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::{DirectedChannelInfo, EffectiveCapacity, NetworkGraph, NodeId, RoutingFees};
22 use util::ser::{Writeable, Readable};
23 use util::logger::{Level, Logger};
27 use alloc::collections::BinaryHeap;
32 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
34 /// The node_id of the node at this hop.
35 pub pubkey: PublicKey,
36 /// The node_announcement features of the node at this hop. For the last hop, these may be
37 /// amended to match the features present in the invoice this node generated.
38 pub node_features: NodeFeatures,
39 /// The channel that should be used from the previous hop to reach this node.
40 pub short_channel_id: u64,
41 /// The channel_announcement features of the channel that should be used from the previous hop
42 /// to reach this node.
43 pub channel_features: ChannelFeatures,
44 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
45 /// For the last hop, this should be the full value of the payment (might be more than
46 /// requested if we had to match htlc_minimum_msat).
48 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
49 /// expected at the destination, in excess of the current block height.
50 pub cltv_expiry_delta: u32,
53 impl_writeable_tlv_based!(RouteHop, {
54 (0, pubkey, required),
55 (2, node_features, required),
56 (4, short_channel_id, required),
57 (6, channel_features, required),
58 (8, fee_msat, required),
59 (10, cltv_expiry_delta, required),
62 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
63 /// it can take multiple paths. Each path is composed of one or more hops through the network.
64 #[derive(Clone, Hash, PartialEq, Eq)]
66 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
67 /// last RouteHop in each path must be the same.
68 /// Each entry represents a list of hops, NOT INCLUDING our own, where the last hop is the
69 /// destination. Thus, this must always be at least length one. While the maximum length of any
70 /// given path is variable, keeping the length of any path to less than 20 should currently
71 /// ensure it is viable.
72 pub paths: Vec<Vec<RouteHop>>,
73 /// The `payee` parameter passed to [`find_route`].
74 /// This is used by `ChannelManager` to track information which may be required for retries,
75 /// provided back to you via [`Event::PaymentPathFailed`].
77 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
78 pub payee: Option<Payee>,
81 pub(crate) trait RoutePath {
82 /// Gets the fees for a given path, excluding any excess paid to the recipient.
83 fn get_path_fees(&self) -> u64;
85 impl RoutePath for Vec<RouteHop> {
86 fn get_path_fees(&self) -> u64 {
87 // Do not count last hop of each path since that's the full value of the payment
88 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
89 .iter().map(|hop| &hop.fee_msat)
95 /// Returns the total amount of fees paid on this [`Route`].
97 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
98 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
99 pub fn get_total_fees(&self) -> u64 {
100 self.paths.iter().map(|path| path.get_path_fees()).sum()
103 /// Returns the total amount paid on this [`Route`], excluding the fees.
104 pub fn get_total_amount(&self) -> u64 {
105 return self.paths.iter()
106 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
111 const SERIALIZATION_VERSION: u8 = 1;
112 const MIN_SERIALIZATION_VERSION: u8 = 1;
114 impl Writeable for Route {
115 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
116 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
117 (self.paths.len() as u64).write(writer)?;
118 for hops in self.paths.iter() {
119 (hops.len() as u8).write(writer)?;
120 for hop in hops.iter() {
124 write_tlv_fields!(writer, {
125 (1, self.payee, option),
131 impl Readable for Route {
132 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
133 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
134 let path_count: u64 = Readable::read(reader)?;
135 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
136 for _ in 0..path_count {
137 let hop_count: u8 = Readable::read(reader)?;
138 let mut hops = Vec::with_capacity(hop_count as usize);
139 for _ in 0..hop_count {
140 hops.push(Readable::read(reader)?);
144 let mut payee = None;
145 read_tlv_fields!(reader, {
148 Ok(Route { paths, payee })
152 /// Parameters needed to find a [`Route`] for paying a [`Payee`].
154 /// Passed to [`find_route`] and also provided in [`Event::PaymentPathFailed`] for retrying a failed
157 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
158 #[derive(Clone, Debug)]
159 pub struct RouteParameters {
160 /// The recipient of the failed payment path.
163 /// The amount in msats sent on the failed payment path.
164 pub final_value_msat: u64,
166 /// The CLTV on the final hop of the failed payment path.
167 pub final_cltv_expiry_delta: u32,
170 impl_writeable_tlv_based!(RouteParameters, {
171 (0, payee, required),
172 (2, final_value_msat, required),
173 (4, final_cltv_expiry_delta, required),
176 /// Maximum total CTLV difference we allow for a full payment path.
177 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
179 /// The recipient of a payment.
180 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
182 /// The node id of the payee.
183 pub pubkey: PublicKey,
185 /// Features supported by the payee.
187 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
188 /// does not contain any features.
190 /// [`for_keysend`]: Self::for_keysend
191 pub features: Option<InvoiceFeatures>,
193 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
194 pub route_hints: Vec<RouteHint>,
196 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
197 pub expiry_time: Option<u64>,
199 /// The maximum total CLTV delta we accept for the route.
200 pub max_total_cltv_expiry_delta: u32,
203 impl_writeable_tlv_based!(Payee, {
204 (0, pubkey, required),
205 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
206 (2, features, option),
207 (4, route_hints, vec_type),
208 (6, expiry_time, option),
212 /// Creates a payee with the node id of the given `pubkey`.
213 pub fn from_node_id(pubkey: PublicKey) -> Self {
219 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
223 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
224 pub fn for_keysend(pubkey: PublicKey) -> Self {
225 Self::from_node_id(pubkey).with_features(InvoiceFeatures::for_keysend())
228 /// Includes the payee's features.
230 /// (C-not exported) since bindings don't support move semantics
231 pub fn with_features(self, features: InvoiceFeatures) -> Self {
232 Self { features: Some(features), ..self }
235 /// Includes hints for routing to the payee.
237 /// (C-not exported) since bindings don't support move semantics
238 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
239 Self { route_hints, ..self }
242 /// Includes a payment expiration in seconds relative to the UNIX epoch.
244 /// (C-not exported) since bindings don't support move semantics
245 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
246 Self { expiry_time: Some(expiry_time), ..self }
249 /// Includes a limit for the total CLTV expiry delta which is considered during routing
251 /// (C-not exported) since bindings don't support move semantics
252 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
253 Self { max_total_cltv_expiry_delta, ..self }
257 /// A list of hops along a payment path terminating with a channel to the recipient.
258 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
259 pub struct RouteHint(pub Vec<RouteHintHop>);
262 impl Writeable for RouteHint {
263 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
264 (self.0.len() as u64).write(writer)?;
265 for hop in self.0.iter() {
272 impl Readable for RouteHint {
273 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
274 let hop_count: u64 = Readable::read(reader)?;
275 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
276 for _ in 0..hop_count {
277 hops.push(Readable::read(reader)?);
283 /// A channel descriptor for a hop along a payment path.
284 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
285 pub struct RouteHintHop {
286 /// The node_id of the non-target end of the route
287 pub src_node_id: PublicKey,
288 /// The short_channel_id of this channel
289 pub short_channel_id: u64,
290 /// The fees which must be paid to use this channel
291 pub fees: RoutingFees,
292 /// The difference in CLTV values between this node and the next node.
293 pub cltv_expiry_delta: u16,
294 /// The minimum value, in msat, which must be relayed to the next hop.
295 pub htlc_minimum_msat: Option<u64>,
296 /// The maximum value in msat available for routing with a single HTLC.
297 pub htlc_maximum_msat: Option<u64>,
300 impl_writeable_tlv_based!(RouteHintHop, {
301 (0, src_node_id, required),
302 (1, htlc_minimum_msat, option),
303 (2, short_channel_id, required),
304 (3, htlc_maximum_msat, option),
306 (6, cltv_expiry_delta, required),
309 #[derive(Eq, PartialEq)]
310 struct RouteGraphNode {
312 lowest_fee_to_peer_through_node: u64,
313 lowest_fee_to_node: u64,
314 total_cltv_delta: u32,
315 // The maximum value a yet-to-be-constructed payment path might flow through this node.
316 // This value is upper-bounded by us by:
317 // - how much is needed for a path being constructed
318 // - how much value can channels following this node (up to the destination) can contribute,
319 // considering their capacity and fees
320 value_contribution_msat: u64,
321 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
322 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
323 path_htlc_minimum_msat: u64,
324 /// All penalties incurred from this hop on the way to the destination, as calculated using
326 path_penalty_msat: u64,
329 impl cmp::Ord for RouteGraphNode {
330 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
331 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
332 .checked_add(other.path_penalty_msat)
333 .unwrap_or_else(|| u64::max_value());
334 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
335 .checked_add(self.path_penalty_msat)
336 .unwrap_or_else(|| u64::max_value());
337 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
341 impl cmp::PartialOrd for RouteGraphNode {
342 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
343 Some(self.cmp(other))
347 /// A wrapper around the various hop representations.
349 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
350 #[derive(Clone, Debug)]
351 enum CandidateRouteHop<'a> {
352 /// A hop from the payer to the next hop to the payee, where the outbound liquidity is known.
354 details: &'a ChannelDetails,
356 /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
358 // `DirectedChannelInfo::direction` MUST NOT be `None`.
359 info: DirectedChannelInfo<'a, '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 fn features(&self) -> ChannelFeatures {
379 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
380 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
381 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
385 fn cltv_expiry_delta(&self) -> u32 {
387 CandidateRouteHop::FirstHop { .. } => 0,
388 CandidateRouteHop::PublicHop { info, .. } => {
389 info.direction().unwrap().cltv_expiry_delta as u32
391 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
395 fn htlc_minimum_msat(&self) -> u64 {
397 CandidateRouteHop::FirstHop { .. } => 0,
398 CandidateRouteHop::PublicHop { info, .. } => {
399 info.direction().unwrap().htlc_minimum_msat
401 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
405 fn fees(&self) -> RoutingFees {
407 CandidateRouteHop::FirstHop { .. } => RoutingFees {
408 base_msat: 0, proportional_millionths: 0,
410 CandidateRouteHop::PublicHop { info, .. } => info.direction().unwrap().fees,
411 CandidateRouteHop::PrivateHop { hint } => hint.fees,
415 fn effective_capacity(&self) -> EffectiveCapacity {
417 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
418 liquidity_msat: details.outbound_capacity_msat,
420 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
421 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
426 /// It's useful to keep track of the hops associated with the fees required to use them,
427 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
428 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
429 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
430 #[derive(Clone, Debug)]
431 struct PathBuildingHop<'a> {
432 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
433 // is a larger refactor and will require careful performance analysis.
435 candidate: CandidateRouteHop<'a>,
438 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
439 src_lowest_inbound_fees: RoutingFees,
440 /// All the fees paid *after* this channel on the way to the destination
441 next_hops_fee_msat: u64,
442 /// Fee paid for the use of the current channel (see candidate.fees()).
443 /// The value will be actually deducted from the counterparty balance on the previous link.
444 hop_use_fee_msat: u64,
445 /// Used to compare channels when choosing the for routing.
446 /// Includes paying for the use of a hop and the following hops, as well as
447 /// an estimated cost of reaching this hop.
448 /// Might get stale when fees are recomputed. Primarily for internal use.
450 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
451 /// walk and may be invalid thereafter.
452 path_htlc_minimum_msat: u64,
453 /// All penalties incurred from this channel on the way to the destination, as calculated using
455 path_penalty_msat: u64,
456 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
457 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
458 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
459 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
460 /// avoid processing them again.
462 #[cfg(any(test, feature = "fuzztarget"))]
463 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
464 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
465 // value_contribution_msat, which requires tracking it here. See comments below where it is
466 // used for more info.
467 value_contribution_msat: u64,
470 // Instantiated with a list of hops with correct data in them collected during path finding,
471 // an instance of this struct should be further modified only via given methods.
473 struct PaymentPath<'a> {
474 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
477 impl<'a> PaymentPath<'a> {
478 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
479 fn get_value_msat(&self) -> u64 {
480 self.hops.last().unwrap().0.fee_msat
483 fn get_total_fee_paid_msat(&self) -> u64 {
484 if self.hops.len() < 1 {
488 // Can't use next_hops_fee_msat because it gets outdated.
489 for (i, (hop, _)) in self.hops.iter().enumerate() {
490 if i != self.hops.len() - 1 {
491 result += hop.fee_msat;
497 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
498 // to change fees may result in an inconsistency.
500 // Sometimes we call this function right after constructing a path which is inconsistent in
501 // that it the value being transferred has decreased while we were doing path finding, leading
502 // to the fees being paid not lining up with the actual limits.
504 // Note that this function is not aware of the available_liquidity limit, and thus does not
505 // support increasing the value being transferred.
506 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
507 assert!(value_msat <= self.hops.last().unwrap().0.fee_msat);
509 let mut total_fee_paid_msat = 0 as u64;
510 for i in (0..self.hops.len()).rev() {
511 let last_hop = i == self.hops.len() - 1;
513 // For non-last-hop, this value will represent the fees paid on the current hop. It
514 // will consist of the fees for the use of the next hop, and extra fees to match
515 // htlc_minimum_msat of the current channel. Last hop is handled separately.
516 let mut cur_hop_fees_msat = 0;
518 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
521 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
522 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
523 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
524 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
525 // set it too high just to maliciously take more fees by exploiting this
526 // match htlc_minimum_msat logic.
527 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
528 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
529 // Note that there is a risk that *previous hops* (those closer to us, as we go
530 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
532 // This might make us end up with a broken route, although this should be super-rare
533 // in practice, both because of how healthy channels look like, and how we pick
534 // channels in add_entry.
535 // Also, this can't be exploited more heavily than *announce a free path and fail
537 cur_hop_transferred_amount_msat += extra_fees_msat;
538 total_fee_paid_msat += extra_fees_msat;
539 cur_hop_fees_msat += extra_fees_msat;
543 // Final hop is a special case: it usually has just value_msat (by design), but also
544 // it still could overpay for the htlc_minimum_msat.
545 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
547 // Propagate updated fees for the use of the channels to one hop back, where they
548 // will be actually paid (fee_msat). The last hop is handled above separately.
549 cur_hop.fee_msat = cur_hop_fees_msat;
552 // Fee for the use of the current hop which will be deducted on the previous hop.
553 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
554 // this channel is free for us.
556 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
557 cur_hop.hop_use_fee_msat = new_fee;
558 total_fee_paid_msat += new_fee;
560 // It should not be possible because this function is called only to reduce the
561 // value. In that case, compute_fee was already called with the same fees for
562 // larger amount and there was no overflow.
570 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
571 let proportional_fee_millions =
572 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
573 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
574 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
578 // This function may be (indirectly) called without any verification,
579 // with channel_fees provided by a caller. We should handle it gracefully.
584 /// Finds a route from us (payer) to the given target node (payee).
586 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
587 /// Without this, MPP will only be used if the payee's features are available in the network graph.
589 /// Private routing paths between a public node and the target may be included in `params.payee`.
591 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
592 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
593 /// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
595 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
596 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
597 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
601 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
602 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
607 /// Panics if first_hops contains channels without short_channel_ids;
608 /// [`ChannelManager::list_usable_channels`] will never include such channels.
610 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
611 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
612 pub fn find_route<L: Deref, S: Score>(
613 our_node_pubkey: &PublicKey, params: &RouteParameters, network: &NetworkGraph,
614 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S
615 ) -> Result<Route, LightningError>
616 where L::Target: Logger {
618 our_node_pubkey, ¶ms.payee, network, first_hops, params.final_value_msat,
619 params.final_cltv_expiry_delta, logger, scorer
623 pub(crate) fn get_route<L: Deref, S: Score>(
624 our_node_pubkey: &PublicKey, payee: &Payee, network: &NetworkGraph,
625 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
626 logger: L, scorer: &S
627 ) -> Result<Route, LightningError>
628 where L::Target: Logger {
629 let payee_node_id = NodeId::from_pubkey(&payee.pubkey);
630 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
632 if payee_node_id == our_node_id {
633 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
636 if final_value_msat > MAX_VALUE_MSAT {
637 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
640 if final_value_msat == 0 {
641 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
644 for route in payee.route_hints.iter() {
645 for hop in &route.0 {
646 if hop.src_node_id == payee.pubkey {
647 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
652 // The general routing idea is the following:
653 // 1. Fill first/last hops communicated by the caller.
654 // 2. Attempt to construct a path from payer to payee for transferring
655 // any ~sufficient (described later) value.
656 // If succeed, remember which channels were used and how much liquidity they have available,
657 // so that future paths don't rely on the same liquidity.
658 // 3. Proceed to the next step if:
659 // - we hit the recommended target value;
660 // - OR if we could not construct a new path. Any next attempt will fail too.
661 // Otherwise, repeat step 2.
662 // 4. See if we managed to collect paths which aggregately are able to transfer target value
663 // (not recommended value). If yes, proceed. If not, fail routing.
664 // 5. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
665 // 6. Of all the found paths, select only those with the lowest total fee.
666 // 7. The last path in every selected route is likely to be more than we need.
667 // Reduce its value-to-transfer and recompute fees.
668 // 8. Choose the best route by the lowest total fee.
670 // As for the actual search algorithm,
671 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
672 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
674 // We are not a faithful Dijkstra's implementation because we can change values which impact
675 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
676 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
677 // the value we are currently attempting to send over a path, we simply reduce the value being
678 // sent along the path for any hops after that channel. This may imply that later fees (which
679 // we've already tabulated) are lower because a smaller value is passing through the channels
680 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
681 // channels which were selected earlier (and which may still be used for other paths without a
682 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
685 // One potentially problematic case for this algorithm would be if there are many
686 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
687 // graph walking), we may never find a path which is not liquidity-limited and has lower
688 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
689 // Because we only consider paths with at least 5% of the total value being sent, the damage
690 // from such a case should be limited, however this could be further reduced in the future by
691 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
692 // limits for the purposes of fee calculation.
694 // Alternatively, we could store more detailed path information in the heap (targets, below)
695 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
696 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
697 // and practically (as we would need to store dynamically-allocated path information in heap
698 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
699 // results of such an algorithm would likely be biased towards lower-value paths.
701 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
702 // outside of our current search value, running a path search more times to gather candidate
703 // paths at different values. While this may be acceptable, further path searches may increase
704 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
705 // graph for candidate paths, calculating the maximum value which can realistically be sent at
706 // the same time, remaining generic across different payment values.
708 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
709 // to use as the A* heuristic beyond just the cost to get one node further than the current
712 let network_graph = network.read_only();
713 let network_channels = network_graph.channels();
714 let network_nodes = network_graph.nodes();
716 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
717 // it. If the payee supports it they're supposed to include it in the invoice, so that should
719 let allow_mpp = if let Some(features) = &payee.features {
720 features.supports_basic_mpp()
721 } else if let Some(node) = network_nodes.get(&payee_node_id) {
722 if let Some(node_info) = node.announcement_info.as_ref() {
723 node_info.features.supports_basic_mpp()
726 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP", our_node_pubkey,
727 payee.pubkey, if allow_mpp { "with" } else { "without" });
730 // Prepare the data we'll use for payee-to-payer search by
731 // inserting first hops suggested by the caller as targets.
732 // Our search will then attempt to reach them while traversing from the payee node.
733 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
734 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
735 if let Some(hops) = first_hops {
737 if chan.short_channel_id.is_none() {
738 panic!("first_hops should be filled in with usable channels, not pending ones");
740 if chan.counterparty.node_id == *our_node_pubkey {
741 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
744 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
745 .or_insert(Vec::new())
748 if first_hop_targets.is_empty() {
749 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
753 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
754 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
755 // adding duplicate entries when we find a better path to a given node.
756 let mut targets = BinaryHeap::new();
758 // Map from node_id to information about the best current path to that node, including feerate
760 let mut dist = HashMap::with_capacity(network_nodes.len());
762 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
763 // indicating that we may wish to try again with a higher value, potentially paying to meet an
764 // htlc_minimum with extra fees while still finding a cheaper path.
765 let mut hit_minimum_limit;
767 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
768 // We start with a path_value of the exact amount we want, and if that generates a route we may
769 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
770 // amount we want in total across paths, selecting the best subset at the end.
771 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
772 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
773 let mut path_value_msat = final_value_msat;
775 // We don't want multiple paths (as per MPP) share liquidity of the same channels.
776 // This map allows paths to be aware of the channel use by other paths in the same call.
777 // This would help to make a better path finding decisions and not "overbook" channels.
778 // It is unaware of the directions (except for `outbound_capacity_msat` in `first_hops`).
779 let mut bookkept_channels_liquidity_available_msat = HashMap::with_capacity(network_nodes.len());
781 // Keeping track of how much value we already collected across other paths. Helps to decide:
782 // - how much a new path should be transferring (upper bound);
783 // - whether a channel should be disregarded because
784 // it's available liquidity is too small comparing to how much more we need to collect;
785 // - when we want to stop looking for new paths.
786 let mut already_collected_value_msat = 0;
788 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payee.pubkey, our_node_pubkey, final_value_msat);
790 macro_rules! add_entry {
791 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
792 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
793 // since that value has to be transferred over this channel.
794 // Returns whether this channel caused an update to `targets`.
795 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
796 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
797 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => { {
798 // We "return" whether we updated the path at the end, via this:
799 let mut did_add_update_path_to_src_node = false;
800 // Channels to self should not be used. This is more of belt-and-suspenders, because in
801 // practice these cases should be caught earlier:
802 // - for regular channels at channel announcement (TODO)
803 // - for first and last hops early in get_route
804 if $src_node_id != $dest_node_id {
805 let short_channel_id = $candidate.short_channel_id();
806 let available_liquidity_msat = bookkept_channels_liquidity_available_msat
807 .entry(short_channel_id)
808 .or_insert_with(|| $candidate.effective_capacity().as_msat());
810 // It is tricky to substract $next_hops_fee_msat from available liquidity here.
811 // It may be misleading because we might later choose to reduce the value transferred
812 // over these channels, and the channel which was insufficient might become sufficient.
813 // Worst case: we drop a good channel here because it can't cover the high following
814 // fees caused by one expensive channel, but then this channel could have been used
815 // if the amount being transferred over this path is lower.
816 // We do this for now, but this is a subject for removal.
817 if let Some(available_value_contribution_msat) = available_liquidity_msat.checked_sub($next_hops_fee_msat) {
819 // Routing Fragmentation Mitigation heuristic:
821 // Routing fragmentation across many payment paths increases the overall routing
822 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
823 // Taking too many smaller paths also increases the chance of payment failure.
824 // Thus to avoid this effect, we require from our collected links to provide
825 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
827 // This requirement is currently 5% of the remaining-to-be-collected value.
828 // This means as we successfully advance in our collection,
829 // the absolute liquidity contribution is lowered,
830 // thus increasing the number of potential channels to be selected.
832 // Derive the minimal liquidity contribution with a ratio of 20 (5%, rounded up)
833 // or 100% if we're not allowed to do multipath payments.
834 let minimal_value_contribution_msat: u64 = if allow_mpp {
835 (recommended_value_msat - already_collected_value_msat + 19) / 20
839 // Verify the liquidity offered by this channel complies to the minimal contribution.
840 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
842 // Do not consider candidates that exceed the maximum total cltv expiry limit.
843 let max_total_cltv_expiry_delta = payee.max_total_cltv_expiry_delta;
844 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
845 .checked_add($candidate.cltv_expiry_delta())
846 .unwrap_or(u32::max_value());
847 let doesnt_exceed_cltv_delta_limit = hop_total_cltv_delta <= max_total_cltv_expiry_delta;
849 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
850 // Includes paying fees for the use of the following channels.
851 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
852 Some(result) => result,
853 // Can't overflow due to how the values were computed right above.
854 None => unreachable!(),
856 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
857 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
858 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
860 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
861 // bother considering this channel.
862 // Since we're choosing amount_to_transfer_over_msat as maximum possible, it can
863 // be only reduced later (not increased), so this channel should just be skipped
864 // as not sufficient.
865 if !over_path_minimum_msat && doesnt_exceed_cltv_delta_limit {
866 hit_minimum_limit = true;
867 } else if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit {
868 // Note that low contribution here (limited by available_liquidity_msat)
869 // might violate htlc_minimum_msat on the hops which are next along the
870 // payment path (upstream to the payee). To avoid that, we recompute
871 // path fees knowing the final path contribution after constructing it.
872 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
873 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
874 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
875 .unwrap_or_else(|| u64::max_value());
876 let hm_entry = dist.entry($src_node_id);
877 let old_entry = hm_entry.or_insert_with(|| {
878 // If there was previously no known way to access the source node
879 // (recall it goes payee-to-payer) of short_channel_id, first add a
880 // semi-dummy record just to compute the fees to reach the source node.
881 // This will affect our decision on selecting short_channel_id
882 // as a way to reach the $dest_node_id.
883 let mut fee_base_msat = u32::max_value();
884 let mut fee_proportional_millionths = u32::max_value();
885 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
886 fee_base_msat = fees.base_msat;
887 fee_proportional_millionths = fees.proportional_millionths;
890 node_id: $dest_node_id.clone(),
891 candidate: $candidate.clone(),
893 src_lowest_inbound_fees: RoutingFees {
894 base_msat: fee_base_msat,
895 proportional_millionths: fee_proportional_millionths,
897 next_hops_fee_msat: u64::max_value(),
898 hop_use_fee_msat: u64::max_value(),
899 total_fee_msat: u64::max_value(),
900 path_htlc_minimum_msat,
901 path_penalty_msat: u64::max_value(),
902 was_processed: false,
903 #[cfg(any(test, feature = "fuzztarget"))]
904 value_contribution_msat,
908 #[allow(unused_mut)] // We only use the mut in cfg(test)
909 let mut should_process = !old_entry.was_processed;
910 #[cfg(any(test, feature = "fuzztarget"))]
912 // In test/fuzzing builds, we do extra checks to make sure the skipping
913 // of already-seen nodes only happens in cases we expect (see below).
914 if !should_process { should_process = true; }
918 let mut hop_use_fee_msat = 0;
919 let mut total_fee_msat = $next_hops_fee_msat;
921 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
922 // will have the same effective-fee
923 if $src_node_id != our_node_id {
924 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
925 // max_value means we'll always fail
926 // the old_entry.total_fee_msat > total_fee_msat check
927 None => total_fee_msat = u64::max_value(),
929 hop_use_fee_msat = fee_msat;
930 total_fee_msat += hop_use_fee_msat;
931 // When calculating the lowest inbound fees to a node, we
932 // calculate fees here not based on the actual value we think
933 // will flow over this channel, but on the minimum value that
934 // we'll accept flowing over it. The minimum accepted value
935 // is a constant through each path collection run, ensuring
936 // consistent basis. Otherwise we may later find a
937 // different path to the source node that is more expensive,
938 // but which we consider to be cheaper because we are capacity
939 // constrained and the relative fee becomes lower.
940 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
941 .map(|a| a.checked_add(total_fee_msat)) {
946 total_fee_msat = u64::max_value();
953 let path_penalty_msat = $next_hops_path_penalty_msat.checked_add(
954 scorer.channel_penalty_msat(short_channel_id, amount_to_transfer_over_msat, *available_liquidity_msat,
955 &$src_node_id, &$dest_node_id)).unwrap_or_else(|| u64::max_value());
956 let new_graph_node = RouteGraphNode {
957 node_id: $src_node_id,
958 lowest_fee_to_peer_through_node: total_fee_msat,
959 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
960 total_cltv_delta: hop_total_cltv_delta,
961 value_contribution_msat: value_contribution_msat,
962 path_htlc_minimum_msat,
966 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
967 // if this way is cheaper than the already known
968 // (considering the cost to "reach" this channel from the route destination,
969 // the cost of using this channel,
970 // and the cost of routing to the source node of this channel).
971 // Also, consider that htlc_minimum_msat_difference, because we might end up
972 // paying it. Consider the following exploit:
973 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
974 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
975 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
976 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
978 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
979 // but it may require additional tracking - we don't want to double-count
980 // the fees included in $next_hops_path_htlc_minimum_msat, but also
981 // can't use something that may decrease on future hops.
982 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
983 .checked_add(old_entry.path_penalty_msat)
984 .unwrap_or_else(|| u64::max_value());
985 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
986 .checked_add(path_penalty_msat)
987 .unwrap_or_else(|| u64::max_value());
989 if !old_entry.was_processed && new_cost < old_cost {
990 targets.push(new_graph_node);
991 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
992 old_entry.hop_use_fee_msat = hop_use_fee_msat;
993 old_entry.total_fee_msat = total_fee_msat;
994 old_entry.node_id = $dest_node_id.clone();
995 old_entry.candidate = $candidate.clone();
996 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
997 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
998 old_entry.path_penalty_msat = path_penalty_msat;
999 #[cfg(any(test, feature = "fuzztarget"))]
1001 old_entry.value_contribution_msat = value_contribution_msat;
1003 did_add_update_path_to_src_node = true;
1004 } else if old_entry.was_processed && new_cost < old_cost {
1005 #[cfg(any(test, feature = "fuzztarget"))]
1007 // If we're skipping processing a node which was previously
1008 // processed even though we found another path to it with a
1009 // cheaper fee, check that it was because the second path we
1010 // found (which we are processing now) has a lower value
1011 // contribution due to an HTLC minimum limit.
1013 // e.g. take a graph with two paths from node 1 to node 2, one
1014 // through channel A, and one through channel B. Channel A and
1015 // B are both in the to-process heap, with their scores set by
1016 // a higher htlc_minimum than fee.
1017 // Channel A is processed first, and the channels onwards from
1018 // node 1 are added to the to-process heap. Thereafter, we pop
1019 // Channel B off of the heap, note that it has a much more
1020 // restrictive htlc_maximum_msat, and recalculate the fees for
1021 // all of node 1's channels using the new, reduced, amount.
1023 // This would be bogus - we'd be selecting a higher-fee path
1024 // with a lower htlc_maximum_msat instead of the one we'd
1025 // already decided to use.
1026 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1028 value_contribution_msat + path_penalty_msat <
1029 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1037 did_add_update_path_to_src_node
1041 let empty_node_features = NodeFeatures::empty();
1042 // Find ways (channels with destination) to reach a given node and store them
1043 // in the corresponding data structures (routing graph etc).
1044 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1045 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1046 // This data can later be helpful to optimize routing (pay lower fees).
1047 macro_rules! add_entries_to_cheapest_to_target_node {
1048 ( $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, $next_hops_cltv_delta: expr ) => {
1049 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1050 let was_processed = elem.was_processed;
1051 elem.was_processed = true;
1054 // Entries are added to dist in add_entry!() when there is a channel from a node.
1055 // Because there are no channels from payee, it will not have a dist entry at this point.
1056 // If we're processing any other node, it is always be the result of a channel from it.
1057 assert_eq!($node_id, payee_node_id);
1062 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1063 for details in first_channels {
1064 let candidate = CandidateRouteHop::FirstHop { details };
1065 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);
1069 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1072 &empty_node_features
1075 if !features.requires_unknown_bits() {
1076 for chan_id in $node.channels.iter() {
1077 let chan = network_channels.get(chan_id).unwrap();
1078 if !chan.features.requires_unknown_bits() {
1079 let directed_channel =
1080 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1081 let source = directed_channel.source();
1082 let target = directed_channel.target();
1083 if first_hops.is_none() || *source != our_node_id {
1084 if let Some(direction) = directed_channel.direction() {
1085 if direction.enabled {
1086 let candidate = CandidateRouteHop::PublicHop {
1087 info: directed_channel,
1088 short_channel_id: *chan_id,
1090 add_entry!(candidate, *source, *target, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1101 let mut payment_paths = Vec::<PaymentPath>::new();
1103 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1104 'paths_collection: loop {
1105 // For every new path, start from scratch, except
1106 // bookkept_channels_liquidity_available_msat, which will improve
1107 // the further iterations of path finding. Also don't erase first_hop_targets.
1110 hit_minimum_limit = false;
1112 // If first hop is a private channel and the only way to reach the payee, this is the only
1113 // place where it could be added.
1114 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1115 for details in first_channels {
1116 let candidate = CandidateRouteHop::FirstHop { details };
1117 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1118 log_trace!(logger, "{} direct route to payee via SCID {}", if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1122 // Add the payee as a target, so that the payee-to-payer
1123 // search algorithm knows what to start with.
1124 match network_nodes.get(&payee_node_id) {
1125 // The payee is not in our network graph, so nothing to add here.
1126 // There is still a chance of reaching them via last_hops though,
1127 // so don't yet fail the payment here.
1128 // If not, targets.pop() will not even let us enter the loop in step 2.
1131 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1136 // If a caller provided us with last hops, add them to routing targets. Since this happens
1137 // earlier than general path finding, they will be somewhat prioritized, although currently
1138 // it matters only if the fees are exactly the same.
1139 for route in payee.route_hints.iter().filter(|route| !route.0.is_empty()) {
1140 let first_hop_in_route = &(route.0)[0];
1141 let have_hop_src_in_graph =
1142 // Only add the hops in this route to our candidate set if either
1143 // we have a direct channel to the first hop or the first hop is
1144 // in the regular network graph.
1145 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1146 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1147 if have_hop_src_in_graph {
1148 // We start building the path from reverse, i.e., from payee
1149 // to the first RouteHintHop in the path.
1150 let hop_iter = route.0.iter().rev();
1151 let prev_hop_iter = core::iter::once(&payee.pubkey).chain(
1152 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1153 let mut hop_used = true;
1154 let mut aggregate_next_hops_fee_msat: u64 = 0;
1155 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1156 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1157 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1159 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1160 let source = NodeId::from_pubkey(&hop.src_node_id);
1161 let target = NodeId::from_pubkey(&prev_hop_id);
1162 let candidate = network_channels
1163 .get(&hop.short_channel_id)
1164 .and_then(|channel| channel.as_directed_to(&target))
1165 .and_then(|channel| channel.direction().map(|_| channel))
1166 .map(|info| CandidateRouteHop::PublicHop {
1168 short_channel_id: hop.short_channel_id,
1170 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1171 let capacity_msat = candidate.effective_capacity().as_msat();
1172 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1173 .checked_add(scorer.channel_penalty_msat(hop.short_channel_id, final_value_msat, capacity_msat, &source, &target))
1174 .unwrap_or_else(|| u64::max_value());
1176 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1177 .checked_add(hop.cltv_expiry_delta as u32)
1178 .unwrap_or_else(|| u32::max_value());
1180 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) {
1181 // If this hop was not used then there is no use checking the preceding hops
1182 // in the RouteHint. We can break by just searching for a direct channel between
1183 // last checked hop and first_hop_targets
1187 // Searching for a direct channel between last checked hop and first_hop_targets
1188 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1189 for details in first_channels {
1190 let candidate = CandidateRouteHop::FirstHop { details };
1191 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);
1199 // In the next values of the iterator, the aggregate fees already reflects
1200 // the sum of value sent from payer (final_value_msat) and routing fees
1201 // for the last node in the RouteHint. We need to just add the fees to
1202 // route through the current node so that the preceeding node (next iteration)
1204 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1205 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1206 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1208 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1209 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1210 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1211 .checked_add(hop_htlc_minimum_msat_inc);
1212 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1214 if idx == route.0.len() - 1 {
1215 // The last hop in this iterator is the first hop in
1216 // overall RouteHint.
1217 // If this hop connects to a node with which we have a direct channel,
1218 // ignore the network graph and, if the last hop was added, add our
1219 // direct channel to the candidate set.
1221 // Note that we *must* check if the last hop was added as `add_entry`
1222 // always assumes that the third argument is a node to which we have a
1224 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1225 for details in first_channels {
1226 let candidate = CandidateRouteHop::FirstHop { details };
1227 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);
1235 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1237 // At this point, targets are filled with the data from first and
1238 // last hops communicated by the caller, and the payment receiver.
1239 let mut found_new_path = false;
1242 // If this loop terminates due the exhaustion of targets, two situations are possible:
1243 // - not enough outgoing liquidity:
1244 // 0 < already_collected_value_msat < final_value_msat
1245 // - enough outgoing liquidity:
1246 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1247 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1248 // paths_collection will be stopped because found_new_path==false.
1249 // This is not necessarily a routing failure.
1250 '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() {
1252 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1253 // traversing the graph and arrange the path out of what we found.
1254 if node_id == our_node_id {
1255 let mut new_entry = dist.remove(&our_node_id).unwrap();
1256 let mut ordered_hops = vec!((new_entry.clone(), NodeFeatures::empty()));
1259 let mut features_set = false;
1260 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1261 for details in first_channels {
1262 if details.short_channel_id.unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1263 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1264 features_set = true;
1270 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1271 if let Some(node_info) = node.announcement_info.as_ref() {
1272 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1274 ordered_hops.last_mut().unwrap().1 = NodeFeatures::empty();
1277 // We should be able to fill in features for everything except the last
1278 // hop, if the last hop was provided via a BOLT 11 invoice (though we
1279 // should be able to extend it further as BOLT 11 does have feature
1280 // flags for the last hop node itself).
1281 assert!(ordered_hops.last().unwrap().0.node_id == payee_node_id);
1285 // Means we succesfully traversed from the payer to the payee, now
1286 // save this path for the payment route. Also, update the liquidity
1287 // remaining on the used hops, so that we take them into account
1288 // while looking for more paths.
1289 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1293 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1294 Some(payment_hop) => payment_hop,
1295 // We can't arrive at None because, if we ever add an entry to targets,
1296 // we also fill in the entry in dist (see add_entry!).
1297 None => unreachable!(),
1299 // We "propagate" the fees one hop backward (topologically) here,
1300 // so that fees paid for a HTLC forwarding on the current channel are
1301 // associated with the previous channel (where they will be subtracted).
1302 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1303 ordered_hops.push((new_entry.clone(), NodeFeatures::empty()));
1305 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1306 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1308 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: {:?}",
1309 ordered_hops.len(), value_contribution_msat, ordered_hops);
1311 let mut payment_path = PaymentPath {hops: ordered_hops};
1313 // We could have possibly constructed a slightly inconsistent path: since we reduce
1314 // value being transferred along the way, we could have violated htlc_minimum_msat
1315 // on some channels we already passed (assuming dest->source direction). Here, we
1316 // recompute the fees again, so that if that's the case, we match the currently
1317 // underpaid htlc_minimum_msat with fees.
1318 payment_path.update_value_and_recompute_fees(cmp::min(value_contribution_msat, final_value_msat));
1320 // Since a path allows to transfer as much value as
1321 // the smallest channel it has ("bottleneck"), we should recompute
1322 // the fees so sender HTLC don't overpay fees when traversing
1323 // larger channels than the bottleneck. This may happen because
1324 // when we were selecting those channels we were not aware how much value
1325 // this path will transfer, and the relative fee for them
1326 // might have been computed considering a larger value.
1327 // Remember that we used these channels so that we don't rely
1328 // on the same liquidity in future paths.
1329 let mut prevented_redundant_path_selection = false;
1330 for (payment_hop, _) in payment_path.hops.iter() {
1331 let channel_liquidity_available_msat = bookkept_channels_liquidity_available_msat.get_mut(&payment_hop.candidate.short_channel_id()).unwrap();
1332 let mut spent_on_hop_msat = value_contribution_msat;
1333 let next_hops_fee_msat = payment_hop.next_hops_fee_msat;
1334 spent_on_hop_msat += next_hops_fee_msat;
1335 if spent_on_hop_msat == *channel_liquidity_available_msat {
1336 // If this path used all of this channel's available liquidity, we know
1337 // this path will not be selected again in the next loop iteration.
1338 prevented_redundant_path_selection = true;
1340 *channel_liquidity_available_msat -= spent_on_hop_msat;
1342 if !prevented_redundant_path_selection {
1343 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1344 // we'll probably end up picking the same path again on the next iteration.
1345 // Decrease the available liquidity of a hop in the middle of the path.
1346 let victim_scid = payment_path.hops[(payment_path.hops.len() - 1) / 2].0.candidate.short_channel_id();
1347 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1348 let victim_liquidity = bookkept_channels_liquidity_available_msat.get_mut(&victim_scid).unwrap();
1349 *victim_liquidity = 0;
1352 // Track the total amount all our collected paths allow to send so that we:
1353 // - know when to stop looking for more paths
1354 // - know which of the hops are useless considering how much more sats we need
1355 // (contributes_sufficient_value)
1356 already_collected_value_msat += value_contribution_msat;
1358 payment_paths.push(payment_path);
1359 found_new_path = true;
1360 break 'path_construction;
1363 // If we found a path back to the payee, we shouldn't try to process it again. This is
1364 // the equivalent of the `elem.was_processed` check in
1365 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1366 if node_id == payee_node_id { continue 'path_construction; }
1368 // Otherwise, since the current target node is not us,
1369 // keep "unrolling" the payment graph from payee to payer by
1370 // finding a way to reach the current target from the payer side.
1371 match network_nodes.get(&node_id) {
1374 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);
1380 // If we don't support MPP, no use trying to gather more value ever.
1381 break 'paths_collection;
1385 // Stop either when the recommended value is reached or if no new path was found in this
1387 // In the latter case, making another path finding attempt won't help,
1388 // because we deterministically terminated the search due to low liquidity.
1389 if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1390 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1391 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1392 break 'paths_collection;
1393 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1394 // Further, if this was our first walk of the graph, and we weren't limited by an
1395 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1396 // limited by an htlc_minimum_msat value, find another path with a higher value,
1397 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1398 // still keeping a lower total fee than this path.
1399 if !hit_minimum_limit {
1400 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1401 break 'paths_collection;
1403 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1404 path_value_msat = recommended_value_msat;
1409 if payment_paths.len() == 0 {
1410 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1413 if already_collected_value_msat < final_value_msat {
1414 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1417 // Sort by total fees and take the best paths.
1418 payment_paths.sort_by_key(|path| path.get_total_fee_paid_msat());
1419 if payment_paths.len() > 50 {
1420 payment_paths.truncate(50);
1423 // Draw multiple sufficient routes by randomly combining the selected paths.
1424 let mut drawn_routes = Vec::new();
1425 for i in 0..payment_paths.len() {
1426 let mut cur_route = Vec::<PaymentPath>::new();
1427 let mut aggregate_route_value_msat = 0;
1430 // TODO: real random shuffle
1431 // Currently just starts with i_th and goes up to i-1_th in a looped way.
1432 let cur_payment_paths = [&payment_paths[i..], &payment_paths[..i]].concat();
1435 for payment_path in cur_payment_paths {
1436 cur_route.push(payment_path.clone());
1437 aggregate_route_value_msat += payment_path.get_value_msat();
1438 if aggregate_route_value_msat > final_value_msat {
1439 // Last path likely overpaid. Substract it from the most expensive
1440 // (in terms of proportional fee) path in this route and recompute fees.
1441 // This might be not the most economically efficient way, but fewer paths
1442 // also makes routing more reliable.
1443 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1445 // First, drop some expensive low-value paths entirely if possible.
1446 // Sort by value so that we drop many really-low values first, since
1447 // fewer paths is better: the payment is less likely to fail.
1448 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1449 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1450 cur_route.sort_by_key(|path| path.get_value_msat());
1451 // We should make sure that at least 1 path left.
1452 let mut paths_left = cur_route.len();
1453 cur_route.retain(|path| {
1454 if paths_left == 1 {
1457 let mut keep = true;
1458 let path_value_msat = path.get_value_msat();
1459 if path_value_msat <= overpaid_value_msat {
1461 overpaid_value_msat -= path_value_msat;
1467 if overpaid_value_msat == 0 {
1471 assert!(cur_route.len() > 0);
1474 // Now, substract the overpaid value from the most-expensive path.
1475 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1476 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1477 cur_route.sort_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1478 let expensive_payment_path = cur_route.first_mut().unwrap();
1479 // We already dropped all the small channels above, meaning all the
1480 // remaining channels are larger than remaining overpaid_value_msat.
1481 // Thus, this can't be negative.
1482 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1483 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1487 drawn_routes.push(cur_route);
1491 // Select the best route by lowest total fee.
1492 drawn_routes.sort_by_key(|paths| paths.iter().map(|path| path.get_total_fee_paid_msat()).sum::<u64>());
1493 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1494 for payment_path in drawn_routes.first().unwrap() {
1495 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1497 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)})?,
1498 node_features: node_features.clone(),
1499 short_channel_id: payment_hop.candidate.short_channel_id(),
1500 channel_features: payment_hop.candidate.features(),
1501 fee_msat: payment_hop.fee_msat,
1502 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1504 }).collect::<Vec<_>>();
1505 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1506 // applicable for the previous hop.
1507 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1508 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1510 selected_paths.push(path);
1513 if let Some(features) = &payee.features {
1514 for path in selected_paths.iter_mut() {
1515 if let Ok(route_hop) = path.last_mut().unwrap() {
1516 route_hop.node_features = features.to_context();
1522 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1523 payee: Some(payee.clone()),
1525 log_info!(logger, "Got route to {}: {}", payee.pubkey, log_route!(route));
1531 use routing::scoring::Score;
1532 use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
1533 use routing::router::{get_route, Payee, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees};
1534 use chain::transaction::OutPoint;
1535 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1536 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1537 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1538 use ln::channelmanager;
1539 use util::test_utils;
1540 use util::ser::Writeable;
1542 use util::ser::Writer;
1544 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1545 use bitcoin::hashes::Hash;
1546 use bitcoin::network::constants::Network;
1547 use bitcoin::blockdata::constants::genesis_block;
1548 use bitcoin::blockdata::script::Builder;
1549 use bitcoin::blockdata::opcodes;
1550 use bitcoin::blockdata::transaction::TxOut;
1554 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
1555 use bitcoin::secp256k1::{Secp256k1, All};
1558 use sync::{self, Arc};
1560 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1561 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1562 channelmanager::ChannelDetails {
1563 channel_id: [0; 32],
1564 counterparty: channelmanager::ChannelCounterparty {
1567 unspendable_punishment_reserve: 0,
1568 forwarding_info: None,
1570 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1572 channel_value_satoshis: 0,
1575 outbound_capacity_msat,
1576 inbound_capacity_msat: 42,
1577 unspendable_punishment_reserve: None,
1578 confirmations_required: None,
1579 force_close_spend_delay: None,
1580 is_outbound: true, is_funding_locked: true,
1581 is_usable: true, is_public: true,
1585 // Using the same keys for LN and BTC ids
1587 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1588 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
1590 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
1591 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
1593 let unsigned_announcement = UnsignedChannelAnnouncement {
1595 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1599 bitcoin_key_1: node_id_1,
1600 bitcoin_key_2: node_id_2,
1601 excess_data: Vec::new(),
1604 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1605 let valid_announcement = ChannelAnnouncement {
1606 node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1607 node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1608 bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1609 bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1610 contents: unsigned_announcement.clone(),
1612 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
1613 Ok(res) => assert!(res),
1619 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1620 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
1622 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
1623 let valid_channel_update = ChannelUpdate {
1624 signature: secp_ctx.sign(&msghash, node_privkey),
1625 contents: update.clone()
1628 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
1629 Ok(res) => assert!(res),
1634 fn add_or_update_node(
1635 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1636 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
1638 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
1639 let unsigned_announcement = UnsignedNodeAnnouncement {
1645 addresses: Vec::new(),
1646 excess_address_data: Vec::new(),
1647 excess_data: Vec::new(),
1649 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1650 let valid_announcement = NodeAnnouncement {
1651 signature: secp_ctx.sign(&msghash, node_privkey),
1652 contents: unsigned_announcement.clone()
1655 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
1661 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
1662 let privkeys: Vec<SecretKey> = (2..10).map(|i| {
1663 SecretKey::from_slice(&hex::decode(format!("{:02}", i).repeat(32)).unwrap()[..]).unwrap()
1666 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
1668 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
1669 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
1671 (our_privkey, our_id, privkeys, pubkeys)
1674 fn id_to_feature_flags(id: u8) -> Vec<u8> {
1675 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1676 // test for it later.
1677 let idx = (id - 1) * 2 + 1;
1679 vec![1 << (idx - 8*3), 0, 0, 0]
1680 } else if idx > 8*2 {
1681 vec![1 << (idx - 8*2), 0, 0]
1682 } else if idx > 8*1 {
1683 vec![1 << (idx - 8*1), 0]
1689 fn build_graph() -> (
1691 sync::Arc<NetworkGraph>,
1692 NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
1693 sync::Arc<test_utils::TestChainSource>,
1694 sync::Arc<test_utils::TestLogger>,
1696 let secp_ctx = Secp256k1::new();
1697 let logger = Arc::new(test_utils::TestLogger::new());
1698 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
1699 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
1700 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
1701 // Build network from our_id to node6:
1703 // -1(1)2- node0 -1(3)2-
1705 // our_id -1(12)2- node7 -1(13)2--- node2
1707 // -1(2)2- node1 -1(4)2-
1710 // chan1 1-to-2: disabled
1711 // chan1 2-to-1: enabled, 0 fee
1713 // chan2 1-to-2: enabled, ignored fee
1714 // chan2 2-to-1: enabled, 0 fee
1716 // chan3 1-to-2: enabled, 0 fee
1717 // chan3 2-to-1: enabled, 100 msat fee
1719 // chan4 1-to-2: enabled, 100% fee
1720 // chan4 2-to-1: enabled, 0 fee
1722 // chan12 1-to-2: enabled, ignored fee
1723 // chan12 2-to-1: enabled, 0 fee
1725 // chan13 1-to-2: enabled, 200% fee
1726 // chan13 2-to-1: enabled, 0 fee
1729 // -1(5)2- node3 -1(8)2--
1733 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
1735 // -1(7)2- node5 -1(10)2-
1737 // Channels 5, 8, 9 and 10 are private channels.
1739 // chan5 1-to-2: enabled, 100 msat fee
1740 // chan5 2-to-1: enabled, 0 fee
1742 // chan6 1-to-2: enabled, 0 fee
1743 // chan6 2-to-1: enabled, 0 fee
1745 // chan7 1-to-2: enabled, 100% fee
1746 // chan7 2-to-1: enabled, 0 fee
1748 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
1749 // chan8 2-to-1: enabled, 0 fee
1751 // chan9 1-to-2: enabled, 1001 msat fee
1752 // chan9 2-to-1: enabled, 0 fee
1754 // chan10 1-to-2: enabled, 0 fee
1755 // chan10 2-to-1: enabled, 0 fee
1757 // chan11 1-to-2: enabled, 0 fee
1758 // chan11 2-to-1: enabled, 0 fee
1760 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
1762 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
1763 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1764 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1765 short_channel_id: 1,
1768 cltv_expiry_delta: 0,
1769 htlc_minimum_msat: 0,
1770 htlc_maximum_msat: OptionalField::Absent,
1772 fee_proportional_millionths: 0,
1773 excess_data: Vec::new()
1776 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
1778 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
1779 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1780 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1781 short_channel_id: 2,
1784 cltv_expiry_delta: (5 << 4) | 3,
1785 htlc_minimum_msat: 0,
1786 htlc_maximum_msat: OptionalField::Absent,
1787 fee_base_msat: u32::max_value(),
1788 fee_proportional_millionths: u32::max_value(),
1789 excess_data: Vec::new()
1791 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
1792 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1793 short_channel_id: 2,
1796 cltv_expiry_delta: 0,
1797 htlc_minimum_msat: 0,
1798 htlc_maximum_msat: OptionalField::Absent,
1800 fee_proportional_millionths: 0,
1801 excess_data: Vec::new()
1804 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
1806 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
1807 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1808 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1809 short_channel_id: 12,
1812 cltv_expiry_delta: (5 << 4) | 3,
1813 htlc_minimum_msat: 0,
1814 htlc_maximum_msat: OptionalField::Absent,
1815 fee_base_msat: u32::max_value(),
1816 fee_proportional_millionths: u32::max_value(),
1817 excess_data: Vec::new()
1819 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
1820 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1821 short_channel_id: 12,
1824 cltv_expiry_delta: 0,
1825 htlc_minimum_msat: 0,
1826 htlc_maximum_msat: OptionalField::Absent,
1828 fee_proportional_millionths: 0,
1829 excess_data: Vec::new()
1832 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
1834 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
1835 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1836 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1837 short_channel_id: 3,
1840 cltv_expiry_delta: (3 << 4) | 1,
1841 htlc_minimum_msat: 0,
1842 htlc_maximum_msat: OptionalField::Absent,
1844 fee_proportional_millionths: 0,
1845 excess_data: Vec::new()
1847 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1848 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1849 short_channel_id: 3,
1852 cltv_expiry_delta: (3 << 4) | 2,
1853 htlc_minimum_msat: 0,
1854 htlc_maximum_msat: OptionalField::Absent,
1856 fee_proportional_millionths: 0,
1857 excess_data: Vec::new()
1860 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
1861 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
1862 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1863 short_channel_id: 4,
1866 cltv_expiry_delta: (4 << 4) | 1,
1867 htlc_minimum_msat: 0,
1868 htlc_maximum_msat: OptionalField::Absent,
1870 fee_proportional_millionths: 1000000,
1871 excess_data: Vec::new()
1873 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1874 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1875 short_channel_id: 4,
1878 cltv_expiry_delta: (4 << 4) | 2,
1879 htlc_minimum_msat: 0,
1880 htlc_maximum_msat: OptionalField::Absent,
1882 fee_proportional_millionths: 0,
1883 excess_data: Vec::new()
1886 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
1887 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
1888 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1889 short_channel_id: 13,
1892 cltv_expiry_delta: (13 << 4) | 1,
1893 htlc_minimum_msat: 0,
1894 htlc_maximum_msat: OptionalField::Absent,
1896 fee_proportional_millionths: 2000000,
1897 excess_data: Vec::new()
1899 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1900 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1901 short_channel_id: 13,
1904 cltv_expiry_delta: (13 << 4) | 2,
1905 htlc_minimum_msat: 0,
1906 htlc_maximum_msat: OptionalField::Absent,
1908 fee_proportional_millionths: 0,
1909 excess_data: Vec::new()
1912 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
1914 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
1915 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1916 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1917 short_channel_id: 6,
1920 cltv_expiry_delta: (6 << 4) | 1,
1921 htlc_minimum_msat: 0,
1922 htlc_maximum_msat: OptionalField::Absent,
1924 fee_proportional_millionths: 0,
1925 excess_data: Vec::new()
1927 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
1928 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1929 short_channel_id: 6,
1932 cltv_expiry_delta: (6 << 4) | 2,
1933 htlc_minimum_msat: 0,
1934 htlc_maximum_msat: OptionalField::Absent,
1936 fee_proportional_millionths: 0,
1937 excess_data: Vec::new(),
1940 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
1941 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
1942 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1943 short_channel_id: 11,
1946 cltv_expiry_delta: (11 << 4) | 1,
1947 htlc_minimum_msat: 0,
1948 htlc_maximum_msat: OptionalField::Absent,
1950 fee_proportional_millionths: 0,
1951 excess_data: Vec::new()
1953 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
1954 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1955 short_channel_id: 11,
1958 cltv_expiry_delta: (11 << 4) | 2,
1959 htlc_minimum_msat: 0,
1960 htlc_maximum_msat: OptionalField::Absent,
1962 fee_proportional_millionths: 0,
1963 excess_data: Vec::new()
1966 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
1968 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
1970 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
1971 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1972 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1973 short_channel_id: 7,
1976 cltv_expiry_delta: (7 << 4) | 1,
1977 htlc_minimum_msat: 0,
1978 htlc_maximum_msat: OptionalField::Absent,
1980 fee_proportional_millionths: 1000000,
1981 excess_data: Vec::new()
1983 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
1984 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1985 short_channel_id: 7,
1988 cltv_expiry_delta: (7 << 4) | 2,
1989 htlc_minimum_msat: 0,
1990 htlc_maximum_msat: OptionalField::Absent,
1992 fee_proportional_millionths: 0,
1993 excess_data: Vec::new()
1996 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
1998 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
2002 fn simple_route_test() {
2003 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2004 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2005 let payee = Payee::from_node_id(nodes[2]);
2006 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2008 // Simple route to 2 via 1
2010 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, None, 0, 42, Arc::clone(&logger), &scorer) {
2011 assert_eq!(err, "Cannot send a payment of 0 msat");
2012 } else { panic!(); }
2014 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2015 assert_eq!(route.paths[0].len(), 2);
2017 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2018 assert_eq!(route.paths[0][0].short_channel_id, 2);
2019 assert_eq!(route.paths[0][0].fee_msat, 100);
2020 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2021 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2022 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2024 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2025 assert_eq!(route.paths[0][1].short_channel_id, 4);
2026 assert_eq!(route.paths[0][1].fee_msat, 100);
2027 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2028 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2029 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2033 fn invalid_first_hop_test() {
2034 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2035 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2036 let payee = Payee::from_node_id(nodes[2]);
2037 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2039 // Simple route to 2 via 1
2041 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2043 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer) {
2044 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2045 } else { panic!(); }
2047 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2048 assert_eq!(route.paths[0].len(), 2);
2052 fn htlc_minimum_test() {
2053 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2054 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2055 let payee = Payee::from_node_id(nodes[2]);
2056 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2058 // Simple route to 2 via 1
2060 // Disable other paths
2061 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2062 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2063 short_channel_id: 12,
2065 flags: 2, // to disable
2066 cltv_expiry_delta: 0,
2067 htlc_minimum_msat: 0,
2068 htlc_maximum_msat: OptionalField::Absent,
2070 fee_proportional_millionths: 0,
2071 excess_data: Vec::new()
2073 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2074 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2075 short_channel_id: 3,
2077 flags: 2, // to disable
2078 cltv_expiry_delta: 0,
2079 htlc_minimum_msat: 0,
2080 htlc_maximum_msat: OptionalField::Absent,
2082 fee_proportional_millionths: 0,
2083 excess_data: Vec::new()
2085 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2086 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2087 short_channel_id: 13,
2089 flags: 2, // to disable
2090 cltv_expiry_delta: 0,
2091 htlc_minimum_msat: 0,
2092 htlc_maximum_msat: OptionalField::Absent,
2094 fee_proportional_millionths: 0,
2095 excess_data: Vec::new()
2097 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2098 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2099 short_channel_id: 6,
2101 flags: 2, // to disable
2102 cltv_expiry_delta: 0,
2103 htlc_minimum_msat: 0,
2104 htlc_maximum_msat: OptionalField::Absent,
2106 fee_proportional_millionths: 0,
2107 excess_data: Vec::new()
2109 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2110 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2111 short_channel_id: 7,
2113 flags: 2, // to disable
2114 cltv_expiry_delta: 0,
2115 htlc_minimum_msat: 0,
2116 htlc_maximum_msat: OptionalField::Absent,
2118 fee_proportional_millionths: 0,
2119 excess_data: Vec::new()
2122 // Check against amount_to_transfer_over_msat.
2123 // Set minimal HTLC of 200_000_000 msat.
2124 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2125 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2126 short_channel_id: 2,
2129 cltv_expiry_delta: 0,
2130 htlc_minimum_msat: 200_000_000,
2131 htlc_maximum_msat: OptionalField::Absent,
2133 fee_proportional_millionths: 0,
2134 excess_data: Vec::new()
2137 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2139 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2140 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2141 short_channel_id: 4,
2144 cltv_expiry_delta: 0,
2145 htlc_minimum_msat: 0,
2146 htlc_maximum_msat: OptionalField::Present(199_999_999),
2148 fee_proportional_millionths: 0,
2149 excess_data: Vec::new()
2152 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2153 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, None, 199_999_999, 42, Arc::clone(&logger), &scorer) {
2154 assert_eq!(err, "Failed to find a path to the given destination");
2155 } else { panic!(); }
2157 // Lift the restriction on the first hop.
2158 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2159 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2160 short_channel_id: 2,
2163 cltv_expiry_delta: 0,
2164 htlc_minimum_msat: 0,
2165 htlc_maximum_msat: OptionalField::Absent,
2167 fee_proportional_millionths: 0,
2168 excess_data: Vec::new()
2171 // A payment above the minimum should pass
2172 let route = get_route(&our_id, &payee, &network_graph, None, 199_999_999, 42, Arc::clone(&logger), &scorer).unwrap();
2173 assert_eq!(route.paths[0].len(), 2);
2177 fn htlc_minimum_overpay_test() {
2178 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2179 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2180 let payee = Payee::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2181 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2183 // A route to node#2 via two paths.
2184 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2185 // Thus, they can't send 60 without overpaying.
2186 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2187 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2188 short_channel_id: 2,
2191 cltv_expiry_delta: 0,
2192 htlc_minimum_msat: 35_000,
2193 htlc_maximum_msat: OptionalField::Present(40_000),
2195 fee_proportional_millionths: 0,
2196 excess_data: Vec::new()
2198 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2199 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2200 short_channel_id: 12,
2203 cltv_expiry_delta: 0,
2204 htlc_minimum_msat: 35_000,
2205 htlc_maximum_msat: OptionalField::Present(40_000),
2207 fee_proportional_millionths: 0,
2208 excess_data: Vec::new()
2212 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2213 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2214 short_channel_id: 13,
2217 cltv_expiry_delta: 0,
2218 htlc_minimum_msat: 0,
2219 htlc_maximum_msat: OptionalField::Absent,
2221 fee_proportional_millionths: 0,
2222 excess_data: Vec::new()
2224 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2225 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2226 short_channel_id: 4,
2229 cltv_expiry_delta: 0,
2230 htlc_minimum_msat: 0,
2231 htlc_maximum_msat: OptionalField::Absent,
2233 fee_proportional_millionths: 0,
2234 excess_data: Vec::new()
2237 // Disable other paths
2238 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2239 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2240 short_channel_id: 1,
2242 flags: 2, // to disable
2243 cltv_expiry_delta: 0,
2244 htlc_minimum_msat: 0,
2245 htlc_maximum_msat: OptionalField::Absent,
2247 fee_proportional_millionths: 0,
2248 excess_data: Vec::new()
2251 let route = get_route(&our_id, &payee, &network_graph, None, 60_000, 42, Arc::clone(&logger), &scorer).unwrap();
2252 // Overpay fees to hit htlc_minimum_msat.
2253 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2254 // TODO: this could be better balanced to overpay 10k and not 15k.
2255 assert_eq!(overpaid_fees, 15_000);
2257 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2258 // while taking even more fee to match htlc_minimum_msat.
2259 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2260 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2261 short_channel_id: 12,
2264 cltv_expiry_delta: 0,
2265 htlc_minimum_msat: 65_000,
2266 htlc_maximum_msat: OptionalField::Present(80_000),
2268 fee_proportional_millionths: 0,
2269 excess_data: Vec::new()
2271 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2272 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2273 short_channel_id: 2,
2276 cltv_expiry_delta: 0,
2277 htlc_minimum_msat: 0,
2278 htlc_maximum_msat: OptionalField::Absent,
2280 fee_proportional_millionths: 0,
2281 excess_data: Vec::new()
2283 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2284 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2285 short_channel_id: 4,
2288 cltv_expiry_delta: 0,
2289 htlc_minimum_msat: 0,
2290 htlc_maximum_msat: OptionalField::Absent,
2292 fee_proportional_millionths: 100_000,
2293 excess_data: Vec::new()
2296 let route = get_route(&our_id, &payee, &network_graph, None, 60_000, 42, Arc::clone(&logger), &scorer).unwrap();
2297 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2298 assert_eq!(route.paths.len(), 1);
2299 assert_eq!(route.paths[0][0].short_channel_id, 12);
2300 let fees = route.paths[0][0].fee_msat;
2301 assert_eq!(fees, 5_000);
2303 let route = get_route(&our_id, &payee, &network_graph, None, 50_000, 42, Arc::clone(&logger), &scorer).unwrap();
2304 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2305 // the other channel.
2306 assert_eq!(route.paths.len(), 1);
2307 assert_eq!(route.paths[0][0].short_channel_id, 2);
2308 let fees = route.paths[0][0].fee_msat;
2309 assert_eq!(fees, 5_000);
2313 fn disable_channels_test() {
2314 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2315 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2316 let payee = Payee::from_node_id(nodes[2]);
2317 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2319 // // Disable channels 4 and 12 by flags=2
2320 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2321 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2322 short_channel_id: 4,
2324 flags: 2, // to disable
2325 cltv_expiry_delta: 0,
2326 htlc_minimum_msat: 0,
2327 htlc_maximum_msat: OptionalField::Absent,
2329 fee_proportional_millionths: 0,
2330 excess_data: Vec::new()
2332 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2333 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2334 short_channel_id: 12,
2336 flags: 2, // to disable
2337 cltv_expiry_delta: 0,
2338 htlc_minimum_msat: 0,
2339 htlc_maximum_msat: OptionalField::Absent,
2341 fee_proportional_millionths: 0,
2342 excess_data: Vec::new()
2345 // If all the channels require some features we don't understand, route should fail
2346 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer) {
2347 assert_eq!(err, "Failed to find a path to the given destination");
2348 } else { panic!(); }
2350 // If we specify a channel to node7, that overrides our local channel view and that gets used
2351 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2352 let route = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer).unwrap();
2353 assert_eq!(route.paths[0].len(), 2);
2355 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2356 assert_eq!(route.paths[0][0].short_channel_id, 42);
2357 assert_eq!(route.paths[0][0].fee_msat, 200);
2358 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2359 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2360 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2362 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2363 assert_eq!(route.paths[0][1].short_channel_id, 13);
2364 assert_eq!(route.paths[0][1].fee_msat, 100);
2365 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2366 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2367 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2371 fn disable_node_test() {
2372 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2373 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2374 let payee = Payee::from_node_id(nodes[2]);
2375 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2377 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2378 let unknown_features = NodeFeatures::known().set_unknown_feature_required();
2379 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2380 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2381 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2383 // If all nodes require some features we don't understand, route should fail
2384 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer) {
2385 assert_eq!(err, "Failed to find a path to the given destination");
2386 } else { panic!(); }
2388 // If we specify a channel to node7, that overrides our local channel view and that gets used
2389 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2390 let route = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer).unwrap();
2391 assert_eq!(route.paths[0].len(), 2);
2393 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2394 assert_eq!(route.paths[0][0].short_channel_id, 42);
2395 assert_eq!(route.paths[0][0].fee_msat, 200);
2396 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2397 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2398 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2400 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2401 assert_eq!(route.paths[0][1].short_channel_id, 13);
2402 assert_eq!(route.paths[0][1].fee_msat, 100);
2403 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2404 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2405 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2407 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2408 // naively) assume that the user checked the feature bits on the invoice, which override
2409 // the node_announcement.
2413 fn our_chans_test() {
2414 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2415 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2416 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2418 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2419 let payee = Payee::from_node_id(nodes[0]);
2420 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2421 assert_eq!(route.paths[0].len(), 3);
2423 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2424 assert_eq!(route.paths[0][0].short_channel_id, 2);
2425 assert_eq!(route.paths[0][0].fee_msat, 200);
2426 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2427 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2428 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2430 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2431 assert_eq!(route.paths[0][1].short_channel_id, 4);
2432 assert_eq!(route.paths[0][1].fee_msat, 100);
2433 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2434 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2435 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2437 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2438 assert_eq!(route.paths[0][2].short_channel_id, 3);
2439 assert_eq!(route.paths[0][2].fee_msat, 100);
2440 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2441 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2442 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2444 // If we specify a channel to node7, that overrides our local channel view and that gets used
2445 let payee = Payee::from_node_id(nodes[2]);
2446 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2447 let route = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer).unwrap();
2448 assert_eq!(route.paths[0].len(), 2);
2450 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2451 assert_eq!(route.paths[0][0].short_channel_id, 42);
2452 assert_eq!(route.paths[0][0].fee_msat, 200);
2453 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2454 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2455 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2457 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2458 assert_eq!(route.paths[0][1].short_channel_id, 13);
2459 assert_eq!(route.paths[0][1].fee_msat, 100);
2460 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2461 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2462 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2465 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2466 let zero_fees = RoutingFees {
2468 proportional_millionths: 0,
2470 vec![RouteHint(vec![RouteHintHop {
2471 src_node_id: nodes[3],
2472 short_channel_id: 8,
2474 cltv_expiry_delta: (8 << 4) | 1,
2475 htlc_minimum_msat: None,
2476 htlc_maximum_msat: None,
2478 ]), RouteHint(vec![RouteHintHop {
2479 src_node_id: nodes[4],
2480 short_channel_id: 9,
2483 proportional_millionths: 0,
2485 cltv_expiry_delta: (9 << 4) | 1,
2486 htlc_minimum_msat: None,
2487 htlc_maximum_msat: None,
2488 }]), RouteHint(vec![RouteHintHop {
2489 src_node_id: nodes[5],
2490 short_channel_id: 10,
2492 cltv_expiry_delta: (10 << 4) | 1,
2493 htlc_minimum_msat: None,
2494 htlc_maximum_msat: None,
2498 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2499 let zero_fees = RoutingFees {
2501 proportional_millionths: 0,
2503 vec![RouteHint(vec![RouteHintHop {
2504 src_node_id: nodes[2],
2505 short_channel_id: 5,
2508 proportional_millionths: 0,
2510 cltv_expiry_delta: (5 << 4) | 1,
2511 htlc_minimum_msat: None,
2512 htlc_maximum_msat: None,
2514 src_node_id: nodes[3],
2515 short_channel_id: 8,
2517 cltv_expiry_delta: (8 << 4) | 1,
2518 htlc_minimum_msat: None,
2519 htlc_maximum_msat: None,
2521 ]), RouteHint(vec![RouteHintHop {
2522 src_node_id: nodes[4],
2523 short_channel_id: 9,
2526 proportional_millionths: 0,
2528 cltv_expiry_delta: (9 << 4) | 1,
2529 htlc_minimum_msat: None,
2530 htlc_maximum_msat: None,
2531 }]), RouteHint(vec![RouteHintHop {
2532 src_node_id: nodes[5],
2533 short_channel_id: 10,
2535 cltv_expiry_delta: (10 << 4) | 1,
2536 htlc_minimum_msat: None,
2537 htlc_maximum_msat: None,
2542 fn partial_route_hint_test() {
2543 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2544 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2545 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2547 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2548 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2549 // RouteHint may be partially used by the algo to build the best path.
2551 // First check that last hop can't have its source as the payee.
2552 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2553 src_node_id: nodes[6],
2554 short_channel_id: 8,
2557 proportional_millionths: 0,
2559 cltv_expiry_delta: (8 << 4) | 1,
2560 htlc_minimum_msat: None,
2561 htlc_maximum_msat: None,
2564 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2565 invalid_last_hops.push(invalid_last_hop);
2567 let payee = Payee::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2568 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer) {
2569 assert_eq!(err, "Route hint cannot have the payee as the source.");
2570 } else { panic!(); }
2573 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2574 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2575 assert_eq!(route.paths[0].len(), 5);
2577 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2578 assert_eq!(route.paths[0][0].short_channel_id, 2);
2579 assert_eq!(route.paths[0][0].fee_msat, 100);
2580 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2581 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2582 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2584 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2585 assert_eq!(route.paths[0][1].short_channel_id, 4);
2586 assert_eq!(route.paths[0][1].fee_msat, 0);
2587 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2588 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2589 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2591 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2592 assert_eq!(route.paths[0][2].short_channel_id, 6);
2593 assert_eq!(route.paths[0][2].fee_msat, 0);
2594 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2595 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2596 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2598 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2599 assert_eq!(route.paths[0][3].short_channel_id, 11);
2600 assert_eq!(route.paths[0][3].fee_msat, 0);
2601 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2602 // If we have a peer in the node map, we'll use their features here since we don't have
2603 // a way of figuring out their features from the invoice:
2604 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2605 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2607 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2608 assert_eq!(route.paths[0][4].short_channel_id, 8);
2609 assert_eq!(route.paths[0][4].fee_msat, 100);
2610 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2611 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2612 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2615 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2616 let zero_fees = RoutingFees {
2618 proportional_millionths: 0,
2620 vec![RouteHint(vec![RouteHintHop {
2621 src_node_id: nodes[3],
2622 short_channel_id: 8,
2624 cltv_expiry_delta: (8 << 4) | 1,
2625 htlc_minimum_msat: None,
2626 htlc_maximum_msat: None,
2627 }]), RouteHint(vec![
2629 ]), RouteHint(vec![RouteHintHop {
2630 src_node_id: nodes[5],
2631 short_channel_id: 10,
2633 cltv_expiry_delta: (10 << 4) | 1,
2634 htlc_minimum_msat: None,
2635 htlc_maximum_msat: None,
2640 fn ignores_empty_last_hops_test() {
2641 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2642 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2643 let payee = Payee::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2644 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2646 // Test handling of an empty RouteHint passed in Invoice.
2648 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2649 assert_eq!(route.paths[0].len(), 5);
2651 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2652 assert_eq!(route.paths[0][0].short_channel_id, 2);
2653 assert_eq!(route.paths[0][0].fee_msat, 100);
2654 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2655 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2656 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2658 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2659 assert_eq!(route.paths[0][1].short_channel_id, 4);
2660 assert_eq!(route.paths[0][1].fee_msat, 0);
2661 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2662 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2663 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2665 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2666 assert_eq!(route.paths[0][2].short_channel_id, 6);
2667 assert_eq!(route.paths[0][2].fee_msat, 0);
2668 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2669 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2670 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2672 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2673 assert_eq!(route.paths[0][3].short_channel_id, 11);
2674 assert_eq!(route.paths[0][3].fee_msat, 0);
2675 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2676 // If we have a peer in the node map, we'll use their features here since we don't have
2677 // a way of figuring out their features from the invoice:
2678 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2679 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2681 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2682 assert_eq!(route.paths[0][4].short_channel_id, 8);
2683 assert_eq!(route.paths[0][4].fee_msat, 100);
2684 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2685 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2686 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2689 fn multi_hint_last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2690 let zero_fees = RoutingFees {
2692 proportional_millionths: 0,
2694 vec![RouteHint(vec![RouteHintHop {
2695 src_node_id: nodes[2],
2696 short_channel_id: 5,
2699 proportional_millionths: 0,
2701 cltv_expiry_delta: (5 << 4) | 1,
2702 htlc_minimum_msat: None,
2703 htlc_maximum_msat: None,
2705 src_node_id: nodes[3],
2706 short_channel_id: 8,
2708 cltv_expiry_delta: (8 << 4) | 1,
2709 htlc_minimum_msat: None,
2710 htlc_maximum_msat: None,
2711 }]), RouteHint(vec![RouteHintHop {
2712 src_node_id: nodes[5],
2713 short_channel_id: 10,
2715 cltv_expiry_delta: (10 << 4) | 1,
2716 htlc_minimum_msat: None,
2717 htlc_maximum_msat: None,
2722 fn multi_hint_last_hops_test() {
2723 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2724 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2725 let payee = Payee::from_node_id(nodes[6]).with_route_hints(multi_hint_last_hops(&nodes));
2726 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2727 // Test through channels 2, 3, 5, 8.
2728 // Test shows that multiple hop hints are considered.
2730 // Disabling channels 6 & 7 by flags=2
2731 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2732 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2733 short_channel_id: 6,
2735 flags: 2, // to disable
2736 cltv_expiry_delta: 0,
2737 htlc_minimum_msat: 0,
2738 htlc_maximum_msat: OptionalField::Absent,
2740 fee_proportional_millionths: 0,
2741 excess_data: Vec::new()
2743 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2744 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2745 short_channel_id: 7,
2747 flags: 2, // to disable
2748 cltv_expiry_delta: 0,
2749 htlc_minimum_msat: 0,
2750 htlc_maximum_msat: OptionalField::Absent,
2752 fee_proportional_millionths: 0,
2753 excess_data: Vec::new()
2756 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2757 assert_eq!(route.paths[0].len(), 4);
2759 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2760 assert_eq!(route.paths[0][0].short_channel_id, 2);
2761 assert_eq!(route.paths[0][0].fee_msat, 200);
2762 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2763 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2764 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2766 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2767 assert_eq!(route.paths[0][1].short_channel_id, 4);
2768 assert_eq!(route.paths[0][1].fee_msat, 100);
2769 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2770 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2771 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2773 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2774 assert_eq!(route.paths[0][2].short_channel_id, 5);
2775 assert_eq!(route.paths[0][2].fee_msat, 0);
2776 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2777 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2778 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new());
2780 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2781 assert_eq!(route.paths[0][3].short_channel_id, 8);
2782 assert_eq!(route.paths[0][3].fee_msat, 100);
2783 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2784 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2785 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2788 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2789 let zero_fees = RoutingFees {
2791 proportional_millionths: 0,
2793 vec![RouteHint(vec![RouteHintHop {
2794 src_node_id: nodes[4],
2795 short_channel_id: 11,
2797 cltv_expiry_delta: (11 << 4) | 1,
2798 htlc_minimum_msat: None,
2799 htlc_maximum_msat: None,
2801 src_node_id: nodes[3],
2802 short_channel_id: 8,
2804 cltv_expiry_delta: (8 << 4) | 1,
2805 htlc_minimum_msat: None,
2806 htlc_maximum_msat: None,
2807 }]), RouteHint(vec![RouteHintHop {
2808 src_node_id: nodes[4],
2809 short_channel_id: 9,
2812 proportional_millionths: 0,
2814 cltv_expiry_delta: (9 << 4) | 1,
2815 htlc_minimum_msat: None,
2816 htlc_maximum_msat: None,
2817 }]), RouteHint(vec![RouteHintHop {
2818 src_node_id: nodes[5],
2819 short_channel_id: 10,
2821 cltv_expiry_delta: (10 << 4) | 1,
2822 htlc_minimum_msat: None,
2823 htlc_maximum_msat: None,
2828 fn last_hops_with_public_channel_test() {
2829 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2830 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2831 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
2832 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2833 // This test shows that public routes can be present in the invoice
2834 // which would be handled in the same manner.
2836 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2837 assert_eq!(route.paths[0].len(), 5);
2839 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2840 assert_eq!(route.paths[0][0].short_channel_id, 2);
2841 assert_eq!(route.paths[0][0].fee_msat, 100);
2842 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2843 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2844 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2846 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2847 assert_eq!(route.paths[0][1].short_channel_id, 4);
2848 assert_eq!(route.paths[0][1].fee_msat, 0);
2849 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2850 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2851 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2853 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2854 assert_eq!(route.paths[0][2].short_channel_id, 6);
2855 assert_eq!(route.paths[0][2].fee_msat, 0);
2856 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2857 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2858 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2860 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2861 assert_eq!(route.paths[0][3].short_channel_id, 11);
2862 assert_eq!(route.paths[0][3].fee_msat, 0);
2863 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2864 // If we have a peer in the node map, we'll use their features here since we don't have
2865 // a way of figuring out their features from the invoice:
2866 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2867 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2869 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2870 assert_eq!(route.paths[0][4].short_channel_id, 8);
2871 assert_eq!(route.paths[0][4].fee_msat, 100);
2872 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2873 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2874 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2878 fn our_chans_last_hop_connect_test() {
2879 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2880 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2881 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
2883 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
2884 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2885 let mut last_hops = last_hops(&nodes);
2886 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2887 let route = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer).unwrap();
2888 assert_eq!(route.paths[0].len(), 2);
2890 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
2891 assert_eq!(route.paths[0][0].short_channel_id, 42);
2892 assert_eq!(route.paths[0][0].fee_msat, 0);
2893 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
2894 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2895 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2897 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
2898 assert_eq!(route.paths[0][1].short_channel_id, 8);
2899 assert_eq!(route.paths[0][1].fee_msat, 100);
2900 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2901 assert_eq!(route.paths[0][1].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2902 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2904 last_hops[0].0[0].fees.base_msat = 1000;
2906 // Revert to via 6 as the fee on 8 goes up
2907 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops);
2908 let route = get_route(&our_id, &payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
2909 assert_eq!(route.paths[0].len(), 4);
2911 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2912 assert_eq!(route.paths[0][0].short_channel_id, 2);
2913 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
2914 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2915 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2916 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2918 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2919 assert_eq!(route.paths[0][1].short_channel_id, 4);
2920 assert_eq!(route.paths[0][1].fee_msat, 100);
2921 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
2922 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2923 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2925 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
2926 assert_eq!(route.paths[0][2].short_channel_id, 7);
2927 assert_eq!(route.paths[0][2].fee_msat, 0);
2928 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
2929 // If we have a peer in the node map, we'll use their features here since we don't have
2930 // a way of figuring out their features from the invoice:
2931 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
2932 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
2934 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2935 assert_eq!(route.paths[0][3].short_channel_id, 10);
2936 assert_eq!(route.paths[0][3].fee_msat, 100);
2937 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2938 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2939 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2941 // ...but still use 8 for larger payments as 6 has a variable feerate
2942 let route = get_route(&our_id, &payee, &network_graph, None, 2000, 42, Arc::clone(&logger), &scorer).unwrap();
2943 assert_eq!(route.paths[0].len(), 5);
2945 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2946 assert_eq!(route.paths[0][0].short_channel_id, 2);
2947 assert_eq!(route.paths[0][0].fee_msat, 3000);
2948 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2949 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2950 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2952 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2953 assert_eq!(route.paths[0][1].short_channel_id, 4);
2954 assert_eq!(route.paths[0][1].fee_msat, 0);
2955 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2956 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2957 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2959 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2960 assert_eq!(route.paths[0][2].short_channel_id, 6);
2961 assert_eq!(route.paths[0][2].fee_msat, 0);
2962 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2963 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2964 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2966 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2967 assert_eq!(route.paths[0][3].short_channel_id, 11);
2968 assert_eq!(route.paths[0][3].fee_msat, 1000);
2969 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2970 // If we have a peer in the node map, we'll use their features here since we don't have
2971 // a way of figuring out their features from the invoice:
2972 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2973 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2975 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2976 assert_eq!(route.paths[0][4].short_channel_id, 8);
2977 assert_eq!(route.paths[0][4].fee_msat, 2000);
2978 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2979 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2980 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2983 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> {
2984 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
2985 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
2986 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
2988 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
2989 let last_hops = RouteHint(vec![RouteHintHop {
2990 src_node_id: middle_node_id,
2991 short_channel_id: 8,
2994 proportional_millionths: last_hop_fee_prop,
2996 cltv_expiry_delta: (8 << 4) | 1,
2997 htlc_minimum_msat: None,
2998 htlc_maximum_msat: last_hop_htlc_max,
3000 let payee = Payee::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3001 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3002 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3003 get_route(&source_node_id, &payee, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()), Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer)
3007 fn unannounced_path_test() {
3008 // We should be able to send a payment to a destination without any help of a routing graph
3009 // if we have a channel with a common counterparty that appears in the first and last hop
3011 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3013 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3014 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3015 assert_eq!(route.paths[0].len(), 2);
3017 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3018 assert_eq!(route.paths[0][0].short_channel_id, 42);
3019 assert_eq!(route.paths[0][0].fee_msat, 1001);
3020 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3021 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3022 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3024 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3025 assert_eq!(route.paths[0][1].short_channel_id, 8);
3026 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3027 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3028 assert_eq!(route.paths[0][1].node_features.le_flags(), &[0; 0]); // We dont pass flags in from invoices yet
3029 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3033 fn overflow_unannounced_path_test_liquidity_underflow() {
3034 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3035 // the last-hop had a fee which overflowed a u64, we'd panic.
3036 // This was due to us adding the first-hop from us unconditionally, causing us to think
3037 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3038 // In this test, we previously hit a subtraction underflow due to having less available
3039 // liquidity at the last hop than 0.
3040 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());
3044 fn overflow_unannounced_path_test_feerate_overflow() {
3045 // This tests for the same case as above, except instead of hitting a subtraction
3046 // underflow, we hit a case where the fee charged at a hop overflowed.
3047 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());
3051 fn available_amount_while_routing_test() {
3052 // Tests whether we choose the correct available channel amount while routing.
3054 let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
3055 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3056 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3057 let payee = Payee::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3059 // We will use a simple single-path route from
3060 // our node to node2 via node0: channels {1, 3}.
3062 // First disable all other paths.
3063 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3064 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3065 short_channel_id: 2,
3068 cltv_expiry_delta: 0,
3069 htlc_minimum_msat: 0,
3070 htlc_maximum_msat: OptionalField::Present(100_000),
3072 fee_proportional_millionths: 0,
3073 excess_data: Vec::new()
3075 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3076 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3077 short_channel_id: 12,
3080 cltv_expiry_delta: 0,
3081 htlc_minimum_msat: 0,
3082 htlc_maximum_msat: OptionalField::Present(100_000),
3084 fee_proportional_millionths: 0,
3085 excess_data: Vec::new()
3088 // Make the first channel (#1) very permissive,
3089 // and we will be testing all limits on the second channel.
3090 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3091 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3092 short_channel_id: 1,
3095 cltv_expiry_delta: 0,
3096 htlc_minimum_msat: 0,
3097 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3099 fee_proportional_millionths: 0,
3100 excess_data: Vec::new()
3103 // First, let's see if routing works if we have absolutely no idea about the available amount.
3104 // In this case, it should be set to 250_000 sats.
3105 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3106 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3107 short_channel_id: 3,
3110 cltv_expiry_delta: 0,
3111 htlc_minimum_msat: 0,
3112 htlc_maximum_msat: OptionalField::Absent,
3114 fee_proportional_millionths: 0,
3115 excess_data: Vec::new()
3119 // Attempt to route more than available results in a failure.
3120 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3121 &our_id, &payee, &network_graph, None, 250_000_001, 42, Arc::clone(&logger), &scorer) {
3122 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3123 } else { panic!(); }
3127 // Now, attempt to route an exact amount we have should be fine.
3128 let route = get_route(&our_id, &payee, &network_graph, None, 250_000_000, 42, Arc::clone(&logger), &scorer).unwrap();
3129 assert_eq!(route.paths.len(), 1);
3130 let path = route.paths.last().unwrap();
3131 assert_eq!(path.len(), 2);
3132 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3133 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3136 // Check that setting outbound_capacity_msat in first_hops limits the channels.
3137 // Disable channel #1 and use another first hop.
3138 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3139 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3140 short_channel_id: 1,
3143 cltv_expiry_delta: 0,
3144 htlc_minimum_msat: 0,
3145 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3147 fee_proportional_millionths: 0,
3148 excess_data: Vec::new()
3151 // Now, limit the first_hop by the outbound_capacity_msat of 200_000 sats.
3152 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3155 // Attempt to route more than available results in a failure.
3156 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3157 &our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_001, 42, Arc::clone(&logger), &scorer) {
3158 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3159 } else { panic!(); }
3163 // Now, attempt to route an exact amount we have should be fine.
3164 let route = get_route(&our_id, &payee, &network_graph, Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_000, 42, Arc::clone(&logger), &scorer).unwrap();
3165 assert_eq!(route.paths.len(), 1);
3166 let path = route.paths.last().unwrap();
3167 assert_eq!(path.len(), 2);
3168 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3169 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3172 // Enable channel #1 back.
3173 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3174 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3175 short_channel_id: 1,
3178 cltv_expiry_delta: 0,
3179 htlc_minimum_msat: 0,
3180 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3182 fee_proportional_millionths: 0,
3183 excess_data: Vec::new()
3187 // Now let's see if routing works if we know only htlc_maximum_msat.
3188 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3189 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3190 short_channel_id: 3,
3193 cltv_expiry_delta: 0,
3194 htlc_minimum_msat: 0,
3195 htlc_maximum_msat: OptionalField::Present(15_000),
3197 fee_proportional_millionths: 0,
3198 excess_data: Vec::new()
3202 // Attempt to route more than available results in a failure.
3203 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3204 &our_id, &payee, &network_graph, None, 15_001, 42, Arc::clone(&logger), &scorer) {
3205 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3206 } else { panic!(); }
3210 // Now, attempt to route an exact amount we have should be fine.
3211 let route = get_route(&our_id, &payee, &network_graph, None, 15_000, 42, Arc::clone(&logger), &scorer).unwrap();
3212 assert_eq!(route.paths.len(), 1);
3213 let path = route.paths.last().unwrap();
3214 assert_eq!(path.len(), 2);
3215 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3216 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3219 // Now let's see if routing works if we know only capacity from the UTXO.
3221 // We can't change UTXO capacity on the fly, so we'll disable
3222 // the existing channel and add another one with the capacity we need.
3223 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3224 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3225 short_channel_id: 3,
3228 cltv_expiry_delta: 0,
3229 htlc_minimum_msat: 0,
3230 htlc_maximum_msat: OptionalField::Absent,
3232 fee_proportional_millionths: 0,
3233 excess_data: Vec::new()
3236 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3237 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3238 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3239 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3240 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3242 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3243 net_graph_msg_handler.add_chain_access(Some(chain_monitor));
3245 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3246 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3247 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3248 short_channel_id: 333,
3251 cltv_expiry_delta: (3 << 4) | 1,
3252 htlc_minimum_msat: 0,
3253 htlc_maximum_msat: OptionalField::Absent,
3255 fee_proportional_millionths: 0,
3256 excess_data: Vec::new()
3258 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3259 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3260 short_channel_id: 333,
3263 cltv_expiry_delta: (3 << 4) | 2,
3264 htlc_minimum_msat: 0,
3265 htlc_maximum_msat: OptionalField::Absent,
3267 fee_proportional_millionths: 0,
3268 excess_data: Vec::new()
3272 // Attempt to route more than available results in a failure.
3273 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3274 &our_id, &payee, &network_graph, None, 15_001, 42, Arc::clone(&logger), &scorer) {
3275 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3276 } else { panic!(); }
3280 // Now, attempt to route an exact amount we have should be fine.
3281 let route = get_route(&our_id, &payee, &network_graph, None, 15_000, 42, Arc::clone(&logger), &scorer).unwrap();
3282 assert_eq!(route.paths.len(), 1);
3283 let path = route.paths.last().unwrap();
3284 assert_eq!(path.len(), 2);
3285 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3286 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3289 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3290 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3291 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3292 short_channel_id: 333,
3295 cltv_expiry_delta: 0,
3296 htlc_minimum_msat: 0,
3297 htlc_maximum_msat: OptionalField::Present(10_000),
3299 fee_proportional_millionths: 0,
3300 excess_data: Vec::new()
3304 // Attempt to route more than available results in a failure.
3305 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3306 &our_id, &payee, &network_graph, None, 10_001, 42, Arc::clone(&logger), &scorer) {
3307 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3308 } else { panic!(); }
3312 // Now, attempt to route an exact amount we have should be fine.
3313 let route = get_route(&our_id, &payee, &network_graph, None, 10_000, 42, Arc::clone(&logger), &scorer).unwrap();
3314 assert_eq!(route.paths.len(), 1);
3315 let path = route.paths.last().unwrap();
3316 assert_eq!(path.len(), 2);
3317 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3318 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3323 fn available_liquidity_last_hop_test() {
3324 // Check that available liquidity properly limits the path even when only
3325 // one of the latter hops is limited.
3326 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3327 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3328 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3329 let payee = Payee::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3331 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3332 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3333 // Total capacity: 50 sats.
3335 // Disable other potential paths.
3336 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3337 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3338 short_channel_id: 2,
3341 cltv_expiry_delta: 0,
3342 htlc_minimum_msat: 0,
3343 htlc_maximum_msat: OptionalField::Present(100_000),
3345 fee_proportional_millionths: 0,
3346 excess_data: Vec::new()
3348 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3349 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3350 short_channel_id: 7,
3353 cltv_expiry_delta: 0,
3354 htlc_minimum_msat: 0,
3355 htlc_maximum_msat: OptionalField::Present(100_000),
3357 fee_proportional_millionths: 0,
3358 excess_data: Vec::new()
3363 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3364 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3365 short_channel_id: 12,
3368 cltv_expiry_delta: 0,
3369 htlc_minimum_msat: 0,
3370 htlc_maximum_msat: OptionalField::Present(100_000),
3372 fee_proportional_millionths: 0,
3373 excess_data: Vec::new()
3375 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3376 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3377 short_channel_id: 13,
3380 cltv_expiry_delta: 0,
3381 htlc_minimum_msat: 0,
3382 htlc_maximum_msat: OptionalField::Present(100_000),
3384 fee_proportional_millionths: 0,
3385 excess_data: Vec::new()
3388 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3389 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3390 short_channel_id: 6,
3393 cltv_expiry_delta: 0,
3394 htlc_minimum_msat: 0,
3395 htlc_maximum_msat: OptionalField::Present(50_000),
3397 fee_proportional_millionths: 0,
3398 excess_data: Vec::new()
3400 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3401 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3402 short_channel_id: 11,
3405 cltv_expiry_delta: 0,
3406 htlc_minimum_msat: 0,
3407 htlc_maximum_msat: OptionalField::Present(100_000),
3409 fee_proportional_millionths: 0,
3410 excess_data: Vec::new()
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, &payee, &network_graph, None, 60_000, 42, Arc::clone(&logger), &scorer) {
3416 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3417 } else { panic!(); }
3421 // Now, attempt to route 49 sats (just a bit below the capacity).
3422 let route = get_route(&our_id, &payee, &network_graph, None, 49_000, 42, Arc::clone(&logger), &scorer).unwrap();
3423 assert_eq!(route.paths.len(), 1);
3424 let mut total_amount_paid_msat = 0;
3425 for path in &route.paths {
3426 assert_eq!(path.len(), 4);
3427 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3428 total_amount_paid_msat += path.last().unwrap().fee_msat;
3430 assert_eq!(total_amount_paid_msat, 49_000);
3434 // Attempt to route an exact amount is also fine
3435 let route = get_route(&our_id, &payee, &network_graph, None, 50_000, 42, Arc::clone(&logger), &scorer).unwrap();
3436 assert_eq!(route.paths.len(), 1);
3437 let mut total_amount_paid_msat = 0;
3438 for path in &route.paths {
3439 assert_eq!(path.len(), 4);
3440 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3441 total_amount_paid_msat += path.last().unwrap().fee_msat;
3443 assert_eq!(total_amount_paid_msat, 50_000);
3448 fn ignore_fee_first_hop_test() {
3449 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3450 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3451 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3452 let payee = Payee::from_node_id(nodes[2]);
3454 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3455 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3456 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3457 short_channel_id: 1,
3460 cltv_expiry_delta: 0,
3461 htlc_minimum_msat: 0,
3462 htlc_maximum_msat: OptionalField::Present(100_000),
3463 fee_base_msat: 1_000_000,
3464 fee_proportional_millionths: 0,
3465 excess_data: Vec::new()
3467 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3468 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3469 short_channel_id: 3,
3472 cltv_expiry_delta: 0,
3473 htlc_minimum_msat: 0,
3474 htlc_maximum_msat: OptionalField::Present(50_000),
3476 fee_proportional_millionths: 0,
3477 excess_data: Vec::new()
3481 let route = get_route(&our_id, &payee, &network_graph, None, 50_000, 42, Arc::clone(&logger), &scorer).unwrap();
3482 assert_eq!(route.paths.len(), 1);
3483 let mut total_amount_paid_msat = 0;
3484 for path in &route.paths {
3485 assert_eq!(path.len(), 2);
3486 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3487 total_amount_paid_msat += path.last().unwrap().fee_msat;
3489 assert_eq!(total_amount_paid_msat, 50_000);
3494 fn simple_mpp_route_test() {
3495 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3496 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3497 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3498 let payee = Payee::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3500 // We need a route consisting of 3 paths:
3501 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3502 // To achieve this, the amount being transferred should be around
3503 // the total capacity of these 3 paths.
3505 // First, we set limits on these (previously unlimited) channels.
3506 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3508 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3509 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3510 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3511 short_channel_id: 1,
3514 cltv_expiry_delta: 0,
3515 htlc_minimum_msat: 0,
3516 htlc_maximum_msat: OptionalField::Present(100_000),
3518 fee_proportional_millionths: 0,
3519 excess_data: Vec::new()
3521 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3522 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3523 short_channel_id: 3,
3526 cltv_expiry_delta: 0,
3527 htlc_minimum_msat: 0,
3528 htlc_maximum_msat: OptionalField::Present(50_000),
3530 fee_proportional_millionths: 0,
3531 excess_data: Vec::new()
3534 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3535 // (total limit 60).
3536 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3537 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3538 short_channel_id: 12,
3541 cltv_expiry_delta: 0,
3542 htlc_minimum_msat: 0,
3543 htlc_maximum_msat: OptionalField::Present(60_000),
3545 fee_proportional_millionths: 0,
3546 excess_data: Vec::new()
3548 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3549 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3550 short_channel_id: 13,
3553 cltv_expiry_delta: 0,
3554 htlc_minimum_msat: 0,
3555 htlc_maximum_msat: OptionalField::Present(60_000),
3557 fee_proportional_millionths: 0,
3558 excess_data: Vec::new()
3561 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3562 // (total capacity 180 sats).
3563 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3564 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3565 short_channel_id: 2,
3568 cltv_expiry_delta: 0,
3569 htlc_minimum_msat: 0,
3570 htlc_maximum_msat: OptionalField::Present(200_000),
3572 fee_proportional_millionths: 0,
3573 excess_data: Vec::new()
3575 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3577 short_channel_id: 4,
3580 cltv_expiry_delta: 0,
3581 htlc_minimum_msat: 0,
3582 htlc_maximum_msat: OptionalField::Present(180_000),
3584 fee_proportional_millionths: 0,
3585 excess_data: Vec::new()
3589 // Attempt to route more than available results in a failure.
3590 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3591 &our_id, &payee, &network_graph, None, 300_000, 42, Arc::clone(&logger), &scorer) {
3592 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3593 } else { panic!(); }
3597 // Now, attempt to route 250 sats (just a bit below the capacity).
3598 // Our algorithm should provide us with these 3 paths.
3599 let route = get_route(&our_id, &payee, &network_graph, None, 250_000, 42, Arc::clone(&logger), &scorer).unwrap();
3600 assert_eq!(route.paths.len(), 3);
3601 let mut total_amount_paid_msat = 0;
3602 for path in &route.paths {
3603 assert_eq!(path.len(), 2);
3604 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3605 total_amount_paid_msat += path.last().unwrap().fee_msat;
3607 assert_eq!(total_amount_paid_msat, 250_000);
3611 // Attempt to route an exact amount is also fine
3612 let route = get_route(&our_id, &payee, &network_graph, None, 290_000, 42, Arc::clone(&logger), &scorer).unwrap();
3613 assert_eq!(route.paths.len(), 3);
3614 let mut total_amount_paid_msat = 0;
3615 for path in &route.paths {
3616 assert_eq!(path.len(), 2);
3617 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3618 total_amount_paid_msat += path.last().unwrap().fee_msat;
3620 assert_eq!(total_amount_paid_msat, 290_000);
3625 fn long_mpp_route_test() {
3626 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3627 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3628 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3629 let payee = Payee::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3631 // We need a route consisting of 3 paths:
3632 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3633 // Note that these paths overlap (channels 5, 12, 13).
3634 // We will route 300 sats.
3635 // Each path will have 100 sats capacity, those channels which
3636 // are used twice will have 200 sats capacity.
3638 // Disable other potential paths.
3639 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3640 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3641 short_channel_id: 2,
3644 cltv_expiry_delta: 0,
3645 htlc_minimum_msat: 0,
3646 htlc_maximum_msat: OptionalField::Present(100_000),
3648 fee_proportional_millionths: 0,
3649 excess_data: Vec::new()
3651 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3652 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3653 short_channel_id: 7,
3656 cltv_expiry_delta: 0,
3657 htlc_minimum_msat: 0,
3658 htlc_maximum_msat: OptionalField::Present(100_000),
3660 fee_proportional_millionths: 0,
3661 excess_data: Vec::new()
3664 // Path via {node0, node2} is channels {1, 3, 5}.
3665 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3666 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3667 short_channel_id: 1,
3670 cltv_expiry_delta: 0,
3671 htlc_minimum_msat: 0,
3672 htlc_maximum_msat: OptionalField::Present(100_000),
3674 fee_proportional_millionths: 0,
3675 excess_data: Vec::new()
3677 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3678 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3679 short_channel_id: 3,
3682 cltv_expiry_delta: 0,
3683 htlc_minimum_msat: 0,
3684 htlc_maximum_msat: OptionalField::Present(100_000),
3686 fee_proportional_millionths: 0,
3687 excess_data: Vec::new()
3690 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3691 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3692 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3693 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3694 short_channel_id: 5,
3697 cltv_expiry_delta: 0,
3698 htlc_minimum_msat: 0,
3699 htlc_maximum_msat: OptionalField::Present(200_000),
3701 fee_proportional_millionths: 0,
3702 excess_data: Vec::new()
3705 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3706 // Add 100 sats to the capacities of {12, 13}, because these channels
3707 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3708 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3709 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3710 short_channel_id: 12,
3713 cltv_expiry_delta: 0,
3714 htlc_minimum_msat: 0,
3715 htlc_maximum_msat: OptionalField::Present(200_000),
3717 fee_proportional_millionths: 0,
3718 excess_data: Vec::new()
3720 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3721 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3722 short_channel_id: 13,
3725 cltv_expiry_delta: 0,
3726 htlc_minimum_msat: 0,
3727 htlc_maximum_msat: OptionalField::Present(200_000),
3729 fee_proportional_millionths: 0,
3730 excess_data: Vec::new()
3733 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3734 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3735 short_channel_id: 6,
3738 cltv_expiry_delta: 0,
3739 htlc_minimum_msat: 0,
3740 htlc_maximum_msat: OptionalField::Present(100_000),
3742 fee_proportional_millionths: 0,
3743 excess_data: Vec::new()
3745 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3746 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3747 short_channel_id: 11,
3750 cltv_expiry_delta: 0,
3751 htlc_minimum_msat: 0,
3752 htlc_maximum_msat: OptionalField::Present(100_000),
3754 fee_proportional_millionths: 0,
3755 excess_data: Vec::new()
3758 // Path via {node7, node2} is channels {12, 13, 5}.
3759 // We already limited them to 200 sats (they are used twice for 100 sats).
3760 // Nothing to do here.
3763 // Attempt to route more than available results in a failure.
3764 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3765 &our_id, &payee, &network_graph, None, 350_000, 42, Arc::clone(&logger), &scorer) {
3766 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3767 } else { panic!(); }
3771 // Now, attempt to route 300 sats (exact amount we can route).
3772 // Our algorithm should provide us with these 3 paths, 100 sats each.
3773 let route = get_route(&our_id, &payee, &network_graph, None, 300_000, 42, Arc::clone(&logger), &scorer).unwrap();
3774 assert_eq!(route.paths.len(), 3);
3776 let mut total_amount_paid_msat = 0;
3777 for path in &route.paths {
3778 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3779 total_amount_paid_msat += path.last().unwrap().fee_msat;
3781 assert_eq!(total_amount_paid_msat, 300_000);
3787 fn mpp_cheaper_route_test() {
3788 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3789 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3790 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3791 let payee = Payee::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3793 // This test checks that if we have two cheaper paths and one more expensive path,
3794 // so that liquidity-wise any 2 of 3 combination is sufficient,
3795 // two cheaper paths will be taken.
3796 // These paths have equal available liquidity.
3798 // We need a combination of 3 paths:
3799 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3800 // Note that these paths overlap (channels 5, 12, 13).
3801 // Each path will have 100 sats capacity, those channels which
3802 // are used twice will have 200 sats capacity.
3804 // Disable other potential paths.
3805 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3806 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3807 short_channel_id: 2,
3810 cltv_expiry_delta: 0,
3811 htlc_minimum_msat: 0,
3812 htlc_maximum_msat: OptionalField::Present(100_000),
3814 fee_proportional_millionths: 0,
3815 excess_data: Vec::new()
3817 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3818 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3819 short_channel_id: 7,
3822 cltv_expiry_delta: 0,
3823 htlc_minimum_msat: 0,
3824 htlc_maximum_msat: OptionalField::Present(100_000),
3826 fee_proportional_millionths: 0,
3827 excess_data: Vec::new()
3830 // Path via {node0, node2} is channels {1, 3, 5}.
3831 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3832 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3833 short_channel_id: 1,
3836 cltv_expiry_delta: 0,
3837 htlc_minimum_msat: 0,
3838 htlc_maximum_msat: OptionalField::Present(100_000),
3840 fee_proportional_millionths: 0,
3841 excess_data: Vec::new()
3843 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3844 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3845 short_channel_id: 3,
3848 cltv_expiry_delta: 0,
3849 htlc_minimum_msat: 0,
3850 htlc_maximum_msat: OptionalField::Present(100_000),
3852 fee_proportional_millionths: 0,
3853 excess_data: Vec::new()
3856 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3857 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3858 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3860 short_channel_id: 5,
3863 cltv_expiry_delta: 0,
3864 htlc_minimum_msat: 0,
3865 htlc_maximum_msat: OptionalField::Present(200_000),
3867 fee_proportional_millionths: 0,
3868 excess_data: Vec::new()
3871 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3872 // Add 100 sats to the capacities of {12, 13}, because these channels
3873 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3874 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3875 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3876 short_channel_id: 12,
3879 cltv_expiry_delta: 0,
3880 htlc_minimum_msat: 0,
3881 htlc_maximum_msat: OptionalField::Present(200_000),
3883 fee_proportional_millionths: 0,
3884 excess_data: Vec::new()
3886 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3887 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3888 short_channel_id: 13,
3891 cltv_expiry_delta: 0,
3892 htlc_minimum_msat: 0,
3893 htlc_maximum_msat: OptionalField::Present(200_000),
3895 fee_proportional_millionths: 0,
3896 excess_data: Vec::new()
3899 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3900 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3901 short_channel_id: 6,
3904 cltv_expiry_delta: 0,
3905 htlc_minimum_msat: 0,
3906 htlc_maximum_msat: OptionalField::Present(100_000),
3907 fee_base_msat: 1_000,
3908 fee_proportional_millionths: 0,
3909 excess_data: Vec::new()
3911 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3912 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3913 short_channel_id: 11,
3916 cltv_expiry_delta: 0,
3917 htlc_minimum_msat: 0,
3918 htlc_maximum_msat: OptionalField::Present(100_000),
3920 fee_proportional_millionths: 0,
3921 excess_data: Vec::new()
3924 // Path via {node7, node2} is channels {12, 13, 5}.
3925 // We already limited them to 200 sats (they are used twice for 100 sats).
3926 // Nothing to do here.
3929 // Now, attempt to route 180 sats.
3930 // Our algorithm should provide us with these 2 paths.
3931 let route = get_route(&our_id, &payee, &network_graph, None, 180_000, 42, Arc::clone(&logger), &scorer).unwrap();
3932 assert_eq!(route.paths.len(), 2);
3934 let mut total_value_transferred_msat = 0;
3935 let mut total_paid_msat = 0;
3936 for path in &route.paths {
3937 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3938 total_value_transferred_msat += path.last().unwrap().fee_msat;
3940 total_paid_msat += hop.fee_msat;
3943 // If we paid fee, this would be higher.
3944 assert_eq!(total_value_transferred_msat, 180_000);
3945 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
3946 assert_eq!(total_fees_paid, 0);
3951 fn fees_on_mpp_route_test() {
3952 // This test makes sure that MPP algorithm properly takes into account
3953 // fees charged on the channels, by making the fees impactful:
3954 // if the fee is not properly accounted for, the behavior is different.
3955 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3956 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3957 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
3958 let payee = Payee::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3960 // We need a route consisting of 2 paths:
3961 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
3962 // We will route 200 sats, Each path will have 100 sats capacity.
3964 // This test is not particularly stable: e.g.,
3965 // there's a way to route via {node0, node2, node4}.
3966 // It works while pathfinding is deterministic, but can be broken otherwise.
3967 // It's fine to ignore this concern for now.
3969 // Disable other potential paths.
3970 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3971 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3972 short_channel_id: 2,
3975 cltv_expiry_delta: 0,
3976 htlc_minimum_msat: 0,
3977 htlc_maximum_msat: OptionalField::Present(100_000),
3979 fee_proportional_millionths: 0,
3980 excess_data: Vec::new()
3983 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3984 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3985 short_channel_id: 7,
3988 cltv_expiry_delta: 0,
3989 htlc_minimum_msat: 0,
3990 htlc_maximum_msat: OptionalField::Present(100_000),
3992 fee_proportional_millionths: 0,
3993 excess_data: Vec::new()
3996 // Path via {node0, node2} is channels {1, 3, 5}.
3997 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3998 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3999 short_channel_id: 1,
4002 cltv_expiry_delta: 0,
4003 htlc_minimum_msat: 0,
4004 htlc_maximum_msat: OptionalField::Present(100_000),
4006 fee_proportional_millionths: 0,
4007 excess_data: Vec::new()
4009 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4010 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4011 short_channel_id: 3,
4014 cltv_expiry_delta: 0,
4015 htlc_minimum_msat: 0,
4016 htlc_maximum_msat: OptionalField::Present(100_000),
4018 fee_proportional_millionths: 0,
4019 excess_data: Vec::new()
4022 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4023 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4024 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4025 short_channel_id: 5,
4028 cltv_expiry_delta: 0,
4029 htlc_minimum_msat: 0,
4030 htlc_maximum_msat: OptionalField::Present(100_000),
4032 fee_proportional_millionths: 0,
4033 excess_data: Vec::new()
4036 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4037 // All channels should be 100 sats capacity. But for the fee experiment,
4038 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4039 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4040 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4041 // so no matter how large are other channels,
4042 // the whole path will be limited by 100 sats with just these 2 conditions:
4043 // - channel 12 capacity is 250 sats
4044 // - fee for channel 6 is 150 sats
4045 // Let's test this by enforcing these 2 conditions and removing other limits.
4046 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4047 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4048 short_channel_id: 12,
4051 cltv_expiry_delta: 0,
4052 htlc_minimum_msat: 0,
4053 htlc_maximum_msat: OptionalField::Present(250_000),
4055 fee_proportional_millionths: 0,
4056 excess_data: Vec::new()
4058 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4059 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4060 short_channel_id: 13,
4063 cltv_expiry_delta: 0,
4064 htlc_minimum_msat: 0,
4065 htlc_maximum_msat: OptionalField::Absent,
4067 fee_proportional_millionths: 0,
4068 excess_data: Vec::new()
4071 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4072 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4073 short_channel_id: 6,
4076 cltv_expiry_delta: 0,
4077 htlc_minimum_msat: 0,
4078 htlc_maximum_msat: OptionalField::Absent,
4079 fee_base_msat: 150_000,
4080 fee_proportional_millionths: 0,
4081 excess_data: Vec::new()
4083 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4084 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4085 short_channel_id: 11,
4088 cltv_expiry_delta: 0,
4089 htlc_minimum_msat: 0,
4090 htlc_maximum_msat: OptionalField::Absent,
4092 fee_proportional_millionths: 0,
4093 excess_data: Vec::new()
4097 // Attempt to route more than available results in a failure.
4098 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4099 &our_id, &payee, &network_graph, None, 210_000, 42, Arc::clone(&logger), &scorer) {
4100 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4101 } else { panic!(); }
4105 // Now, attempt to route 200 sats (exact amount we can route).
4106 let route = get_route(&our_id, &payee, &network_graph, None, 200_000, 42, Arc::clone(&logger), &scorer).unwrap();
4107 assert_eq!(route.paths.len(), 2);
4109 let mut total_amount_paid_msat = 0;
4110 for path in &route.paths {
4111 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4112 total_amount_paid_msat += path.last().unwrap().fee_msat;
4114 assert_eq!(total_amount_paid_msat, 200_000);
4115 assert_eq!(route.get_total_fees(), 150_000);
4120 fn mpp_with_last_hops() {
4121 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4122 // via a single last-hop route hint, we'd fail to route if we first collected routes
4123 // totaling close but not quite enough to fund the full payment.
4125 // This was because we considered last-hop hints to have exactly the sought payment amount
4126 // instead of the amount we were trying to collect, needlessly limiting our path searching
4127 // at the very first hop.
4129 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4130 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4131 // to only have the remaining to-collect amount in available liquidity.
4133 // This bug appeared in production in some specific channel configurations.
4134 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4135 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4136 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4137 let payee = Payee::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4138 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4139 src_node_id: nodes[2],
4140 short_channel_id: 42,
4141 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4142 cltv_expiry_delta: 42,
4143 htlc_minimum_msat: None,
4144 htlc_maximum_msat: None,
4147 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4148 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4149 // would first use the no-fee route and then fail to find a path along the second route as
4150 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4151 // under 5% of our payment amount.
4152 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4153 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4154 short_channel_id: 1,
4157 cltv_expiry_delta: (5 << 4) | 5,
4158 htlc_minimum_msat: 0,
4159 htlc_maximum_msat: OptionalField::Present(99_000),
4160 fee_base_msat: u32::max_value(),
4161 fee_proportional_millionths: u32::max_value(),
4162 excess_data: Vec::new()
4164 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4165 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4166 short_channel_id: 2,
4169 cltv_expiry_delta: (5 << 4) | 3,
4170 htlc_minimum_msat: 0,
4171 htlc_maximum_msat: OptionalField::Present(99_000),
4172 fee_base_msat: u32::max_value(),
4173 fee_proportional_millionths: u32::max_value(),
4174 excess_data: Vec::new()
4176 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4177 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4178 short_channel_id: 4,
4181 cltv_expiry_delta: (4 << 4) | 1,
4182 htlc_minimum_msat: 0,
4183 htlc_maximum_msat: OptionalField::Absent,
4185 fee_proportional_millionths: 0,
4186 excess_data: Vec::new()
4188 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4189 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4190 short_channel_id: 13,
4192 flags: 0|2, // Channel disabled
4193 cltv_expiry_delta: (13 << 4) | 1,
4194 htlc_minimum_msat: 0,
4195 htlc_maximum_msat: OptionalField::Absent,
4197 fee_proportional_millionths: 2000000,
4198 excess_data: Vec::new()
4201 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4203 let route = get_route(&our_id, &payee, &network_graph, None, 100_000, 42, Arc::clone(&logger), &scorer).unwrap();
4204 assert_eq!(route.paths.len(), 2);
4205 // Paths are somewhat randomly ordered, but:
4206 // * the first is channel 2 (1 msat fee) -> channel 4 -> channel 42
4207 // * the second is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4208 assert_eq!(route.paths[0][0].short_channel_id, 2);
4209 assert_eq!(route.paths[0][0].fee_msat, 1);
4210 assert_eq!(route.paths[0][2].fee_msat, 1_000);
4211 assert_eq!(route.paths[1][0].short_channel_id, 1);
4212 assert_eq!(route.paths[1][0].fee_msat, 0);
4213 assert_eq!(route.paths[1][2].fee_msat, 99_000);
4214 assert_eq!(route.get_total_fees(), 1);
4215 assert_eq!(route.get_total_amount(), 100_000);
4219 fn drop_lowest_channel_mpp_route_test() {
4220 // This test checks that low-capacity channel is dropped when after
4221 // path finding we realize that we found more capacity than we need.
4222 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4223 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4224 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4225 let payee = Payee::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4227 // We need a route consisting of 3 paths:
4228 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4230 // The first and the second paths should be sufficient, but the third should be
4231 // cheaper, so that we select it but drop later.
4233 // First, we set limits on these (previously unlimited) channels.
4234 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4236 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4237 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4238 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4239 short_channel_id: 1,
4242 cltv_expiry_delta: 0,
4243 htlc_minimum_msat: 0,
4244 htlc_maximum_msat: OptionalField::Present(100_000),
4246 fee_proportional_millionths: 0,
4247 excess_data: Vec::new()
4249 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4250 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4251 short_channel_id: 3,
4254 cltv_expiry_delta: 0,
4255 htlc_minimum_msat: 0,
4256 htlc_maximum_msat: OptionalField::Present(50_000),
4258 fee_proportional_millionths: 0,
4259 excess_data: Vec::new()
4262 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4263 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4265 short_channel_id: 12,
4268 cltv_expiry_delta: 0,
4269 htlc_minimum_msat: 0,
4270 htlc_maximum_msat: OptionalField::Present(60_000),
4272 fee_proportional_millionths: 0,
4273 excess_data: Vec::new()
4275 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4276 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4277 short_channel_id: 13,
4280 cltv_expiry_delta: 0,
4281 htlc_minimum_msat: 0,
4282 htlc_maximum_msat: OptionalField::Present(60_000),
4284 fee_proportional_millionths: 0,
4285 excess_data: Vec::new()
4288 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4289 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4290 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4291 short_channel_id: 2,
4294 cltv_expiry_delta: 0,
4295 htlc_minimum_msat: 0,
4296 htlc_maximum_msat: OptionalField::Present(20_000),
4298 fee_proportional_millionths: 0,
4299 excess_data: Vec::new()
4301 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4303 short_channel_id: 4,
4306 cltv_expiry_delta: 0,
4307 htlc_minimum_msat: 0,
4308 htlc_maximum_msat: OptionalField::Present(20_000),
4310 fee_proportional_millionths: 0,
4311 excess_data: Vec::new()
4315 // Attempt to route more than available results in a failure.
4316 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4317 &our_id, &payee, &network_graph, None, 150_000, 42, Arc::clone(&logger), &scorer) {
4318 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4319 } else { panic!(); }
4323 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4324 // Our algorithm should provide us with these 3 paths.
4325 let route = get_route(&our_id, &payee, &network_graph, None, 125_000, 42, Arc::clone(&logger), &scorer).unwrap();
4326 assert_eq!(route.paths.len(), 3);
4327 let mut total_amount_paid_msat = 0;
4328 for path in &route.paths {
4329 assert_eq!(path.len(), 2);
4330 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4331 total_amount_paid_msat += path.last().unwrap().fee_msat;
4333 assert_eq!(total_amount_paid_msat, 125_000);
4337 // Attempt to route without the last small cheap channel
4338 let route = get_route(&our_id, &payee, &network_graph, None, 90_000, 42, Arc::clone(&logger), &scorer).unwrap();
4339 assert_eq!(route.paths.len(), 2);
4340 let mut total_amount_paid_msat = 0;
4341 for path in &route.paths {
4342 assert_eq!(path.len(), 2);
4343 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4344 total_amount_paid_msat += path.last().unwrap().fee_msat;
4346 assert_eq!(total_amount_paid_msat, 90_000);
4351 fn min_criteria_consistency() {
4352 // Test that we don't use an inconsistent metric between updating and walking nodes during
4353 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4354 // was updated with a different criterion from the heap sorting, resulting in loops in
4355 // calculated paths. We test for that specific case here.
4357 // We construct a network that looks like this:
4359 // node2 -1(3)2- node3
4363 // node1 -1(5)2- node4 -1(1)2- node6
4369 // We create a loop on the side of our real path - our destination is node 6, with a
4370 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4371 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4372 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4373 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4374 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4375 // "previous hop" being set to node 3, creating a loop in the path.
4376 let secp_ctx = Secp256k1::new();
4377 let logger = Arc::new(test_utils::TestLogger::new());
4378 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
4379 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
4380 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4381 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4382 let payee = Payee::from_node_id(nodes[6]);
4384 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4385 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4386 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4387 short_channel_id: 6,
4390 cltv_expiry_delta: (6 << 4) | 0,
4391 htlc_minimum_msat: 0,
4392 htlc_maximum_msat: OptionalField::Absent,
4394 fee_proportional_millionths: 0,
4395 excess_data: Vec::new()
4397 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4399 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4400 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4401 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4402 short_channel_id: 5,
4405 cltv_expiry_delta: (5 << 4) | 0,
4406 htlc_minimum_msat: 0,
4407 htlc_maximum_msat: OptionalField::Absent,
4409 fee_proportional_millionths: 0,
4410 excess_data: Vec::new()
4412 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4414 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4415 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4416 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4417 short_channel_id: 4,
4420 cltv_expiry_delta: (4 << 4) | 0,
4421 htlc_minimum_msat: 0,
4422 htlc_maximum_msat: OptionalField::Absent,
4424 fee_proportional_millionths: 0,
4425 excess_data: Vec::new()
4427 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4429 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4430 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4431 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4432 short_channel_id: 3,
4435 cltv_expiry_delta: (3 << 4) | 0,
4436 htlc_minimum_msat: 0,
4437 htlc_maximum_msat: OptionalField::Absent,
4439 fee_proportional_millionths: 0,
4440 excess_data: Vec::new()
4442 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4444 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4445 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4446 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4447 short_channel_id: 2,
4450 cltv_expiry_delta: (2 << 4) | 0,
4451 htlc_minimum_msat: 0,
4452 htlc_maximum_msat: OptionalField::Absent,
4454 fee_proportional_millionths: 0,
4455 excess_data: Vec::new()
4458 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4459 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4460 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4461 short_channel_id: 1,
4464 cltv_expiry_delta: (1 << 4) | 0,
4465 htlc_minimum_msat: 100,
4466 htlc_maximum_msat: OptionalField::Absent,
4468 fee_proportional_millionths: 0,
4469 excess_data: Vec::new()
4471 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4474 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4475 let route = get_route(&our_id, &payee, &network_graph, None, 10_000, 42, Arc::clone(&logger), &scorer).unwrap();
4476 assert_eq!(route.paths.len(), 1);
4477 assert_eq!(route.paths[0].len(), 3);
4479 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4480 assert_eq!(route.paths[0][0].short_channel_id, 6);
4481 assert_eq!(route.paths[0][0].fee_msat, 100);
4482 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4483 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4484 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4486 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4487 assert_eq!(route.paths[0][1].short_channel_id, 5);
4488 assert_eq!(route.paths[0][1].fee_msat, 0);
4489 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4490 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4491 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4493 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4494 assert_eq!(route.paths[0][2].short_channel_id, 1);
4495 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4496 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4497 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4498 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4504 fn exact_fee_liquidity_limit() {
4505 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4506 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4507 // we calculated fees on a higher value, resulting in us ignoring such paths.
4508 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4509 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4510 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4511 let payee = Payee::from_node_id(nodes[2]);
4513 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4515 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4516 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4517 short_channel_id: 2,
4520 cltv_expiry_delta: 0,
4521 htlc_minimum_msat: 0,
4522 htlc_maximum_msat: OptionalField::Present(85_000),
4524 fee_proportional_millionths: 0,
4525 excess_data: Vec::new()
4528 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4530 short_channel_id: 12,
4533 cltv_expiry_delta: (4 << 4) | 1,
4534 htlc_minimum_msat: 0,
4535 htlc_maximum_msat: OptionalField::Present(270_000),
4537 fee_proportional_millionths: 1000000,
4538 excess_data: Vec::new()
4542 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4543 // 200% fee charged channel 13 in the 1-to-2 direction.
4544 let route = get_route(&our_id, &payee, &network_graph, None, 90_000, 42, Arc::clone(&logger), &scorer).unwrap();
4545 assert_eq!(route.paths.len(), 1);
4546 assert_eq!(route.paths[0].len(), 2);
4548 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4549 assert_eq!(route.paths[0][0].short_channel_id, 12);
4550 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4551 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4552 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4553 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4555 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4556 assert_eq!(route.paths[0][1].short_channel_id, 13);
4557 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4558 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4559 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4560 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4565 fn htlc_max_reduction_below_min() {
4566 // Test that if, while walking the graph, we reduce the value being sent to meet an
4567 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4568 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4569 // resulting in us thinking there is no possible path, even if other paths exist.
4570 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4571 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4572 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4573 let payee = Payee::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4575 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4576 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4577 // then try to send 90_000.
4578 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4579 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4580 short_channel_id: 2,
4583 cltv_expiry_delta: 0,
4584 htlc_minimum_msat: 0,
4585 htlc_maximum_msat: OptionalField::Present(80_000),
4587 fee_proportional_millionths: 0,
4588 excess_data: Vec::new()
4590 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4591 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4592 short_channel_id: 4,
4595 cltv_expiry_delta: (4 << 4) | 1,
4596 htlc_minimum_msat: 90_000,
4597 htlc_maximum_msat: OptionalField::Absent,
4599 fee_proportional_millionths: 0,
4600 excess_data: Vec::new()
4604 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4605 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4606 // expensive) channels 12-13 path.
4607 let route = get_route(&our_id, &payee, &network_graph, None, 90_000, 42, Arc::clone(&logger), &scorer).unwrap();
4608 assert_eq!(route.paths.len(), 1);
4609 assert_eq!(route.paths[0].len(), 2);
4611 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4612 assert_eq!(route.paths[0][0].short_channel_id, 12);
4613 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4614 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4615 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4616 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4618 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4619 assert_eq!(route.paths[0][1].short_channel_id, 13);
4620 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4621 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4622 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
4623 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4628 fn multiple_direct_first_hops() {
4629 // Previously we'd only ever considered one first hop path per counterparty.
4630 // However, as we don't restrict users to one channel per peer, we really need to support
4631 // looking at all first hop paths.
4632 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4633 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4634 // route over multiple channels with the same first hop.
4635 let secp_ctx = Secp256k1::new();
4636 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4637 let logger = Arc::new(test_utils::TestLogger::new());
4638 let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
4639 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4640 let payee = Payee::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
4643 let route = get_route(&our_id, &payee, &network_graph, Some(&[
4644 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
4645 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
4646 ]), 100_000, 42, Arc::clone(&logger), &scorer).unwrap();
4647 assert_eq!(route.paths.len(), 1);
4648 assert_eq!(route.paths[0].len(), 1);
4650 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4651 assert_eq!(route.paths[0][0].short_channel_id, 3);
4652 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4655 let route = get_route(&our_id, &payee, &network_graph, Some(&[
4656 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4657 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4658 ]), 100_000, 42, Arc::clone(&logger), &scorer).unwrap();
4659 assert_eq!(route.paths.len(), 2);
4660 assert_eq!(route.paths[0].len(), 1);
4661 assert_eq!(route.paths[1].len(), 1);
4663 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4664 assert_eq!(route.paths[0][0].short_channel_id, 3);
4665 assert_eq!(route.paths[0][0].fee_msat, 50_000);
4667 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
4668 assert_eq!(route.paths[1][0].short_channel_id, 2);
4669 assert_eq!(route.paths[1][0].fee_msat, 50_000);
4674 fn prefers_shorter_route_with_higher_fees() {
4675 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4676 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4677 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4679 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
4680 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4681 let route = get_route(
4682 &our_id, &payee, &network_graph, None, 100, 42,
4683 Arc::clone(&logger), &scorer
4685 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4687 assert_eq!(route.get_total_fees(), 100);
4688 assert_eq!(route.get_total_amount(), 100);
4689 assert_eq!(path, vec![2, 4, 6, 11, 8]);
4691 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
4692 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
4693 let scorer = test_utils::TestScorer::with_fixed_penalty(100);
4694 let route = get_route(
4695 &our_id, &payee, &network_graph, None, 100, 42,
4696 Arc::clone(&logger), &scorer
4698 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4700 assert_eq!(route.get_total_fees(), 300);
4701 assert_eq!(route.get_total_amount(), 100);
4702 assert_eq!(path, vec![2, 4, 7, 10]);
4705 struct BadChannelScorer {
4706 short_channel_id: u64,
4710 impl Writeable for BadChannelScorer {
4711 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
4713 impl Score for BadChannelScorer {
4714 fn channel_penalty_msat(&self, short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId) -> u64 {
4715 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
4718 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4719 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
4722 struct BadNodeScorer {
4727 impl Writeable for BadNodeScorer {
4728 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
4731 impl Score for BadNodeScorer {
4732 fn channel_penalty_msat(&self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, target: &NodeId) -> u64 {
4733 if *target == self.node_id { u64::max_value() } else { 0 }
4736 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
4737 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
4741 fn avoids_routing_through_bad_channels_and_nodes() {
4742 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4743 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4744 let payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4746 // A path to nodes[6] exists when no penalties are applied to any channel.
4747 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4748 let route = get_route(
4749 &our_id, &payee, &network_graph, None, 100, 42,
4750 Arc::clone(&logger), &scorer
4752 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4754 assert_eq!(route.get_total_fees(), 100);
4755 assert_eq!(route.get_total_amount(), 100);
4756 assert_eq!(path, vec![2, 4, 6, 11, 8]);
4758 // A different path to nodes[6] exists if channel 6 cannot be routed over.
4759 let scorer = BadChannelScorer { short_channel_id: 6 };
4760 let route = get_route(
4761 &our_id, &payee, &network_graph, None, 100, 42,
4762 Arc::clone(&logger), &scorer
4764 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4766 assert_eq!(route.get_total_fees(), 300);
4767 assert_eq!(route.get_total_amount(), 100);
4768 assert_eq!(path, vec![2, 4, 7, 10]);
4770 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
4771 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
4773 &our_id, &payee, &network_graph, None, 100, 42,
4774 Arc::clone(&logger), &scorer
4776 Err(LightningError { err, .. } ) => {
4777 assert_eq!(err, "Failed to find a path to the given destination");
4779 Ok(_) => panic!("Expected error"),
4784 fn total_fees_single_path() {
4788 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
4789 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4790 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
4793 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
4794 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4795 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
4798 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
4799 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4800 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
4806 assert_eq!(route.get_total_fees(), 250);
4807 assert_eq!(route.get_total_amount(), 225);
4811 fn total_fees_multi_path() {
4815 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
4816 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4817 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
4820 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
4821 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4822 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
4826 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
4827 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4828 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
4831 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
4832 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
4833 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
4839 assert_eq!(route.get_total_fees(), 200);
4840 assert_eq!(route.get_total_amount(), 300);
4844 fn total_empty_route_no_panic() {
4845 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
4846 // would both panic if the route was completely empty. We test to ensure they return 0
4847 // here, even though its somewhat nonsensical as a route.
4848 let route = Route { paths: Vec::new(), payee: None };
4850 assert_eq!(route.get_total_fees(), 0);
4851 assert_eq!(route.get_total_amount(), 0);
4855 fn limits_total_cltv_delta() {
4856 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4857 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4859 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4861 // Make sure that generally there is at least one route available
4862 let feasible_max_total_cltv_delta = 1008;
4863 let feasible_payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
4864 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
4865 let route = get_route(&our_id, &feasible_payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer).unwrap();
4866 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4867 assert_ne!(path.len(), 0);
4869 // But not if we exclude all paths on the basis of their accumulated CLTV delta
4870 let fail_max_total_cltv_delta = 23;
4871 let fail_payee = Payee::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
4872 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
4873 match get_route(&our_id, &fail_payee, &network_graph, None, 100, 42, Arc::clone(&logger), &scorer)
4875 Err(LightningError { err, .. } ) => {
4876 assert_eq!(err, "Failed to find a path to the given destination");
4878 Ok(_) => panic!("Expected error"),
4882 #[cfg(not(feature = "no-std"))]
4883 pub(super) fn random_init_seed() -> u64 {
4884 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
4885 use core::hash::{BuildHasher, Hasher};
4886 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
4887 println!("Using seed of {}", seed);
4890 #[cfg(not(feature = "no-std"))]
4891 use util::ser::Readable;
4894 #[cfg(not(feature = "no-std"))]
4895 fn generate_routes() {
4896 let mut d = match super::test_utils::get_route_file() {
4903 let graph = NetworkGraph::read(&mut d).unwrap();
4904 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4906 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
4907 let mut seed = random_init_seed() as usize;
4908 let nodes = graph.read_only().nodes().clone();
4909 'load_endpoints: for _ in 0..10 {
4911 seed = seed.overflowing_mul(0xdeadbeef).0;
4912 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
4913 seed = seed.overflowing_mul(0xdeadbeef).0;
4914 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
4915 let payee = Payee::from_node_id(dst);
4916 let amt = seed as u64 % 200_000_000;
4917 if get_route(src, &payee, &graph, None, amt, 42, &test_utils::TestLogger::new(), &scorer).is_ok() {
4918 continue 'load_endpoints;
4925 #[cfg(not(feature = "no-std"))]
4926 fn generate_routes_mpp() {
4927 let mut d = match super::test_utils::get_route_file() {
4934 let graph = NetworkGraph::read(&mut d).unwrap();
4935 let scorer = test_utils::TestScorer::with_fixed_penalty(0);
4937 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
4938 let mut seed = random_init_seed() as usize;
4939 let nodes = graph.read_only().nodes().clone();
4940 'load_endpoints: for _ in 0..10 {
4942 seed = seed.overflowing_mul(0xdeadbeef).0;
4943 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
4944 seed = seed.overflowing_mul(0xdeadbeef).0;
4945 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
4946 let payee = Payee::from_node_id(dst).with_features(InvoiceFeatures::known());
4947 let amt = seed as u64 % 200_000_000;
4948 if get_route(src, &payee, &graph, None, amt, 42, &test_utils::TestLogger::new(), &scorer).is_ok() {
4949 continue 'load_endpoints;
4956 #[cfg(all(test, not(feature = "no-std")))]
4957 pub(crate) mod test_utils {
4959 /// Tries to open a network graph file, or panics with a URL to fetch it.
4960 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
4961 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
4962 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
4963 .or_else(|_| { // Fall back to guessing based on the binary location
4964 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
4965 let mut path = std::env::current_exe().unwrap();
4966 path.pop(); // lightning-...
4968 path.pop(); // debug
4969 path.pop(); // target
4970 path.push("lightning");
4971 path.push("net_graph-2021-05-31.bin");
4972 eprintln!("{}", path.to_str().unwrap());
4975 .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");
4976 #[cfg(require_route_graph_test)]
4977 return Ok(res.unwrap());
4978 #[cfg(not(require_route_graph_test))]
4983 #[cfg(all(test, feature = "unstable", not(feature = "no-std")))]
4986 use bitcoin::hashes::Hash;
4987 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
4988 use chain::transaction::OutPoint;
4989 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
4990 use ln::features::{InitFeatures, InvoiceFeatures};
4991 use routing::scoring::Scorer;
4992 use util::logger::{Logger, Record};
4996 struct DummyLogger {}
4997 impl Logger for DummyLogger {
4998 fn log(&self, _record: &Record) {}
5001 struct ZeroPenaltyScorer;
5002 impl Score for ZeroPenaltyScorer {
5003 fn channel_penalty_msat(
5004 &self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId
5006 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5007 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5010 fn read_network_graph() -> NetworkGraph {
5011 let mut d = test_utils::get_route_file().unwrap();
5012 NetworkGraph::read(&mut d).unwrap()
5015 fn payer_pubkey() -> PublicKey {
5016 let secp_ctx = Secp256k1::new();
5017 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5021 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5023 channel_id: [0; 32],
5024 counterparty: ChannelCounterparty {
5025 features: InitFeatures::known(),
5027 unspendable_punishment_reserve: 0,
5028 forwarding_info: None,
5030 funding_txo: Some(OutPoint {
5031 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5033 short_channel_id: Some(1),
5034 channel_value_satoshis: 10_000_000,
5036 balance_msat: 10_000_000,
5037 outbound_capacity_msat: 10_000_000,
5038 inbound_capacity_msat: 0,
5039 unspendable_punishment_reserve: None,
5040 confirmations_required: None,
5041 force_close_spend_delay: None,
5043 is_funding_locked: true,
5050 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5051 let network_graph = read_network_graph();
5052 let scorer = ZeroPenaltyScorer;
5053 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5057 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5058 let network_graph = read_network_graph();
5059 let scorer = ZeroPenaltyScorer;
5060 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5064 fn generate_routes_with_default_scorer(bench: &mut Bencher) {
5065 let network_graph = read_network_graph();
5066 let scorer = Scorer::default();
5067 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5071 fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
5072 let network_graph = read_network_graph();
5073 let scorer = Scorer::default();
5074 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5077 fn generate_routes<S: Score>(
5078 bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
5080 let nodes = graph.read_only().nodes().clone();
5081 let payer = payer_pubkey();
5083 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5084 let mut routes = Vec::new();
5085 let mut route_endpoints = Vec::new();
5086 let mut seed: usize = 0xdeadbeef;
5087 'load_endpoints: for _ in 0..100 {
5090 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5092 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5093 let payee = Payee::from_node_id(dst).with_features(features.clone());
5094 let first_hop = first_hop(src);
5095 let amt = seed as u64 % 1_000_000;
5096 if let Ok(route) = get_route(&payer, &payee, &graph, Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer) {
5098 route_endpoints.push((first_hop, payee, amt));
5099 continue 'load_endpoints;
5104 // ...and seed the scorer with success and failure data...
5105 for route in routes {
5106 let amount = route.get_total_amount();
5107 if amount < 250_000 {
5108 for path in route.paths {
5109 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5111 } else if amount > 750_000 {
5112 for path in route.paths {
5113 let short_channel_id = path[path.len() / 2].short_channel_id;
5114 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5119 // ...then benchmark finding paths between the nodes we learned.
5122 let (first_hop, payee, amt) = &route_endpoints[idx % route_endpoints.len()];
5123 assert!(get_route(&payer, payee, &graph, Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer).is_ok());