4842 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(), 50_000),
4843 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(), 300_000),
4844 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(), 50_000),
4845 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(), 50_000),
4846 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(), 50_000),
4847 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(), 1_000_000),
4848 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4849 assert_eq!(route.paths.len(), 1);
4850 assert_eq!(route.paths[0].len(), 1);
4852 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4853 assert_eq!(route.paths[0][0].short_channel_id, 6);
4854 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4859 fn prefers_shorter_route_with_higher_fees() {
4860 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4861 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4862 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4864 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
4865 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4866 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4867 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4868 let route = get_route(
4869 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
4870 Arc::clone(&logger), &scorer, &random_seed_bytes
4872 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4874 assert_eq!(route.get_total_fees(), 100);
4875 assert_eq!(route.get_total_amount(), 100);
4876 assert_eq!(path, vec![2, 4, 6, 11, 8]);
4878 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
4879 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
4880 let scorer = ln_test_utils::TestScorer::with_penalty(100);
4881 let route = get_route(
4882 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
4883 Arc::clone(&logger), &scorer, &random_seed_bytes
4885 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4887 assert_eq!(route.get_total_fees(), 300);
4888 assert_eq!(route.get_total_amount(), 100);
4889 assert_eq!(path, vec![2, 4, 7, 10]);
4892 struct BadChannelScorer {
4893 short_channel_id: u64,
4897 impl Writeable for BadChannelScorer {
4898 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
4900 impl Score for BadChannelScorer {
4901 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage) -> u64 {
4902 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
4905 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4906 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
4907 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4908 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
4911 struct BadNodeScorer {
4916 impl Writeable for BadNodeScorer {
4917 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
4920 impl Score for BadNodeScorer {
4921 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage) -> u64 {
4922 if *target == self.node_id { u64::max_value() } else { 0 }
4925 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4926 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
4927 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4928 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
4932 fn avoids_routing_through_bad_channels_and_nodes() {
4933 let (secp_ctx, network, _, _, logger) = build_graph();
4934 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4935 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4936 let network_graph = network.read_only();
4938 // A path to nodes[6] exists when no penalties are applied to any channel.
4939 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4940 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4941 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4942 let route = get_route(
4943 &our_id, &payment_params, &network_graph, None, 100, 42,
4944 Arc::clone(&logger), &scorer, &random_seed_bytes
4946 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4948 assert_eq!(route.get_total_fees(), 100);
4949 assert_eq!(route.get_total_amount(), 100);
4950 assert_eq!(path, vec![2, 4, 6, 11, 8]);
4952 // A different path to nodes[6] exists if channel 6 cannot be routed over.
4953 let scorer = BadChannelScorer { short_channel_id: 6 };
4954 let route = get_route(
4955 &our_id, &payment_params, &network_graph, None, 100, 42,
4956 Arc::clone(&logger), &scorer, &random_seed_bytes
4958 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4960 assert_eq!(route.get_total_fees(), 300);
4961 assert_eq!(route.get_total_amount(), 100);
4962 assert_eq!(path, vec![2, 4, 7, 10]);
4964 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
4965 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
4967 &our_id, &payment_params, &network_graph, None, 100, 42,
4968 Arc::clone(&logger), &scorer, &random_seed_bytes
4970 Err(LightningError { err, .. } ) => {
4971 assert_eq!(err, "Failed to find a path to the given destination");
4973 Ok(_) => panic!("Expected error"),
4978 fn total_fees_single_path() {
4982 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
4983 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4984 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
4987 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
4988 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4989 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
4992 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
4993 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4994 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
4997 payment_params: None,
5000 assert_eq!(route.get_total_fees(), 250);
5001 assert_eq!(route.get_total_amount(), 225);
5005 fn total_fees_multi_path() {
5009 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5010 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5011 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5014 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5015 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5016 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5020 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5021 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5022 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5025 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5026 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5027 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5030 payment_params: None,
5033 assert_eq!(route.get_total_fees(), 200);
5034 assert_eq!(route.get_total_amount(), 300);
5038 fn total_empty_route_no_panic() {
5039 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5040 // would both panic if the route was completely empty. We test to ensure they return 0
5041 // here, even though its somewhat nonsensical as a route.
5042 let route = Route { paths: Vec::new(), payment_params: None };
5044 assert_eq!(route.get_total_fees(), 0);
5045 assert_eq!(route.get_total_amount(), 0);
5049 fn limits_total_cltv_delta() {
5050 let (secp_ctx, network, _, _, logger) = build_graph();
5051 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5052 let network_graph = network.read_only();
5054 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5056 // Make sure that generally there is at least one route available
5057 let feasible_max_total_cltv_delta = 1008;
5058 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5059 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5060 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5061 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5062 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5063 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5064 assert_ne!(path.len(), 0);
5066 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5067 let fail_max_total_cltv_delta = 23;
5068 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5069 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5070 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5072 Err(LightningError { err, .. } ) => {
5073 assert_eq!(err, "Failed to find a path to the given destination");
5075 Ok(_) => panic!("Expected error"),
5080 fn avoids_recently_failed_paths() {
5081 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5082 // randomly inserting channels into it until we can't find a route anymore.
5083 let (secp_ctx, network, _, _, logger) = build_graph();
5084 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5085 let network_graph = network.read_only();
5087 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5088 let mut payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5089 .with_max_path_count(1);
5090 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5091 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5093 // We should be able to find a route initially, and then after we fail a few random
5094 // channels eventually we won't be able to any longer.
5095 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).is_ok());
5097 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes) {
5098 for chan in route.paths[0].iter() {
5099 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5101 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5102 % route.paths[0].len();
5103 payment_params.previously_failed_channels.push(route.paths[0][victim].short_channel_id);
5109 fn limits_path_length() {
5110 let (secp_ctx, network, _, _, logger) = build_line_graph();
5111 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5112 let network_graph = network.read_only();
5114 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5115 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5116 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5118 // First check we can actually create a long route on this graph.
5119 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5120 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5121 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5122 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5123 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5125 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5126 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5127 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5128 Arc::clone(&logger), &scorer, &random_seed_bytes)
5130 Err(LightningError { err, .. } ) => {
5131 assert_eq!(err, "Failed to find a path to the given destination");
5133 Ok(_) => panic!("Expected error"),
5138 fn adds_and_limits_cltv_offset() {
5139 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5140 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5142 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5144 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5145 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5146 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5147 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5148 assert_eq!(route.paths.len(), 1);
5150 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5152 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5153 let mut route_default = route.clone();
5154 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5155 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5156 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5157 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5158 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5160 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5161 let mut route_limited = route.clone();
5162 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5163 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5164 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5165 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5166 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5170 fn adds_plausible_cltv_offset() {
5171 let (secp_ctx, network, _, _, logger) = build_graph();
5172 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5173 let network_graph = network.read_only();
5174 let network_nodes = network_graph.nodes();
5175 let network_channels = network_graph.channels();
5176 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5177 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5178 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5179 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5181 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5182 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5183 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5185 let mut path_plausibility = vec![];
5187 for p in route.paths {
5188 // 1. Select random observation point
5189 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5190 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5192 prng.process_in_place(&mut random_bytes);
5193 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5194 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5196 // 2. Calculate what CLTV expiry delta we would observe there
5197 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5199 // 3. Starting from the observation point, find candidate paths
5200 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5201 candidates.push_back((observation_point, vec![]));
5203 let mut found_plausible_candidate = false;
5205 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5206 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5207 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5208 found_plausible_candidate = true;
5209 break 'candidate_loop;
5213 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5214 for channel_id in &cur_node.channels {
5215 if let Some(channel_info) = network_channels.get(&channel_id) {
5216 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5217 if let Some(channel_update_info) = dir_info.direction() {
5218 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5219 if cur_path_cltv_deltas.iter().sum::<u32>()
5220 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5221 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5222 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5223 candidates.push_back((*next_id, new_path_cltv_deltas));
5232 path_plausibility.push(found_plausible_candidate);
5234 assert!(path_plausibility.iter().all(|x| *x));
5238 fn builds_correct_path_from_hops() {
5239 let (secp_ctx, network, _, _, logger) = build_graph();
5240 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5241 let network_graph = network.read_only();
5243 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5244 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5246 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5247 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5248 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5249 &network_graph, 100, 0, Arc::clone(&logger), &random_seed_bytes).unwrap();
5250 let route_hop_pubkeys = route.paths[0].iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5251 assert_eq!(hops.len(), route.paths[0].len());
5252 for (idx, hop_pubkey) in hops.iter().enumerate() {
5253 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5258 fn avoids_saturating_channels() {
5259 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5260 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5262 let scorer = ProbabilisticScorer::new(Default::default(), &*network_graph, Arc::clone(&logger));
5264 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5265 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5266 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5267 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5268 short_channel_id: 4,
5271 cltv_expiry_delta: (4 << 4) | 1,
5272 htlc_minimum_msat: 0,
5273 htlc_maximum_msat: 250_000_000,
5275 fee_proportional_millionths: 0,
5276 excess_data: Vec::new()
5278 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5279 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5280 short_channel_id: 13,
5283 cltv_expiry_delta: (13 << 4) | 1,
5284 htlc_minimum_msat: 0,
5285 htlc_maximum_msat: 250_000_000,
5287 fee_proportional_millionths: 0,
5288 excess_data: Vec::new()
5291 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
5292 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5293 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5294 // 100,000 sats is less than the available liquidity on each channel, set above.
5295 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();
5296 assert_eq!(route.paths.len(), 2);
5297 assert!((route.paths[0][1].short_channel_id == 4 && route.paths[1][1].short_channel_id == 13) ||
5298 (route.paths[1][1].short_channel_id == 4 && route.paths[0][1].short_channel_id == 13));
5301 #[cfg(not(feature = "no-std"))]
5302 pub(super) fn random_init_seed() -> u64 {
5303 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5304 use core::hash::{BuildHasher, Hasher};
5305 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5306 println!("Using seed of {}", seed);
5309 #[cfg(not(feature = "no-std"))]
5310 use crate::util::ser::ReadableArgs;
5313 #[cfg(not(feature = "no-std"))]
5314 fn generate_routes() {
5315 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5317 let mut d = match super::bench_utils::get_route_file() {
5324 let logger = ln_test_utils::TestLogger::new();
5325 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5326 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5327 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5329 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5330 let mut seed = random_init_seed() as usize;
5331 let nodes = graph.read_only().nodes().clone();
5332 'load_endpoints: for _ in 0..10 {
5334 seed = seed.overflowing_mul(0xdeadbeef).0;
5335 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5336 seed = seed.overflowing_mul(0xdeadbeef).0;
5337 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5338 let payment_params = PaymentParameters::from_node_id(dst);
5339 let amt = seed as u64 % 200_000_000;
5340 let params = ProbabilisticScoringParameters::default();
5341 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5342 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5343 continue 'load_endpoints;
5350 #[cfg(not(feature = "no-std"))]
5351 fn generate_routes_mpp() {
5352 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5354 let mut d = match super::bench_utils::get_route_file() {
5361 let logger = ln_test_utils::TestLogger::new();
5362 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5363 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5364 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5366 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5367 let mut seed = random_init_seed() as usize;
5368 let nodes = graph.read_only().nodes().clone();
5369 'load_endpoints: for _ in 0..10 {
5371 seed = seed.overflowing_mul(0xdeadbeef).0;
5372 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5373 seed = seed.overflowing_mul(0xdeadbeef).0;
5374 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5375 let payment_params = PaymentParameters::from_node_id(dst).with_features(channelmanager::provided_invoice_features());
5376 let amt = seed as u64 % 200_000_000;
5377 let params = ProbabilisticScoringParameters::default();
5378 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5379 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5380 continue 'load_endpoints;
5387 fn honors_manual_penalties() {
5388 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5389 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5391 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5392 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5394 let scorer_params = ProbabilisticScoringParameters::default();
5395 let mut scorer = ProbabilisticScorer::new(scorer_params, Arc::clone(&network_graph), Arc::clone(&logger));
5397 // First check set manual penalties are returned by the scorer.
5398 let usage = ChannelUsage {
5400 inflight_htlc_msat: 0,
5401 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
5403 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5404 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5405 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage), 456);
5407 // Then check we can get a normal route
5408 let payment_params = PaymentParameters::from_node_id(nodes[10]);
5409 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5410 assert!(route.is_ok());
5412 // Then check that we can't get a route if we ban an intermediate node.
5413 scorer.add_banned(&NodeId::from_pubkey(&nodes[3]));
5414 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5415 assert!(route.is_err());
5417 // Finally make sure we can route again, when we remove the ban.
5418 scorer.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5419 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5420 assert!(route.is_ok());
5424 #[cfg(all(test, not(feature = "no-std")))]
5425 pub(crate) mod bench_utils {
5427 /// Tries to open a network graph file, or panics with a URL to fetch it.
5428 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5429 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5430 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5431 .or_else(|_| { // Fall back to guessing based on the binary location
5432 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5433 let mut path = std::env::current_exe().unwrap();
5434 path.pop(); // lightning-...
5436 path.pop(); // debug
5437 path.pop(); // target
5438 path.push("lightning");
5439 path.push("net_graph-2021-05-31.bin");
5440 eprintln!("{}", path.to_str().unwrap());
5443 .map_err(|_| "Please fetch https://bitcoin.ninja/ldk-net_graph-v0.0.15-2021-05-31.bin and place it at lightning/net_graph-2021-05-31.bin");
5444 #[cfg(require_route_graph_test)]
5445 return Ok(res.unwrap());
5446 #[cfg(not(require_route_graph_test))]
5451 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5454 use bitcoin::hashes::Hash;
5455 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5456 use crate::chain::transaction::OutPoint;
5457 use crate::chain::keysinterface::{KeysManager,KeysInterface};
5458 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
5459 use crate::ln::features::InvoiceFeatures;
5460 use crate::routing::gossip::NetworkGraph;
5461 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
5462 use crate::util::logger::{Logger, Record};
5463 use crate::util::ser::ReadableArgs;
5467 struct DummyLogger {}
5468 impl Logger for DummyLogger {
5469 fn log(&self, _record: &Record) {}
5472 fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
5473 let mut d = bench_utils::get_route_file().unwrap();
5474 NetworkGraph::read(&mut d, logger).unwrap()
5477 fn payer_pubkey() -> PublicKey {
5478 let secp_ctx = Secp256k1::new();
5479 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5483 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5485 channel_id: [0; 32],
5486 counterparty: ChannelCounterparty {
5487 features: channelmanager::provided_init_features(),
5489 unspendable_punishment_reserve: 0,
5490 forwarding_info: None,
5491 outbound_htlc_minimum_msat: None,
5492 outbound_htlc_maximum_msat: None,
5494 funding_txo: Some(OutPoint {
5495 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5498 short_channel_id: Some(1),
5499 inbound_scid_alias: None,
5500 outbound_scid_alias: None,
5501 channel_value_satoshis: 10_000_000,
5503 balance_msat: 10_000_000,
5504 outbound_capacity_msat: 10_000_000,
5505 next_outbound_htlc_limit_msat: 10_000_000,
5506 inbound_capacity_msat: 0,
5507 unspendable_punishment_reserve: None,
5508 confirmations_required: None,
5509 force_close_spend_delay: None,
5511 is_channel_ready: true,
5514 inbound_htlc_minimum_msat: None,
5515 inbound_htlc_maximum_msat: None,
5521 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5522 let logger = DummyLogger {};
5523 let network_graph = read_network_graph(&logger);
5524 let scorer = FixedPenaltyScorer::with_penalty(0);
5525 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5529 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5530 let logger = DummyLogger {};
5531 let network_graph = read_network_graph(&logger);
5532 let scorer = FixedPenaltyScorer::with_penalty(0);
5533 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
5537 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5538 let logger = DummyLogger {};
5539 let network_graph = read_network_graph(&logger);
5540 let params = ProbabilisticScoringParameters::default();
5541 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5542 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5546 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5547 let logger = DummyLogger {};
5548 let network_graph = read_network_graph(&logger);
5549 let params = ProbabilisticScoringParameters::default();
5550 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5551 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
5554 fn generate_routes<S: Score>(
5555 bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
5556 features: InvoiceFeatures
5558 let nodes = graph.read_only().nodes().clone();
5559 let payer = payer_pubkey();
5560 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5561 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5563 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5564 let mut routes = Vec::new();
5565 let mut route_endpoints = Vec::new();
5566 let mut seed: usize = 0xdeadbeef;
5567 'load_endpoints: for _ in 0..150 {
5570 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5572 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5573 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5574 let first_hop = first_hop(src);
5575 let amt = seed as u64 % 1_000_000;
5576 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5578 route_endpoints.push((first_hop, params, amt));
5579 continue 'load_endpoints;
5584 // ...and seed the scorer with success and failure data...
5585 for route in routes {
5586 let amount = route.get_total_amount();
5587 if amount < 250_000 {
5588 for path in route.paths {
5589 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5591 } else if amount > 750_000 {
5592 for path in route.paths {
5593 let short_channel_id = path[path.len() / 2].short_channel_id;
5594 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5599 // Because we've changed channel scores, its possible we'll take different routes to the
5600 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5601 // requires a too-high CLTV delta.
5602 route_endpoints.retain(|(first_hop, params, amt)| {
5603 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5605 route_endpoints.truncate(100);
5606 assert_eq!(route_endpoints.len(), 100);
5608 // ...then benchmark finding paths between the nodes we learned.
5611 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5612 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());