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, 2)),
257 (6, expiry_time, option),
258 (7, previously_failed_channels, vec_type),
261 impl PaymentParameters {
262 /// Creates a payee with the node id of the given `pubkey`.
263 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
269 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
270 max_path_count: DEFAULT_MAX_PATH_COUNT,
271 max_channel_saturation_power_of_half: 2,
272 previously_failed_channels: Vec::new(),
276 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
277 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
278 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
281 /// Includes the payee's features.
283 /// (C-not exported) since bindings don't support move semantics
284 pub fn with_features(self, features: InvoiceFeatures) -> Self {
285 Self { features: Some(features), ..self }
288 /// Includes hints for routing to the payee.
290 /// (C-not exported) since bindings don't support move semantics
291 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
292 Self { route_hints, ..self }
295 /// Includes a payment expiration in seconds relative to the UNIX epoch.
297 /// (C-not exported) since bindings don't support move semantics
298 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
299 Self { expiry_time: Some(expiry_time), ..self }
302 /// Includes a limit for the total CLTV expiry delta which is considered during routing
304 /// (C-not exported) since bindings don't support move semantics
305 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
306 Self { max_total_cltv_expiry_delta, ..self }
309 /// Includes a limit for the maximum number of payment paths that may be used.
311 /// (C-not exported) since bindings don't support move semantics
312 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
313 Self { max_path_count, ..self }
316 /// Includes a limit for the maximum number of payment paths that may be used.
318 /// (C-not exported) since bindings don't support move semantics
319 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
320 Self { max_channel_saturation_power_of_half, ..self }
324 /// A list of hops along a payment path terminating with a channel to the recipient.
325 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
326 pub struct RouteHint(pub Vec<RouteHintHop>);
328 impl Writeable for RouteHint {
329 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
330 (self.0.len() as u64).write(writer)?;
331 for hop in self.0.iter() {
338 impl Readable for RouteHint {
339 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
340 let hop_count: u64 = Readable::read(reader)?;
341 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
342 for _ in 0..hop_count {
343 hops.push(Readable::read(reader)?);
349 /// A channel descriptor for a hop along a payment path.
350 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
351 pub struct RouteHintHop {
352 /// The node_id of the non-target end of the route
353 pub src_node_id: PublicKey,
354 /// The short_channel_id of this channel
355 pub short_channel_id: u64,
356 /// The fees which must be paid to use this channel
357 pub fees: RoutingFees,
358 /// The difference in CLTV values between this node and the next node.
359 pub cltv_expiry_delta: u16,
360 /// The minimum value, in msat, which must be relayed to the next hop.
361 pub htlc_minimum_msat: Option<u64>,
362 /// The maximum value in msat available for routing with a single HTLC.
363 pub htlc_maximum_msat: Option<u64>,
366 impl_writeable_tlv_based!(RouteHintHop, {
367 (0, src_node_id, required),
368 (1, htlc_minimum_msat, option),
369 (2, short_channel_id, required),
370 (3, htlc_maximum_msat, option),
372 (6, cltv_expiry_delta, required),
375 #[derive(Eq, PartialEq)]
376 struct RouteGraphNode {
378 lowest_fee_to_peer_through_node: u64,
379 lowest_fee_to_node: u64,
380 total_cltv_delta: u32,
381 // The maximum value a yet-to-be-constructed payment path might flow through this node.
382 // This value is upper-bounded by us by:
383 // - how much is needed for a path being constructed
384 // - how much value can channels following this node (up to the destination) can contribute,
385 // considering their capacity and fees
386 value_contribution_msat: u64,
387 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
388 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
389 path_htlc_minimum_msat: u64,
390 /// All penalties incurred from this hop on the way to the destination, as calculated using
392 path_penalty_msat: u64,
393 /// The number of hops walked up to this node.
394 path_length_to_node: u8,
397 impl cmp::Ord for RouteGraphNode {
398 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
399 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
400 .saturating_add(other.path_penalty_msat);
401 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
402 .saturating_add(self.path_penalty_msat);
403 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
407 impl cmp::PartialOrd for RouteGraphNode {
408 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
409 Some(self.cmp(other))
413 /// A wrapper around the various hop representations.
415 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
416 #[derive(Clone, Debug)]
417 enum CandidateRouteHop<'a> {
418 /// A hop from the payer, where the outbound liquidity is known.
420 details: &'a ChannelDetails,
422 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
424 info: DirectedChannelInfoWithUpdate<'a>,
425 short_channel_id: u64,
427 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
429 hint: &'a RouteHintHop,
433 impl<'a> CandidateRouteHop<'a> {
434 fn short_channel_id(&self) -> u64 {
436 CandidateRouteHop::FirstHop { details } => details.get_outbound_payment_scid().unwrap(),
437 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
438 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
442 // NOTE: This may alloc memory so avoid calling it in a hot code path.
443 fn features(&self) -> ChannelFeatures {
445 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
446 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
447 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
451 fn cltv_expiry_delta(&self) -> u32 {
453 CandidateRouteHop::FirstHop { .. } => 0,
454 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
455 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
459 fn htlc_minimum_msat(&self) -> u64 {
461 CandidateRouteHop::FirstHop { .. } => 0,
462 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
463 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
467 fn fees(&self) -> RoutingFees {
469 CandidateRouteHop::FirstHop { .. } => RoutingFees {
470 base_msat: 0, proportional_millionths: 0,
472 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
473 CandidateRouteHop::PrivateHop { hint } => hint.fees,
477 fn effective_capacity(&self) -> EffectiveCapacity {
479 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
480 liquidity_msat: details.next_outbound_htlc_limit_msat,
482 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
483 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
489 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
490 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
492 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
493 EffectiveCapacity::Infinite => u64::max_value(),
494 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
495 EffectiveCapacity::MaximumHTLC { amount_msat } =>
496 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
497 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: None } =>
498 capacity_msat.checked_shr(saturation_shift).unwrap_or(0),
499 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat: Some(htlc_max) } =>
500 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_max),
504 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
505 -> bool where I1::Item: PartialEq<I2::Item> {
507 let a = iter_a.next();
508 let b = iter_b.next();
509 if a.is_none() && b.is_none() { return true; }
510 if a.is_none() || b.is_none() { return false; }
511 if a.unwrap().ne(&b.unwrap()) { return false; }
515 /// It's useful to keep track of the hops associated with the fees required to use them,
516 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
517 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
518 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
520 struct PathBuildingHop<'a> {
521 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
522 // is a larger refactor and will require careful performance analysis.
524 candidate: CandidateRouteHop<'a>,
527 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
528 src_lowest_inbound_fees: RoutingFees,
529 /// All the fees paid *after* this channel on the way to the destination
530 next_hops_fee_msat: u64,
531 /// Fee paid for the use of the current channel (see candidate.fees()).
532 /// The value will be actually deducted from the counterparty balance on the previous link.
533 hop_use_fee_msat: u64,
534 /// Used to compare channels when choosing the for routing.
535 /// Includes paying for the use of a hop and the following hops, as well as
536 /// an estimated cost of reaching this hop.
537 /// Might get stale when fees are recomputed. Primarily for internal use.
539 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
540 /// walk and may be invalid thereafter.
541 path_htlc_minimum_msat: u64,
542 /// All penalties incurred from this channel on the way to the destination, as calculated using
544 path_penalty_msat: u64,
545 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
546 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
547 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
548 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
549 /// avoid processing them again.
551 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
552 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
553 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
554 // value_contribution_msat, which requires tracking it here. See comments below where it is
555 // used for more info.
556 value_contribution_msat: u64,
559 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
560 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
561 let mut debug_struct = f.debug_struct("PathBuildingHop");
563 .field("node_id", &self.node_id)
564 .field("short_channel_id", &self.candidate.short_channel_id())
565 .field("total_fee_msat", &self.total_fee_msat)
566 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
567 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
568 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat - (&self.next_hops_fee_msat + &self.hop_use_fee_msat)))
569 .field("path_penalty_msat", &self.path_penalty_msat)
570 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
571 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
572 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
573 let debug_struct = debug_struct
574 .field("value_contribution_msat", &self.value_contribution_msat);
575 debug_struct.finish()
579 // Instantiated with a list of hops with correct data in them collected during path finding,
580 // an instance of this struct should be further modified only via given methods.
582 struct PaymentPath<'a> {
583 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
586 impl<'a> PaymentPath<'a> {
587 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
588 fn get_value_msat(&self) -> u64 {
589 self.hops.last().unwrap().0.fee_msat
592 fn get_path_penalty_msat(&self) -> u64 {
593 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
596 fn get_total_fee_paid_msat(&self) -> u64 {
597 if self.hops.len() < 1 {
601 // Can't use next_hops_fee_msat because it gets outdated.
602 for (i, (hop, _)) in self.hops.iter().enumerate() {
603 if i != self.hops.len() - 1 {
604 result += hop.fee_msat;
610 fn get_cost_msat(&self) -> u64 {
611 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
614 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
615 // to change fees may result in an inconsistency.
617 // Sometimes we call this function right after constructing a path which is inconsistent in
618 // that it the value being transferred has decreased while we were doing path finding, leading
619 // to the fees being paid not lining up with the actual limits.
621 // Note that this function is not aware of the available_liquidity limit, and thus does not
622 // support increasing the value being transferred beyond what was selected during the initial
624 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
625 let mut total_fee_paid_msat = 0 as u64;
626 for i in (0..self.hops.len()).rev() {
627 let last_hop = i == self.hops.len() - 1;
629 // For non-last-hop, this value will represent the fees paid on the current hop. It
630 // will consist of the fees for the use of the next hop, and extra fees to match
631 // htlc_minimum_msat of the current channel. Last hop is handled separately.
632 let mut cur_hop_fees_msat = 0;
634 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
637 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
638 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
639 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
640 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
641 // set it too high just to maliciously take more fees by exploiting this
642 // match htlc_minimum_msat logic.
643 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
644 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
645 // Note that there is a risk that *previous hops* (those closer to us, as we go
646 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
648 // This might make us end up with a broken route, although this should be super-rare
649 // in practice, both because of how healthy channels look like, and how we pick
650 // channels in add_entry.
651 // Also, this can't be exploited more heavily than *announce a free path and fail
653 cur_hop_transferred_amount_msat += extra_fees_msat;
654 total_fee_paid_msat += extra_fees_msat;
655 cur_hop_fees_msat += extra_fees_msat;
659 // Final hop is a special case: it usually has just value_msat (by design), but also
660 // it still could overpay for the htlc_minimum_msat.
661 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
663 // Propagate updated fees for the use of the channels to one hop back, where they
664 // will be actually paid (fee_msat). The last hop is handled above separately.
665 cur_hop.fee_msat = cur_hop_fees_msat;
668 // Fee for the use of the current hop which will be deducted on the previous hop.
669 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
670 // this channel is free for us.
672 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
673 cur_hop.hop_use_fee_msat = new_fee;
674 total_fee_paid_msat += new_fee;
676 // It should not be possible because this function is called only to reduce the
677 // value. In that case, compute_fee was already called with the same fees for
678 // larger amount and there was no overflow.
686 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
687 let proportional_fee_millions =
688 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
689 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
690 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
694 // This function may be (indirectly) called without any verification,
695 // with channel_fees provided by a caller. We should handle it gracefully.
700 /// The default `features` we assume for a node in a route, when no `features` are known about that
703 /// Default features are:
704 /// * variable_length_onion_optional
705 fn default_node_features() -> NodeFeatures {
706 let mut features = NodeFeatures::empty();
707 features.set_variable_length_onion_optional();
711 /// Finds a route from us (payer) to the given target node (payee).
713 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
714 /// Without this, MPP will only be used if the payee's features are available in the network graph.
716 /// Private routing paths between a public node and the target may be included in `params.payee`.
718 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
719 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
720 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
722 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
723 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
724 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
728 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
729 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
734 /// Panics if first_hops contains channels without short_channel_ids;
735 /// [`ChannelManager::list_usable_channels`] will never include such channels.
737 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
738 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
739 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
740 pub fn find_route<L: Deref, GL: Deref, S: Score>(
741 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
742 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
743 scorer: &S, random_seed_bytes: &[u8; 32]
744 ) -> Result<Route, LightningError>
745 where L::Target: Logger, GL::Target: Logger {
746 let graph_lock = network_graph.read_only();
747 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
748 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, scorer,
750 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
754 pub(crate) fn get_route<L: Deref, S: Score>(
755 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
756 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
757 logger: L, scorer: &S, _random_seed_bytes: &[u8; 32]
758 ) -> Result<Route, LightningError>
759 where L::Target: Logger {
760 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
761 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
763 if payee_node_id == our_node_id {
764 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
767 if final_value_msat > MAX_VALUE_MSAT {
768 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
771 if final_value_msat == 0 {
772 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
775 for route in payment_params.route_hints.iter() {
776 for hop in &route.0 {
777 if hop.src_node_id == payment_params.payee_pubkey {
778 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
782 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
783 return Err(LightningError{err: "Can't find a route where the maximum total CLTV expiry delta is below the final CLTV expiry.".to_owned(), action: ErrorAction::IgnoreError});
786 // The general routing idea is the following:
787 // 1. Fill first/last hops communicated by the caller.
788 // 2. Attempt to construct a path from payer to payee for transferring
789 // any ~sufficient (described later) value.
790 // If succeed, remember which channels were used and how much liquidity they have available,
791 // so that future paths don't rely on the same liquidity.
792 // 3. Proceed to the next step if:
793 // - we hit the recommended target value;
794 // - OR if we could not construct a new path. Any next attempt will fail too.
795 // Otherwise, repeat step 2.
796 // 4. See if we managed to collect paths which aggregately are able to transfer target value
797 // (not recommended value).
798 // 5. If yes, proceed. If not, fail routing.
799 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
800 // transferred up to the transfer target value.
801 // 7. Reduce the value of the last path until we are sending only the target value.
802 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
803 // them so that we're not sending two HTLCs along the same path.
805 // As for the actual search algorithm,
806 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
807 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
809 // We are not a faithful Dijkstra's implementation because we can change values which impact
810 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
811 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
812 // the value we are currently attempting to send over a path, we simply reduce the value being
813 // sent along the path for any hops after that channel. This may imply that later fees (which
814 // we've already tabulated) are lower because a smaller value is passing through the channels
815 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
816 // channels which were selected earlier (and which may still be used for other paths without a
817 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
820 // One potentially problematic case for this algorithm would be if there are many
821 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
822 // graph walking), we may never find a path which is not liquidity-limited and has lower
823 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
824 // Because we only consider paths with at least 5% of the total value being sent, the damage
825 // from such a case should be limited, however this could be further reduced in the future by
826 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
827 // limits for the purposes of fee calculation.
829 // Alternatively, we could store more detailed path information in the heap (targets, below)
830 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
831 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
832 // and practically (as we would need to store dynamically-allocated path information in heap
833 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
834 // results of such an algorithm would likely be biased towards lower-value paths.
836 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
837 // outside of our current search value, running a path search more times to gather candidate
838 // paths at different values. While this may be acceptable, further path searches may increase
839 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
840 // graph for candidate paths, calculating the maximum value which can realistically be sent at
841 // the same time, remaining generic across different payment values.
843 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
844 // to use as the A* heuristic beyond just the cost to get one node further than the current
847 let network_channels = network_graph.channels();
848 let network_nodes = network_graph.nodes();
850 if payment_params.max_path_count == 0 {
851 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
854 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
855 // it. If the payee supports it they're supposed to include it in the invoice, so that should
857 let allow_mpp = if payment_params.max_path_count == 1 {
859 } else if let Some(features) = &payment_params.features {
860 features.supports_basic_mpp()
861 } else if let Some(node) = network_nodes.get(&payee_node_id) {
862 if let Some(node_info) = node.announcement_info.as_ref() {
863 node_info.features.supports_basic_mpp()
867 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
868 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
869 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
872 // Prepare the data we'll use for payee-to-payer search by
873 // inserting first hops suggested by the caller as targets.
874 // Our search will then attempt to reach them while traversing from the payee node.
875 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
876 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
877 if let Some(hops) = first_hops {
879 if chan.get_outbound_payment_scid().is_none() {
880 panic!("first_hops should be filled in with usable channels, not pending ones");
882 if chan.counterparty.node_id == *our_node_pubkey {
883 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
886 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
887 .or_insert(Vec::new())
890 if first_hop_targets.is_empty() {
891 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
895 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
896 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
897 // adding duplicate entries when we find a better path to a given node.
898 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
900 // Map from node_id to information about the best current path to that node, including feerate
902 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
904 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
905 // indicating that we may wish to try again with a higher value, potentially paying to meet an
906 // htlc_minimum with extra fees while still finding a cheaper path.
907 let mut hit_minimum_limit;
909 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
910 // We start with a path_value of the exact amount we want, and if that generates a route we may
911 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
912 // amount we want in total across paths, selecting the best subset at the end.
913 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
914 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
915 let mut path_value_msat = final_value_msat;
917 // Routing Fragmentation Mitigation heuristic:
919 // Routing fragmentation across many payment paths increases the overall routing
920 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
921 // Taking too many smaller paths also increases the chance of payment failure.
922 // Thus to avoid this effect, we require from our collected links to provide
923 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
924 // This requirement is currently set to be 1/max_path_count of the payment
925 // value to ensure we only ever return routes that do not violate this limit.
926 let minimal_value_contribution_msat: u64 = if allow_mpp {
927 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
932 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
933 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
934 // drop the requirement by setting this to 0.
935 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
937 // Keep track of how much liquidity has been used in selected channels. Used to determine
938 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
939 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
940 // liquidity used in one direction will not offset any used in the opposite direction.
941 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
942 HashMap::with_capacity(network_nodes.len());
944 // Keeping track of how much value we already collected across other paths. Helps to decide
945 // when we want to stop looking for new paths.
946 let mut already_collected_value_msat = 0;
948 for (_, channels) in first_hop_targets.iter_mut() {
949 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
952 // First, if channels are below `recommended_value_msat`, sort them in descending order,
953 // preferring larger channels to avoid splitting the payment into more MPP parts than is
956 // Second, because simply always sorting in descending order would always use our largest
957 // available outbound capacity, needlessly fragmenting our available channel capacities,
958 // sort channels above `recommended_value_msat` in ascending order, preferring channels
959 // which have enough, but not too much, capacity for the payment.
960 channels.sort_unstable_by(|chan_a, chan_b| {
961 if chan_b.next_outbound_htlc_limit_msat < recommended_value_msat || chan_a.next_outbound_htlc_limit_msat < recommended_value_msat {
962 // Sort in descending order
963 chan_b.next_outbound_htlc_limit_msat.cmp(&chan_a.next_outbound_htlc_limit_msat)
965 // Sort in ascending order
966 chan_a.next_outbound_htlc_limit_msat.cmp(&chan_b.next_outbound_htlc_limit_msat)
971 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
973 macro_rules! add_entry {
974 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
975 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
976 // since that value has to be transferred over this channel.
977 // Returns whether this channel caused an update to `targets`.
978 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
979 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
980 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
981 // We "return" whether we updated the path at the end, via this:
982 let mut did_add_update_path_to_src_node = false;
983 // Channels to self should not be used. This is more of belt-and-suspenders, because in
984 // practice these cases should be caught earlier:
985 // - for regular channels at channel announcement (TODO)
986 // - for first and last hops early in get_route
987 if $src_node_id != $dest_node_id {
988 let short_channel_id = $candidate.short_channel_id();
989 let effective_capacity = $candidate.effective_capacity();
990 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
992 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
993 // It may be misleading because we might later choose to reduce the value transferred
994 // over these channels, and the channel which was insufficient might become sufficient.
995 // Worst case: we drop a good channel here because it can't cover the high following
996 // fees caused by one expensive channel, but then this channel could have been used
997 // if the amount being transferred over this path is lower.
998 // We do this for now, but this is a subject for removal.
999 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1000 let used_liquidity_msat = used_channel_liquidities
1001 .get(&(short_channel_id, $src_node_id < $dest_node_id))
1002 .map_or(0, |used_liquidity_msat| {
1003 available_value_contribution_msat = available_value_contribution_msat
1004 .saturating_sub(*used_liquidity_msat);
1005 *used_liquidity_msat
1008 // Verify the liquidity offered by this channel complies to the minimal contribution.
1009 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1010 // Do not consider candidate hops that would exceed the maximum path length.
1011 let path_length_to_node = $next_hops_path_length + 1;
1012 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1014 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1015 // In order to already account for some of the privacy enhancing random CLTV
1016 // expiry delta offset we add on top later, we subtract a rough estimate
1017 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1018 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1019 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1020 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1021 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1022 .saturating_add($candidate.cltv_expiry_delta());
1023 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1025 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1026 // Includes paying fees for the use of the following channels.
1027 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1028 Some(result) => result,
1029 // Can't overflow due to how the values were computed right above.
1030 None => unreachable!(),
1032 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1033 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1034 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1036 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1037 let may_overpay_to_meet_path_minimum_msat =
1038 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1039 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1040 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1041 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1043 let payment_failed_on_this_channel =
1044 payment_params.previously_failed_channels.contains(&short_channel_id);
1046 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1047 // bother considering this channel. If retrying with recommended_value_msat may
1048 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1049 // around again with a higher amount.
1050 if !contributes_sufficient_value || exceeds_max_path_length ||
1051 exceeds_cltv_delta_limit || payment_failed_on_this_channel {
1052 // Path isn't useful, ignore it and move on.
1053 } else if may_overpay_to_meet_path_minimum_msat {
1054 hit_minimum_limit = true;
1055 } else if over_path_minimum_msat {
1056 // Note that low contribution here (limited by available_liquidity_msat)
1057 // might violate htlc_minimum_msat on the hops which are next along the
1058 // payment path (upstream to the payee). To avoid that, we recompute
1059 // path fees knowing the final path contribution after constructing it.
1060 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
1061 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
1062 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
1063 .unwrap_or_else(|| u64::max_value());
1064 let hm_entry = dist.entry($src_node_id);
1065 let old_entry = hm_entry.or_insert_with(|| {
1066 // If there was previously no known way to access the source node
1067 // (recall it goes payee-to-payer) of short_channel_id, first add a
1068 // semi-dummy record just to compute the fees to reach the source node.
1069 // This will affect our decision on selecting short_channel_id
1070 // as a way to reach the $dest_node_id.
1071 let mut fee_base_msat = 0;
1072 let mut fee_proportional_millionths = 0;
1073 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
1074 fee_base_msat = fees.base_msat;
1075 fee_proportional_millionths = fees.proportional_millionths;
1078 node_id: $dest_node_id.clone(),
1079 candidate: $candidate.clone(),
1081 src_lowest_inbound_fees: RoutingFees {
1082 base_msat: fee_base_msat,
1083 proportional_millionths: fee_proportional_millionths,
1085 next_hops_fee_msat: u64::max_value(),
1086 hop_use_fee_msat: u64::max_value(),
1087 total_fee_msat: u64::max_value(),
1088 path_htlc_minimum_msat,
1089 path_penalty_msat: u64::max_value(),
1090 was_processed: false,
1091 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1092 value_contribution_msat,
1096 #[allow(unused_mut)] // We only use the mut in cfg(test)
1097 let mut should_process = !old_entry.was_processed;
1098 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1100 // In test/fuzzing builds, we do extra checks to make sure the skipping
1101 // of already-seen nodes only happens in cases we expect (see below).
1102 if !should_process { should_process = true; }
1106 let mut hop_use_fee_msat = 0;
1107 let mut total_fee_msat = $next_hops_fee_msat;
1109 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1110 // will have the same effective-fee
1111 if $src_node_id != our_node_id {
1112 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1113 // max_value means we'll always fail
1114 // the old_entry.total_fee_msat > total_fee_msat check
1115 None => total_fee_msat = u64::max_value(),
1117 hop_use_fee_msat = fee_msat;
1118 total_fee_msat += hop_use_fee_msat;
1119 // When calculating the lowest inbound fees to a node, we
1120 // calculate fees here not based on the actual value we think
1121 // will flow over this channel, but on the minimum value that
1122 // we'll accept flowing over it. The minimum accepted value
1123 // is a constant through each path collection run, ensuring
1124 // consistent basis. Otherwise we may later find a
1125 // different path to the source node that is more expensive,
1126 // but which we consider to be cheaper because we are capacity
1127 // constrained and the relative fee becomes lower.
1128 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1129 .map(|a| a.checked_add(total_fee_msat)) {
1134 total_fee_msat = u64::max_value();
1141 let channel_usage = ChannelUsage {
1142 amount_msat: amount_to_transfer_over_msat,
1143 inflight_htlc_msat: used_liquidity_msat,
1146 let channel_penalty_msat = scorer.channel_penalty_msat(
1147 short_channel_id, &$src_node_id, &$dest_node_id, channel_usage
1149 let path_penalty_msat = $next_hops_path_penalty_msat
1150 .saturating_add(channel_penalty_msat);
1151 let new_graph_node = RouteGraphNode {
1152 node_id: $src_node_id,
1153 lowest_fee_to_peer_through_node: total_fee_msat,
1154 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1155 total_cltv_delta: hop_total_cltv_delta,
1156 value_contribution_msat: value_contribution_msat,
1157 path_htlc_minimum_msat,
1159 path_length_to_node,
1162 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1163 // if this way is cheaper than the already known
1164 // (considering the cost to "reach" this channel from the route destination,
1165 // the cost of using this channel,
1166 // and the cost of routing to the source node of this channel).
1167 // Also, consider that htlc_minimum_msat_difference, because we might end up
1168 // paying it. Consider the following exploit:
1169 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1170 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1171 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1172 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1174 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1175 // but it may require additional tracking - we don't want to double-count
1176 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1177 // can't use something that may decrease on future hops.
1178 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1179 .saturating_add(old_entry.path_penalty_msat);
1180 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1181 .saturating_add(path_penalty_msat);
1183 if !old_entry.was_processed && new_cost < old_cost {
1184 targets.push(new_graph_node);
1185 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1186 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1187 old_entry.total_fee_msat = total_fee_msat;
1188 old_entry.node_id = $dest_node_id.clone();
1189 old_entry.candidate = $candidate.clone();
1190 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1191 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1192 old_entry.path_penalty_msat = path_penalty_msat;
1193 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1195 old_entry.value_contribution_msat = value_contribution_msat;
1197 did_add_update_path_to_src_node = true;
1198 } else if old_entry.was_processed && new_cost < old_cost {
1199 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1201 // If we're skipping processing a node which was previously
1202 // processed even though we found another path to it with a
1203 // cheaper fee, check that it was because the second path we
1204 // found (which we are processing now) has a lower value
1205 // contribution due to an HTLC minimum limit.
1207 // e.g. take a graph with two paths from node 1 to node 2, one
1208 // through channel A, and one through channel B. Channel A and
1209 // B are both in the to-process heap, with their scores set by
1210 // a higher htlc_minimum than fee.
1211 // Channel A is processed first, and the channels onwards from
1212 // node 1 are added to the to-process heap. Thereafter, we pop
1213 // Channel B off of the heap, note that it has a much more
1214 // restrictive htlc_maximum_msat, and recalculate the fees for
1215 // all of node 1's channels using the new, reduced, amount.
1217 // This would be bogus - we'd be selecting a higher-fee path
1218 // with a lower htlc_maximum_msat instead of the one we'd
1219 // already decided to use.
1220 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1222 value_contribution_msat + path_penalty_msat <
1223 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1231 did_add_update_path_to_src_node
1235 let default_node_features = default_node_features();
1237 // Find ways (channels with destination) to reach a given node and store them
1238 // in the corresponding data structures (routing graph etc).
1239 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1240 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1241 // This data can later be helpful to optimize routing (pay lower fees).
1242 macro_rules! add_entries_to_cheapest_to_target_node {
1243 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1244 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1245 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1246 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1247 let was_processed = elem.was_processed;
1248 elem.was_processed = true;
1251 // Entries are added to dist in add_entry!() when there is a channel from a node.
1252 // Because there are no channels from payee, it will not have a dist entry at this point.
1253 // If we're processing any other node, it is always be the result of a channel from it.
1254 assert_eq!($node_id, payee_node_id);
1259 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1260 for details in first_channels {
1261 let candidate = CandidateRouteHop::FirstHop { details };
1262 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1263 $next_hops_value_contribution,
1264 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1265 $next_hops_cltv_delta, $next_hops_path_length);
1269 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1272 &default_node_features
1275 if !features.requires_unknown_bits() {
1276 for chan_id in $node.channels.iter() {
1277 let chan = network_channels.get(chan_id).unwrap();
1278 if !chan.features.requires_unknown_bits() {
1279 let (directed_channel, source) =
1280 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1281 if first_hops.is_none() || *source != our_node_id {
1282 if let Some(direction) = directed_channel.direction() {
1283 if direction.enabled {
1284 let candidate = CandidateRouteHop::PublicHop {
1285 info: directed_channel.with_update().unwrap(),
1286 short_channel_id: *chan_id,
1288 add_entry!(candidate, *source, $node_id,
1289 $fee_to_target_msat,
1290 $next_hops_value_contribution,
1291 $next_hops_path_htlc_minimum_msat,
1292 $next_hops_path_penalty_msat,
1293 $next_hops_cltv_delta, $next_hops_path_length);
1304 let mut payment_paths = Vec::<PaymentPath>::new();
1306 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1307 'paths_collection: loop {
1308 // For every new path, start from scratch, except for used_channel_liquidities, which
1309 // helps to avoid reusing previously selected paths in future iterations.
1312 hit_minimum_limit = false;
1314 // If first hop is a private channel and the only way to reach the payee, this is the only
1315 // place where it could be added.
1316 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1317 for details in first_channels {
1318 let candidate = CandidateRouteHop::FirstHop { details };
1319 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat,
1321 log_trace!(logger, "{} direct route to payee via SCID {}",
1322 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1326 // Add the payee as a target, so that the payee-to-payer
1327 // search algorithm knows what to start with.
1328 match network_nodes.get(&payee_node_id) {
1329 // The payee is not in our network graph, so nothing to add here.
1330 // There is still a chance of reaching them via last_hops though,
1331 // so don't yet fail the payment here.
1332 // If not, targets.pop() will not even let us enter the loop in step 2.
1335 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0, 0);
1340 // If a caller provided us with last hops, add them to routing targets. Since this happens
1341 // earlier than general path finding, they will be somewhat prioritized, although currently
1342 // it matters only if the fees are exactly the same.
1343 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1344 let first_hop_in_route = &(route.0)[0];
1345 let have_hop_src_in_graph =
1346 // Only add the hops in this route to our candidate set if either
1347 // we have a direct channel to the first hop or the first hop is
1348 // in the regular network graph.
1349 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1350 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1351 if have_hop_src_in_graph {
1352 // We start building the path from reverse, i.e., from payee
1353 // to the first RouteHintHop in the path.
1354 let hop_iter = route.0.iter().rev();
1355 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1356 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1357 let mut hop_used = true;
1358 let mut aggregate_next_hops_fee_msat: u64 = 0;
1359 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1360 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1361 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1362 let mut aggregate_next_hops_path_length: u8 = 0;
1364 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1365 let source = NodeId::from_pubkey(&hop.src_node_id);
1366 let target = NodeId::from_pubkey(&prev_hop_id);
1367 let candidate = network_channels
1368 .get(&hop.short_channel_id)
1369 .and_then(|channel| channel.as_directed_to(&target))
1370 .and_then(|(channel, _)| channel.with_update())
1371 .map(|info| CandidateRouteHop::PublicHop {
1373 short_channel_id: hop.short_channel_id,
1375 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1377 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat,
1378 path_value_msat, aggregate_next_hops_path_htlc_minimum_msat,
1379 aggregate_next_hops_path_penalty_msat,
1380 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length) {
1381 // If this hop was not used then there is no use checking the preceding
1382 // hops in the RouteHint. We can break by just searching for a direct
1383 // channel between last checked hop and first_hop_targets.
1387 let used_liquidity_msat = used_channel_liquidities
1388 .get(&(hop.short_channel_id, source < target)).copied().unwrap_or(0);
1389 let channel_usage = ChannelUsage {
1390 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
1391 inflight_htlc_msat: used_liquidity_msat,
1392 effective_capacity: candidate.effective_capacity(),
1394 let channel_penalty_msat = scorer.channel_penalty_msat(
1395 hop.short_channel_id, &source, &target, channel_usage
1397 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1398 .saturating_add(channel_penalty_msat);
1400 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1401 .saturating_add(hop.cltv_expiry_delta as u32);
1403 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1406 // Searching for a direct channel between last checked hop and first_hop_targets
1407 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1408 for details in first_channels {
1409 let candidate = CandidateRouteHop::FirstHop { details };
1410 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1411 aggregate_next_hops_fee_msat, path_value_msat,
1412 aggregate_next_hops_path_htlc_minimum_msat,
1413 aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta,
1414 aggregate_next_hops_path_length);
1422 // In the next values of the iterator, the aggregate fees already reflects
1423 // the sum of value sent from payer (final_value_msat) and routing fees
1424 // for the last node in the RouteHint. We need to just add the fees to
1425 // route through the current node so that the preceding node (next iteration)
1427 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1428 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1429 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1431 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1432 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1433 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1434 .checked_add(hop_htlc_minimum_msat_inc);
1435 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1437 if idx == route.0.len() - 1 {
1438 // The last hop in this iterator is the first hop in
1439 // overall RouteHint.
1440 // If this hop connects to a node with which we have a direct channel,
1441 // ignore the network graph and, if the last hop was added, add our
1442 // direct channel to the candidate set.
1444 // Note that we *must* check if the last hop was added as `add_entry`
1445 // always assumes that the third argument is a node to which we have a
1447 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1448 for details in first_channels {
1449 let candidate = CandidateRouteHop::FirstHop { details };
1450 add_entry!(candidate, our_node_id,
1451 NodeId::from_pubkey(&hop.src_node_id),
1452 aggregate_next_hops_fee_msat, path_value_msat,
1453 aggregate_next_hops_path_htlc_minimum_msat,
1454 aggregate_next_hops_path_penalty_msat,
1455 aggregate_next_hops_cltv_delta,
1456 aggregate_next_hops_path_length);
1464 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1466 // At this point, targets are filled with the data from first and
1467 // last hops communicated by the caller, and the payment receiver.
1468 let mut found_new_path = false;
1471 // If this loop terminates due the exhaustion of targets, two situations are possible:
1472 // - not enough outgoing liquidity:
1473 // 0 < already_collected_value_msat < final_value_msat
1474 // - enough outgoing liquidity:
1475 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1476 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1477 // paths_collection will be stopped because found_new_path==false.
1478 // This is not necessarily a routing failure.
1479 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, mut value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, path_length_to_node, .. }) = targets.pop() {
1481 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1482 // traversing the graph and arrange the path out of what we found.
1483 if node_id == our_node_id {
1484 let mut new_entry = dist.remove(&our_node_id).unwrap();
1485 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1488 let mut features_set = false;
1489 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1490 for details in first_channels {
1491 if details.get_outbound_payment_scid().unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1492 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1493 features_set = true;
1499 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1500 if let Some(node_info) = node.announcement_info.as_ref() {
1501 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1503 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1506 // We can fill in features for everything except hops which were
1507 // provided via the invoice we're paying. We could guess based on the
1508 // recipient's features but for now we simply avoid guessing at all.
1512 // Means we succesfully traversed from the payer to the payee, now
1513 // save this path for the payment route. Also, update the liquidity
1514 // remaining on the used hops, so that we take them into account
1515 // while looking for more paths.
1516 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1520 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1521 Some(payment_hop) => payment_hop,
1522 // We can't arrive at None because, if we ever add an entry to targets,
1523 // we also fill in the entry in dist (see add_entry!).
1524 None => unreachable!(),
1526 // We "propagate" the fees one hop backward (topologically) here,
1527 // so that fees paid for a HTLC forwarding on the current channel are
1528 // associated with the previous channel (where they will be subtracted).
1529 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1530 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1532 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1533 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1535 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1536 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1538 let mut payment_path = PaymentPath {hops: ordered_hops};
1540 // We could have possibly constructed a slightly inconsistent path: since we reduce
1541 // value being transferred along the way, we could have violated htlc_minimum_msat
1542 // on some channels we already passed (assuming dest->source direction). Here, we
1543 // recompute the fees again, so that if that's the case, we match the currently
1544 // underpaid htlc_minimum_msat with fees.
1545 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
1546 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
1547 payment_path.update_value_and_recompute_fees(value_contribution_msat);
1549 // Since a path allows to transfer as much value as
1550 // the smallest channel it has ("bottleneck"), we should recompute
1551 // the fees so sender HTLC don't overpay fees when traversing
1552 // larger channels than the bottleneck. This may happen because
1553 // when we were selecting those channels we were not aware how much value
1554 // this path will transfer, and the relative fee for them
1555 // might have been computed considering a larger value.
1556 // Remember that we used these channels so that we don't rely
1557 // on the same liquidity in future paths.
1558 let mut prevented_redundant_path_selection = false;
1559 let prev_hop_iter = core::iter::once(&our_node_id)
1560 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
1561 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
1562 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
1563 let used_liquidity_msat = used_channel_liquidities
1564 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
1565 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
1566 .or_insert(spent_on_hop_msat);
1567 let hop_capacity = hop.candidate.effective_capacity();
1568 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
1569 if *used_liquidity_msat == hop_max_msat {
1570 // If this path used all of this channel's available liquidity, we know
1571 // this path will not be selected again in the next loop iteration.
1572 prevented_redundant_path_selection = true;
1574 debug_assert!(*used_liquidity_msat <= hop_max_msat);
1576 if !prevented_redundant_path_selection {
1577 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1578 // we'll probably end up picking the same path again on the next iteration.
1579 // Decrease the available liquidity of a hop in the middle of the path.
1580 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1581 let exhausted = u64::max_value();
1582 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1583 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
1584 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
1587 // Track the total amount all our collected paths allow to send so that we know
1588 // when to stop looking for more paths
1589 already_collected_value_msat += value_contribution_msat;
1591 payment_paths.push(payment_path);
1592 found_new_path = true;
1593 break 'path_construction;
1596 // If we found a path back to the payee, we shouldn't try to process it again. This is
1597 // the equivalent of the `elem.was_processed` check in
1598 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1599 if node_id == payee_node_id { continue 'path_construction; }
1601 // Otherwise, since the current target node is not us,
1602 // keep "unrolling" the payment graph from payee to payer by
1603 // finding a way to reach the current target from the payer side.
1604 match network_nodes.get(&node_id) {
1607 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
1608 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
1609 total_cltv_delta, path_length_to_node);
1615 if !found_new_path && channel_saturation_pow_half != 0 {
1616 channel_saturation_pow_half = 0;
1617 continue 'paths_collection;
1619 // If we don't support MPP, no use trying to gather more value ever.
1620 break 'paths_collection;
1624 // Stop either when the recommended value is reached or if no new path was found in this
1626 // In the latter case, making another path finding attempt won't help,
1627 // because we deterministically terminated the search due to low liquidity.
1628 if !found_new_path && channel_saturation_pow_half != 0 {
1629 channel_saturation_pow_half = 0;
1630 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1631 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1632 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1633 break 'paths_collection;
1634 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1635 // Further, if this was our first walk of the graph, and we weren't limited by an
1636 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1637 // limited by an htlc_minimum_msat value, find another path with a higher value,
1638 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1639 // still keeping a lower total fee than this path.
1640 if !hit_minimum_limit {
1641 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1642 break 'paths_collection;
1644 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1645 path_value_msat = recommended_value_msat;
1650 if payment_paths.len() == 0 {
1651 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1654 if already_collected_value_msat < final_value_msat {
1655 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1659 let mut selected_route = payment_paths;
1661 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
1662 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
1664 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
1665 // the value they contribute towards the payment amount.
1666 // We sort in descending order as we will remove from the front in `retain`, next.
1667 selected_route.sort_unstable_by(|a, b|
1668 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
1669 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
1672 // We should make sure that at least 1 path left.
1673 let mut paths_left = selected_route.len();
1674 selected_route.retain(|path| {
1675 if paths_left == 1 {
1678 let path_value_msat = path.get_value_msat();
1679 if path_value_msat <= overpaid_value_msat {
1680 overpaid_value_msat -= path_value_msat;
1686 debug_assert!(selected_route.len() > 0);
1688 if overpaid_value_msat != 0 {
1690 // Now, subtract the remaining overpaid value from the most-expensive path.
1691 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1692 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1693 selected_route.sort_unstable_by(|a, b| {
1694 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1695 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1696 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1698 let expensive_payment_path = selected_route.first_mut().unwrap();
1700 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
1701 // can't go negative.
1702 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1703 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1707 // Sort by the path itself and combine redundant paths.
1708 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
1709 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
1711 selected_route.sort_unstable_by_key(|path| {
1712 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
1713 debug_assert!(path.hops.len() <= key.len());
1714 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
1719 for idx in 0..(selected_route.len() - 1) {
1720 if idx + 1 >= selected_route.len() { break; }
1721 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
1722 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
1723 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
1724 selected_route[idx].update_value_and_recompute_fees(new_value);
1725 selected_route.remove(idx + 1);
1729 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1730 for payment_path in selected_route {
1731 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1733 pubkey: PublicKey::from_slice(payment_hop.node_id.as_slice()).map_err(|_| LightningError{err: format!("Public key {:?} is invalid", &payment_hop.node_id), action: ErrorAction::IgnoreAndLog(Level::Trace)})?,
1734 node_features: node_features.clone(),
1735 short_channel_id: payment_hop.candidate.short_channel_id(),
1736 channel_features: payment_hop.candidate.features(),
1737 fee_msat: payment_hop.fee_msat,
1738 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1740 }).collect::<Vec<_>>();
1741 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1742 // applicable for the previous hop.
1743 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1744 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1746 selected_paths.push(path);
1748 // Make sure we would never create a route with more paths than we allow.
1749 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
1751 if let Some(features) = &payment_params.features {
1752 for path in selected_paths.iter_mut() {
1753 if let Ok(route_hop) = path.last_mut().unwrap() {
1754 route_hop.node_features = features.to_context();
1760 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1761 payment_params: Some(payment_params.clone()),
1763 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1767 // When an adversarial intermediary node observes a payment, it may be able to infer its
1768 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1769 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1770 // payment path by adding a randomized 'shadow route' offset to the final hop.
1771 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
1772 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
1774 let network_channels = network_graph.channels();
1775 let network_nodes = network_graph.nodes();
1777 for path in route.paths.iter_mut() {
1778 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1780 // Remember the last three nodes of the random walk and avoid looping back on them.
1781 // Init with the last three nodes from the actual path, if possible.
1782 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1783 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1784 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1786 // Choose the last publicly known node as the starting point for the random walk.
1787 let mut cur_hop: Option<NodeId> = None;
1788 let mut path_nonce = [0u8; 12];
1789 if let Some(starting_hop) = path.iter().rev()
1790 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1791 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1792 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1795 // Init PRNG with the path-dependant nonce, which is static for private paths.
1796 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1797 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1799 // Pick a random path length in [1 .. 3]
1800 prng.process_in_place(&mut random_path_bytes);
1801 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1803 for random_hop in 0..random_walk_length {
1804 // If we don't find a suitable offset in the public network graph, we default to
1805 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1806 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1808 if let Some(cur_node_id) = cur_hop {
1809 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1810 // Randomly choose the next unvisited hop.
1811 prng.process_in_place(&mut random_path_bytes);
1812 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1813 .checked_rem(cur_node.channels.len())
1814 .and_then(|index| cur_node.channels.get(index))
1815 .and_then(|id| network_channels.get(id)) {
1816 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1817 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1818 nodes_to_avoid[random_hop] = *next_id;
1819 dir_info.direction().map(|channel_update_info| {
1820 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1821 cur_hop = Some(*next_id);
1829 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1830 .checked_add(random_hop_offset)
1831 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1834 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1835 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1836 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1838 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1839 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1840 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1841 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1842 max_path_offset = cmp::max(
1843 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1844 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1845 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1847 // Add 'shadow' CLTV offset to the final hop
1848 if let Some(last_hop) = path.last_mut() {
1849 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1850 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1855 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
1856 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
1858 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
1859 pub fn build_route_from_hops<L: Deref, GL: Deref>(
1860 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
1861 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
1862 ) -> Result<Route, LightningError>
1863 where L::Target: Logger, GL::Target: Logger {
1864 let graph_lock = network_graph.read_only();
1865 let mut route = build_route_from_hops_internal(
1866 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
1867 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
1868 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
1872 fn build_route_from_hops_internal<L: Deref>(
1873 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
1874 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
1875 logger: L, random_seed_bytes: &[u8; 32]
1876 ) -> Result<Route, LightningError> where L::Target: Logger {
1879 our_node_id: NodeId,
1880 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
1883 impl Score for HopScorer {
1884 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
1885 _usage: ChannelUsage) -> u64
1887 let mut cur_id = self.our_node_id;
1888 for i in 0..self.hop_ids.len() {
1889 if let Some(next_id) = self.hop_ids[i] {
1890 if cur_id == *source && next_id == *target {
1901 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1903 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
1905 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
1907 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
1910 impl<'a> Writeable for HopScorer {
1912 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
1917 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
1918 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
1921 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
1922 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
1923 for i in 0..hops.len() {
1924 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
1927 let scorer = HopScorer { our_node_id, hop_ids };
1929 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
1930 final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)
1935 use routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
1936 use routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
1937 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
1938 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
1939 use routing::scoring::{ChannelUsage, Score, ProbabilisticScorer, ProbabilisticScoringParameters};
1940 use chain::transaction::OutPoint;
1941 use chain::keysinterface::KeysInterface;
1942 use ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
1943 use ln::msgs::{ErrorAction, LightningError, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1944 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate, MAX_VALUE_MSAT};
1945 use ln::channelmanager;
1946 use util::test_utils;
1947 use util::chacha20::ChaCha20;
1948 use util::ser::Writeable;
1950 use util::ser::Writer;
1952 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1953 use bitcoin::hashes::Hash;
1954 use bitcoin::network::constants::Network;
1955 use bitcoin::blockdata::constants::genesis_block;
1956 use bitcoin::blockdata::script::Builder;
1957 use bitcoin::blockdata::opcodes;
1958 use bitcoin::blockdata::transaction::TxOut;
1962 use bitcoin::secp256k1::{PublicKey,SecretKey};
1963 use bitcoin::secp256k1::{Secp256k1, All};
1966 use sync::{self, Arc};
1968 use core::convert::TryInto;
1970 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1971 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1972 channelmanager::ChannelDetails {
1973 channel_id: [0; 32],
1974 counterparty: channelmanager::ChannelCounterparty {
1977 unspendable_punishment_reserve: 0,
1978 forwarding_info: None,
1979 outbound_htlc_minimum_msat: None,
1980 outbound_htlc_maximum_msat: None,
1982 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1985 outbound_scid_alias: None,
1986 inbound_scid_alias: None,
1987 channel_value_satoshis: 0,
1990 outbound_capacity_msat,
1991 next_outbound_htlc_limit_msat: outbound_capacity_msat,
1992 inbound_capacity_msat: 42,
1993 unspendable_punishment_reserve: None,
1994 confirmations_required: None,
1995 force_close_spend_delay: None,
1996 is_outbound: true, is_channel_ready: true,
1997 is_usable: true, is_public: true,
1998 inbound_htlc_minimum_msat: None,
1999 inbound_htlc_maximum_msat: None,
2004 // Using the same keys for LN and BTC ids
2006 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2007 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
2009 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
2010 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
2012 let unsigned_announcement = UnsignedChannelAnnouncement {
2014 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2018 bitcoin_key_1: node_id_1,
2019 bitcoin_key_2: node_id_2,
2020 excess_data: Vec::new(),
2023 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
2024 let valid_announcement = ChannelAnnouncement {
2025 node_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
2026 node_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
2027 bitcoin_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
2028 bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
2029 contents: unsigned_announcement.clone(),
2031 match gossip_sync.handle_channel_announcement(&valid_announcement) {
2032 Ok(res) => assert!(res),
2038 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2039 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
2041 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
2042 let valid_channel_update = ChannelUpdate {
2043 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
2044 contents: update.clone()
2047 match gossip_sync.handle_channel_update(&valid_channel_update) {
2048 Ok(res) => assert!(res),
2053 fn add_or_update_node(
2054 gossip_sync: &P2PGossipSync<Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
2055 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
2057 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
2058 let unsigned_announcement = UnsignedNodeAnnouncement {
2064 addresses: Vec::new(),
2065 excess_address_data: Vec::new(),
2066 excess_data: Vec::new(),
2068 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
2069 let valid_announcement = NodeAnnouncement {
2070 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
2071 contents: unsigned_announcement.clone()
2074 match gossip_sync.handle_node_announcement(&valid_announcement) {
2080 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
2081 let privkeys: Vec<SecretKey> = (2..22).map(|i| {
2082 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
2085 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
2087 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
2088 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
2090 (our_privkey, our_id, privkeys, pubkeys)
2093 fn id_to_feature_flags(id: u8) -> Vec<u8> {
2094 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
2095 // test for it later.
2096 let idx = (id - 1) * 2 + 1;
2098 vec![1 << (idx - 8*3), 0, 0, 0]
2099 } else if idx > 8*2 {
2100 vec![1 << (idx - 8*2), 0, 0]
2101 } else if idx > 8*1 {
2102 vec![1 << (idx - 8*1), 0]
2108 fn build_line_graph() -> (
2109 Secp256k1<All>, sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
2110 P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
2111 sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>,
2113 let secp_ctx = Secp256k1::new();
2114 let logger = Arc::new(test_utils::TestLogger::new());
2115 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
2116 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
2117 let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
2118 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
2120 // Build network from our_id to node 19:
2121 // our_id -1(1)2- node0 -1(2)2- node1 - ... - node19
2122 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
2124 for (idx, (cur_privkey, next_privkey)) in core::iter::once(&our_privkey)
2125 .chain(privkeys.iter()).zip(privkeys.iter()).enumerate() {
2126 let cur_short_channel_id = (idx as u64) + 1;
2127 add_channel(&gossip_sync, &secp_ctx, &cur_privkey, &next_privkey,
2128 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), cur_short_channel_id);
2129 update_channel(&gossip_sync, &secp_ctx, &cur_privkey, UnsignedChannelUpdate {
2130 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2131 short_channel_id: cur_short_channel_id,
2132 timestamp: idx as u32,
2134 cltv_expiry_delta: 0,
2135 htlc_minimum_msat: 0,
2136 htlc_maximum_msat: MAX_VALUE_MSAT,
2138 fee_proportional_millionths: 0,
2139 excess_data: Vec::new()
2141 update_channel(&gossip_sync, &secp_ctx, &next_privkey, UnsignedChannelUpdate {
2142 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2143 short_channel_id: cur_short_channel_id,
2144 timestamp: (idx as u32)+1,
2146 cltv_expiry_delta: 0,
2147 htlc_minimum_msat: 0,
2148 htlc_maximum_msat: MAX_VALUE_MSAT,
2150 fee_proportional_millionths: 0,
2151 excess_data: Vec::new()
2153 add_or_update_node(&gossip_sync, &secp_ctx, next_privkey,
2154 NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
2157 (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
2160 fn build_graph() -> (
2162 sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>,
2163 P2PGossipSync<sync::Arc<NetworkGraph<Arc<test_utils::TestLogger>>>, sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>>,
2164 sync::Arc<test_utils::TestChainSource>,
2165 sync::Arc<test_utils::TestLogger>,
2167 let secp_ctx = Secp256k1::new();
2168 let logger = Arc::new(test_utils::TestLogger::new());
2169 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
2170 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
2171 let network_graph = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
2172 let gossip_sync = P2PGossipSync::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
2173 // Build network from our_id to node6:
2175 // -1(1)2- node0 -1(3)2-
2177 // our_id -1(12)2- node7 -1(13)2--- node2
2179 // -1(2)2- node1 -1(4)2-
2182 // chan1 1-to-2: disabled
2183 // chan1 2-to-1: enabled, 0 fee
2185 // chan2 1-to-2: enabled, ignored fee
2186 // chan2 2-to-1: enabled, 0 fee
2188 // chan3 1-to-2: enabled, 0 fee
2189 // chan3 2-to-1: enabled, 100 msat fee
2191 // chan4 1-to-2: enabled, 100% fee
2192 // chan4 2-to-1: enabled, 0 fee
2194 // chan12 1-to-2: enabled, ignored fee
2195 // chan12 2-to-1: enabled, 0 fee
2197 // chan13 1-to-2: enabled, 200% fee
2198 // chan13 2-to-1: enabled, 0 fee
2201 // -1(5)2- node3 -1(8)2--
2205 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
2207 // -1(7)2- node5 -1(10)2-
2209 // Channels 5, 8, 9 and 10 are private channels.
2211 // chan5 1-to-2: enabled, 100 msat fee
2212 // chan5 2-to-1: enabled, 0 fee
2214 // chan6 1-to-2: enabled, 0 fee
2215 // chan6 2-to-1: enabled, 0 fee
2217 // chan7 1-to-2: enabled, 100% fee
2218 // chan7 2-to-1: enabled, 0 fee
2220 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
2221 // chan8 2-to-1: enabled, 0 fee
2223 // chan9 1-to-2: enabled, 1001 msat fee
2224 // chan9 2-to-1: enabled, 0 fee
2226 // chan10 1-to-2: enabled, 0 fee
2227 // chan10 2-to-1: enabled, 0 fee
2229 // chan11 1-to-2: enabled, 0 fee
2230 // chan11 2-to-1: enabled, 0 fee
2232 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
2234 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
2235 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2236 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2237 short_channel_id: 1,
2240 cltv_expiry_delta: 0,
2241 htlc_minimum_msat: 0,
2242 htlc_maximum_msat: MAX_VALUE_MSAT,
2244 fee_proportional_millionths: 0,
2245 excess_data: Vec::new()
2248 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
2250 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
2251 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2252 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2253 short_channel_id: 2,
2256 cltv_expiry_delta: (5 << 4) | 3,
2257 htlc_minimum_msat: 0,
2258 htlc_maximum_msat: MAX_VALUE_MSAT,
2259 fee_base_msat: u32::max_value(),
2260 fee_proportional_millionths: u32::max_value(),
2261 excess_data: Vec::new()
2263 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2265 short_channel_id: 2,
2268 cltv_expiry_delta: 0,
2269 htlc_minimum_msat: 0,
2270 htlc_maximum_msat: MAX_VALUE_MSAT,
2272 fee_proportional_millionths: 0,
2273 excess_data: Vec::new()
2276 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
2278 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
2279 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2280 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2281 short_channel_id: 12,
2284 cltv_expiry_delta: (5 << 4) | 3,
2285 htlc_minimum_msat: 0,
2286 htlc_maximum_msat: MAX_VALUE_MSAT,
2287 fee_base_msat: u32::max_value(),
2288 fee_proportional_millionths: u32::max_value(),
2289 excess_data: Vec::new()
2291 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2292 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2293 short_channel_id: 12,
2296 cltv_expiry_delta: 0,
2297 htlc_minimum_msat: 0,
2298 htlc_maximum_msat: MAX_VALUE_MSAT,
2300 fee_proportional_millionths: 0,
2301 excess_data: Vec::new()
2304 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
2306 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
2307 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2308 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2309 short_channel_id: 3,
2312 cltv_expiry_delta: (3 << 4) | 1,
2313 htlc_minimum_msat: 0,
2314 htlc_maximum_msat: MAX_VALUE_MSAT,
2316 fee_proportional_millionths: 0,
2317 excess_data: Vec::new()
2319 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2320 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2321 short_channel_id: 3,
2324 cltv_expiry_delta: (3 << 4) | 2,
2325 htlc_minimum_msat: 0,
2326 htlc_maximum_msat: MAX_VALUE_MSAT,
2328 fee_proportional_millionths: 0,
2329 excess_data: Vec::new()
2332 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2333 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2334 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2335 short_channel_id: 4,
2338 cltv_expiry_delta: (4 << 4) | 1,
2339 htlc_minimum_msat: 0,
2340 htlc_maximum_msat: MAX_VALUE_MSAT,
2342 fee_proportional_millionths: 1000000,
2343 excess_data: Vec::new()
2345 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2346 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2347 short_channel_id: 4,
2350 cltv_expiry_delta: (4 << 4) | 2,
2351 htlc_minimum_msat: 0,
2352 htlc_maximum_msat: MAX_VALUE_MSAT,
2354 fee_proportional_millionths: 0,
2355 excess_data: Vec::new()
2358 add_channel(&gossip_sync, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2359 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2360 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2361 short_channel_id: 13,
2364 cltv_expiry_delta: (13 << 4) | 1,
2365 htlc_minimum_msat: 0,
2366 htlc_maximum_msat: MAX_VALUE_MSAT,
2368 fee_proportional_millionths: 2000000,
2369 excess_data: Vec::new()
2371 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2372 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2373 short_channel_id: 13,
2376 cltv_expiry_delta: (13 << 4) | 2,
2377 htlc_minimum_msat: 0,
2378 htlc_maximum_msat: MAX_VALUE_MSAT,
2380 fee_proportional_millionths: 0,
2381 excess_data: Vec::new()
2384 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2386 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2387 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2388 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2389 short_channel_id: 6,
2392 cltv_expiry_delta: (6 << 4) | 1,
2393 htlc_minimum_msat: 0,
2394 htlc_maximum_msat: MAX_VALUE_MSAT,
2396 fee_proportional_millionths: 0,
2397 excess_data: Vec::new()
2399 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2400 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2401 short_channel_id: 6,
2404 cltv_expiry_delta: (6 << 4) | 2,
2405 htlc_minimum_msat: 0,
2406 htlc_maximum_msat: MAX_VALUE_MSAT,
2408 fee_proportional_millionths: 0,
2409 excess_data: Vec::new(),
2412 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2413 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2414 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2415 short_channel_id: 11,
2418 cltv_expiry_delta: (11 << 4) | 1,
2419 htlc_minimum_msat: 0,
2420 htlc_maximum_msat: MAX_VALUE_MSAT,
2422 fee_proportional_millionths: 0,
2423 excess_data: Vec::new()
2425 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2426 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2427 short_channel_id: 11,
2430 cltv_expiry_delta: (11 << 4) | 2,
2431 htlc_minimum_msat: 0,
2432 htlc_maximum_msat: MAX_VALUE_MSAT,
2434 fee_proportional_millionths: 0,
2435 excess_data: Vec::new()
2438 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2440 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2442 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2443 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2444 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2445 short_channel_id: 7,
2448 cltv_expiry_delta: (7 << 4) | 1,
2449 htlc_minimum_msat: 0,
2450 htlc_maximum_msat: MAX_VALUE_MSAT,
2452 fee_proportional_millionths: 1000000,
2453 excess_data: Vec::new()
2455 update_channel(&gossip_sync, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2456 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2457 short_channel_id: 7,
2460 cltv_expiry_delta: (7 << 4) | 2,
2461 htlc_minimum_msat: 0,
2462 htlc_maximum_msat: MAX_VALUE_MSAT,
2464 fee_proportional_millionths: 0,
2465 excess_data: Vec::new()
2468 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2470 (secp_ctx, network_graph, gossip_sync, chain_monitor, logger)
2474 fn simple_route_test() {
2475 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2476 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2477 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2478 let scorer = test_utils::TestScorer::with_penalty(0);
2479 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2480 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2482 // Simple route to 2 via 1
2484 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) {
2485 assert_eq!(err, "Cannot send a payment of 0 msat");
2486 } else { panic!(); }
2488 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2489 assert_eq!(route.paths[0].len(), 2);
2491 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2492 assert_eq!(route.paths[0][0].short_channel_id, 2);
2493 assert_eq!(route.paths[0][0].fee_msat, 100);
2494 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2495 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2496 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2498 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2499 assert_eq!(route.paths[0][1].short_channel_id, 4);
2500 assert_eq!(route.paths[0][1].fee_msat, 100);
2501 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2502 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2503 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2507 fn invalid_first_hop_test() {
2508 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2509 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2510 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2511 let scorer = test_utils::TestScorer::with_penalty(0);
2512 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2513 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2515 // Simple route to 2 via 1
2517 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2519 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2520 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) {
2521 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2522 } else { panic!(); }
2524 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2525 assert_eq!(route.paths[0].len(), 2);
2529 fn htlc_minimum_test() {
2530 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2531 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2532 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2533 let scorer = test_utils::TestScorer::with_penalty(0);
2534 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2535 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2537 // Simple route to 2 via 1
2539 // Disable other paths
2540 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2541 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2542 short_channel_id: 12,
2544 flags: 2, // to disable
2545 cltv_expiry_delta: 0,
2546 htlc_minimum_msat: 0,
2547 htlc_maximum_msat: MAX_VALUE_MSAT,
2549 fee_proportional_millionths: 0,
2550 excess_data: Vec::new()
2552 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2553 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2554 short_channel_id: 3,
2556 flags: 2, // to disable
2557 cltv_expiry_delta: 0,
2558 htlc_minimum_msat: 0,
2559 htlc_maximum_msat: MAX_VALUE_MSAT,
2561 fee_proportional_millionths: 0,
2562 excess_data: Vec::new()
2564 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2565 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2566 short_channel_id: 13,
2568 flags: 2, // to disable
2569 cltv_expiry_delta: 0,
2570 htlc_minimum_msat: 0,
2571 htlc_maximum_msat: MAX_VALUE_MSAT,
2573 fee_proportional_millionths: 0,
2574 excess_data: Vec::new()
2576 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2577 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2578 short_channel_id: 6,
2580 flags: 2, // to disable
2581 cltv_expiry_delta: 0,
2582 htlc_minimum_msat: 0,
2583 htlc_maximum_msat: MAX_VALUE_MSAT,
2585 fee_proportional_millionths: 0,
2586 excess_data: Vec::new()
2588 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2589 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2590 short_channel_id: 7,
2592 flags: 2, // to disable
2593 cltv_expiry_delta: 0,
2594 htlc_minimum_msat: 0,
2595 htlc_maximum_msat: MAX_VALUE_MSAT,
2597 fee_proportional_millionths: 0,
2598 excess_data: Vec::new()
2601 // Check against amount_to_transfer_over_msat.
2602 // Set minimal HTLC of 200_000_000 msat.
2603 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2604 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2605 short_channel_id: 2,
2608 cltv_expiry_delta: 0,
2609 htlc_minimum_msat: 200_000_000,
2610 htlc_maximum_msat: MAX_VALUE_MSAT,
2612 fee_proportional_millionths: 0,
2613 excess_data: Vec::new()
2616 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2618 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2619 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2620 short_channel_id: 4,
2623 cltv_expiry_delta: 0,
2624 htlc_minimum_msat: 0,
2625 htlc_maximum_msat: 199_999_999,
2627 fee_proportional_millionths: 0,
2628 excess_data: Vec::new()
2631 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2632 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) {
2633 assert_eq!(err, "Failed to find a path to the given destination");
2634 } else { panic!(); }
2636 // Lift the restriction on the first hop.
2637 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2638 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2639 short_channel_id: 2,
2642 cltv_expiry_delta: 0,
2643 htlc_minimum_msat: 0,
2644 htlc_maximum_msat: MAX_VALUE_MSAT,
2646 fee_proportional_millionths: 0,
2647 excess_data: Vec::new()
2650 // A payment above the minimum should pass
2651 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();
2652 assert_eq!(route.paths[0].len(), 2);
2656 fn htlc_minimum_overpay_test() {
2657 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2658 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2659 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
2660 let scorer = test_utils::TestScorer::with_penalty(0);
2661 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2662 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2664 // A route to node#2 via two paths.
2665 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2666 // Thus, they can't send 60 without overpaying.
2667 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2668 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2669 short_channel_id: 2,
2672 cltv_expiry_delta: 0,
2673 htlc_minimum_msat: 35_000,
2674 htlc_maximum_msat: 40_000,
2676 fee_proportional_millionths: 0,
2677 excess_data: Vec::new()
2679 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2680 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2681 short_channel_id: 12,
2684 cltv_expiry_delta: 0,
2685 htlc_minimum_msat: 35_000,
2686 htlc_maximum_msat: 40_000,
2688 fee_proportional_millionths: 0,
2689 excess_data: Vec::new()
2693 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2694 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2695 short_channel_id: 13,
2698 cltv_expiry_delta: 0,
2699 htlc_minimum_msat: 0,
2700 htlc_maximum_msat: MAX_VALUE_MSAT,
2702 fee_proportional_millionths: 0,
2703 excess_data: Vec::new()
2705 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2706 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2707 short_channel_id: 4,
2710 cltv_expiry_delta: 0,
2711 htlc_minimum_msat: 0,
2712 htlc_maximum_msat: MAX_VALUE_MSAT,
2714 fee_proportional_millionths: 0,
2715 excess_data: Vec::new()
2718 // Disable other paths
2719 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2720 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2721 short_channel_id: 1,
2723 flags: 2, // to disable
2724 cltv_expiry_delta: 0,
2725 htlc_minimum_msat: 0,
2726 htlc_maximum_msat: MAX_VALUE_MSAT,
2728 fee_proportional_millionths: 0,
2729 excess_data: Vec::new()
2732 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2733 // Overpay fees to hit htlc_minimum_msat.
2734 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2735 // TODO: this could be better balanced to overpay 10k and not 15k.
2736 assert_eq!(overpaid_fees, 15_000);
2738 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2739 // while taking even more fee to match htlc_minimum_msat.
2740 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2741 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2742 short_channel_id: 12,
2745 cltv_expiry_delta: 0,
2746 htlc_minimum_msat: 65_000,
2747 htlc_maximum_msat: 80_000,
2749 fee_proportional_millionths: 0,
2750 excess_data: Vec::new()
2752 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2753 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2754 short_channel_id: 2,
2757 cltv_expiry_delta: 0,
2758 htlc_minimum_msat: 0,
2759 htlc_maximum_msat: MAX_VALUE_MSAT,
2761 fee_proportional_millionths: 0,
2762 excess_data: Vec::new()
2764 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2765 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2766 short_channel_id: 4,
2769 cltv_expiry_delta: 0,
2770 htlc_minimum_msat: 0,
2771 htlc_maximum_msat: MAX_VALUE_MSAT,
2773 fee_proportional_millionths: 100_000,
2774 excess_data: Vec::new()
2777 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2778 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2779 assert_eq!(route.paths.len(), 1);
2780 assert_eq!(route.paths[0][0].short_channel_id, 12);
2781 let fees = route.paths[0][0].fee_msat;
2782 assert_eq!(fees, 5_000);
2784 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2785 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2786 // the other channel.
2787 assert_eq!(route.paths.len(), 1);
2788 assert_eq!(route.paths[0][0].short_channel_id, 2);
2789 let fees = route.paths[0][0].fee_msat;
2790 assert_eq!(fees, 5_000);
2794 fn disable_channels_test() {
2795 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2796 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2797 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2798 let scorer = test_utils::TestScorer::with_penalty(0);
2799 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2800 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2802 // // Disable channels 4 and 12 by flags=2
2803 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2804 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2805 short_channel_id: 4,
2807 flags: 2, // to disable
2808 cltv_expiry_delta: 0,
2809 htlc_minimum_msat: 0,
2810 htlc_maximum_msat: MAX_VALUE_MSAT,
2812 fee_proportional_millionths: 0,
2813 excess_data: Vec::new()
2815 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2816 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2817 short_channel_id: 12,
2819 flags: 2, // to disable
2820 cltv_expiry_delta: 0,
2821 htlc_minimum_msat: 0,
2822 htlc_maximum_msat: MAX_VALUE_MSAT,
2824 fee_proportional_millionths: 0,
2825 excess_data: Vec::new()
2828 // If all the channels require some features we don't understand, route should fail
2829 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) {
2830 assert_eq!(err, "Failed to find a path to the given destination");
2831 } else { panic!(); }
2833 // If we specify a channel to node7, that overrides our local channel view and that gets used
2834 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2835 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();
2836 assert_eq!(route.paths[0].len(), 2);
2838 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2839 assert_eq!(route.paths[0][0].short_channel_id, 42);
2840 assert_eq!(route.paths[0][0].fee_msat, 200);
2841 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2842 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2843 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2845 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2846 assert_eq!(route.paths[0][1].short_channel_id, 13);
2847 assert_eq!(route.paths[0][1].fee_msat, 100);
2848 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2849 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2850 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2854 fn disable_node_test() {
2855 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2856 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2857 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2858 let scorer = test_utils::TestScorer::with_penalty(0);
2859 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2860 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2862 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2863 let mut unknown_features = NodeFeatures::empty();
2864 unknown_features.set_unknown_feature_required();
2865 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2866 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2867 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2869 // If all nodes 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));
2893 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2894 // naively) assume that the user checked the feature bits on the invoice, which override
2895 // the node_announcement.
2899 fn our_chans_test() {
2900 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2901 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2902 let scorer = test_utils::TestScorer::with_penalty(0);
2903 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2904 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2906 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2907 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2908 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2909 assert_eq!(route.paths[0].len(), 3);
2911 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2912 assert_eq!(route.paths[0][0].short_channel_id, 2);
2913 assert_eq!(route.paths[0][0].fee_msat, 200);
2914 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2915 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2916 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2918 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2919 assert_eq!(route.paths[0][1].short_channel_id, 4);
2920 assert_eq!(route.paths[0][1].fee_msat, 100);
2921 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2922 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2923 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2925 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2926 assert_eq!(route.paths[0][2].short_channel_id, 3);
2927 assert_eq!(route.paths[0][2].fee_msat, 100);
2928 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2929 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2930 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2932 // If we specify a channel to node7, that overrides our local channel view and that gets used
2933 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2934 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2935 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();
2936 assert_eq!(route.paths[0].len(), 2);
2938 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2939 assert_eq!(route.paths[0][0].short_channel_id, 42);
2940 assert_eq!(route.paths[0][0].fee_msat, 200);
2941 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2942 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2943 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2945 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2946 assert_eq!(route.paths[0][1].short_channel_id, 13);
2947 assert_eq!(route.paths[0][1].fee_msat, 100);
2948 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2949 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2950 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2953 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2954 let zero_fees = RoutingFees {
2956 proportional_millionths: 0,
2958 vec![RouteHint(vec![RouteHintHop {
2959 src_node_id: nodes[3],
2960 short_channel_id: 8,
2962 cltv_expiry_delta: (8 << 4) | 1,
2963 htlc_minimum_msat: None,
2964 htlc_maximum_msat: None,
2966 ]), RouteHint(vec![RouteHintHop {
2967 src_node_id: nodes[4],
2968 short_channel_id: 9,
2971 proportional_millionths: 0,
2973 cltv_expiry_delta: (9 << 4) | 1,
2974 htlc_minimum_msat: None,
2975 htlc_maximum_msat: None,
2976 }]), RouteHint(vec![RouteHintHop {
2977 src_node_id: nodes[5],
2978 short_channel_id: 10,
2980 cltv_expiry_delta: (10 << 4) | 1,
2981 htlc_minimum_msat: None,
2982 htlc_maximum_msat: None,
2986 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2987 let zero_fees = RoutingFees {
2989 proportional_millionths: 0,
2991 vec![RouteHint(vec![RouteHintHop {
2992 src_node_id: nodes[2],
2993 short_channel_id: 5,
2996 proportional_millionths: 0,
2998 cltv_expiry_delta: (5 << 4) | 1,
2999 htlc_minimum_msat: None,
3000 htlc_maximum_msat: None,
3002 src_node_id: nodes[3],
3003 short_channel_id: 8,
3005 cltv_expiry_delta: (8 << 4) | 1,
3006 htlc_minimum_msat: None,
3007 htlc_maximum_msat: None,
3009 ]), RouteHint(vec![RouteHintHop {
3010 src_node_id: nodes[4],
3011 short_channel_id: 9,
3014 proportional_millionths: 0,
3016 cltv_expiry_delta: (9 << 4) | 1,
3017 htlc_minimum_msat: None,
3018 htlc_maximum_msat: None,
3019 }]), RouteHint(vec![RouteHintHop {
3020 src_node_id: nodes[5],
3021 short_channel_id: 10,
3023 cltv_expiry_delta: (10 << 4) | 1,
3024 htlc_minimum_msat: None,
3025 htlc_maximum_msat: None,
3030 fn partial_route_hint_test() {
3031 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3032 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3033 let scorer = test_utils::TestScorer::with_penalty(0);
3034 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3035 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3037 // Simple test across 2, 3, 5, and 4 via a last_hop channel
3038 // Tests the behaviour when the RouteHint contains a suboptimal hop.
3039 // RouteHint may be partially used by the algo to build the best path.
3041 // First check that last hop can't have its source as the payee.
3042 let invalid_last_hop = RouteHint(vec![RouteHintHop {
3043 src_node_id: nodes[6],
3044 short_channel_id: 8,
3047 proportional_millionths: 0,
3049 cltv_expiry_delta: (8 << 4) | 1,
3050 htlc_minimum_msat: None,
3051 htlc_maximum_msat: None,
3054 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
3055 invalid_last_hops.push(invalid_last_hop);
3057 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
3058 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) {
3059 assert_eq!(err, "Route hint cannot have the payee as the source.");
3060 } else { panic!(); }
3063 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
3064 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3065 assert_eq!(route.paths[0].len(), 5);
3067 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3068 assert_eq!(route.paths[0][0].short_channel_id, 2);
3069 assert_eq!(route.paths[0][0].fee_msat, 100);
3070 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3071 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3072 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3074 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3075 assert_eq!(route.paths[0][1].short_channel_id, 4);
3076 assert_eq!(route.paths[0][1].fee_msat, 0);
3077 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3078 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3079 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3081 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3082 assert_eq!(route.paths[0][2].short_channel_id, 6);
3083 assert_eq!(route.paths[0][2].fee_msat, 0);
3084 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3085 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3086 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3088 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3089 assert_eq!(route.paths[0][3].short_channel_id, 11);
3090 assert_eq!(route.paths[0][3].fee_msat, 0);
3091 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3092 // If we have a peer in the node map, we'll use their features here since we don't have
3093 // a way of figuring out their features from the invoice:
3094 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3095 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3097 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3098 assert_eq!(route.paths[0][4].short_channel_id, 8);
3099 assert_eq!(route.paths[0][4].fee_msat, 100);
3100 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3101 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3102 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3105 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3106 let zero_fees = RoutingFees {
3108 proportional_millionths: 0,
3110 vec![RouteHint(vec![RouteHintHop {
3111 src_node_id: nodes[3],
3112 short_channel_id: 8,
3114 cltv_expiry_delta: (8 << 4) | 1,
3115 htlc_minimum_msat: None,
3116 htlc_maximum_msat: None,
3117 }]), RouteHint(vec![
3119 ]), RouteHint(vec![RouteHintHop {
3120 src_node_id: nodes[5],
3121 short_channel_id: 10,
3123 cltv_expiry_delta: (10 << 4) | 1,
3124 htlc_minimum_msat: None,
3125 htlc_maximum_msat: None,
3130 fn ignores_empty_last_hops_test() {
3131 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3132 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3133 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
3134 let scorer = test_utils::TestScorer::with_penalty(0);
3135 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3136 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3138 // Test handling of an empty RouteHint passed in Invoice.
3140 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3141 assert_eq!(route.paths[0].len(), 5);
3143 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3144 assert_eq!(route.paths[0][0].short_channel_id, 2);
3145 assert_eq!(route.paths[0][0].fee_msat, 100);
3146 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3147 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3148 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3150 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3151 assert_eq!(route.paths[0][1].short_channel_id, 4);
3152 assert_eq!(route.paths[0][1].fee_msat, 0);
3153 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3154 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3155 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3157 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3158 assert_eq!(route.paths[0][2].short_channel_id, 6);
3159 assert_eq!(route.paths[0][2].fee_msat, 0);
3160 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3161 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3162 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3164 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3165 assert_eq!(route.paths[0][3].short_channel_id, 11);
3166 assert_eq!(route.paths[0][3].fee_msat, 0);
3167 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3168 // If we have a peer in the node map, we'll use their features here since we don't have
3169 // a way of figuring out their features from the invoice:
3170 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3171 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3173 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3174 assert_eq!(route.paths[0][4].short_channel_id, 8);
3175 assert_eq!(route.paths[0][4].fee_msat, 100);
3176 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3177 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3178 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3181 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3183 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3184 let zero_fees = RoutingFees {
3186 proportional_millionths: 0,
3188 vec![RouteHint(vec![RouteHintHop {
3189 src_node_id: hint_hops[0],
3190 short_channel_id: 0xff00,
3193 proportional_millionths: 0,
3195 cltv_expiry_delta: (5 << 4) | 1,
3196 htlc_minimum_msat: None,
3197 htlc_maximum_msat: None,
3199 src_node_id: hint_hops[1],
3200 short_channel_id: 0xff01,
3202 cltv_expiry_delta: (8 << 4) | 1,
3203 htlc_minimum_msat: None,
3204 htlc_maximum_msat: None,
3209 fn multi_hint_last_hops_test() {
3210 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3211 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3212 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3213 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3214 let scorer = test_utils::TestScorer::with_penalty(0);
3215 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3216 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3217 // Test through channels 2, 3, 0xff00, 0xff01.
3218 // Test shows that multiple hop hints are considered.
3220 // Disabling channels 6 & 7 by flags=2
3221 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3222 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3223 short_channel_id: 6,
3225 flags: 2, // to disable
3226 cltv_expiry_delta: 0,
3227 htlc_minimum_msat: 0,
3228 htlc_maximum_msat: MAX_VALUE_MSAT,
3230 fee_proportional_millionths: 0,
3231 excess_data: Vec::new()
3233 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3234 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3235 short_channel_id: 7,
3237 flags: 2, // to disable
3238 cltv_expiry_delta: 0,
3239 htlc_minimum_msat: 0,
3240 htlc_maximum_msat: MAX_VALUE_MSAT,
3242 fee_proportional_millionths: 0,
3243 excess_data: Vec::new()
3246 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3247 assert_eq!(route.paths[0].len(), 4);
3249 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3250 assert_eq!(route.paths[0][0].short_channel_id, 2);
3251 assert_eq!(route.paths[0][0].fee_msat, 200);
3252 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3253 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3254 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3256 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3257 assert_eq!(route.paths[0][1].short_channel_id, 4);
3258 assert_eq!(route.paths[0][1].fee_msat, 100);
3259 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3260 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3261 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3263 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
3264 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3265 assert_eq!(route.paths[0][2].fee_msat, 0);
3266 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3267 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
3268 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3270 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3271 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3272 assert_eq!(route.paths[0][3].fee_msat, 100);
3273 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3274 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3275 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3279 fn private_multi_hint_last_hops_test() {
3280 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3281 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3283 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3284 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3286 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3287 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3288 let scorer = test_utils::TestScorer::with_penalty(0);
3289 // Test through channels 2, 3, 0xff00, 0xff01.
3290 // Test shows that multiple hop hints are considered.
3292 // Disabling channels 6 & 7 by flags=2
3293 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3294 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3295 short_channel_id: 6,
3297 flags: 2, // to disable
3298 cltv_expiry_delta: 0,
3299 htlc_minimum_msat: 0,
3300 htlc_maximum_msat: MAX_VALUE_MSAT,
3302 fee_proportional_millionths: 0,
3303 excess_data: Vec::new()
3305 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3306 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3307 short_channel_id: 7,
3309 flags: 2, // to disable
3310 cltv_expiry_delta: 0,
3311 htlc_minimum_msat: 0,
3312 htlc_maximum_msat: MAX_VALUE_MSAT,
3314 fee_proportional_millionths: 0,
3315 excess_data: Vec::new()
3318 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3319 assert_eq!(route.paths[0].len(), 4);
3321 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3322 assert_eq!(route.paths[0][0].short_channel_id, 2);
3323 assert_eq!(route.paths[0][0].fee_msat, 200);
3324 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3325 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3326 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3328 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3329 assert_eq!(route.paths[0][1].short_channel_id, 4);
3330 assert_eq!(route.paths[0][1].fee_msat, 100);
3331 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3332 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3333 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3335 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3336 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3337 assert_eq!(route.paths[0][2].fee_msat, 0);
3338 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3339 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3340 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3342 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3343 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3344 assert_eq!(route.paths[0][3].fee_msat, 100);
3345 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3346 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3347 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3350 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3351 let zero_fees = RoutingFees {
3353 proportional_millionths: 0,
3355 vec![RouteHint(vec![RouteHintHop {
3356 src_node_id: nodes[4],
3357 short_channel_id: 11,
3359 cltv_expiry_delta: (11 << 4) | 1,
3360 htlc_minimum_msat: None,
3361 htlc_maximum_msat: None,
3363 src_node_id: nodes[3],
3364 short_channel_id: 8,
3366 cltv_expiry_delta: (8 << 4) | 1,
3367 htlc_minimum_msat: None,
3368 htlc_maximum_msat: None,
3369 }]), RouteHint(vec![RouteHintHop {
3370 src_node_id: nodes[4],
3371 short_channel_id: 9,
3374 proportional_millionths: 0,
3376 cltv_expiry_delta: (9 << 4) | 1,
3377 htlc_minimum_msat: None,
3378 htlc_maximum_msat: None,
3379 }]), RouteHint(vec![RouteHintHop {
3380 src_node_id: nodes[5],
3381 short_channel_id: 10,
3383 cltv_expiry_delta: (10 << 4) | 1,
3384 htlc_minimum_msat: None,
3385 htlc_maximum_msat: None,
3390 fn last_hops_with_public_channel_test() {
3391 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3392 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3393 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3394 let scorer = test_utils::TestScorer::with_penalty(0);
3395 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3396 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3397 // This test shows that public routes can be present in the invoice
3398 // which would be handled in the same manner.
3400 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3401 assert_eq!(route.paths[0].len(), 5);
3403 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3404 assert_eq!(route.paths[0][0].short_channel_id, 2);
3405 assert_eq!(route.paths[0][0].fee_msat, 100);
3406 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3407 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3408 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3410 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3411 assert_eq!(route.paths[0][1].short_channel_id, 4);
3412 assert_eq!(route.paths[0][1].fee_msat, 0);
3413 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3414 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3415 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3417 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3418 assert_eq!(route.paths[0][2].short_channel_id, 6);
3419 assert_eq!(route.paths[0][2].fee_msat, 0);
3420 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3421 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3422 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3424 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3425 assert_eq!(route.paths[0][3].short_channel_id, 11);
3426 assert_eq!(route.paths[0][3].fee_msat, 0);
3427 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3428 // If we have a peer in the node map, we'll use their features here since we don't have
3429 // a way of figuring out their features from the invoice:
3430 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3431 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3433 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3434 assert_eq!(route.paths[0][4].short_channel_id, 8);
3435 assert_eq!(route.paths[0][4].fee_msat, 100);
3436 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3437 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3438 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3442 fn our_chans_last_hop_connect_test() {
3443 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3444 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3445 let scorer = test_utils::TestScorer::with_penalty(0);
3446 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3447 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3449 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3450 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3451 let mut last_hops = last_hops(&nodes);
3452 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3453 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();
3454 assert_eq!(route.paths[0].len(), 2);
3456 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3457 assert_eq!(route.paths[0][0].short_channel_id, 42);
3458 assert_eq!(route.paths[0][0].fee_msat, 0);
3459 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3460 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3461 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3463 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3464 assert_eq!(route.paths[0][1].short_channel_id, 8);
3465 assert_eq!(route.paths[0][1].fee_msat, 100);
3466 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3467 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3468 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3470 last_hops[0].0[0].fees.base_msat = 1000;
3472 // Revert to via 6 as the fee on 8 goes up
3473 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3474 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3475 assert_eq!(route.paths[0].len(), 4);
3477 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3478 assert_eq!(route.paths[0][0].short_channel_id, 2);
3479 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3480 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3481 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3482 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3484 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3485 assert_eq!(route.paths[0][1].short_channel_id, 4);
3486 assert_eq!(route.paths[0][1].fee_msat, 100);
3487 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3488 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3489 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3491 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3492 assert_eq!(route.paths[0][2].short_channel_id, 7);
3493 assert_eq!(route.paths[0][2].fee_msat, 0);
3494 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3495 // If we have a peer in the node map, we'll use their features here since we don't have
3496 // a way of figuring out their features from the invoice:
3497 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3498 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3500 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3501 assert_eq!(route.paths[0][3].short_channel_id, 10);
3502 assert_eq!(route.paths[0][3].fee_msat, 100);
3503 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3504 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3505 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3507 // ...but still use 8 for larger payments as 6 has a variable feerate
3508 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3509 assert_eq!(route.paths[0].len(), 5);
3511 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3512 assert_eq!(route.paths[0][0].short_channel_id, 2);
3513 assert_eq!(route.paths[0][0].fee_msat, 3000);
3514 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3515 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3516 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3518 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3519 assert_eq!(route.paths[0][1].short_channel_id, 4);
3520 assert_eq!(route.paths[0][1].fee_msat, 0);
3521 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3522 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3523 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3525 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3526 assert_eq!(route.paths[0][2].short_channel_id, 6);
3527 assert_eq!(route.paths[0][2].fee_msat, 0);
3528 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3529 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3530 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3532 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3533 assert_eq!(route.paths[0][3].short_channel_id, 11);
3534 assert_eq!(route.paths[0][3].fee_msat, 1000);
3535 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 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][3].node_features.le_flags(), &id_to_feature_flags(4));
3539 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3541 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3542 assert_eq!(route.paths[0][4].short_channel_id, 8);
3543 assert_eq!(route.paths[0][4].fee_msat, 2000);
3544 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3545 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3546 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3549 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> {
3550 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3551 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3552 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3554 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3555 let last_hops = RouteHint(vec![RouteHintHop {
3556 src_node_id: middle_node_id,
3557 short_channel_id: 8,
3560 proportional_millionths: last_hop_fee_prop,
3562 cltv_expiry_delta: (8 << 4) | 1,
3563 htlc_minimum_msat: None,
3564 htlc_maximum_msat: last_hop_htlc_max,
3566 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3567 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3568 let scorer = test_utils::TestScorer::with_penalty(0);
3569 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3570 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3571 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
3572 let logger = test_utils::TestLogger::new();
3573 let network_graph = NetworkGraph::new(genesis_hash, &logger);
3574 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3575 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
3580 fn unannounced_path_test() {
3581 // We should be able to send a payment to a destination without any help of a routing graph
3582 // if we have a channel with a common counterparty that appears in the first and last hop
3584 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3586 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3587 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3588 assert_eq!(route.paths[0].len(), 2);
3590 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3591 assert_eq!(route.paths[0][0].short_channel_id, 42);
3592 assert_eq!(route.paths[0][0].fee_msat, 1001);
3593 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3594 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3595 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3597 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3598 assert_eq!(route.paths[0][1].short_channel_id, 8);
3599 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3600 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3601 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3602 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3606 fn overflow_unannounced_path_test_liquidity_underflow() {
3607 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3608 // the last-hop had a fee which overflowed a u64, we'd panic.
3609 // This was due to us adding the first-hop from us unconditionally, causing us to think
3610 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3611 // In this test, we previously hit a subtraction underflow due to having less available
3612 // liquidity at the last hop than 0.
3613 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());
3617 fn overflow_unannounced_path_test_feerate_overflow() {
3618 // This tests for the same case as above, except instead of hitting a subtraction
3619 // underflow, we hit a case where the fee charged at a hop overflowed.
3620 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());
3624 fn available_amount_while_routing_test() {
3625 // Tests whether we choose the correct available channel amount while routing.
3627 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3628 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3629 let scorer = test_utils::TestScorer::with_penalty(0);
3630 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3631 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3632 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
3634 // We will use a simple single-path route from
3635 // our node to node2 via node0: channels {1, 3}.
3637 // First disable all other paths.
3638 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3639 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3640 short_channel_id: 2,
3643 cltv_expiry_delta: 0,
3644 htlc_minimum_msat: 0,
3645 htlc_maximum_msat: 100_000,
3647 fee_proportional_millionths: 0,
3648 excess_data: Vec::new()
3650 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3651 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3652 short_channel_id: 12,
3655 cltv_expiry_delta: 0,
3656 htlc_minimum_msat: 0,
3657 htlc_maximum_msat: 100_000,
3659 fee_proportional_millionths: 0,
3660 excess_data: Vec::new()
3663 // Make the first channel (#1) very permissive,
3664 // and we will be testing all limits on the second channel.
3665 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3666 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3667 short_channel_id: 1,
3670 cltv_expiry_delta: 0,
3671 htlc_minimum_msat: 0,
3672 htlc_maximum_msat: 1_000_000_000,
3674 fee_proportional_millionths: 0,
3675 excess_data: Vec::new()
3678 // First, let's see if routing works if we have absolutely no idea about the available amount.
3679 // In this case, it should be set to 250_000 sats.
3680 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3681 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3682 short_channel_id: 3,
3685 cltv_expiry_delta: 0,
3686 htlc_minimum_msat: 0,
3687 htlc_maximum_msat: 250_000_000,
3689 fee_proportional_millionths: 0,
3690 excess_data: Vec::new()
3694 // Attempt to route more than available results in a failure.
3695 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3696 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3697 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3698 } else { panic!(); }
3702 // Now, attempt to route an exact amount we have should be fine.
3703 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();
3704 assert_eq!(route.paths.len(), 1);
3705 let path = route.paths.last().unwrap();
3706 assert_eq!(path.len(), 2);
3707 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3708 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3711 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3712 // Disable channel #1 and use another first hop.
3713 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3714 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3715 short_channel_id: 1,
3718 cltv_expiry_delta: 0,
3719 htlc_minimum_msat: 0,
3720 htlc_maximum_msat: 1_000_000_000,
3722 fee_proportional_millionths: 0,
3723 excess_data: Vec::new()
3726 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3727 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3730 // Attempt to route more than available results in a failure.
3731 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3732 &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) {
3733 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3734 } else { panic!(); }
3738 // Now, attempt to route an exact amount we have should be fine.
3739 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();
3740 assert_eq!(route.paths.len(), 1);
3741 let path = route.paths.last().unwrap();
3742 assert_eq!(path.len(), 2);
3743 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3744 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3747 // Enable channel #1 back.
3748 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3749 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3750 short_channel_id: 1,
3753 cltv_expiry_delta: 0,
3754 htlc_minimum_msat: 0,
3755 htlc_maximum_msat: 1_000_000_000,
3757 fee_proportional_millionths: 0,
3758 excess_data: Vec::new()
3762 // Now let's see if routing works if we know only htlc_maximum_msat.
3763 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3764 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3765 short_channel_id: 3,
3768 cltv_expiry_delta: 0,
3769 htlc_minimum_msat: 0,
3770 htlc_maximum_msat: 15_000,
3772 fee_proportional_millionths: 0,
3773 excess_data: Vec::new()
3777 // Attempt to route more than available results in a failure.
3778 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3779 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3780 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3781 } else { panic!(); }
3785 // Now, attempt to route an exact amount we have should be fine.
3786 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3787 assert_eq!(route.paths.len(), 1);
3788 let path = route.paths.last().unwrap();
3789 assert_eq!(path.len(), 2);
3790 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3791 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3794 // Now let's see if routing works if we know only capacity from the UTXO.
3796 // We can't change UTXO capacity on the fly, so we'll disable
3797 // the existing channel and add another one with the capacity we need.
3798 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3799 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3800 short_channel_id: 3,
3803 cltv_expiry_delta: 0,
3804 htlc_minimum_msat: 0,
3805 htlc_maximum_msat: MAX_VALUE_MSAT,
3807 fee_proportional_millionths: 0,
3808 excess_data: Vec::new()
3811 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3812 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3813 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3814 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3815 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3817 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3818 gossip_sync.add_chain_access(Some(chain_monitor));
3820 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3821 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3822 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3823 short_channel_id: 333,
3826 cltv_expiry_delta: (3 << 4) | 1,
3827 htlc_minimum_msat: 0,
3828 htlc_maximum_msat: 15_000,
3830 fee_proportional_millionths: 0,
3831 excess_data: Vec::new()
3833 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3834 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3835 short_channel_id: 333,
3838 cltv_expiry_delta: (3 << 4) | 2,
3839 htlc_minimum_msat: 0,
3840 htlc_maximum_msat: 15_000,
3842 fee_proportional_millionths: 0,
3843 excess_data: Vec::new()
3847 // Attempt to route more than available results in a failure.
3848 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3849 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3850 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3851 } else { panic!(); }
3855 // Now, attempt to route an exact amount we have should be fine.
3856 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3857 assert_eq!(route.paths.len(), 1);
3858 let path = route.paths.last().unwrap();
3859 assert_eq!(path.len(), 2);
3860 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3861 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3864 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3865 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3866 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3867 short_channel_id: 333,
3870 cltv_expiry_delta: 0,
3871 htlc_minimum_msat: 0,
3872 htlc_maximum_msat: 10_000,
3874 fee_proportional_millionths: 0,
3875 excess_data: Vec::new()
3879 // Attempt to route more than available results in a failure.
3880 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3881 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3882 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3883 } else { panic!(); }
3887 // Now, attempt to route an exact amount we have should be fine.
3888 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3889 assert_eq!(route.paths.len(), 1);
3890 let path = route.paths.last().unwrap();
3891 assert_eq!(path.len(), 2);
3892 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3893 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3898 fn available_liquidity_last_hop_test() {
3899 // Check that available liquidity properly limits the path even when only
3900 // one of the latter hops is limited.
3901 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3902 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3903 let scorer = test_utils::TestScorer::with_penalty(0);
3904 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3905 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3906 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3908 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3909 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3910 // Total capacity: 50 sats.
3912 // Disable other potential paths.
3913 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3914 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3915 short_channel_id: 2,
3918 cltv_expiry_delta: 0,
3919 htlc_minimum_msat: 0,
3920 htlc_maximum_msat: 100_000,
3922 fee_proportional_millionths: 0,
3923 excess_data: Vec::new()
3925 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3926 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3927 short_channel_id: 7,
3930 cltv_expiry_delta: 0,
3931 htlc_minimum_msat: 0,
3932 htlc_maximum_msat: 100_000,
3934 fee_proportional_millionths: 0,
3935 excess_data: Vec::new()
3940 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3941 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3942 short_channel_id: 12,
3945 cltv_expiry_delta: 0,
3946 htlc_minimum_msat: 0,
3947 htlc_maximum_msat: 100_000,
3949 fee_proportional_millionths: 0,
3950 excess_data: Vec::new()
3952 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3953 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3954 short_channel_id: 13,
3957 cltv_expiry_delta: 0,
3958 htlc_minimum_msat: 0,
3959 htlc_maximum_msat: 100_000,
3961 fee_proportional_millionths: 0,
3962 excess_data: Vec::new()
3965 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3966 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3967 short_channel_id: 6,
3970 cltv_expiry_delta: 0,
3971 htlc_minimum_msat: 0,
3972 htlc_maximum_msat: 50_000,
3974 fee_proportional_millionths: 0,
3975 excess_data: Vec::new()
3977 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3978 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3979 short_channel_id: 11,
3982 cltv_expiry_delta: 0,
3983 htlc_minimum_msat: 0,
3984 htlc_maximum_msat: 100_000,
3986 fee_proportional_millionths: 0,
3987 excess_data: Vec::new()
3990 // Attempt to route more than available results in a failure.
3991 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3992 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3993 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3994 } else { panic!(); }
3998 // Now, attempt to route 49 sats (just a bit below the capacity).
3999 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4000 assert_eq!(route.paths.len(), 1);
4001 let mut total_amount_paid_msat = 0;
4002 for path in &route.paths {
4003 assert_eq!(path.len(), 4);
4004 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4005 total_amount_paid_msat += path.last().unwrap().fee_msat;
4007 assert_eq!(total_amount_paid_msat, 49_000);
4011 // Attempt to route an exact amount is also fine
4012 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4013 assert_eq!(route.paths.len(), 1);
4014 let mut total_amount_paid_msat = 0;
4015 for path in &route.paths {
4016 assert_eq!(path.len(), 4);
4017 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4018 total_amount_paid_msat += path.last().unwrap().fee_msat;
4020 assert_eq!(total_amount_paid_msat, 50_000);
4025 fn ignore_fee_first_hop_test() {
4026 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4027 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4028 let scorer = test_utils::TestScorer::with_penalty(0);
4029 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4030 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4031 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4033 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4034 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4035 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4036 short_channel_id: 1,
4039 cltv_expiry_delta: 0,
4040 htlc_minimum_msat: 0,
4041 htlc_maximum_msat: 100_000,
4042 fee_base_msat: 1_000_000,
4043 fee_proportional_millionths: 0,
4044 excess_data: Vec::new()
4046 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4047 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4048 short_channel_id: 3,
4051 cltv_expiry_delta: 0,
4052 htlc_minimum_msat: 0,
4053 htlc_maximum_msat: 50_000,
4055 fee_proportional_millionths: 0,
4056 excess_data: Vec::new()
4060 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4061 assert_eq!(route.paths.len(), 1);
4062 let mut total_amount_paid_msat = 0;
4063 for path in &route.paths {
4064 assert_eq!(path.len(), 2);
4065 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4066 total_amount_paid_msat += path.last().unwrap().fee_msat;
4068 assert_eq!(total_amount_paid_msat, 50_000);
4073 fn simple_mpp_route_test() {
4074 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4075 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4076 let scorer = test_utils::TestScorer::with_penalty(0);
4077 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4078 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4079 let payment_params = PaymentParameters::from_node_id(nodes[2])
4080 .with_features(channelmanager::provided_invoice_features());
4082 // We need a route consisting of 3 paths:
4083 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4084 // To achieve this, the amount being transferred should be around
4085 // the total capacity of these 3 paths.
4087 // First, we set limits on these (previously unlimited) channels.
4088 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
4090 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
4091 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4092 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4093 short_channel_id: 1,
4096 cltv_expiry_delta: 0,
4097 htlc_minimum_msat: 0,
4098 htlc_maximum_msat: 100_000,
4100 fee_proportional_millionths: 0,
4101 excess_data: Vec::new()
4103 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4104 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4105 short_channel_id: 3,
4108 cltv_expiry_delta: 0,
4109 htlc_minimum_msat: 0,
4110 htlc_maximum_msat: 50_000,
4112 fee_proportional_millionths: 0,
4113 excess_data: Vec::new()
4116 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
4117 // (total limit 60).
4118 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4119 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4120 short_channel_id: 12,
4123 cltv_expiry_delta: 0,
4124 htlc_minimum_msat: 0,
4125 htlc_maximum_msat: 60_000,
4127 fee_proportional_millionths: 0,
4128 excess_data: Vec::new()
4130 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4131 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4132 short_channel_id: 13,
4135 cltv_expiry_delta: 0,
4136 htlc_minimum_msat: 0,
4137 htlc_maximum_msat: 60_000,
4139 fee_proportional_millionths: 0,
4140 excess_data: Vec::new()
4143 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
4144 // (total capacity 180 sats).
4145 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4146 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4147 short_channel_id: 2,
4150 cltv_expiry_delta: 0,
4151 htlc_minimum_msat: 0,
4152 htlc_maximum_msat: 200_000,
4154 fee_proportional_millionths: 0,
4155 excess_data: Vec::new()
4157 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4158 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4159 short_channel_id: 4,
4162 cltv_expiry_delta: 0,
4163 htlc_minimum_msat: 0,
4164 htlc_maximum_msat: 180_000,
4166 fee_proportional_millionths: 0,
4167 excess_data: Vec::new()
4171 // Attempt to route more than available results in a failure.
4172 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4173 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42,
4174 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4175 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4176 } else { panic!(); }
4180 // Attempt to route while setting max_path_count to 0 results in a failure.
4181 let zero_payment_params = payment_params.clone().with_max_path_count(0);
4182 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4183 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100, 42,
4184 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4185 assert_eq!(err, "Can't find a route with no paths allowed.");
4186 } else { panic!(); }
4190 // Attempt to route while setting max_path_count to 3 results in a failure.
4191 // This is the case because the minimal_value_contribution_msat would require each path
4192 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
4193 let fail_payment_params = payment_params.clone().with_max_path_count(3);
4194 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4195 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000, 42,
4196 Arc::clone(&logger), &scorer, &random_seed_bytes) {
4197 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4198 } else { panic!(); }
4202 // Now, attempt to route 250 sats (just a bit below the capacity).
4203 // Our algorithm should provide us with these 3 paths.
4204 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4205 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4206 assert_eq!(route.paths.len(), 3);
4207 let mut total_amount_paid_msat = 0;
4208 for path in &route.paths {
4209 assert_eq!(path.len(), 2);
4210 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4211 total_amount_paid_msat += path.last().unwrap().fee_msat;
4213 assert_eq!(total_amount_paid_msat, 250_000);
4217 // Attempt to route an exact amount is also fine
4218 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
4219 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4220 assert_eq!(route.paths.len(), 3);
4221 let mut total_amount_paid_msat = 0;
4222 for path in &route.paths {
4223 assert_eq!(path.len(), 2);
4224 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4225 total_amount_paid_msat += path.last().unwrap().fee_msat;
4227 assert_eq!(total_amount_paid_msat, 290_000);
4232 fn long_mpp_route_test() {
4233 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4234 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4235 let scorer = test_utils::TestScorer::with_penalty(0);
4236 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4237 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4238 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4240 // We need a route consisting of 3 paths:
4241 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4242 // Note that these paths overlap (channels 5, 12, 13).
4243 // We will route 300 sats.
4244 // Each path will have 100 sats capacity, those channels which
4245 // are used twice will have 200 sats capacity.
4247 // Disable other potential paths.
4248 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4249 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4250 short_channel_id: 2,
4253 cltv_expiry_delta: 0,
4254 htlc_minimum_msat: 0,
4255 htlc_maximum_msat: 100_000,
4257 fee_proportional_millionths: 0,
4258 excess_data: Vec::new()
4260 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4261 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4262 short_channel_id: 7,
4265 cltv_expiry_delta: 0,
4266 htlc_minimum_msat: 0,
4267 htlc_maximum_msat: 100_000,
4269 fee_proportional_millionths: 0,
4270 excess_data: Vec::new()
4273 // Path via {node0, node2} is channels {1, 3, 5}.
4274 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4275 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4276 short_channel_id: 1,
4279 cltv_expiry_delta: 0,
4280 htlc_minimum_msat: 0,
4281 htlc_maximum_msat: 100_000,
4283 fee_proportional_millionths: 0,
4284 excess_data: Vec::new()
4286 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4287 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4288 short_channel_id: 3,
4291 cltv_expiry_delta: 0,
4292 htlc_minimum_msat: 0,
4293 htlc_maximum_msat: 100_000,
4295 fee_proportional_millionths: 0,
4296 excess_data: Vec::new()
4299 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4300 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4301 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4303 short_channel_id: 5,
4306 cltv_expiry_delta: 0,
4307 htlc_minimum_msat: 0,
4308 htlc_maximum_msat: 200_000,
4310 fee_proportional_millionths: 0,
4311 excess_data: Vec::new()
4314 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4315 // Add 100 sats to the capacities of {12, 13}, because these channels
4316 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4317 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4318 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4319 short_channel_id: 12,
4322 cltv_expiry_delta: 0,
4323 htlc_minimum_msat: 0,
4324 htlc_maximum_msat: 200_000,
4326 fee_proportional_millionths: 0,
4327 excess_data: Vec::new()
4329 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4330 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4331 short_channel_id: 13,
4334 cltv_expiry_delta: 0,
4335 htlc_minimum_msat: 0,
4336 htlc_maximum_msat: 200_000,
4338 fee_proportional_millionths: 0,
4339 excess_data: Vec::new()
4342 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4343 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4344 short_channel_id: 6,
4347 cltv_expiry_delta: 0,
4348 htlc_minimum_msat: 0,
4349 htlc_maximum_msat: 100_000,
4351 fee_proportional_millionths: 0,
4352 excess_data: Vec::new()
4354 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4355 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4356 short_channel_id: 11,
4359 cltv_expiry_delta: 0,
4360 htlc_minimum_msat: 0,
4361 htlc_maximum_msat: 100_000,
4363 fee_proportional_millionths: 0,
4364 excess_data: Vec::new()
4367 // Path via {node7, node2} is channels {12, 13, 5}.
4368 // We already limited them to 200 sats (they are used twice for 100 sats).
4369 // Nothing to do here.
4372 // Attempt to route more than available results in a failure.
4373 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4374 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4375 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4376 } else { panic!(); }
4380 // Now, attempt to route 300 sats (exact amount we can route).
4381 // Our algorithm should provide us with these 3 paths, 100 sats each.
4382 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4383 assert_eq!(route.paths.len(), 3);
4385 let mut total_amount_paid_msat = 0;
4386 for path in &route.paths {
4387 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4388 total_amount_paid_msat += path.last().unwrap().fee_msat;
4390 assert_eq!(total_amount_paid_msat, 300_000);
4396 fn mpp_cheaper_route_test() {
4397 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4398 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4399 let scorer = test_utils::TestScorer::with_penalty(0);
4400 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4401 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4402 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4404 // This test checks that if we have two cheaper paths and one more expensive path,
4405 // so that liquidity-wise any 2 of 3 combination is sufficient,
4406 // two cheaper paths will be taken.
4407 // These paths have equal available liquidity.
4409 // We need a combination of 3 paths:
4410 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4411 // Note that these paths overlap (channels 5, 12, 13).
4412 // Each path will have 100 sats capacity, those channels which
4413 // are used twice will have 200 sats capacity.
4415 // Disable other potential paths.
4416 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4417 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4418 short_channel_id: 2,
4421 cltv_expiry_delta: 0,
4422 htlc_minimum_msat: 0,
4423 htlc_maximum_msat: 100_000,
4425 fee_proportional_millionths: 0,
4426 excess_data: Vec::new()
4428 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4429 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4430 short_channel_id: 7,
4433 cltv_expiry_delta: 0,
4434 htlc_minimum_msat: 0,
4435 htlc_maximum_msat: 100_000,
4437 fee_proportional_millionths: 0,
4438 excess_data: Vec::new()
4441 // Path via {node0, node2} is channels {1, 3, 5}.
4442 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4443 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4444 short_channel_id: 1,
4447 cltv_expiry_delta: 0,
4448 htlc_minimum_msat: 0,
4449 htlc_maximum_msat: 100_000,
4451 fee_proportional_millionths: 0,
4452 excess_data: Vec::new()
4454 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4455 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4456 short_channel_id: 3,
4459 cltv_expiry_delta: 0,
4460 htlc_minimum_msat: 0,
4461 htlc_maximum_msat: 100_000,
4463 fee_proportional_millionths: 0,
4464 excess_data: Vec::new()
4467 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4468 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4469 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4471 short_channel_id: 5,
4474 cltv_expiry_delta: 0,
4475 htlc_minimum_msat: 0,
4476 htlc_maximum_msat: 200_000,
4478 fee_proportional_millionths: 0,
4479 excess_data: Vec::new()
4482 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4483 // Add 100 sats to the capacities of {12, 13}, because these channels
4484 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4485 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4486 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4487 short_channel_id: 12,
4490 cltv_expiry_delta: 0,
4491 htlc_minimum_msat: 0,
4492 htlc_maximum_msat: 200_000,
4494 fee_proportional_millionths: 0,
4495 excess_data: Vec::new()
4497 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4498 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4499 short_channel_id: 13,
4502 cltv_expiry_delta: 0,
4503 htlc_minimum_msat: 0,
4504 htlc_maximum_msat: 200_000,
4506 fee_proportional_millionths: 0,
4507 excess_data: Vec::new()
4510 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4511 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4512 short_channel_id: 6,
4515 cltv_expiry_delta: 0,
4516 htlc_minimum_msat: 0,
4517 htlc_maximum_msat: 100_000,
4518 fee_base_msat: 1_000,
4519 fee_proportional_millionths: 0,
4520 excess_data: Vec::new()
4522 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4523 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4524 short_channel_id: 11,
4527 cltv_expiry_delta: 0,
4528 htlc_minimum_msat: 0,
4529 htlc_maximum_msat: 100_000,
4531 fee_proportional_millionths: 0,
4532 excess_data: Vec::new()
4535 // Path via {node7, node2} is channels {12, 13, 5}.
4536 // We already limited them to 200 sats (they are used twice for 100 sats).
4537 // Nothing to do here.
4540 // Now, attempt to route 180 sats.
4541 // Our algorithm should provide us with these 2 paths.
4542 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4543 assert_eq!(route.paths.len(), 2);
4545 let mut total_value_transferred_msat = 0;
4546 let mut total_paid_msat = 0;
4547 for path in &route.paths {
4548 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4549 total_value_transferred_msat += path.last().unwrap().fee_msat;
4551 total_paid_msat += hop.fee_msat;
4554 // If we paid fee, this would be higher.
4555 assert_eq!(total_value_transferred_msat, 180_000);
4556 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4557 assert_eq!(total_fees_paid, 0);
4562 fn fees_on_mpp_route_test() {
4563 // This test makes sure that MPP algorithm properly takes into account
4564 // fees charged on the channels, by making the fees impactful:
4565 // if the fee is not properly accounted for, the behavior is different.
4566 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4567 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4568 let scorer = test_utils::TestScorer::with_penalty(0);
4569 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4570 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4571 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4573 // We need a route consisting of 2 paths:
4574 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4575 // We will route 200 sats, Each path will have 100 sats capacity.
4577 // This test is not particularly stable: e.g.,
4578 // there's a way to route via {node0, node2, node4}.
4579 // It works while pathfinding is deterministic, but can be broken otherwise.
4580 // It's fine to ignore this concern for now.
4582 // Disable other potential paths.
4583 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4584 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4585 short_channel_id: 2,
4588 cltv_expiry_delta: 0,
4589 htlc_minimum_msat: 0,
4590 htlc_maximum_msat: 100_000,
4592 fee_proportional_millionths: 0,
4593 excess_data: Vec::new()
4596 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4598 short_channel_id: 7,
4601 cltv_expiry_delta: 0,
4602 htlc_minimum_msat: 0,
4603 htlc_maximum_msat: 100_000,
4605 fee_proportional_millionths: 0,
4606 excess_data: Vec::new()
4609 // Path via {node0, node2} is channels {1, 3, 5}.
4610 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4611 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4612 short_channel_id: 1,
4615 cltv_expiry_delta: 0,
4616 htlc_minimum_msat: 0,
4617 htlc_maximum_msat: 100_000,
4619 fee_proportional_millionths: 0,
4620 excess_data: Vec::new()
4622 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4624 short_channel_id: 3,
4627 cltv_expiry_delta: 0,
4628 htlc_minimum_msat: 0,
4629 htlc_maximum_msat: 100_000,
4631 fee_proportional_millionths: 0,
4632 excess_data: Vec::new()
4635 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4636 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4637 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4638 short_channel_id: 5,
4641 cltv_expiry_delta: 0,
4642 htlc_minimum_msat: 0,
4643 htlc_maximum_msat: 100_000,
4645 fee_proportional_millionths: 0,
4646 excess_data: Vec::new()
4649 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4650 // All channels should be 100 sats capacity. But for the fee experiment,
4651 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4652 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4653 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4654 // so no matter how large are other channels,
4655 // the whole path will be limited by 100 sats with just these 2 conditions:
4656 // - channel 12 capacity is 250 sats
4657 // - fee for channel 6 is 150 sats
4658 // Let's test this by enforcing these 2 conditions and removing other limits.
4659 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4660 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4661 short_channel_id: 12,
4664 cltv_expiry_delta: 0,
4665 htlc_minimum_msat: 0,
4666 htlc_maximum_msat: 250_000,
4668 fee_proportional_millionths: 0,
4669 excess_data: Vec::new()
4671 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4672 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4673 short_channel_id: 13,
4676 cltv_expiry_delta: 0,
4677 htlc_minimum_msat: 0,
4678 htlc_maximum_msat: MAX_VALUE_MSAT,
4680 fee_proportional_millionths: 0,
4681 excess_data: Vec::new()
4684 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4685 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4686 short_channel_id: 6,
4689 cltv_expiry_delta: 0,
4690 htlc_minimum_msat: 0,
4691 htlc_maximum_msat: MAX_VALUE_MSAT,
4692 fee_base_msat: 150_000,
4693 fee_proportional_millionths: 0,
4694 excess_data: Vec::new()
4696 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4697 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4698 short_channel_id: 11,
4701 cltv_expiry_delta: 0,
4702 htlc_minimum_msat: 0,
4703 htlc_maximum_msat: MAX_VALUE_MSAT,
4705 fee_proportional_millionths: 0,
4706 excess_data: Vec::new()
4710 // Attempt to route more than available results in a failure.
4711 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4712 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4713 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4714 } else { panic!(); }
4718 // Now, attempt to route 200 sats (exact amount we can route).
4719 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4720 assert_eq!(route.paths.len(), 2);
4722 let mut total_amount_paid_msat = 0;
4723 for path in &route.paths {
4724 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4725 total_amount_paid_msat += path.last().unwrap().fee_msat;
4727 assert_eq!(total_amount_paid_msat, 200_000);
4728 assert_eq!(route.get_total_fees(), 150_000);
4733 fn mpp_with_last_hops() {
4734 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4735 // via a single last-hop route hint, we'd fail to route if we first collected routes
4736 // totaling close but not quite enough to fund the full payment.
4738 // This was because we considered last-hop hints to have exactly the sought payment amount
4739 // instead of the amount we were trying to collect, needlessly limiting our path searching
4740 // at the very first hop.
4742 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4743 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4744 // to only have the remaining to-collect amount in available liquidity.
4746 // This bug appeared in production in some specific channel configurations.
4747 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4748 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4749 let scorer = test_utils::TestScorer::with_penalty(0);
4750 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4751 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4752 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(channelmanager::provided_invoice_features())
4753 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4754 src_node_id: nodes[2],
4755 short_channel_id: 42,
4756 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4757 cltv_expiry_delta: 42,
4758 htlc_minimum_msat: None,
4759 htlc_maximum_msat: None,
4760 }])]).with_max_channel_saturation_power_of_half(0);
4762 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4763 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4764 // would first use the no-fee route and then fail to find a path along the second route as
4765 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4766 // under 5% of our payment amount.
4767 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4768 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4769 short_channel_id: 1,
4772 cltv_expiry_delta: (5 << 4) | 5,
4773 htlc_minimum_msat: 0,
4774 htlc_maximum_msat: 99_000,
4775 fee_base_msat: u32::max_value(),
4776 fee_proportional_millionths: u32::max_value(),
4777 excess_data: Vec::new()
4779 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4780 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4781 short_channel_id: 2,
4784 cltv_expiry_delta: (5 << 4) | 3,
4785 htlc_minimum_msat: 0,
4786 htlc_maximum_msat: 99_000,
4787 fee_base_msat: u32::max_value(),
4788 fee_proportional_millionths: u32::max_value(),
4789 excess_data: Vec::new()
4791 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4792 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4793 short_channel_id: 4,
4796 cltv_expiry_delta: (4 << 4) | 1,
4797 htlc_minimum_msat: 0,
4798 htlc_maximum_msat: MAX_VALUE_MSAT,
4800 fee_proportional_millionths: 0,
4801 excess_data: Vec::new()
4803 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4804 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4805 short_channel_id: 13,
4807 flags: 0|2, // Channel disabled
4808 cltv_expiry_delta: (13 << 4) | 1,
4809 htlc_minimum_msat: 0,
4810 htlc_maximum_msat: MAX_VALUE_MSAT,
4812 fee_proportional_millionths: 2000000,
4813 excess_data: Vec::new()
4816 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4818 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();
4819 assert_eq!(route.paths.len(), 2);
4820 route.paths.sort_by_key(|path| path[0].short_channel_id);
4821 // Paths are manually ordered ordered by SCID, so:
4822 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4823 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4824 assert_eq!(route.paths[0][0].short_channel_id, 1);
4825 assert_eq!(route.paths[0][0].fee_msat, 0);
4826 assert_eq!(route.paths[0][2].fee_msat, 99_000);
4827 assert_eq!(route.paths[1][0].short_channel_id, 2);
4828 assert_eq!(route.paths[1][0].fee_msat, 1);
4829 assert_eq!(route.paths[1][2].fee_msat, 1_000);
4830 assert_eq!(route.get_total_fees(), 1);
4831 assert_eq!(route.get_total_amount(), 100_000);
4835 fn drop_lowest_channel_mpp_route_test() {
4836 // This test checks that low-capacity channel is dropped when after
4837 // path finding we realize that we found more capacity than we need.
4838 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4839 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4840 let scorer = test_utils::TestScorer::with_penalty(0);
4841 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4842 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4843 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features())
4844 .with_max_channel_saturation_power_of_half(0);
4846 // We need a route consisting of 3 paths:
4847 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4849 // The first and the second paths should be sufficient, but the third should be
4850 // cheaper, so that we select it but drop later.
4852 // First, we set limits on these (previously unlimited) channels.
4853 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4855 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4856 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4857 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4858 short_channel_id: 1,
4861 cltv_expiry_delta: 0,
4862 htlc_minimum_msat: 0,
4863 htlc_maximum_msat: 100_000,
4865 fee_proportional_millionths: 0,
4866 excess_data: Vec::new()
4868 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4869 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4870 short_channel_id: 3,
4873 cltv_expiry_delta: 0,
4874 htlc_minimum_msat: 0,
4875 htlc_maximum_msat: 50_000,
4877 fee_proportional_millionths: 0,
4878 excess_data: Vec::new()
4881 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4882 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4883 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4884 short_channel_id: 12,
4887 cltv_expiry_delta: 0,
4888 htlc_minimum_msat: 0,
4889 htlc_maximum_msat: 60_000,
4891 fee_proportional_millionths: 0,
4892 excess_data: Vec::new()
4894 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4895 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4896 short_channel_id: 13,
4899 cltv_expiry_delta: 0,
4900 htlc_minimum_msat: 0,
4901 htlc_maximum_msat: 60_000,
4903 fee_proportional_millionths: 0,
4904 excess_data: Vec::new()
4907 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4908 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4909 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4910 short_channel_id: 2,
4913 cltv_expiry_delta: 0,
4914 htlc_minimum_msat: 0,
4915 htlc_maximum_msat: 20_000,
4917 fee_proportional_millionths: 0,
4918 excess_data: Vec::new()
4920 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4921 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4922 short_channel_id: 4,
4925 cltv_expiry_delta: 0,
4926 htlc_minimum_msat: 0,
4927 htlc_maximum_msat: 20_000,
4929 fee_proportional_millionths: 0,
4930 excess_data: Vec::new()
4934 // Attempt to route more than available results in a failure.
4935 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4936 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4937 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4938 } else { panic!(); }
4942 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4943 // Our algorithm should provide us with these 3 paths.
4944 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4945 assert_eq!(route.paths.len(), 3);
4946 let mut total_amount_paid_msat = 0;
4947 for path in &route.paths {
4948 assert_eq!(path.len(), 2);
4949 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4950 total_amount_paid_msat += path.last().unwrap().fee_msat;
4952 assert_eq!(total_amount_paid_msat, 125_000);
4956 // Attempt to route without the last small cheap channel
4957 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4958 assert_eq!(route.paths.len(), 2);
4959 let mut total_amount_paid_msat = 0;
4960 for path in &route.paths {
4961 assert_eq!(path.len(), 2);
4962 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4963 total_amount_paid_msat += path.last().unwrap().fee_msat;
4965 assert_eq!(total_amount_paid_msat, 90_000);
4970 fn min_criteria_consistency() {
4971 // Test that we don't use an inconsistent metric between updating and walking nodes during
4972 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4973 // was updated with a different criterion from the heap sorting, resulting in loops in
4974 // calculated paths. We test for that specific case here.
4976 // We construct a network that looks like this:
4978 // node2 -1(3)2- node3
4982 // node1 -1(5)2- node4 -1(1)2- node6
4988 // We create a loop on the side of our real path - our destination is node 6, with a
4989 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4990 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4991 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4992 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4993 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4994 // "previous hop" being set to node 3, creating a loop in the path.
4995 let secp_ctx = Secp256k1::new();
4996 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4997 let logger = Arc::new(test_utils::TestLogger::new());
4998 let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
4999 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
5000 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5001 let scorer = test_utils::TestScorer::with_penalty(0);
5002 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5003 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5004 let payment_params = PaymentParameters::from_node_id(nodes[6]);
5006 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
5007 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5008 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5009 short_channel_id: 6,
5012 cltv_expiry_delta: (6 << 4) | 0,
5013 htlc_minimum_msat: 0,
5014 htlc_maximum_msat: MAX_VALUE_MSAT,
5016 fee_proportional_millionths: 0,
5017 excess_data: Vec::new()
5019 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
5021 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
5022 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5023 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5024 short_channel_id: 5,
5027 cltv_expiry_delta: (5 << 4) | 0,
5028 htlc_minimum_msat: 0,
5029 htlc_maximum_msat: MAX_VALUE_MSAT,
5031 fee_proportional_millionths: 0,
5032 excess_data: Vec::new()
5034 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
5036 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
5037 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5038 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5039 short_channel_id: 4,
5042 cltv_expiry_delta: (4 << 4) | 0,
5043 htlc_minimum_msat: 0,
5044 htlc_maximum_msat: MAX_VALUE_MSAT,
5046 fee_proportional_millionths: 0,
5047 excess_data: Vec::new()
5049 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
5051 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
5052 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
5053 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5054 short_channel_id: 3,
5057 cltv_expiry_delta: (3 << 4) | 0,
5058 htlc_minimum_msat: 0,
5059 htlc_maximum_msat: MAX_VALUE_MSAT,
5061 fee_proportional_millionths: 0,
5062 excess_data: Vec::new()
5064 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
5066 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
5067 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
5068 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5069 short_channel_id: 2,
5072 cltv_expiry_delta: (2 << 4) | 0,
5073 htlc_minimum_msat: 0,
5074 htlc_maximum_msat: MAX_VALUE_MSAT,
5076 fee_proportional_millionths: 0,
5077 excess_data: Vec::new()
5080 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
5081 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
5082 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5083 short_channel_id: 1,
5086 cltv_expiry_delta: (1 << 4) | 0,
5087 htlc_minimum_msat: 100,
5088 htlc_maximum_msat: MAX_VALUE_MSAT,
5090 fee_proportional_millionths: 0,
5091 excess_data: Vec::new()
5093 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
5096 // Now ensure the route flows simply over nodes 1 and 4 to 6.
5097 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5098 assert_eq!(route.paths.len(), 1);
5099 assert_eq!(route.paths[0].len(), 3);
5101 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
5102 assert_eq!(route.paths[0][0].short_channel_id, 6);
5103 assert_eq!(route.paths[0][0].fee_msat, 100);
5104 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
5105 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
5106 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
5108 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
5109 assert_eq!(route.paths[0][1].short_channel_id, 5);
5110 assert_eq!(route.paths[0][1].fee_msat, 0);
5111 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
5112 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
5113 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
5115 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
5116 assert_eq!(route.paths[0][2].short_channel_id, 1);
5117 assert_eq!(route.paths[0][2].fee_msat, 10_000);
5118 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
5119 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
5120 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
5126 fn exact_fee_liquidity_limit() {
5127 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
5128 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
5129 // we calculated fees on a higher value, resulting in us ignoring such paths.
5130 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5131 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
5132 let scorer = test_utils::TestScorer::with_penalty(0);
5133 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5134 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5135 let payment_params = PaymentParameters::from_node_id(nodes[2]);
5137 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
5139 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5140 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5141 short_channel_id: 2,
5144 cltv_expiry_delta: 0,
5145 htlc_minimum_msat: 0,
5146 htlc_maximum_msat: 85_000,
5148 fee_proportional_millionths: 0,
5149 excess_data: Vec::new()
5152 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5153 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5154 short_channel_id: 12,
5157 cltv_expiry_delta: (4 << 4) | 1,
5158 htlc_minimum_msat: 0,
5159 htlc_maximum_msat: 270_000,
5161 fee_proportional_millionths: 1000000,
5162 excess_data: Vec::new()
5166 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
5167 // 200% fee charged channel 13 in the 1-to-2 direction.
5168 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5169 assert_eq!(route.paths.len(), 1);
5170 assert_eq!(route.paths[0].len(), 2);
5172 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
5173 assert_eq!(route.paths[0][0].short_channel_id, 12);
5174 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
5175 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
5176 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
5177 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
5179 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
5180 assert_eq!(route.paths[0][1].short_channel_id, 13);
5181 assert_eq!(route.paths[0][1].fee_msat, 90_000);
5182 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
5183 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
5184 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
5189 fn htlc_max_reduction_below_min() {
5190 // Test that if, while walking the graph, we reduce the value being sent to meet an
5191 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
5192 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
5193 // resulting in us thinking there is no possible path, even if other paths exist.
5194 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5195 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5196 let scorer = test_utils::TestScorer::with_penalty(0);
5197 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5198 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5199 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
5201 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5202 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5203 // then try to send 90_000.
5204 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5205 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5206 short_channel_id: 2,
5209 cltv_expiry_delta: 0,
5210 htlc_minimum_msat: 0,
5211 htlc_maximum_msat: 80_000,
5213 fee_proportional_millionths: 0,
5214 excess_data: Vec::new()
5216 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5217 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5218 short_channel_id: 4,
5221 cltv_expiry_delta: (4 << 4) | 1,
5222 htlc_minimum_msat: 90_000,
5223 htlc_maximum_msat: MAX_VALUE_MSAT,
5225 fee_proportional_millionths: 0,
5226 excess_data: Vec::new()
5230 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5231 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5232 // expensive) channels 12-13 path.
5233 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5234 assert_eq!(route.paths.len(), 1);
5235 assert_eq!(route.paths[0].len(), 2);
5237 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
5238 assert_eq!(route.paths[0][0].short_channel_id, 12);
5239 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
5240 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
5241 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
5242 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
5244 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
5245 assert_eq!(route.paths[0][1].short_channel_id, 13);
5246 assert_eq!(route.paths[0][1].fee_msat, 90_000);
5247 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
5248 assert_eq!(route.paths[0][1].node_features.le_flags(), channelmanager::provided_invoice_features().le_flags());
5249 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
5254 fn multiple_direct_first_hops() {
5255 // Previously we'd only ever considered one first hop path per counterparty.
5256 // However, as we don't restrict users to one channel per peer, we really need to support
5257 // looking at all first hop paths.
5258 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5259 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5260 // route over multiple channels with the same first hop.
5261 let secp_ctx = Secp256k1::new();
5262 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5263 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
5264 let logger = Arc::new(test_utils::TestLogger::new());
5265 let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
5266 let scorer = test_utils::TestScorer::with_penalty(0);
5267 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(channelmanager::provided_invoice_features());
5268 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5269 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5272 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5273 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 200_000),
5274 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 10_000),
5275 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5276 assert_eq!(route.paths.len(), 1);
5277 assert_eq!(route.paths[0].len(), 1);
5279 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5280 assert_eq!(route.paths[0][0].short_channel_id, 3);
5281 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5284 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5285 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
5286 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
5287 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5288 assert_eq!(route.paths.len(), 2);
5289 assert_eq!(route.paths[0].len(), 1);
5290 assert_eq!(route.paths[1].len(), 1);
5292 assert!((route.paths[0][0].short_channel_id == 3 && route.paths[1][0].short_channel_id == 2) ||
5293 (route.paths[0][0].short_channel_id == 2 && route.paths[1][0].short_channel_id == 3));
5295 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5296 assert_eq!(route.paths[0][0].fee_msat, 50_000);
5298 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
5299 assert_eq!(route.paths[1][0].fee_msat, 50_000);
5303 // If we have a bunch of outbound channels to the same node, where most are not
5304 // sufficient to pay the full payment, but one is, we should default to just using the
5305 // one single channel that has sufficient balance, avoiding MPP.
5307 // If we have several options above the 3xpayment value threshold, we should pick the
5308 // smallest of them, avoiding further fragmenting our available outbound balance to
5310 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5311 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
5312 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
5313 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(), 50_000),
5314 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(), 300_000),
5315 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(), 50_000),
5316 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(), 50_000),
5317 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(), 50_000),
5318 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(), 1_000_000),
5319 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5320 assert_eq!(route.paths.len(), 1);
5321 assert_eq!(route.paths[0].len(), 1);
5323 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5324 assert_eq!(route.paths[0][0].short_channel_id, 6);
5325 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5330 fn prefers_shorter_route_with_higher_fees() {
5331 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5332 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5333 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5335 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5336 let scorer = test_utils::TestScorer::with_penalty(0);
5337 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5338 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5339 let route = get_route(
5340 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5341 Arc::clone(&logger), &scorer, &random_seed_bytes
5343 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5345 assert_eq!(route.get_total_fees(), 100);
5346 assert_eq!(route.get_total_amount(), 100);
5347 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5349 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5350 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5351 let scorer = test_utils::TestScorer::with_penalty(100);
5352 let route = get_route(
5353 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5354 Arc::clone(&logger), &scorer, &random_seed_bytes
5356 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5358 assert_eq!(route.get_total_fees(), 300);
5359 assert_eq!(route.get_total_amount(), 100);
5360 assert_eq!(path, vec![2, 4, 7, 10]);
5363 struct BadChannelScorer {
5364 short_channel_id: u64,
5368 impl Writeable for BadChannelScorer {
5369 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5371 impl Score for BadChannelScorer {
5372 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage) -> u64 {
5373 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5376 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5377 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5378 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5379 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5382 struct BadNodeScorer {
5387 impl Writeable for BadNodeScorer {
5388 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5391 impl Score for BadNodeScorer {
5392 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage) -> u64 {
5393 if *target == self.node_id { u64::max_value() } else { 0 }
5396 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5397 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5398 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5399 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5403 fn avoids_routing_through_bad_channels_and_nodes() {
5404 let (secp_ctx, network, _, _, logger) = build_graph();
5405 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5406 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5407 let network_graph = network.read_only();
5409 // A path to nodes[6] exists when no penalties are applied to any channel.
5410 let scorer = test_utils::TestScorer::with_penalty(0);
5411 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5412 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5413 let route = get_route(
5414 &our_id, &payment_params, &network_graph, None, 100, 42,
5415 Arc::clone(&logger), &scorer, &random_seed_bytes
5417 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5419 assert_eq!(route.get_total_fees(), 100);
5420 assert_eq!(route.get_total_amount(), 100);
5421 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5423 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5424 let scorer = BadChannelScorer { short_channel_id: 6 };
5425 let route = get_route(
5426 &our_id, &payment_params, &network_graph, None, 100, 42,
5427 Arc::clone(&logger), &scorer, &random_seed_bytes
5429 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5431 assert_eq!(route.get_total_fees(), 300);
5432 assert_eq!(route.get_total_amount(), 100);
5433 assert_eq!(path, vec![2, 4, 7, 10]);
5435 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5436 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5438 &our_id, &payment_params, &network_graph, None, 100, 42,
5439 Arc::clone(&logger), &scorer, &random_seed_bytes
5441 Err(LightningError { err, .. } ) => {
5442 assert_eq!(err, "Failed to find a path to the given destination");
5444 Ok(_) => panic!("Expected error"),
5449 fn total_fees_single_path() {
5453 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5454 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5455 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5458 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5459 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5460 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5463 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5464 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5465 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5468 payment_params: None,
5471 assert_eq!(route.get_total_fees(), 250);
5472 assert_eq!(route.get_total_amount(), 225);
5476 fn total_fees_multi_path() {
5480 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5481 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5482 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5485 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5486 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5487 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5491 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5492 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5493 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5496 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5497 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5498 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5501 payment_params: None,
5504 assert_eq!(route.get_total_fees(), 200);
5505 assert_eq!(route.get_total_amount(), 300);
5509 fn total_empty_route_no_panic() {
5510 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5511 // would both panic if the route was completely empty. We test to ensure they return 0
5512 // here, even though its somewhat nonsensical as a route.
5513 let route = Route { paths: Vec::new(), payment_params: None };
5515 assert_eq!(route.get_total_fees(), 0);
5516 assert_eq!(route.get_total_amount(), 0);
5520 fn limits_total_cltv_delta() {
5521 let (secp_ctx, network, _, _, logger) = build_graph();
5522 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5523 let network_graph = network.read_only();
5525 let scorer = test_utils::TestScorer::with_penalty(0);
5527 // Make sure that generally there is at least one route available
5528 let feasible_max_total_cltv_delta = 1008;
5529 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5530 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5531 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5532 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5533 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5534 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5535 assert_ne!(path.len(), 0);
5537 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5538 let fail_max_total_cltv_delta = 23;
5539 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5540 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5541 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5543 Err(LightningError { err, .. } ) => {
5544 assert_eq!(err, "Failed to find a path to the given destination");
5546 Ok(_) => panic!("Expected error"),
5551 fn avoids_recently_failed_paths() {
5552 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5553 // randomly inserting channels into it until we can't find a route anymore.
5554 let (secp_ctx, network, _, _, logger) = build_graph();
5555 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5556 let network_graph = network.read_only();
5558 let scorer = test_utils::TestScorer::with_penalty(0);
5559 let mut payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5560 .with_max_path_count(1);
5561 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5562 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5564 // We should be able to find a route initially, and then after we fail a few random
5565 // channels eventually we won't be able to any longer.
5566 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).is_ok());
5568 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes) {
5569 for chan in route.paths[0].iter() {
5570 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5572 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5573 % route.paths[0].len();
5574 payment_params.previously_failed_channels.push(route.paths[0][victim].short_channel_id);
5580 fn limits_path_length() {
5581 let (secp_ctx, network, _, _, logger) = build_line_graph();
5582 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5583 let network_graph = network.read_only();
5585 let scorer = test_utils::TestScorer::with_penalty(0);
5586 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5587 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5589 // First check we can actually create a long route on this graph.
5590 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5591 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5592 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5593 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5594 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5596 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5597 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5598 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5599 Arc::clone(&logger), &scorer, &random_seed_bytes)
5601 Err(LightningError { err, .. } ) => {
5602 assert_eq!(err, "Failed to find a path to the given destination");
5604 Ok(_) => panic!("Expected error"),
5609 fn adds_and_limits_cltv_offset() {
5610 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5611 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5613 let scorer = test_utils::TestScorer::with_penalty(0);
5615 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5616 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5617 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5618 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5619 assert_eq!(route.paths.len(), 1);
5621 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5623 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5624 let mut route_default = route.clone();
5625 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5626 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5627 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5628 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5629 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5631 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5632 let mut route_limited = route.clone();
5633 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5634 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5635 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5636 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5637 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5641 fn adds_plausible_cltv_offset() {
5642 let (secp_ctx, network, _, _, logger) = build_graph();
5643 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5644 let network_graph = network.read_only();
5645 let network_nodes = network_graph.nodes();
5646 let network_channels = network_graph.channels();
5647 let scorer = test_utils::TestScorer::with_penalty(0);
5648 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5649 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5650 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5652 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5653 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5654 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5656 let mut path_plausibility = vec![];
5658 for p in route.paths {
5659 // 1. Select random observation point
5660 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5661 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5663 prng.process_in_place(&mut random_bytes);
5664 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5665 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5667 // 2. Calculate what CLTV expiry delta we would observe there
5668 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5670 // 3. Starting from the observation point, find candidate paths
5671 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5672 candidates.push_back((observation_point, vec![]));
5674 let mut found_plausible_candidate = false;
5676 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5677 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5678 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5679 found_plausible_candidate = true;
5680 break 'candidate_loop;
5684 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5685 for channel_id in &cur_node.channels {
5686 if let Some(channel_info) = network_channels.get(&channel_id) {
5687 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5688 if let Some(channel_update_info) = dir_info.direction() {
5689 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5690 if cur_path_cltv_deltas.iter().sum::<u32>()
5691 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5692 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5693 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5694 candidates.push_back((*next_id, new_path_cltv_deltas));
5703 path_plausibility.push(found_plausible_candidate);
5705 assert!(path_plausibility.iter().all(|x| *x));
5709 fn builds_correct_path_from_hops() {
5710 let (secp_ctx, network, _, _, logger) = build_graph();
5711 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5712 let network_graph = network.read_only();
5714 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5715 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5717 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5718 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5719 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5720 &network_graph, 100, 0, Arc::clone(&logger), &random_seed_bytes).unwrap();
5721 let route_hop_pubkeys = route.paths[0].iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5722 assert_eq!(hops.len(), route.paths[0].len());
5723 for (idx, hop_pubkey) in hops.iter().enumerate() {
5724 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5729 fn avoids_saturating_channels() {
5730 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5731 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5733 let scorer = ProbabilisticScorer::new(Default::default(), &*network_graph, Arc::clone(&logger));
5735 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5736 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5737 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5738 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5739 short_channel_id: 4,
5742 cltv_expiry_delta: (4 << 4) | 1,
5743 htlc_minimum_msat: 0,
5744 htlc_maximum_msat: 250_000_000,
5746 fee_proportional_millionths: 0,
5747 excess_data: Vec::new()
5749 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5750 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5751 short_channel_id: 13,
5754 cltv_expiry_delta: (13 << 4) | 1,
5755 htlc_minimum_msat: 0,
5756 htlc_maximum_msat: 250_000_000,
5758 fee_proportional_millionths: 0,
5759 excess_data: Vec::new()
5762 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
5763 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5764 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5765 // 100,000 sats is less than the available liquidity on each channel, set above.
5766 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5767 assert_eq!(route.paths.len(), 2);
5768 assert!((route.paths[0][1].short_channel_id == 4 && route.paths[1][1].short_channel_id == 13) ||
5769 (route.paths[1][1].short_channel_id == 4 && route.paths[0][1].short_channel_id == 13));
5772 #[cfg(not(feature = "no-std"))]
5773 pub(super) fn random_init_seed() -> u64 {
5774 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5775 use core::hash::{BuildHasher, Hasher};
5776 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5777 println!("Using seed of {}", seed);
5780 #[cfg(not(feature = "no-std"))]
5781 use util::ser::ReadableArgs;
5784 #[cfg(not(feature = "no-std"))]
5785 fn generate_routes() {
5786 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5788 let mut d = match super::test_utils::get_route_file() {
5795 let logger = test_utils::TestLogger::new();
5796 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5797 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5798 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5800 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5801 let mut seed = random_init_seed() as usize;
5802 let nodes = graph.read_only().nodes().clone();
5803 'load_endpoints: for _ in 0..10 {
5805 seed = seed.overflowing_mul(0xdeadbeef).0;
5806 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5807 seed = seed.overflowing_mul(0xdeadbeef).0;
5808 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5809 let payment_params = PaymentParameters::from_node_id(dst);
5810 let amt = seed as u64 % 200_000_000;
5811 let params = ProbabilisticScoringParameters::default();
5812 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5813 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5814 continue 'load_endpoints;
5821 #[cfg(not(feature = "no-std"))]
5822 fn generate_routes_mpp() {
5823 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5825 let mut d = match super::test_utils::get_route_file() {
5832 let logger = test_utils::TestLogger::new();
5833 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5834 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5835 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5837 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5838 let mut seed = random_init_seed() as usize;
5839 let nodes = graph.read_only().nodes().clone();
5840 'load_endpoints: for _ in 0..10 {
5842 seed = seed.overflowing_mul(0xdeadbeef).0;
5843 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5844 seed = seed.overflowing_mul(0xdeadbeef).0;
5845 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5846 let payment_params = PaymentParameters::from_node_id(dst).with_features(channelmanager::provided_invoice_features());
5847 let amt = seed as u64 % 200_000_000;
5848 let params = ProbabilisticScoringParameters::default();
5849 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5850 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5851 continue 'load_endpoints;
5858 fn honors_manual_penalties() {
5859 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5860 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5862 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5863 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5865 let scorer_params = ProbabilisticScoringParameters::default();
5866 let mut scorer = ProbabilisticScorer::new(scorer_params, Arc::clone(&network_graph), Arc::clone(&logger));
5868 // First check set manual penalties are returned by the scorer.
5869 let usage = ChannelUsage {
5871 inflight_htlc_msat: 0,
5872 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: Some(1_000) },
5874 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5875 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5876 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage), 456);
5878 // Then check we can get a normal route
5879 let payment_params = PaymentParameters::from_node_id(nodes[10]);
5880 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5881 assert!(route.is_ok());
5883 // Then check that we can't get a route if we ban an intermediate node.
5884 scorer.add_banned(&NodeId::from_pubkey(&nodes[3]));
5885 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5886 assert!(route.is_err());
5888 // Finally make sure we can route again, when we remove the ban.
5889 scorer.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5890 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5891 assert!(route.is_ok());
5895 #[cfg(all(test, not(feature = "no-std")))]
5896 pub(crate) mod test_utils {
5898 /// Tries to open a network graph file, or panics with a URL to fetch it.
5899 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5900 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5901 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5902 .or_else(|_| { // Fall back to guessing based on the binary location
5903 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5904 let mut path = std::env::current_exe().unwrap();
5905 path.pop(); // lightning-...
5907 path.pop(); // debug
5908 path.pop(); // target
5909 path.push("lightning");
5910 path.push("net_graph-2021-05-31.bin");
5911 eprintln!("{}", path.to_str().unwrap());
5914 .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");
5915 #[cfg(require_route_graph_test)]
5916 return Ok(res.unwrap());
5917 #[cfg(not(require_route_graph_test))]
5922 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5925 use bitcoin::hashes::Hash;
5926 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5927 use chain::transaction::OutPoint;
5928 use chain::keysinterface::{KeysManager,KeysInterface};
5929 use ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
5930 use ln::features::{InitFeatures, InvoiceFeatures};
5931 use routing::gossip::NetworkGraph;
5932 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
5933 use util::logger::{Logger, Record};
5934 use util::ser::ReadableArgs;
5938 struct DummyLogger {}
5939 impl Logger for DummyLogger {
5940 fn log(&self, _record: &Record) {}
5943 fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
5944 let mut d = test_utils::get_route_file().unwrap();
5945 NetworkGraph::read(&mut d, logger).unwrap()
5948 fn payer_pubkey() -> PublicKey {
5949 let secp_ctx = Secp256k1::new();
5950 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5954 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5956 channel_id: [0; 32],
5957 counterparty: ChannelCounterparty {
5958 features: channelmanager::provided_init_features(),
5960 unspendable_punishment_reserve: 0,
5961 forwarding_info: None,
5962 outbound_htlc_minimum_msat: None,
5963 outbound_htlc_maximum_msat: None,
5965 funding_txo: Some(OutPoint {
5966 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5969 short_channel_id: Some(1),
5970 inbound_scid_alias: None,
5971 outbound_scid_alias: None,
5972 channel_value_satoshis: 10_000_000,
5974 balance_msat: 10_000_000,
5975 outbound_capacity_msat: 10_000_000,
5976 next_outbound_htlc_limit_msat: 10_000_000,
5977 inbound_capacity_msat: 0,
5978 unspendable_punishment_reserve: None,
5979 confirmations_required: None,
5980 force_close_spend_delay: None,
5982 is_channel_ready: true,
5985 inbound_htlc_minimum_msat: None,
5986 inbound_htlc_maximum_msat: None,
5992 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5993 let logger = DummyLogger {};
5994 let network_graph = read_network_graph(&logger);
5995 let scorer = FixedPenaltyScorer::with_penalty(0);
5996 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
6000 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
6001 let logger = DummyLogger {};
6002 let network_graph = read_network_graph(&logger);
6003 let scorer = FixedPenaltyScorer::with_penalty(0);
6004 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
6008 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
6009 let logger = DummyLogger {};
6010 let network_graph = read_network_graph(&logger);
6011 let params = ProbabilisticScoringParameters::default();
6012 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
6013 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
6017 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
6018 let logger = DummyLogger {};
6019 let network_graph = read_network_graph(&logger);
6020 let params = ProbabilisticScoringParameters::default();
6021 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
6022 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
6025 fn generate_routes<S: Score>(
6026 bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
6027 features: InvoiceFeatures
6029 let nodes = graph.read_only().nodes().clone();
6030 let payer = payer_pubkey();
6031 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
6032 let random_seed_bytes = keys_manager.get_secure_random_bytes();
6034 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
6035 let mut routes = Vec::new();
6036 let mut route_endpoints = Vec::new();
6037 let mut seed: usize = 0xdeadbeef;
6038 'load_endpoints: for _ in 0..150 {
6041 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
6043 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
6044 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
6045 let first_hop = first_hop(src);
6046 let amt = seed as u64 % 1_000_000;
6047 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
6049 route_endpoints.push((first_hop, params, amt));
6050 continue 'load_endpoints;
6055 // ...and seed the scorer with success and failure data...
6056 for route in routes {
6057 let amount = route.get_total_amount();
6058 if amount < 250_000 {
6059 for path in route.paths {
6060 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
6062 } else if amount > 750_000 {
6063 for path in route.paths {
6064 let short_channel_id = path[path.len() / 2].short_channel_id;
6065 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
6070 // Because we've changed channel scores, its possible we'll take different routes to the
6071 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
6072 // requires a too-high CLTV delta.
6073 route_endpoints.retain(|(first_hop, params, amt)| {
6074 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
6076 route_endpoints.truncate(100);
6077 assert_eq!(route_endpoints.len(), 100);
6079 // ...then benchmark finding paths between the nodes we learned.
6082 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
6083 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());