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 NetGraphMsgHandler and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
15 use bitcoin::secp256k1::key::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::scoring::Score;
21 use routing::network_graph::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
22 use util::ser::{Writeable, Readable};
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.
69 /// Each entry represents a list of hops, NOT INCLUDING our own, where the last hop is the
70 /// destination. Thus, this must always be at least length one. While the maximum length of any
71 /// given path is variable, keeping the length of any path to less than 20 should currently
72 /// ensure it is viable.
73 pub paths: Vec<Vec<RouteHop>>,
74 /// The `payment_params` parameter passed to [`find_route`].
75 /// This is used by `ChannelManager` to track information which may be required for retries,
76 /// provided back to you via [`Event::PaymentPathFailed`].
78 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
79 pub payment_params: Option<PaymentParameters>,
82 pub(crate) trait RoutePath {
83 /// Gets the fees for a given path, excluding any excess paid to the recipient.
84 fn get_path_fees(&self) -> u64;
86 impl RoutePath for Vec<RouteHop> {
87 fn get_path_fees(&self) -> u64 {
88 // Do not count last hop of each path since that's the full value of the payment
89 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
90 .iter().map(|hop| &hop.fee_msat)
96 /// Returns the total amount of fees paid on this [`Route`].
98 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
99 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
100 pub fn get_total_fees(&self) -> u64 {
101 self.paths.iter().map(|path| path.get_path_fees()).sum()
104 /// Returns the total amount paid on this [`Route`], excluding the fees.
105 pub fn get_total_amount(&self) -> u64 {
106 return self.paths.iter()
107 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
112 const SERIALIZATION_VERSION: u8 = 1;
113 const MIN_SERIALIZATION_VERSION: u8 = 1;
115 impl Writeable for Route {
116 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
117 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
118 (self.paths.len() as u64).write(writer)?;
119 for hops in self.paths.iter() {
120 (hops.len() as u8).write(writer)?;
121 for hop in hops.iter() {
125 write_tlv_fields!(writer, {
126 (1, self.payment_params, option),
132 impl Readable for Route {
133 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
134 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
135 let path_count: u64 = Readable::read(reader)?;
136 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
137 for _ in 0..path_count {
138 let hop_count: u8 = Readable::read(reader)?;
139 let mut hops = Vec::with_capacity(hop_count as usize);
140 for _ in 0..hop_count {
141 hops.push(Readable::read(reader)?);
145 let mut payment_params = None;
146 read_tlv_fields!(reader, {
147 (1, payment_params, option),
149 Ok(Route { paths, payment_params })
153 /// Parameters needed to find a [`Route`].
155 /// Passed to [`find_route`] and also provided in [`Event::PaymentPathFailed`] for retrying a failed
158 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
159 #[derive(Clone, Debug)]
160 pub struct RouteParameters {
161 /// The parameters of the failed payment path.
162 pub payment_params: PaymentParameters,
164 /// The amount in msats sent on the failed payment path.
165 pub final_value_msat: u64,
167 /// The CLTV on the final hop of the failed payment path.
168 pub final_cltv_expiry_delta: u32,
171 impl_writeable_tlv_based!(RouteParameters, {
172 (0, payment_params, required),
173 (2, final_value_msat, required),
174 (4, final_cltv_expiry_delta, required),
177 /// Maximum total CTLV difference we allow for a full payment path.
178 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
180 /// The median hop CLTV expiry delta currently seen in the network.
181 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
183 /// The recipient of a payment.
184 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
185 pub struct PaymentParameters {
186 /// The node id of the payee.
187 pub payee_pubkey: PublicKey,
189 /// Features supported by the payee.
191 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
192 /// does not contain any features.
194 /// [`for_keysend`]: Self::for_keysend
195 pub features: Option<InvoiceFeatures>,
197 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
198 pub route_hints: Vec<RouteHint>,
200 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
201 pub expiry_time: Option<u64>,
203 /// The maximum total CLTV delta we accept for the route.
204 pub max_total_cltv_expiry_delta: u32,
207 impl_writeable_tlv_based!(PaymentParameters, {
208 (0, payee_pubkey, required),
209 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
210 (2, features, option),
211 (4, route_hints, vec_type),
212 (6, expiry_time, option),
215 impl PaymentParameters {
216 /// Creates a payee with the node id of the given `pubkey`.
217 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
223 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
227 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
228 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
229 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
232 /// Includes the payee's features.
234 /// (C-not exported) since bindings don't support move semantics
235 pub fn with_features(self, features: InvoiceFeatures) -> Self {
236 Self { features: Some(features), ..self }
239 /// Includes hints for routing to the payee.
241 /// (C-not exported) since bindings don't support move semantics
242 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
243 Self { route_hints, ..self }
246 /// Includes a payment expiration in seconds relative to the UNIX epoch.
248 /// (C-not exported) since bindings don't support move semantics
249 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
250 Self { expiry_time: Some(expiry_time), ..self }
253 /// Includes a limit for the total CLTV expiry delta which is considered during routing
255 /// (C-not exported) since bindings don't support move semantics
256 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
257 Self { max_total_cltv_expiry_delta, ..self }
261 /// A list of hops along a payment path terminating with a channel to the recipient.
262 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
263 pub struct RouteHint(pub Vec<RouteHintHop>);
265 impl Writeable for RouteHint {
266 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
267 (self.0.len() as u64).write(writer)?;
268 for hop in self.0.iter() {
275 impl Readable for RouteHint {
276 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
277 let hop_count: u64 = Readable::read(reader)?;
278 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
279 for _ in 0..hop_count {
280 hops.push(Readable::read(reader)?);
286 /// A channel descriptor for a hop along a payment path.
287 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
288 pub struct RouteHintHop {
289 /// The node_id of the non-target end of the route
290 pub src_node_id: PublicKey,
291 /// The short_channel_id of this channel
292 pub short_channel_id: u64,
293 /// The fees which must be paid to use this channel
294 pub fees: RoutingFees,
295 /// The difference in CLTV values between this node and the next node.
296 pub cltv_expiry_delta: u16,
297 /// The minimum value, in msat, which must be relayed to the next hop.
298 pub htlc_minimum_msat: Option<u64>,
299 /// The maximum value in msat available for routing with a single HTLC.
300 pub htlc_maximum_msat: Option<u64>,
303 impl_writeable_tlv_based!(RouteHintHop, {
304 (0, src_node_id, required),
305 (1, htlc_minimum_msat, option),
306 (2, short_channel_id, required),
307 (3, htlc_maximum_msat, option),
309 (6, cltv_expiry_delta, required),
312 #[derive(Eq, PartialEq)]
313 struct RouteGraphNode {
315 lowest_fee_to_peer_through_node: u64,
316 lowest_fee_to_node: u64,
317 total_cltv_delta: u32,
318 // The maximum value a yet-to-be-constructed payment path might flow through this node.
319 // This value is upper-bounded by us by:
320 // - how much is needed for a path being constructed
321 // - how much value can channels following this node (up to the destination) can contribute,
322 // considering their capacity and fees
323 value_contribution_msat: u64,
324 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
325 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
326 path_htlc_minimum_msat: u64,
327 /// All penalties incurred from this hop on the way to the destination, as calculated using
329 path_penalty_msat: u64,
332 impl cmp::Ord for RouteGraphNode {
333 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
334 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
335 .saturating_add(other.path_penalty_msat);
336 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
337 .saturating_add(self.path_penalty_msat);
338 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
342 impl cmp::PartialOrd for RouteGraphNode {
343 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
344 Some(self.cmp(other))
348 /// A wrapper around the various hop representations.
350 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
351 #[derive(Clone, Debug)]
352 enum CandidateRouteHop<'a> {
353 /// A hop from the payer, where the outbound liquidity is known.
355 details: &'a ChannelDetails,
357 /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
359 info: DirectedChannelInfoWithUpdate<'a>,
360 short_channel_id: u64,
362 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
364 hint: &'a RouteHintHop,
368 impl<'a> CandidateRouteHop<'a> {
369 fn short_channel_id(&self) -> u64 {
371 CandidateRouteHop::FirstHop { details } => details.short_channel_id.unwrap(),
372 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
373 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
377 // NOTE: This may alloc memory so avoid calling it in a hot code path.
378 fn features(&self) -> ChannelFeatures {
380 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
381 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
382 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
386 fn cltv_expiry_delta(&self) -> u32 {
388 CandidateRouteHop::FirstHop { .. } => 0,
389 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
390 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
394 fn htlc_minimum_msat(&self) -> u64 {
396 CandidateRouteHop::FirstHop { .. } => 0,
397 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
398 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
402 fn fees(&self) -> RoutingFees {
404 CandidateRouteHop::FirstHop { .. } => RoutingFees {
405 base_msat: 0, proportional_millionths: 0,
407 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
408 CandidateRouteHop::PrivateHop { hint } => hint.fees,
412 fn effective_capacity(&self) -> EffectiveCapacity {
414 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
415 liquidity_msat: details.outbound_capacity_msat,
417 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
418 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
423 /// It's useful to keep track of the hops associated with the fees required to use them,
424 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
425 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
426 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
428 struct PathBuildingHop<'a> {
429 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
430 // is a larger refactor and will require careful performance analysis.
432 candidate: CandidateRouteHop<'a>,
435 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
436 src_lowest_inbound_fees: RoutingFees,
437 /// All the fees paid *after* this channel on the way to the destination
438 next_hops_fee_msat: u64,
439 /// Fee paid for the use of the current channel (see candidate.fees()).
440 /// The value will be actually deducted from the counterparty balance on the previous link.
441 hop_use_fee_msat: u64,
442 /// Used to compare channels when choosing the for routing.
443 /// Includes paying for the use of a hop and the following hops, as well as
444 /// an estimated cost of reaching this hop.
445 /// Might get stale when fees are recomputed. Primarily for internal use.
447 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
448 /// walk and may be invalid thereafter.
449 path_htlc_minimum_msat: u64,
450 /// All penalties incurred from this channel on the way to the destination, as calculated using
452 path_penalty_msat: u64,
453 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
454 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
455 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
456 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
457 /// avoid processing them again.
459 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
460 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
461 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
462 // value_contribution_msat, which requires tracking it here. See comments below where it is
463 // used for more info.
464 value_contribution_msat: u64,
467 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
468 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
469 f.debug_struct("PathBuildingHop")
470 .field("node_id", &self.node_id)
471 .field("short_channel_id", &self.candidate.short_channel_id())
472 .field("total_fee_msat", &self.total_fee_msat)
473 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
474 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
475 .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)))
476 .field("path_penalty_msat", &self.path_penalty_msat)
477 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
478 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta())
483 // Instantiated with a list of hops with correct data in them collected during path finding,
484 // an instance of this struct should be further modified only via given methods.
486 struct PaymentPath<'a> {
487 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
490 impl<'a> PaymentPath<'a> {
491 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
492 fn get_value_msat(&self) -> u64 {
493 self.hops.last().unwrap().0.fee_msat
496 fn get_path_penalty_msat(&self) -> u64 {
497 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
500 fn get_total_fee_paid_msat(&self) -> u64 {
501 if self.hops.len() < 1 {
505 // Can't use next_hops_fee_msat because it gets outdated.
506 for (i, (hop, _)) in self.hops.iter().enumerate() {
507 if i != self.hops.len() - 1 {
508 result += hop.fee_msat;
514 fn get_cost_msat(&self) -> u64 {
515 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
518 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
519 // to change fees may result in an inconsistency.
521 // Sometimes we call this function right after constructing a path which is inconsistent in
522 // that it the value being transferred has decreased while we were doing path finding, leading
523 // to the fees being paid not lining up with the actual limits.
525 // Note that this function is not aware of the available_liquidity limit, and thus does not
526 // support increasing the value being transferred.
527 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
528 assert!(value_msat <= self.hops.last().unwrap().0.fee_msat);
530 let mut total_fee_paid_msat = 0 as u64;
531 for i in (0..self.hops.len()).rev() {
532 let last_hop = i == self.hops.len() - 1;
534 // For non-last-hop, this value will represent the fees paid on the current hop. It
535 // will consist of the fees for the use of the next hop, and extra fees to match
536 // htlc_minimum_msat of the current channel. Last hop is handled separately.
537 let mut cur_hop_fees_msat = 0;
539 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
542 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
543 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
544 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
545 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
546 // set it too high just to maliciously take more fees by exploiting this
547 // match htlc_minimum_msat logic.
548 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
549 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
550 // Note that there is a risk that *previous hops* (those closer to us, as we go
551 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
553 // This might make us end up with a broken route, although this should be super-rare
554 // in practice, both because of how healthy channels look like, and how we pick
555 // channels in add_entry.
556 // Also, this can't be exploited more heavily than *announce a free path and fail
558 cur_hop_transferred_amount_msat += extra_fees_msat;
559 total_fee_paid_msat += extra_fees_msat;
560 cur_hop_fees_msat += extra_fees_msat;
564 // Final hop is a special case: it usually has just value_msat (by design), but also
565 // it still could overpay for the htlc_minimum_msat.
566 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
568 // Propagate updated fees for the use of the channels to one hop back, where they
569 // will be actually paid (fee_msat). The last hop is handled above separately.
570 cur_hop.fee_msat = cur_hop_fees_msat;
573 // Fee for the use of the current hop which will be deducted on the previous hop.
574 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
575 // this channel is free for us.
577 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
578 cur_hop.hop_use_fee_msat = new_fee;
579 total_fee_paid_msat += new_fee;
581 // It should not be possible because this function is called only to reduce the
582 // value. In that case, compute_fee was already called with the same fees for
583 // larger amount and there was no overflow.
591 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
592 let proportional_fee_millions =
593 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
594 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
595 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
599 // This function may be (indirectly) called without any verification,
600 // with channel_fees provided by a caller. We should handle it gracefully.
605 /// Finds a route from us (payer) to the given target node (payee).
607 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
608 /// Without this, MPP will only be used if the payee's features are available in the network graph.
610 /// Private routing paths between a public node and the target may be included in `params.payee`.
612 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
613 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
614 /// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
616 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
617 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
618 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
622 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
623 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
628 /// Panics if first_hops contains channels without short_channel_ids;
629 /// [`ChannelManager::list_usable_channels`] will never include such channels.
631 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
632 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
633 pub fn find_route<L: Deref, S: Score>(
634 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network: &NetworkGraph,
635 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
636 ) -> Result<Route, LightningError>
637 where L::Target: Logger {
638 let network_graph = network.read_only();
640 our_node_pubkey, &route_params.payment_params, &network_graph, first_hops, route_params.final_value_msat,
641 route_params.final_cltv_expiry_delta, logger, scorer, random_seed_bytes
644 add_random_cltv_offset(&mut route, &route_params.payment_params, &network_graph, random_seed_bytes);
647 Err(err) => Err(err),
651 pub(crate) fn get_route<L: Deref, S: Score>(
652 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
653 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
654 logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
655 ) -> Result<Route, LightningError>
656 where L::Target: Logger {
657 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
658 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
660 if payee_node_id == our_node_id {
661 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
664 if final_value_msat > MAX_VALUE_MSAT {
665 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
668 if final_value_msat == 0 {
669 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
672 for route in payment_params.route_hints.iter() {
673 for hop in &route.0 {
674 if hop.src_node_id == payment_params.payee_pubkey {
675 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
679 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
680 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});
683 // The general routing idea is the following:
684 // 1. Fill first/last hops communicated by the caller.
685 // 2. Attempt to construct a path from payer to payee for transferring
686 // any ~sufficient (described later) value.
687 // If succeed, remember which channels were used and how much liquidity they have available,
688 // so that future paths don't rely on the same liquidity.
689 // 3. Proceed to the next step if:
690 // - we hit the recommended target value;
691 // - OR if we could not construct a new path. Any next attempt will fail too.
692 // Otherwise, repeat step 2.
693 // 4. See if we managed to collect paths which aggregately are able to transfer target value
694 // (not recommended value).
695 // 5. If yes, proceed. If not, fail routing.
696 // 6. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
697 // 7. Of all the found paths, select only those with the lowest total fee.
698 // 8. The last path in every selected route is likely to be more than we need.
699 // Reduce its value-to-transfer and recompute fees.
700 // 9. Choose the best route by the lowest total fee.
702 // As for the actual search algorithm,
703 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
704 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
706 // We are not a faithful Dijkstra's implementation because we can change values which impact
707 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
708 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
709 // the value we are currently attempting to send over a path, we simply reduce the value being
710 // sent along the path for any hops after that channel. This may imply that later fees (which
711 // we've already tabulated) are lower because a smaller value is passing through the channels
712 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
713 // channels which were selected earlier (and which may still be used for other paths without a
714 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
717 // One potentially problematic case for this algorithm would be if there are many
718 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
719 // graph walking), we may never find a path which is not liquidity-limited and has lower
720 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
721 // Because we only consider paths with at least 5% of the total value being sent, the damage
722 // from such a case should be limited, however this could be further reduced in the future by
723 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
724 // limits for the purposes of fee calculation.
726 // Alternatively, we could store more detailed path information in the heap (targets, below)
727 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
728 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
729 // and practically (as we would need to store dynamically-allocated path information in heap
730 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
731 // results of such an algorithm would likely be biased towards lower-value paths.
733 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
734 // outside of our current search value, running a path search more times to gather candidate
735 // paths at different values. While this may be acceptable, further path searches may increase
736 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
737 // graph for candidate paths, calculating the maximum value which can realistically be sent at
738 // the same time, remaining generic across different payment values.
740 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
741 // to use as the A* heuristic beyond just the cost to get one node further than the current
744 let network_channels = network_graph.channels();
745 let network_nodes = network_graph.nodes();
747 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
748 // it. If the payee supports it they're supposed to include it in the invoice, so that should
750 let allow_mpp = if let Some(features) = &payment_params.features {
751 features.supports_basic_mpp()
752 } else if let Some(node) = network_nodes.get(&payee_node_id) {
753 if let Some(node_info) = node.announcement_info.as_ref() {
754 node_info.features.supports_basic_mpp()
757 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
758 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
759 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
762 // Prepare the data we'll use for payee-to-payer search by
763 // inserting first hops suggested by the caller as targets.
764 // Our search will then attempt to reach them while traversing from the payee node.
765 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
766 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
767 if let Some(hops) = first_hops {
769 if chan.short_channel_id.is_none() {
770 panic!("first_hops should be filled in with usable channels, not pending ones");
772 if chan.counterparty.node_id == *our_node_pubkey {
773 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
776 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
777 .or_insert(Vec::new())
780 if first_hop_targets.is_empty() {
781 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
785 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
786 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
787 // adding duplicate entries when we find a better path to a given node.
788 let mut targets = BinaryHeap::new();
790 // Map from node_id to information about the best current path to that node, including feerate
792 let mut dist = HashMap::with_capacity(network_nodes.len());
794 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
795 // indicating that we may wish to try again with a higher value, potentially paying to meet an
796 // htlc_minimum with extra fees while still finding a cheaper path.
797 let mut hit_minimum_limit;
799 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
800 // We start with a path_value of the exact amount we want, and if that generates a route we may
801 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
802 // amount we want in total across paths, selecting the best subset at the end.
803 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
804 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
805 let mut path_value_msat = final_value_msat;
807 // We don't want multiple paths (as per MPP) share liquidity of the same channels.
808 // This map allows paths to be aware of the channel use by other paths in the same call.
809 // This would help to make a better path finding decisions and not "overbook" channels.
810 // It is unaware of the directions (except for `outbound_capacity_msat` in `first_hops`).
811 let mut bookkept_channels_liquidity_available_msat = HashMap::with_capacity(network_nodes.len());
813 // Keeping track of how much value we already collected across other paths. Helps to decide:
814 // - how much a new path should be transferring (upper bound);
815 // - whether a channel should be disregarded because
816 // it's available liquidity is too small comparing to how much more we need to collect;
817 // - when we want to stop looking for new paths.
818 let mut already_collected_value_msat = 0;
820 for (_, channels) in first_hop_targets.iter_mut() {
821 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
824 // First, if channels are below `recommended_value_msat`, sort them in descending order,
825 // preferring larger channels to avoid splitting the payment into more MPP parts than is
828 // Second, because simply always sorting in descending order would always use our largest
829 // available outbound capacity, needlessly fragmenting our available channel capacities,
830 // sort channels above `recommended_value_msat` in ascending order, preferring channels
831 // which have enough, but not too much, capacity for the payment.
832 channels.sort_unstable_by(|chan_a, chan_b| {
833 if chan_b.outbound_capacity_msat < recommended_value_msat || chan_a.outbound_capacity_msat < recommended_value_msat {
834 // Sort in descending order
835 chan_b.outbound_capacity_msat.cmp(&chan_a.outbound_capacity_msat)
837 // Sort in ascending order
838 chan_a.outbound_capacity_msat.cmp(&chan_b.outbound_capacity_msat)
843 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
845 macro_rules! add_entry {
846 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
847 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
848 // since that value has to be transferred over this channel.
849 // Returns whether this channel caused an update to `targets`.
850 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
851 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
852 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => { {
853 // We "return" whether we updated the path at the end, via this:
854 let mut did_add_update_path_to_src_node = false;
855 // Channels to self should not be used. This is more of belt-and-suspenders, because in
856 // practice these cases should be caught earlier:
857 // - for regular channels at channel announcement (TODO)
858 // - for first and last hops early in get_route
859 if $src_node_id != $dest_node_id {
860 let short_channel_id = $candidate.short_channel_id();
861 let available_liquidity_msat = bookkept_channels_liquidity_available_msat
862 .entry(short_channel_id)
863 .or_insert_with(|| $candidate.effective_capacity().as_msat());
865 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
866 // It may be misleading because we might later choose to reduce the value transferred
867 // over these channels, and the channel which was insufficient might become sufficient.
868 // Worst case: we drop a good channel here because it can't cover the high following
869 // fees caused by one expensive channel, but then this channel could have been used
870 // if the amount being transferred over this path is lower.
871 // We do this for now, but this is a subject for removal.
872 if let Some(available_value_contribution_msat) = available_liquidity_msat.checked_sub($next_hops_fee_msat) {
874 // Routing Fragmentation Mitigation heuristic:
876 // Routing fragmentation across many payment paths increases the overall routing
877 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
878 // Taking too many smaller paths also increases the chance of payment failure.
879 // Thus to avoid this effect, we require from our collected links to provide
880 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
882 // This requirement is currently 5% of the remaining-to-be-collected value.
883 // This means as we successfully advance in our collection,
884 // the absolute liquidity contribution is lowered,
885 // thus increasing the number of potential channels to be selected.
887 // Derive the minimal liquidity contribution with a ratio of 20 (5%, rounded up)
888 // or 100% if we're not allowed to do multipath payments.
889 let minimal_value_contribution_msat: u64 = if allow_mpp {
890 (recommended_value_msat - already_collected_value_msat + 19) / 20
894 // Verify the liquidity offered by this channel complies to the minimal contribution.
895 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
897 // Do not consider candidates that exceed the maximum total cltv expiry limit.
898 // In order to already account for some of the privacy enhancing random CLTV
899 // expiry delta offset we add on top later, we subtract a rough estimate
900 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
901 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
902 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
903 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
904 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
905 .saturating_add($candidate.cltv_expiry_delta());
906 let doesnt_exceed_cltv_delta_limit = hop_total_cltv_delta <= max_total_cltv_expiry_delta;
908 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
909 // Includes paying fees for the use of the following channels.
910 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
911 Some(result) => result,
912 // Can't overflow due to how the values were computed right above.
913 None => unreachable!(),
915 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
916 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
917 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
919 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
920 let may_overpay_to_meet_path_minimum_msat =
921 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
922 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
923 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
924 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
926 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
927 // bother considering this channel. If retrying with recommended_value_msat may
928 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
929 // around again with a higher amount.
930 if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit && may_overpay_to_meet_path_minimum_msat {
931 hit_minimum_limit = true;
932 } else if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit && over_path_minimum_msat {
933 // Note that low contribution here (limited by available_liquidity_msat)
934 // might violate htlc_minimum_msat on the hops which are next along the
935 // payment path (upstream to the payee). To avoid that, we recompute
936 // path fees knowing the final path contribution after constructing it.
937 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
938 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
939 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
940 .unwrap_or_else(|| u64::max_value());
941 let hm_entry = dist.entry($src_node_id);
942 let old_entry = hm_entry.or_insert_with(|| {
943 // If there was previously no known way to access the source node
944 // (recall it goes payee-to-payer) of short_channel_id, first add a
945 // semi-dummy record just to compute the fees to reach the source node.
946 // This will affect our decision on selecting short_channel_id
947 // as a way to reach the $dest_node_id.
948 let mut fee_base_msat = 0;
949 let mut fee_proportional_millionths = 0;
950 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
951 fee_base_msat = fees.base_msat;
952 fee_proportional_millionths = fees.proportional_millionths;
955 node_id: $dest_node_id.clone(),
956 candidate: $candidate.clone(),
958 src_lowest_inbound_fees: RoutingFees {
959 base_msat: fee_base_msat,
960 proportional_millionths: fee_proportional_millionths,
962 next_hops_fee_msat: u64::max_value(),
963 hop_use_fee_msat: u64::max_value(),
964 total_fee_msat: u64::max_value(),
965 path_htlc_minimum_msat,
966 path_penalty_msat: u64::max_value(),
967 was_processed: false,
968 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
969 value_contribution_msat,
973 #[allow(unused_mut)] // We only use the mut in cfg(test)
974 let mut should_process = !old_entry.was_processed;
975 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
977 // In test/fuzzing builds, we do extra checks to make sure the skipping
978 // of already-seen nodes only happens in cases we expect (see below).
979 if !should_process { should_process = true; }
983 let mut hop_use_fee_msat = 0;
984 let mut total_fee_msat = $next_hops_fee_msat;
986 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
987 // will have the same effective-fee
988 if $src_node_id != our_node_id {
989 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
990 // max_value means we'll always fail
991 // the old_entry.total_fee_msat > total_fee_msat check
992 None => total_fee_msat = u64::max_value(),
994 hop_use_fee_msat = fee_msat;
995 total_fee_msat += hop_use_fee_msat;
996 // When calculating the lowest inbound fees to a node, we
997 // calculate fees here not based on the actual value we think
998 // will flow over this channel, but on the minimum value that
999 // we'll accept flowing over it. The minimum accepted value
1000 // is a constant through each path collection run, ensuring
1001 // consistent basis. Otherwise we may later find a
1002 // different path to the source node that is more expensive,
1003 // but which we consider to be cheaper because we are capacity
1004 // constrained and the relative fee becomes lower.
1005 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1006 .map(|a| a.checked_add(total_fee_msat)) {
1011 total_fee_msat = u64::max_value();
1018 let path_penalty_msat = $next_hops_path_penalty_msat.saturating_add(
1019 scorer.channel_penalty_msat(short_channel_id, amount_to_transfer_over_msat,
1020 *available_liquidity_msat, &$src_node_id, &$dest_node_id));
1021 let new_graph_node = RouteGraphNode {
1022 node_id: $src_node_id,
1023 lowest_fee_to_peer_through_node: total_fee_msat,
1024 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1025 total_cltv_delta: hop_total_cltv_delta,
1026 value_contribution_msat: value_contribution_msat,
1027 path_htlc_minimum_msat,
1031 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1032 // if this way is cheaper than the already known
1033 // (considering the cost to "reach" this channel from the route destination,
1034 // the cost of using this channel,
1035 // and the cost of routing to the source node of this channel).
1036 // Also, consider that htlc_minimum_msat_difference, because we might end up
1037 // paying it. Consider the following exploit:
1038 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1039 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1040 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1041 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1043 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1044 // but it may require additional tracking - we don't want to double-count
1045 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1046 // can't use something that may decrease on future hops.
1047 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1048 .saturating_add(old_entry.path_penalty_msat);
1049 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1050 .saturating_add(path_penalty_msat);
1052 if !old_entry.was_processed && new_cost < old_cost {
1053 targets.push(new_graph_node);
1054 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1055 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1056 old_entry.total_fee_msat = total_fee_msat;
1057 old_entry.node_id = $dest_node_id.clone();
1058 old_entry.candidate = $candidate.clone();
1059 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1060 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1061 old_entry.path_penalty_msat = path_penalty_msat;
1062 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1064 old_entry.value_contribution_msat = value_contribution_msat;
1066 did_add_update_path_to_src_node = true;
1067 } else if old_entry.was_processed && new_cost < old_cost {
1068 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1070 // If we're skipping processing a node which was previously
1071 // processed even though we found another path to it with a
1072 // cheaper fee, check that it was because the second path we
1073 // found (which we are processing now) has a lower value
1074 // contribution due to an HTLC minimum limit.
1076 // e.g. take a graph with two paths from node 1 to node 2, one
1077 // through channel A, and one through channel B. Channel A and
1078 // B are both in the to-process heap, with their scores set by
1079 // a higher htlc_minimum than fee.
1080 // Channel A is processed first, and the channels onwards from
1081 // node 1 are added to the to-process heap. Thereafter, we pop
1082 // Channel B off of the heap, note that it has a much more
1083 // restrictive htlc_maximum_msat, and recalculate the fees for
1084 // all of node 1's channels using the new, reduced, amount.
1086 // This would be bogus - we'd be selecting a higher-fee path
1087 // with a lower htlc_maximum_msat instead of the one we'd
1088 // already decided to use.
1089 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1091 value_contribution_msat + path_penalty_msat <
1092 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1100 did_add_update_path_to_src_node
1104 let empty_node_features = NodeFeatures::empty();
1105 // Find ways (channels with destination) to reach a given node and store them
1106 // in the corresponding data structures (routing graph etc).
1107 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1108 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1109 // This data can later be helpful to optimize routing (pay lower fees).
1110 macro_rules! add_entries_to_cheapest_to_target_node {
1111 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => {
1112 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1113 let was_processed = elem.was_processed;
1114 elem.was_processed = true;
1117 // Entries are added to dist in add_entry!() when there is a channel from a node.
1118 // Because there are no channels from payee, it will not have a dist entry at this point.
1119 // If we're processing any other node, it is always be the result of a channel from it.
1120 assert_eq!($node_id, payee_node_id);
1125 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1126 for details in first_channels {
1127 let candidate = CandidateRouteHop::FirstHop { details };
1128 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1132 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1135 &empty_node_features
1138 if !features.requires_unknown_bits() {
1139 for chan_id in $node.channels.iter() {
1140 let chan = network_channels.get(chan_id).unwrap();
1141 if !chan.features.requires_unknown_bits() {
1142 let (directed_channel, source) =
1143 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1144 if first_hops.is_none() || *source != our_node_id {
1145 if let Some(direction) = directed_channel.direction() {
1146 if direction.enabled {
1147 let candidate = CandidateRouteHop::PublicHop {
1148 info: directed_channel.with_update().unwrap(),
1149 short_channel_id: *chan_id,
1151 add_entry!(candidate, *source, $node_id, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1162 let mut payment_paths = Vec::<PaymentPath>::new();
1164 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1165 'paths_collection: loop {
1166 // For every new path, start from scratch, except
1167 // bookkept_channels_liquidity_available_msat, which will improve
1168 // the further iterations of path finding. Also don't erase first_hop_targets.
1171 hit_minimum_limit = false;
1173 // If first hop is a private channel and the only way to reach the payee, this is the only
1174 // place where it could be added.
1175 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1176 for details in first_channels {
1177 let candidate = CandidateRouteHop::FirstHop { details };
1178 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1179 log_trace!(logger, "{} direct route to payee via SCID {}", if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1183 // Add the payee as a target, so that the payee-to-payer
1184 // search algorithm knows what to start with.
1185 match network_nodes.get(&payee_node_id) {
1186 // The payee is not in our network graph, so nothing to add here.
1187 // There is still a chance of reaching them via last_hops though,
1188 // so don't yet fail the payment here.
1189 // If not, targets.pop() will not even let us enter the loop in step 2.
1192 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1197 // If a caller provided us with last hops, add them to routing targets. Since this happens
1198 // earlier than general path finding, they will be somewhat prioritized, although currently
1199 // it matters only if the fees are exactly the same.
1200 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1201 let first_hop_in_route = &(route.0)[0];
1202 let have_hop_src_in_graph =
1203 // Only add the hops in this route to our candidate set if either
1204 // we have a direct channel to the first hop or the first hop is
1205 // in the regular network graph.
1206 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1207 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1208 if have_hop_src_in_graph {
1209 // We start building the path from reverse, i.e., from payee
1210 // to the first RouteHintHop in the path.
1211 let hop_iter = route.0.iter().rev();
1212 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1213 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1214 let mut hop_used = true;
1215 let mut aggregate_next_hops_fee_msat: u64 = 0;
1216 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1217 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1218 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1220 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1221 let source = NodeId::from_pubkey(&hop.src_node_id);
1222 let target = NodeId::from_pubkey(&prev_hop_id);
1223 let candidate = network_channels
1224 .get(&hop.short_channel_id)
1225 .and_then(|channel| channel.as_directed_to(&target))
1226 .and_then(|(channel, _)| channel.with_update())
1227 .map(|info| CandidateRouteHop::PublicHop {
1229 short_channel_id: hop.short_channel_id,
1231 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1232 let capacity_msat = candidate.effective_capacity().as_msat();
1233 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1234 .saturating_add(scorer.channel_penalty_msat(hop.short_channel_id, final_value_msat, capacity_msat, &source, &target));
1236 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1237 .saturating_add(hop.cltv_expiry_delta as u32);
1239 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta) {
1240 // If this hop was not used then there is no use checking the preceding hops
1241 // in the RouteHint. We can break by just searching for a direct channel between
1242 // last checked hop and first_hop_targets
1246 // Searching for a direct channel between last checked hop and first_hop_targets
1247 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1248 for details in first_channels {
1249 let candidate = CandidateRouteHop::FirstHop { details };
1250 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id), aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta);
1258 // In the next values of the iterator, the aggregate fees already reflects
1259 // the sum of value sent from payer (final_value_msat) and routing fees
1260 // for the last node in the RouteHint. We need to just add the fees to
1261 // route through the current node so that the preceeding node (next iteration)
1263 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1264 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1265 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1267 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1268 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1269 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1270 .checked_add(hop_htlc_minimum_msat_inc);
1271 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1273 if idx == route.0.len() - 1 {
1274 // The last hop in this iterator is the first hop in
1275 // overall RouteHint.
1276 // If this hop connects to a node with which we have a direct channel,
1277 // ignore the network graph and, if the last hop was added, add our
1278 // direct channel to the candidate set.
1280 // Note that we *must* check if the last hop was added as `add_entry`
1281 // always assumes that the third argument is a node to which we have a
1283 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1284 for details in first_channels {
1285 let candidate = CandidateRouteHop::FirstHop { details };
1286 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&hop.src_node_id), aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta);
1294 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1296 // At this point, targets are filled with the data from first and
1297 // last hops communicated by the caller, and the payment receiver.
1298 let mut found_new_path = false;
1301 // If this loop terminates due the exhaustion of targets, two situations are possible:
1302 // - not enough outgoing liquidity:
1303 // 0 < already_collected_value_msat < final_value_msat
1304 // - enough outgoing liquidity:
1305 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1306 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1307 // paths_collection will be stopped because found_new_path==false.
1308 // This is not necessarily a routing failure.
1309 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, .. }) = targets.pop() {
1311 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1312 // traversing the graph and arrange the path out of what we found.
1313 if node_id == our_node_id {
1314 let mut new_entry = dist.remove(&our_node_id).unwrap();
1315 let mut ordered_hops = vec!((new_entry.clone(), NodeFeatures::empty()));
1318 let mut features_set = false;
1319 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1320 for details in first_channels {
1321 if details.short_channel_id.unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1322 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1323 features_set = true;
1329 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1330 if let Some(node_info) = node.announcement_info.as_ref() {
1331 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1333 ordered_hops.last_mut().unwrap().1 = NodeFeatures::empty();
1336 // We can fill in features for everything except hops which were
1337 // provided via the invoice we're paying. We could guess based on the
1338 // recipient's features but for now we simply avoid guessing at all.
1342 // Means we succesfully traversed from the payer to the payee, now
1343 // save this path for the payment route. Also, update the liquidity
1344 // remaining on the used hops, so that we take them into account
1345 // while looking for more paths.
1346 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1350 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1351 Some(payment_hop) => payment_hop,
1352 // We can't arrive at None because, if we ever add an entry to targets,
1353 // we also fill in the entry in dist (see add_entry!).
1354 None => unreachable!(),
1356 // We "propagate" the fees one hop backward (topologically) here,
1357 // so that fees paid for a HTLC forwarding on the current channel are
1358 // associated with the previous channel (where they will be subtracted).
1359 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1360 ordered_hops.push((new_entry.clone(), NodeFeatures::empty()));
1362 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1363 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1365 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1366 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1368 let mut payment_path = PaymentPath {hops: ordered_hops};
1370 // We could have possibly constructed a slightly inconsistent path: since we reduce
1371 // value being transferred along the way, we could have violated htlc_minimum_msat
1372 // on some channels we already passed (assuming dest->source direction). Here, we
1373 // recompute the fees again, so that if that's the case, we match the currently
1374 // underpaid htlc_minimum_msat with fees.
1375 payment_path.update_value_and_recompute_fees(cmp::min(value_contribution_msat, final_value_msat));
1377 // Since a path allows to transfer as much value as
1378 // the smallest channel it has ("bottleneck"), we should recompute
1379 // the fees so sender HTLC don't overpay fees when traversing
1380 // larger channels than the bottleneck. This may happen because
1381 // when we were selecting those channels we were not aware how much value
1382 // this path will transfer, and the relative fee for them
1383 // might have been computed considering a larger value.
1384 // Remember that we used these channels so that we don't rely
1385 // on the same liquidity in future paths.
1386 let mut prevented_redundant_path_selection = false;
1387 for (payment_hop, _) in payment_path.hops.iter() {
1388 let channel_liquidity_available_msat = bookkept_channels_liquidity_available_msat.get_mut(&payment_hop.candidate.short_channel_id()).unwrap();
1389 let mut spent_on_hop_msat = value_contribution_msat;
1390 let next_hops_fee_msat = payment_hop.next_hops_fee_msat;
1391 spent_on_hop_msat += next_hops_fee_msat;
1392 if spent_on_hop_msat == *channel_liquidity_available_msat {
1393 // If this path used all of this channel's available liquidity, we know
1394 // this path will not be selected again in the next loop iteration.
1395 prevented_redundant_path_selection = true;
1397 *channel_liquidity_available_msat -= spent_on_hop_msat;
1399 if !prevented_redundant_path_selection {
1400 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1401 // we'll probably end up picking the same path again on the next iteration.
1402 // Decrease the available liquidity of a hop in the middle of the path.
1403 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1404 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1405 let victim_liquidity = bookkept_channels_liquidity_available_msat.get_mut(&victim_scid).unwrap();
1406 *victim_liquidity = 0;
1409 // Track the total amount all our collected paths allow to send so that we:
1410 // - know when to stop looking for more paths
1411 // - know which of the hops are useless considering how much more sats we need
1412 // (contributes_sufficient_value)
1413 already_collected_value_msat += value_contribution_msat;
1415 payment_paths.push(payment_path);
1416 found_new_path = true;
1417 break 'path_construction;
1420 // If we found a path back to the payee, we shouldn't try to process it again. This is
1421 // the equivalent of the `elem.was_processed` check in
1422 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1423 if node_id == payee_node_id { continue 'path_construction; }
1425 // Otherwise, since the current target node is not us,
1426 // keep "unrolling" the payment graph from payee to payer by
1427 // finding a way to reach the current target from the payer side.
1428 match network_nodes.get(&node_id) {
1431 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node, value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, total_cltv_delta);
1437 // If we don't support MPP, no use trying to gather more value ever.
1438 break 'paths_collection;
1442 // Stop either when the recommended value is reached or if no new path was found in this
1444 // In the latter case, making another path finding attempt won't help,
1445 // because we deterministically terminated the search due to low liquidity.
1446 if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1447 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1448 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1449 break 'paths_collection;
1450 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1451 // Further, if this was our first walk of the graph, and we weren't limited by an
1452 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1453 // limited by an htlc_minimum_msat value, find another path with a higher value,
1454 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1455 // still keeping a lower total fee than this path.
1456 if !hit_minimum_limit {
1457 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1458 break 'paths_collection;
1460 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1461 path_value_msat = recommended_value_msat;
1466 if payment_paths.len() == 0 {
1467 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1470 if already_collected_value_msat < final_value_msat {
1471 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1474 // Sort by total fees and take the best paths.
1475 payment_paths.sort_unstable_by_key(|path| path.get_total_fee_paid_msat());
1476 if payment_paths.len() > 50 {
1477 payment_paths.truncate(50);
1480 // Draw multiple sufficient routes by randomly combining the selected paths.
1481 let mut drawn_routes = Vec::new();
1482 let mut prng = ChaCha20::new(random_seed_bytes, &[0u8; 12]);
1483 let mut random_index_bytes = [0u8; ::core::mem::size_of::<usize>()];
1485 let num_permutations = payment_paths.len();
1486 for _ in 0..num_permutations {
1487 let mut cur_route = Vec::<PaymentPath>::new();
1488 let mut aggregate_route_value_msat = 0;
1491 // Do a Fisher-Yates shuffle to create a random permutation of the payment paths
1492 for cur_index in (1..payment_paths.len()).rev() {
1493 prng.process_in_place(&mut random_index_bytes);
1494 let random_index = usize::from_be_bytes(random_index_bytes).wrapping_rem(cur_index+1);
1495 payment_paths.swap(cur_index, random_index);
1499 for payment_path in &payment_paths {
1500 cur_route.push(payment_path.clone());
1501 aggregate_route_value_msat += payment_path.get_value_msat();
1502 if aggregate_route_value_msat > final_value_msat {
1503 // Last path likely overpaid. Substract it from the most expensive
1504 // (in terms of proportional fee) path in this route and recompute fees.
1505 // This might be not the most economically efficient way, but fewer paths
1506 // also makes routing more reliable.
1507 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1509 // First, we drop some expensive low-value paths entirely if possible, since fewer
1510 // paths is better: the payment is less likely to fail. In order to do so, we sort
1511 // by value and fall back to total fees paid, i.e., in case of equal values we
1512 // prefer lower cost paths.
1513 cur_route.sort_unstable_by(|a, b| {
1514 a.get_value_msat().cmp(&b.get_value_msat())
1515 // Reverse ordering for cost, so we drop higher-cost paths first
1516 .then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1519 // We should make sure that at least 1 path left.
1520 let mut paths_left = cur_route.len();
1521 cur_route.retain(|path| {
1522 if paths_left == 1 {
1525 let mut keep = true;
1526 let path_value_msat = path.get_value_msat();
1527 if path_value_msat <= overpaid_value_msat {
1529 overpaid_value_msat -= path_value_msat;
1535 if overpaid_value_msat == 0 {
1539 assert!(cur_route.len() > 0);
1542 // Now, subtract the overpaid value from the most-expensive path.
1543 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1544 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1545 cur_route.sort_unstable_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1546 let expensive_payment_path = cur_route.first_mut().unwrap();
1548 // We already dropped all the small value paths above, meaning all the
1549 // remaining paths are larger than remaining overpaid_value_msat.
1550 // Thus, this can't be negative.
1551 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1552 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1556 drawn_routes.push(cur_route);
1560 // Select the best route by lowest total cost.
1561 drawn_routes.sort_unstable_by_key(|paths| paths.iter().map(|path| path.get_cost_msat()).sum::<u64>());
1562 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1563 for payment_path in drawn_routes.first().unwrap() {
1564 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1566 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)})?,
1567 node_features: node_features.clone(),
1568 short_channel_id: payment_hop.candidate.short_channel_id(),
1569 channel_features: payment_hop.candidate.features(),
1570 fee_msat: payment_hop.fee_msat,
1571 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1573 }).collect::<Vec<_>>();
1574 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1575 // applicable for the previous hop.
1576 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1577 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1579 selected_paths.push(path);
1582 if let Some(features) = &payment_params.features {
1583 for path in selected_paths.iter_mut() {
1584 if let Ok(route_hop) = path.last_mut().unwrap() {
1585 route_hop.node_features = features.to_context();
1591 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1592 payment_params: Some(payment_params.clone()),
1594 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1598 // When an adversarial intermediary node observes a payment, it may be able to infer its
1599 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1600 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1601 // payment path by adding a randomized 'shadow route' offset to the final hop.
1602 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]) {
1603 let network_channels = network_graph.channels();
1604 let network_nodes = network_graph.nodes();
1606 for path in route.paths.iter_mut() {
1607 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1609 // Remember the last three nodes of the random walk and avoid looping back on them.
1610 // Init with the last three nodes from the actual path, if possible.
1611 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1612 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1613 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1615 // Choose the last publicly known node as the starting point for the random walk.
1616 let mut cur_hop: Option<NodeId> = None;
1617 let mut path_nonce = [0u8; 12];
1618 if let Some(starting_hop) = path.iter().rev()
1619 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1620 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1621 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1624 // Init PRNG with the path-dependant nonce, which is static for private paths.
1625 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1626 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1628 // Pick a random path length in [1 .. 3]
1629 prng.process_in_place(&mut random_path_bytes);
1630 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1632 for random_hop in 0..random_walk_length {
1633 // If we don't find a suitable offset in the public network graph, we default to
1634 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1635 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1637 if let Some(cur_node_id) = cur_hop {
1638 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1639 // Randomly choose the next unvisited hop.
1640 prng.process_in_place(&mut random_path_bytes);
1641 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1642 .checked_rem(cur_node.channels.len())
1643 .and_then(|index| cur_node.channels.get(index))
1644 .and_then(|id| network_channels.get(id)) {
1645 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1646 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1647 nodes_to_avoid[random_hop] = *next_id;
1648 dir_info.direction().map(|channel_update_info| {
1649 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1650 cur_hop = Some(*next_id);
1658 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1659 .checked_add(random_hop_offset)
1660 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1663 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1664 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1665 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1667 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1668 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1669 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1670 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1671 max_path_offset = cmp::max(
1672 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1673 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1674 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1676 // Add 'shadow' CLTV offset to the final hop
1677 if let Some(last_hop) = path.last_mut() {
1678 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1679 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1686 use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
1687 use routing::router::{get_route, add_random_cltv_offset, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA};
1688 use routing::scoring::Score;
1689 use chain::transaction::OutPoint;
1690 use chain::keysinterface::KeysInterface;
1691 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1692 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1693 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1694 use ln::channelmanager;
1695 use util::test_utils;
1696 use util::chacha20::ChaCha20;
1697 use util::ser::Writeable;
1699 use util::ser::Writer;
1701 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1702 use bitcoin::hashes::Hash;
1703 use bitcoin::network::constants::Network;
1704 use bitcoin::blockdata::constants::genesis_block;
1705 use bitcoin::blockdata::script::Builder;
1706 use bitcoin::blockdata::opcodes;
1707 use bitcoin::blockdata::transaction::TxOut;
1711 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
1712 use bitcoin::secp256k1::{Secp256k1, All};
1715 use sync::{self, Arc};
1717 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1718 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1719 channelmanager::ChannelDetails {
1720 channel_id: [0; 32],
1721 counterparty: channelmanager::ChannelCounterparty {
1724 unspendable_punishment_reserve: 0,
1725 forwarding_info: None,
1727 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1730 inbound_scid_alias: None,
1731 channel_value_satoshis: 0,
1734 outbound_capacity_msat,
1735 inbound_capacity_msat: 42,
1736 unspendable_punishment_reserve: None,
1737 confirmations_required: None,
1738 force_close_spend_delay: None,
1739 is_outbound: true, is_funding_locked: true,
1740 is_usable: true, is_public: true,
1744 // Using the same keys for LN and BTC ids
1746 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1747 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
1749 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
1750 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
1752 let unsigned_announcement = UnsignedChannelAnnouncement {
1754 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1758 bitcoin_key_1: node_id_1,
1759 bitcoin_key_2: node_id_2,
1760 excess_data: Vec::new(),
1763 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1764 let valid_announcement = ChannelAnnouncement {
1765 node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1766 node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1767 bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1768 bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1769 contents: unsigned_announcement.clone(),
1771 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
1772 Ok(res) => assert!(res),
1778 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1779 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
1781 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
1782 let valid_channel_update = ChannelUpdate {
1783 signature: secp_ctx.sign(&msghash, node_privkey),
1784 contents: update.clone()
1787 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
1788 Ok(res) => assert!(res),
1793 fn add_or_update_node(
1794 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1795 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
1797 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
1798 let unsigned_announcement = UnsignedNodeAnnouncement {
1804 addresses: Vec::new(),
1805 excess_address_data: Vec::new(),
1806 excess_data: Vec::new(),
1808 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1809 let valid_announcement = NodeAnnouncement {
1810 signature: secp_ctx.sign(&msghash, node_privkey),
1811 contents: unsigned_announcement.clone()
1814 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
1820 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
1821 let privkeys: Vec<SecretKey> = (2..10).map(|i| {
1822 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
1825 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
1827 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
1828 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
1830 (our_privkey, our_id, privkeys, pubkeys)
1833 fn id_to_feature_flags(id: u8) -> Vec<u8> {
1834 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1835 // test for it later.
1836 let idx = (id - 1) * 2 + 1;
1838 vec![1 << (idx - 8*3), 0, 0, 0]
1839 } else if idx > 8*2 {
1840 vec![1 << (idx - 8*2), 0, 0]
1841 } else if idx > 8*1 {
1842 vec![1 << (idx - 8*1), 0]
1848 fn build_graph() -> (
1850 sync::Arc<NetworkGraph>,
1851 NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
1852 sync::Arc<test_utils::TestChainSource>,
1853 sync::Arc<test_utils::TestLogger>,
1855 let secp_ctx = Secp256k1::new();
1856 let logger = Arc::new(test_utils::TestLogger::new());
1857 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
1858 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
1859 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
1860 // Build network from our_id to node6:
1862 // -1(1)2- node0 -1(3)2-
1864 // our_id -1(12)2- node7 -1(13)2--- node2
1866 // -1(2)2- node1 -1(4)2-
1869 // chan1 1-to-2: disabled
1870 // chan1 2-to-1: enabled, 0 fee
1872 // chan2 1-to-2: enabled, ignored fee
1873 // chan2 2-to-1: enabled, 0 fee
1875 // chan3 1-to-2: enabled, 0 fee
1876 // chan3 2-to-1: enabled, 100 msat fee
1878 // chan4 1-to-2: enabled, 100% fee
1879 // chan4 2-to-1: enabled, 0 fee
1881 // chan12 1-to-2: enabled, ignored fee
1882 // chan12 2-to-1: enabled, 0 fee
1884 // chan13 1-to-2: enabled, 200% fee
1885 // chan13 2-to-1: enabled, 0 fee
1888 // -1(5)2- node3 -1(8)2--
1892 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
1894 // -1(7)2- node5 -1(10)2-
1896 // Channels 5, 8, 9 and 10 are private channels.
1898 // chan5 1-to-2: enabled, 100 msat fee
1899 // chan5 2-to-1: enabled, 0 fee
1901 // chan6 1-to-2: enabled, 0 fee
1902 // chan6 2-to-1: enabled, 0 fee
1904 // chan7 1-to-2: enabled, 100% fee
1905 // chan7 2-to-1: enabled, 0 fee
1907 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
1908 // chan8 2-to-1: enabled, 0 fee
1910 // chan9 1-to-2: enabled, 1001 msat fee
1911 // chan9 2-to-1: enabled, 0 fee
1913 // chan10 1-to-2: enabled, 0 fee
1914 // chan10 2-to-1: enabled, 0 fee
1916 // chan11 1-to-2: enabled, 0 fee
1917 // chan11 2-to-1: enabled, 0 fee
1919 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
1921 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
1922 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1923 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1924 short_channel_id: 1,
1927 cltv_expiry_delta: 0,
1928 htlc_minimum_msat: 0,
1929 htlc_maximum_msat: OptionalField::Absent,
1931 fee_proportional_millionths: 0,
1932 excess_data: Vec::new()
1935 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
1937 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
1938 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1939 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1940 short_channel_id: 2,
1943 cltv_expiry_delta: (5 << 4) | 3,
1944 htlc_minimum_msat: 0,
1945 htlc_maximum_msat: OptionalField::Absent,
1946 fee_base_msat: u32::max_value(),
1947 fee_proportional_millionths: u32::max_value(),
1948 excess_data: Vec::new()
1950 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
1951 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1952 short_channel_id: 2,
1955 cltv_expiry_delta: 0,
1956 htlc_minimum_msat: 0,
1957 htlc_maximum_msat: OptionalField::Absent,
1959 fee_proportional_millionths: 0,
1960 excess_data: Vec::new()
1963 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
1965 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
1966 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1967 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1968 short_channel_id: 12,
1971 cltv_expiry_delta: (5 << 4) | 3,
1972 htlc_minimum_msat: 0,
1973 htlc_maximum_msat: OptionalField::Absent,
1974 fee_base_msat: u32::max_value(),
1975 fee_proportional_millionths: u32::max_value(),
1976 excess_data: Vec::new()
1978 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
1979 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1980 short_channel_id: 12,
1983 cltv_expiry_delta: 0,
1984 htlc_minimum_msat: 0,
1985 htlc_maximum_msat: OptionalField::Absent,
1987 fee_proportional_millionths: 0,
1988 excess_data: Vec::new()
1991 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
1993 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
1994 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1995 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1996 short_channel_id: 3,
1999 cltv_expiry_delta: (3 << 4) | 1,
2000 htlc_minimum_msat: 0,
2001 htlc_maximum_msat: OptionalField::Absent,
2003 fee_proportional_millionths: 0,
2004 excess_data: Vec::new()
2006 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2008 short_channel_id: 3,
2011 cltv_expiry_delta: (3 << 4) | 2,
2012 htlc_minimum_msat: 0,
2013 htlc_maximum_msat: OptionalField::Absent,
2015 fee_proportional_millionths: 0,
2016 excess_data: Vec::new()
2019 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2020 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2021 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2022 short_channel_id: 4,
2025 cltv_expiry_delta: (4 << 4) | 1,
2026 htlc_minimum_msat: 0,
2027 htlc_maximum_msat: OptionalField::Absent,
2029 fee_proportional_millionths: 1000000,
2030 excess_data: Vec::new()
2032 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2033 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2034 short_channel_id: 4,
2037 cltv_expiry_delta: (4 << 4) | 2,
2038 htlc_minimum_msat: 0,
2039 htlc_maximum_msat: OptionalField::Absent,
2041 fee_proportional_millionths: 0,
2042 excess_data: Vec::new()
2045 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2046 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2047 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2048 short_channel_id: 13,
2051 cltv_expiry_delta: (13 << 4) | 1,
2052 htlc_minimum_msat: 0,
2053 htlc_maximum_msat: OptionalField::Absent,
2055 fee_proportional_millionths: 2000000,
2056 excess_data: Vec::new()
2058 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2059 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2060 short_channel_id: 13,
2063 cltv_expiry_delta: (13 << 4) | 2,
2064 htlc_minimum_msat: 0,
2065 htlc_maximum_msat: OptionalField::Absent,
2067 fee_proportional_millionths: 0,
2068 excess_data: Vec::new()
2071 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2073 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2074 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2075 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2076 short_channel_id: 6,
2079 cltv_expiry_delta: (6 << 4) | 1,
2080 htlc_minimum_msat: 0,
2081 htlc_maximum_msat: OptionalField::Absent,
2083 fee_proportional_millionths: 0,
2084 excess_data: Vec::new()
2086 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2087 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2088 short_channel_id: 6,
2091 cltv_expiry_delta: (6 << 4) | 2,
2092 htlc_minimum_msat: 0,
2093 htlc_maximum_msat: OptionalField::Absent,
2095 fee_proportional_millionths: 0,
2096 excess_data: Vec::new(),
2099 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2100 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2101 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2102 short_channel_id: 11,
2105 cltv_expiry_delta: (11 << 4) | 1,
2106 htlc_minimum_msat: 0,
2107 htlc_maximum_msat: OptionalField::Absent,
2109 fee_proportional_millionths: 0,
2110 excess_data: Vec::new()
2112 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2113 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2114 short_channel_id: 11,
2117 cltv_expiry_delta: (11 << 4) | 2,
2118 htlc_minimum_msat: 0,
2119 htlc_maximum_msat: OptionalField::Absent,
2121 fee_proportional_millionths: 0,
2122 excess_data: Vec::new()
2125 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2127 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2129 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2130 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2131 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2132 short_channel_id: 7,
2135 cltv_expiry_delta: (7 << 4) | 1,
2136 htlc_minimum_msat: 0,
2137 htlc_maximum_msat: OptionalField::Absent,
2139 fee_proportional_millionths: 1000000,
2140 excess_data: Vec::new()
2142 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2144 short_channel_id: 7,
2147 cltv_expiry_delta: (7 << 4) | 2,
2148 htlc_minimum_msat: 0,
2149 htlc_maximum_msat: OptionalField::Absent,
2151 fee_proportional_millionths: 0,
2152 excess_data: Vec::new()
2155 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2157 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
2161 fn simple_route_test() {
2162 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2163 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2164 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2165 let scorer = test_utils::TestScorer::with_penalty(0);
2166 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2167 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2169 // Simple route to 2 via 1
2171 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) {
2172 assert_eq!(err, "Cannot send a payment of 0 msat");
2173 } else { panic!(); }
2175 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2176 assert_eq!(route.paths[0].len(), 2);
2178 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2179 assert_eq!(route.paths[0][0].short_channel_id, 2);
2180 assert_eq!(route.paths[0][0].fee_msat, 100);
2181 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2182 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2183 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2185 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2186 assert_eq!(route.paths[0][1].short_channel_id, 4);
2187 assert_eq!(route.paths[0][1].fee_msat, 100);
2188 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2189 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2190 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2194 fn invalid_first_hop_test() {
2195 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2196 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2197 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2198 let scorer = test_utils::TestScorer::with_penalty(0);
2199 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2200 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2202 // Simple route to 2 via 1
2204 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2206 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2207 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) {
2208 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2209 } else { panic!(); }
2211 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2212 assert_eq!(route.paths[0].len(), 2);
2216 fn htlc_minimum_test() {
2217 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2218 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2219 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2220 let scorer = test_utils::TestScorer::with_penalty(0);
2221 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2222 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2224 // Simple route to 2 via 1
2226 // Disable other paths
2227 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2228 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2229 short_channel_id: 12,
2231 flags: 2, // to disable
2232 cltv_expiry_delta: 0,
2233 htlc_minimum_msat: 0,
2234 htlc_maximum_msat: OptionalField::Absent,
2236 fee_proportional_millionths: 0,
2237 excess_data: Vec::new()
2239 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2240 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2241 short_channel_id: 3,
2243 flags: 2, // to disable
2244 cltv_expiry_delta: 0,
2245 htlc_minimum_msat: 0,
2246 htlc_maximum_msat: OptionalField::Absent,
2248 fee_proportional_millionths: 0,
2249 excess_data: Vec::new()
2251 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2252 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2253 short_channel_id: 13,
2255 flags: 2, // to disable
2256 cltv_expiry_delta: 0,
2257 htlc_minimum_msat: 0,
2258 htlc_maximum_msat: OptionalField::Absent,
2260 fee_proportional_millionths: 0,
2261 excess_data: Vec::new()
2263 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2265 short_channel_id: 6,
2267 flags: 2, // to disable
2268 cltv_expiry_delta: 0,
2269 htlc_minimum_msat: 0,
2270 htlc_maximum_msat: OptionalField::Absent,
2272 fee_proportional_millionths: 0,
2273 excess_data: Vec::new()
2275 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2276 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2277 short_channel_id: 7,
2279 flags: 2, // to disable
2280 cltv_expiry_delta: 0,
2281 htlc_minimum_msat: 0,
2282 htlc_maximum_msat: OptionalField::Absent,
2284 fee_proportional_millionths: 0,
2285 excess_data: Vec::new()
2288 // Check against amount_to_transfer_over_msat.
2289 // Set minimal HTLC of 200_000_000 msat.
2290 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2291 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2292 short_channel_id: 2,
2295 cltv_expiry_delta: 0,
2296 htlc_minimum_msat: 200_000_000,
2297 htlc_maximum_msat: OptionalField::Absent,
2299 fee_proportional_millionths: 0,
2300 excess_data: Vec::new()
2303 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2305 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2306 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2307 short_channel_id: 4,
2310 cltv_expiry_delta: 0,
2311 htlc_minimum_msat: 0,
2312 htlc_maximum_msat: OptionalField::Present(199_999_999),
2314 fee_proportional_millionths: 0,
2315 excess_data: Vec::new()
2318 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2319 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) {
2320 assert_eq!(err, "Failed to find a path to the given destination");
2321 } else { panic!(); }
2323 // Lift the restriction on the first hop.
2324 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2325 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2326 short_channel_id: 2,
2329 cltv_expiry_delta: 0,
2330 htlc_minimum_msat: 0,
2331 htlc_maximum_msat: OptionalField::Absent,
2333 fee_proportional_millionths: 0,
2334 excess_data: Vec::new()
2337 // A payment above the minimum should pass
2338 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();
2339 assert_eq!(route.paths[0].len(), 2);
2343 fn htlc_minimum_overpay_test() {
2344 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2345 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2346 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2347 let scorer = test_utils::TestScorer::with_penalty(0);
2348 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2349 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2351 // A route to node#2 via two paths.
2352 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2353 // Thus, they can't send 60 without overpaying.
2354 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2355 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2356 short_channel_id: 2,
2359 cltv_expiry_delta: 0,
2360 htlc_minimum_msat: 35_000,
2361 htlc_maximum_msat: OptionalField::Present(40_000),
2363 fee_proportional_millionths: 0,
2364 excess_data: Vec::new()
2366 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2367 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2368 short_channel_id: 12,
2371 cltv_expiry_delta: 0,
2372 htlc_minimum_msat: 35_000,
2373 htlc_maximum_msat: OptionalField::Present(40_000),
2375 fee_proportional_millionths: 0,
2376 excess_data: Vec::new()
2380 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2381 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2382 short_channel_id: 13,
2385 cltv_expiry_delta: 0,
2386 htlc_minimum_msat: 0,
2387 htlc_maximum_msat: OptionalField::Absent,
2389 fee_proportional_millionths: 0,
2390 excess_data: Vec::new()
2392 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2393 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2394 short_channel_id: 4,
2397 cltv_expiry_delta: 0,
2398 htlc_minimum_msat: 0,
2399 htlc_maximum_msat: OptionalField::Absent,
2401 fee_proportional_millionths: 0,
2402 excess_data: Vec::new()
2405 // Disable other paths
2406 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2407 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2408 short_channel_id: 1,
2410 flags: 2, // to disable
2411 cltv_expiry_delta: 0,
2412 htlc_minimum_msat: 0,
2413 htlc_maximum_msat: OptionalField::Absent,
2415 fee_proportional_millionths: 0,
2416 excess_data: Vec::new()
2419 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2420 // Overpay fees to hit htlc_minimum_msat.
2421 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2422 // TODO: this could be better balanced to overpay 10k and not 15k.
2423 assert_eq!(overpaid_fees, 15_000);
2425 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2426 // while taking even more fee to match htlc_minimum_msat.
2427 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2428 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2429 short_channel_id: 12,
2432 cltv_expiry_delta: 0,
2433 htlc_minimum_msat: 65_000,
2434 htlc_maximum_msat: OptionalField::Present(80_000),
2436 fee_proportional_millionths: 0,
2437 excess_data: Vec::new()
2439 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2440 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2441 short_channel_id: 2,
2444 cltv_expiry_delta: 0,
2445 htlc_minimum_msat: 0,
2446 htlc_maximum_msat: OptionalField::Absent,
2448 fee_proportional_millionths: 0,
2449 excess_data: Vec::new()
2451 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2452 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2453 short_channel_id: 4,
2456 cltv_expiry_delta: 0,
2457 htlc_minimum_msat: 0,
2458 htlc_maximum_msat: OptionalField::Absent,
2460 fee_proportional_millionths: 100_000,
2461 excess_data: Vec::new()
2464 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2465 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2466 assert_eq!(route.paths.len(), 1);
2467 assert_eq!(route.paths[0][0].short_channel_id, 12);
2468 let fees = route.paths[0][0].fee_msat;
2469 assert_eq!(fees, 5_000);
2471 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2472 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2473 // the other channel.
2474 assert_eq!(route.paths.len(), 1);
2475 assert_eq!(route.paths[0][0].short_channel_id, 2);
2476 let fees = route.paths[0][0].fee_msat;
2477 assert_eq!(fees, 5_000);
2481 fn disable_channels_test() {
2482 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2483 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2484 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2485 let scorer = test_utils::TestScorer::with_penalty(0);
2486 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2487 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2489 // // Disable channels 4 and 12 by flags=2
2490 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2491 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2492 short_channel_id: 4,
2494 flags: 2, // to disable
2495 cltv_expiry_delta: 0,
2496 htlc_minimum_msat: 0,
2497 htlc_maximum_msat: OptionalField::Absent,
2499 fee_proportional_millionths: 0,
2500 excess_data: Vec::new()
2502 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2503 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2504 short_channel_id: 12,
2506 flags: 2, // to disable
2507 cltv_expiry_delta: 0,
2508 htlc_minimum_msat: 0,
2509 htlc_maximum_msat: OptionalField::Absent,
2511 fee_proportional_millionths: 0,
2512 excess_data: Vec::new()
2515 // If all the channels require some features we don't understand, route should fail
2516 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) {
2517 assert_eq!(err, "Failed to find a path to the given destination");
2518 } else { panic!(); }
2520 // If we specify a channel to node7, that overrides our local channel view and that gets used
2521 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2522 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();
2523 assert_eq!(route.paths[0].len(), 2);
2525 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2526 assert_eq!(route.paths[0][0].short_channel_id, 42);
2527 assert_eq!(route.paths[0][0].fee_msat, 200);
2528 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2529 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2530 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2532 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2533 assert_eq!(route.paths[0][1].short_channel_id, 13);
2534 assert_eq!(route.paths[0][1].fee_msat, 100);
2535 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2536 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2537 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2541 fn disable_node_test() {
2542 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2543 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2544 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2545 let scorer = test_utils::TestScorer::with_penalty(0);
2546 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2547 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2549 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2550 let mut unknown_features = NodeFeatures::known();
2551 unknown_features.set_unknown_feature_required();
2552 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2553 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2554 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2556 // If all nodes require some features we don't understand, route should fail
2557 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) {
2558 assert_eq!(err, "Failed to find a path to the given destination");
2559 } else { panic!(); }
2561 // If we specify a channel to node7, that overrides our local channel view and that gets used
2562 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2563 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();
2564 assert_eq!(route.paths[0].len(), 2);
2566 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2567 assert_eq!(route.paths[0][0].short_channel_id, 42);
2568 assert_eq!(route.paths[0][0].fee_msat, 200);
2569 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2570 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2571 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2573 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2574 assert_eq!(route.paths[0][1].short_channel_id, 13);
2575 assert_eq!(route.paths[0][1].fee_msat, 100);
2576 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2577 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2578 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2580 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2581 // naively) assume that the user checked the feature bits on the invoice, which override
2582 // the node_announcement.
2586 fn our_chans_test() {
2587 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2588 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2589 let scorer = test_utils::TestScorer::with_penalty(0);
2590 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2591 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2593 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2594 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2595 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2596 assert_eq!(route.paths[0].len(), 3);
2598 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2599 assert_eq!(route.paths[0][0].short_channel_id, 2);
2600 assert_eq!(route.paths[0][0].fee_msat, 200);
2601 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2602 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2603 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2605 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2606 assert_eq!(route.paths[0][1].short_channel_id, 4);
2607 assert_eq!(route.paths[0][1].fee_msat, 100);
2608 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2609 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2610 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2612 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2613 assert_eq!(route.paths[0][2].short_channel_id, 3);
2614 assert_eq!(route.paths[0][2].fee_msat, 100);
2615 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2616 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2617 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2619 // If we specify a channel to node7, that overrides our local channel view and that gets used
2620 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2621 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2622 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();
2623 assert_eq!(route.paths[0].len(), 2);
2625 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2626 assert_eq!(route.paths[0][0].short_channel_id, 42);
2627 assert_eq!(route.paths[0][0].fee_msat, 200);
2628 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2629 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2630 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2632 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2633 assert_eq!(route.paths[0][1].short_channel_id, 13);
2634 assert_eq!(route.paths[0][1].fee_msat, 100);
2635 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2636 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2637 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2640 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2641 let zero_fees = RoutingFees {
2643 proportional_millionths: 0,
2645 vec![RouteHint(vec![RouteHintHop {
2646 src_node_id: nodes[3],
2647 short_channel_id: 8,
2649 cltv_expiry_delta: (8 << 4) | 1,
2650 htlc_minimum_msat: None,
2651 htlc_maximum_msat: None,
2653 ]), RouteHint(vec![RouteHintHop {
2654 src_node_id: nodes[4],
2655 short_channel_id: 9,
2658 proportional_millionths: 0,
2660 cltv_expiry_delta: (9 << 4) | 1,
2661 htlc_minimum_msat: None,
2662 htlc_maximum_msat: None,
2663 }]), RouteHint(vec![RouteHintHop {
2664 src_node_id: nodes[5],
2665 short_channel_id: 10,
2667 cltv_expiry_delta: (10 << 4) | 1,
2668 htlc_minimum_msat: None,
2669 htlc_maximum_msat: None,
2673 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2674 let zero_fees = RoutingFees {
2676 proportional_millionths: 0,
2678 vec![RouteHint(vec![RouteHintHop {
2679 src_node_id: nodes[2],
2680 short_channel_id: 5,
2683 proportional_millionths: 0,
2685 cltv_expiry_delta: (5 << 4) | 1,
2686 htlc_minimum_msat: None,
2687 htlc_maximum_msat: None,
2689 src_node_id: nodes[3],
2690 short_channel_id: 8,
2692 cltv_expiry_delta: (8 << 4) | 1,
2693 htlc_minimum_msat: None,
2694 htlc_maximum_msat: None,
2696 ]), RouteHint(vec![RouteHintHop {
2697 src_node_id: nodes[4],
2698 short_channel_id: 9,
2701 proportional_millionths: 0,
2703 cltv_expiry_delta: (9 << 4) | 1,
2704 htlc_minimum_msat: None,
2705 htlc_maximum_msat: None,
2706 }]), RouteHint(vec![RouteHintHop {
2707 src_node_id: nodes[5],
2708 short_channel_id: 10,
2710 cltv_expiry_delta: (10 << 4) | 1,
2711 htlc_minimum_msat: None,
2712 htlc_maximum_msat: None,
2717 fn partial_route_hint_test() {
2718 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2719 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2720 let scorer = test_utils::TestScorer::with_penalty(0);
2721 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2722 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2724 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2725 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2726 // RouteHint may be partially used by the algo to build the best path.
2728 // First check that last hop can't have its source as the payee.
2729 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2730 src_node_id: nodes[6],
2731 short_channel_id: 8,
2734 proportional_millionths: 0,
2736 cltv_expiry_delta: (8 << 4) | 1,
2737 htlc_minimum_msat: None,
2738 htlc_maximum_msat: None,
2741 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2742 invalid_last_hops.push(invalid_last_hop);
2744 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2745 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) {
2746 assert_eq!(err, "Route hint cannot have the payee as the source.");
2747 } else { panic!(); }
2750 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2751 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2752 assert_eq!(route.paths[0].len(), 5);
2754 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2755 assert_eq!(route.paths[0][0].short_channel_id, 2);
2756 assert_eq!(route.paths[0][0].fee_msat, 100);
2757 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2758 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2759 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2761 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2762 assert_eq!(route.paths[0][1].short_channel_id, 4);
2763 assert_eq!(route.paths[0][1].fee_msat, 0);
2764 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2765 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2766 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2768 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2769 assert_eq!(route.paths[0][2].short_channel_id, 6);
2770 assert_eq!(route.paths[0][2].fee_msat, 0);
2771 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2772 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2773 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2775 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2776 assert_eq!(route.paths[0][3].short_channel_id, 11);
2777 assert_eq!(route.paths[0][3].fee_msat, 0);
2778 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2779 // If we have a peer in the node map, we'll use their features here since we don't have
2780 // a way of figuring out their features from the invoice:
2781 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2782 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2784 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2785 assert_eq!(route.paths[0][4].short_channel_id, 8);
2786 assert_eq!(route.paths[0][4].fee_msat, 100);
2787 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2788 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2789 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2792 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2793 let zero_fees = RoutingFees {
2795 proportional_millionths: 0,
2797 vec![RouteHint(vec![RouteHintHop {
2798 src_node_id: nodes[3],
2799 short_channel_id: 8,
2801 cltv_expiry_delta: (8 << 4) | 1,
2802 htlc_minimum_msat: None,
2803 htlc_maximum_msat: None,
2804 }]), RouteHint(vec![
2806 ]), RouteHint(vec![RouteHintHop {
2807 src_node_id: nodes[5],
2808 short_channel_id: 10,
2810 cltv_expiry_delta: (10 << 4) | 1,
2811 htlc_minimum_msat: None,
2812 htlc_maximum_msat: None,
2817 fn ignores_empty_last_hops_test() {
2818 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2819 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2820 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2821 let scorer = test_utils::TestScorer::with_penalty(0);
2822 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2823 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2825 // Test handling of an empty RouteHint passed in Invoice.
2827 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2828 assert_eq!(route.paths[0].len(), 5);
2830 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2831 assert_eq!(route.paths[0][0].short_channel_id, 2);
2832 assert_eq!(route.paths[0][0].fee_msat, 100);
2833 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2834 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2835 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2837 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2838 assert_eq!(route.paths[0][1].short_channel_id, 4);
2839 assert_eq!(route.paths[0][1].fee_msat, 0);
2840 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2841 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2842 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2844 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2845 assert_eq!(route.paths[0][2].short_channel_id, 6);
2846 assert_eq!(route.paths[0][2].fee_msat, 0);
2847 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2848 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2849 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2851 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2852 assert_eq!(route.paths[0][3].short_channel_id, 11);
2853 assert_eq!(route.paths[0][3].fee_msat, 0);
2854 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2855 // If we have a peer in the node map, we'll use their features here since we don't have
2856 // a way of figuring out their features from the invoice:
2857 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2858 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2860 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2861 assert_eq!(route.paths[0][4].short_channel_id, 8);
2862 assert_eq!(route.paths[0][4].fee_msat, 100);
2863 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2864 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2865 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2868 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2870 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2871 let zero_fees = RoutingFees {
2873 proportional_millionths: 0,
2875 vec![RouteHint(vec![RouteHintHop {
2876 src_node_id: hint_hops[0],
2877 short_channel_id: 0xff00,
2880 proportional_millionths: 0,
2882 cltv_expiry_delta: (5 << 4) | 1,
2883 htlc_minimum_msat: None,
2884 htlc_maximum_msat: None,
2886 src_node_id: hint_hops[1],
2887 short_channel_id: 0xff01,
2889 cltv_expiry_delta: (8 << 4) | 1,
2890 htlc_minimum_msat: None,
2891 htlc_maximum_msat: None,
2896 fn multi_hint_last_hops_test() {
2897 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2898 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2899 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2900 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2901 let scorer = test_utils::TestScorer::with_penalty(0);
2902 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2903 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2904 // Test through channels 2, 3, 0xff00, 0xff01.
2905 // Test shows that multiple hop hints are considered.
2907 // Disabling channels 6 & 7 by flags=2
2908 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2909 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2910 short_channel_id: 6,
2912 flags: 2, // to disable
2913 cltv_expiry_delta: 0,
2914 htlc_minimum_msat: 0,
2915 htlc_maximum_msat: OptionalField::Absent,
2917 fee_proportional_millionths: 0,
2918 excess_data: Vec::new()
2920 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2921 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2922 short_channel_id: 7,
2924 flags: 2, // to disable
2925 cltv_expiry_delta: 0,
2926 htlc_minimum_msat: 0,
2927 htlc_maximum_msat: OptionalField::Absent,
2929 fee_proportional_millionths: 0,
2930 excess_data: Vec::new()
2933 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2934 assert_eq!(route.paths[0].len(), 4);
2936 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2937 assert_eq!(route.paths[0][0].short_channel_id, 2);
2938 assert_eq!(route.paths[0][0].fee_msat, 200);
2939 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2940 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2941 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2943 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2944 assert_eq!(route.paths[0][1].short_channel_id, 4);
2945 assert_eq!(route.paths[0][1].fee_msat, 100);
2946 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2947 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2948 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2950 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2951 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2952 assert_eq!(route.paths[0][2].fee_msat, 0);
2953 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2954 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2955 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2957 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2958 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2959 assert_eq!(route.paths[0][3].fee_msat, 100);
2960 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2961 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2962 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2966 fn private_multi_hint_last_hops_test() {
2967 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2968 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2970 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
2971 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
2973 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
2974 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2975 let scorer = test_utils::TestScorer::with_penalty(0);
2976 // Test through channels 2, 3, 0xff00, 0xff01.
2977 // Test shows that multiple hop hints are considered.
2979 // Disabling channels 6 & 7 by flags=2
2980 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2981 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2982 short_channel_id: 6,
2984 flags: 2, // to disable
2985 cltv_expiry_delta: 0,
2986 htlc_minimum_msat: 0,
2987 htlc_maximum_msat: OptionalField::Absent,
2989 fee_proportional_millionths: 0,
2990 excess_data: Vec::new()
2992 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2993 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2994 short_channel_id: 7,
2996 flags: 2, // to disable
2997 cltv_expiry_delta: 0,
2998 htlc_minimum_msat: 0,
2999 htlc_maximum_msat: OptionalField::Absent,
3001 fee_proportional_millionths: 0,
3002 excess_data: Vec::new()
3005 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3006 assert_eq!(route.paths[0].len(), 4);
3008 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3009 assert_eq!(route.paths[0][0].short_channel_id, 2);
3010 assert_eq!(route.paths[0][0].fee_msat, 200);
3011 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3012 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3013 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3015 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3016 assert_eq!(route.paths[0][1].short_channel_id, 4);
3017 assert_eq!(route.paths[0][1].fee_msat, 100);
3018 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3019 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3020 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3022 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3023 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3024 assert_eq!(route.paths[0][2].fee_msat, 0);
3025 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3026 assert_eq!(route.paths[0][2].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3027 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3029 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3030 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3031 assert_eq!(route.paths[0][3].fee_msat, 100);
3032 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3033 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3034 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3037 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3038 let zero_fees = RoutingFees {
3040 proportional_millionths: 0,
3042 vec![RouteHint(vec![RouteHintHop {
3043 src_node_id: nodes[4],
3044 short_channel_id: 11,
3046 cltv_expiry_delta: (11 << 4) | 1,
3047 htlc_minimum_msat: None,
3048 htlc_maximum_msat: None,
3050 src_node_id: nodes[3],
3051 short_channel_id: 8,
3053 cltv_expiry_delta: (8 << 4) | 1,
3054 htlc_minimum_msat: None,
3055 htlc_maximum_msat: None,
3056 }]), RouteHint(vec![RouteHintHop {
3057 src_node_id: nodes[4],
3058 short_channel_id: 9,
3061 proportional_millionths: 0,
3063 cltv_expiry_delta: (9 << 4) | 1,
3064 htlc_minimum_msat: None,
3065 htlc_maximum_msat: None,
3066 }]), RouteHint(vec![RouteHintHop {
3067 src_node_id: nodes[5],
3068 short_channel_id: 10,
3070 cltv_expiry_delta: (10 << 4) | 1,
3071 htlc_minimum_msat: None,
3072 htlc_maximum_msat: None,
3077 fn last_hops_with_public_channel_test() {
3078 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3079 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3080 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3081 let scorer = test_utils::TestScorer::with_penalty(0);
3082 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3083 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3084 // This test shows that public routes can be present in the invoice
3085 // which would be handled in the same manner.
3087 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3088 assert_eq!(route.paths[0].len(), 5);
3090 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3091 assert_eq!(route.paths[0][0].short_channel_id, 2);
3092 assert_eq!(route.paths[0][0].fee_msat, 100);
3093 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3094 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3095 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3097 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3098 assert_eq!(route.paths[0][1].short_channel_id, 4);
3099 assert_eq!(route.paths[0][1].fee_msat, 0);
3100 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3101 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3102 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3104 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3105 assert_eq!(route.paths[0][2].short_channel_id, 6);
3106 assert_eq!(route.paths[0][2].fee_msat, 0);
3107 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3108 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3109 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3111 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3112 assert_eq!(route.paths[0][3].short_channel_id, 11);
3113 assert_eq!(route.paths[0][3].fee_msat, 0);
3114 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3115 // If we have a peer in the node map, we'll use their features here since we don't have
3116 // a way of figuring out their features from the invoice:
3117 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3118 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3120 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3121 assert_eq!(route.paths[0][4].short_channel_id, 8);
3122 assert_eq!(route.paths[0][4].fee_msat, 100);
3123 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3124 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3125 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3129 fn our_chans_last_hop_connect_test() {
3130 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3131 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3132 let scorer = test_utils::TestScorer::with_penalty(0);
3133 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3134 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3136 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3137 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3138 let mut last_hops = last_hops(&nodes);
3139 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3140 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();
3141 assert_eq!(route.paths[0].len(), 2);
3143 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3144 assert_eq!(route.paths[0][0].short_channel_id, 42);
3145 assert_eq!(route.paths[0][0].fee_msat, 0);
3146 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3147 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3148 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3150 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3151 assert_eq!(route.paths[0][1].short_channel_id, 8);
3152 assert_eq!(route.paths[0][1].fee_msat, 100);
3153 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3154 assert_eq!(route.paths[0][1].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3155 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3157 last_hops[0].0[0].fees.base_msat = 1000;
3159 // Revert to via 6 as the fee on 8 goes up
3160 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3161 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3162 assert_eq!(route.paths[0].len(), 4);
3164 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3165 assert_eq!(route.paths[0][0].short_channel_id, 2);
3166 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3167 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3168 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3169 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3171 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3172 assert_eq!(route.paths[0][1].short_channel_id, 4);
3173 assert_eq!(route.paths[0][1].fee_msat, 100);
3174 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3175 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3176 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3178 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3179 assert_eq!(route.paths[0][2].short_channel_id, 7);
3180 assert_eq!(route.paths[0][2].fee_msat, 0);
3181 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3182 // If we have a peer in the node map, we'll use their features here since we don't have
3183 // a way of figuring out their features from the invoice:
3184 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3185 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3187 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3188 assert_eq!(route.paths[0][3].short_channel_id, 10);
3189 assert_eq!(route.paths[0][3].fee_msat, 100);
3190 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3191 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3192 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3194 // ...but still use 8 for larger payments as 6 has a variable feerate
3195 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3196 assert_eq!(route.paths[0].len(), 5);
3198 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3199 assert_eq!(route.paths[0][0].short_channel_id, 2);
3200 assert_eq!(route.paths[0][0].fee_msat, 3000);
3201 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3202 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3203 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3205 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3206 assert_eq!(route.paths[0][1].short_channel_id, 4);
3207 assert_eq!(route.paths[0][1].fee_msat, 0);
3208 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3209 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3210 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3212 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3213 assert_eq!(route.paths[0][2].short_channel_id, 6);
3214 assert_eq!(route.paths[0][2].fee_msat, 0);
3215 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3216 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3217 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3219 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3220 assert_eq!(route.paths[0][3].short_channel_id, 11);
3221 assert_eq!(route.paths[0][3].fee_msat, 1000);
3222 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3223 // If we have a peer in the node map, we'll use their features here since we don't have
3224 // a way of figuring out their features from the invoice:
3225 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3226 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3228 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3229 assert_eq!(route.paths[0][4].short_channel_id, 8);
3230 assert_eq!(route.paths[0][4].fee_msat, 2000);
3231 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3232 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3233 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3236 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> {
3237 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3238 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3239 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3241 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3242 let last_hops = RouteHint(vec![RouteHintHop {
3243 src_node_id: middle_node_id,
3244 short_channel_id: 8,
3247 proportional_millionths: last_hop_fee_prop,
3249 cltv_expiry_delta: (8 << 4) | 1,
3250 htlc_minimum_msat: None,
3251 htlc_maximum_msat: last_hop_htlc_max,
3253 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3254 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3255 let scorer = test_utils::TestScorer::with_penalty(0);
3256 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3257 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3258 get_route(&source_node_id, &payment_params, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()).read_only(),
3259 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes)
3263 fn unannounced_path_test() {
3264 // We should be able to send a payment to a destination without any help of a routing graph
3265 // if we have a channel with a common counterparty that appears in the first and last hop
3267 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3269 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3270 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3271 assert_eq!(route.paths[0].len(), 2);
3273 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3274 assert_eq!(route.paths[0][0].short_channel_id, 42);
3275 assert_eq!(route.paths[0][0].fee_msat, 1001);
3276 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3277 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3278 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3280 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3281 assert_eq!(route.paths[0][1].short_channel_id, 8);
3282 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3283 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3284 assert_eq!(route.paths[0][1].node_features.le_flags(), &[0; 0]); // We dont pass flags in from invoices yet
3285 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3289 fn overflow_unannounced_path_test_liquidity_underflow() {
3290 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3291 // the last-hop had a fee which overflowed a u64, we'd panic.
3292 // This was due to us adding the first-hop from us unconditionally, causing us to think
3293 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3294 // In this test, we previously hit a subtraction underflow due to having less available
3295 // liquidity at the last hop than 0.
3296 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());
3300 fn overflow_unannounced_path_test_feerate_overflow() {
3301 // This tests for the same case as above, except instead of hitting a subtraction
3302 // underflow, we hit a case where the fee charged at a hop overflowed.
3303 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());
3307 fn available_amount_while_routing_test() {
3308 // Tests whether we choose the correct available channel amount while routing.
3310 let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
3311 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3312 let scorer = test_utils::TestScorer::with_penalty(0);
3313 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3314 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3315 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3317 // We will use a simple single-path route from
3318 // our node to node2 via node0: channels {1, 3}.
3320 // First disable all other paths.
3321 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3322 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3323 short_channel_id: 2,
3326 cltv_expiry_delta: 0,
3327 htlc_minimum_msat: 0,
3328 htlc_maximum_msat: OptionalField::Present(100_000),
3330 fee_proportional_millionths: 0,
3331 excess_data: Vec::new()
3333 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3334 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3335 short_channel_id: 12,
3338 cltv_expiry_delta: 0,
3339 htlc_minimum_msat: 0,
3340 htlc_maximum_msat: OptionalField::Present(100_000),
3342 fee_proportional_millionths: 0,
3343 excess_data: Vec::new()
3346 // Make the first channel (#1) very permissive,
3347 // and we will be testing all limits on the second channel.
3348 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3349 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3350 short_channel_id: 1,
3353 cltv_expiry_delta: 0,
3354 htlc_minimum_msat: 0,
3355 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3357 fee_proportional_millionths: 0,
3358 excess_data: Vec::new()
3361 // First, let's see if routing works if we have absolutely no idea about the available amount.
3362 // In this case, it should be set to 250_000 sats.
3363 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3364 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3365 short_channel_id: 3,
3368 cltv_expiry_delta: 0,
3369 htlc_minimum_msat: 0,
3370 htlc_maximum_msat: OptionalField::Absent,
3372 fee_proportional_millionths: 0,
3373 excess_data: Vec::new()
3377 // Attempt to route more than available results in a failure.
3378 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3379 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3380 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3381 } else { panic!(); }
3385 // Now, attempt to route an exact amount we have should be fine.
3386 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();
3387 assert_eq!(route.paths.len(), 1);
3388 let path = route.paths.last().unwrap();
3389 assert_eq!(path.len(), 2);
3390 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3391 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3394 // Check that setting outbound_capacity_msat in first_hops limits the channels.
3395 // Disable channel #1 and use another first hop.
3396 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3397 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3398 short_channel_id: 1,
3401 cltv_expiry_delta: 0,
3402 htlc_minimum_msat: 0,
3403 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3405 fee_proportional_millionths: 0,
3406 excess_data: Vec::new()
3409 // Now, limit the first_hop by the outbound_capacity_msat of 200_000 sats.
3410 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3413 // Attempt to route more than available results in a failure.
3414 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3415 &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) {
3416 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3417 } else { panic!(); }
3421 // Now, attempt to route an exact amount we have should be fine.
3422 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();
3423 assert_eq!(route.paths.len(), 1);
3424 let path = route.paths.last().unwrap();
3425 assert_eq!(path.len(), 2);
3426 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3427 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3430 // Enable channel #1 back.
3431 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3432 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3433 short_channel_id: 1,
3436 cltv_expiry_delta: 0,
3437 htlc_minimum_msat: 0,
3438 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3440 fee_proportional_millionths: 0,
3441 excess_data: Vec::new()
3445 // Now let's see if routing works if we know only htlc_maximum_msat.
3446 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3447 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3448 short_channel_id: 3,
3451 cltv_expiry_delta: 0,
3452 htlc_minimum_msat: 0,
3453 htlc_maximum_msat: OptionalField::Present(15_000),
3455 fee_proportional_millionths: 0,
3456 excess_data: Vec::new()
3460 // Attempt to route more than available results in a failure.
3461 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3462 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3463 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3464 } else { panic!(); }
3468 // Now, attempt to route an exact amount we have should be fine.
3469 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3470 assert_eq!(route.paths.len(), 1);
3471 let path = route.paths.last().unwrap();
3472 assert_eq!(path.len(), 2);
3473 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3474 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3477 // Now let's see if routing works if we know only capacity from the UTXO.
3479 // We can't change UTXO capacity on the fly, so we'll disable
3480 // the existing channel and add another one with the capacity we need.
3481 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3482 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3483 short_channel_id: 3,
3486 cltv_expiry_delta: 0,
3487 htlc_minimum_msat: 0,
3488 htlc_maximum_msat: OptionalField::Absent,
3490 fee_proportional_millionths: 0,
3491 excess_data: Vec::new()
3494 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3495 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3496 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3497 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3498 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3500 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3501 net_graph_msg_handler.add_chain_access(Some(chain_monitor));
3503 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3504 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3505 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3506 short_channel_id: 333,
3509 cltv_expiry_delta: (3 << 4) | 1,
3510 htlc_minimum_msat: 0,
3511 htlc_maximum_msat: OptionalField::Absent,
3513 fee_proportional_millionths: 0,
3514 excess_data: Vec::new()
3516 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3517 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3518 short_channel_id: 333,
3521 cltv_expiry_delta: (3 << 4) | 2,
3522 htlc_minimum_msat: 0,
3523 htlc_maximum_msat: OptionalField::Absent,
3525 fee_proportional_millionths: 0,
3526 excess_data: Vec::new()
3530 // Attempt to route more than available results in a failure.
3531 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3532 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3533 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3534 } else { panic!(); }
3538 // Now, attempt to route an exact amount we have should be fine.
3539 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3540 assert_eq!(route.paths.len(), 1);
3541 let path = route.paths.last().unwrap();
3542 assert_eq!(path.len(), 2);
3543 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3544 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3547 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3548 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3549 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3550 short_channel_id: 333,
3553 cltv_expiry_delta: 0,
3554 htlc_minimum_msat: 0,
3555 htlc_maximum_msat: OptionalField::Present(10_000),
3557 fee_proportional_millionths: 0,
3558 excess_data: Vec::new()
3562 // Attempt to route more than available results in a failure.
3563 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3564 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3565 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3566 } else { panic!(); }
3570 // Now, attempt to route an exact amount we have should be fine.
3571 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3572 assert_eq!(route.paths.len(), 1);
3573 let path = route.paths.last().unwrap();
3574 assert_eq!(path.len(), 2);
3575 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3576 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3581 fn available_liquidity_last_hop_test() {
3582 // Check that available liquidity properly limits the path even when only
3583 // one of the latter hops is limited.
3584 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3585 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3586 let scorer = test_utils::TestScorer::with_penalty(0);
3587 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3588 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3589 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3591 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3592 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3593 // Total capacity: 50 sats.
3595 // Disable other potential paths.
3596 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3598 short_channel_id: 2,
3601 cltv_expiry_delta: 0,
3602 htlc_minimum_msat: 0,
3603 htlc_maximum_msat: OptionalField::Present(100_000),
3605 fee_proportional_millionths: 0,
3606 excess_data: Vec::new()
3608 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3609 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3610 short_channel_id: 7,
3613 cltv_expiry_delta: 0,
3614 htlc_minimum_msat: 0,
3615 htlc_maximum_msat: OptionalField::Present(100_000),
3617 fee_proportional_millionths: 0,
3618 excess_data: Vec::new()
3623 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3624 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3625 short_channel_id: 12,
3628 cltv_expiry_delta: 0,
3629 htlc_minimum_msat: 0,
3630 htlc_maximum_msat: OptionalField::Present(100_000),
3632 fee_proportional_millionths: 0,
3633 excess_data: Vec::new()
3635 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3636 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3637 short_channel_id: 13,
3640 cltv_expiry_delta: 0,
3641 htlc_minimum_msat: 0,
3642 htlc_maximum_msat: OptionalField::Present(100_000),
3644 fee_proportional_millionths: 0,
3645 excess_data: Vec::new()
3648 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3649 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3650 short_channel_id: 6,
3653 cltv_expiry_delta: 0,
3654 htlc_minimum_msat: 0,
3655 htlc_maximum_msat: OptionalField::Present(50_000),
3657 fee_proportional_millionths: 0,
3658 excess_data: Vec::new()
3660 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3661 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3662 short_channel_id: 11,
3665 cltv_expiry_delta: 0,
3666 htlc_minimum_msat: 0,
3667 htlc_maximum_msat: OptionalField::Present(100_000),
3669 fee_proportional_millionths: 0,
3670 excess_data: Vec::new()
3673 // Attempt to route more than available results in a failure.
3674 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3675 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3676 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3677 } else { panic!(); }
3681 // Now, attempt to route 49 sats (just a bit below the capacity).
3682 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3683 assert_eq!(route.paths.len(), 1);
3684 let mut total_amount_paid_msat = 0;
3685 for path in &route.paths {
3686 assert_eq!(path.len(), 4);
3687 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3688 total_amount_paid_msat += path.last().unwrap().fee_msat;
3690 assert_eq!(total_amount_paid_msat, 49_000);
3694 // Attempt to route an exact amount is also fine
3695 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3696 assert_eq!(route.paths.len(), 1);
3697 let mut total_amount_paid_msat = 0;
3698 for path in &route.paths {
3699 assert_eq!(path.len(), 4);
3700 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3701 total_amount_paid_msat += path.last().unwrap().fee_msat;
3703 assert_eq!(total_amount_paid_msat, 50_000);
3708 fn ignore_fee_first_hop_test() {
3709 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3710 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3711 let scorer = test_utils::TestScorer::with_penalty(0);
3712 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3713 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3714 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3716 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3717 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3718 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3719 short_channel_id: 1,
3722 cltv_expiry_delta: 0,
3723 htlc_minimum_msat: 0,
3724 htlc_maximum_msat: OptionalField::Present(100_000),
3725 fee_base_msat: 1_000_000,
3726 fee_proportional_millionths: 0,
3727 excess_data: Vec::new()
3729 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3730 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3731 short_channel_id: 3,
3734 cltv_expiry_delta: 0,
3735 htlc_minimum_msat: 0,
3736 htlc_maximum_msat: OptionalField::Present(50_000),
3738 fee_proportional_millionths: 0,
3739 excess_data: Vec::new()
3743 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3744 assert_eq!(route.paths.len(), 1);
3745 let mut total_amount_paid_msat = 0;
3746 for path in &route.paths {
3747 assert_eq!(path.len(), 2);
3748 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3749 total_amount_paid_msat += path.last().unwrap().fee_msat;
3751 assert_eq!(total_amount_paid_msat, 50_000);
3756 fn simple_mpp_route_test() {
3757 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3758 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3759 let scorer = test_utils::TestScorer::with_penalty(0);
3760 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3761 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3762 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3764 // We need a route consisting of 3 paths:
3765 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3766 // To achieve this, the amount being transferred should be around
3767 // the total capacity of these 3 paths.
3769 // First, we set limits on these (previously unlimited) channels.
3770 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3772 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3773 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3774 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3775 short_channel_id: 1,
3778 cltv_expiry_delta: 0,
3779 htlc_minimum_msat: 0,
3780 htlc_maximum_msat: OptionalField::Present(100_000),
3782 fee_proportional_millionths: 0,
3783 excess_data: Vec::new()
3785 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3786 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3787 short_channel_id: 3,
3790 cltv_expiry_delta: 0,
3791 htlc_minimum_msat: 0,
3792 htlc_maximum_msat: OptionalField::Present(50_000),
3794 fee_proportional_millionths: 0,
3795 excess_data: Vec::new()
3798 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3799 // (total limit 60).
3800 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3801 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3802 short_channel_id: 12,
3805 cltv_expiry_delta: 0,
3806 htlc_minimum_msat: 0,
3807 htlc_maximum_msat: OptionalField::Present(60_000),
3809 fee_proportional_millionths: 0,
3810 excess_data: Vec::new()
3812 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3813 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3814 short_channel_id: 13,
3817 cltv_expiry_delta: 0,
3818 htlc_minimum_msat: 0,
3819 htlc_maximum_msat: OptionalField::Present(60_000),
3821 fee_proportional_millionths: 0,
3822 excess_data: Vec::new()
3825 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3826 // (total capacity 180 sats).
3827 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3828 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3829 short_channel_id: 2,
3832 cltv_expiry_delta: 0,
3833 htlc_minimum_msat: 0,
3834 htlc_maximum_msat: OptionalField::Present(200_000),
3836 fee_proportional_millionths: 0,
3837 excess_data: Vec::new()
3839 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3840 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3841 short_channel_id: 4,
3844 cltv_expiry_delta: 0,
3845 htlc_minimum_msat: 0,
3846 htlc_maximum_msat: OptionalField::Present(180_000),
3848 fee_proportional_millionths: 0,
3849 excess_data: Vec::new()
3853 // Attempt to route more than available results in a failure.
3854 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3855 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3856 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3857 } else { panic!(); }
3861 // Now, attempt to route 250 sats (just a bit below the capacity).
3862 // Our algorithm should provide us with these 3 paths.
3863 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3864 assert_eq!(route.paths.len(), 3);
3865 let mut total_amount_paid_msat = 0;
3866 for path in &route.paths {
3867 assert_eq!(path.len(), 2);
3868 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3869 total_amount_paid_msat += path.last().unwrap().fee_msat;
3871 assert_eq!(total_amount_paid_msat, 250_000);
3875 // Attempt to route an exact amount is also fine
3876 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3877 assert_eq!(route.paths.len(), 3);
3878 let mut total_amount_paid_msat = 0;
3879 for path in &route.paths {
3880 assert_eq!(path.len(), 2);
3881 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3882 total_amount_paid_msat += path.last().unwrap().fee_msat;
3884 assert_eq!(total_amount_paid_msat, 290_000);
3889 fn long_mpp_route_test() {
3890 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3891 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3892 let scorer = test_utils::TestScorer::with_penalty(0);
3893 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3894 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3895 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3897 // We need a route consisting of 3 paths:
3898 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3899 // Note that these paths overlap (channels 5, 12, 13).
3900 // We will route 300 sats.
3901 // Each path will have 100 sats capacity, those channels which
3902 // are used twice will have 200 sats capacity.
3904 // Disable other potential paths.
3905 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3906 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3907 short_channel_id: 2,
3910 cltv_expiry_delta: 0,
3911 htlc_minimum_msat: 0,
3912 htlc_maximum_msat: OptionalField::Present(100_000),
3914 fee_proportional_millionths: 0,
3915 excess_data: Vec::new()
3917 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3918 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3919 short_channel_id: 7,
3922 cltv_expiry_delta: 0,
3923 htlc_minimum_msat: 0,
3924 htlc_maximum_msat: OptionalField::Present(100_000),
3926 fee_proportional_millionths: 0,
3927 excess_data: Vec::new()
3930 // Path via {node0, node2} is channels {1, 3, 5}.
3931 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3932 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3933 short_channel_id: 1,
3936 cltv_expiry_delta: 0,
3937 htlc_minimum_msat: 0,
3938 htlc_maximum_msat: OptionalField::Present(100_000),
3940 fee_proportional_millionths: 0,
3941 excess_data: Vec::new()
3943 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3944 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3945 short_channel_id: 3,
3948 cltv_expiry_delta: 0,
3949 htlc_minimum_msat: 0,
3950 htlc_maximum_msat: OptionalField::Present(100_000),
3952 fee_proportional_millionths: 0,
3953 excess_data: Vec::new()
3956 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3957 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3958 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3959 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3960 short_channel_id: 5,
3963 cltv_expiry_delta: 0,
3964 htlc_minimum_msat: 0,
3965 htlc_maximum_msat: OptionalField::Present(200_000),
3967 fee_proportional_millionths: 0,
3968 excess_data: Vec::new()
3971 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3972 // Add 100 sats to the capacities of {12, 13}, because these channels
3973 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3974 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3975 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3976 short_channel_id: 12,
3979 cltv_expiry_delta: 0,
3980 htlc_minimum_msat: 0,
3981 htlc_maximum_msat: OptionalField::Present(200_000),
3983 fee_proportional_millionths: 0,
3984 excess_data: Vec::new()
3986 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3987 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3988 short_channel_id: 13,
3991 cltv_expiry_delta: 0,
3992 htlc_minimum_msat: 0,
3993 htlc_maximum_msat: OptionalField::Present(200_000),
3995 fee_proportional_millionths: 0,
3996 excess_data: Vec::new()
3999 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4000 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4001 short_channel_id: 6,
4004 cltv_expiry_delta: 0,
4005 htlc_minimum_msat: 0,
4006 htlc_maximum_msat: OptionalField::Present(100_000),
4008 fee_proportional_millionths: 0,
4009 excess_data: Vec::new()
4011 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4012 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4013 short_channel_id: 11,
4016 cltv_expiry_delta: 0,
4017 htlc_minimum_msat: 0,
4018 htlc_maximum_msat: OptionalField::Present(100_000),
4020 fee_proportional_millionths: 0,
4021 excess_data: Vec::new()
4024 // Path via {node7, node2} is channels {12, 13, 5}.
4025 // We already limited them to 200 sats (they are used twice for 100 sats).
4026 // Nothing to do here.
4029 // Attempt to route more than available results in a failure.
4030 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4031 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4032 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4033 } else { panic!(); }
4037 // Now, attempt to route 300 sats (exact amount we can route).
4038 // Our algorithm should provide us with these 3 paths, 100 sats each.
4039 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4040 assert_eq!(route.paths.len(), 3);
4042 let mut total_amount_paid_msat = 0;
4043 for path in &route.paths {
4044 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4045 total_amount_paid_msat += path.last().unwrap().fee_msat;
4047 assert_eq!(total_amount_paid_msat, 300_000);
4053 fn mpp_cheaper_route_test() {
4054 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4055 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4056 let scorer = test_utils::TestScorer::with_penalty(0);
4057 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4058 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4059 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4061 // This test checks that if we have two cheaper paths and one more expensive path,
4062 // so that liquidity-wise any 2 of 3 combination is sufficient,
4063 // two cheaper paths will be taken.
4064 // These paths have equal available liquidity.
4066 // We need a combination of 3 paths:
4067 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4068 // Note that these paths overlap (channels 5, 12, 13).
4069 // Each path will have 100 sats capacity, those channels which
4070 // are used twice will have 200 sats capacity.
4072 // Disable other potential paths.
4073 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4074 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4075 short_channel_id: 2,
4078 cltv_expiry_delta: 0,
4079 htlc_minimum_msat: 0,
4080 htlc_maximum_msat: OptionalField::Present(100_000),
4082 fee_proportional_millionths: 0,
4083 excess_data: Vec::new()
4085 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4086 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4087 short_channel_id: 7,
4090 cltv_expiry_delta: 0,
4091 htlc_minimum_msat: 0,
4092 htlc_maximum_msat: OptionalField::Present(100_000),
4094 fee_proportional_millionths: 0,
4095 excess_data: Vec::new()
4098 // Path via {node0, node2} is channels {1, 3, 5}.
4099 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4100 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4101 short_channel_id: 1,
4104 cltv_expiry_delta: 0,
4105 htlc_minimum_msat: 0,
4106 htlc_maximum_msat: OptionalField::Present(100_000),
4108 fee_proportional_millionths: 0,
4109 excess_data: Vec::new()
4111 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4112 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4113 short_channel_id: 3,
4116 cltv_expiry_delta: 0,
4117 htlc_minimum_msat: 0,
4118 htlc_maximum_msat: OptionalField::Present(100_000),
4120 fee_proportional_millionths: 0,
4121 excess_data: Vec::new()
4124 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4125 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4126 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4127 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4128 short_channel_id: 5,
4131 cltv_expiry_delta: 0,
4132 htlc_minimum_msat: 0,
4133 htlc_maximum_msat: OptionalField::Present(200_000),
4135 fee_proportional_millionths: 0,
4136 excess_data: Vec::new()
4139 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4140 // Add 100 sats to the capacities of {12, 13}, because these channels
4141 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4142 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4144 short_channel_id: 12,
4147 cltv_expiry_delta: 0,
4148 htlc_minimum_msat: 0,
4149 htlc_maximum_msat: OptionalField::Present(200_000),
4151 fee_proportional_millionths: 0,
4152 excess_data: Vec::new()
4154 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4156 short_channel_id: 13,
4159 cltv_expiry_delta: 0,
4160 htlc_minimum_msat: 0,
4161 htlc_maximum_msat: OptionalField::Present(200_000),
4163 fee_proportional_millionths: 0,
4164 excess_data: Vec::new()
4167 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4168 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4169 short_channel_id: 6,
4172 cltv_expiry_delta: 0,
4173 htlc_minimum_msat: 0,
4174 htlc_maximum_msat: OptionalField::Present(100_000),
4175 fee_base_msat: 1_000,
4176 fee_proportional_millionths: 0,
4177 excess_data: Vec::new()
4179 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4180 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4181 short_channel_id: 11,
4184 cltv_expiry_delta: 0,
4185 htlc_minimum_msat: 0,
4186 htlc_maximum_msat: OptionalField::Present(100_000),
4188 fee_proportional_millionths: 0,
4189 excess_data: Vec::new()
4192 // Path via {node7, node2} is channels {12, 13, 5}.
4193 // We already limited them to 200 sats (they are used twice for 100 sats).
4194 // Nothing to do here.
4197 // Now, attempt to route 180 sats.
4198 // Our algorithm should provide us with these 2 paths.
4199 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4200 assert_eq!(route.paths.len(), 2);
4202 let mut total_value_transferred_msat = 0;
4203 let mut total_paid_msat = 0;
4204 for path in &route.paths {
4205 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4206 total_value_transferred_msat += path.last().unwrap().fee_msat;
4208 total_paid_msat += hop.fee_msat;
4211 // If we paid fee, this would be higher.
4212 assert_eq!(total_value_transferred_msat, 180_000);
4213 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4214 assert_eq!(total_fees_paid, 0);
4219 fn fees_on_mpp_route_test() {
4220 // This test makes sure that MPP algorithm properly takes into account
4221 // fees charged on the channels, by making the fees impactful:
4222 // if the fee is not properly accounted for, the behavior is different.
4223 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4224 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4225 let scorer = test_utils::TestScorer::with_penalty(0);
4226 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4227 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4228 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4230 // We need a route consisting of 2 paths:
4231 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4232 // We will route 200 sats, Each path will have 100 sats capacity.
4234 // This test is not particularly stable: e.g.,
4235 // there's a way to route via {node0, node2, node4}.
4236 // It works while pathfinding is deterministic, but can be broken otherwise.
4237 // It's fine to ignore this concern for now.
4239 // Disable other potential paths.
4240 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4241 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4242 short_channel_id: 2,
4245 cltv_expiry_delta: 0,
4246 htlc_minimum_msat: 0,
4247 htlc_maximum_msat: OptionalField::Present(100_000),
4249 fee_proportional_millionths: 0,
4250 excess_data: Vec::new()
4253 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4254 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4255 short_channel_id: 7,
4258 cltv_expiry_delta: 0,
4259 htlc_minimum_msat: 0,
4260 htlc_maximum_msat: OptionalField::Present(100_000),
4262 fee_proportional_millionths: 0,
4263 excess_data: Vec::new()
4266 // Path via {node0, node2} is channels {1, 3, 5}.
4267 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4268 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4269 short_channel_id: 1,
4272 cltv_expiry_delta: 0,
4273 htlc_minimum_msat: 0,
4274 htlc_maximum_msat: OptionalField::Present(100_000),
4276 fee_proportional_millionths: 0,
4277 excess_data: Vec::new()
4279 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4280 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4281 short_channel_id: 3,
4284 cltv_expiry_delta: 0,
4285 htlc_minimum_msat: 0,
4286 htlc_maximum_msat: OptionalField::Present(100_000),
4288 fee_proportional_millionths: 0,
4289 excess_data: Vec::new()
4292 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4293 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4294 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4295 short_channel_id: 5,
4298 cltv_expiry_delta: 0,
4299 htlc_minimum_msat: 0,
4300 htlc_maximum_msat: OptionalField::Present(100_000),
4302 fee_proportional_millionths: 0,
4303 excess_data: Vec::new()
4306 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4307 // All channels should be 100 sats capacity. But for the fee experiment,
4308 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4309 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4310 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4311 // so no matter how large are other channels,
4312 // the whole path will be limited by 100 sats with just these 2 conditions:
4313 // - channel 12 capacity is 250 sats
4314 // - fee for channel 6 is 150 sats
4315 // Let's test this by enforcing these 2 conditions and removing other limits.
4316 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4317 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4318 short_channel_id: 12,
4321 cltv_expiry_delta: 0,
4322 htlc_minimum_msat: 0,
4323 htlc_maximum_msat: OptionalField::Present(250_000),
4325 fee_proportional_millionths: 0,
4326 excess_data: Vec::new()
4328 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4329 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4330 short_channel_id: 13,
4333 cltv_expiry_delta: 0,
4334 htlc_minimum_msat: 0,
4335 htlc_maximum_msat: OptionalField::Absent,
4337 fee_proportional_millionths: 0,
4338 excess_data: Vec::new()
4341 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4342 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4343 short_channel_id: 6,
4346 cltv_expiry_delta: 0,
4347 htlc_minimum_msat: 0,
4348 htlc_maximum_msat: OptionalField::Absent,
4349 fee_base_msat: 150_000,
4350 fee_proportional_millionths: 0,
4351 excess_data: Vec::new()
4353 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4354 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4355 short_channel_id: 11,
4358 cltv_expiry_delta: 0,
4359 htlc_minimum_msat: 0,
4360 htlc_maximum_msat: OptionalField::Absent,
4362 fee_proportional_millionths: 0,
4363 excess_data: Vec::new()
4367 // Attempt to route more than available results in a failure.
4368 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4369 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4370 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4371 } else { panic!(); }
4375 // Now, attempt to route 200 sats (exact amount we can route).
4376 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4377 assert_eq!(route.paths.len(), 2);
4379 let mut total_amount_paid_msat = 0;
4380 for path in &route.paths {
4381 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4382 total_amount_paid_msat += path.last().unwrap().fee_msat;
4384 assert_eq!(total_amount_paid_msat, 200_000);
4385 assert_eq!(route.get_total_fees(), 150_000);
4390 fn mpp_with_last_hops() {
4391 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4392 // via a single last-hop route hint, we'd fail to route if we first collected routes
4393 // totaling close but not quite enough to fund the full payment.
4395 // This was because we considered last-hop hints to have exactly the sought payment amount
4396 // instead of the amount we were trying to collect, needlessly limiting our path searching
4397 // at the very first hop.
4399 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4400 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4401 // to only have the remaining to-collect amount in available liquidity.
4403 // This bug appeared in production in some specific channel configurations.
4404 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4405 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4406 let scorer = test_utils::TestScorer::with_penalty(0);
4407 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4408 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4409 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4410 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4411 src_node_id: nodes[2],
4412 short_channel_id: 42,
4413 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4414 cltv_expiry_delta: 42,
4415 htlc_minimum_msat: None,
4416 htlc_maximum_msat: None,
4419 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4420 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4421 // would first use the no-fee route and then fail to find a path along the second route as
4422 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4423 // under 5% of our payment amount.
4424 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4425 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4426 short_channel_id: 1,
4429 cltv_expiry_delta: (5 << 4) | 5,
4430 htlc_minimum_msat: 0,
4431 htlc_maximum_msat: OptionalField::Present(99_000),
4432 fee_base_msat: u32::max_value(),
4433 fee_proportional_millionths: u32::max_value(),
4434 excess_data: Vec::new()
4436 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4437 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4438 short_channel_id: 2,
4441 cltv_expiry_delta: (5 << 4) | 3,
4442 htlc_minimum_msat: 0,
4443 htlc_maximum_msat: OptionalField::Present(99_000),
4444 fee_base_msat: u32::max_value(),
4445 fee_proportional_millionths: u32::max_value(),
4446 excess_data: Vec::new()
4448 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4449 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4450 short_channel_id: 4,
4453 cltv_expiry_delta: (4 << 4) | 1,
4454 htlc_minimum_msat: 0,
4455 htlc_maximum_msat: OptionalField::Absent,
4457 fee_proportional_millionths: 0,
4458 excess_data: Vec::new()
4460 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4461 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4462 short_channel_id: 13,
4464 flags: 0|2, // Channel disabled
4465 cltv_expiry_delta: (13 << 4) | 1,
4466 htlc_minimum_msat: 0,
4467 htlc_maximum_msat: OptionalField::Absent,
4469 fee_proportional_millionths: 2000000,
4470 excess_data: Vec::new()
4473 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4475 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4476 assert_eq!(route.paths.len(), 2);
4477 // Paths are somewhat randomly ordered, but:
4478 // * the first is channel 2 (1 msat fee) -> channel 4 -> channel 42
4479 // * the second is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4480 assert_eq!(route.paths[0][0].short_channel_id, 2);
4481 assert_eq!(route.paths[0][0].fee_msat, 1);
4482 assert_eq!(route.paths[0][2].fee_msat, 1_000);
4483 assert_eq!(route.paths[1][0].short_channel_id, 1);
4484 assert_eq!(route.paths[1][0].fee_msat, 0);
4485 assert_eq!(route.paths[1][2].fee_msat, 99_000);
4486 assert_eq!(route.get_total_fees(), 1);
4487 assert_eq!(route.get_total_amount(), 100_000);
4491 fn drop_lowest_channel_mpp_route_test() {
4492 // This test checks that low-capacity channel is dropped when after
4493 // path finding we realize that we found more capacity than we need.
4494 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4495 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4496 let scorer = test_utils::TestScorer::with_penalty(0);
4497 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4498 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4499 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4501 // We need a route consisting of 3 paths:
4502 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4504 // The first and the second paths should be sufficient, but the third should be
4505 // cheaper, so that we select it but drop later.
4507 // First, we set limits on these (previously unlimited) channels.
4508 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4510 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4511 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4512 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4513 short_channel_id: 1,
4516 cltv_expiry_delta: 0,
4517 htlc_minimum_msat: 0,
4518 htlc_maximum_msat: OptionalField::Present(100_000),
4520 fee_proportional_millionths: 0,
4521 excess_data: Vec::new()
4523 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4524 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4525 short_channel_id: 3,
4528 cltv_expiry_delta: 0,
4529 htlc_minimum_msat: 0,
4530 htlc_maximum_msat: OptionalField::Present(50_000),
4532 fee_proportional_millionths: 0,
4533 excess_data: Vec::new()
4536 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4537 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4538 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4539 short_channel_id: 12,
4542 cltv_expiry_delta: 0,
4543 htlc_minimum_msat: 0,
4544 htlc_maximum_msat: OptionalField::Present(60_000),
4546 fee_proportional_millionths: 0,
4547 excess_data: Vec::new()
4549 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4550 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4551 short_channel_id: 13,
4554 cltv_expiry_delta: 0,
4555 htlc_minimum_msat: 0,
4556 htlc_maximum_msat: OptionalField::Present(60_000),
4558 fee_proportional_millionths: 0,
4559 excess_data: Vec::new()
4562 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4563 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4565 short_channel_id: 2,
4568 cltv_expiry_delta: 0,
4569 htlc_minimum_msat: 0,
4570 htlc_maximum_msat: OptionalField::Present(20_000),
4572 fee_proportional_millionths: 0,
4573 excess_data: Vec::new()
4575 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4577 short_channel_id: 4,
4580 cltv_expiry_delta: 0,
4581 htlc_minimum_msat: 0,
4582 htlc_maximum_msat: OptionalField::Present(20_000),
4584 fee_proportional_millionths: 0,
4585 excess_data: Vec::new()
4589 // Attempt to route more than available results in a failure.
4590 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4591 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4592 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4593 } else { panic!(); }
4597 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4598 // Our algorithm should provide us with these 3 paths.
4599 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4600 assert_eq!(route.paths.len(), 3);
4601 let mut total_amount_paid_msat = 0;
4602 for path in &route.paths {
4603 assert_eq!(path.len(), 2);
4604 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4605 total_amount_paid_msat += path.last().unwrap().fee_msat;
4607 assert_eq!(total_amount_paid_msat, 125_000);
4611 // Attempt to route without the last small cheap channel
4612 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4613 assert_eq!(route.paths.len(), 2);
4614 let mut total_amount_paid_msat = 0;
4615 for path in &route.paths {
4616 assert_eq!(path.len(), 2);
4617 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4618 total_amount_paid_msat += path.last().unwrap().fee_msat;
4620 assert_eq!(total_amount_paid_msat, 90_000);
4625 fn min_criteria_consistency() {
4626 // Test that we don't use an inconsistent metric between updating and walking nodes during
4627 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4628 // was updated with a different criterion from the heap sorting, resulting in loops in
4629 // calculated paths. We test for that specific case here.
4631 // We construct a network that looks like this:
4633 // node2 -1(3)2- node3
4637 // node1 -1(5)2- node4 -1(1)2- node6
4643 // We create a loop on the side of our real path - our destination is node 6, with a
4644 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4645 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4646 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4647 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4648 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4649 // "previous hop" being set to node 3, creating a loop in the path.
4650 let secp_ctx = Secp256k1::new();
4651 let logger = Arc::new(test_utils::TestLogger::new());
4652 let network = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
4653 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network), None, Arc::clone(&logger));
4654 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4655 let scorer = test_utils::TestScorer::with_penalty(0);
4656 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4657 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4658 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4660 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4661 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4662 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4663 short_channel_id: 6,
4666 cltv_expiry_delta: (6 << 4) | 0,
4667 htlc_minimum_msat: 0,
4668 htlc_maximum_msat: OptionalField::Absent,
4670 fee_proportional_millionths: 0,
4671 excess_data: Vec::new()
4673 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4675 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4676 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4677 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4678 short_channel_id: 5,
4681 cltv_expiry_delta: (5 << 4) | 0,
4682 htlc_minimum_msat: 0,
4683 htlc_maximum_msat: OptionalField::Absent,
4685 fee_proportional_millionths: 0,
4686 excess_data: Vec::new()
4688 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4690 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4691 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4692 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4693 short_channel_id: 4,
4696 cltv_expiry_delta: (4 << 4) | 0,
4697 htlc_minimum_msat: 0,
4698 htlc_maximum_msat: OptionalField::Absent,
4700 fee_proportional_millionths: 0,
4701 excess_data: Vec::new()
4703 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4705 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4706 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4707 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4708 short_channel_id: 3,
4711 cltv_expiry_delta: (3 << 4) | 0,
4712 htlc_minimum_msat: 0,
4713 htlc_maximum_msat: OptionalField::Absent,
4715 fee_proportional_millionths: 0,
4716 excess_data: Vec::new()
4718 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4720 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4721 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4722 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4723 short_channel_id: 2,
4726 cltv_expiry_delta: (2 << 4) | 0,
4727 htlc_minimum_msat: 0,
4728 htlc_maximum_msat: OptionalField::Absent,
4730 fee_proportional_millionths: 0,
4731 excess_data: Vec::new()
4734 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4735 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4736 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4737 short_channel_id: 1,
4740 cltv_expiry_delta: (1 << 4) | 0,
4741 htlc_minimum_msat: 100,
4742 htlc_maximum_msat: OptionalField::Absent,
4744 fee_proportional_millionths: 0,
4745 excess_data: Vec::new()
4747 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4750 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4751 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4752 assert_eq!(route.paths.len(), 1);
4753 assert_eq!(route.paths[0].len(), 3);
4755 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4756 assert_eq!(route.paths[0][0].short_channel_id, 6);
4757 assert_eq!(route.paths[0][0].fee_msat, 100);
4758 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4759 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4760 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4762 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4763 assert_eq!(route.paths[0][1].short_channel_id, 5);
4764 assert_eq!(route.paths[0][1].fee_msat, 0);
4765 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4766 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4767 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4769 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4770 assert_eq!(route.paths[0][2].short_channel_id, 1);
4771 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4772 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4773 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4774 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4780 fn exact_fee_liquidity_limit() {
4781 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4782 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4783 // we calculated fees on a higher value, resulting in us ignoring such paths.
4784 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4785 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4786 let scorer = test_utils::TestScorer::with_penalty(0);
4787 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4788 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4789 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4791 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4793 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4794 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4795 short_channel_id: 2,
4798 cltv_expiry_delta: 0,
4799 htlc_minimum_msat: 0,
4800 htlc_maximum_msat: OptionalField::Present(85_000),
4802 fee_proportional_millionths: 0,
4803 excess_data: Vec::new()
4806 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4807 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4808 short_channel_id: 12,
4811 cltv_expiry_delta: (4 << 4) | 1,
4812 htlc_minimum_msat: 0,
4813 htlc_maximum_msat: OptionalField::Present(270_000),
4815 fee_proportional_millionths: 1000000,
4816 excess_data: Vec::new()
4820 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4821 // 200% fee charged channel 13 in the 1-to-2 direction.
4822 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4823 assert_eq!(route.paths.len(), 1);
4824 assert_eq!(route.paths[0].len(), 2);
4826 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4827 assert_eq!(route.paths[0][0].short_channel_id, 12);
4828 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4829 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4830 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4831 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4833 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4834 assert_eq!(route.paths[0][1].short_channel_id, 13);
4835 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4836 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4837 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4838 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4843 fn htlc_max_reduction_below_min() {
4844 // Test that if, while walking the graph, we reduce the value being sent to meet an
4845 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4846 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4847 // resulting in us thinking there is no possible path, even if other paths exist.
4848 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4849 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4850 let scorer = test_utils::TestScorer::with_penalty(0);
4851 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4852 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4853 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4855 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4856 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4857 // then try to send 90_000.
4858 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4860 short_channel_id: 2,
4863 cltv_expiry_delta: 0,
4864 htlc_minimum_msat: 0,
4865 htlc_maximum_msat: OptionalField::Present(80_000),
4867 fee_proportional_millionths: 0,
4868 excess_data: Vec::new()
4870 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4871 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4872 short_channel_id: 4,
4875 cltv_expiry_delta: (4 << 4) | 1,
4876 htlc_minimum_msat: 90_000,
4877 htlc_maximum_msat: OptionalField::Absent,
4879 fee_proportional_millionths: 0,
4880 excess_data: Vec::new()
4884 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4885 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4886 // expensive) channels 12-13 path.
4887 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4888 assert_eq!(route.paths.len(), 1);
4889 assert_eq!(route.paths[0].len(), 2);
4891 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4892 assert_eq!(route.paths[0][0].short_channel_id, 12);
4893 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4894 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4895 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4896 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4898 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4899 assert_eq!(route.paths[0][1].short_channel_id, 13);
4900 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4901 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4902 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
4903 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4908 fn multiple_direct_first_hops() {
4909 // Previously we'd only ever considered one first hop path per counterparty.
4910 // However, as we don't restrict users to one channel per peer, we really need to support
4911 // looking at all first hop paths.
4912 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4913 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4914 // route over multiple channels with the same first hop.
4915 let secp_ctx = Secp256k1::new();
4916 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4917 let logger = Arc::new(test_utils::TestLogger::new());
4918 let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
4919 let scorer = test_utils::TestScorer::with_penalty(0);
4920 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
4921 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4922 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4925 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4926 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
4927 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
4928 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4929 assert_eq!(route.paths.len(), 1);
4930 assert_eq!(route.paths[0].len(), 1);
4932 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4933 assert_eq!(route.paths[0][0].short_channel_id, 3);
4934 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4937 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4938 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4939 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4940 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4941 assert_eq!(route.paths.len(), 2);
4942 assert_eq!(route.paths[0].len(), 1);
4943 assert_eq!(route.paths[1].len(), 1);
4945 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4946 assert_eq!(route.paths[0][0].short_channel_id, 3);
4947 assert_eq!(route.paths[0][0].fee_msat, 50_000);
4949 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
4950 assert_eq!(route.paths[1][0].short_channel_id, 2);
4951 assert_eq!(route.paths[1][0].fee_msat, 50_000);
4955 // If we have a bunch of outbound channels to the same node, where most are not
4956 // sufficient to pay the full payment, but one is, we should default to just using the
4957 // one single channel that has sufficient balance, avoiding MPP.
4959 // If we have several options above the 3xpayment value threshold, we should pick the
4960 // smallest of them, avoiding further fragmenting our available outbound balance to
4962 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4963 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4964 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4965 &get_channel_details(Some(5), nodes[0], InitFeatures::known(), 50_000),
4966 &get_channel_details(Some(6), nodes[0], InitFeatures::known(), 300_000),
4967 &get_channel_details(Some(7), nodes[0], InitFeatures::known(), 50_000),
4968 &get_channel_details(Some(8), nodes[0], InitFeatures::known(), 50_000),
4969 &get_channel_details(Some(9), nodes[0], InitFeatures::known(), 50_000),
4970 &get_channel_details(Some(4), nodes[0], InitFeatures::known(), 1_000_000),
4971 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4972 assert_eq!(route.paths.len(), 1);
4973 assert_eq!(route.paths[0].len(), 1);
4975 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4976 assert_eq!(route.paths[0][0].short_channel_id, 6);
4977 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4982 fn prefers_shorter_route_with_higher_fees() {
4983 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4984 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4985 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4987 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
4988 let scorer = test_utils::TestScorer::with_penalty(0);
4989 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4990 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4991 let route = get_route(
4992 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
4993 Arc::clone(&logger), &scorer, &random_seed_bytes
4995 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4997 assert_eq!(route.get_total_fees(), 100);
4998 assert_eq!(route.get_total_amount(), 100);
4999 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5001 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5002 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5003 let scorer = test_utils::TestScorer::with_penalty(100);
5004 let route = get_route(
5005 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5006 Arc::clone(&logger), &scorer, &random_seed_bytes
5008 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5010 assert_eq!(route.get_total_fees(), 300);
5011 assert_eq!(route.get_total_amount(), 100);
5012 assert_eq!(path, vec![2, 4, 7, 10]);
5015 struct BadChannelScorer {
5016 short_channel_id: u64,
5020 impl Writeable for BadChannelScorer {
5021 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5023 impl Score for BadChannelScorer {
5024 fn channel_penalty_msat(&self, short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId) -> u64 {
5025 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5028 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5029 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5032 struct BadNodeScorer {
5037 impl Writeable for BadNodeScorer {
5038 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5041 impl Score for BadNodeScorer {
5042 fn channel_penalty_msat(&self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, target: &NodeId) -> u64 {
5043 if *target == self.node_id { u64::max_value() } else { 0 }
5046 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5047 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5051 fn avoids_routing_through_bad_channels_and_nodes() {
5052 let (secp_ctx, network, _, _, logger) = build_graph();
5053 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5054 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5055 let network_graph = network.read_only();
5057 // A path to nodes[6] exists when no penalties are applied to any channel.
5058 let scorer = test_utils::TestScorer::with_penalty(0);
5059 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5060 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5061 let route = get_route(
5062 &our_id, &payment_params, &network_graph, None, 100, 42,
5063 Arc::clone(&logger), &scorer, &random_seed_bytes
5065 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5067 assert_eq!(route.get_total_fees(), 100);
5068 assert_eq!(route.get_total_amount(), 100);
5069 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5071 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5072 let scorer = BadChannelScorer { short_channel_id: 6 };
5073 let route = get_route(
5074 &our_id, &payment_params, &network_graph, None, 100, 42,
5075 Arc::clone(&logger), &scorer, &random_seed_bytes
5077 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5079 assert_eq!(route.get_total_fees(), 300);
5080 assert_eq!(route.get_total_amount(), 100);
5081 assert_eq!(path, vec![2, 4, 7, 10]);
5083 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5084 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5086 &our_id, &payment_params, &network_graph, None, 100, 42,
5087 Arc::clone(&logger), &scorer, &random_seed_bytes
5089 Err(LightningError { err, .. } ) => {
5090 assert_eq!(err, "Failed to find a path to the given destination");
5092 Ok(_) => panic!("Expected error"),
5097 fn total_fees_single_path() {
5101 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5102 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5103 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5106 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5107 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5108 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5111 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5112 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5113 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5116 payment_params: None,
5119 assert_eq!(route.get_total_fees(), 250);
5120 assert_eq!(route.get_total_amount(), 225);
5124 fn total_fees_multi_path() {
5128 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5129 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5130 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5133 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5134 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5135 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5139 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5140 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5141 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5144 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5145 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5146 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5149 payment_params: None,
5152 assert_eq!(route.get_total_fees(), 200);
5153 assert_eq!(route.get_total_amount(), 300);
5157 fn total_empty_route_no_panic() {
5158 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5159 // would both panic if the route was completely empty. We test to ensure they return 0
5160 // here, even though its somewhat nonsensical as a route.
5161 let route = Route { paths: Vec::new(), payment_params: None };
5163 assert_eq!(route.get_total_fees(), 0);
5164 assert_eq!(route.get_total_amount(), 0);
5168 fn limits_total_cltv_delta() {
5169 let (secp_ctx, network, _, _, logger) = build_graph();
5170 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5171 let network_graph = network.read_only();
5173 let scorer = test_utils::TestScorer::with_penalty(0);
5175 // Make sure that generally there is at least one route available
5176 let feasible_max_total_cltv_delta = 1008;
5177 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5178 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5179 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5180 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5181 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5182 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5183 assert_ne!(path.len(), 0);
5185 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5186 let fail_max_total_cltv_delta = 23;
5187 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5188 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5189 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5191 Err(LightningError { err, .. } ) => {
5192 assert_eq!(err, "Failed to find a path to the given destination");
5194 Ok(_) => panic!("Expected error"),
5199 fn adds_and_limits_cltv_offset() {
5200 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5201 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5203 let scorer = test_utils::TestScorer::with_penalty(0);
5205 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5206 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5207 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5208 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5209 assert_eq!(route.paths.len(), 1);
5211 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5213 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5214 let mut route_default = route.clone();
5215 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5216 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5217 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5218 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5219 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5221 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5222 let mut route_limited = route.clone();
5223 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5224 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5225 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5226 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5227 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5231 fn adds_plausible_cltv_offset() {
5232 let (secp_ctx, network, _, _, logger) = build_graph();
5233 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5234 let network_graph = network.read_only();
5235 let network_nodes = network_graph.nodes();
5236 let network_channels = network_graph.channels();
5237 let scorer = test_utils::TestScorer::with_penalty(0);
5238 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5239 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5240 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5242 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5243 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5244 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5246 let mut path_plausibility = vec![];
5248 for p in route.paths {
5249 // 1. Select random observation point
5250 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5251 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5253 prng.process_in_place(&mut random_bytes);
5254 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5255 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5257 // 2. Calculate what CLTV expiry delta we would observe there
5258 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5260 // 3. Starting from the observation point, find candidate paths
5261 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5262 candidates.push_back((observation_point, vec![]));
5264 let mut found_plausible_candidate = false;
5266 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5267 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5268 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5269 found_plausible_candidate = true;
5270 break 'candidate_loop;
5274 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5275 for channel_id in &cur_node.channels {
5276 if let Some(channel_info) = network_channels.get(&channel_id) {
5277 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5278 if let Some(channel_update_info) = dir_info.direction() {
5279 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5280 if cur_path_cltv_deltas.iter().sum::<u32>()
5281 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5282 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5283 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5284 candidates.push_back((*next_id, new_path_cltv_deltas));
5293 path_plausibility.push(found_plausible_candidate);
5295 assert!(path_plausibility.iter().all(|x| *x));
5298 #[cfg(not(feature = "no-std"))]
5299 pub(super) fn random_init_seed() -> u64 {
5300 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5301 use core::hash::{BuildHasher, Hasher};
5302 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5303 println!("Using seed of {}", seed);
5306 #[cfg(not(feature = "no-std"))]
5307 use util::ser::Readable;
5310 #[cfg(not(feature = "no-std"))]
5311 fn generate_routes() {
5312 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5314 let mut d = match super::test_utils::get_route_file() {
5321 let graph = NetworkGraph::read(&mut d).unwrap();
5322 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5323 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5325 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5326 let mut seed = random_init_seed() as usize;
5327 let nodes = graph.read_only().nodes().clone();
5328 'load_endpoints: for _ in 0..10 {
5330 seed = seed.overflowing_mul(0xdeadbeef).0;
5331 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5332 seed = seed.overflowing_mul(0xdeadbeef).0;
5333 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5334 let payment_params = PaymentParameters::from_node_id(dst);
5335 let amt = seed as u64 % 200_000_000;
5336 let params = ProbabilisticScoringParameters::default();
5337 let scorer = ProbabilisticScorer::new(params, &graph);
5338 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5339 continue 'load_endpoints;
5346 #[cfg(not(feature = "no-std"))]
5347 fn generate_routes_mpp() {
5348 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5350 let mut d = match super::test_utils::get_route_file() {
5357 let graph = NetworkGraph::read(&mut d).unwrap();
5358 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5359 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5361 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5362 let mut seed = random_init_seed() as usize;
5363 let nodes = graph.read_only().nodes().clone();
5364 'load_endpoints: for _ in 0..10 {
5366 seed = seed.overflowing_mul(0xdeadbeef).0;
5367 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5368 seed = seed.overflowing_mul(0xdeadbeef).0;
5369 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5370 let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
5371 let amt = seed as u64 % 200_000_000;
5372 let params = ProbabilisticScoringParameters::default();
5373 let scorer = ProbabilisticScorer::new(params, &graph);
5374 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5375 continue 'load_endpoints;
5382 #[cfg(all(test, not(feature = "no-std")))]
5383 pub(crate) mod test_utils {
5385 /// Tries to open a network graph file, or panics with a URL to fetch it.
5386 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5387 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5388 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5389 .or_else(|_| { // Fall back to guessing based on the binary location
5390 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5391 let mut path = std::env::current_exe().unwrap();
5392 path.pop(); // lightning-...
5394 path.pop(); // debug
5395 path.pop(); // target
5396 path.push("lightning");
5397 path.push("net_graph-2021-05-31.bin");
5398 eprintln!("{}", path.to_str().unwrap());
5401 .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");
5402 #[cfg(require_route_graph_test)]
5403 return Ok(res.unwrap());
5404 #[cfg(not(require_route_graph_test))]
5409 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5412 use bitcoin::hashes::Hash;
5413 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5414 use chain::transaction::OutPoint;
5415 use chain::keysinterface::{KeysManager,KeysInterface};
5416 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
5417 use ln::features::{InitFeatures, InvoiceFeatures};
5418 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters, Scorer};
5419 use util::logger::{Logger, Record};
5423 struct DummyLogger {}
5424 impl Logger for DummyLogger {
5425 fn log(&self, _record: &Record) {}
5428 fn read_network_graph() -> NetworkGraph {
5429 let mut d = test_utils::get_route_file().unwrap();
5430 NetworkGraph::read(&mut d).unwrap()
5433 fn payer_pubkey() -> PublicKey {
5434 let secp_ctx = Secp256k1::new();
5435 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5439 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5441 channel_id: [0; 32],
5442 counterparty: ChannelCounterparty {
5443 features: InitFeatures::known(),
5445 unspendable_punishment_reserve: 0,
5446 forwarding_info: None,
5448 funding_txo: Some(OutPoint {
5449 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5452 short_channel_id: Some(1),
5453 inbound_scid_alias: None,
5454 channel_value_satoshis: 10_000_000,
5456 balance_msat: 10_000_000,
5457 outbound_capacity_msat: 10_000_000,
5458 inbound_capacity_msat: 0,
5459 unspendable_punishment_reserve: None,
5460 confirmations_required: None,
5461 force_close_spend_delay: None,
5463 is_funding_locked: true,
5470 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5471 let network_graph = read_network_graph();
5472 let scorer = FixedPenaltyScorer::with_penalty(0);
5473 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5477 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5478 let network_graph = read_network_graph();
5479 let scorer = FixedPenaltyScorer::with_penalty(0);
5480 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5484 fn generate_routes_with_default_scorer(bench: &mut Bencher) {
5485 let network_graph = read_network_graph();
5486 let scorer = Scorer::default();
5487 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5491 fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
5492 let network_graph = read_network_graph();
5493 let scorer = Scorer::default();
5494 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5498 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5499 let network_graph = read_network_graph();
5500 let params = ProbabilisticScoringParameters::default();
5501 let scorer = ProbabilisticScorer::new(params, &network_graph);
5502 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5506 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5507 let network_graph = read_network_graph();
5508 let params = ProbabilisticScoringParameters::default();
5509 let scorer = ProbabilisticScorer::new(params, &network_graph);
5510 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5513 fn generate_routes<S: Score>(
5514 bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
5516 let nodes = graph.read_only().nodes().clone();
5517 let payer = payer_pubkey();
5518 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5519 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5521 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5522 let mut routes = Vec::new();
5523 let mut route_endpoints = Vec::new();
5524 let mut seed: usize = 0xdeadbeef;
5525 'load_endpoints: for _ in 0..150 {
5528 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5530 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5531 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5532 let first_hop = first_hop(src);
5533 let amt = seed as u64 % 1_000_000;
5534 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5536 route_endpoints.push((first_hop, params, amt));
5537 continue 'load_endpoints;
5542 // ...and seed the scorer with success and failure data...
5543 for route in routes {
5544 let amount = route.get_total_amount();
5545 if amount < 250_000 {
5546 for path in route.paths {
5547 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5549 } else if amount > 750_000 {
5550 for path in route.paths {
5551 let short_channel_id = path[path.len() / 2].short_channel_id;
5552 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5557 // Because we've changed channel scores, its possible we'll take different routes to the
5558 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5559 // requires a too-high CLTV delta.
5560 route_endpoints.retain(|(first_hop, params, amt)| {
5561 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5563 route_endpoints.truncate(100);
5564 assert_eq!(route_endpoints.len(), 100);
5566 // ...then benchmark finding paths between the nodes we learned.
5569 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5570 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());