1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The top-level routing/network map tracking logic lives here.
12 //! You probably want to create a NetGraphMsgHandler and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
15 use bitcoin::secp256k1::key::PublicKey;
17 use ln::channelmanager::ChannelDetails;
18 use ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
19 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
20 use routing::scoring::Score;
21 use routing::network_graph::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
22 use util::ser::{Writeable, Readable};
23 use util::logger::{Level, Logger};
24 use util::chacha20::ChaCha20;
28 use alloc::collections::BinaryHeap;
33 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
35 /// The node_id of the node at this hop.
36 pub pubkey: PublicKey,
37 /// The node_announcement features of the node at this hop. For the last hop, these may be
38 /// amended to match the features present in the invoice this node generated.
39 pub node_features: NodeFeatures,
40 /// The channel that should be used from the previous hop to reach this node.
41 pub short_channel_id: u64,
42 /// The channel_announcement features of the channel that should be used from the previous hop
43 /// to reach this node.
44 pub channel_features: ChannelFeatures,
45 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
46 /// For the last hop, this should be the full value of the payment (might be more than
47 /// requested if we had to match htlc_minimum_msat).
49 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
50 /// expected at the destination, in excess of the current block height.
51 pub cltv_expiry_delta: u32,
54 impl_writeable_tlv_based!(RouteHop, {
55 (0, pubkey, required),
56 (2, node_features, required),
57 (4, short_channel_id, required),
58 (6, channel_features, required),
59 (8, fee_msat, required),
60 (10, cltv_expiry_delta, required),
63 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
64 /// it can take multiple paths. Each path is composed of one or more hops through the network.
65 #[derive(Clone, Hash, PartialEq, Eq)]
67 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
68 /// last RouteHop in each path must be the same.
69 /// Each entry represents a list of hops, NOT INCLUDING our own, where the last hop is the
70 /// destination. Thus, this must always be at least length one. While the maximum length of any
71 /// given path is variable, keeping the length of any path to less than 20 should currently
72 /// ensure it is viable.
73 pub paths: Vec<Vec<RouteHop>>,
74 /// The `payment_params` parameter passed to [`find_route`].
75 /// This is used by `ChannelManager` to track information which may be required for retries,
76 /// provided back to you via [`Event::PaymentPathFailed`].
78 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
79 pub payment_params: Option<PaymentParameters>,
82 pub(crate) trait RoutePath {
83 /// Gets the fees for a given path, excluding any excess paid to the recipient.
84 fn get_path_fees(&self) -> u64;
86 impl RoutePath for Vec<RouteHop> {
87 fn get_path_fees(&self) -> u64 {
88 // Do not count last hop of each path since that's the full value of the payment
89 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
90 .iter().map(|hop| &hop.fee_msat)
96 /// Returns the total amount of fees paid on this [`Route`].
98 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
99 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
100 pub fn get_total_fees(&self) -> u64 {
101 self.paths.iter().map(|path| path.get_path_fees()).sum()
104 /// Returns the total amount paid on this [`Route`], excluding the fees.
105 pub fn get_total_amount(&self) -> u64 {
106 return self.paths.iter()
107 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
112 const SERIALIZATION_VERSION: u8 = 1;
113 const MIN_SERIALIZATION_VERSION: u8 = 1;
115 impl Writeable for Route {
116 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
117 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
118 (self.paths.len() as u64).write(writer)?;
119 for hops in self.paths.iter() {
120 (hops.len() as u8).write(writer)?;
121 for hop in hops.iter() {
125 write_tlv_fields!(writer, {
126 (1, self.payment_params, option),
132 impl Readable for Route {
133 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
134 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
135 let path_count: u64 = Readable::read(reader)?;
136 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
137 for _ in 0..path_count {
138 let hop_count: u8 = Readable::read(reader)?;
139 let mut hops = Vec::with_capacity(hop_count as usize);
140 for _ in 0..hop_count {
141 hops.push(Readable::read(reader)?);
145 let mut payment_params = None;
146 read_tlv_fields!(reader, {
147 (1, payment_params, option),
149 Ok(Route { paths, payment_params })
153 /// Parameters needed to find a [`Route`].
155 /// Passed to [`find_route`] and also provided in [`Event::PaymentPathFailed`] for retrying a failed
158 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
159 #[derive(Clone, Debug)]
160 pub struct RouteParameters {
161 /// The parameters of the failed payment path.
162 pub payment_params: PaymentParameters,
164 /// The amount in msats sent on the failed payment path.
165 pub final_value_msat: u64,
167 /// The CLTV on the final hop of the failed payment path.
168 pub final_cltv_expiry_delta: u32,
171 impl_writeable_tlv_based!(RouteParameters, {
172 (0, payment_params, required),
173 (2, final_value_msat, required),
174 (4, final_cltv_expiry_delta, required),
177 /// Maximum total CTLV difference we allow for a full payment path.
178 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
180 /// The median hop CLTV expiry delta currently seen in the network.
181 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
183 /// The recipient of a payment.
184 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
185 pub struct PaymentParameters {
186 /// The node id of the payee.
187 pub payee_pubkey: PublicKey,
189 /// Features supported by the payee.
191 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
192 /// does not contain any features.
194 /// [`for_keysend`]: Self::for_keysend
195 pub features: Option<InvoiceFeatures>,
197 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
198 pub route_hints: Vec<RouteHint>,
200 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
201 pub expiry_time: Option<u64>,
203 /// The maximum total CLTV delta we accept for the route.
204 pub max_total_cltv_expiry_delta: u32,
207 impl_writeable_tlv_based!(PaymentParameters, {
208 (0, payee_pubkey, required),
209 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
210 (2, features, option),
211 (4, route_hints, vec_type),
212 (6, expiry_time, option),
215 impl PaymentParameters {
216 /// Creates a payee with the node id of the given `pubkey`.
217 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
223 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
227 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
228 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
229 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
232 /// Includes the payee's features.
234 /// (C-not exported) since bindings don't support move semantics
235 pub fn with_features(self, features: InvoiceFeatures) -> Self {
236 Self { features: Some(features), ..self }
239 /// Includes hints for routing to the payee.
241 /// (C-not exported) since bindings don't support move semantics
242 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
243 Self { route_hints, ..self }
246 /// Includes a payment expiration in seconds relative to the UNIX epoch.
248 /// (C-not exported) since bindings don't support move semantics
249 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
250 Self { expiry_time: Some(expiry_time), ..self }
253 /// Includes a limit for the total CLTV expiry delta which is considered during routing
255 /// (C-not exported) since bindings don't support move semantics
256 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
257 Self { max_total_cltv_expiry_delta, ..self }
261 /// A list of hops along a payment path terminating with a channel to the recipient.
262 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
263 pub struct RouteHint(pub Vec<RouteHintHop>);
265 impl Writeable for RouteHint {
266 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
267 (self.0.len() as u64).write(writer)?;
268 for hop in self.0.iter() {
275 impl Readable for RouteHint {
276 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
277 let hop_count: u64 = Readable::read(reader)?;
278 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
279 for _ in 0..hop_count {
280 hops.push(Readable::read(reader)?);
286 /// A channel descriptor for a hop along a payment path.
287 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
288 pub struct RouteHintHop {
289 /// The node_id of the non-target end of the route
290 pub src_node_id: PublicKey,
291 /// The short_channel_id of this channel
292 pub short_channel_id: u64,
293 /// The fees which must be paid to use this channel
294 pub fees: RoutingFees,
295 /// The difference in CLTV values between this node and the next node.
296 pub cltv_expiry_delta: u16,
297 /// The minimum value, in msat, which must be relayed to the next hop.
298 pub htlc_minimum_msat: Option<u64>,
299 /// The maximum value in msat available for routing with a single HTLC.
300 pub htlc_maximum_msat: Option<u64>,
303 impl_writeable_tlv_based!(RouteHintHop, {
304 (0, src_node_id, required),
305 (1, htlc_minimum_msat, option),
306 (2, short_channel_id, required),
307 (3, htlc_maximum_msat, option),
309 (6, cltv_expiry_delta, required),
312 #[derive(Eq, PartialEq)]
313 struct RouteGraphNode {
315 lowest_fee_to_peer_through_node: u64,
316 lowest_fee_to_node: u64,
317 total_cltv_delta: u32,
318 // The maximum value a yet-to-be-constructed payment path might flow through this node.
319 // This value is upper-bounded by us by:
320 // - how much is needed for a path being constructed
321 // - how much value can channels following this node (up to the destination) can contribute,
322 // considering their capacity and fees
323 value_contribution_msat: u64,
324 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
325 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
326 path_htlc_minimum_msat: u64,
327 /// All penalties incurred from this hop on the way to the destination, as calculated using
329 path_penalty_msat: u64,
332 impl cmp::Ord for RouteGraphNode {
333 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
334 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
335 .checked_add(other.path_penalty_msat)
336 .unwrap_or_else(|| u64::max_value());
337 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
338 .checked_add(self.path_penalty_msat)
339 .unwrap_or_else(|| u64::max_value());
340 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
344 impl cmp::PartialOrd for RouteGraphNode {
345 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
346 Some(self.cmp(other))
350 /// A wrapper around the various hop representations.
352 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
353 #[derive(Clone, Debug)]
354 enum CandidateRouteHop<'a> {
355 /// A hop from the payer, where the outbound liquidity is known.
357 details: &'a ChannelDetails,
359 /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
361 info: DirectedChannelInfoWithUpdate<'a>,
362 short_channel_id: u64,
364 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
366 hint: &'a RouteHintHop,
370 impl<'a> CandidateRouteHop<'a> {
371 fn short_channel_id(&self) -> u64 {
373 CandidateRouteHop::FirstHop { details } => details.short_channel_id.unwrap(),
374 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
375 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
379 // NOTE: This may alloc memory so avoid calling it in a hot code path.
380 fn features(&self) -> ChannelFeatures {
382 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
383 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
384 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
388 fn cltv_expiry_delta(&self) -> u32 {
390 CandidateRouteHop::FirstHop { .. } => 0,
391 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
392 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
396 fn htlc_minimum_msat(&self) -> u64 {
398 CandidateRouteHop::FirstHop { .. } => 0,
399 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
400 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
404 fn fees(&self) -> RoutingFees {
406 CandidateRouteHop::FirstHop { .. } => RoutingFees {
407 base_msat: 0, proportional_millionths: 0,
409 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
410 CandidateRouteHop::PrivateHop { hint } => hint.fees,
414 fn effective_capacity(&self) -> EffectiveCapacity {
416 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
417 liquidity_msat: details.outbound_capacity_msat,
419 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
420 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
425 /// It's useful to keep track of the hops associated with the fees required to use them,
426 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
427 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
428 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
430 struct PathBuildingHop<'a> {
431 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
432 // is a larger refactor and will require careful performance analysis.
434 candidate: CandidateRouteHop<'a>,
437 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
438 src_lowest_inbound_fees: RoutingFees,
439 /// All the fees paid *after* this channel on the way to the destination
440 next_hops_fee_msat: u64,
441 /// Fee paid for the use of the current channel (see candidate.fees()).
442 /// The value will be actually deducted from the counterparty balance on the previous link.
443 hop_use_fee_msat: u64,
444 /// Used to compare channels when choosing the for routing.
445 /// Includes paying for the use of a hop and the following hops, as well as
446 /// an estimated cost of reaching this hop.
447 /// Might get stale when fees are recomputed. Primarily for internal use.
449 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
450 /// walk and may be invalid thereafter.
451 path_htlc_minimum_msat: u64,
452 /// All penalties incurred from this channel on the way to the destination, as calculated using
454 path_penalty_msat: u64,
455 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
456 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
457 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
458 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
459 /// avoid processing them again.
461 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
462 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
463 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
464 // value_contribution_msat, which requires tracking it here. See comments below where it is
465 // used for more info.
466 value_contribution_msat: u64,
469 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
470 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
471 f.debug_struct("PathBuildingHop")
472 .field("node_id", &self.node_id)
473 .field("short_channel_id", &self.candidate.short_channel_id())
474 .field("total_fee_msat", &self.total_fee_msat)
475 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
476 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
477 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat - (&self.next_hops_fee_msat + &self.hop_use_fee_msat)))
478 .field("path_penalty_msat", &self.path_penalty_msat)
479 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
480 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta())
485 // Instantiated with a list of hops with correct data in them collected during path finding,
486 // an instance of this struct should be further modified only via given methods.
488 struct PaymentPath<'a> {
489 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
492 impl<'a> PaymentPath<'a> {
493 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
494 fn get_value_msat(&self) -> u64 {
495 self.hops.last().unwrap().0.fee_msat
498 fn get_total_fee_paid_msat(&self) -> u64 {
499 if self.hops.len() < 1 {
503 // Can't use next_hops_fee_msat because it gets outdated.
504 for (i, (hop, _)) in self.hops.iter().enumerate() {
505 if i != self.hops.len() - 1 {
506 result += hop.fee_msat;
512 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
513 // to change fees may result in an inconsistency.
515 // Sometimes we call this function right after constructing a path which is inconsistent in
516 // that it the value being transferred has decreased while we were doing path finding, leading
517 // to the fees being paid not lining up with the actual limits.
519 // Note that this function is not aware of the available_liquidity limit, and thus does not
520 // support increasing the value being transferred.
521 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
522 assert!(value_msat <= self.hops.last().unwrap().0.fee_msat);
524 let mut total_fee_paid_msat = 0 as u64;
525 for i in (0..self.hops.len()).rev() {
526 let last_hop = i == self.hops.len() - 1;
528 // For non-last-hop, this value will represent the fees paid on the current hop. It
529 // will consist of the fees for the use of the next hop, and extra fees to match
530 // htlc_minimum_msat of the current channel. Last hop is handled separately.
531 let mut cur_hop_fees_msat = 0;
533 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
536 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
537 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
538 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
539 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
540 // set it too high just to maliciously take more fees by exploiting this
541 // match htlc_minimum_msat logic.
542 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
543 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
544 // Note that there is a risk that *previous hops* (those closer to us, as we go
545 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
547 // This might make us end up with a broken route, although this should be super-rare
548 // in practice, both because of how healthy channels look like, and how we pick
549 // channels in add_entry.
550 // Also, this can't be exploited more heavily than *announce a free path and fail
552 cur_hop_transferred_amount_msat += extra_fees_msat;
553 total_fee_paid_msat += extra_fees_msat;
554 cur_hop_fees_msat += extra_fees_msat;
558 // Final hop is a special case: it usually has just value_msat (by design), but also
559 // it still could overpay for the htlc_minimum_msat.
560 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
562 // Propagate updated fees for the use of the channels to one hop back, where they
563 // will be actually paid (fee_msat). The last hop is handled above separately.
564 cur_hop.fee_msat = cur_hop_fees_msat;
567 // Fee for the use of the current hop which will be deducted on the previous hop.
568 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
569 // this channel is free for us.
571 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
572 cur_hop.hop_use_fee_msat = new_fee;
573 total_fee_paid_msat += new_fee;
575 // It should not be possible because this function is called only to reduce the
576 // value. In that case, compute_fee was already called with the same fees for
577 // larger amount and there was no overflow.
585 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
586 let proportional_fee_millions =
587 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
588 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
589 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
593 // This function may be (indirectly) called without any verification,
594 // with channel_fees provided by a caller. We should handle it gracefully.
599 /// Finds a route from us (payer) to the given target node (payee).
601 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
602 /// Without this, MPP will only be used if the payee's features are available in the network graph.
604 /// Private routing paths between a public node and the target may be included in `params.payee`.
606 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
607 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
608 /// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
610 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
611 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
612 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
616 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
617 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
622 /// Panics if first_hops contains channels without short_channel_ids;
623 /// [`ChannelManager::list_usable_channels`] will never include such channels.
625 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
626 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
627 pub fn find_route<L: Deref, S: Score>(
628 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network: &NetworkGraph,
629 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
630 ) -> Result<Route, LightningError>
631 where L::Target: Logger {
632 let network_graph = network.read_only();
634 our_node_pubkey, &route_params.payment_params, &network_graph, first_hops, route_params.final_value_msat,
635 route_params.final_cltv_expiry_delta, logger, scorer, random_seed_bytes
638 add_random_cltv_offset(&mut route, &route_params.payment_params, &network_graph, random_seed_bytes);
641 Err(err) => Err(err),
645 pub(crate) fn get_route<L: Deref, S: Score>(
646 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
647 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
648 logger: L, scorer: &S, _random_seed_bytes: &[u8; 32]
649 ) -> Result<Route, LightningError>
650 where L::Target: Logger {
651 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
652 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
654 if payee_node_id == our_node_id {
655 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
658 if final_value_msat > MAX_VALUE_MSAT {
659 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
662 if final_value_msat == 0 {
663 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
666 for route in payment_params.route_hints.iter() {
667 for hop in &route.0 {
668 if hop.src_node_id == payment_params.payee_pubkey {
669 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
673 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
674 return Err(LightningError{err: "Can't find a route where the maximum total CLTV expiry delta is below the final CLTV expiry.".to_owned(), action: ErrorAction::IgnoreError});
677 // The general routing idea is the following:
678 // 1. Fill first/last hops communicated by the caller.
679 // 2. Attempt to construct a path from payer to payee for transferring
680 // any ~sufficient (described later) value.
681 // If succeed, remember which channels were used and how much liquidity they have available,
682 // so that future paths don't rely on the same liquidity.
683 // 3. Proceed to the next step if:
684 // - we hit the recommended target value;
685 // - OR if we could not construct a new path. Any next attempt will fail too.
686 // Otherwise, repeat step 2.
687 // 4. See if we managed to collect paths which aggregately are able to transfer target value
688 // (not recommended value).
689 // 5. If yes, proceed. If not, fail routing.
690 // 6. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
691 // 7. Of all the found paths, select only those with the lowest total fee.
692 // 8. The last path in every selected route is likely to be more than we need.
693 // Reduce its value-to-transfer and recompute fees.
694 // 9. Choose the best route by the lowest total fee.
696 // As for the actual search algorithm,
697 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
698 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
700 // We are not a faithful Dijkstra's implementation because we can change values which impact
701 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
702 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
703 // the value we are currently attempting to send over a path, we simply reduce the value being
704 // sent along the path for any hops after that channel. This may imply that later fees (which
705 // we've already tabulated) are lower because a smaller value is passing through the channels
706 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
707 // channels which were selected earlier (and which may still be used for other paths without a
708 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
711 // One potentially problematic case for this algorithm would be if there are many
712 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
713 // graph walking), we may never find a path which is not liquidity-limited and has lower
714 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
715 // Because we only consider paths with at least 5% of the total value being sent, the damage
716 // from such a case should be limited, however this could be further reduced in the future by
717 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
718 // limits for the purposes of fee calculation.
720 // Alternatively, we could store more detailed path information in the heap (targets, below)
721 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
722 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
723 // and practically (as we would need to store dynamically-allocated path information in heap
724 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
725 // results of such an algorithm would likely be biased towards lower-value paths.
727 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
728 // outside of our current search value, running a path search more times to gather candidate
729 // paths at different values. While this may be acceptable, further path searches may increase
730 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
731 // graph for candidate paths, calculating the maximum value which can realistically be sent at
732 // the same time, remaining generic across different payment values.
734 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
735 // to use as the A* heuristic beyond just the cost to get one node further than the current
738 let network_channels = network_graph.channels();
739 let network_nodes = network_graph.nodes();
741 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
742 // it. If the payee supports it they're supposed to include it in the invoice, so that should
744 let allow_mpp = if let Some(features) = &payment_params.features {
745 features.supports_basic_mpp()
746 } else if let Some(node) = network_nodes.get(&payee_node_id) {
747 if let Some(node_info) = node.announcement_info.as_ref() {
748 node_info.features.supports_basic_mpp()
751 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
752 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
753 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
756 // Prepare the data we'll use for payee-to-payer search by
757 // inserting first hops suggested by the caller as targets.
758 // Our search will then attempt to reach them while traversing from the payee node.
759 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
760 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
761 if let Some(hops) = first_hops {
763 if chan.short_channel_id.is_none() {
764 panic!("first_hops should be filled in with usable channels, not pending ones");
766 if chan.counterparty.node_id == *our_node_pubkey {
767 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
770 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
771 .or_insert(Vec::new())
774 if first_hop_targets.is_empty() {
775 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
779 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
780 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
781 // adding duplicate entries when we find a better path to a given node.
782 let mut targets = BinaryHeap::new();
784 // Map from node_id to information about the best current path to that node, including feerate
786 let mut dist = HashMap::with_capacity(network_nodes.len());
788 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
789 // indicating that we may wish to try again with a higher value, potentially paying to meet an
790 // htlc_minimum with extra fees while still finding a cheaper path.
791 let mut hit_minimum_limit;
793 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
794 // We start with a path_value of the exact amount we want, and if that generates a route we may
795 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
796 // amount we want in total across paths, selecting the best subset at the end.
797 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
798 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
799 let mut path_value_msat = final_value_msat;
801 // We don't want multiple paths (as per MPP) share liquidity of the same channels.
802 // This map allows paths to be aware of the channel use by other paths in the same call.
803 // This would help to make a better path finding decisions and not "overbook" channels.
804 // It is unaware of the directions (except for `outbound_capacity_msat` in `first_hops`).
805 let mut bookkept_channels_liquidity_available_msat = HashMap::with_capacity(network_nodes.len());
807 // Keeping track of how much value we already collected across other paths. Helps to decide:
808 // - how much a new path should be transferring (upper bound);
809 // - whether a channel should be disregarded because
810 // it's available liquidity is too small comparing to how much more we need to collect;
811 // - when we want to stop looking for new paths.
812 let mut already_collected_value_msat = 0;
814 for (_, channels) in first_hop_targets.iter_mut() {
815 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
818 // First, if channels are below `recommended_value_msat`, sort them in descending order,
819 // preferring larger channels to avoid splitting the payment into more MPP parts than is
822 // Second, because simply always sorting in descending order would always use our largest
823 // available outbound capacity, needlessly fragmenting our available channel capacities,
824 // sort channels above `recommended_value_msat` in ascending order, preferring channels
825 // which have enough, but not too much, capacity for the payment.
826 channels.sort_unstable_by(|chan_a, chan_b| {
827 if chan_b.outbound_capacity_msat < recommended_value_msat || chan_a.outbound_capacity_msat < recommended_value_msat {
828 // Sort in descending order
829 chan_b.outbound_capacity_msat.cmp(&chan_a.outbound_capacity_msat)
831 // Sort in ascending order
832 chan_a.outbound_capacity_msat.cmp(&chan_b.outbound_capacity_msat)
837 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
839 macro_rules! add_entry {
840 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
841 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
842 // since that value has to be transferred over this channel.
843 // Returns whether this channel caused an update to `targets`.
844 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
845 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
846 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => { {
847 // We "return" whether we updated the path at the end, via this:
848 let mut did_add_update_path_to_src_node = false;
849 // Channels to self should not be used. This is more of belt-and-suspenders, because in
850 // practice these cases should be caught earlier:
851 // - for regular channels at channel announcement (TODO)
852 // - for first and last hops early in get_route
853 if $src_node_id != $dest_node_id {
854 let short_channel_id = $candidate.short_channel_id();
855 let available_liquidity_msat = bookkept_channels_liquidity_available_msat
856 .entry(short_channel_id)
857 .or_insert_with(|| $candidate.effective_capacity().as_msat());
859 // It is tricky to substract $next_hops_fee_msat from available liquidity here.
860 // It may be misleading because we might later choose to reduce the value transferred
861 // over these channels, and the channel which was insufficient might become sufficient.
862 // Worst case: we drop a good channel here because it can't cover the high following
863 // fees caused by one expensive channel, but then this channel could have been used
864 // if the amount being transferred over this path is lower.
865 // We do this for now, but this is a subject for removal.
866 if let Some(available_value_contribution_msat) = available_liquidity_msat.checked_sub($next_hops_fee_msat) {
868 // Routing Fragmentation Mitigation heuristic:
870 // Routing fragmentation across many payment paths increases the overall routing
871 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
872 // Taking too many smaller paths also increases the chance of payment failure.
873 // Thus to avoid this effect, we require from our collected links to provide
874 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
876 // This requirement is currently 5% of the remaining-to-be-collected value.
877 // This means as we successfully advance in our collection,
878 // the absolute liquidity contribution is lowered,
879 // thus increasing the number of potential channels to be selected.
881 // Derive the minimal liquidity contribution with a ratio of 20 (5%, rounded up)
882 // or 100% if we're not allowed to do multipath payments.
883 let minimal_value_contribution_msat: u64 = if allow_mpp {
884 (recommended_value_msat - already_collected_value_msat + 19) / 20
888 // Verify the liquidity offered by this channel complies to the minimal contribution.
889 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
891 // Do not consider candidates that exceed the maximum total cltv expiry limit.
892 // In order to already account for some of the privacy enhancing random CLTV
893 // expiry delta offset we add on top later, we subtract a rough estimate
894 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
895 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
896 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
897 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
898 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
899 .checked_add($candidate.cltv_expiry_delta())
900 .unwrap_or(u32::max_value());
901 let doesnt_exceed_cltv_delta_limit = hop_total_cltv_delta <= max_total_cltv_expiry_delta;
903 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
904 // Includes paying fees for the use of the following channels.
905 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
906 Some(result) => result,
907 // Can't overflow due to how the values were computed right above.
908 None => unreachable!(),
910 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
911 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
912 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
914 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
915 // bother considering this channel.
916 // Since we're choosing amount_to_transfer_over_msat as maximum possible, it can
917 // be only reduced later (not increased), so this channel should just be skipped
918 // as not sufficient.
919 if !over_path_minimum_msat && doesnt_exceed_cltv_delta_limit {
920 hit_minimum_limit = true;
921 } else if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit {
922 // Note that low contribution here (limited by available_liquidity_msat)
923 // might violate htlc_minimum_msat on the hops which are next along the
924 // payment path (upstream to the payee). To avoid that, we recompute
925 // path fees knowing the final path contribution after constructing it.
926 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
927 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
928 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
929 .unwrap_or_else(|| u64::max_value());
930 let hm_entry = dist.entry($src_node_id);
931 let old_entry = hm_entry.or_insert_with(|| {
932 // If there was previously no known way to access the source node
933 // (recall it goes payee-to-payer) of short_channel_id, first add a
934 // semi-dummy record just to compute the fees to reach the source node.
935 // This will affect our decision on selecting short_channel_id
936 // as a way to reach the $dest_node_id.
937 let mut fee_base_msat = 0;
938 let mut fee_proportional_millionths = 0;
939 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
940 fee_base_msat = fees.base_msat;
941 fee_proportional_millionths = fees.proportional_millionths;
944 node_id: $dest_node_id.clone(),
945 candidate: $candidate.clone(),
947 src_lowest_inbound_fees: RoutingFees {
948 base_msat: fee_base_msat,
949 proportional_millionths: fee_proportional_millionths,
951 next_hops_fee_msat: u64::max_value(),
952 hop_use_fee_msat: u64::max_value(),
953 total_fee_msat: u64::max_value(),
954 path_htlc_minimum_msat,
955 path_penalty_msat: u64::max_value(),
956 was_processed: false,
957 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
958 value_contribution_msat,
962 #[allow(unused_mut)] // We only use the mut in cfg(test)
963 let mut should_process = !old_entry.was_processed;
964 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
966 // In test/fuzzing builds, we do extra checks to make sure the skipping
967 // of already-seen nodes only happens in cases we expect (see below).
968 if !should_process { should_process = true; }
972 let mut hop_use_fee_msat = 0;
973 let mut total_fee_msat = $next_hops_fee_msat;
975 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
976 // will have the same effective-fee
977 if $src_node_id != our_node_id {
978 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
979 // max_value means we'll always fail
980 // the old_entry.total_fee_msat > total_fee_msat check
981 None => total_fee_msat = u64::max_value(),
983 hop_use_fee_msat = fee_msat;
984 total_fee_msat += hop_use_fee_msat;
985 // When calculating the lowest inbound fees to a node, we
986 // calculate fees here not based on the actual value we think
987 // will flow over this channel, but on the minimum value that
988 // we'll accept flowing over it. The minimum accepted value
989 // is a constant through each path collection run, ensuring
990 // consistent basis. Otherwise we may later find a
991 // different path to the source node that is more expensive,
992 // but which we consider to be cheaper because we are capacity
993 // constrained and the relative fee becomes lower.
994 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
995 .map(|a| a.checked_add(total_fee_msat)) {
1000 total_fee_msat = u64::max_value();
1007 let path_penalty_msat = $next_hops_path_penalty_msat.checked_add(
1008 scorer.channel_penalty_msat(short_channel_id, amount_to_transfer_over_msat, *available_liquidity_msat,
1009 &$src_node_id, &$dest_node_id)).unwrap_or_else(|| u64::max_value());
1010 let new_graph_node = RouteGraphNode {
1011 node_id: $src_node_id,
1012 lowest_fee_to_peer_through_node: total_fee_msat,
1013 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1014 total_cltv_delta: hop_total_cltv_delta,
1015 value_contribution_msat: value_contribution_msat,
1016 path_htlc_minimum_msat,
1020 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1021 // if this way is cheaper than the already known
1022 // (considering the cost to "reach" this channel from the route destination,
1023 // the cost of using this channel,
1024 // and the cost of routing to the source node of this channel).
1025 // Also, consider that htlc_minimum_msat_difference, because we might end up
1026 // paying it. Consider the following exploit:
1027 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1028 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1029 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1030 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1032 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1033 // but it may require additional tracking - we don't want to double-count
1034 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1035 // can't use something that may decrease on future hops.
1036 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1037 .checked_add(old_entry.path_penalty_msat)
1038 .unwrap_or_else(|| u64::max_value());
1039 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1040 .checked_add(path_penalty_msat)
1041 .unwrap_or_else(|| u64::max_value());
1043 if !old_entry.was_processed && new_cost < old_cost {
1044 targets.push(new_graph_node);
1045 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1046 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1047 old_entry.total_fee_msat = total_fee_msat;
1048 old_entry.node_id = $dest_node_id.clone();
1049 old_entry.candidate = $candidate.clone();
1050 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1051 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1052 old_entry.path_penalty_msat = path_penalty_msat;
1053 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1055 old_entry.value_contribution_msat = value_contribution_msat;
1057 did_add_update_path_to_src_node = true;
1058 } else if old_entry.was_processed && new_cost < old_cost {
1059 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1061 // If we're skipping processing a node which was previously
1062 // processed even though we found another path to it with a
1063 // cheaper fee, check that it was because the second path we
1064 // found (which we are processing now) has a lower value
1065 // contribution due to an HTLC minimum limit.
1067 // e.g. take a graph with two paths from node 1 to node 2, one
1068 // through channel A, and one through channel B. Channel A and
1069 // B are both in the to-process heap, with their scores set by
1070 // a higher htlc_minimum than fee.
1071 // Channel A is processed first, and the channels onwards from
1072 // node 1 are added to the to-process heap. Thereafter, we pop
1073 // Channel B off of the heap, note that it has a much more
1074 // restrictive htlc_maximum_msat, and recalculate the fees for
1075 // all of node 1's channels using the new, reduced, amount.
1077 // This would be bogus - we'd be selecting a higher-fee path
1078 // with a lower htlc_maximum_msat instead of the one we'd
1079 // already decided to use.
1080 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1082 value_contribution_msat + path_penalty_msat <
1083 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1091 did_add_update_path_to_src_node
1095 let empty_node_features = NodeFeatures::empty();
1096 // Find ways (channels with destination) to reach a given node and store them
1097 // in the corresponding data structures (routing graph etc).
1098 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1099 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1100 // This data can later be helpful to optimize routing (pay lower fees).
1101 macro_rules! add_entries_to_cheapest_to_target_node {
1102 ( $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, $next_hops_cltv_delta: expr ) => {
1103 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1104 let was_processed = elem.was_processed;
1105 elem.was_processed = true;
1108 // Entries are added to dist in add_entry!() when there is a channel from a node.
1109 // Because there are no channels from payee, it will not have a dist entry at this point.
1110 // If we're processing any other node, it is always be the result of a channel from it.
1111 assert_eq!($node_id, payee_node_id);
1116 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1117 for details in first_channels {
1118 let candidate = CandidateRouteHop::FirstHop { details };
1119 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);
1123 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1126 &empty_node_features
1129 if !features.requires_unknown_bits() {
1130 for chan_id in $node.channels.iter() {
1131 let chan = network_channels.get(chan_id).unwrap();
1132 if !chan.features.requires_unknown_bits() {
1133 let (directed_channel, source) =
1134 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1135 if first_hops.is_none() || *source != our_node_id {
1136 if let Some(direction) = directed_channel.direction() {
1137 if direction.enabled {
1138 let candidate = CandidateRouteHop::PublicHop {
1139 info: directed_channel.with_update().unwrap(),
1140 short_channel_id: *chan_id,
1142 add_entry!(candidate, *source, $node_id, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1153 let mut payment_paths = Vec::<PaymentPath>::new();
1155 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1156 'paths_collection: loop {
1157 // For every new path, start from scratch, except
1158 // bookkept_channels_liquidity_available_msat, which will improve
1159 // the further iterations of path finding. Also don't erase first_hop_targets.
1162 hit_minimum_limit = false;
1164 // If first hop is a private channel and the only way to reach the payee, this is the only
1165 // place where it could be added.
1166 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1167 for details in first_channels {
1168 let candidate = CandidateRouteHop::FirstHop { details };
1169 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1170 log_trace!(logger, "{} direct route to payee via SCID {}", if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1174 // Add the payee as a target, so that the payee-to-payer
1175 // search algorithm knows what to start with.
1176 match network_nodes.get(&payee_node_id) {
1177 // The payee is not in our network graph, so nothing to add here.
1178 // There is still a chance of reaching them via last_hops though,
1179 // so don't yet fail the payment here.
1180 // If not, targets.pop() will not even let us enter the loop in step 2.
1183 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1188 // If a caller provided us with last hops, add them to routing targets. Since this happens
1189 // earlier than general path finding, they will be somewhat prioritized, although currently
1190 // it matters only if the fees are exactly the same.
1191 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1192 let first_hop_in_route = &(route.0)[0];
1193 let have_hop_src_in_graph =
1194 // Only add the hops in this route to our candidate set if either
1195 // we have a direct channel to the first hop or the first hop is
1196 // in the regular network graph.
1197 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1198 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1199 if have_hop_src_in_graph {
1200 // We start building the path from reverse, i.e., from payee
1201 // to the first RouteHintHop in the path.
1202 let hop_iter = route.0.iter().rev();
1203 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1204 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1205 let mut hop_used = true;
1206 let mut aggregate_next_hops_fee_msat: u64 = 0;
1207 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1208 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1209 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1211 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1212 let source = NodeId::from_pubkey(&hop.src_node_id);
1213 let target = NodeId::from_pubkey(&prev_hop_id);
1214 let candidate = network_channels
1215 .get(&hop.short_channel_id)
1216 .and_then(|channel| channel.as_directed_to(&target))
1217 .and_then(|(channel, _)| channel.with_update())
1218 .map(|info| CandidateRouteHop::PublicHop {
1220 short_channel_id: hop.short_channel_id,
1222 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1223 let capacity_msat = candidate.effective_capacity().as_msat();
1224 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1225 .checked_add(scorer.channel_penalty_msat(hop.short_channel_id, final_value_msat, capacity_msat, &source, &target))
1226 .unwrap_or_else(|| u64::max_value());
1228 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1229 .checked_add(hop.cltv_expiry_delta as u32)
1230 .unwrap_or_else(|| u32::max_value());
1232 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) {
1233 // If this hop was not used then there is no use checking the preceding hops
1234 // in the RouteHint. We can break by just searching for a direct channel between
1235 // last checked hop and first_hop_targets
1239 // Searching for a direct channel between last checked hop and first_hop_targets
1240 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1241 for details in first_channels {
1242 let candidate = CandidateRouteHop::FirstHop { details };
1243 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);
1251 // In the next values of the iterator, the aggregate fees already reflects
1252 // the sum of value sent from payer (final_value_msat) and routing fees
1253 // for the last node in the RouteHint. We need to just add the fees to
1254 // route through the current node so that the preceeding node (next iteration)
1256 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1257 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1258 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1260 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1261 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1262 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1263 .checked_add(hop_htlc_minimum_msat_inc);
1264 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1266 if idx == route.0.len() - 1 {
1267 // The last hop in this iterator is the first hop in
1268 // overall RouteHint.
1269 // If this hop connects to a node with which we have a direct channel,
1270 // ignore the network graph and, if the last hop was added, add our
1271 // direct channel to the candidate set.
1273 // Note that we *must* check if the last hop was added as `add_entry`
1274 // always assumes that the third argument is a node to which we have a
1276 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1277 for details in first_channels {
1278 let candidate = CandidateRouteHop::FirstHop { details };
1279 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);
1287 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1289 // At this point, targets are filled with the data from first and
1290 // last hops communicated by the caller, and the payment receiver.
1291 let mut found_new_path = false;
1294 // If this loop terminates due the exhaustion of targets, two situations are possible:
1295 // - not enough outgoing liquidity:
1296 // 0 < already_collected_value_msat < final_value_msat
1297 // - enough outgoing liquidity:
1298 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1299 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1300 // paths_collection will be stopped because found_new_path==false.
1301 // This is not necessarily a routing failure.
1302 '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() {
1304 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1305 // traversing the graph and arrange the path out of what we found.
1306 if node_id == our_node_id {
1307 let mut new_entry = dist.remove(&our_node_id).unwrap();
1308 let mut ordered_hops = vec!((new_entry.clone(), NodeFeatures::empty()));
1311 let mut features_set = false;
1312 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1313 for details in first_channels {
1314 if details.short_channel_id.unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1315 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1316 features_set = true;
1322 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1323 if let Some(node_info) = node.announcement_info.as_ref() {
1324 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1326 ordered_hops.last_mut().unwrap().1 = NodeFeatures::empty();
1329 // We can fill in features for everything except hops which were
1330 // provided via the invoice we're paying. We could guess based on the
1331 // recipient's features but for now we simply avoid guessing at all.
1335 // Means we succesfully traversed from the payer to the payee, now
1336 // save this path for the payment route. Also, update the liquidity
1337 // remaining on the used hops, so that we take them into account
1338 // while looking for more paths.
1339 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1343 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1344 Some(payment_hop) => payment_hop,
1345 // We can't arrive at None because, if we ever add an entry to targets,
1346 // we also fill in the entry in dist (see add_entry!).
1347 None => unreachable!(),
1349 // We "propagate" the fees one hop backward (topologically) here,
1350 // so that fees paid for a HTLC forwarding on the current channel are
1351 // associated with the previous channel (where they will be subtracted).
1352 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1353 ordered_hops.push((new_entry.clone(), NodeFeatures::empty()));
1355 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1356 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1358 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1359 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1361 let mut payment_path = PaymentPath {hops: ordered_hops};
1363 // We could have possibly constructed a slightly inconsistent path: since we reduce
1364 // value being transferred along the way, we could have violated htlc_minimum_msat
1365 // on some channels we already passed (assuming dest->source direction). Here, we
1366 // recompute the fees again, so that if that's the case, we match the currently
1367 // underpaid htlc_minimum_msat with fees.
1368 payment_path.update_value_and_recompute_fees(cmp::min(value_contribution_msat, final_value_msat));
1370 // Since a path allows to transfer as much value as
1371 // the smallest channel it has ("bottleneck"), we should recompute
1372 // the fees so sender HTLC don't overpay fees when traversing
1373 // larger channels than the bottleneck. This may happen because
1374 // when we were selecting those channels we were not aware how much value
1375 // this path will transfer, and the relative fee for them
1376 // might have been computed considering a larger value.
1377 // Remember that we used these channels so that we don't rely
1378 // on the same liquidity in future paths.
1379 let mut prevented_redundant_path_selection = false;
1380 for (payment_hop, _) in payment_path.hops.iter() {
1381 let channel_liquidity_available_msat = bookkept_channels_liquidity_available_msat.get_mut(&payment_hop.candidate.short_channel_id()).unwrap();
1382 let mut spent_on_hop_msat = value_contribution_msat;
1383 let next_hops_fee_msat = payment_hop.next_hops_fee_msat;
1384 spent_on_hop_msat += next_hops_fee_msat;
1385 if spent_on_hop_msat == *channel_liquidity_available_msat {
1386 // If this path used all of this channel's available liquidity, we know
1387 // this path will not be selected again in the next loop iteration.
1388 prevented_redundant_path_selection = true;
1390 *channel_liquidity_available_msat -= spent_on_hop_msat;
1392 if !prevented_redundant_path_selection {
1393 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1394 // we'll probably end up picking the same path again on the next iteration.
1395 // Decrease the available liquidity of a hop in the middle of the path.
1396 let victim_scid = payment_path.hops[(payment_path.hops.len() - 1) / 2].0.candidate.short_channel_id();
1397 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1398 let victim_liquidity = bookkept_channels_liquidity_available_msat.get_mut(&victim_scid).unwrap();
1399 *victim_liquidity = 0;
1402 // Track the total amount all our collected paths allow to send so that we:
1403 // - know when to stop looking for more paths
1404 // - know which of the hops are useless considering how much more sats we need
1405 // (contributes_sufficient_value)
1406 already_collected_value_msat += value_contribution_msat;
1408 payment_paths.push(payment_path);
1409 found_new_path = true;
1410 break 'path_construction;
1413 // If we found a path back to the payee, we shouldn't try to process it again. This is
1414 // the equivalent of the `elem.was_processed` check in
1415 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1416 if node_id == payee_node_id { continue 'path_construction; }
1418 // Otherwise, since the current target node is not us,
1419 // keep "unrolling" the payment graph from payee to payer by
1420 // finding a way to reach the current target from the payer side.
1421 match network_nodes.get(&node_id) {
1424 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);
1430 // If we don't support MPP, no use trying to gather more value ever.
1431 break 'paths_collection;
1435 // Stop either when the recommended value is reached or if no new path was found in this
1437 // In the latter case, making another path finding attempt won't help,
1438 // because we deterministically terminated the search due to low liquidity.
1439 if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1440 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1441 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1442 break 'paths_collection;
1443 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1444 // Further, if this was our first walk of the graph, and we weren't limited by an
1445 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1446 // limited by an htlc_minimum_msat value, find another path with a higher value,
1447 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1448 // still keeping a lower total fee than this path.
1449 if !hit_minimum_limit {
1450 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1451 break 'paths_collection;
1453 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1454 path_value_msat = recommended_value_msat;
1459 if payment_paths.len() == 0 {
1460 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1463 if already_collected_value_msat < final_value_msat {
1464 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1467 // Sort by total fees and take the best paths.
1468 payment_paths.sort_by_key(|path| path.get_total_fee_paid_msat());
1469 if payment_paths.len() > 50 {
1470 payment_paths.truncate(50);
1473 // Draw multiple sufficient routes by randomly combining the selected paths.
1474 let mut drawn_routes = Vec::new();
1475 for i in 0..payment_paths.len() {
1476 let mut cur_route = Vec::<PaymentPath>::new();
1477 let mut aggregate_route_value_msat = 0;
1480 // TODO: real random shuffle
1481 // Currently just starts with i_th and goes up to i-1_th in a looped way.
1482 let cur_payment_paths = [&payment_paths[i..], &payment_paths[..i]].concat();
1485 for payment_path in cur_payment_paths {
1486 cur_route.push(payment_path.clone());
1487 aggregate_route_value_msat += payment_path.get_value_msat();
1488 if aggregate_route_value_msat > final_value_msat {
1489 // Last path likely overpaid. Substract it from the most expensive
1490 // (in terms of proportional fee) path in this route and recompute fees.
1491 // This might be not the most economically efficient way, but fewer paths
1492 // also makes routing more reliable.
1493 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1495 // First, drop some expensive low-value paths entirely if possible.
1496 // Sort by value so that we drop many really-low values first, since
1497 // fewer paths is better: the payment is less likely to fail.
1498 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1499 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1500 cur_route.sort_by_key(|path| path.get_value_msat());
1501 // We should make sure that at least 1 path left.
1502 let mut paths_left = cur_route.len();
1503 cur_route.retain(|path| {
1504 if paths_left == 1 {
1507 let mut keep = true;
1508 let path_value_msat = path.get_value_msat();
1509 if path_value_msat <= overpaid_value_msat {
1511 overpaid_value_msat -= path_value_msat;
1517 if overpaid_value_msat == 0 {
1521 assert!(cur_route.len() > 0);
1524 // Now, substract the overpaid value from the most-expensive path.
1525 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1526 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1527 cur_route.sort_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1528 let expensive_payment_path = cur_route.first_mut().unwrap();
1529 // We already dropped all the small channels above, meaning all the
1530 // remaining channels are larger than remaining overpaid_value_msat.
1531 // Thus, this can't be negative.
1532 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1533 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1537 drawn_routes.push(cur_route);
1541 // Select the best route by lowest total fee.
1542 drawn_routes.sort_by_key(|paths| paths.iter().map(|path| path.get_total_fee_paid_msat()).sum::<u64>());
1543 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1544 for payment_path in drawn_routes.first().unwrap() {
1545 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1547 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)})?,
1548 node_features: node_features.clone(),
1549 short_channel_id: payment_hop.candidate.short_channel_id(),
1550 channel_features: payment_hop.candidate.features(),
1551 fee_msat: payment_hop.fee_msat,
1552 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1554 }).collect::<Vec<_>>();
1555 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1556 // applicable for the previous hop.
1557 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1558 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1560 selected_paths.push(path);
1563 if let Some(features) = &payment_params.features {
1564 for path in selected_paths.iter_mut() {
1565 if let Ok(route_hop) = path.last_mut().unwrap() {
1566 route_hop.node_features = features.to_context();
1572 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1573 payment_params: Some(payment_params.clone()),
1575 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1579 // When an adversarial intermediary node observes a payment, it may be able to infer its
1580 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1581 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1582 // payment path by adding a randomized 'shadow route' offset to the final hop.
1583 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]) {
1584 let network_channels = network_graph.channels();
1585 let network_nodes = network_graph.nodes();
1587 for path in route.paths.iter_mut() {
1588 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1590 // Remember the last three nodes of the random walk and avoid looping back on them.
1591 // Init with the last three nodes from the actual path, if possible.
1592 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1593 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1594 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1596 // Choose the last publicly known node as the starting point for the random walk.
1597 let mut cur_hop: Option<NodeId> = None;
1598 let mut path_nonce = [0u8; 12];
1599 if let Some(starting_hop) = path.iter().rev()
1600 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1601 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1602 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1605 // Init PRNG with the path-dependant nonce, which is static for private paths.
1606 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1607 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1609 // Pick a random path length in [1 .. 3]
1610 prng.process_in_place(&mut random_path_bytes);
1611 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1613 for random_hop in 0..random_walk_length {
1614 // If we don't find a suitable offset in the public network graph, we default to
1615 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1616 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1618 if let Some(cur_node_id) = cur_hop {
1619 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1620 // Randomly choose the next unvisited hop.
1621 prng.process_in_place(&mut random_path_bytes);
1622 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1623 .checked_rem(cur_node.channels.len())
1624 .and_then(|index| cur_node.channels.get(index))
1625 .and_then(|id| network_channels.get(id)) {
1626 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1627 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1628 nodes_to_avoid[random_hop] = *next_id;
1629 dir_info.direction().map(|channel_update_info| {
1630 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1631 cur_hop = Some(*next_id);
1639 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1640 .checked_add(random_hop_offset)
1641 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1644 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1645 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1646 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1648 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1649 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1650 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1651 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1652 max_path_offset = cmp::max(
1653 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1654 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1655 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1657 // Add 'shadow' CLTV offset to the final hop
1658 if let Some(last_hop) = path.last_mut() {
1659 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1660 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1667 use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
1668 use routing::router::{get_route, add_random_cltv_offset, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA};
1669 use routing::scoring::Score;
1670 use chain::transaction::OutPoint;
1671 use chain::keysinterface::KeysInterface;
1672 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1673 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1674 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1675 use ln::channelmanager;
1676 use util::test_utils;
1677 use util::chacha20::ChaCha20;
1678 use util::ser::Writeable;
1680 use util::ser::Writer;
1682 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1683 use bitcoin::hashes::Hash;
1684 use bitcoin::network::constants::Network;
1685 use bitcoin::blockdata::constants::genesis_block;
1686 use bitcoin::blockdata::script::Builder;
1687 use bitcoin::blockdata::opcodes;
1688 use bitcoin::blockdata::transaction::TxOut;
1692 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
1693 use bitcoin::secp256k1::{Secp256k1, All};
1696 use sync::{self, Arc};
1698 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1699 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1700 channelmanager::ChannelDetails {
1701 channel_id: [0; 32],
1702 counterparty: channelmanager::ChannelCounterparty {
1705 unspendable_punishment_reserve: 0,
1706 forwarding_info: None,
1708 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1710 inbound_scid_alias: None,
1711 channel_value_satoshis: 0,
1714 outbound_capacity_msat,
1715 inbound_capacity_msat: 42,
1716 unspendable_punishment_reserve: None,
1717 confirmations_required: None,
1718 force_close_spend_delay: None,
1719 is_outbound: true, is_funding_locked: true,
1720 is_usable: true, is_public: true,
1724 // Using the same keys for LN and BTC ids
1726 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1727 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
1729 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
1730 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
1732 let unsigned_announcement = UnsignedChannelAnnouncement {
1734 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1738 bitcoin_key_1: node_id_1,
1739 bitcoin_key_2: node_id_2,
1740 excess_data: Vec::new(),
1743 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1744 let valid_announcement = ChannelAnnouncement {
1745 node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1746 node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1747 bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1748 bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1749 contents: unsigned_announcement.clone(),
1751 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
1752 Ok(res) => assert!(res),
1758 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1759 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
1761 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
1762 let valid_channel_update = ChannelUpdate {
1763 signature: secp_ctx.sign(&msghash, node_privkey),
1764 contents: update.clone()
1767 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
1768 Ok(res) => assert!(res),
1773 fn add_or_update_node(
1774 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1775 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
1777 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
1778 let unsigned_announcement = UnsignedNodeAnnouncement {
1784 addresses: Vec::new(),
1785 excess_address_data: Vec::new(),
1786 excess_data: Vec::new(),
1788 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1789 let valid_announcement = NodeAnnouncement {
1790 signature: secp_ctx.sign(&msghash, node_privkey),
1791 contents: unsigned_announcement.clone()
1794 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
1800 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
1801 let privkeys: Vec<SecretKey> = (2..10).map(|i| {
1802 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
1805 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
1807 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
1808 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
1810 (our_privkey, our_id, privkeys, pubkeys)
1813 fn id_to_feature_flags(id: u8) -> Vec<u8> {
1814 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1815 // test for it later.
1816 let idx = (id - 1) * 2 + 1;
1818 vec![1 << (idx - 8*3), 0, 0, 0]
1819 } else if idx > 8*2 {
1820 vec![1 << (idx - 8*2), 0, 0]
1821 } else if idx > 8*1 {
1822 vec![1 << (idx - 8*1), 0]
1828 fn build_graph() -> (
1830 sync::Arc<NetworkGraph>,
1831 NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
1832 sync::Arc<test_utils::TestChainSource>,
1833 sync::Arc<test_utils::TestLogger>,
1835 let secp_ctx = Secp256k1::new();
1836 let logger = Arc::new(test_utils::TestLogger::new());
1837 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
1838 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
1839 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
1840 // Build network from our_id to node6:
1842 // -1(1)2- node0 -1(3)2-
1844 // our_id -1(12)2- node7 -1(13)2--- node2
1846 // -1(2)2- node1 -1(4)2-
1849 // chan1 1-to-2: disabled
1850 // chan1 2-to-1: enabled, 0 fee
1852 // chan2 1-to-2: enabled, ignored fee
1853 // chan2 2-to-1: enabled, 0 fee
1855 // chan3 1-to-2: enabled, 0 fee
1856 // chan3 2-to-1: enabled, 100 msat fee
1858 // chan4 1-to-2: enabled, 100% fee
1859 // chan4 2-to-1: enabled, 0 fee
1861 // chan12 1-to-2: enabled, ignored fee
1862 // chan12 2-to-1: enabled, 0 fee
1864 // chan13 1-to-2: enabled, 200% fee
1865 // chan13 2-to-1: enabled, 0 fee
1868 // -1(5)2- node3 -1(8)2--
1872 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
1874 // -1(7)2- node5 -1(10)2-
1876 // Channels 5, 8, 9 and 10 are private channels.
1878 // chan5 1-to-2: enabled, 100 msat fee
1879 // chan5 2-to-1: enabled, 0 fee
1881 // chan6 1-to-2: enabled, 0 fee
1882 // chan6 2-to-1: enabled, 0 fee
1884 // chan7 1-to-2: enabled, 100% fee
1885 // chan7 2-to-1: enabled, 0 fee
1887 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
1888 // chan8 2-to-1: enabled, 0 fee
1890 // chan9 1-to-2: enabled, 1001 msat fee
1891 // chan9 2-to-1: enabled, 0 fee
1893 // chan10 1-to-2: enabled, 0 fee
1894 // chan10 2-to-1: enabled, 0 fee
1896 // chan11 1-to-2: enabled, 0 fee
1897 // chan11 2-to-1: enabled, 0 fee
1899 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
1901 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
1902 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1903 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1904 short_channel_id: 1,
1907 cltv_expiry_delta: 0,
1908 htlc_minimum_msat: 0,
1909 htlc_maximum_msat: OptionalField::Absent,
1911 fee_proportional_millionths: 0,
1912 excess_data: Vec::new()
1915 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
1917 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
1918 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1919 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1920 short_channel_id: 2,
1923 cltv_expiry_delta: (5 << 4) | 3,
1924 htlc_minimum_msat: 0,
1925 htlc_maximum_msat: OptionalField::Absent,
1926 fee_base_msat: u32::max_value(),
1927 fee_proportional_millionths: u32::max_value(),
1928 excess_data: Vec::new()
1930 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
1931 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1932 short_channel_id: 2,
1935 cltv_expiry_delta: 0,
1936 htlc_minimum_msat: 0,
1937 htlc_maximum_msat: OptionalField::Absent,
1939 fee_proportional_millionths: 0,
1940 excess_data: Vec::new()
1943 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
1945 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
1946 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1947 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1948 short_channel_id: 12,
1951 cltv_expiry_delta: (5 << 4) | 3,
1952 htlc_minimum_msat: 0,
1953 htlc_maximum_msat: OptionalField::Absent,
1954 fee_base_msat: u32::max_value(),
1955 fee_proportional_millionths: u32::max_value(),
1956 excess_data: Vec::new()
1958 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
1959 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1960 short_channel_id: 12,
1963 cltv_expiry_delta: 0,
1964 htlc_minimum_msat: 0,
1965 htlc_maximum_msat: OptionalField::Absent,
1967 fee_proportional_millionths: 0,
1968 excess_data: Vec::new()
1971 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
1973 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
1974 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1975 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1976 short_channel_id: 3,
1979 cltv_expiry_delta: (3 << 4) | 1,
1980 htlc_minimum_msat: 0,
1981 htlc_maximum_msat: OptionalField::Absent,
1983 fee_proportional_millionths: 0,
1984 excess_data: Vec::new()
1986 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
1987 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1988 short_channel_id: 3,
1991 cltv_expiry_delta: (3 << 4) | 2,
1992 htlc_minimum_msat: 0,
1993 htlc_maximum_msat: OptionalField::Absent,
1995 fee_proportional_millionths: 0,
1996 excess_data: Vec::new()
1999 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2000 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2001 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2002 short_channel_id: 4,
2005 cltv_expiry_delta: (4 << 4) | 1,
2006 htlc_minimum_msat: 0,
2007 htlc_maximum_msat: OptionalField::Absent,
2009 fee_proportional_millionths: 1000000,
2010 excess_data: Vec::new()
2012 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2013 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2014 short_channel_id: 4,
2017 cltv_expiry_delta: (4 << 4) | 2,
2018 htlc_minimum_msat: 0,
2019 htlc_maximum_msat: OptionalField::Absent,
2021 fee_proportional_millionths: 0,
2022 excess_data: Vec::new()
2025 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2026 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2027 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2028 short_channel_id: 13,
2031 cltv_expiry_delta: (13 << 4) | 1,
2032 htlc_minimum_msat: 0,
2033 htlc_maximum_msat: OptionalField::Absent,
2035 fee_proportional_millionths: 2000000,
2036 excess_data: Vec::new()
2038 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2039 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2040 short_channel_id: 13,
2043 cltv_expiry_delta: (13 << 4) | 2,
2044 htlc_minimum_msat: 0,
2045 htlc_maximum_msat: OptionalField::Absent,
2047 fee_proportional_millionths: 0,
2048 excess_data: Vec::new()
2051 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2053 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2054 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2055 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2056 short_channel_id: 6,
2059 cltv_expiry_delta: (6 << 4) | 1,
2060 htlc_minimum_msat: 0,
2061 htlc_maximum_msat: OptionalField::Absent,
2063 fee_proportional_millionths: 0,
2064 excess_data: Vec::new()
2066 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2067 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2068 short_channel_id: 6,
2071 cltv_expiry_delta: (6 << 4) | 2,
2072 htlc_minimum_msat: 0,
2073 htlc_maximum_msat: OptionalField::Absent,
2075 fee_proportional_millionths: 0,
2076 excess_data: Vec::new(),
2079 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2080 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2081 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2082 short_channel_id: 11,
2085 cltv_expiry_delta: (11 << 4) | 1,
2086 htlc_minimum_msat: 0,
2087 htlc_maximum_msat: OptionalField::Absent,
2089 fee_proportional_millionths: 0,
2090 excess_data: Vec::new()
2092 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2093 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2094 short_channel_id: 11,
2097 cltv_expiry_delta: (11 << 4) | 2,
2098 htlc_minimum_msat: 0,
2099 htlc_maximum_msat: OptionalField::Absent,
2101 fee_proportional_millionths: 0,
2102 excess_data: Vec::new()
2105 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2107 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2109 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2110 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2111 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2112 short_channel_id: 7,
2115 cltv_expiry_delta: (7 << 4) | 1,
2116 htlc_minimum_msat: 0,
2117 htlc_maximum_msat: OptionalField::Absent,
2119 fee_proportional_millionths: 1000000,
2120 excess_data: Vec::new()
2122 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2123 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2124 short_channel_id: 7,
2127 cltv_expiry_delta: (7 << 4) | 2,
2128 htlc_minimum_msat: 0,
2129 htlc_maximum_msat: OptionalField::Absent,
2131 fee_proportional_millionths: 0,
2132 excess_data: Vec::new()
2135 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2137 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
2141 fn simple_route_test() {
2142 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2143 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2144 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2145 let scorer = test_utils::TestScorer::with_penalty(0);
2146 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2147 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2149 // Simple route to 2 via 1
2151 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 0, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2152 assert_eq!(err, "Cannot send a payment of 0 msat");
2153 } else { panic!(); }
2155 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2156 assert_eq!(route.paths[0].len(), 2);
2158 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2159 assert_eq!(route.paths[0][0].short_channel_id, 2);
2160 assert_eq!(route.paths[0][0].fee_msat, 100);
2161 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2162 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2163 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2165 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2166 assert_eq!(route.paths[0][1].short_channel_id, 4);
2167 assert_eq!(route.paths[0][1].fee_msat, 100);
2168 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2169 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2170 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2174 fn invalid_first_hop_test() {
2175 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2176 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2177 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2178 let scorer = test_utils::TestScorer::with_penalty(0);
2179 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2180 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2182 // Simple route to 2 via 1
2184 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2186 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2187 get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2188 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2189 } else { panic!(); }
2191 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2192 assert_eq!(route.paths[0].len(), 2);
2196 fn htlc_minimum_test() {
2197 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2198 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2199 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2200 let scorer = test_utils::TestScorer::with_penalty(0);
2201 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2202 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2204 // Simple route to 2 via 1
2206 // Disable other paths
2207 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2208 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2209 short_channel_id: 12,
2211 flags: 2, // to disable
2212 cltv_expiry_delta: 0,
2213 htlc_minimum_msat: 0,
2214 htlc_maximum_msat: OptionalField::Absent,
2216 fee_proportional_millionths: 0,
2217 excess_data: Vec::new()
2219 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2220 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2221 short_channel_id: 3,
2223 flags: 2, // to disable
2224 cltv_expiry_delta: 0,
2225 htlc_minimum_msat: 0,
2226 htlc_maximum_msat: OptionalField::Absent,
2228 fee_proportional_millionths: 0,
2229 excess_data: Vec::new()
2231 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2232 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2233 short_channel_id: 13,
2235 flags: 2, // to disable
2236 cltv_expiry_delta: 0,
2237 htlc_minimum_msat: 0,
2238 htlc_maximum_msat: OptionalField::Absent,
2240 fee_proportional_millionths: 0,
2241 excess_data: Vec::new()
2243 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2244 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2245 short_channel_id: 6,
2247 flags: 2, // to disable
2248 cltv_expiry_delta: 0,
2249 htlc_minimum_msat: 0,
2250 htlc_maximum_msat: OptionalField::Absent,
2252 fee_proportional_millionths: 0,
2253 excess_data: Vec::new()
2255 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2256 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2257 short_channel_id: 7,
2259 flags: 2, // to disable
2260 cltv_expiry_delta: 0,
2261 htlc_minimum_msat: 0,
2262 htlc_maximum_msat: OptionalField::Absent,
2264 fee_proportional_millionths: 0,
2265 excess_data: Vec::new()
2268 // Check against amount_to_transfer_over_msat.
2269 // Set minimal HTLC of 200_000_000 msat.
2270 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2271 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2272 short_channel_id: 2,
2275 cltv_expiry_delta: 0,
2276 htlc_minimum_msat: 200_000_000,
2277 htlc_maximum_msat: OptionalField::Absent,
2279 fee_proportional_millionths: 0,
2280 excess_data: Vec::new()
2283 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2285 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2286 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2287 short_channel_id: 4,
2290 cltv_expiry_delta: 0,
2291 htlc_minimum_msat: 0,
2292 htlc_maximum_msat: OptionalField::Present(199_999_999),
2294 fee_proportional_millionths: 0,
2295 excess_data: Vec::new()
2298 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2299 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2300 assert_eq!(err, "Failed to find a path to the given destination");
2301 } else { panic!(); }
2303 // Lift the restriction on the first hop.
2304 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2306 short_channel_id: 2,
2309 cltv_expiry_delta: 0,
2310 htlc_minimum_msat: 0,
2311 htlc_maximum_msat: OptionalField::Absent,
2313 fee_proportional_millionths: 0,
2314 excess_data: Vec::new()
2317 // A payment above the minimum should pass
2318 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 199_999_999, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2319 assert_eq!(route.paths[0].len(), 2);
2323 fn htlc_minimum_overpay_test() {
2324 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2325 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2326 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2327 let scorer = test_utils::TestScorer::with_penalty(0);
2328 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2329 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2331 // A route to node#2 via two paths.
2332 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2333 // Thus, they can't send 60 without overpaying.
2334 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2335 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2336 short_channel_id: 2,
2339 cltv_expiry_delta: 0,
2340 htlc_minimum_msat: 35_000,
2341 htlc_maximum_msat: OptionalField::Present(40_000),
2343 fee_proportional_millionths: 0,
2344 excess_data: Vec::new()
2346 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2347 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2348 short_channel_id: 12,
2351 cltv_expiry_delta: 0,
2352 htlc_minimum_msat: 35_000,
2353 htlc_maximum_msat: OptionalField::Present(40_000),
2355 fee_proportional_millionths: 0,
2356 excess_data: Vec::new()
2360 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2361 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2362 short_channel_id: 13,
2365 cltv_expiry_delta: 0,
2366 htlc_minimum_msat: 0,
2367 htlc_maximum_msat: OptionalField::Absent,
2369 fee_proportional_millionths: 0,
2370 excess_data: Vec::new()
2372 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2373 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2374 short_channel_id: 4,
2377 cltv_expiry_delta: 0,
2378 htlc_minimum_msat: 0,
2379 htlc_maximum_msat: OptionalField::Absent,
2381 fee_proportional_millionths: 0,
2382 excess_data: Vec::new()
2385 // Disable other paths
2386 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2387 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2388 short_channel_id: 1,
2390 flags: 2, // to disable
2391 cltv_expiry_delta: 0,
2392 htlc_minimum_msat: 0,
2393 htlc_maximum_msat: OptionalField::Absent,
2395 fee_proportional_millionths: 0,
2396 excess_data: Vec::new()
2399 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2400 // Overpay fees to hit htlc_minimum_msat.
2401 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2402 // TODO: this could be better balanced to overpay 10k and not 15k.
2403 assert_eq!(overpaid_fees, 15_000);
2405 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2406 // while taking even more fee to match htlc_minimum_msat.
2407 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2408 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2409 short_channel_id: 12,
2412 cltv_expiry_delta: 0,
2413 htlc_minimum_msat: 65_000,
2414 htlc_maximum_msat: OptionalField::Present(80_000),
2416 fee_proportional_millionths: 0,
2417 excess_data: Vec::new()
2419 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2420 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2421 short_channel_id: 2,
2424 cltv_expiry_delta: 0,
2425 htlc_minimum_msat: 0,
2426 htlc_maximum_msat: OptionalField::Absent,
2428 fee_proportional_millionths: 0,
2429 excess_data: Vec::new()
2431 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2432 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2433 short_channel_id: 4,
2436 cltv_expiry_delta: 0,
2437 htlc_minimum_msat: 0,
2438 htlc_maximum_msat: OptionalField::Absent,
2440 fee_proportional_millionths: 100_000,
2441 excess_data: Vec::new()
2444 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2445 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2446 assert_eq!(route.paths.len(), 1);
2447 assert_eq!(route.paths[0][0].short_channel_id, 12);
2448 let fees = route.paths[0][0].fee_msat;
2449 assert_eq!(fees, 5_000);
2451 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2452 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2453 // the other channel.
2454 assert_eq!(route.paths.len(), 1);
2455 assert_eq!(route.paths[0][0].short_channel_id, 2);
2456 let fees = route.paths[0][0].fee_msat;
2457 assert_eq!(fees, 5_000);
2461 fn disable_channels_test() {
2462 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2463 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2464 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2465 let scorer = test_utils::TestScorer::with_penalty(0);
2466 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2467 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2469 // // Disable channels 4 and 12 by flags=2
2470 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2471 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2472 short_channel_id: 4,
2474 flags: 2, // to disable
2475 cltv_expiry_delta: 0,
2476 htlc_minimum_msat: 0,
2477 htlc_maximum_msat: OptionalField::Absent,
2479 fee_proportional_millionths: 0,
2480 excess_data: Vec::new()
2482 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2483 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2484 short_channel_id: 12,
2486 flags: 2, // to disable
2487 cltv_expiry_delta: 0,
2488 htlc_minimum_msat: 0,
2489 htlc_maximum_msat: OptionalField::Absent,
2491 fee_proportional_millionths: 0,
2492 excess_data: Vec::new()
2495 // If all the channels require some features we don't understand, route should fail
2496 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2497 assert_eq!(err, "Failed to find a path to the given destination");
2498 } else { panic!(); }
2500 // If we specify a channel to node7, that overrides our local channel view and that gets used
2501 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2502 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2503 assert_eq!(route.paths[0].len(), 2);
2505 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2506 assert_eq!(route.paths[0][0].short_channel_id, 42);
2507 assert_eq!(route.paths[0][0].fee_msat, 200);
2508 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2509 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2510 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2512 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2513 assert_eq!(route.paths[0][1].short_channel_id, 13);
2514 assert_eq!(route.paths[0][1].fee_msat, 100);
2515 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2516 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2517 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2521 fn disable_node_test() {
2522 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2523 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2524 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2525 let scorer = test_utils::TestScorer::with_penalty(0);
2526 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2527 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2529 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2530 let mut unknown_features = NodeFeatures::known();
2531 unknown_features.set_unknown_feature_required();
2532 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2533 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2534 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2536 // If all nodes require some features we don't understand, route should fail
2537 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2538 assert_eq!(err, "Failed to find a path to the given destination");
2539 } else { panic!(); }
2541 // If we specify a channel to node7, that overrides our local channel view and that gets used
2542 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2543 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2544 assert_eq!(route.paths[0].len(), 2);
2546 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2547 assert_eq!(route.paths[0][0].short_channel_id, 42);
2548 assert_eq!(route.paths[0][0].fee_msat, 200);
2549 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2550 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2551 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2553 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2554 assert_eq!(route.paths[0][1].short_channel_id, 13);
2555 assert_eq!(route.paths[0][1].fee_msat, 100);
2556 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2557 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2558 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2560 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2561 // naively) assume that the user checked the feature bits on the invoice, which override
2562 // the node_announcement.
2566 fn our_chans_test() {
2567 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2568 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2569 let scorer = test_utils::TestScorer::with_penalty(0);
2570 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2571 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2573 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2574 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2575 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2576 assert_eq!(route.paths[0].len(), 3);
2578 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2579 assert_eq!(route.paths[0][0].short_channel_id, 2);
2580 assert_eq!(route.paths[0][0].fee_msat, 200);
2581 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2582 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2583 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2585 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2586 assert_eq!(route.paths[0][1].short_channel_id, 4);
2587 assert_eq!(route.paths[0][1].fee_msat, 100);
2588 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2589 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2590 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2592 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2593 assert_eq!(route.paths[0][2].short_channel_id, 3);
2594 assert_eq!(route.paths[0][2].fee_msat, 100);
2595 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2596 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2597 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2599 // If we specify a channel to node7, that overrides our local channel view and that gets used
2600 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2601 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2602 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2603 assert_eq!(route.paths[0].len(), 2);
2605 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2606 assert_eq!(route.paths[0][0].short_channel_id, 42);
2607 assert_eq!(route.paths[0][0].fee_msat, 200);
2608 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2609 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2610 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2612 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2613 assert_eq!(route.paths[0][1].short_channel_id, 13);
2614 assert_eq!(route.paths[0][1].fee_msat, 100);
2615 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2616 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2617 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2620 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2621 let zero_fees = RoutingFees {
2623 proportional_millionths: 0,
2625 vec![RouteHint(vec![RouteHintHop {
2626 src_node_id: nodes[3],
2627 short_channel_id: 8,
2629 cltv_expiry_delta: (8 << 4) | 1,
2630 htlc_minimum_msat: None,
2631 htlc_maximum_msat: None,
2633 ]), RouteHint(vec![RouteHintHop {
2634 src_node_id: nodes[4],
2635 short_channel_id: 9,
2638 proportional_millionths: 0,
2640 cltv_expiry_delta: (9 << 4) | 1,
2641 htlc_minimum_msat: None,
2642 htlc_maximum_msat: None,
2643 }]), RouteHint(vec![RouteHintHop {
2644 src_node_id: nodes[5],
2645 short_channel_id: 10,
2647 cltv_expiry_delta: (10 << 4) | 1,
2648 htlc_minimum_msat: None,
2649 htlc_maximum_msat: None,
2653 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2654 let zero_fees = RoutingFees {
2656 proportional_millionths: 0,
2658 vec![RouteHint(vec![RouteHintHop {
2659 src_node_id: nodes[2],
2660 short_channel_id: 5,
2663 proportional_millionths: 0,
2665 cltv_expiry_delta: (5 << 4) | 1,
2666 htlc_minimum_msat: None,
2667 htlc_maximum_msat: None,
2669 src_node_id: nodes[3],
2670 short_channel_id: 8,
2672 cltv_expiry_delta: (8 << 4) | 1,
2673 htlc_minimum_msat: None,
2674 htlc_maximum_msat: None,
2676 ]), RouteHint(vec![RouteHintHop {
2677 src_node_id: nodes[4],
2678 short_channel_id: 9,
2681 proportional_millionths: 0,
2683 cltv_expiry_delta: (9 << 4) | 1,
2684 htlc_minimum_msat: None,
2685 htlc_maximum_msat: None,
2686 }]), RouteHint(vec![RouteHintHop {
2687 src_node_id: nodes[5],
2688 short_channel_id: 10,
2690 cltv_expiry_delta: (10 << 4) | 1,
2691 htlc_minimum_msat: None,
2692 htlc_maximum_msat: None,
2697 fn partial_route_hint_test() {
2698 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2699 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2700 let scorer = test_utils::TestScorer::with_penalty(0);
2701 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2702 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2704 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2705 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2706 // RouteHint may be partially used by the algo to build the best path.
2708 // First check that last hop can't have its source as the payee.
2709 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2710 src_node_id: nodes[6],
2711 short_channel_id: 8,
2714 proportional_millionths: 0,
2716 cltv_expiry_delta: (8 << 4) | 1,
2717 htlc_minimum_msat: None,
2718 htlc_maximum_msat: None,
2721 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2722 invalid_last_hops.push(invalid_last_hop);
2724 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2725 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2726 assert_eq!(err, "Route hint cannot have the payee as the source.");
2727 } else { panic!(); }
2730 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2731 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2732 assert_eq!(route.paths[0].len(), 5);
2734 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2735 assert_eq!(route.paths[0][0].short_channel_id, 2);
2736 assert_eq!(route.paths[0][0].fee_msat, 100);
2737 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2738 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2739 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2741 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2742 assert_eq!(route.paths[0][1].short_channel_id, 4);
2743 assert_eq!(route.paths[0][1].fee_msat, 0);
2744 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2745 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2746 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2748 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2749 assert_eq!(route.paths[0][2].short_channel_id, 6);
2750 assert_eq!(route.paths[0][2].fee_msat, 0);
2751 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2752 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2753 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2755 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2756 assert_eq!(route.paths[0][3].short_channel_id, 11);
2757 assert_eq!(route.paths[0][3].fee_msat, 0);
2758 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2759 // If we have a peer in the node map, we'll use their features here since we don't have
2760 // a way of figuring out their features from the invoice:
2761 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2762 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2764 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2765 assert_eq!(route.paths[0][4].short_channel_id, 8);
2766 assert_eq!(route.paths[0][4].fee_msat, 100);
2767 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2768 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2769 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2772 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2773 let zero_fees = RoutingFees {
2775 proportional_millionths: 0,
2777 vec![RouteHint(vec![RouteHintHop {
2778 src_node_id: nodes[3],
2779 short_channel_id: 8,
2781 cltv_expiry_delta: (8 << 4) | 1,
2782 htlc_minimum_msat: None,
2783 htlc_maximum_msat: None,
2784 }]), RouteHint(vec![
2786 ]), RouteHint(vec![RouteHintHop {
2787 src_node_id: nodes[5],
2788 short_channel_id: 10,
2790 cltv_expiry_delta: (10 << 4) | 1,
2791 htlc_minimum_msat: None,
2792 htlc_maximum_msat: None,
2797 fn ignores_empty_last_hops_test() {
2798 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2799 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2800 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2801 let scorer = test_utils::TestScorer::with_penalty(0);
2802 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2803 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2805 // Test handling of an empty RouteHint passed in Invoice.
2807 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2808 assert_eq!(route.paths[0].len(), 5);
2810 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2811 assert_eq!(route.paths[0][0].short_channel_id, 2);
2812 assert_eq!(route.paths[0][0].fee_msat, 100);
2813 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2814 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2815 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2817 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2818 assert_eq!(route.paths[0][1].short_channel_id, 4);
2819 assert_eq!(route.paths[0][1].fee_msat, 0);
2820 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2821 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2822 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2824 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2825 assert_eq!(route.paths[0][2].short_channel_id, 6);
2826 assert_eq!(route.paths[0][2].fee_msat, 0);
2827 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2828 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2829 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2831 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2832 assert_eq!(route.paths[0][3].short_channel_id, 11);
2833 assert_eq!(route.paths[0][3].fee_msat, 0);
2834 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2835 // If we have a peer in the node map, we'll use their features here since we don't have
2836 // a way of figuring out their features from the invoice:
2837 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2838 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2840 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2841 assert_eq!(route.paths[0][4].short_channel_id, 8);
2842 assert_eq!(route.paths[0][4].fee_msat, 100);
2843 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2844 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2845 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2848 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2850 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2851 let zero_fees = RoutingFees {
2853 proportional_millionths: 0,
2855 vec![RouteHint(vec![RouteHintHop {
2856 src_node_id: hint_hops[0],
2857 short_channel_id: 0xff00,
2860 proportional_millionths: 0,
2862 cltv_expiry_delta: (5 << 4) | 1,
2863 htlc_minimum_msat: None,
2864 htlc_maximum_msat: None,
2866 src_node_id: hint_hops[1],
2867 short_channel_id: 0xff01,
2869 cltv_expiry_delta: (8 << 4) | 1,
2870 htlc_minimum_msat: None,
2871 htlc_maximum_msat: None,
2876 fn multi_hint_last_hops_test() {
2877 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2878 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2879 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2880 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2881 let scorer = test_utils::TestScorer::with_penalty(0);
2882 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2883 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2884 // Test through channels 2, 3, 0xff00, 0xff01.
2885 // Test shows that multiple hop hints are considered.
2887 // Disabling channels 6 & 7 by flags=2
2888 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2889 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2890 short_channel_id: 6,
2892 flags: 2, // to disable
2893 cltv_expiry_delta: 0,
2894 htlc_minimum_msat: 0,
2895 htlc_maximum_msat: OptionalField::Absent,
2897 fee_proportional_millionths: 0,
2898 excess_data: Vec::new()
2900 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2901 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2902 short_channel_id: 7,
2904 flags: 2, // to disable
2905 cltv_expiry_delta: 0,
2906 htlc_minimum_msat: 0,
2907 htlc_maximum_msat: OptionalField::Absent,
2909 fee_proportional_millionths: 0,
2910 excess_data: Vec::new()
2913 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2914 assert_eq!(route.paths[0].len(), 4);
2916 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2917 assert_eq!(route.paths[0][0].short_channel_id, 2);
2918 assert_eq!(route.paths[0][0].fee_msat, 200);
2919 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2920 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2921 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2923 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2924 assert_eq!(route.paths[0][1].short_channel_id, 4);
2925 assert_eq!(route.paths[0][1].fee_msat, 100);
2926 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2927 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2928 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2930 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2931 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2932 assert_eq!(route.paths[0][2].fee_msat, 0);
2933 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2934 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2935 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2937 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2938 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2939 assert_eq!(route.paths[0][3].fee_msat, 100);
2940 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2941 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
2942 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2946 fn private_multi_hint_last_hops_test() {
2947 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2948 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2950 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
2951 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
2953 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
2954 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2955 let scorer = test_utils::TestScorer::with_penalty(0);
2956 // Test through channels 2, 3, 0xff00, 0xff01.
2957 // Test shows that multiple hop hints are considered.
2959 // Disabling channels 6 & 7 by flags=2
2960 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2962 short_channel_id: 6,
2964 flags: 2, // to disable
2965 cltv_expiry_delta: 0,
2966 htlc_minimum_msat: 0,
2967 htlc_maximum_msat: OptionalField::Absent,
2969 fee_proportional_millionths: 0,
2970 excess_data: Vec::new()
2972 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2973 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2974 short_channel_id: 7,
2976 flags: 2, // to disable
2977 cltv_expiry_delta: 0,
2978 htlc_minimum_msat: 0,
2979 htlc_maximum_msat: OptionalField::Absent,
2981 fee_proportional_millionths: 0,
2982 excess_data: Vec::new()
2985 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
2986 assert_eq!(route.paths[0].len(), 4);
2988 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2989 assert_eq!(route.paths[0][0].short_channel_id, 2);
2990 assert_eq!(route.paths[0][0].fee_msat, 200);
2991 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2992 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2993 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2995 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2996 assert_eq!(route.paths[0][1].short_channel_id, 4);
2997 assert_eq!(route.paths[0][1].fee_msat, 100);
2998 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2999 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3000 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3002 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3003 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3004 assert_eq!(route.paths[0][2].fee_msat, 0);
3005 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3006 assert_eq!(route.paths[0][2].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3007 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3009 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3010 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3011 assert_eq!(route.paths[0][3].fee_msat, 100);
3012 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3013 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3014 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3017 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3018 let zero_fees = RoutingFees {
3020 proportional_millionths: 0,
3022 vec![RouteHint(vec![RouteHintHop {
3023 src_node_id: nodes[4],
3024 short_channel_id: 11,
3026 cltv_expiry_delta: (11 << 4) | 1,
3027 htlc_minimum_msat: None,
3028 htlc_maximum_msat: None,
3030 src_node_id: nodes[3],
3031 short_channel_id: 8,
3033 cltv_expiry_delta: (8 << 4) | 1,
3034 htlc_minimum_msat: None,
3035 htlc_maximum_msat: None,
3036 }]), RouteHint(vec![RouteHintHop {
3037 src_node_id: nodes[4],
3038 short_channel_id: 9,
3041 proportional_millionths: 0,
3043 cltv_expiry_delta: (9 << 4) | 1,
3044 htlc_minimum_msat: None,
3045 htlc_maximum_msat: None,
3046 }]), RouteHint(vec![RouteHintHop {
3047 src_node_id: nodes[5],
3048 short_channel_id: 10,
3050 cltv_expiry_delta: (10 << 4) | 1,
3051 htlc_minimum_msat: None,
3052 htlc_maximum_msat: None,
3057 fn last_hops_with_public_channel_test() {
3058 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3059 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3060 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3061 let scorer = test_utils::TestScorer::with_penalty(0);
3062 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3063 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3064 // This test shows that public routes can be present in the invoice
3065 // which would be handled in the same manner.
3067 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3068 assert_eq!(route.paths[0].len(), 5);
3070 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3071 assert_eq!(route.paths[0][0].short_channel_id, 2);
3072 assert_eq!(route.paths[0][0].fee_msat, 100);
3073 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3074 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3075 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3077 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3078 assert_eq!(route.paths[0][1].short_channel_id, 4);
3079 assert_eq!(route.paths[0][1].fee_msat, 0);
3080 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3081 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3082 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3084 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3085 assert_eq!(route.paths[0][2].short_channel_id, 6);
3086 assert_eq!(route.paths[0][2].fee_msat, 0);
3087 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3088 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3089 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3091 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3092 assert_eq!(route.paths[0][3].short_channel_id, 11);
3093 assert_eq!(route.paths[0][3].fee_msat, 0);
3094 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3095 // If we have a peer in the node map, we'll use their features here since we don't have
3096 // a way of figuring out their features from the invoice:
3097 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3098 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3100 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3101 assert_eq!(route.paths[0][4].short_channel_id, 8);
3102 assert_eq!(route.paths[0][4].fee_msat, 100);
3103 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3104 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3105 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3109 fn our_chans_last_hop_connect_test() {
3110 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3111 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3112 let scorer = test_utils::TestScorer::with_penalty(0);
3113 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3114 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3116 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3117 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3118 let mut last_hops = last_hops(&nodes);
3119 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3120 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3121 assert_eq!(route.paths[0].len(), 2);
3123 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3124 assert_eq!(route.paths[0][0].short_channel_id, 42);
3125 assert_eq!(route.paths[0][0].fee_msat, 0);
3126 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3127 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3128 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3130 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3131 assert_eq!(route.paths[0][1].short_channel_id, 8);
3132 assert_eq!(route.paths[0][1].fee_msat, 100);
3133 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3134 assert_eq!(route.paths[0][1].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3135 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3137 last_hops[0].0[0].fees.base_msat = 1000;
3139 // Revert to via 6 as the fee on 8 goes up
3140 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3141 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3142 assert_eq!(route.paths[0].len(), 4);
3144 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3145 assert_eq!(route.paths[0][0].short_channel_id, 2);
3146 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3147 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3148 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3149 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3151 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3152 assert_eq!(route.paths[0][1].short_channel_id, 4);
3153 assert_eq!(route.paths[0][1].fee_msat, 100);
3154 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3155 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3156 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3158 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3159 assert_eq!(route.paths[0][2].short_channel_id, 7);
3160 assert_eq!(route.paths[0][2].fee_msat, 0);
3161 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3162 // If we have a peer in the node map, we'll use their features here since we don't have
3163 // a way of figuring out their features from the invoice:
3164 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3165 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3167 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3168 assert_eq!(route.paths[0][3].short_channel_id, 10);
3169 assert_eq!(route.paths[0][3].fee_msat, 100);
3170 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3171 assert_eq!(route.paths[0][3].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3172 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3174 // ...but still use 8 for larger payments as 6 has a variable feerate
3175 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3176 assert_eq!(route.paths[0].len(), 5);
3178 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3179 assert_eq!(route.paths[0][0].short_channel_id, 2);
3180 assert_eq!(route.paths[0][0].fee_msat, 3000);
3181 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3182 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3183 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3185 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3186 assert_eq!(route.paths[0][1].short_channel_id, 4);
3187 assert_eq!(route.paths[0][1].fee_msat, 0);
3188 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3189 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3190 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3192 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3193 assert_eq!(route.paths[0][2].short_channel_id, 6);
3194 assert_eq!(route.paths[0][2].fee_msat, 0);
3195 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3196 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3197 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3199 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3200 assert_eq!(route.paths[0][3].short_channel_id, 11);
3201 assert_eq!(route.paths[0][3].fee_msat, 1000);
3202 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3203 // If we have a peer in the node map, we'll use their features here since we don't have
3204 // a way of figuring out their features from the invoice:
3205 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3206 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3208 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3209 assert_eq!(route.paths[0][4].short_channel_id, 8);
3210 assert_eq!(route.paths[0][4].fee_msat, 2000);
3211 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3212 assert_eq!(route.paths[0][4].node_features.le_flags(), &Vec::<u8>::new()); // We dont pass flags in from invoices yet
3213 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3216 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> {
3217 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3218 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3219 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3221 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3222 let last_hops = RouteHint(vec![RouteHintHop {
3223 src_node_id: middle_node_id,
3224 short_channel_id: 8,
3227 proportional_millionths: last_hop_fee_prop,
3229 cltv_expiry_delta: (8 << 4) | 1,
3230 htlc_minimum_msat: None,
3231 htlc_maximum_msat: last_hop_htlc_max,
3233 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3234 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3235 let scorer = test_utils::TestScorer::with_penalty(0);
3236 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3237 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3238 get_route(&source_node_id, &payment_params, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()).read_only(),
3239 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes)
3243 fn unannounced_path_test() {
3244 // We should be able to send a payment to a destination without any help of a routing graph
3245 // if we have a channel with a common counterparty that appears in the first and last hop
3247 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3249 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3250 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3251 assert_eq!(route.paths[0].len(), 2);
3253 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3254 assert_eq!(route.paths[0][0].short_channel_id, 42);
3255 assert_eq!(route.paths[0][0].fee_msat, 1001);
3256 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3257 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3258 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3260 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3261 assert_eq!(route.paths[0][1].short_channel_id, 8);
3262 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3263 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3264 assert_eq!(route.paths[0][1].node_features.le_flags(), &[0; 0]); // We dont pass flags in from invoices yet
3265 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3269 fn overflow_unannounced_path_test_liquidity_underflow() {
3270 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3271 // the last-hop had a fee which overflowed a u64, we'd panic.
3272 // This was due to us adding the first-hop from us unconditionally, causing us to think
3273 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3274 // In this test, we previously hit a subtraction underflow due to having less available
3275 // liquidity at the last hop than 0.
3276 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());
3280 fn overflow_unannounced_path_test_feerate_overflow() {
3281 // This tests for the same case as above, except instead of hitting a subtraction
3282 // underflow, we hit a case where the fee charged at a hop overflowed.
3283 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());
3287 fn available_amount_while_routing_test() {
3288 // Tests whether we choose the correct available channel amount while routing.
3290 let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
3291 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3292 let scorer = test_utils::TestScorer::with_penalty(0);
3293 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3294 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3295 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3297 // We will use a simple single-path route from
3298 // our node to node2 via node0: channels {1, 3}.
3300 // First disable all other paths.
3301 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3302 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3303 short_channel_id: 2,
3306 cltv_expiry_delta: 0,
3307 htlc_minimum_msat: 0,
3308 htlc_maximum_msat: OptionalField::Present(100_000),
3310 fee_proportional_millionths: 0,
3311 excess_data: Vec::new()
3313 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3314 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3315 short_channel_id: 12,
3318 cltv_expiry_delta: 0,
3319 htlc_minimum_msat: 0,
3320 htlc_maximum_msat: OptionalField::Present(100_000),
3322 fee_proportional_millionths: 0,
3323 excess_data: Vec::new()
3326 // Make the first channel (#1) very permissive,
3327 // and we will be testing all limits on the second channel.
3328 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3329 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3330 short_channel_id: 1,
3333 cltv_expiry_delta: 0,
3334 htlc_minimum_msat: 0,
3335 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3337 fee_proportional_millionths: 0,
3338 excess_data: Vec::new()
3341 // First, let's see if routing works if we have absolutely no idea about the available amount.
3342 // In this case, it should be set to 250_000 sats.
3343 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3344 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3345 short_channel_id: 3,
3348 cltv_expiry_delta: 0,
3349 htlc_minimum_msat: 0,
3350 htlc_maximum_msat: OptionalField::Absent,
3352 fee_proportional_millionths: 0,
3353 excess_data: Vec::new()
3357 // Attempt to route more than available results in a failure.
3358 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3359 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3360 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3361 } else { panic!(); }
3365 // Now, attempt to route an exact amount we have should be fine.
3366 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3367 assert_eq!(route.paths.len(), 1);
3368 let path = route.paths.last().unwrap();
3369 assert_eq!(path.len(), 2);
3370 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3371 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3374 // Check that setting outbound_capacity_msat in first_hops limits the channels.
3375 // Disable channel #1 and use another first hop.
3376 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3377 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3378 short_channel_id: 1,
3381 cltv_expiry_delta: 0,
3382 htlc_minimum_msat: 0,
3383 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3385 fee_proportional_millionths: 0,
3386 excess_data: Vec::new()
3389 // Now, limit the first_hop by the outbound_capacity_msat of 200_000 sats.
3390 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3393 // Attempt to route more than available results in a failure.
3394 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3395 &our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3396 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3397 } else { panic!(); }
3401 // Now, attempt to route an exact amount we have should be fine.
3402 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 200_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3403 assert_eq!(route.paths.len(), 1);
3404 let path = route.paths.last().unwrap();
3405 assert_eq!(path.len(), 2);
3406 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3407 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3410 // Enable channel #1 back.
3411 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3412 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3413 short_channel_id: 1,
3416 cltv_expiry_delta: 0,
3417 htlc_minimum_msat: 0,
3418 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3420 fee_proportional_millionths: 0,
3421 excess_data: Vec::new()
3425 // Now let's see if routing works if we know only htlc_maximum_msat.
3426 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3427 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3428 short_channel_id: 3,
3431 cltv_expiry_delta: 0,
3432 htlc_minimum_msat: 0,
3433 htlc_maximum_msat: OptionalField::Present(15_000),
3435 fee_proportional_millionths: 0,
3436 excess_data: Vec::new()
3440 // Attempt to route more than available results in a failure.
3441 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3442 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3443 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3444 } else { panic!(); }
3448 // Now, attempt to route an exact amount we have should be fine.
3449 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3450 assert_eq!(route.paths.len(), 1);
3451 let path = route.paths.last().unwrap();
3452 assert_eq!(path.len(), 2);
3453 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3454 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3457 // Now let's see if routing works if we know only capacity from the UTXO.
3459 // We can't change UTXO capacity on the fly, so we'll disable
3460 // the existing channel and add another one with the capacity we need.
3461 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3462 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3463 short_channel_id: 3,
3466 cltv_expiry_delta: 0,
3467 htlc_minimum_msat: 0,
3468 htlc_maximum_msat: OptionalField::Absent,
3470 fee_proportional_millionths: 0,
3471 excess_data: Vec::new()
3474 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3475 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3476 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3477 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3478 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3480 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3481 net_graph_msg_handler.add_chain_access(Some(chain_monitor));
3483 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3484 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3485 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3486 short_channel_id: 333,
3489 cltv_expiry_delta: (3 << 4) | 1,
3490 htlc_minimum_msat: 0,
3491 htlc_maximum_msat: OptionalField::Absent,
3493 fee_proportional_millionths: 0,
3494 excess_data: Vec::new()
3496 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3497 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3498 short_channel_id: 333,
3501 cltv_expiry_delta: (3 << 4) | 2,
3502 htlc_minimum_msat: 0,
3503 htlc_maximum_msat: OptionalField::Absent,
3505 fee_proportional_millionths: 0,
3506 excess_data: Vec::new()
3510 // Attempt to route more than available results in a failure.
3511 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3512 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3513 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3514 } else { panic!(); }
3518 // Now, attempt to route an exact amount we have should be fine.
3519 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3520 assert_eq!(route.paths.len(), 1);
3521 let path = route.paths.last().unwrap();
3522 assert_eq!(path.len(), 2);
3523 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3524 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3527 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3528 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3530 short_channel_id: 333,
3533 cltv_expiry_delta: 0,
3534 htlc_minimum_msat: 0,
3535 htlc_maximum_msat: OptionalField::Present(10_000),
3537 fee_proportional_millionths: 0,
3538 excess_data: Vec::new()
3542 // Attempt to route more than available results in a failure.
3543 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3544 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3545 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3546 } else { panic!(); }
3550 // Now, attempt to route an exact amount we have should be fine.
3551 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3552 assert_eq!(route.paths.len(), 1);
3553 let path = route.paths.last().unwrap();
3554 assert_eq!(path.len(), 2);
3555 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3556 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3561 fn available_liquidity_last_hop_test() {
3562 // Check that available liquidity properly limits the path even when only
3563 // one of the latter hops is limited.
3564 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3565 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3566 let scorer = test_utils::TestScorer::with_penalty(0);
3567 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3568 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3569 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3571 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3572 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3573 // Total capacity: 50 sats.
3575 // Disable other potential paths.
3576 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3577 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3578 short_channel_id: 2,
3581 cltv_expiry_delta: 0,
3582 htlc_minimum_msat: 0,
3583 htlc_maximum_msat: OptionalField::Present(100_000),
3585 fee_proportional_millionths: 0,
3586 excess_data: Vec::new()
3588 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3589 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3590 short_channel_id: 7,
3593 cltv_expiry_delta: 0,
3594 htlc_minimum_msat: 0,
3595 htlc_maximum_msat: OptionalField::Present(100_000),
3597 fee_proportional_millionths: 0,
3598 excess_data: Vec::new()
3603 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3604 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3605 short_channel_id: 12,
3608 cltv_expiry_delta: 0,
3609 htlc_minimum_msat: 0,
3610 htlc_maximum_msat: OptionalField::Present(100_000),
3612 fee_proportional_millionths: 0,
3613 excess_data: Vec::new()
3615 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3616 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3617 short_channel_id: 13,
3620 cltv_expiry_delta: 0,
3621 htlc_minimum_msat: 0,
3622 htlc_maximum_msat: OptionalField::Present(100_000),
3624 fee_proportional_millionths: 0,
3625 excess_data: Vec::new()
3628 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3629 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3630 short_channel_id: 6,
3633 cltv_expiry_delta: 0,
3634 htlc_minimum_msat: 0,
3635 htlc_maximum_msat: OptionalField::Present(50_000),
3637 fee_proportional_millionths: 0,
3638 excess_data: Vec::new()
3640 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3641 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3642 short_channel_id: 11,
3645 cltv_expiry_delta: 0,
3646 htlc_minimum_msat: 0,
3647 htlc_maximum_msat: OptionalField::Present(100_000),
3649 fee_proportional_millionths: 0,
3650 excess_data: Vec::new()
3653 // Attempt to route more than available results in a failure.
3654 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3655 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3656 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3657 } else { panic!(); }
3661 // Now, attempt to route 49 sats (just a bit below the capacity).
3662 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3663 assert_eq!(route.paths.len(), 1);
3664 let mut total_amount_paid_msat = 0;
3665 for path in &route.paths {
3666 assert_eq!(path.len(), 4);
3667 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3668 total_amount_paid_msat += path.last().unwrap().fee_msat;
3670 assert_eq!(total_amount_paid_msat, 49_000);
3674 // Attempt to route an exact amount is also fine
3675 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3676 assert_eq!(route.paths.len(), 1);
3677 let mut total_amount_paid_msat = 0;
3678 for path in &route.paths {
3679 assert_eq!(path.len(), 4);
3680 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3681 total_amount_paid_msat += path.last().unwrap().fee_msat;
3683 assert_eq!(total_amount_paid_msat, 50_000);
3688 fn ignore_fee_first_hop_test() {
3689 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3690 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3691 let scorer = test_utils::TestScorer::with_penalty(0);
3692 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3693 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3694 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3696 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3697 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3698 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3699 short_channel_id: 1,
3702 cltv_expiry_delta: 0,
3703 htlc_minimum_msat: 0,
3704 htlc_maximum_msat: OptionalField::Present(100_000),
3705 fee_base_msat: 1_000_000,
3706 fee_proportional_millionths: 0,
3707 excess_data: Vec::new()
3709 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3710 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3711 short_channel_id: 3,
3714 cltv_expiry_delta: 0,
3715 htlc_minimum_msat: 0,
3716 htlc_maximum_msat: OptionalField::Present(50_000),
3718 fee_proportional_millionths: 0,
3719 excess_data: Vec::new()
3723 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3724 assert_eq!(route.paths.len(), 1);
3725 let mut total_amount_paid_msat = 0;
3726 for path in &route.paths {
3727 assert_eq!(path.len(), 2);
3728 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3729 total_amount_paid_msat += path.last().unwrap().fee_msat;
3731 assert_eq!(total_amount_paid_msat, 50_000);
3736 fn simple_mpp_route_test() {
3737 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3738 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3739 let scorer = test_utils::TestScorer::with_penalty(0);
3740 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3741 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3742 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3744 // We need a route consisting of 3 paths:
3745 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3746 // To achieve this, the amount being transferred should be around
3747 // the total capacity of these 3 paths.
3749 // First, we set limits on these (previously unlimited) channels.
3750 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3752 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3753 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3754 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3755 short_channel_id: 1,
3758 cltv_expiry_delta: 0,
3759 htlc_minimum_msat: 0,
3760 htlc_maximum_msat: OptionalField::Present(100_000),
3762 fee_proportional_millionths: 0,
3763 excess_data: Vec::new()
3765 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3766 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3767 short_channel_id: 3,
3770 cltv_expiry_delta: 0,
3771 htlc_minimum_msat: 0,
3772 htlc_maximum_msat: OptionalField::Present(50_000),
3774 fee_proportional_millionths: 0,
3775 excess_data: Vec::new()
3778 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3779 // (total limit 60).
3780 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3781 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3782 short_channel_id: 12,
3785 cltv_expiry_delta: 0,
3786 htlc_minimum_msat: 0,
3787 htlc_maximum_msat: OptionalField::Present(60_000),
3789 fee_proportional_millionths: 0,
3790 excess_data: Vec::new()
3792 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3793 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3794 short_channel_id: 13,
3797 cltv_expiry_delta: 0,
3798 htlc_minimum_msat: 0,
3799 htlc_maximum_msat: OptionalField::Present(60_000),
3801 fee_proportional_millionths: 0,
3802 excess_data: Vec::new()
3805 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3806 // (total capacity 180 sats).
3807 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3808 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3809 short_channel_id: 2,
3812 cltv_expiry_delta: 0,
3813 htlc_minimum_msat: 0,
3814 htlc_maximum_msat: OptionalField::Present(200_000),
3816 fee_proportional_millionths: 0,
3817 excess_data: Vec::new()
3819 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3820 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3821 short_channel_id: 4,
3824 cltv_expiry_delta: 0,
3825 htlc_minimum_msat: 0,
3826 htlc_maximum_msat: OptionalField::Present(180_000),
3828 fee_proportional_millionths: 0,
3829 excess_data: Vec::new()
3833 // Attempt to route more than available results in a failure.
3834 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3835 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3836 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3837 } else { panic!(); }
3841 // Now, attempt to route 250 sats (just a bit below the capacity).
3842 // Our algorithm should provide us with these 3 paths.
3843 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3844 assert_eq!(route.paths.len(), 3);
3845 let mut total_amount_paid_msat = 0;
3846 for path in &route.paths {
3847 assert_eq!(path.len(), 2);
3848 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3849 total_amount_paid_msat += path.last().unwrap().fee_msat;
3851 assert_eq!(total_amount_paid_msat, 250_000);
3855 // Attempt to route an exact amount is also fine
3856 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3857 assert_eq!(route.paths.len(), 3);
3858 let mut total_amount_paid_msat = 0;
3859 for path in &route.paths {
3860 assert_eq!(path.len(), 2);
3861 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3862 total_amount_paid_msat += path.last().unwrap().fee_msat;
3864 assert_eq!(total_amount_paid_msat, 290_000);
3869 fn long_mpp_route_test() {
3870 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3871 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3872 let scorer = test_utils::TestScorer::with_penalty(0);
3873 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3874 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3875 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3877 // We need a route consisting of 3 paths:
3878 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3879 // Note that these paths overlap (channels 5, 12, 13).
3880 // We will route 300 sats.
3881 // Each path will have 100 sats capacity, those channels which
3882 // are used twice will have 200 sats capacity.
3884 // Disable other potential paths.
3885 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3886 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3887 short_channel_id: 2,
3890 cltv_expiry_delta: 0,
3891 htlc_minimum_msat: 0,
3892 htlc_maximum_msat: OptionalField::Present(100_000),
3894 fee_proportional_millionths: 0,
3895 excess_data: Vec::new()
3897 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3898 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3899 short_channel_id: 7,
3902 cltv_expiry_delta: 0,
3903 htlc_minimum_msat: 0,
3904 htlc_maximum_msat: OptionalField::Present(100_000),
3906 fee_proportional_millionths: 0,
3907 excess_data: Vec::new()
3910 // Path via {node0, node2} is channels {1, 3, 5}.
3911 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3912 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3913 short_channel_id: 1,
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()
3923 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3924 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3925 short_channel_id: 3,
3928 cltv_expiry_delta: 0,
3929 htlc_minimum_msat: 0,
3930 htlc_maximum_msat: OptionalField::Present(100_000),
3932 fee_proportional_millionths: 0,
3933 excess_data: Vec::new()
3936 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3937 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3938 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3939 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3940 short_channel_id: 5,
3943 cltv_expiry_delta: 0,
3944 htlc_minimum_msat: 0,
3945 htlc_maximum_msat: OptionalField::Present(200_000),
3947 fee_proportional_millionths: 0,
3948 excess_data: Vec::new()
3951 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3952 // Add 100 sats to the capacities of {12, 13}, because these channels
3953 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3954 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3955 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3956 short_channel_id: 12,
3959 cltv_expiry_delta: 0,
3960 htlc_minimum_msat: 0,
3961 htlc_maximum_msat: OptionalField::Present(200_000),
3963 fee_proportional_millionths: 0,
3964 excess_data: Vec::new()
3966 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3967 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3968 short_channel_id: 13,
3971 cltv_expiry_delta: 0,
3972 htlc_minimum_msat: 0,
3973 htlc_maximum_msat: OptionalField::Present(200_000),
3975 fee_proportional_millionths: 0,
3976 excess_data: Vec::new()
3979 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3980 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3981 short_channel_id: 6,
3984 cltv_expiry_delta: 0,
3985 htlc_minimum_msat: 0,
3986 htlc_maximum_msat: OptionalField::Present(100_000),
3988 fee_proportional_millionths: 0,
3989 excess_data: Vec::new()
3991 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3992 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3993 short_channel_id: 11,
3996 cltv_expiry_delta: 0,
3997 htlc_minimum_msat: 0,
3998 htlc_maximum_msat: OptionalField::Present(100_000),
4000 fee_proportional_millionths: 0,
4001 excess_data: Vec::new()
4004 // Path via {node7, node2} is channels {12, 13, 5}.
4005 // We already limited them to 200 sats (they are used twice for 100 sats).
4006 // Nothing to do here.
4009 // Attempt to route more than available results in a failure.
4010 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4011 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4012 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4013 } else { panic!(); }
4017 // Now, attempt to route 300 sats (exact amount we can route).
4018 // Our algorithm should provide us with these 3 paths, 100 sats each.
4019 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4020 assert_eq!(route.paths.len(), 3);
4022 let mut total_amount_paid_msat = 0;
4023 for path in &route.paths {
4024 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4025 total_amount_paid_msat += path.last().unwrap().fee_msat;
4027 assert_eq!(total_amount_paid_msat, 300_000);
4033 fn mpp_cheaper_route_test() {
4034 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4035 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4036 let scorer = test_utils::TestScorer::with_penalty(0);
4037 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4038 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4039 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4041 // This test checks that if we have two cheaper paths and one more expensive path,
4042 // so that liquidity-wise any 2 of 3 combination is sufficient,
4043 // two cheaper paths will be taken.
4044 // These paths have equal available liquidity.
4046 // We need a combination of 3 paths:
4047 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4048 // Note that these paths overlap (channels 5, 12, 13).
4049 // Each path will have 100 sats capacity, those channels which
4050 // are used twice will have 200 sats capacity.
4052 // Disable other potential paths.
4053 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4054 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4055 short_channel_id: 2,
4058 cltv_expiry_delta: 0,
4059 htlc_minimum_msat: 0,
4060 htlc_maximum_msat: OptionalField::Present(100_000),
4062 fee_proportional_millionths: 0,
4063 excess_data: Vec::new()
4065 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4066 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4067 short_channel_id: 7,
4070 cltv_expiry_delta: 0,
4071 htlc_minimum_msat: 0,
4072 htlc_maximum_msat: OptionalField::Present(100_000),
4074 fee_proportional_millionths: 0,
4075 excess_data: Vec::new()
4078 // Path via {node0, node2} is channels {1, 3, 5}.
4079 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4080 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4081 short_channel_id: 1,
4084 cltv_expiry_delta: 0,
4085 htlc_minimum_msat: 0,
4086 htlc_maximum_msat: OptionalField::Present(100_000),
4088 fee_proportional_millionths: 0,
4089 excess_data: Vec::new()
4091 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4092 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4093 short_channel_id: 3,
4096 cltv_expiry_delta: 0,
4097 htlc_minimum_msat: 0,
4098 htlc_maximum_msat: OptionalField::Present(100_000),
4100 fee_proportional_millionths: 0,
4101 excess_data: Vec::new()
4104 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4105 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4106 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4107 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4108 short_channel_id: 5,
4111 cltv_expiry_delta: 0,
4112 htlc_minimum_msat: 0,
4113 htlc_maximum_msat: OptionalField::Present(200_000),
4115 fee_proportional_millionths: 0,
4116 excess_data: Vec::new()
4119 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4120 // Add 100 sats to the capacities of {12, 13}, because these channels
4121 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4122 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4123 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4124 short_channel_id: 12,
4127 cltv_expiry_delta: 0,
4128 htlc_minimum_msat: 0,
4129 htlc_maximum_msat: OptionalField::Present(200_000),
4131 fee_proportional_millionths: 0,
4132 excess_data: Vec::new()
4134 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4135 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4136 short_channel_id: 13,
4139 cltv_expiry_delta: 0,
4140 htlc_minimum_msat: 0,
4141 htlc_maximum_msat: OptionalField::Present(200_000),
4143 fee_proportional_millionths: 0,
4144 excess_data: Vec::new()
4147 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4148 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4149 short_channel_id: 6,
4152 cltv_expiry_delta: 0,
4153 htlc_minimum_msat: 0,
4154 htlc_maximum_msat: OptionalField::Present(100_000),
4155 fee_base_msat: 1_000,
4156 fee_proportional_millionths: 0,
4157 excess_data: Vec::new()
4159 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4160 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4161 short_channel_id: 11,
4164 cltv_expiry_delta: 0,
4165 htlc_minimum_msat: 0,
4166 htlc_maximum_msat: OptionalField::Present(100_000),
4168 fee_proportional_millionths: 0,
4169 excess_data: Vec::new()
4172 // Path via {node7, node2} is channels {12, 13, 5}.
4173 // We already limited them to 200 sats (they are used twice for 100 sats).
4174 // Nothing to do here.
4177 // Now, attempt to route 180 sats.
4178 // Our algorithm should provide us with these 2 paths.
4179 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4180 assert_eq!(route.paths.len(), 2);
4182 let mut total_value_transferred_msat = 0;
4183 let mut total_paid_msat = 0;
4184 for path in &route.paths {
4185 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4186 total_value_transferred_msat += path.last().unwrap().fee_msat;
4188 total_paid_msat += hop.fee_msat;
4191 // If we paid fee, this would be higher.
4192 assert_eq!(total_value_transferred_msat, 180_000);
4193 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4194 assert_eq!(total_fees_paid, 0);
4199 fn fees_on_mpp_route_test() {
4200 // This test makes sure that MPP algorithm properly takes into account
4201 // fees charged on the channels, by making the fees impactful:
4202 // if the fee is not properly accounted for, the behavior is different.
4203 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4204 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4205 let scorer = test_utils::TestScorer::with_penalty(0);
4206 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4207 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4208 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4210 // We need a route consisting of 2 paths:
4211 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4212 // We will route 200 sats, Each path will have 100 sats capacity.
4214 // This test is not particularly stable: e.g.,
4215 // there's a way to route via {node0, node2, node4}.
4216 // It works while pathfinding is deterministic, but can be broken otherwise.
4217 // It's fine to ignore this concern for now.
4219 // Disable other potential paths.
4220 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4221 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4222 short_channel_id: 2,
4225 cltv_expiry_delta: 0,
4226 htlc_minimum_msat: 0,
4227 htlc_maximum_msat: OptionalField::Present(100_000),
4229 fee_proportional_millionths: 0,
4230 excess_data: Vec::new()
4233 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4234 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4235 short_channel_id: 7,
4238 cltv_expiry_delta: 0,
4239 htlc_minimum_msat: 0,
4240 htlc_maximum_msat: OptionalField::Present(100_000),
4242 fee_proportional_millionths: 0,
4243 excess_data: Vec::new()
4246 // Path via {node0, node2} is channels {1, 3, 5}.
4247 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4248 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4249 short_channel_id: 1,
4252 cltv_expiry_delta: 0,
4253 htlc_minimum_msat: 0,
4254 htlc_maximum_msat: OptionalField::Present(100_000),
4256 fee_proportional_millionths: 0,
4257 excess_data: Vec::new()
4259 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4260 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4261 short_channel_id: 3,
4264 cltv_expiry_delta: 0,
4265 htlc_minimum_msat: 0,
4266 htlc_maximum_msat: OptionalField::Present(100_000),
4268 fee_proportional_millionths: 0,
4269 excess_data: Vec::new()
4272 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4273 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4274 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4275 short_channel_id: 5,
4278 cltv_expiry_delta: 0,
4279 htlc_minimum_msat: 0,
4280 htlc_maximum_msat: OptionalField::Present(100_000),
4282 fee_proportional_millionths: 0,
4283 excess_data: Vec::new()
4286 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4287 // All channels should be 100 sats capacity. But for the fee experiment,
4288 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4289 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4290 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4291 // so no matter how large are other channels,
4292 // the whole path will be limited by 100 sats with just these 2 conditions:
4293 // - channel 12 capacity is 250 sats
4294 // - fee for channel 6 is 150 sats
4295 // Let's test this by enforcing these 2 conditions and removing other limits.
4296 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4297 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4298 short_channel_id: 12,
4301 cltv_expiry_delta: 0,
4302 htlc_minimum_msat: 0,
4303 htlc_maximum_msat: OptionalField::Present(250_000),
4305 fee_proportional_millionths: 0,
4306 excess_data: Vec::new()
4308 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4309 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4310 short_channel_id: 13,
4313 cltv_expiry_delta: 0,
4314 htlc_minimum_msat: 0,
4315 htlc_maximum_msat: OptionalField::Absent,
4317 fee_proportional_millionths: 0,
4318 excess_data: Vec::new()
4321 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4322 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4323 short_channel_id: 6,
4326 cltv_expiry_delta: 0,
4327 htlc_minimum_msat: 0,
4328 htlc_maximum_msat: OptionalField::Absent,
4329 fee_base_msat: 150_000,
4330 fee_proportional_millionths: 0,
4331 excess_data: Vec::new()
4333 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4334 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4335 short_channel_id: 11,
4338 cltv_expiry_delta: 0,
4339 htlc_minimum_msat: 0,
4340 htlc_maximum_msat: OptionalField::Absent,
4342 fee_proportional_millionths: 0,
4343 excess_data: Vec::new()
4347 // Attempt to route more than available results in a failure.
4348 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4349 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4350 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4351 } else { panic!(); }
4355 // Now, attempt to route 200 sats (exact amount we can route).
4356 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4357 assert_eq!(route.paths.len(), 2);
4359 let mut total_amount_paid_msat = 0;
4360 for path in &route.paths {
4361 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4362 total_amount_paid_msat += path.last().unwrap().fee_msat;
4364 assert_eq!(total_amount_paid_msat, 200_000);
4365 assert_eq!(route.get_total_fees(), 150_000);
4370 fn mpp_with_last_hops() {
4371 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4372 // via a single last-hop route hint, we'd fail to route if we first collected routes
4373 // totaling close but not quite enough to fund the full payment.
4375 // This was because we considered last-hop hints to have exactly the sought payment amount
4376 // instead of the amount we were trying to collect, needlessly limiting our path searching
4377 // at the very first hop.
4379 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4380 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4381 // to only have the remaining to-collect amount in available liquidity.
4383 // This bug appeared in production in some specific channel configurations.
4384 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4385 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4386 let scorer = test_utils::TestScorer::with_penalty(0);
4387 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4388 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4389 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4390 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4391 src_node_id: nodes[2],
4392 short_channel_id: 42,
4393 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4394 cltv_expiry_delta: 42,
4395 htlc_minimum_msat: None,
4396 htlc_maximum_msat: None,
4399 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4400 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4401 // would first use the no-fee route and then fail to find a path along the second route as
4402 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4403 // under 5% of our payment amount.
4404 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4405 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4406 short_channel_id: 1,
4409 cltv_expiry_delta: (5 << 4) | 5,
4410 htlc_minimum_msat: 0,
4411 htlc_maximum_msat: OptionalField::Present(99_000),
4412 fee_base_msat: u32::max_value(),
4413 fee_proportional_millionths: u32::max_value(),
4414 excess_data: Vec::new()
4416 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4417 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4418 short_channel_id: 2,
4421 cltv_expiry_delta: (5 << 4) | 3,
4422 htlc_minimum_msat: 0,
4423 htlc_maximum_msat: OptionalField::Present(99_000),
4424 fee_base_msat: u32::max_value(),
4425 fee_proportional_millionths: u32::max_value(),
4426 excess_data: Vec::new()
4428 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4429 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4430 short_channel_id: 4,
4433 cltv_expiry_delta: (4 << 4) | 1,
4434 htlc_minimum_msat: 0,
4435 htlc_maximum_msat: OptionalField::Absent,
4437 fee_proportional_millionths: 0,
4438 excess_data: Vec::new()
4440 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4441 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4442 short_channel_id: 13,
4444 flags: 0|2, // Channel disabled
4445 cltv_expiry_delta: (13 << 4) | 1,
4446 htlc_minimum_msat: 0,
4447 htlc_maximum_msat: OptionalField::Absent,
4449 fee_proportional_millionths: 2000000,
4450 excess_data: Vec::new()
4453 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4455 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4456 assert_eq!(route.paths.len(), 2);
4457 // Paths are somewhat randomly ordered, but:
4458 // * the first is channel 2 (1 msat fee) -> channel 4 -> channel 42
4459 // * the second is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4460 assert_eq!(route.paths[0][0].short_channel_id, 2);
4461 assert_eq!(route.paths[0][0].fee_msat, 1);
4462 assert_eq!(route.paths[0][2].fee_msat, 1_000);
4463 assert_eq!(route.paths[1][0].short_channel_id, 1);
4464 assert_eq!(route.paths[1][0].fee_msat, 0);
4465 assert_eq!(route.paths[1][2].fee_msat, 99_000);
4466 assert_eq!(route.get_total_fees(), 1);
4467 assert_eq!(route.get_total_amount(), 100_000);
4471 fn drop_lowest_channel_mpp_route_test() {
4472 // This test checks that low-capacity channel is dropped when after
4473 // path finding we realize that we found more capacity than we need.
4474 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4475 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4476 let scorer = test_utils::TestScorer::with_penalty(0);
4477 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4478 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4479 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4481 // We need a route consisting of 3 paths:
4482 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4484 // The first and the second paths should be sufficient, but the third should be
4485 // cheaper, so that we select it but drop later.
4487 // First, we set limits on these (previously unlimited) channels.
4488 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4490 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4491 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4492 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4493 short_channel_id: 1,
4496 cltv_expiry_delta: 0,
4497 htlc_minimum_msat: 0,
4498 htlc_maximum_msat: OptionalField::Present(100_000),
4500 fee_proportional_millionths: 0,
4501 excess_data: Vec::new()
4503 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4504 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4505 short_channel_id: 3,
4508 cltv_expiry_delta: 0,
4509 htlc_minimum_msat: 0,
4510 htlc_maximum_msat: OptionalField::Present(50_000),
4512 fee_proportional_millionths: 0,
4513 excess_data: Vec::new()
4516 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4517 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4518 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4519 short_channel_id: 12,
4522 cltv_expiry_delta: 0,
4523 htlc_minimum_msat: 0,
4524 htlc_maximum_msat: OptionalField::Present(60_000),
4526 fee_proportional_millionths: 0,
4527 excess_data: Vec::new()
4529 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4530 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4531 short_channel_id: 13,
4534 cltv_expiry_delta: 0,
4535 htlc_minimum_msat: 0,
4536 htlc_maximum_msat: OptionalField::Present(60_000),
4538 fee_proportional_millionths: 0,
4539 excess_data: Vec::new()
4542 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4543 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4544 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4545 short_channel_id: 2,
4548 cltv_expiry_delta: 0,
4549 htlc_minimum_msat: 0,
4550 htlc_maximum_msat: OptionalField::Present(20_000),
4552 fee_proportional_millionths: 0,
4553 excess_data: Vec::new()
4555 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4556 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4557 short_channel_id: 4,
4560 cltv_expiry_delta: 0,
4561 htlc_minimum_msat: 0,
4562 htlc_maximum_msat: OptionalField::Present(20_000),
4564 fee_proportional_millionths: 0,
4565 excess_data: Vec::new()
4569 // Attempt to route more than available results in a failure.
4570 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4571 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4572 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4573 } else { panic!(); }
4577 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4578 // Our algorithm should provide us with these 3 paths.
4579 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4580 assert_eq!(route.paths.len(), 3);
4581 let mut total_amount_paid_msat = 0;
4582 for path in &route.paths {
4583 assert_eq!(path.len(), 2);
4584 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4585 total_amount_paid_msat += path.last().unwrap().fee_msat;
4587 assert_eq!(total_amount_paid_msat, 125_000);
4591 // Attempt to route without the last small cheap channel
4592 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4593 assert_eq!(route.paths.len(), 2);
4594 let mut total_amount_paid_msat = 0;
4595 for path in &route.paths {
4596 assert_eq!(path.len(), 2);
4597 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4598 total_amount_paid_msat += path.last().unwrap().fee_msat;
4600 assert_eq!(total_amount_paid_msat, 90_000);
4605 fn min_criteria_consistency() {
4606 // Test that we don't use an inconsistent metric between updating and walking nodes during
4607 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4608 // was updated with a different criterion from the heap sorting, resulting in loops in
4609 // calculated paths. We test for that specific case here.
4611 // We construct a network that looks like this:
4613 // node2 -1(3)2- node3
4617 // node1 -1(5)2- node4 -1(1)2- node6
4623 // We create a loop on the side of our real path - our destination is node 6, with a
4624 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4625 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4626 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4627 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4628 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4629 // "previous hop" being set to node 3, creating a loop in the path.
4630 let secp_ctx = Secp256k1::new();
4631 let logger = Arc::new(test_utils::TestLogger::new());
4632 let network = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
4633 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network), None, Arc::clone(&logger));
4634 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4635 let scorer = test_utils::TestScorer::with_penalty(0);
4636 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4637 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4638 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4640 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4641 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4642 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4643 short_channel_id: 6,
4646 cltv_expiry_delta: (6 << 4) | 0,
4647 htlc_minimum_msat: 0,
4648 htlc_maximum_msat: OptionalField::Absent,
4650 fee_proportional_millionths: 0,
4651 excess_data: Vec::new()
4653 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4655 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4656 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4657 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4658 short_channel_id: 5,
4661 cltv_expiry_delta: (5 << 4) | 0,
4662 htlc_minimum_msat: 0,
4663 htlc_maximum_msat: OptionalField::Absent,
4665 fee_proportional_millionths: 0,
4666 excess_data: Vec::new()
4668 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4670 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4671 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4672 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4673 short_channel_id: 4,
4676 cltv_expiry_delta: (4 << 4) | 0,
4677 htlc_minimum_msat: 0,
4678 htlc_maximum_msat: OptionalField::Absent,
4680 fee_proportional_millionths: 0,
4681 excess_data: Vec::new()
4683 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4685 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4686 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4687 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4688 short_channel_id: 3,
4691 cltv_expiry_delta: (3 << 4) | 0,
4692 htlc_minimum_msat: 0,
4693 htlc_maximum_msat: OptionalField::Absent,
4695 fee_proportional_millionths: 0,
4696 excess_data: Vec::new()
4698 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4700 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4701 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4702 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4703 short_channel_id: 2,
4706 cltv_expiry_delta: (2 << 4) | 0,
4707 htlc_minimum_msat: 0,
4708 htlc_maximum_msat: OptionalField::Absent,
4710 fee_proportional_millionths: 0,
4711 excess_data: Vec::new()
4714 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4715 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4716 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4717 short_channel_id: 1,
4720 cltv_expiry_delta: (1 << 4) | 0,
4721 htlc_minimum_msat: 100,
4722 htlc_maximum_msat: OptionalField::Absent,
4724 fee_proportional_millionths: 0,
4725 excess_data: Vec::new()
4727 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4730 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4731 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4732 assert_eq!(route.paths.len(), 1);
4733 assert_eq!(route.paths[0].len(), 3);
4735 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4736 assert_eq!(route.paths[0][0].short_channel_id, 6);
4737 assert_eq!(route.paths[0][0].fee_msat, 100);
4738 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4739 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4740 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4742 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4743 assert_eq!(route.paths[0][1].short_channel_id, 5);
4744 assert_eq!(route.paths[0][1].fee_msat, 0);
4745 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4746 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4747 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4749 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4750 assert_eq!(route.paths[0][2].short_channel_id, 1);
4751 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4752 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4753 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4754 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4760 fn exact_fee_liquidity_limit() {
4761 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4762 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4763 // we calculated fees on a higher value, resulting in us ignoring such paths.
4764 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4765 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4766 let scorer = test_utils::TestScorer::with_penalty(0);
4767 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4768 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4769 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4771 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4773 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4774 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4775 short_channel_id: 2,
4778 cltv_expiry_delta: 0,
4779 htlc_minimum_msat: 0,
4780 htlc_maximum_msat: OptionalField::Present(85_000),
4782 fee_proportional_millionths: 0,
4783 excess_data: Vec::new()
4786 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4787 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4788 short_channel_id: 12,
4791 cltv_expiry_delta: (4 << 4) | 1,
4792 htlc_minimum_msat: 0,
4793 htlc_maximum_msat: OptionalField::Present(270_000),
4795 fee_proportional_millionths: 1000000,
4796 excess_data: Vec::new()
4800 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4801 // 200% fee charged channel 13 in the 1-to-2 direction.
4802 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4803 assert_eq!(route.paths.len(), 1);
4804 assert_eq!(route.paths[0].len(), 2);
4806 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4807 assert_eq!(route.paths[0][0].short_channel_id, 12);
4808 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4809 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4810 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4811 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4813 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4814 assert_eq!(route.paths[0][1].short_channel_id, 13);
4815 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4816 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4817 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4818 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4823 fn htlc_max_reduction_below_min() {
4824 // Test that if, while walking the graph, we reduce the value being sent to meet an
4825 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4826 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4827 // resulting in us thinking there is no possible path, even if other paths exist.
4828 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4829 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4830 let scorer = test_utils::TestScorer::with_penalty(0);
4831 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4832 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4833 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4835 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4836 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4837 // then try to send 90_000.
4838 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4839 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4840 short_channel_id: 2,
4843 cltv_expiry_delta: 0,
4844 htlc_minimum_msat: 0,
4845 htlc_maximum_msat: OptionalField::Present(80_000),
4847 fee_proportional_millionths: 0,
4848 excess_data: Vec::new()
4850 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4851 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4852 short_channel_id: 4,
4855 cltv_expiry_delta: (4 << 4) | 1,
4856 htlc_minimum_msat: 90_000,
4857 htlc_maximum_msat: OptionalField::Absent,
4859 fee_proportional_millionths: 0,
4860 excess_data: Vec::new()
4864 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4865 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4866 // expensive) channels 12-13 path.
4867 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4868 assert_eq!(route.paths.len(), 1);
4869 assert_eq!(route.paths[0].len(), 2);
4871 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4872 assert_eq!(route.paths[0][0].short_channel_id, 12);
4873 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4874 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4875 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4876 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4878 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4879 assert_eq!(route.paths[0][1].short_channel_id, 13);
4880 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4881 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4882 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
4883 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4888 fn multiple_direct_first_hops() {
4889 // Previously we'd only ever considered one first hop path per counterparty.
4890 // However, as we don't restrict users to one channel per peer, we really need to support
4891 // looking at all first hop paths.
4892 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4893 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4894 // route over multiple channels with the same first hop.
4895 let secp_ctx = Secp256k1::new();
4896 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4897 let logger = Arc::new(test_utils::TestLogger::new());
4898 let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
4899 let scorer = test_utils::TestScorer::with_penalty(0);
4900 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
4901 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4902 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4905 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4906 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
4907 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
4908 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4909 assert_eq!(route.paths.len(), 1);
4910 assert_eq!(route.paths[0].len(), 1);
4912 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4913 assert_eq!(route.paths[0][0].short_channel_id, 3);
4914 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4917 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4918 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4919 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4920 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4921 assert_eq!(route.paths.len(), 2);
4922 assert_eq!(route.paths[0].len(), 1);
4923 assert_eq!(route.paths[1].len(), 1);
4925 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4926 assert_eq!(route.paths[0][0].short_channel_id, 3);
4927 assert_eq!(route.paths[0][0].fee_msat, 50_000);
4929 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
4930 assert_eq!(route.paths[1][0].short_channel_id, 2);
4931 assert_eq!(route.paths[1][0].fee_msat, 50_000);
4935 // If we have a bunch of outbound channels to the same node, where most are not
4936 // sufficient to pay the full payment, but one is, we should default to just using the
4937 // one single channel that has sufficient balance, avoiding MPP.
4939 // If we have several options above the 3xpayment value threshold, we should pick the
4940 // smallest of them, avoiding further fragmenting our available outbound balance to
4942 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4943 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4944 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4945 &get_channel_details(Some(5), nodes[0], InitFeatures::known(), 50_000),
4946 &get_channel_details(Some(6), nodes[0], InitFeatures::known(), 300_000),
4947 &get_channel_details(Some(7), nodes[0], InitFeatures::known(), 50_000),
4948 &get_channel_details(Some(8), nodes[0], InitFeatures::known(), 50_000),
4949 &get_channel_details(Some(9), nodes[0], InitFeatures::known(), 50_000),
4950 &get_channel_details(Some(4), nodes[0], InitFeatures::known(), 1_000_000),
4951 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4952 assert_eq!(route.paths.len(), 1);
4953 assert_eq!(route.paths[0].len(), 1);
4955 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4956 assert_eq!(route.paths[0][0].short_channel_id, 6);
4957 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4962 fn prefers_shorter_route_with_higher_fees() {
4963 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4964 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4965 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4967 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
4968 let scorer = test_utils::TestScorer::with_penalty(0);
4969 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4970 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4971 let route = get_route(
4972 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
4973 Arc::clone(&logger), &scorer, &random_seed_bytes
4975 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4977 assert_eq!(route.get_total_fees(), 100);
4978 assert_eq!(route.get_total_amount(), 100);
4979 assert_eq!(path, vec![2, 4, 6, 11, 8]);
4981 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
4982 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
4983 let scorer = test_utils::TestScorer::with_penalty(100);
4984 let route = get_route(
4985 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
4986 Arc::clone(&logger), &scorer, &random_seed_bytes
4988 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
4990 assert_eq!(route.get_total_fees(), 300);
4991 assert_eq!(route.get_total_amount(), 100);
4992 assert_eq!(path, vec![2, 4, 7, 10]);
4995 struct BadChannelScorer {
4996 short_channel_id: u64,
5000 impl Writeable for BadChannelScorer {
5001 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5003 impl Score for BadChannelScorer {
5004 fn channel_penalty_msat(&self, short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId) -> u64 {
5005 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5008 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5009 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5012 struct BadNodeScorer {
5017 impl Writeable for BadNodeScorer {
5018 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5021 impl Score for BadNodeScorer {
5022 fn channel_penalty_msat(&self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, target: &NodeId) -> u64 {
5023 if *target == self.node_id { u64::max_value() } else { 0 }
5026 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5027 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5031 fn avoids_routing_through_bad_channels_and_nodes() {
5032 let (secp_ctx, network, _, _, logger) = build_graph();
5033 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5034 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5035 let network_graph = network.read_only();
5037 // A path to nodes[6] exists when no penalties are applied to any channel.
5038 let scorer = test_utils::TestScorer::with_penalty(0);
5039 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5040 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5041 let route = get_route(
5042 &our_id, &payment_params, &network_graph, None, 100, 42,
5043 Arc::clone(&logger), &scorer, &random_seed_bytes
5045 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5047 assert_eq!(route.get_total_fees(), 100);
5048 assert_eq!(route.get_total_amount(), 100);
5049 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5051 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5052 let scorer = BadChannelScorer { short_channel_id: 6 };
5053 let route = get_route(
5054 &our_id, &payment_params, &network_graph, None, 100, 42,
5055 Arc::clone(&logger), &scorer, &random_seed_bytes
5057 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5059 assert_eq!(route.get_total_fees(), 300);
5060 assert_eq!(route.get_total_amount(), 100);
5061 assert_eq!(path, vec![2, 4, 7, 10]);
5063 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5064 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5066 &our_id, &payment_params, &network_graph, None, 100, 42,
5067 Arc::clone(&logger), &scorer, &random_seed_bytes
5069 Err(LightningError { err, .. } ) => {
5070 assert_eq!(err, "Failed to find a path to the given destination");
5072 Ok(_) => panic!("Expected error"),
5077 fn total_fees_single_path() {
5081 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5082 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5083 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5086 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5087 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5088 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5091 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5092 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5093 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5096 payment_params: None,
5099 assert_eq!(route.get_total_fees(), 250);
5100 assert_eq!(route.get_total_amount(), 225);
5104 fn total_fees_multi_path() {
5108 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5109 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5110 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5113 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5114 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5115 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5119 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5120 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5121 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5124 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5125 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5126 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5129 payment_params: None,
5132 assert_eq!(route.get_total_fees(), 200);
5133 assert_eq!(route.get_total_amount(), 300);
5137 fn total_empty_route_no_panic() {
5138 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5139 // would both panic if the route was completely empty. We test to ensure they return 0
5140 // here, even though its somewhat nonsensical as a route.
5141 let route = Route { paths: Vec::new(), payment_params: None };
5143 assert_eq!(route.get_total_fees(), 0);
5144 assert_eq!(route.get_total_amount(), 0);
5148 fn limits_total_cltv_delta() {
5149 let (secp_ctx, network, _, _, logger) = build_graph();
5150 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5151 let network_graph = network.read_only();
5153 let scorer = test_utils::TestScorer::with_penalty(0);
5155 // Make sure that generally there is at least one route available
5156 let feasible_max_total_cltv_delta = 1008;
5157 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5158 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5159 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5160 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5161 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5162 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5163 assert_ne!(path.len(), 0);
5165 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5166 let fail_max_total_cltv_delta = 23;
5167 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5168 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5169 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5171 Err(LightningError { err, .. } ) => {
5172 assert_eq!(err, "Failed to find a path to the given destination");
5174 Ok(_) => panic!("Expected error"),
5179 fn adds_and_limits_cltv_offset() {
5180 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5181 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5183 let scorer = test_utils::TestScorer::with_penalty(0);
5185 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5186 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5187 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5188 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5189 assert_eq!(route.paths.len(), 1);
5191 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5193 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5194 let mut route_default = route.clone();
5195 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5196 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5197 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5198 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5199 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5201 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5202 let mut route_limited = route.clone();
5203 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5204 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5205 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5206 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5207 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5211 fn adds_plausible_cltv_offset() {
5212 let (secp_ctx, network, _, _, logger) = build_graph();
5213 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5214 let network_graph = network.read_only();
5215 let network_nodes = network_graph.nodes();
5216 let network_channels = network_graph.channels();
5217 let scorer = test_utils::TestScorer::with_penalty(0);
5218 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5219 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5220 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5222 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5223 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5224 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5226 let mut path_plausibility = vec![];
5228 for p in route.paths {
5229 // 1. Select random observation point
5230 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5231 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5233 prng.process_in_place(&mut random_bytes);
5234 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5235 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5237 // 2. Calculate what CLTV expiry delta we would observe there
5238 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5240 // 3. Starting from the observation point, find candidate paths
5241 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5242 candidates.push_back((observation_point, vec![]));
5244 let mut found_plausible_candidate = false;
5246 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5247 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5248 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5249 found_plausible_candidate = true;
5250 break 'candidate_loop;
5254 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5255 for channel_id in &cur_node.channels {
5256 if let Some(channel_info) = network_channels.get(&channel_id) {
5257 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5258 if let Some(channel_update_info) = dir_info.direction() {
5259 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5260 if cur_path_cltv_deltas.iter().sum::<u32>()
5261 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5262 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5263 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5264 candidates.push_back((*next_id, new_path_cltv_deltas));
5273 path_plausibility.push(found_plausible_candidate);
5275 assert!(path_plausibility.iter().all(|x| *x));
5278 #[cfg(not(feature = "no-std"))]
5279 pub(super) fn random_init_seed() -> u64 {
5280 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5281 use core::hash::{BuildHasher, Hasher};
5282 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5283 println!("Using seed of {}", seed);
5286 #[cfg(not(feature = "no-std"))]
5287 use util::ser::Readable;
5290 #[cfg(not(feature = "no-std"))]
5291 fn generate_routes() {
5292 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5294 let mut d = match super::test_utils::get_route_file() {
5301 let graph = NetworkGraph::read(&mut d).unwrap();
5302 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5303 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5305 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5306 let mut seed = random_init_seed() as usize;
5307 let nodes = graph.read_only().nodes().clone();
5308 'load_endpoints: for _ in 0..10 {
5310 seed = seed.overflowing_mul(0xdeadbeef).0;
5311 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5312 seed = seed.overflowing_mul(0xdeadbeef).0;
5313 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5314 let payment_params = PaymentParameters::from_node_id(dst);
5315 let amt = seed as u64 % 200_000_000;
5316 let params = ProbabilisticScoringParameters::default();
5317 let scorer = ProbabilisticScorer::new(params, &graph);
5318 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5319 continue 'load_endpoints;
5326 #[cfg(not(feature = "no-std"))]
5327 fn generate_routes_mpp() {
5328 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5330 let mut d = match super::test_utils::get_route_file() {
5337 let graph = NetworkGraph::read(&mut d).unwrap();
5338 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5339 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5341 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5342 let mut seed = random_init_seed() as usize;
5343 let nodes = graph.read_only().nodes().clone();
5344 'load_endpoints: for _ in 0..10 {
5346 seed = seed.overflowing_mul(0xdeadbeef).0;
5347 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5348 seed = seed.overflowing_mul(0xdeadbeef).0;
5349 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5350 let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
5351 let amt = seed as u64 % 200_000_000;
5352 let params = ProbabilisticScoringParameters::default();
5353 let scorer = ProbabilisticScorer::new(params, &graph);
5354 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5355 continue 'load_endpoints;
5362 #[cfg(all(test, not(feature = "no-std")))]
5363 pub(crate) mod test_utils {
5365 /// Tries to open a network graph file, or panics with a URL to fetch it.
5366 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5367 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5368 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5369 .or_else(|_| { // Fall back to guessing based on the binary location
5370 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5371 let mut path = std::env::current_exe().unwrap();
5372 path.pop(); // lightning-...
5374 path.pop(); // debug
5375 path.pop(); // target
5376 path.push("lightning");
5377 path.push("net_graph-2021-05-31.bin");
5378 eprintln!("{}", path.to_str().unwrap());
5381 .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");
5382 #[cfg(require_route_graph_test)]
5383 return Ok(res.unwrap());
5384 #[cfg(not(require_route_graph_test))]
5389 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5392 use bitcoin::hashes::Hash;
5393 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5394 use chain::transaction::OutPoint;
5395 use chain::keysinterface::{KeysManager,KeysInterface};
5396 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
5397 use ln::features::{InitFeatures, InvoiceFeatures};
5398 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters, Scorer};
5399 use util::logger::{Logger, Record};
5403 struct DummyLogger {}
5404 impl Logger for DummyLogger {
5405 fn log(&self, _record: &Record) {}
5408 fn read_network_graph() -> NetworkGraph {
5409 let mut d = test_utils::get_route_file().unwrap();
5410 NetworkGraph::read(&mut d).unwrap()
5413 fn payer_pubkey() -> PublicKey {
5414 let secp_ctx = Secp256k1::new();
5415 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5419 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5421 channel_id: [0; 32],
5422 counterparty: ChannelCounterparty {
5423 features: InitFeatures::known(),
5425 unspendable_punishment_reserve: 0,
5426 forwarding_info: None,
5428 funding_txo: Some(OutPoint {
5429 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5431 short_channel_id: Some(1),
5432 inbound_scid_alias: None,
5433 channel_value_satoshis: 10_000_000,
5435 balance_msat: 10_000_000,
5436 outbound_capacity_msat: 10_000_000,
5437 inbound_capacity_msat: 0,
5438 unspendable_punishment_reserve: None,
5439 confirmations_required: None,
5440 force_close_spend_delay: None,
5442 is_funding_locked: true,
5449 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5450 let network_graph = read_network_graph();
5451 let scorer = FixedPenaltyScorer::with_penalty(0);
5452 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5456 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5457 let network_graph = read_network_graph();
5458 let scorer = FixedPenaltyScorer::with_penalty(0);
5459 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5463 fn generate_routes_with_default_scorer(bench: &mut Bencher) {
5464 let network_graph = read_network_graph();
5465 let scorer = Scorer::default();
5466 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5470 fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
5471 let network_graph = read_network_graph();
5472 let scorer = Scorer::default();
5473 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5477 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5478 let network_graph = read_network_graph();
5479 let params = ProbabilisticScoringParameters::default();
5480 let scorer = ProbabilisticScorer::new(params, &network_graph);
5481 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5485 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5486 let network_graph = read_network_graph();
5487 let params = ProbabilisticScoringParameters::default();
5488 let scorer = ProbabilisticScorer::new(params, &network_graph);
5489 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5492 fn generate_routes<S: Score>(
5493 bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
5495 let nodes = graph.read_only().nodes().clone();
5496 let payer = payer_pubkey();
5497 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5498 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5500 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5501 let mut routes = Vec::new();
5502 let mut route_endpoints = Vec::new();
5503 let mut seed: usize = 0xdeadbeef;
5504 'load_endpoints: for _ in 0..150 {
5507 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5509 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5510 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5511 let first_hop = first_hop(src);
5512 let amt = seed as u64 % 1_000_000;
5513 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5515 route_endpoints.push((first_hop, params, amt));
5516 continue 'load_endpoints;
5521 // ...and seed the scorer with success and failure data...
5522 for route in routes {
5523 let amount = route.get_total_amount();
5524 if amount < 250_000 {
5525 for path in route.paths {
5526 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5528 } else if amount > 750_000 {
5529 for path in route.paths {
5530 let short_channel_id = path[path.len() / 2].short_channel_id;
5531 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5536 // Because we've changed channel scores, its possible we'll take different routes to the
5537 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5538 // requires a too-high CLTV delta.
5539 route_endpoints.retain(|(first_hop, params, amt)| {
5540 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5542 route_endpoints.truncate(100);
5543 assert_eq!(route_endpoints.len(), 100);
5545 // ...then benchmark finding paths between the nodes we learned.
5548 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5549 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());