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 ln::channelmanager::ChannelDetails;
18 use ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
19 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
20 use routing::gossip::{DirectedChannelInfoWithUpdate, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
21 use routing::scoring::{ChannelUsage, Score};
22 use util::ser::{Writeable, Readable, Writer};
23 use util::logger::{Level, Logger};
24 use util::chacha20::ChaCha20;
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: ::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, 1)),
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: 1,
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: ::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. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
800 // 7. Of all the found paths, select only those with the lowest total fee.
801 // 8. The last path in every selected route is likely to be more than we need.
802 // Reduce its value-to-transfer and recompute fees.
803 // 9. Choose the best route by the lowest total fee.
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: 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});
1658 // Sort by total fees and take the best paths.
1659 payment_paths.sort_unstable_by_key(|path| path.get_total_fee_paid_msat());
1660 if payment_paths.len() > 50 {
1661 payment_paths.truncate(50);
1664 // Draw multiple sufficient routes by randomly combining the selected paths.
1665 let mut drawn_routes = Vec::new();
1666 let mut prng = ChaCha20::new(random_seed_bytes, &[0u8; 12]);
1667 let mut random_index_bytes = [0u8; ::core::mem::size_of::<usize>()];
1669 let num_permutations = payment_paths.len();
1670 for _ in 0..num_permutations {
1671 let mut cur_route = Vec::<PaymentPath>::new();
1672 let mut aggregate_route_value_msat = 0;
1675 // Do a Fisher-Yates shuffle to create a random permutation of the payment paths
1676 for cur_index in (1..payment_paths.len()).rev() {
1677 prng.process_in_place(&mut random_index_bytes);
1678 let random_index = usize::from_be_bytes(random_index_bytes).wrapping_rem(cur_index+1);
1679 payment_paths.swap(cur_index, random_index);
1683 for payment_path in &payment_paths {
1684 cur_route.push(payment_path.clone());
1685 aggregate_route_value_msat += payment_path.get_value_msat();
1686 if aggregate_route_value_msat > final_value_msat {
1687 // Last path likely overpaid. Substract it from the most expensive
1688 // (in terms of proportional fee) path in this route and recompute fees.
1689 // This might be not the most economically efficient way, but fewer paths
1690 // also makes routing more reliable.
1691 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1693 // First, we drop some expensive low-value paths entirely if possible, since fewer
1694 // paths is better: the payment is less likely to fail. In order to do so, we sort
1695 // by value and fall back to total fees paid, i.e., in case of equal values we
1696 // prefer lower cost paths.
1697 cur_route.sort_unstable_by(|a, b| {
1698 a.get_value_msat().cmp(&b.get_value_msat())
1699 // Reverse ordering for cost, so we drop higher-cost paths first
1700 .then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1703 // We should make sure that at least 1 path left.
1704 let mut paths_left = cur_route.len();
1705 cur_route.retain(|path| {
1706 if paths_left == 1 {
1709 let mut keep = true;
1710 let path_value_msat = path.get_value_msat();
1711 if path_value_msat <= overpaid_value_msat {
1713 overpaid_value_msat -= path_value_msat;
1719 if overpaid_value_msat == 0 {
1723 assert!(cur_route.len() > 0);
1726 // Now, subtract the overpaid value from the most-expensive path.
1727 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1728 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1729 cur_route.sort_unstable_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1730 let expensive_payment_path = cur_route.first_mut().unwrap();
1732 // We already dropped all the small value paths above, meaning all the
1733 // remaining paths are larger than remaining overpaid_value_msat.
1734 // Thus, this can't be negative.
1735 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1736 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1740 drawn_routes.push(cur_route);
1744 // Select the best route by lowest total cost.
1745 drawn_routes.sort_unstable_by_key(|paths| paths.iter().map(|path| path.get_cost_msat()).sum::<u64>());
1746 let selected_route = drawn_routes.first_mut().unwrap();
1748 // Sort by the path itself and combine redundant paths.
1749 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
1750 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
1752 selected_route.sort_unstable_by_key(|path| {
1753 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
1754 debug_assert!(path.hops.len() <= key.len());
1755 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
1760 for idx in 0..(selected_route.len() - 1) {
1761 if idx + 1 >= selected_route.len() { break; }
1762 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
1763 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
1764 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
1765 selected_route[idx].update_value_and_recompute_fees(new_value);
1766 selected_route.remove(idx + 1);
1770 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1771 for payment_path in selected_route {
1772 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1774 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)})?,
1775 node_features: node_features.clone(),
1776 short_channel_id: payment_hop.candidate.short_channel_id(),
1777 channel_features: payment_hop.candidate.features(),
1778 fee_msat: payment_hop.fee_msat,
1779 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1781 }).collect::<Vec<_>>();
1782 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1783 // applicable for the previous hop.
1784 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1785 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1787 selected_paths.push(path);
1789 // Make sure we would never create a route with more paths than we allow.
1790 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
1792 if let Some(features) = &payment_params.features {
1793 for path in selected_paths.iter_mut() {
1794 if let Ok(route_hop) = path.last_mut().unwrap() {
1795 route_hop.node_features = features.to_context();
1801 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1802 payment_params: Some(payment_params.clone()),
1804 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1808 // When an adversarial intermediary node observes a payment, it may be able to infer its
1809 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1810 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1811 // payment path by adding a randomized 'shadow route' offset to the final hop.
1812 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
1813 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
1815 let network_channels = network_graph.channels();
1816 let network_nodes = network_graph.nodes();
1818 for path in route.paths.iter_mut() {
1819 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1821 // Remember the last three nodes of the random walk and avoid looping back on them.
1822 // Init with the last three nodes from the actual path, if possible.
1823 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1824 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1825 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1827 // Choose the last publicly known node as the starting point for the random walk.
1828 let mut cur_hop: Option<NodeId> = None;
1829 let mut path_nonce = [0u8; 12];
1830 if let Some(starting_hop) = path.iter().rev()
1831 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1832 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1833 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1836 // Init PRNG with the path-dependant nonce, which is static for private paths.
1837 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1838 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1840 // Pick a random path length in [1 .. 3]
1841 prng.process_in_place(&mut random_path_bytes);
1842 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1844 for random_hop in 0..random_walk_length {
1845 // If we don't find a suitable offset in the public network graph, we default to
1846 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1847 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1849 if let Some(cur_node_id) = cur_hop {
1850 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1851 // Randomly choose the next unvisited hop.
1852 prng.process_in_place(&mut random_path_bytes);
1853 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1854 .checked_rem(cur_node.channels.len())
1855 .and_then(|index| cur_node.channels.get(index))
1856 .and_then(|id| network_channels.get(id)) {
1857 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1858 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1859 nodes_to_avoid[random_hop] = *next_id;
1860 dir_info.direction().map(|channel_update_info| {
1861 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1862 cur_hop = Some(*next_id);
1870 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1871 .checked_add(random_hop_offset)
1872 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1875 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1876 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1877 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1879 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1880 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1881 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1882 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1883 max_path_offset = cmp::max(
1884 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1885 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1886 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1888 // Add 'shadow' CLTV offset to the final hop
1889 if let Some(last_hop) = path.last_mut() {
1890 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1891 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1896 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
1897 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
1899 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
1900 pub fn build_route_from_hops<L: Deref, GL: Deref>(
1901 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
1902 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
1903 ) -> Result<Route, LightningError>
1904 where L::Target: Logger, GL::Target: Logger {
1905 let graph_lock = network_graph.read_only();
1906 let mut route = build_route_from_hops_internal(
1907 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
1908 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
1909 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1913 fn build_route_from_hops_internal<L: Deref>(
1914 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
1915 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
1916 logger: L, random_seed_bytes: &[u8; 32]
1917 ) -> Result<Route, LightningError> where L::Target: Logger {
1920 our_node_id: NodeId,
1921 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
1924 impl Score for HopScorer {
1925 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
1926 _usage: ChannelUsage) -> u64
1928 let mut cur_id = self.our_node_id;
1929 for i in 0..self.hop_ids.len() {
1930 if let Some(next_id) = self.hop_ids[i] {
1931 if cur_id == *source && next_id == *target {
1942 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1944 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
1946 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1948 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
1951 impl<'a> Writeable for HopScorer {
1953 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
1958 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
1959 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
1962 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
1963 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
1964 for i in 0..hops.len() {
1965 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
1968 let scorer = HopScorer { our_node_id, hop_ids };
1970 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
1971 final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)
1976 use routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
1977 use routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
1978 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
1979 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
1980 use routing::scoring::{ChannelUsage, Score, ProbabilisticScorer, ProbabilisticScoringParameters};
1981 use chain::transaction::OutPoint;
1982 use chain::keysinterface::KeysInterface;
1983 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1984 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1985 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1986 use ln::channelmanager;
1987 use util::test_utils;
1988 use util::chacha20::ChaCha20;
1989 use util::ser::Writeable;
1991 use util::ser::Writer;
1993 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1994 use bitcoin::hashes::Hash;
1995 use bitcoin::network::constants::Network;
1996 use bitcoin::blockdata::constants::genesis_block;
1997 use bitcoin::blockdata::script::Builder;
1998 use bitcoin::blockdata::opcodes;
1999 use bitcoin::blockdata::transaction::TxOut;
2003 use bitcoin::secp256k1::{PublicKey,SecretKey};
2004 use bitcoin::secp256k1::{Secp256k1, All};
2007 use sync::{self, Arc};
2009 use core::convert::TryInto;
2011 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2012 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2013 channelmanager::ChannelDetails {
2014 channel_id: [0; 32],
2015 counterparty: channelmanager::ChannelCounterparty {
2018 unspendable_punishment_reserve: 0,
2019 forwarding_info: None,
2020 outbound_htlc_minimum_msat: None,
2021 outbound_htlc_maximum_msat: None,
2023 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2026 outbound_scid_alias: None,
2027 inbound_scid_alias: None,
2028 channel_value_satoshis: 0,
2031 outbound_capacity_msat,
2032 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2033 inbound_capacity_msat: 42,
2034 unspendable_punishment_reserve: None,
2035 confirmations_required: None,
2036 force_close_spend_delay: None,
2037 is_outbound: true, is_channel_ready: true,
2038 is_usable: true, is_public: true,
2039 inbound_htlc_minimum_msat: None,
2040 inbound_htlc_maximum_msat: None,
2045 // Using the same keys for LN and BTC ids
2047 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2048 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
2050 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
2051 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
2053 let unsigned_announcement = UnsignedChannelAnnouncement {
2055 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2059 bitcoin_key_1: node_id_1,
2060 bitcoin_key_2: node_id_2,
2061 excess_data: Vec::new(),
2064 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
2065 let valid_announcement = ChannelAnnouncement {
2066 node_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
2067 node_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
2068 bitcoin_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
2069 bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
2070 contents: unsigned_announcement.clone(),
2072 match gossip_sync.handle_channel_announcement(&valid_announcement) {
2073 Ok(res) => assert!(res),
2079 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2080 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
2082 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
2083 let valid_channel_update = ChannelUpdate {
2084 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
2085 contents: update.clone()
2088 match gossip_sync.handle_channel_update(&valid_channel_update) {
2089 Ok(res) => assert!(res),
2094 fn add_or_update_node(
2095 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2096 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
2098 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
2099 let unsigned_announcement = UnsignedNodeAnnouncement {
2105 addresses: Vec::new(),
2106 excess_address_data: Vec::new(),
2107 excess_data: Vec::new(),
2109 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
2110 let valid_announcement = NodeAnnouncement {
2111 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
2112 contents: unsigned_announcement.clone()
2115 match gossip_sync.handle_node_announcement(&valid_announcement) {
2121 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
2122 let privkeys: Vec<SecretKey> = (2..22).map(|i| {
2123 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
2126 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
2128 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
2129 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
2131 (our_privkey, our_id, privkeys, pubkeys)
2134 fn id_to_feature_flags(id: u8) -> Vec<u8> {
2135 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
2136 // test for it later.
2137 let idx = (id - 1) * 2 + 1;
2139 vec![1 << (idx - 8*3), 0, 0, 0]
2140 } else if idx > 8*2 {
2141 vec![1 << (idx - 8*2), 0, 0]
2142 } else if idx > 8*1 {
2143 vec![1 << (idx - 8*1), 0]
2149 fn build_line_graph() -> (
2150 Secp256k1<All>, sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
2151 P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
2152 sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>,
2154 let secp_ctx = Secp256k1::new();
2155 let logger = Arc::new(test_utils::TestLogger::new());
2156 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
2157 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
2158 let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
2159 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
2161 // Build network from our_id to node 19:
2162 // our_id -1(1)2- node0 -1(2)2- node1 - ... - node19
2163 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
2165 for (idx, (cur_privkey, next_privkey)) in core::iter::once(&our_privkey)
2166 .chain(privkeys.iter()).zip(privkeys.iter()).enumerate() {
2167 let cur_short_channel_id = (idx as u64) + 1;
2168 add_channel(&gossip_sync, &secp_ctx, &cur_privkey, &next_privkey,
2169 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), cur_short_channel_id);
2170 update_channel(&gossip_sync, &secp_ctx, &cur_privkey, UnsignedChannelUpdate {
2171 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2172 short_channel_id: cur_short_channel_id,
2173 timestamp: idx as u32,
2175 cltv_expiry_delta: 0,
2176 htlc_minimum_msat: 0,
2177 htlc_maximum_msat: OptionalField::Absent,
2179 fee_proportional_millionths: 0,
2180 excess_data: Vec::new()
2182 update_channel(&gossip_sync, &secp_ctx, &next_privkey, UnsignedChannelUpdate {
2183 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2184 short_channel_id: cur_short_channel_id,
2185 timestamp: (idx as u32)+1,
2187 cltv_expiry_delta: 0,
2188 htlc_minimum_msat: 0,
2189 htlc_maximum_msat: OptionalField::Absent,
2191 fee_proportional_millionths: 0,
2192 excess_data: Vec::new()
2194 add_or_update_node(&gossip_sync, &secp_ctx, next_privkey,
2195 NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
2198 (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
2201 fn build_graph() -> (
2203 sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
2204 P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
2205 sync::Arc<test_utils::TestChainSource>,
2206 sync::Arc<test_utils::TestLogger>,
2208 let secp_ctx = Secp256k1::new();
2209 let logger = Arc::new(test_utils::TestLogger::new());
2210 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
2211 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
2212 let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
2213 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
2214 // Build network from our_id to node6:
2216 // -1(1)2- node0 -1(3)2-
2218 // our_id -1(12)2- node7 -1(13)2--- node2
2220 // -1(2)2- node1 -1(4)2-
2223 // chan1 1-to-2: disabled
2224 // chan1 2-to-1: enabled, 0 fee
2226 // chan2 1-to-2: enabled, ignored fee
2227 // chan2 2-to-1: enabled, 0 fee
2229 // chan3 1-to-2: enabled, 0 fee
2230 // chan3 2-to-1: enabled, 100 msat fee
2232 // chan4 1-to-2: enabled, 100% fee
2233 // chan4 2-to-1: enabled, 0 fee
2235 // chan12 1-to-2: enabled, ignored fee
2236 // chan12 2-to-1: enabled, 0 fee
2238 // chan13 1-to-2: enabled, 200% fee
2239 // chan13 2-to-1: enabled, 0 fee
2242 // -1(5)2- node3 -1(8)2--
2246 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
2248 // -1(7)2- node5 -1(10)2-
2250 // Channels 5, 8, 9 and 10 are private channels.
2252 // chan5 1-to-2: enabled, 100 msat fee
2253 // chan5 2-to-1: enabled, 0 fee
2255 // chan6 1-to-2: enabled, 0 fee
2256 // chan6 2-to-1: enabled, 0 fee
2258 // chan7 1-to-2: enabled, 100% fee
2259 // chan7 2-to-1: enabled, 0 fee
2261 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
2262 // chan8 2-to-1: enabled, 0 fee
2264 // chan9 1-to-2: enabled, 1001 msat fee
2265 // chan9 2-to-1: enabled, 0 fee
2267 // chan10 1-to-2: enabled, 0 fee
2268 // chan10 2-to-1: enabled, 0 fee
2270 // chan11 1-to-2: enabled, 0 fee
2271 // chan11 2-to-1: enabled, 0 fee
2273 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
2275 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
2276 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2277 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2278 short_channel_id: 1,
2281 cltv_expiry_delta: 0,
2282 htlc_minimum_msat: 0,
2283 htlc_maximum_msat: OptionalField::Absent,
2285 fee_proportional_millionths: 0,
2286 excess_data: Vec::new()
2289 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
2291 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
2292 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2293 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2294 short_channel_id: 2,
2297 cltv_expiry_delta: (5 << 4) | 3,
2298 htlc_minimum_msat: 0,
2299 htlc_maximum_msat: OptionalField::Absent,
2300 fee_base_msat: u32::max_value(),
2301 fee_proportional_millionths: u32::max_value(),
2302 excess_data: Vec::new()
2304 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2306 short_channel_id: 2,
2309 cltv_expiry_delta: 0,
2310 htlc_minimum_msat: 0,
2311 htlc_maximum_msat: OptionalField::Absent,
2313 fee_proportional_millionths: 0,
2314 excess_data: Vec::new()
2317 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
2319 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
2320 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2321 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2322 short_channel_id: 12,
2325 cltv_expiry_delta: (5 << 4) | 3,
2326 htlc_minimum_msat: 0,
2327 htlc_maximum_msat: OptionalField::Absent,
2328 fee_base_msat: u32::max_value(),
2329 fee_proportional_millionths: u32::max_value(),
2330 excess_data: Vec::new()
2332 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2333 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2334 short_channel_id: 12,
2337 cltv_expiry_delta: 0,
2338 htlc_minimum_msat: 0,
2339 htlc_maximum_msat: OptionalField::Absent,
2341 fee_proportional_millionths: 0,
2342 excess_data: Vec::new()
2345 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
2347 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
2348 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2349 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2350 short_channel_id: 3,
2353 cltv_expiry_delta: (3 << 4) | 1,
2354 htlc_minimum_msat: 0,
2355 htlc_maximum_msat: OptionalField::Absent,
2357 fee_proportional_millionths: 0,
2358 excess_data: Vec::new()
2360 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2361 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2362 short_channel_id: 3,
2365 cltv_expiry_delta: (3 << 4) | 2,
2366 htlc_minimum_msat: 0,
2367 htlc_maximum_msat: OptionalField::Absent,
2369 fee_proportional_millionths: 0,
2370 excess_data: Vec::new()
2373 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2374 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2375 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2376 short_channel_id: 4,
2379 cltv_expiry_delta: (4 << 4) | 1,
2380 htlc_minimum_msat: 0,
2381 htlc_maximum_msat: OptionalField::Absent,
2383 fee_proportional_millionths: 1000000,
2384 excess_data: Vec::new()
2386 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2387 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2388 short_channel_id: 4,
2391 cltv_expiry_delta: (4 << 4) | 2,
2392 htlc_minimum_msat: 0,
2393 htlc_maximum_msat: OptionalField::Absent,
2395 fee_proportional_millionths: 0,
2396 excess_data: Vec::new()
2399 add_channel(&gossip_sync, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2400 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2401 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2402 short_channel_id: 13,
2405 cltv_expiry_delta: (13 << 4) | 1,
2406 htlc_minimum_msat: 0,
2407 htlc_maximum_msat: OptionalField::Absent,
2409 fee_proportional_millionths: 2000000,
2410 excess_data: Vec::new()
2412 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2413 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2414 short_channel_id: 13,
2417 cltv_expiry_delta: (13 << 4) | 2,
2418 htlc_minimum_msat: 0,
2419 htlc_maximum_msat: OptionalField::Absent,
2421 fee_proportional_millionths: 0,
2422 excess_data: Vec::new()
2425 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2427 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2428 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2429 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2430 short_channel_id: 6,
2433 cltv_expiry_delta: (6 << 4) | 1,
2434 htlc_minimum_msat: 0,
2435 htlc_maximum_msat: OptionalField::Absent,
2437 fee_proportional_millionths: 0,
2438 excess_data: Vec::new()
2440 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2441 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2442 short_channel_id: 6,
2445 cltv_expiry_delta: (6 << 4) | 2,
2446 htlc_minimum_msat: 0,
2447 htlc_maximum_msat: OptionalField::Absent,
2449 fee_proportional_millionths: 0,
2450 excess_data: Vec::new(),
2453 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2454 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2455 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2456 short_channel_id: 11,
2459 cltv_expiry_delta: (11 << 4) | 1,
2460 htlc_minimum_msat: 0,
2461 htlc_maximum_msat: OptionalField::Absent,
2463 fee_proportional_millionths: 0,
2464 excess_data: Vec::new()
2466 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2467 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2468 short_channel_id: 11,
2471 cltv_expiry_delta: (11 << 4) | 2,
2472 htlc_minimum_msat: 0,
2473 htlc_maximum_msat: OptionalField::Absent,
2475 fee_proportional_millionths: 0,
2476 excess_data: Vec::new()
2479 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2481 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2483 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2484 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2485 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2486 short_channel_id: 7,
2489 cltv_expiry_delta: (7 << 4) | 1,
2490 htlc_minimum_msat: 0,
2491 htlc_maximum_msat: OptionalField::Absent,
2493 fee_proportional_millionths: 1000000,
2494 excess_data: Vec::new()
2496 update_channel(&gossip_sync, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2497 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2498 short_channel_id: 7,
2501 cltv_expiry_delta: (7 << 4) | 2,
2502 htlc_minimum_msat: 0,
2503 htlc_maximum_msat: OptionalField::Absent,
2505 fee_proportional_millionths: 0,
2506 excess_data: Vec::new()
2509 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2511 (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
2515 fn simple_route_test() {
2516 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2517 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2518 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2519 let scorer = test_utils::TestScorer::with_penalty(0);
2520 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2521 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2523 // Simple route to 2 via 1
2525 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) {
2526 assert_eq!(err, "Cannot send a payment of 0 msat");
2527 } else { panic!(); }
2529 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2530 assert_eq!(route.paths[0].len(), 2);
2532 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2533 assert_eq!(route.paths[0][0].short_channel_id, 2);
2534 assert_eq!(route.paths[0][0].fee_msat, 100);
2535 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2536 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2537 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2539 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2540 assert_eq!(route.paths[0][1].short_channel_id, 4);
2541 assert_eq!(route.paths[0][1].fee_msat, 100);
2542 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2543 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2544 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2548 fn invalid_first_hop_test() {
2549 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2550 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2551 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2552 let scorer = test_utils::TestScorer::with_penalty(0);
2553 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2554 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2556 // Simple route to 2 via 1
2558 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2560 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2561 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) {
2562 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2563 } else { panic!(); }
2565 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2566 assert_eq!(route.paths[0].len(), 2);
2570 fn htlc_minimum_test() {
2571 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2572 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2573 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2574 let scorer = test_utils::TestScorer::with_penalty(0);
2575 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2576 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2578 // Simple route to 2 via 1
2580 // Disable other paths
2581 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2582 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2583 short_channel_id: 12,
2585 flags: 2, // to disable
2586 cltv_expiry_delta: 0,
2587 htlc_minimum_msat: 0,
2588 htlc_maximum_msat: OptionalField::Absent,
2590 fee_proportional_millionths: 0,
2591 excess_data: Vec::new()
2593 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2594 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2595 short_channel_id: 3,
2597 flags: 2, // to disable
2598 cltv_expiry_delta: 0,
2599 htlc_minimum_msat: 0,
2600 htlc_maximum_msat: OptionalField::Absent,
2602 fee_proportional_millionths: 0,
2603 excess_data: Vec::new()
2605 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2606 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2607 short_channel_id: 13,
2609 flags: 2, // to disable
2610 cltv_expiry_delta: 0,
2611 htlc_minimum_msat: 0,
2612 htlc_maximum_msat: OptionalField::Absent,
2614 fee_proportional_millionths: 0,
2615 excess_data: Vec::new()
2617 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2618 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2619 short_channel_id: 6,
2621 flags: 2, // to disable
2622 cltv_expiry_delta: 0,
2623 htlc_minimum_msat: 0,
2624 htlc_maximum_msat: OptionalField::Absent,
2626 fee_proportional_millionths: 0,
2627 excess_data: Vec::new()
2629 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2630 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2631 short_channel_id: 7,
2633 flags: 2, // to disable
2634 cltv_expiry_delta: 0,
2635 htlc_minimum_msat: 0,
2636 htlc_maximum_msat: OptionalField::Absent,
2638 fee_proportional_millionths: 0,
2639 excess_data: Vec::new()
2642 // Check against amount_to_transfer_over_msat.
2643 // Set minimal HTLC of 200_000_000 msat.
2644 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2645 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2646 short_channel_id: 2,
2649 cltv_expiry_delta: 0,
2650 htlc_minimum_msat: 200_000_000,
2651 htlc_maximum_msat: OptionalField::Absent,
2653 fee_proportional_millionths: 0,
2654 excess_data: Vec::new()
2657 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2659 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2660 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2661 short_channel_id: 4,
2664 cltv_expiry_delta: 0,
2665 htlc_minimum_msat: 0,
2666 htlc_maximum_msat: OptionalField::Present(199_999_999),
2668 fee_proportional_millionths: 0,
2669 excess_data: Vec::new()
2672 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2673 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) {
2674 assert_eq!(err, "Failed to find a path to the given destination");
2675 } else { panic!(); }
2677 // Lift the restriction on the first hop.
2678 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2679 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2680 short_channel_id: 2,
2683 cltv_expiry_delta: 0,
2684 htlc_minimum_msat: 0,
2685 htlc_maximum_msat: OptionalField::Absent,
2687 fee_proportional_millionths: 0,
2688 excess_data: Vec::new()
2691 // A payment above the minimum should pass
2692 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();
2693 assert_eq!(route.paths[0].len(), 2);
2697 fn htlc_minimum_overpay_test() {
2698 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2699 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2700 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2701 let scorer = test_utils::TestScorer::with_penalty(0);
2702 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2703 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2705 // A route to node#2 via two paths.
2706 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2707 // Thus, they can't send 60 without overpaying.
2708 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2709 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2710 short_channel_id: 2,
2713 cltv_expiry_delta: 0,
2714 htlc_minimum_msat: 35_000,
2715 htlc_maximum_msat: OptionalField::Present(40_000),
2717 fee_proportional_millionths: 0,
2718 excess_data: Vec::new()
2720 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2721 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2722 short_channel_id: 12,
2725 cltv_expiry_delta: 0,
2726 htlc_minimum_msat: 35_000,
2727 htlc_maximum_msat: OptionalField::Present(40_000),
2729 fee_proportional_millionths: 0,
2730 excess_data: Vec::new()
2734 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2735 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2736 short_channel_id: 13,
2739 cltv_expiry_delta: 0,
2740 htlc_minimum_msat: 0,
2741 htlc_maximum_msat: OptionalField::Absent,
2743 fee_proportional_millionths: 0,
2744 excess_data: Vec::new()
2746 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2747 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2748 short_channel_id: 4,
2751 cltv_expiry_delta: 0,
2752 htlc_minimum_msat: 0,
2753 htlc_maximum_msat: OptionalField::Absent,
2755 fee_proportional_millionths: 0,
2756 excess_data: Vec::new()
2759 // Disable other paths
2760 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2761 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2762 short_channel_id: 1,
2764 flags: 2, // to disable
2765 cltv_expiry_delta: 0,
2766 htlc_minimum_msat: 0,
2767 htlc_maximum_msat: OptionalField::Absent,
2769 fee_proportional_millionths: 0,
2770 excess_data: Vec::new()
2773 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2774 // Overpay fees to hit htlc_minimum_msat.
2775 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2776 // TODO: this could be better balanced to overpay 10k and not 15k.
2777 assert_eq!(overpaid_fees, 15_000);
2779 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2780 // while taking even more fee to match htlc_minimum_msat.
2781 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2782 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2783 short_channel_id: 12,
2786 cltv_expiry_delta: 0,
2787 htlc_minimum_msat: 65_000,
2788 htlc_maximum_msat: OptionalField::Present(80_000),
2790 fee_proportional_millionths: 0,
2791 excess_data: Vec::new()
2793 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2794 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2795 short_channel_id: 2,
2798 cltv_expiry_delta: 0,
2799 htlc_minimum_msat: 0,
2800 htlc_maximum_msat: OptionalField::Absent,
2802 fee_proportional_millionths: 0,
2803 excess_data: Vec::new()
2805 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2806 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2807 short_channel_id: 4,
2810 cltv_expiry_delta: 0,
2811 htlc_minimum_msat: 0,
2812 htlc_maximum_msat: OptionalField::Absent,
2814 fee_proportional_millionths: 100_000,
2815 excess_data: Vec::new()
2818 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2819 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2820 assert_eq!(route.paths.len(), 1);
2821 assert_eq!(route.paths[0][0].short_channel_id, 12);
2822 let fees = route.paths[0][0].fee_msat;
2823 assert_eq!(fees, 5_000);
2825 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2826 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2827 // the other channel.
2828 assert_eq!(route.paths.len(), 1);
2829 assert_eq!(route.paths[0][0].short_channel_id, 2);
2830 let fees = route.paths[0][0].fee_msat;
2831 assert_eq!(fees, 5_000);
2835 fn disable_channels_test() {
2836 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2837 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2838 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2839 let scorer = test_utils::TestScorer::with_penalty(0);
2840 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2841 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2843 // // Disable channels 4 and 12 by flags=2
2844 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2845 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2846 short_channel_id: 4,
2848 flags: 2, // to disable
2849 cltv_expiry_delta: 0,
2850 htlc_minimum_msat: 0,
2851 htlc_maximum_msat: OptionalField::Absent,
2853 fee_proportional_millionths: 0,
2854 excess_data: Vec::new()
2856 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2857 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2858 short_channel_id: 12,
2860 flags: 2, // to disable
2861 cltv_expiry_delta: 0,
2862 htlc_minimum_msat: 0,
2863 htlc_maximum_msat: OptionalField::Absent,
2865 fee_proportional_millionths: 0,
2866 excess_data: Vec::new()
2869 // If all the channels require some features we don't understand, route should fail
2870 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) {
2871 assert_eq!(err, "Failed to find a path to the given destination");
2872 } else { panic!(); }
2874 // If we specify a channel to node7, that overrides our local channel view and that gets used
2875 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2876 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();
2877 assert_eq!(route.paths[0].len(), 2);
2879 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2880 assert_eq!(route.paths[0][0].short_channel_id, 42);
2881 assert_eq!(route.paths[0][0].fee_msat, 200);
2882 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2883 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2884 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2886 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2887 assert_eq!(route.paths[0][1].short_channel_id, 13);
2888 assert_eq!(route.paths[0][1].fee_msat, 100);
2889 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2890 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2891 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2895 fn disable_node_test() {
2896 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2897 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2898 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2899 let scorer = test_utils::TestScorer::with_penalty(0);
2900 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2901 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2903 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2904 let mut unknown_features = NodeFeatures::known();
2905 unknown_features.set_unknown_feature_required();
2906 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2907 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2908 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2910 // If all nodes require some features we don't understand, route should fail
2911 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) {
2912 assert_eq!(err, "Failed to find a path to the given destination");
2913 } else { panic!(); }
2915 // If we specify a channel to node7, that overrides our local channel view and that gets used
2916 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2917 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();
2918 assert_eq!(route.paths[0].len(), 2);
2920 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2921 assert_eq!(route.paths[0][0].short_channel_id, 42);
2922 assert_eq!(route.paths[0][0].fee_msat, 200);
2923 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2924 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2925 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2927 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2928 assert_eq!(route.paths[0][1].short_channel_id, 13);
2929 assert_eq!(route.paths[0][1].fee_msat, 100);
2930 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2931 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2932 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2934 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2935 // naively) assume that the user checked the feature bits on the invoice, which override
2936 // the node_announcement.
2940 fn our_chans_test() {
2941 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2942 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2943 let scorer = test_utils::TestScorer::with_penalty(0);
2944 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2945 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2947 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2948 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2949 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2950 assert_eq!(route.paths[0].len(), 3);
2952 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2953 assert_eq!(route.paths[0][0].short_channel_id, 2);
2954 assert_eq!(route.paths[0][0].fee_msat, 200);
2955 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2956 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2957 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2959 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2960 assert_eq!(route.paths[0][1].short_channel_id, 4);
2961 assert_eq!(route.paths[0][1].fee_msat, 100);
2962 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2963 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2964 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2966 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2967 assert_eq!(route.paths[0][2].short_channel_id, 3);
2968 assert_eq!(route.paths[0][2].fee_msat, 100);
2969 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2970 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2971 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2973 // If we specify a channel to node7, that overrides our local channel view and that gets used
2974 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2975 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2976 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();
2977 assert_eq!(route.paths[0].len(), 2);
2979 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2980 assert_eq!(route.paths[0][0].short_channel_id, 42);
2981 assert_eq!(route.paths[0][0].fee_msat, 200);
2982 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2983 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2984 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2986 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2987 assert_eq!(route.paths[0][1].short_channel_id, 13);
2988 assert_eq!(route.paths[0][1].fee_msat, 100);
2989 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2990 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2991 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2994 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2995 let zero_fees = RoutingFees {
2997 proportional_millionths: 0,
2999 vec![RouteHint(vec![RouteHintHop {
3000 src_node_id: nodes[3],
3001 short_channel_id: 8,
3003 cltv_expiry_delta: (8 << 4) | 1,
3004 htlc_minimum_msat: None,
3005 htlc_maximum_msat: None,
3007 ]), RouteHint(vec![RouteHintHop {
3008 src_node_id: nodes[4],
3009 short_channel_id: 9,
3012 proportional_millionths: 0,
3014 cltv_expiry_delta: (9 << 4) | 1,
3015 htlc_minimum_msat: None,
3016 htlc_maximum_msat: None,
3017 }]), RouteHint(vec![RouteHintHop {
3018 src_node_id: nodes[5],
3019 short_channel_id: 10,
3021 cltv_expiry_delta: (10 << 4) | 1,
3022 htlc_minimum_msat: None,
3023 htlc_maximum_msat: None,
3027 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3028 let zero_fees = RoutingFees {
3030 proportional_millionths: 0,
3032 vec![RouteHint(vec![RouteHintHop {
3033 src_node_id: nodes[2],
3034 short_channel_id: 5,
3037 proportional_millionths: 0,
3039 cltv_expiry_delta: (5 << 4) | 1,
3040 htlc_minimum_msat: None,
3041 htlc_maximum_msat: None,
3043 src_node_id: nodes[3],
3044 short_channel_id: 8,
3046 cltv_expiry_delta: (8 << 4) | 1,
3047 htlc_minimum_msat: None,
3048 htlc_maximum_msat: None,
3050 ]), RouteHint(vec![RouteHintHop {
3051 src_node_id: nodes[4],
3052 short_channel_id: 9,
3055 proportional_millionths: 0,
3057 cltv_expiry_delta: (9 << 4) | 1,
3058 htlc_minimum_msat: None,
3059 htlc_maximum_msat: None,
3060 }]), RouteHint(vec![RouteHintHop {
3061 src_node_id: nodes[5],
3062 short_channel_id: 10,
3064 cltv_expiry_delta: (10 << 4) | 1,
3065 htlc_minimum_msat: None,
3066 htlc_maximum_msat: None,
3071 fn partial_route_hint_test() {
3072 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3073 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3074 let scorer = test_utils::TestScorer::with_penalty(0);
3075 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3076 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3078 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3079 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3080 // RouteHint may be partially used by the algo to build the best path.
3082 // First check that last hop can't have its source as the payee.
3083 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3084 src_node_id: nodes[6],
3085 short_channel_id: 8,
3088 proportional_millionths: 0,
3090 cltv_expiry_delta: (8 << 4) | 1,
3091 htlc_minimum_msat: None,
3092 htlc_maximum_msat: None,
3095 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3096 invalid_last_hops.push(invalid_last_hop);
3098 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
3099 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) {
3100 assert_eq!(err, "Route hint cannot have the payee as the source.");
3101 } else { panic!(); }
3104 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
3105 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3106 assert_eq!(route.paths[0].len(), 5);
3108 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3109 assert_eq!(route.paths[0][0].short_channel_id, 2);
3110 assert_eq!(route.paths[0][0].fee_msat, 100);
3111 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3112 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3113 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3115 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3116 assert_eq!(route.paths[0][1].short_channel_id, 4);
3117 assert_eq!(route.paths[0][1].fee_msat, 0);
3118 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3119 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3120 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3122 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3123 assert_eq!(route.paths[0][2].short_channel_id, 6);
3124 assert_eq!(route.paths[0][2].fee_msat, 0);
3125 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3126 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3127 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3129 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3130 assert_eq!(route.paths[0][3].short_channel_id, 11);
3131 assert_eq!(route.paths[0][3].fee_msat, 0);
3132 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3133 // If we have a peer in the node map, we'll use their features here since we don't have
3134 // a way of figuring out their features from the invoice:
3135 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3136 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3138 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3139 assert_eq!(route.paths[0][4].short_channel_id, 8);
3140 assert_eq!(route.paths[0][4].fee_msat, 100);
3141 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3142 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3143 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3146 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3147 let zero_fees = RoutingFees {
3149 proportional_millionths: 0,
3151 vec![RouteHint(vec![RouteHintHop {
3152 src_node_id: nodes[3],
3153 short_channel_id: 8,
3155 cltv_expiry_delta: (8 << 4) | 1,
3156 htlc_minimum_msat: None,
3157 htlc_maximum_msat: None,
3158 }]), RouteHint(vec![
3160 ]), RouteHint(vec![RouteHintHop {
3161 src_node_id: nodes[5],
3162 short_channel_id: 10,
3164 cltv_expiry_delta: (10 << 4) | 1,
3165 htlc_minimum_msat: None,
3166 htlc_maximum_msat: None,
3171 fn ignores_empty_last_hops_test() {
3172 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3173 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3174 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
3175 let scorer = test_utils::TestScorer::with_penalty(0);
3176 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3177 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3179 // Test handling of an empty RouteHint passed in Invoice.
3181 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3182 assert_eq!(route.paths[0].len(), 5);
3184 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3185 assert_eq!(route.paths[0][0].short_channel_id, 2);
3186 assert_eq!(route.paths[0][0].fee_msat, 100);
3187 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3188 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3189 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3191 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3192 assert_eq!(route.paths[0][1].short_channel_id, 4);
3193 assert_eq!(route.paths[0][1].fee_msat, 0);
3194 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3195 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3196 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3198 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3199 assert_eq!(route.paths[0][2].short_channel_id, 6);
3200 assert_eq!(route.paths[0][2].fee_msat, 0);
3201 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3202 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3203 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3205 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3206 assert_eq!(route.paths[0][3].short_channel_id, 11);
3207 assert_eq!(route.paths[0][3].fee_msat, 0);
3208 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3209 // If we have a peer in the node map, we'll use their features here since we don't have
3210 // a way of figuring out their features from the invoice:
3211 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3212 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3214 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3215 assert_eq!(route.paths[0][4].short_channel_id, 8);
3216 assert_eq!(route.paths[0][4].fee_msat, 100);
3217 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3218 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3219 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3222 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3224 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3225 let zero_fees = RoutingFees {
3227 proportional_millionths: 0,
3229 vec![RouteHint(vec![RouteHintHop {
3230 src_node_id: hint_hops[0],
3231 short_channel_id: 0xff00,
3234 proportional_millionths: 0,
3236 cltv_expiry_delta: (5 << 4) | 1,
3237 htlc_minimum_msat: None,
3238 htlc_maximum_msat: None,
3240 src_node_id: hint_hops[1],
3241 short_channel_id: 0xff01,
3243 cltv_expiry_delta: (8 << 4) | 1,
3244 htlc_minimum_msat: None,
3245 htlc_maximum_msat: None,
3250 fn multi_hint_last_hops_test() {
3251 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3252 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3253 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3254 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3255 let scorer = test_utils::TestScorer::with_penalty(0);
3256 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3257 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3258 // Test through channels 2, 3, 0xff00, 0xff01.
3259 // Test shows that multiple hop hints are considered.
3261 // Disabling channels 6 & 7 by flags=2
3262 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3263 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3264 short_channel_id: 6,
3266 flags: 2, // to disable
3267 cltv_expiry_delta: 0,
3268 htlc_minimum_msat: 0,
3269 htlc_maximum_msat: OptionalField::Absent,
3271 fee_proportional_millionths: 0,
3272 excess_data: Vec::new()
3274 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3275 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3276 short_channel_id: 7,
3278 flags: 2, // to disable
3279 cltv_expiry_delta: 0,
3280 htlc_minimum_msat: 0,
3281 htlc_maximum_msat: OptionalField::Absent,
3283 fee_proportional_millionths: 0,
3284 excess_data: Vec::new()
3287 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3288 assert_eq!(route.paths[0].len(), 4);
3290 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3291 assert_eq!(route.paths[0][0].short_channel_id, 2);
3292 assert_eq!(route.paths[0][0].fee_msat, 200);
3293 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3294 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3295 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3297 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3298 assert_eq!(route.paths[0][1].short_channel_id, 4);
3299 assert_eq!(route.paths[0][1].fee_msat, 100);
3300 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3301 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3302 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3304 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
3305 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3306 assert_eq!(route.paths[0][2].fee_msat, 0);
3307 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3308 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
3309 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3311 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3312 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3313 assert_eq!(route.paths[0][3].fee_msat, 100);
3314 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3315 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3316 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3320 fn private_multi_hint_last_hops_test() {
3321 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3322 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3324 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3325 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3327 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3328 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3329 let scorer = test_utils::TestScorer::with_penalty(0);
3330 // Test through channels 2, 3, 0xff00, 0xff01.
3331 // Test shows that multiple hop hints are considered.
3333 // Disabling channels 6 & 7 by flags=2
3334 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3335 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3336 short_channel_id: 6,
3338 flags: 2, // to disable
3339 cltv_expiry_delta: 0,
3340 htlc_minimum_msat: 0,
3341 htlc_maximum_msat: OptionalField::Absent,
3343 fee_proportional_millionths: 0,
3344 excess_data: Vec::new()
3346 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3347 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3348 short_channel_id: 7,
3350 flags: 2, // to disable
3351 cltv_expiry_delta: 0,
3352 htlc_minimum_msat: 0,
3353 htlc_maximum_msat: OptionalField::Absent,
3355 fee_proportional_millionths: 0,
3356 excess_data: Vec::new()
3359 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3360 assert_eq!(route.paths[0].len(), 4);
3362 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3363 assert_eq!(route.paths[0][0].short_channel_id, 2);
3364 assert_eq!(route.paths[0][0].fee_msat, 200);
3365 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3366 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3367 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3369 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3370 assert_eq!(route.paths[0][1].short_channel_id, 4);
3371 assert_eq!(route.paths[0][1].fee_msat, 100);
3372 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3373 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3374 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3376 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3377 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3378 assert_eq!(route.paths[0][2].fee_msat, 0);
3379 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3380 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3381 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3383 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3384 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3385 assert_eq!(route.paths[0][3].fee_msat, 100);
3386 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3387 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3388 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3391 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3392 let zero_fees = RoutingFees {
3394 proportional_millionths: 0,
3396 vec![RouteHint(vec![RouteHintHop {
3397 src_node_id: nodes[4],
3398 short_channel_id: 11,
3400 cltv_expiry_delta: (11 << 4) | 1,
3401 htlc_minimum_msat: None,
3402 htlc_maximum_msat: None,
3404 src_node_id: nodes[3],
3405 short_channel_id: 8,
3407 cltv_expiry_delta: (8 << 4) | 1,
3408 htlc_minimum_msat: None,
3409 htlc_maximum_msat: None,
3410 }]), RouteHint(vec![RouteHintHop {
3411 src_node_id: nodes[4],
3412 short_channel_id: 9,
3415 proportional_millionths: 0,
3417 cltv_expiry_delta: (9 << 4) | 1,
3418 htlc_minimum_msat: None,
3419 htlc_maximum_msat: None,
3420 }]), RouteHint(vec![RouteHintHop {
3421 src_node_id: nodes[5],
3422 short_channel_id: 10,
3424 cltv_expiry_delta: (10 << 4) | 1,
3425 htlc_minimum_msat: None,
3426 htlc_maximum_msat: None,
3431 fn last_hops_with_public_channel_test() {
3432 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3433 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3434 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3435 let scorer = test_utils::TestScorer::with_penalty(0);
3436 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3437 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3438 // This test shows that public routes can be present in the invoice
3439 // which would be handled in the same manner.
3441 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3442 assert_eq!(route.paths[0].len(), 5);
3444 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3445 assert_eq!(route.paths[0][0].short_channel_id, 2);
3446 assert_eq!(route.paths[0][0].fee_msat, 100);
3447 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3448 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3449 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3451 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3452 assert_eq!(route.paths[0][1].short_channel_id, 4);
3453 assert_eq!(route.paths[0][1].fee_msat, 0);
3454 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3455 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3456 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3458 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3459 assert_eq!(route.paths[0][2].short_channel_id, 6);
3460 assert_eq!(route.paths[0][2].fee_msat, 0);
3461 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3462 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3463 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3465 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3466 assert_eq!(route.paths[0][3].short_channel_id, 11);
3467 assert_eq!(route.paths[0][3].fee_msat, 0);
3468 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3469 // If we have a peer in the node map, we'll use their features here since we don't have
3470 // a way of figuring out their features from the invoice:
3471 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3472 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3474 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3475 assert_eq!(route.paths[0][4].short_channel_id, 8);
3476 assert_eq!(route.paths[0][4].fee_msat, 100);
3477 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3478 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3479 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3483 fn our_chans_last_hop_connect_test() {
3484 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3485 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3486 let scorer = test_utils::TestScorer::with_penalty(0);
3487 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3488 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3490 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3491 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3492 let mut last_hops = last_hops(&nodes);
3493 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3494 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();
3495 assert_eq!(route.paths[0].len(), 2);
3497 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3498 assert_eq!(route.paths[0][0].short_channel_id, 42);
3499 assert_eq!(route.paths[0][0].fee_msat, 0);
3500 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3501 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3502 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3504 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3505 assert_eq!(route.paths[0][1].short_channel_id, 8);
3506 assert_eq!(route.paths[0][1].fee_msat, 100);
3507 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3508 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3509 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3511 last_hops[0].0[0].fees.base_msat = 1000;
3513 // Revert to via 6 as the fee on 8 goes up
3514 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3515 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3516 assert_eq!(route.paths[0].len(), 4);
3518 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3519 assert_eq!(route.paths[0][0].short_channel_id, 2);
3520 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3521 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3522 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3523 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3525 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3526 assert_eq!(route.paths[0][1].short_channel_id, 4);
3527 assert_eq!(route.paths[0][1].fee_msat, 100);
3528 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3529 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3530 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3532 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3533 assert_eq!(route.paths[0][2].short_channel_id, 7);
3534 assert_eq!(route.paths[0][2].fee_msat, 0);
3535 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3536 // If we have a peer in the node map, we'll use their features here since we don't have
3537 // a way of figuring out their features from the invoice:
3538 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3539 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3541 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3542 assert_eq!(route.paths[0][3].short_channel_id, 10);
3543 assert_eq!(route.paths[0][3].fee_msat, 100);
3544 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3545 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3546 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3548 // ...but still use 8 for larger payments as 6 has a variable feerate
3549 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3550 assert_eq!(route.paths[0].len(), 5);
3552 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3553 assert_eq!(route.paths[0][0].short_channel_id, 2);
3554 assert_eq!(route.paths[0][0].fee_msat, 3000);
3555 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3556 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3557 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3559 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3560 assert_eq!(route.paths[0][1].short_channel_id, 4);
3561 assert_eq!(route.paths[0][1].fee_msat, 0);
3562 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3563 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3564 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3566 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3567 assert_eq!(route.paths[0][2].short_channel_id, 6);
3568 assert_eq!(route.paths[0][2].fee_msat, 0);
3569 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3570 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3571 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3573 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3574 assert_eq!(route.paths[0][3].short_channel_id, 11);
3575 assert_eq!(route.paths[0][3].fee_msat, 1000);
3576 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3577 // If we have a peer in the node map, we'll use their features here since we don't have
3578 // a way of figuring out their features from the invoice:
3579 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3580 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3582 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3583 assert_eq!(route.paths[0][4].short_channel_id, 8);
3584 assert_eq!(route.paths[0][4].fee_msat, 2000);
3585 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3586 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3587 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3590 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> {
3591 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3592 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3593 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3595 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3596 let last_hops = RouteHint(vec![RouteHintHop {
3597 src_node_id: middle_node_id,
3598 short_channel_id: 8,
3601 proportional_millionths: last_hop_fee_prop,
3603 cltv_expiry_delta: (8 << 4) | 1,
3604 htlc_minimum_msat: None,
3605 htlc_maximum_msat: last_hop_htlc_max,
3607 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3608 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3609 let scorer = test_utils::TestScorer::with_penalty(0);
3610 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3611 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3612 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
3613 let logger = test_utils::TestLogger::new();
3614 let network_graph = NetworkGraph::new(genesis_hash, &logger);
3615 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3616 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
3621 fn unannounced_path_test() {
3622 // We should be able to send a payment to a destination without any help of a routing graph
3623 // if we have a channel with a common counterparty that appears in the first and last hop
3625 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3627 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3628 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3629 assert_eq!(route.paths[0].len(), 2);
3631 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3632 assert_eq!(route.paths[0][0].short_channel_id, 42);
3633 assert_eq!(route.paths[0][0].fee_msat, 1001);
3634 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3635 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3636 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3638 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3639 assert_eq!(route.paths[0][1].short_channel_id, 8);
3640 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3641 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3642 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3643 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3647 fn overflow_unannounced_path_test_liquidity_underflow() {
3648 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3649 // the last-hop had a fee which overflowed a u64, we'd panic.
3650 // This was due to us adding the first-hop from us unconditionally, causing us to think
3651 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3652 // In this test, we previously hit a subtraction underflow due to having less available
3653 // liquidity at the last hop than 0.
3654 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());
3658 fn overflow_unannounced_path_test_feerate_overflow() {
3659 // This tests for the same case as above, except instead of hitting a subtraction
3660 // underflow, we hit a case where the fee charged at a hop overflowed.
3661 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());
3665 fn available_amount_while_routing_test() {
3666 // Tests whether we choose the correct available channel amount while routing.
3668 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3669 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3670 let scorer = test_utils::TestScorer::with_penalty(0);
3671 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3672 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3673 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3675 // We will use a simple single-path route from
3676 // our node to node2 via node0: channels {1, 3}.
3678 // First disable all other paths.
3679 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3680 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3681 short_channel_id: 2,
3684 cltv_expiry_delta: 0,
3685 htlc_minimum_msat: 0,
3686 htlc_maximum_msat: OptionalField::Present(100_000),
3688 fee_proportional_millionths: 0,
3689 excess_data: Vec::new()
3691 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3692 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3693 short_channel_id: 12,
3696 cltv_expiry_delta: 0,
3697 htlc_minimum_msat: 0,
3698 htlc_maximum_msat: OptionalField::Present(100_000),
3700 fee_proportional_millionths: 0,
3701 excess_data: Vec::new()
3704 // Make the first channel (#1) very permissive,
3705 // and we will be testing all limits on the second channel.
3706 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3707 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3708 short_channel_id: 1,
3711 cltv_expiry_delta: 0,
3712 htlc_minimum_msat: 0,
3713 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3715 fee_proportional_millionths: 0,
3716 excess_data: Vec::new()
3719 // First, let's see if routing works if we have absolutely no idea about the available amount.
3720 // In this case, it should be set to 250_000 sats.
3721 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3722 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3723 short_channel_id: 3,
3726 cltv_expiry_delta: 0,
3727 htlc_minimum_msat: 0,
3728 htlc_maximum_msat: OptionalField::Absent,
3730 fee_proportional_millionths: 0,
3731 excess_data: Vec::new()
3735 // Attempt to route more than available results in a failure.
3736 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3737 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3738 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3739 } else { panic!(); }
3743 // Now, attempt to route an exact amount we have should be fine.
3744 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();
3745 assert_eq!(route.paths.len(), 1);
3746 let path = route.paths.last().unwrap();
3747 assert_eq!(path.len(), 2);
3748 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3749 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3752 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3753 // Disable channel #1 and use another first hop.
3754 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3755 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3756 short_channel_id: 1,
3759 cltv_expiry_delta: 0,
3760 htlc_minimum_msat: 0,
3761 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3763 fee_proportional_millionths: 0,
3764 excess_data: Vec::new()
3767 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3768 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3771 // Attempt to route more than available results in a failure.
3772 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3773 &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) {
3774 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3775 } else { panic!(); }
3779 // Now, attempt to route an exact amount we have should be fine.
3780 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();
3781 assert_eq!(route.paths.len(), 1);
3782 let path = route.paths.last().unwrap();
3783 assert_eq!(path.len(), 2);
3784 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3785 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3788 // Enable channel #1 back.
3789 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3790 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3791 short_channel_id: 1,
3794 cltv_expiry_delta: 0,
3795 htlc_minimum_msat: 0,
3796 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3798 fee_proportional_millionths: 0,
3799 excess_data: Vec::new()
3803 // Now let's see if routing works if we know only htlc_maximum_msat.
3804 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3805 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3806 short_channel_id: 3,
3809 cltv_expiry_delta: 0,
3810 htlc_minimum_msat: 0,
3811 htlc_maximum_msat: OptionalField::Present(15_000),
3813 fee_proportional_millionths: 0,
3814 excess_data: Vec::new()
3818 // Attempt to route more than available results in a failure.
3819 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3820 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3821 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3822 } else { panic!(); }
3826 // Now, attempt to route an exact amount we have should be fine.
3827 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3828 assert_eq!(route.paths.len(), 1);
3829 let path = route.paths.last().unwrap();
3830 assert_eq!(path.len(), 2);
3831 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3832 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3835 // Now let's see if routing works if we know only capacity from the UTXO.
3837 // We can't change UTXO capacity on the fly, so we'll disable
3838 // the existing channel and add another one with the capacity we need.
3839 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3840 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3841 short_channel_id: 3,
3844 cltv_expiry_delta: 0,
3845 htlc_minimum_msat: 0,
3846 htlc_maximum_msat: OptionalField::Absent,
3848 fee_proportional_millionths: 0,
3849 excess_data: Vec::new()
3852 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3853 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3854 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3855 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3856 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3858 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3859 gossip_sync.add_chain_access(Some(chain_monitor));
3861 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3862 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3863 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3864 short_channel_id: 333,
3867 cltv_expiry_delta: (3 << 4) | 1,
3868 htlc_minimum_msat: 0,
3869 htlc_maximum_msat: OptionalField::Absent,
3871 fee_proportional_millionths: 0,
3872 excess_data: Vec::new()
3874 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3875 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3876 short_channel_id: 333,
3879 cltv_expiry_delta: (3 << 4) | 2,
3880 htlc_minimum_msat: 0,
3881 htlc_maximum_msat: OptionalField::Absent,
3883 fee_proportional_millionths: 0,
3884 excess_data: Vec::new()
3888 // Attempt to route more than available results in a failure.
3889 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3890 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3891 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3892 } else { panic!(); }
3896 // Now, attempt to route an exact amount we have should be fine.
3897 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3898 assert_eq!(route.paths.len(), 1);
3899 let path = route.paths.last().unwrap();
3900 assert_eq!(path.len(), 2);
3901 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3902 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3905 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3906 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3907 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3908 short_channel_id: 333,
3911 cltv_expiry_delta: 0,
3912 htlc_minimum_msat: 0,
3913 htlc_maximum_msat: OptionalField::Present(10_000),
3915 fee_proportional_millionths: 0,
3916 excess_data: Vec::new()
3920 // Attempt to route more than available results in a failure.
3921 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3922 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3923 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3924 } else { panic!(); }
3928 // Now, attempt to route an exact amount we have should be fine.
3929 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3930 assert_eq!(route.paths.len(), 1);
3931 let path = route.paths.last().unwrap();
3932 assert_eq!(path.len(), 2);
3933 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3934 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3939 fn available_liquidity_last_hop_test() {
3940 // Check that available liquidity properly limits the path even when only
3941 // one of the latter hops is limited.
3942 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3943 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3944 let scorer = test_utils::TestScorer::with_penalty(0);
3945 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3946 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3947 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3949 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3950 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3951 // Total capacity: 50 sats.
3953 // Disable other potential paths.
3954 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3955 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3956 short_channel_id: 2,
3959 cltv_expiry_delta: 0,
3960 htlc_minimum_msat: 0,
3961 htlc_maximum_msat: OptionalField::Present(100_000),
3963 fee_proportional_millionths: 0,
3964 excess_data: Vec::new()
3966 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3967 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3968 short_channel_id: 7,
3971 cltv_expiry_delta: 0,
3972 htlc_minimum_msat: 0,
3973 htlc_maximum_msat: OptionalField::Present(100_000),
3975 fee_proportional_millionths: 0,
3976 excess_data: Vec::new()
3981 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3982 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3983 short_channel_id: 12,
3986 cltv_expiry_delta: 0,
3987 htlc_minimum_msat: 0,
3988 htlc_maximum_msat: OptionalField::Present(100_000),
3990 fee_proportional_millionths: 0,
3991 excess_data: Vec::new()
3993 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3994 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3995 short_channel_id: 13,
3998 cltv_expiry_delta: 0,
3999 htlc_minimum_msat: 0,
4000 htlc_maximum_msat: OptionalField::Present(100_000),
4002 fee_proportional_millionths: 0,
4003 excess_data: Vec::new()
4006 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4008 short_channel_id: 6,
4011 cltv_expiry_delta: 0,
4012 htlc_minimum_msat: 0,
4013 htlc_maximum_msat: OptionalField::Present(50_000),
4015 fee_proportional_millionths: 0,
4016 excess_data: Vec::new()
4018 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4019 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4020 short_channel_id: 11,
4023 cltv_expiry_delta: 0,
4024 htlc_minimum_msat: 0,
4025 htlc_maximum_msat: OptionalField::Present(100_000),
4027 fee_proportional_millionths: 0,
4028 excess_data: Vec::new()
4031 // Attempt to route more than available results in a failure.
4032 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4033 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4034 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4035 } else { panic!(); }
4039 // Now, attempt to route 49 sats (just a bit below the capacity).
4040 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4041 assert_eq!(route.paths.len(), 1);
4042 let mut total_amount_paid_msat = 0;
4043 for path in &route.paths {
4044 assert_eq!(path.len(), 4);
4045 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4046 total_amount_paid_msat += path.last().unwrap().fee_msat;
4048 assert_eq!(total_amount_paid_msat, 49_000);
4052 // Attempt to route an exact amount is also fine
4053 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4054 assert_eq!(route.paths.len(), 1);
4055 let mut total_amount_paid_msat = 0;
4056 for path in &route.paths {
4057 assert_eq!(path.len(), 4);
4058 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4059 total_amount_paid_msat += path.last().unwrap().fee_msat;
4061 assert_eq!(total_amount_paid_msat, 50_000);
4066 fn ignore_fee_first_hop_test() {
4067 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4068 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4069 let scorer = test_utils::TestScorer::with_penalty(0);
4070 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4071 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4072 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4074 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4075 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4076 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4077 short_channel_id: 1,
4080 cltv_expiry_delta: 0,
4081 htlc_minimum_msat: 0,
4082 htlc_maximum_msat: OptionalField::Present(100_000),
4083 fee_base_msat: 1_000_000,
4084 fee_proportional_millionths: 0,
4085 excess_data: Vec::new()
4087 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4088 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4089 short_channel_id: 3,
4092 cltv_expiry_delta: 0,
4093 htlc_minimum_msat: 0,
4094 htlc_maximum_msat: OptionalField::Present(50_000),
4096 fee_proportional_millionths: 0,
4097 excess_data: Vec::new()
4101 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4102 assert_eq!(route.paths.len(), 1);
4103 let mut total_amount_paid_msat = 0;
4104 for path in &route.paths {
4105 assert_eq!(path.len(), 2);
4106 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4107 total_amount_paid_msat += path.last().unwrap().fee_msat;
4109 assert_eq!(total_amount_paid_msat, 50_000);
4114 fn simple_mpp_route_test() {
4115 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4116 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4117 let scorer = test_utils::TestScorer::with_penalty(0);
4118 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4119 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4120 let payment_params = PaymentParameters::from_node_id(nodes[2])
4121 .with_features(InvoiceFeatures::known());
4123 // We need a route consisting of 3 paths:
4124 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4125 // To achieve this, the amount being transferred should be around
4126 // the total capacity of these 3 paths.
4128 // First, we set limits on these (previously unlimited) channels.
4129 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4131 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4132 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4133 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4134 short_channel_id: 1,
4137 cltv_expiry_delta: 0,
4138 htlc_minimum_msat: 0,
4139 htlc_maximum_msat: OptionalField::Present(100_000),
4141 fee_proportional_millionths: 0,
4142 excess_data: Vec::new()
4144 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4145 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4146 short_channel_id: 3,
4149 cltv_expiry_delta: 0,
4150 htlc_minimum_msat: 0,
4151 htlc_maximum_msat: OptionalField::Present(50_000),
4153 fee_proportional_millionths: 0,
4154 excess_data: Vec::new()
4157 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4158 // (total limit 60).
4159 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4160 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4161 short_channel_id: 12,
4164 cltv_expiry_delta: 0,
4165 htlc_minimum_msat: 0,
4166 htlc_maximum_msat: OptionalField::Present(60_000),
4168 fee_proportional_millionths: 0,
4169 excess_data: Vec::new()
4171 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4172 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4173 short_channel_id: 13,
4176 cltv_expiry_delta: 0,
4177 htlc_minimum_msat: 0,
4178 htlc_maximum_msat: OptionalField::Present(60_000),
4180 fee_proportional_millionths: 0,
4181 excess_data: Vec::new()
4184 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4185 // (total capacity 180 sats).
4186 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4187 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4188 short_channel_id: 2,
4191 cltv_expiry_delta: 0,
4192 htlc_minimum_msat: 0,
4193 htlc_maximum_msat: OptionalField::Present(200_000),
4195 fee_proportional_millionths: 0,
4196 excess_data: Vec::new()
4198 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4199 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4200 short_channel_id: 4,
4203 cltv_expiry_delta: 0,
4204 htlc_minimum_msat: 0,
4205 htlc_maximum_msat: OptionalField::Present(180_000),
4207 fee_proportional_millionths: 0,
4208 excess_data: Vec::new()
4212 // Attempt to route more than available results in a failure.
4213 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4214 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42,
4215 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4216 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4217 } else { panic!(); }
4221 // Attempt to route while setting max_path_count to 0 results in a failure.
4222 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4223 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4224 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100, 42,
4225 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4226 assert_eq!(err, "Can't find a route with no paths allowed.");
4227 } else { panic!(); }
4231 // Attempt to route while setting max_path_count to 3 results in a failure.
4232 // This is the case because the minimal_value_contribution_msat would require each path
4233 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4234 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4235 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4236 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000, 42,
4237 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4238 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4239 } else { panic!(); }
4243 // Now, attempt to route 250 sats (just a bit below the capacity).
4244 // Our algorithm should provide us with these 3 paths.
4245 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4246 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4247 assert_eq!(route.paths.len(), 3);
4248 let mut total_amount_paid_msat = 0;
4249 for path in &route.paths {
4250 assert_eq!(path.len(), 2);
4251 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4252 total_amount_paid_msat += path.last().unwrap().fee_msat;
4254 assert_eq!(total_amount_paid_msat, 250_000);
4258 // Attempt to route an exact amount is also fine
4259 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4260 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4261 assert_eq!(route.paths.len(), 3);
4262 let mut total_amount_paid_msat = 0;
4263 for path in &route.paths {
4264 assert_eq!(path.len(), 2);
4265 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4266 total_amount_paid_msat += path.last().unwrap().fee_msat;
4268 assert_eq!(total_amount_paid_msat, 290_000);
4273 fn long_mpp_route_test() {
4274 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4275 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4276 let scorer = test_utils::TestScorer::with_penalty(0);
4277 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4278 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4279 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4281 // We need a route consisting of 3 paths:
4282 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4283 // Note that these paths overlap (channels 5, 12, 13).
4284 // We will route 300 sats.
4285 // Each path will have 100 sats capacity, those channels which
4286 // are used twice will have 200 sats capacity.
4288 // Disable other potential paths.
4289 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4290 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4291 short_channel_id: 2,
4294 cltv_expiry_delta: 0,
4295 htlc_minimum_msat: 0,
4296 htlc_maximum_msat: OptionalField::Present(100_000),
4298 fee_proportional_millionths: 0,
4299 excess_data: Vec::new()
4301 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4303 short_channel_id: 7,
4306 cltv_expiry_delta: 0,
4307 htlc_minimum_msat: 0,
4308 htlc_maximum_msat: OptionalField::Present(100_000),
4310 fee_proportional_millionths: 0,
4311 excess_data: Vec::new()
4314 // Path via {node0, node2} is channels {1, 3, 5}.
4315 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4316 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4317 short_channel_id: 1,
4320 cltv_expiry_delta: 0,
4321 htlc_minimum_msat: 0,
4322 htlc_maximum_msat: OptionalField::Present(100_000),
4324 fee_proportional_millionths: 0,
4325 excess_data: Vec::new()
4327 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4328 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4329 short_channel_id: 3,
4332 cltv_expiry_delta: 0,
4333 htlc_minimum_msat: 0,
4334 htlc_maximum_msat: OptionalField::Present(100_000),
4336 fee_proportional_millionths: 0,
4337 excess_data: Vec::new()
4340 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4341 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4342 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4343 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4344 short_channel_id: 5,
4347 cltv_expiry_delta: 0,
4348 htlc_minimum_msat: 0,
4349 htlc_maximum_msat: OptionalField::Present(200_000),
4351 fee_proportional_millionths: 0,
4352 excess_data: Vec::new()
4355 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4356 // Add 100 sats to the capacities of {12, 13}, because these channels
4357 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4358 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4359 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4360 short_channel_id: 12,
4363 cltv_expiry_delta: 0,
4364 htlc_minimum_msat: 0,
4365 htlc_maximum_msat: OptionalField::Present(200_000),
4367 fee_proportional_millionths: 0,
4368 excess_data: Vec::new()
4370 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4371 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4372 short_channel_id: 13,
4375 cltv_expiry_delta: 0,
4376 htlc_minimum_msat: 0,
4377 htlc_maximum_msat: OptionalField::Present(200_000),
4379 fee_proportional_millionths: 0,
4380 excess_data: Vec::new()
4383 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4384 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4385 short_channel_id: 6,
4388 cltv_expiry_delta: 0,
4389 htlc_minimum_msat: 0,
4390 htlc_maximum_msat: OptionalField::Present(100_000),
4392 fee_proportional_millionths: 0,
4393 excess_data: Vec::new()
4395 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4396 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4397 short_channel_id: 11,
4400 cltv_expiry_delta: 0,
4401 htlc_minimum_msat: 0,
4402 htlc_maximum_msat: OptionalField::Present(100_000),
4404 fee_proportional_millionths: 0,
4405 excess_data: Vec::new()
4408 // Path via {node7, node2} is channels {12, 13, 5}.
4409 // We already limited them to 200 sats (they are used twice for 100 sats).
4410 // Nothing to do here.
4413 // Attempt to route more than available results in a failure.
4414 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4415 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4416 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4417 } else { panic!(); }
4421 // Now, attempt to route 300 sats (exact amount we can route).
4422 // Our algorithm should provide us with these 3 paths, 100 sats each.
4423 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4424 assert_eq!(route.paths.len(), 3);
4426 let mut total_amount_paid_msat = 0;
4427 for path in &route.paths {
4428 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4429 total_amount_paid_msat += path.last().unwrap().fee_msat;
4431 assert_eq!(total_amount_paid_msat, 300_000);
4437 fn mpp_cheaper_route_test() {
4438 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4439 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4440 let scorer = test_utils::TestScorer::with_penalty(0);
4441 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4442 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4443 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4445 // This test checks that if we have two cheaper paths and one more expensive path,
4446 // so that liquidity-wise any 2 of 3 combination is sufficient,
4447 // two cheaper paths will be taken.
4448 // These paths have equal available liquidity.
4450 // We need a combination of 3 paths:
4451 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4452 // Note that these paths overlap (channels 5, 12, 13).
4453 // Each path will have 100 sats capacity, those channels which
4454 // are used twice will have 200 sats capacity.
4456 // Disable other potential paths.
4457 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4458 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4459 short_channel_id: 2,
4462 cltv_expiry_delta: 0,
4463 htlc_minimum_msat: 0,
4464 htlc_maximum_msat: OptionalField::Present(100_000),
4466 fee_proportional_millionths: 0,
4467 excess_data: Vec::new()
4469 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4471 short_channel_id: 7,
4474 cltv_expiry_delta: 0,
4475 htlc_minimum_msat: 0,
4476 htlc_maximum_msat: OptionalField::Present(100_000),
4478 fee_proportional_millionths: 0,
4479 excess_data: Vec::new()
4482 // Path via {node0, node2} is channels {1, 3, 5}.
4483 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4484 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4485 short_channel_id: 1,
4488 cltv_expiry_delta: 0,
4489 htlc_minimum_msat: 0,
4490 htlc_maximum_msat: OptionalField::Present(100_000),
4492 fee_proportional_millionths: 0,
4493 excess_data: Vec::new()
4495 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4496 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4497 short_channel_id: 3,
4500 cltv_expiry_delta: 0,
4501 htlc_minimum_msat: 0,
4502 htlc_maximum_msat: OptionalField::Present(100_000),
4504 fee_proportional_millionths: 0,
4505 excess_data: Vec::new()
4508 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4509 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4510 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4511 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4512 short_channel_id: 5,
4515 cltv_expiry_delta: 0,
4516 htlc_minimum_msat: 0,
4517 htlc_maximum_msat: OptionalField::Present(200_000),
4519 fee_proportional_millionths: 0,
4520 excess_data: Vec::new()
4523 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4524 // Add 100 sats to the capacities of {12, 13}, because these channels
4525 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4526 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4527 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4528 short_channel_id: 12,
4531 cltv_expiry_delta: 0,
4532 htlc_minimum_msat: 0,
4533 htlc_maximum_msat: OptionalField::Present(200_000),
4535 fee_proportional_millionths: 0,
4536 excess_data: Vec::new()
4538 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4539 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4540 short_channel_id: 13,
4543 cltv_expiry_delta: 0,
4544 htlc_minimum_msat: 0,
4545 htlc_maximum_msat: OptionalField::Present(200_000),
4547 fee_proportional_millionths: 0,
4548 excess_data: Vec::new()
4551 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4552 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4553 short_channel_id: 6,
4556 cltv_expiry_delta: 0,
4557 htlc_minimum_msat: 0,
4558 htlc_maximum_msat: OptionalField::Present(100_000),
4559 fee_base_msat: 1_000,
4560 fee_proportional_millionths: 0,
4561 excess_data: Vec::new()
4563 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4565 short_channel_id: 11,
4568 cltv_expiry_delta: 0,
4569 htlc_minimum_msat: 0,
4570 htlc_maximum_msat: OptionalField::Present(100_000),
4572 fee_proportional_millionths: 0,
4573 excess_data: Vec::new()
4576 // Path via {node7, node2} is channels {12, 13, 5}.
4577 // We already limited them to 200 sats (they are used twice for 100 sats).
4578 // Nothing to do here.
4581 // Now, attempt to route 180 sats.
4582 // Our algorithm should provide us with these 2 paths.
4583 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4584 assert_eq!(route.paths.len(), 2);
4586 let mut total_value_transferred_msat = 0;
4587 let mut total_paid_msat = 0;
4588 for path in &route.paths {
4589 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4590 total_value_transferred_msat += path.last().unwrap().fee_msat;
4592 total_paid_msat += hop.fee_msat;
4595 // If we paid fee, this would be higher.
4596 assert_eq!(total_value_transferred_msat, 180_000);
4597 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4598 assert_eq!(total_fees_paid, 0);
4603 fn fees_on_mpp_route_test() {
4604 // This test makes sure that MPP algorithm properly takes into account
4605 // fees charged on the channels, by making the fees impactful:
4606 // if the fee is not properly accounted for, the behavior is different.
4607 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4608 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4609 let scorer = test_utils::TestScorer::with_penalty(0);
4610 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4611 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4612 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4614 // We need a route consisting of 2 paths:
4615 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4616 // We will route 200 sats, Each path will have 100 sats capacity.
4618 // This test is not particularly stable: e.g.,
4619 // there's a way to route via {node0, node2, node4}.
4620 // It works while pathfinding is deterministic, but can be broken otherwise.
4621 // It's fine to ignore this concern for now.
4623 // Disable other potential paths.
4624 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4625 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4626 short_channel_id: 2,
4629 cltv_expiry_delta: 0,
4630 htlc_minimum_msat: 0,
4631 htlc_maximum_msat: OptionalField::Present(100_000),
4633 fee_proportional_millionths: 0,
4634 excess_data: Vec::new()
4637 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4638 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4639 short_channel_id: 7,
4642 cltv_expiry_delta: 0,
4643 htlc_minimum_msat: 0,
4644 htlc_maximum_msat: OptionalField::Present(100_000),
4646 fee_proportional_millionths: 0,
4647 excess_data: Vec::new()
4650 // Path via {node0, node2} is channels {1, 3, 5}.
4651 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4652 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4653 short_channel_id: 1,
4656 cltv_expiry_delta: 0,
4657 htlc_minimum_msat: 0,
4658 htlc_maximum_msat: OptionalField::Present(100_000),
4660 fee_proportional_millionths: 0,
4661 excess_data: Vec::new()
4663 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4664 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4665 short_channel_id: 3,
4668 cltv_expiry_delta: 0,
4669 htlc_minimum_msat: 0,
4670 htlc_maximum_msat: OptionalField::Present(100_000),
4672 fee_proportional_millionths: 0,
4673 excess_data: Vec::new()
4676 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4677 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4678 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4679 short_channel_id: 5,
4682 cltv_expiry_delta: 0,
4683 htlc_minimum_msat: 0,
4684 htlc_maximum_msat: OptionalField::Present(100_000),
4686 fee_proportional_millionths: 0,
4687 excess_data: Vec::new()
4690 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4691 // All channels should be 100 sats capacity. But for the fee experiment,
4692 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4693 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4694 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4695 // so no matter how large are other channels,
4696 // the whole path will be limited by 100 sats with just these 2 conditions:
4697 // - channel 12 capacity is 250 sats
4698 // - fee for channel 6 is 150 sats
4699 // Let's test this by enforcing these 2 conditions and removing other limits.
4700 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4701 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4702 short_channel_id: 12,
4705 cltv_expiry_delta: 0,
4706 htlc_minimum_msat: 0,
4707 htlc_maximum_msat: OptionalField::Present(250_000),
4709 fee_proportional_millionths: 0,
4710 excess_data: Vec::new()
4712 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4713 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4714 short_channel_id: 13,
4717 cltv_expiry_delta: 0,
4718 htlc_minimum_msat: 0,
4719 htlc_maximum_msat: OptionalField::Absent,
4721 fee_proportional_millionths: 0,
4722 excess_data: Vec::new()
4725 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4726 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4727 short_channel_id: 6,
4730 cltv_expiry_delta: 0,
4731 htlc_minimum_msat: 0,
4732 htlc_maximum_msat: OptionalField::Absent,
4733 fee_base_msat: 150_000,
4734 fee_proportional_millionths: 0,
4735 excess_data: Vec::new()
4737 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4738 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4739 short_channel_id: 11,
4742 cltv_expiry_delta: 0,
4743 htlc_minimum_msat: 0,
4744 htlc_maximum_msat: OptionalField::Absent,
4746 fee_proportional_millionths: 0,
4747 excess_data: Vec::new()
4751 // Attempt to route more than available results in a failure.
4752 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4753 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4754 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4755 } else { panic!(); }
4759 // Now, attempt to route 200 sats (exact amount we can route).
4760 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4761 assert_eq!(route.paths.len(), 2);
4763 let mut total_amount_paid_msat = 0;
4764 for path in &route.paths {
4765 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4766 total_amount_paid_msat += path.last().unwrap().fee_msat;
4768 assert_eq!(total_amount_paid_msat, 200_000);
4769 assert_eq!(route.get_total_fees(), 150_000);
4774 fn mpp_with_last_hops() {
4775 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4776 // via a single last-hop route hint, we'd fail to route if we first collected routes
4777 // totaling close but not quite enough to fund the full payment.
4779 // This was because we considered last-hop hints to have exactly the sought payment amount
4780 // instead of the amount we were trying to collect, needlessly limiting our path searching
4781 // at the very first hop.
4783 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4784 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4785 // to only have the remaining to-collect amount in available liquidity.
4787 // This bug appeared in production in some specific channel configurations.
4788 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4789 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4790 let scorer = test_utils::TestScorer::with_penalty(0);
4791 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4792 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4793 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4794 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4795 src_node_id: nodes[2],
4796 short_channel_id: 42,
4797 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4798 cltv_expiry_delta: 42,
4799 htlc_minimum_msat: None,
4800 htlc_maximum_msat: None,
4803 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4804 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4805 // would first use the no-fee route and then fail to find a path along the second route as
4806 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4807 // under 5% of our payment amount.
4808 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4809 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4810 short_channel_id: 1,
4813 cltv_expiry_delta: (5 << 4) | 5,
4814 htlc_minimum_msat: 0,
4815 htlc_maximum_msat: OptionalField::Present(99_000),
4816 fee_base_msat: u32::max_value(),
4817 fee_proportional_millionths: u32::max_value(),
4818 excess_data: Vec::new()
4820 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4821 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4822 short_channel_id: 2,
4825 cltv_expiry_delta: (5 << 4) | 3,
4826 htlc_minimum_msat: 0,
4827 htlc_maximum_msat: OptionalField::Present(99_000),
4828 fee_base_msat: u32::max_value(),
4829 fee_proportional_millionths: u32::max_value(),
4830 excess_data: Vec::new()
4832 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4833 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4834 short_channel_id: 4,
4837 cltv_expiry_delta: (4 << 4) | 1,
4838 htlc_minimum_msat: 0,
4839 htlc_maximum_msat: OptionalField::Absent,
4841 fee_proportional_millionths: 0,
4842 excess_data: Vec::new()
4844 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4845 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4846 short_channel_id: 13,
4848 flags: 0|2, // Channel disabled
4849 cltv_expiry_delta: (13 << 4) | 1,
4850 htlc_minimum_msat: 0,
4851 htlc_maximum_msat: OptionalField::Absent,
4853 fee_proportional_millionths: 2000000,
4854 excess_data: Vec::new()
4857 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4859 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();
4860 assert_eq!(route.paths.len(), 2);
4861 route.paths.sort_by_key(|path| path[0].short_channel_id);
4862 // Paths are manually ordered ordered by SCID, so:
4863 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4864 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4865 assert_eq!(route.paths[0][0].short_channel_id, 1);
4866 assert_eq!(route.paths[0][0].fee_msat, 0);
4867 assert_eq!(route.paths[0][2].fee_msat, 99_000);
4868 assert_eq!(route.paths[1][0].short_channel_id, 2);
4869 assert_eq!(route.paths[1][0].fee_msat, 1);
4870 assert_eq!(route.paths[1][2].fee_msat, 1_000);
4871 assert_eq!(route.get_total_fees(), 1);
4872 assert_eq!(route.get_total_amount(), 100_000);
4876 fn drop_lowest_channel_mpp_route_test() {
4877 // This test checks that low-capacity channel is dropped when after
4878 // path finding we realize that we found more capacity than we need.
4879 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4880 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4881 let scorer = test_utils::TestScorer::with_penalty(0);
4882 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4883 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4884 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known())
4885 .with_max_channel_saturation_power_of_half(0);
4887 // We need a route consisting of 3 paths:
4888 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4890 // The first and the second paths should be sufficient, but the third should be
4891 // cheaper, so that we select it but drop later.
4893 // First, we set limits on these (previously unlimited) channels.
4894 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4896 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4897 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4898 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4899 short_channel_id: 1,
4902 cltv_expiry_delta: 0,
4903 htlc_minimum_msat: 0,
4904 htlc_maximum_msat: OptionalField::Present(100_000),
4906 fee_proportional_millionths: 0,
4907 excess_data: Vec::new()
4909 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4910 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4911 short_channel_id: 3,
4914 cltv_expiry_delta: 0,
4915 htlc_minimum_msat: 0,
4916 htlc_maximum_msat: OptionalField::Present(50_000),
4918 fee_proportional_millionths: 0,
4919 excess_data: Vec::new()
4922 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4923 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4924 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4925 short_channel_id: 12,
4928 cltv_expiry_delta: 0,
4929 htlc_minimum_msat: 0,
4930 htlc_maximum_msat: OptionalField::Present(60_000),
4932 fee_proportional_millionths: 0,
4933 excess_data: Vec::new()
4935 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4936 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4937 short_channel_id: 13,
4940 cltv_expiry_delta: 0,
4941 htlc_minimum_msat: 0,
4942 htlc_maximum_msat: OptionalField::Present(60_000),
4944 fee_proportional_millionths: 0,
4945 excess_data: Vec::new()
4948 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4949 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4950 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4951 short_channel_id: 2,
4954 cltv_expiry_delta: 0,
4955 htlc_minimum_msat: 0,
4956 htlc_maximum_msat: OptionalField::Present(20_000),
4958 fee_proportional_millionths: 0,
4959 excess_data: Vec::new()
4961 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4962 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4963 short_channel_id: 4,
4966 cltv_expiry_delta: 0,
4967 htlc_minimum_msat: 0,
4968 htlc_maximum_msat: OptionalField::Present(20_000),
4970 fee_proportional_millionths: 0,
4971 excess_data: Vec::new()
4975 // Attempt to route more than available results in a failure.
4976 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4977 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4978 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4979 } else { panic!(); }
4983 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4984 // Our algorithm should provide us with these 3 paths.
4985 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4986 assert_eq!(route.paths.len(), 3);
4987 let mut total_amount_paid_msat = 0;
4988 for path in &route.paths {
4989 assert_eq!(path.len(), 2);
4990 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4991 total_amount_paid_msat += path.last().unwrap().fee_msat;
4993 assert_eq!(total_amount_paid_msat, 125_000);
4997 // Attempt to route without the last small cheap channel
4998 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4999 assert_eq!(route.paths.len(), 2);
5000 let mut total_amount_paid_msat = 0;
5001 for path in &route.paths {
5002 assert_eq!(path.len(), 2);
5003 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
5004 total_amount_paid_msat += path.last().unwrap().fee_msat;
5006 assert_eq!(total_amount_paid_msat, 90_000);
5011 fn min_criteria_consistency() {
5012 // Test that we don't use an inconsistent metric between updating and walking nodes during
5013 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
5014 // was updated with a different criterion from the heap sorting, resulting in loops in
5015 // calculated paths. We test for that specific case here.
5017 // We construct a network that looks like this:
5019 // node2 -1(3)2- node3
5023 // node1 -1(5)2- node4 -1(1)2- node6
5029 // We create a loop on the side of our real path - our destination is node 6, with a
5030 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
5031 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
5032 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
5033 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
5034 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
5035 // "previous hop" being set to node 3, creating a loop in the path.
5036 let secp_ctx = Secp256k1::new();
5037 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
5038 let logger = Arc::new(test_utils::TestLogger::new());
5039 let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
5040 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5041 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5042 let scorer = test_utils::TestScorer::with_penalty(0);
5043 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5044 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5045 let payment_params = PaymentParameters::from_node_id(nodes[6]);
5047 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5048 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5049 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5050 short_channel_id: 6,
5053 cltv_expiry_delta: (6 << 4) | 0,
5054 htlc_minimum_msat: 0,
5055 htlc_maximum_msat: OptionalField::Absent,
5057 fee_proportional_millionths: 0,
5058 excess_data: Vec::new()
5060 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5062 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5063 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5064 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5065 short_channel_id: 5,
5068 cltv_expiry_delta: (5 << 4) | 0,
5069 htlc_minimum_msat: 0,
5070 htlc_maximum_msat: OptionalField::Absent,
5072 fee_proportional_millionths: 0,
5073 excess_data: Vec::new()
5075 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5077 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5078 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5079 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5080 short_channel_id: 4,
5083 cltv_expiry_delta: (4 << 4) | 0,
5084 htlc_minimum_msat: 0,
5085 htlc_maximum_msat: OptionalField::Absent,
5087 fee_proportional_millionths: 0,
5088 excess_data: Vec::new()
5090 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5092 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5093 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5094 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5095 short_channel_id: 3,
5098 cltv_expiry_delta: (3 << 4) | 0,
5099 htlc_minimum_msat: 0,
5100 htlc_maximum_msat: OptionalField::Absent,
5102 fee_proportional_millionths: 0,
5103 excess_data: Vec::new()
5105 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5107 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5108 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5109 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5110 short_channel_id: 2,
5113 cltv_expiry_delta: (2 << 4) | 0,
5114 htlc_minimum_msat: 0,
5115 htlc_maximum_msat: OptionalField::Absent,
5117 fee_proportional_millionths: 0,
5118 excess_data: Vec::new()
5121 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5122 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5123 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5124 short_channel_id: 1,
5127 cltv_expiry_delta: (1 << 4) | 0,
5128 htlc_minimum_msat: 100,
5129 htlc_maximum_msat: OptionalField::Absent,
5131 fee_proportional_millionths: 0,
5132 excess_data: Vec::new()
5134 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5137 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5138 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5139 assert_eq!(route.paths.len(), 1);
5140 assert_eq!(route.paths[0].len(), 3);
5142 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
5143 assert_eq!(route.paths[0][0].short_channel_id, 6);
5144 assert_eq!(route.paths[0][0].fee_msat, 100);
5145 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
5146 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
5147 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
5149 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
5150 assert_eq!(route.paths[0][1].short_channel_id, 5);
5151 assert_eq!(route.paths[0][1].fee_msat, 0);
5152 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
5153 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
5154 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
5156 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
5157 assert_eq!(route.paths[0][2].short_channel_id, 1);
5158 assert_eq!(route.paths[0][2].fee_msat, 10_000);
5159 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
5160 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
5161 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
5167 fn exact_fee_liquidity_limit() {
5168 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5169 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5170 // we calculated fees on a higher value, resulting in us ignoring such paths.
5171 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5172 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5173 let scorer = test_utils::TestScorer::with_penalty(0);
5174 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5175 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5176 let payment_params = PaymentParameters::from_node_id(nodes[2]);
5178 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5180 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5181 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5182 short_channel_id: 2,
5185 cltv_expiry_delta: 0,
5186 htlc_minimum_msat: 0,
5187 htlc_maximum_msat: OptionalField::Present(85_000),
5189 fee_proportional_millionths: 0,
5190 excess_data: Vec::new()
5193 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5194 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5195 short_channel_id: 12,
5198 cltv_expiry_delta: (4 << 4) | 1,
5199 htlc_minimum_msat: 0,
5200 htlc_maximum_msat: OptionalField::Present(270_000),
5202 fee_proportional_millionths: 1000000,
5203 excess_data: Vec::new()
5207 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5208 // 200% fee charged channel 13 in the 1-to-2 direction.
5209 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5210 assert_eq!(route.paths.len(), 1);
5211 assert_eq!(route.paths[0].len(), 2);
5213 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
5214 assert_eq!(route.paths[0][0].short_channel_id, 12);
5215 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
5216 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
5217 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
5218 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
5220 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
5221 assert_eq!(route.paths[0][1].short_channel_id, 13);
5222 assert_eq!(route.paths[0][1].fee_msat, 90_000);
5223 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
5224 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
5225 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
5230 fn htlc_max_reduction_below_min() {
5231 // Test that if, while walking the graph, we reduce the value being sent to meet an
5232 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5233 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5234 // resulting in us thinking there is no possible path, even if other paths exist.
5235 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5236 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5237 let scorer = test_utils::TestScorer::with_penalty(0);
5238 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5239 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5240 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
5242 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5243 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5244 // then try to send 90_000.
5245 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5246 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5247 short_channel_id: 2,
5250 cltv_expiry_delta: 0,
5251 htlc_minimum_msat: 0,
5252 htlc_maximum_msat: OptionalField::Present(80_000),
5254 fee_proportional_millionths: 0,
5255 excess_data: Vec::new()
5257 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5258 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5259 short_channel_id: 4,
5262 cltv_expiry_delta: (4 << 4) | 1,
5263 htlc_minimum_msat: 90_000,
5264 htlc_maximum_msat: OptionalField::Absent,
5266 fee_proportional_millionths: 0,
5267 excess_data: Vec::new()
5271 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5272 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5273 // expensive) channels 12-13 path.
5274 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5275 assert_eq!(route.paths.len(), 1);
5276 assert_eq!(route.paths[0].len(), 2);
5278 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
5279 assert_eq!(route.paths[0][0].short_channel_id, 12);
5280 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
5281 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
5282 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
5283 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
5285 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
5286 assert_eq!(route.paths[0][1].short_channel_id, 13);
5287 assert_eq!(route.paths[0][1].fee_msat, 90_000);
5288 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
5289 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
5290 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
5295 fn multiple_direct_first_hops() {
5296 // Previously we'd only ever considered one first hop path per counterparty.
5297 // However, as we don't restrict users to one channel per peer, we really need to support
5298 // looking at all first hop paths.
5299 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5300 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5301 // route over multiple channels with the same first hop.
5302 let secp_ctx = Secp256k1::new();
5303 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5304 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
5305 let logger = Arc::new(test_utils::TestLogger::new());
5306 let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
5307 let scorer = test_utils::TestScorer::with_penalty(0);
5308 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
5309 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5310 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5313 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5314 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
5315 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
5316 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5317 assert_eq!(route.paths.len(), 1);
5318 assert_eq!(route.paths[0].len(), 1);
5320 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5321 assert_eq!(route.paths[0][0].short_channel_id, 3);
5322 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5325 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5326 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
5327 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
5328 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5329 assert_eq!(route.paths.len(), 2);
5330 assert_eq!(route.paths[0].len(), 1);
5331 assert_eq!(route.paths[1].len(), 1);
5333 assert!((route.paths[0][0].short_channel_id == 3 && route.paths[1][0].short_channel_id == 2) ||
5334 (route.paths[0][0].short_channel_id == 2 && route.paths[1][0].short_channel_id == 3));
5336 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5337 assert_eq!(route.paths[0][0].fee_msat, 50_000);
5339 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
5340 assert_eq!(route.paths[1][0].fee_msat, 50_000);
5344 // If we have a bunch of outbound channels to the same node, where most are not
5345 // sufficient to pay the full payment, but one is, we should default to just using the
5346 // one single channel that has sufficient balance, avoiding MPP.
5348 // If we have several options above the 3xpayment value threshold, we should pick the
5349 // smallest of them, avoiding further fragmenting our available outbound balance to
5351 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5352 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
5353 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
5354 &get_channel_details(Some(5), nodes[0], InitFeatures::known(), 50_000),
5355 &get_channel_details(Some(6), nodes[0], InitFeatures::known(), 300_000),
5356 &get_channel_details(Some(7), nodes[0], InitFeatures::known(), 50_000),
5357 &get_channel_details(Some(8), nodes[0], InitFeatures::known(), 50_000),
5358 &get_channel_details(Some(9), nodes[0], InitFeatures::known(), 50_000),
5359 &get_channel_details(Some(4), nodes[0], InitFeatures::known(), 1_000_000),
5360 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5361 assert_eq!(route.paths.len(), 1);
5362 assert_eq!(route.paths[0].len(), 1);
5364 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5365 assert_eq!(route.paths[0][0].short_channel_id, 6);
5366 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5371 fn prefers_shorter_route_with_higher_fees() {
5372 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5373 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5374 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5376 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5377 let scorer = test_utils::TestScorer::with_penalty(0);
5378 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5379 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5380 let route = get_route(
5381 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5382 Arc::clone(&logger), &scorer, &random_seed_bytes
5384 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5386 assert_eq!(route.get_total_fees(), 100);
5387 assert_eq!(route.get_total_amount(), 100);
5388 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5390 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5391 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5392 let scorer = test_utils::TestScorer::with_penalty(100);
5393 let route = get_route(
5394 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5395 Arc::clone(&logger), &scorer, &random_seed_bytes
5397 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5399 assert_eq!(route.get_total_fees(), 300);
5400 assert_eq!(route.get_total_amount(), 100);
5401 assert_eq!(path, vec![2, 4, 7, 10]);
5404 struct BadChannelScorer {
5405 short_channel_id: u64,
5409 impl Writeable for BadChannelScorer {
5410 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5412 impl Score for BadChannelScorer {
5413 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage) -> u64 {
5414 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5417 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5418 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5419 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5420 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5423 struct BadNodeScorer {
5428 impl Writeable for BadNodeScorer {
5429 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5432 impl Score for BadNodeScorer {
5433 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage) -> u64 {
5434 if *target == self.node_id { u64::max_value() } else { 0 }
5437 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5438 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5439 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5440 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5444 fn avoids_routing_through_bad_channels_and_nodes() {
5445 let (secp_ctx, network, _, _, logger) = build_graph();
5446 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5447 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5448 let network_graph = network.read_only();
5450 // A path to nodes[6] exists when no penalties are applied to any channel.
5451 let scorer = test_utils::TestScorer::with_penalty(0);
5452 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5453 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5454 let route = get_route(
5455 &our_id, &payment_params, &network_graph, None, 100, 42,
5456 Arc::clone(&logger), &scorer, &random_seed_bytes
5458 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5460 assert_eq!(route.get_total_fees(), 100);
5461 assert_eq!(route.get_total_amount(), 100);
5462 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5464 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5465 let scorer = BadChannelScorer { short_channel_id: 6 };
5466 let route = get_route(
5467 &our_id, &payment_params, &network_graph, None, 100, 42,
5468 Arc::clone(&logger), &scorer, &random_seed_bytes
5470 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5472 assert_eq!(route.get_total_fees(), 300);
5473 assert_eq!(route.get_total_amount(), 100);
5474 assert_eq!(path, vec![2, 4, 7, 10]);
5476 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5477 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5479 &our_id, &payment_params, &network_graph, None, 100, 42,
5480 Arc::clone(&logger), &scorer, &random_seed_bytes
5482 Err(LightningError { err, .. } ) => {
5483 assert_eq!(err, "Failed to find a path to the given destination");
5485 Ok(_) => panic!("Expected error"),
5490 fn total_fees_single_path() {
5494 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5495 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5496 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5499 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5500 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5501 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5504 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5505 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5506 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5509 payment_params: None,
5512 assert_eq!(route.get_total_fees(), 250);
5513 assert_eq!(route.get_total_amount(), 225);
5517 fn total_fees_multi_path() {
5521 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5522 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5523 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5526 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5527 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5528 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5532 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5533 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5534 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5537 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5538 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5539 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5542 payment_params: None,
5545 assert_eq!(route.get_total_fees(), 200);
5546 assert_eq!(route.get_total_amount(), 300);
5550 fn total_empty_route_no_panic() {
5551 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5552 // would both panic if the route was completely empty. We test to ensure they return 0
5553 // here, even though its somewhat nonsensical as a route.
5554 let route = Route { paths: Vec::new(), payment_params: None };
5556 assert_eq!(route.get_total_fees(), 0);
5557 assert_eq!(route.get_total_amount(), 0);
5561 fn limits_total_cltv_delta() {
5562 let (secp_ctx, network, _, _, logger) = build_graph();
5563 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5564 let network_graph = network.read_only();
5566 let scorer = test_utils::TestScorer::with_penalty(0);
5568 // Make sure that generally there is at least one route available
5569 let feasible_max_total_cltv_delta = 1008;
5570 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5571 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5572 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5573 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5574 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5575 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5576 assert_ne!(path.len(), 0);
5578 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5579 let fail_max_total_cltv_delta = 23;
5580 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5581 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5582 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5584 Err(LightningError { err, .. } ) => {
5585 assert_eq!(err, "Failed to find a path to the given destination");
5587 Ok(_) => panic!("Expected error"),
5592 fn avoids_recently_failed_paths() {
5593 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5594 // randomly inserting channels into it until we can't find a route anymore.
5595 let (secp_ctx, network, _, _, logger) = build_graph();
5596 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5597 let network_graph = network.read_only();
5599 let scorer = test_utils::TestScorer::with_penalty(0);
5600 let mut payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5601 .with_max_path_count(1);
5602 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5603 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5605 // We should be able to find a route initially, and then after we fail a few random
5606 // channels eventually we won't be able to any longer.
5607 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).is_ok());
5609 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes) {
5610 for chan in route.paths[0].iter() {
5611 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5613 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5614 % route.paths[0].len();
5615 payment_params.previously_failed_channels.push(route.paths[0][victim].short_channel_id);
5621 fn limits_path_length() {
5622 let (secp_ctx, network, _, _, logger) = build_line_graph();
5623 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5624 let network_graph = network.read_only();
5626 let scorer = test_utils::TestScorer::with_penalty(0);
5627 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5628 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5630 // First check we can actually create a long route on this graph.
5631 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5632 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5633 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5634 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5635 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5637 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5638 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5639 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5640 Arc::clone(&logger), &scorer, &random_seed_bytes)
5642 Err(LightningError { err, .. } ) => {
5643 assert_eq!(err, "Failed to find a path to the given destination");
5645 Ok(_) => panic!("Expected error"),
5650 fn adds_and_limits_cltv_offset() {
5651 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5652 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5654 let scorer = test_utils::TestScorer::with_penalty(0);
5656 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5657 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5658 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5659 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5660 assert_eq!(route.paths.len(), 1);
5662 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5664 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5665 let mut route_default = route.clone();
5666 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5667 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5668 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5669 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5670 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5672 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5673 let mut route_limited = route.clone();
5674 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5675 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5676 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5677 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5678 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5682 fn adds_plausible_cltv_offset() {
5683 let (secp_ctx, network, _, _, logger) = build_graph();
5684 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5685 let network_graph = network.read_only();
5686 let network_nodes = network_graph.nodes();
5687 let network_channels = network_graph.channels();
5688 let scorer = test_utils::TestScorer::with_penalty(0);
5689 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5690 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5691 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5693 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5694 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5695 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5697 let mut path_plausibility = vec![];
5699 for p in route.paths {
5700 // 1. Select random observation point
5701 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5702 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5704 prng.process_in_place(&mut random_bytes);
5705 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5706 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5708 // 2. Calculate what CLTV expiry delta we would observe there
5709 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5711 // 3. Starting from the observation point, find candidate paths
5712 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5713 candidates.push_back((observation_point, vec![]));
5715 let mut found_plausible_candidate = false;
5717 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5718 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5719 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5720 found_plausible_candidate = true;
5721 break 'candidate_loop;
5725 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5726 for channel_id in &cur_node.channels {
5727 if let Some(channel_info) = network_channels.get(&channel_id) {
5728 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5729 if let Some(channel_update_info) = dir_info.direction() {
5730 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5731 if cur_path_cltv_deltas.iter().sum::<u32>()
5732 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5733 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5734 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5735 candidates.push_back((*next_id, new_path_cltv_deltas));
5744 path_plausibility.push(found_plausible_candidate);
5746 assert!(path_plausibility.iter().all(|x| *x));
5750 fn builds_correct_path_from_hops() {
5751 let (secp_ctx, network, _, _, logger) = build_graph();
5752 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5753 let network_graph = network.read_only();
5755 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5756 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5758 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5759 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5760 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5761 &network_graph, 100, 0, Arc::clone(&logger), &random_seed_bytes).unwrap();
5762 let route_hop_pubkeys = route.paths[0].iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5763 assert_eq!(hops.len(), route.paths[0].len());
5764 for (idx, hop_pubkey) in hops.iter().enumerate() {
5765 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5770 fn avoids_saturating_channels() {
5771 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5772 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5774 let scorer = ProbabilisticScorer::new(Default::default(), &*network_graph, Arc::clone(&logger));
5776 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5777 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5778 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5779 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5780 short_channel_id: 4,
5783 cltv_expiry_delta: (4 << 4) | 1,
5784 htlc_minimum_msat: 0,
5785 htlc_maximum_msat: OptionalField::Present(200_000_000),
5787 fee_proportional_millionths: 0,
5788 excess_data: Vec::new()
5790 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5791 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5792 short_channel_id: 13,
5795 cltv_expiry_delta: (13 << 4) | 1,
5796 htlc_minimum_msat: 0,
5797 htlc_maximum_msat: OptionalField::Present(200_000_000),
5799 fee_proportional_millionths: 0,
5800 excess_data: Vec::new()
5803 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
5804 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5805 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5806 // 150,000 sat is less than the available liquidity on each channel, set above.
5807 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 150_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5808 assert_eq!(route.paths.len(), 2);
5809 assert!((route.paths[0][1].short_channel_id == 4 && route.paths[1][1].short_channel_id == 13) ||
5810 (route.paths[1][1].short_channel_id == 4 && route.paths[0][1].short_channel_id == 13));
5813 #[cfg(not(feature = "no-std"))]
5814 pub(super) fn random_init_seed() -> u64 {
5815 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5816 use core::hash::{BuildHasher, Hasher};
5817 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5818 println!("Using seed of {}", seed);
5821 #[cfg(not(feature = "no-std"))]
5822 use util::ser::ReadableArgs;
5825 #[cfg(not(feature = "no-std"))]
5826 fn generate_routes() {
5827 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5829 let mut d = match super::test_utils::get_route_file() {
5836 let logger = test_utils::TestLogger::new();
5837 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5838 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5839 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5841 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5842 let mut seed = random_init_seed() as usize;
5843 let nodes = graph.read_only().nodes().clone();
5844 'load_endpoints: for _ in 0..10 {
5846 seed = seed.overflowing_mul(0xdeadbeef).0;
5847 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5848 seed = seed.overflowing_mul(0xdeadbeef).0;
5849 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5850 let payment_params = PaymentParameters::from_node_id(dst);
5851 let amt = seed as u64 % 200_000_000;
5852 let params = ProbabilisticScoringParameters::default();
5853 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5854 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5855 continue 'load_endpoints;
5862 #[cfg(not(feature = "no-std"))]
5863 fn generate_routes_mpp() {
5864 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5866 let mut d = match super::test_utils::get_route_file() {
5873 let logger = test_utils::TestLogger::new();
5874 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5875 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5876 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5878 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5879 let mut seed = random_init_seed() as usize;
5880 let nodes = graph.read_only().nodes().clone();
5881 'load_endpoints: for _ in 0..10 {
5883 seed = seed.overflowing_mul(0xdeadbeef).0;
5884 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5885 seed = seed.overflowing_mul(0xdeadbeef).0;
5886 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5887 let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
5888 let amt = seed as u64 % 200_000_000;
5889 let params = ProbabilisticScoringParameters::default();
5890 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5891 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5892 continue 'load_endpoints;
5899 fn honors_manual_penalties() {
5900 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5901 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5903 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5904 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5906 let scorer_params = ProbabilisticScoringParameters::default();
5907 let mut scorer = ProbabilisticScorer::new(scorer_params, Arc::clone(&network_graph), Arc::clone(&logger));
5909 // First check set manual penalties are returned by the scorer.
5910 let usage = ChannelUsage {
5912 inflight_htlc_msat: 0,
5913 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
5915 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5916 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5917 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage), 456);
5919 // Then check we can get a normal route
5920 let payment_params = PaymentParameters::from_node_id(nodes[10]);
5921 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5922 assert!(route.is_ok());
5924 // Then check that we can't get a route if we ban an intermediate node.
5925 scorer.add_banned(&NodeId::from_pubkey(&nodes[3]));
5926 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5927 assert!(route.is_err());
5929 // Finally make sure we can route again, when we remove the ban.
5930 scorer.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5931 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5932 assert!(route.is_ok());
5936 #[cfg(all(test, not(feature = "no-std")))]
5937 pub(crate) mod test_utils {
5939 /// Tries to open a network graph file, or panics with a URL to fetch it.
5940 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5941 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5942 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5943 .or_else(|_| { // Fall back to guessing based on the binary location
5944 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5945 let mut path = std::env::current_exe().unwrap();
5946 path.pop(); // lightning-...
5948 path.pop(); // debug
5949 path.pop(); // target
5950 path.push("lightning");
5951 path.push("net_graph-2021-05-31.bin");
5952 eprintln!("{}", path.to_str().unwrap());
5955 .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");
5956 #[cfg(require_route_graph_test)]
5957 return Ok(res.unwrap());
5958 #[cfg(not(require_route_graph_test))]
5963 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5966 use bitcoin::hashes::Hash;
5967 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5968 use chain::transaction::OutPoint;
5969 use chain::keysinterface::{KeysManager,KeysInterface};
5970 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
5971 use ln::features::{InitFeatures, InvoiceFeatures};
5972 use routing::gossip::NetworkGraph;
5973 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
5974 use util::logger::{Logger, Record};
5975 use util::ser::ReadableArgs;
5979 struct DummyLogger {}
5980 impl Logger for DummyLogger {
5981 fn log(&self, _record: &Record) {}
5984 fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
5985 let mut d = test_utils::get_route_file().unwrap();
5986 NetworkGraph::read(&mut d, logger).unwrap()
5989 fn payer_pubkey() -> PublicKey {
5990 let secp_ctx = Secp256k1::new();
5991 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5995 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5997 channel_id: [0; 32],
5998 counterparty: ChannelCounterparty {
5999 features: InitFeatures::known(),
6001 unspendable_punishment_reserve: 0,
6002 forwarding_info: None,
6003 outbound_htlc_minimum_msat: None,
6004 outbound_htlc_maximum_msat: None,
6006 funding_txo: Some(OutPoint {
6007 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
6010 short_channel_id: Some(1),
6011 inbound_scid_alias: None,
6012 outbound_scid_alias: None,
6013 channel_value_satoshis: 10_000_000,
6015 balance_msat: 10_000_000,
6016 outbound_capacity_msat: 10_000_000,
6017 next_outbound_htlc_limit_msat: 10_000_000,
6018 inbound_capacity_msat: 0,
6019 unspendable_punishment_reserve: None,
6020 confirmations_required: None,
6021 force_close_spend_delay: None,
6023 is_channel_ready: true,
6026 inbound_htlc_minimum_msat: None,
6027 inbound_htlc_maximum_msat: None,
6033 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
6034 let logger = DummyLogger {};
6035 let network_graph = read_network_graph(&logger);
6036 let scorer = FixedPenaltyScorer::with_penalty(0);
6037 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
6041 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
6042 let logger = DummyLogger {};
6043 let network_graph = read_network_graph(&logger);
6044 let scorer = FixedPenaltyScorer::with_penalty(0);
6045 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
6049 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
6050 let logger = DummyLogger {};
6051 let network_graph = read_network_graph(&logger);
6052 let params = ProbabilisticScoringParameters::default();
6053 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
6054 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
6058 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
6059 let logger = DummyLogger {};
6060 let network_graph = read_network_graph(&logger);
6061 let params = ProbabilisticScoringParameters::default();
6062 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
6063 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
6066 fn generate_routes<S: Score>(
6067 bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
6068 features: InvoiceFeatures
6070 let nodes = graph.read_only().nodes().clone();
6071 let payer = payer_pubkey();
6072 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6073 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6075 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
6076 let mut routes = Vec::new();
6077 let mut route_endpoints = Vec::new();
6078 let mut seed: usize = 0xdeadbeef;
6079 'load_endpoints: for _ in 0..150 {
6082 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
6084 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
6085 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
6086 let first_hop = first_hop(src);
6087 let amt = seed as u64 % 1_000_000;
6088 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
6090 route_endpoints.push((first_hop, params, amt));
6091 continue 'load_endpoints;
6096 // ...and seed the scorer with success and failure data...
6097 for route in routes {
6098 let amount = route.get_total_amount();
6099 if amount < 250_000 {
6100 for path in route.paths {
6101 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
6103 } else if amount > 750_000 {
6104 for path in route.paths {
6105 let short_channel_id = path[path.len() / 2].short_channel_id;
6106 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
6111 // Because we've changed channel scores, its possible we'll take different routes to the
6112 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
6113 // requires a too-high CLTV delta.
6114 route_endpoints.retain(|(first_hop, params, amt)| {
6115 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
6117 route_endpoints.truncate(100);
6118 assert_eq!(route_endpoints.len(), 100);
6120 // ...then benchmark finding paths between the nodes we learned.
6123 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
6124 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());