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::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. Each entry represents a list of hops, NOT
69 /// INCLUDING our own, where the last hop is the destination. Thus, this must always be at
70 /// least length one. While the maximum length of any given path is variable, keeping the length
71 /// of any path less or equal to 19 should currently ensure it is viable.
72 pub paths: Vec<Vec<RouteHop>>,
73 /// The `payment_params` parameter passed to [`find_route`].
74 /// This is used by `ChannelManager` to track information which may be required for retries,
75 /// provided back to you via [`Event::PaymentPathFailed`].
77 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
78 pub payment_params: Option<PaymentParameters>,
81 pub(crate) trait RoutePath {
82 /// Gets the fees for a given path, excluding any excess paid to the recipient.
83 fn get_path_fees(&self) -> u64;
85 impl RoutePath for Vec<RouteHop> {
86 fn get_path_fees(&self) -> u64 {
87 // Do not count last hop of each path since that's the full value of the payment
88 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
89 .iter().map(|hop| &hop.fee_msat)
95 /// Returns the total amount of fees paid on this [`Route`].
97 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
98 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
99 pub fn get_total_fees(&self) -> u64 {
100 self.paths.iter().map(|path| path.get_path_fees()).sum()
103 /// Returns the total amount paid on this [`Route`], excluding the fees.
104 pub fn get_total_amount(&self) -> u64 {
105 return self.paths.iter()
106 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
111 const SERIALIZATION_VERSION: u8 = 1;
112 const MIN_SERIALIZATION_VERSION: u8 = 1;
114 impl Writeable for Route {
115 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
116 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
117 (self.paths.len() as u64).write(writer)?;
118 for hops in self.paths.iter() {
119 (hops.len() as u8).write(writer)?;
120 for hop in hops.iter() {
124 write_tlv_fields!(writer, {
125 (1, self.payment_params, option),
131 impl Readable for Route {
132 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
133 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
134 let path_count: u64 = Readable::read(reader)?;
135 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
136 for _ in 0..path_count {
137 let hop_count: u8 = Readable::read(reader)?;
138 let mut hops = Vec::with_capacity(hop_count as usize);
139 for _ in 0..hop_count {
140 hops.push(Readable::read(reader)?);
144 let mut payment_params = None;
145 read_tlv_fields!(reader, {
146 (1, payment_params, option),
148 Ok(Route { paths, payment_params })
152 /// Parameters needed to find a [`Route`].
154 /// Passed to [`find_route`] and also provided in [`Event::PaymentPathFailed`] for retrying a failed
157 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
158 #[derive(Clone, Debug)]
159 pub struct RouteParameters {
160 /// The parameters of the failed payment path.
161 pub payment_params: PaymentParameters,
163 /// The amount in msats sent on the failed payment path.
164 pub final_value_msat: u64,
166 /// The CLTV on the final hop of the failed payment path.
167 pub final_cltv_expiry_delta: u32,
170 impl_writeable_tlv_based!(RouteParameters, {
171 (0, payment_params, required),
172 (2, final_value_msat, required),
173 (4, final_cltv_expiry_delta, required),
176 /// Maximum total CTLV difference we allow for a full payment path.
177 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
179 // The median hop CLTV expiry delta currently seen in the network.
180 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
182 // During routing, we only consider paths shorter than our maximum length estimate.
183 // In the legacy onion format, the maximum number of hops used to be a fixed value of 20.
184 // However, in the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
185 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
186 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
188 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
189 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
190 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
191 // (payment_secret and total_msat) = 93 bytes for the final hop.
192 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
193 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
194 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
196 /// The recipient of a payment.
197 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
198 pub struct PaymentParameters {
199 /// The node id of the payee.
200 pub payee_pubkey: PublicKey,
202 /// Features supported by the payee.
204 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
205 /// does not contain any features.
207 /// [`for_keysend`]: Self::for_keysend
208 pub features: Option<InvoiceFeatures>,
210 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
211 pub route_hints: Vec<RouteHint>,
213 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
214 pub expiry_time: Option<u64>,
216 /// The maximum total CLTV delta we accept for the route.
217 pub max_total_cltv_expiry_delta: u32,
220 impl_writeable_tlv_based!(PaymentParameters, {
221 (0, payee_pubkey, required),
222 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
223 (2, features, option),
224 (4, route_hints, vec_type),
225 (6, expiry_time, option),
228 impl PaymentParameters {
229 /// Creates a payee with the node id of the given `pubkey`.
230 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
236 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
240 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
241 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
242 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
245 /// Includes the payee's features.
247 /// (C-not exported) since bindings don't support move semantics
248 pub fn with_features(self, features: InvoiceFeatures) -> Self {
249 Self { features: Some(features), ..self }
252 /// Includes hints for routing to the payee.
254 /// (C-not exported) since bindings don't support move semantics
255 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
256 Self { route_hints, ..self }
259 /// Includes a payment expiration in seconds relative to the UNIX epoch.
261 /// (C-not exported) since bindings don't support move semantics
262 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
263 Self { expiry_time: Some(expiry_time), ..self }
266 /// Includes a limit for the total CLTV expiry delta which is considered during routing
268 /// (C-not exported) since bindings don't support move semantics
269 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
270 Self { max_total_cltv_expiry_delta, ..self }
274 /// A list of hops along a payment path terminating with a channel to the recipient.
275 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
276 pub struct RouteHint(pub Vec<RouteHintHop>);
278 impl Writeable for RouteHint {
279 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
280 (self.0.len() as u64).write(writer)?;
281 for hop in self.0.iter() {
288 impl Readable for RouteHint {
289 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
290 let hop_count: u64 = Readable::read(reader)?;
291 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
292 for _ in 0..hop_count {
293 hops.push(Readable::read(reader)?);
299 /// A channel descriptor for a hop along a payment path.
300 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
301 pub struct RouteHintHop {
302 /// The node_id of the non-target end of the route
303 pub src_node_id: PublicKey,
304 /// The short_channel_id of this channel
305 pub short_channel_id: u64,
306 /// The fees which must be paid to use this channel
307 pub fees: RoutingFees,
308 /// The difference in CLTV values between this node and the next node.
309 pub cltv_expiry_delta: u16,
310 /// The minimum value, in msat, which must be relayed to the next hop.
311 pub htlc_minimum_msat: Option<u64>,
312 /// The maximum value in msat available for routing with a single HTLC.
313 pub htlc_maximum_msat: Option<u64>,
316 impl_writeable_tlv_based!(RouteHintHop, {
317 (0, src_node_id, required),
318 (1, htlc_minimum_msat, option),
319 (2, short_channel_id, required),
320 (3, htlc_maximum_msat, option),
322 (6, cltv_expiry_delta, required),
325 #[derive(Eq, PartialEq)]
326 struct RouteGraphNode {
328 lowest_fee_to_peer_through_node: u64,
329 lowest_fee_to_node: u64,
330 total_cltv_delta: u32,
331 // The maximum value a yet-to-be-constructed payment path might flow through this node.
332 // This value is upper-bounded by us by:
333 // - how much is needed for a path being constructed
334 // - how much value can channels following this node (up to the destination) can contribute,
335 // considering their capacity and fees
336 value_contribution_msat: u64,
337 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
338 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
339 path_htlc_minimum_msat: u64,
340 /// All penalties incurred from this hop on the way to the destination, as calculated using
342 path_penalty_msat: u64,
343 /// The number of hops walked up to this node.
344 path_length_to_node: u8,
347 impl cmp::Ord for RouteGraphNode {
348 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
349 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
350 .saturating_add(other.path_penalty_msat);
351 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
352 .saturating_add(self.path_penalty_msat);
353 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
357 impl cmp::PartialOrd for RouteGraphNode {
358 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
359 Some(self.cmp(other))
363 /// A wrapper around the various hop representations.
365 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
366 #[derive(Clone, Debug)]
367 enum CandidateRouteHop<'a> {
368 /// A hop from the payer, where the outbound liquidity is known.
370 details: &'a ChannelDetails,
372 /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
374 info: DirectedChannelInfoWithUpdate<'a>,
375 short_channel_id: u64,
377 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
379 hint: &'a RouteHintHop,
383 impl<'a> CandidateRouteHop<'a> {
384 fn short_channel_id(&self) -> u64 {
386 CandidateRouteHop::FirstHop { details } => details.short_channel_id.unwrap(),
387 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
388 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
392 // NOTE: This may alloc memory so avoid calling it in a hot code path.
393 fn features(&self) -> ChannelFeatures {
395 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
396 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
397 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
401 fn cltv_expiry_delta(&self) -> u32 {
403 CandidateRouteHop::FirstHop { .. } => 0,
404 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
405 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
409 fn htlc_minimum_msat(&self) -> u64 {
411 CandidateRouteHop::FirstHop { .. } => 0,
412 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
413 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
417 fn htlc_maximum_msat(&self) -> u64 {
419 CandidateRouteHop::FirstHop { details } => details.next_outbound_htlc_limit_msat,
420 CandidateRouteHop::PublicHop { info, .. } => info.htlc_maximum_msat(),
421 CandidateRouteHop::PrivateHop { hint } => {
422 hint.htlc_maximum_msat.unwrap_or(u64::max_value())
427 fn fees(&self) -> RoutingFees {
429 CandidateRouteHop::FirstHop { .. } => RoutingFees {
430 base_msat: 0, proportional_millionths: 0,
432 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
433 CandidateRouteHop::PrivateHop { hint } => hint.fees,
437 fn effective_capacity(&self) -> EffectiveCapacity {
439 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
440 liquidity_msat: details.next_outbound_htlc_limit_msat,
442 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
443 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
448 /// It's useful to keep track of the hops associated with the fees required to use them,
449 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
450 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
451 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
453 struct PathBuildingHop<'a> {
454 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
455 // is a larger refactor and will require careful performance analysis.
457 candidate: CandidateRouteHop<'a>,
460 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
461 src_lowest_inbound_fees: RoutingFees,
462 /// All the fees paid *after* this channel on the way to the destination
463 next_hops_fee_msat: u64,
464 /// Fee paid for the use of the current channel (see candidate.fees()).
465 /// The value will be actually deducted from the counterparty balance on the previous link.
466 hop_use_fee_msat: u64,
467 /// Used to compare channels when choosing the for routing.
468 /// Includes paying for the use of a hop and the following hops, as well as
469 /// an estimated cost of reaching this hop.
470 /// Might get stale when fees are recomputed. Primarily for internal use.
472 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
473 /// walk and may be invalid thereafter.
474 path_htlc_minimum_msat: u64,
475 /// All penalties incurred from this channel on the way to the destination, as calculated using
477 path_penalty_msat: u64,
478 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
479 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
480 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
481 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
482 /// avoid processing them again.
484 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
485 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
486 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
487 // value_contribution_msat, which requires tracking it here. See comments below where it is
488 // used for more info.
489 value_contribution_msat: u64,
492 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
493 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
494 let mut debug_struct = f.debug_struct("PathBuildingHop");
496 .field("node_id", &self.node_id)
497 .field("short_channel_id", &self.candidate.short_channel_id())
498 .field("total_fee_msat", &self.total_fee_msat)
499 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
500 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
501 .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)))
502 .field("path_penalty_msat", &self.path_penalty_msat)
503 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
504 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
505 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
506 let debug_struct = debug_struct
507 .field("value_contribution_msat", &self.value_contribution_msat);
508 debug_struct.finish()
512 // Instantiated with a list of hops with correct data in them collected during path finding,
513 // an instance of this struct should be further modified only via given methods.
515 struct PaymentPath<'a> {
516 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
519 impl<'a> PaymentPath<'a> {
520 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
521 fn get_value_msat(&self) -> u64 {
522 self.hops.last().unwrap().0.fee_msat
525 fn get_path_penalty_msat(&self) -> u64 {
526 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
529 fn get_total_fee_paid_msat(&self) -> u64 {
530 if self.hops.len() < 1 {
534 // Can't use next_hops_fee_msat because it gets outdated.
535 for (i, (hop, _)) in self.hops.iter().enumerate() {
536 if i != self.hops.len() - 1 {
537 result += hop.fee_msat;
543 fn get_cost_msat(&self) -> u64 {
544 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
547 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
548 // to change fees may result in an inconsistency.
550 // Sometimes we call this function right after constructing a path which is inconsistent in
551 // that it the value being transferred has decreased while we were doing path finding, leading
552 // to the fees being paid not lining up with the actual limits.
554 // Note that this function is not aware of the available_liquidity limit, and thus does not
555 // support increasing the value being transferred.
556 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
557 assert!(value_msat <= self.hops.last().unwrap().0.fee_msat);
559 let mut total_fee_paid_msat = 0 as u64;
560 for i in (0..self.hops.len()).rev() {
561 let last_hop = i == self.hops.len() - 1;
563 // For non-last-hop, this value will represent the fees paid on the current hop. It
564 // will consist of the fees for the use of the next hop, and extra fees to match
565 // htlc_minimum_msat of the current channel. Last hop is handled separately.
566 let mut cur_hop_fees_msat = 0;
568 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
571 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
572 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
573 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
574 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
575 // set it too high just to maliciously take more fees by exploiting this
576 // match htlc_minimum_msat logic.
577 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
578 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
579 // Note that there is a risk that *previous hops* (those closer to us, as we go
580 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
582 // This might make us end up with a broken route, although this should be super-rare
583 // in practice, both because of how healthy channels look like, and how we pick
584 // channels in add_entry.
585 // Also, this can't be exploited more heavily than *announce a free path and fail
587 cur_hop_transferred_amount_msat += extra_fees_msat;
588 total_fee_paid_msat += extra_fees_msat;
589 cur_hop_fees_msat += extra_fees_msat;
593 // Final hop is a special case: it usually has just value_msat (by design), but also
594 // it still could overpay for the htlc_minimum_msat.
595 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
597 // Propagate updated fees for the use of the channels to one hop back, where they
598 // will be actually paid (fee_msat). The last hop is handled above separately.
599 cur_hop.fee_msat = cur_hop_fees_msat;
602 // Fee for the use of the current hop which will be deducted on the previous hop.
603 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
604 // this channel is free for us.
606 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
607 cur_hop.hop_use_fee_msat = new_fee;
608 total_fee_paid_msat += new_fee;
610 // It should not be possible because this function is called only to reduce the
611 // value. In that case, compute_fee was already called with the same fees for
612 // larger amount and there was no overflow.
620 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
621 let proportional_fee_millions =
622 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
623 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
624 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
628 // This function may be (indirectly) called without any verification,
629 // with channel_fees provided by a caller. We should handle it gracefully.
634 /// The default `features` we assume for a node in a route, when no `features` are known about that
637 /// Default features are:
638 /// * variable_length_onion_optional
639 fn default_node_features() -> NodeFeatures {
640 let mut features = NodeFeatures::empty();
641 features.set_variable_length_onion_optional();
645 /// Finds a route from us (payer) to the given target node (payee).
647 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
648 /// Without this, MPP will only be used if the payee's features are available in the network graph.
650 /// Private routing paths between a public node and the target may be included in `params.payee`.
652 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
653 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
654 /// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
656 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
657 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
658 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
662 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
663 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
668 /// Panics if first_hops contains channels without short_channel_ids;
669 /// [`ChannelManager::list_usable_channels`] will never include such channels.
671 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
672 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
673 pub fn find_route<L: Deref, S: Score>(
674 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network: &NetworkGraph,
675 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
676 ) -> Result<Route, LightningError>
677 where L::Target: Logger {
678 let network_graph = network.read_only();
680 our_node_pubkey, &route_params.payment_params, &network_graph, first_hops, route_params.final_value_msat,
681 route_params.final_cltv_expiry_delta, logger, scorer, random_seed_bytes
684 add_random_cltv_offset(&mut route, &route_params.payment_params, &network_graph, random_seed_bytes);
687 Err(err) => Err(err),
691 pub(crate) fn get_route<L: Deref, S: Score>(
692 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
693 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
694 logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
695 ) -> Result<Route, LightningError>
696 where L::Target: Logger {
697 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
698 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
700 if payee_node_id == our_node_id {
701 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
704 if final_value_msat > MAX_VALUE_MSAT {
705 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
708 if final_value_msat == 0 {
709 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
712 for route in payment_params.route_hints.iter() {
713 for hop in &route.0 {
714 if hop.src_node_id == payment_params.payee_pubkey {
715 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
719 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
720 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});
723 // The general routing idea is the following:
724 // 1. Fill first/last hops communicated by the caller.
725 // 2. Attempt to construct a path from payer to payee for transferring
726 // any ~sufficient (described later) value.
727 // If succeed, remember which channels were used and how much liquidity they have available,
728 // so that future paths don't rely on the same liquidity.
729 // 3. Proceed to the next step if:
730 // - we hit the recommended target value;
731 // - OR if we could not construct a new path. Any next attempt will fail too.
732 // Otherwise, repeat step 2.
733 // 4. See if we managed to collect paths which aggregately are able to transfer target value
734 // (not recommended value).
735 // 5. If yes, proceed. If not, fail routing.
736 // 6. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
737 // 7. Of all the found paths, select only those with the lowest total fee.
738 // 8. The last path in every selected route is likely to be more than we need.
739 // Reduce its value-to-transfer and recompute fees.
740 // 9. Choose the best route by the lowest total fee.
742 // As for the actual search algorithm,
743 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
744 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
746 // We are not a faithful Dijkstra's implementation because we can change values which impact
747 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
748 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
749 // the value we are currently attempting to send over a path, we simply reduce the value being
750 // sent along the path for any hops after that channel. This may imply that later fees (which
751 // we've already tabulated) are lower because a smaller value is passing through the channels
752 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
753 // channels which were selected earlier (and which may still be used for other paths without a
754 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
757 // One potentially problematic case for this algorithm would be if there are many
758 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
759 // graph walking), we may never find a path which is not liquidity-limited and has lower
760 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
761 // Because we only consider paths with at least 5% of the total value being sent, the damage
762 // from such a case should be limited, however this could be further reduced in the future by
763 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
764 // limits for the purposes of fee calculation.
766 // Alternatively, we could store more detailed path information in the heap (targets, below)
767 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
768 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
769 // and practically (as we would need to store dynamically-allocated path information in heap
770 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
771 // results of such an algorithm would likely be biased towards lower-value paths.
773 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
774 // outside of our current search value, running a path search more times to gather candidate
775 // paths at different values. While this may be acceptable, further path searches may increase
776 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
777 // graph for candidate paths, calculating the maximum value which can realistically be sent at
778 // the same time, remaining generic across different payment values.
780 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
781 // to use as the A* heuristic beyond just the cost to get one node further than the current
784 let network_channels = network_graph.channels();
785 let network_nodes = network_graph.nodes();
787 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
788 // it. If the payee supports it they're supposed to include it in the invoice, so that should
790 let allow_mpp = if let Some(features) = &payment_params.features {
791 features.supports_basic_mpp()
792 } else if let Some(node) = network_nodes.get(&payee_node_id) {
793 if let Some(node_info) = node.announcement_info.as_ref() {
794 node_info.features.supports_basic_mpp()
797 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
798 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
799 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
802 // Prepare the data we'll use for payee-to-payer search by
803 // inserting first hops suggested by the caller as targets.
804 // Our search will then attempt to reach them while traversing from the payee node.
805 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
806 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
807 if let Some(hops) = first_hops {
809 if chan.short_channel_id.is_none() {
810 panic!("first_hops should be filled in with usable channels, not pending ones");
812 if chan.counterparty.node_id == *our_node_pubkey {
813 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
816 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
817 .or_insert(Vec::new())
820 if first_hop_targets.is_empty() {
821 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
825 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
826 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
827 // adding duplicate entries when we find a better path to a given node.
828 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
830 // Map from node_id to information about the best current path to that node, including feerate
832 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
834 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
835 // indicating that we may wish to try again with a higher value, potentially paying to meet an
836 // htlc_minimum with extra fees while still finding a cheaper path.
837 let mut hit_minimum_limit;
839 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
840 // We start with a path_value of the exact amount we want, and if that generates a route we may
841 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
842 // amount we want in total across paths, selecting the best subset at the end.
843 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
844 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
845 let mut path_value_msat = final_value_msat;
847 // Keep track of how much liquidity has been used in selected channels. Used to determine
848 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
849 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
850 // liquidity used in one direction will not offset any used in the opposite direction.
851 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
852 HashMap::with_capacity(network_nodes.len());
854 // Keeping track of how much value we already collected across other paths. Helps to decide:
855 // - how much a new path should be transferring (upper bound);
856 // - whether a channel should be disregarded because
857 // it's available liquidity is too small comparing to how much more we need to collect;
858 // - when we want to stop looking for new paths.
859 let mut already_collected_value_msat = 0;
861 for (_, channels) in first_hop_targets.iter_mut() {
862 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
865 // First, if channels are below `recommended_value_msat`, sort them in descending order,
866 // preferring larger channels to avoid splitting the payment into more MPP parts than is
869 // Second, because simply always sorting in descending order would always use our largest
870 // available outbound capacity, needlessly fragmenting our available channel capacities,
871 // sort channels above `recommended_value_msat` in ascending order, preferring channels
872 // which have enough, but not too much, capacity for the payment.
873 channels.sort_unstable_by(|chan_a, chan_b| {
874 if chan_b.next_outbound_htlc_limit_msat < recommended_value_msat || chan_a.next_outbound_htlc_limit_msat < recommended_value_msat {
875 // Sort in descending order
876 chan_b.next_outbound_htlc_limit_msat.cmp(&chan_a.next_outbound_htlc_limit_msat)
878 // Sort in ascending order
879 chan_a.next_outbound_htlc_limit_msat.cmp(&chan_b.next_outbound_htlc_limit_msat)
884 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
886 macro_rules! add_entry {
887 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
888 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
889 // since that value has to be transferred over this channel.
890 // Returns whether this channel caused an update to `targets`.
891 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
892 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
893 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
894 // We "return" whether we updated the path at the end, via this:
895 let mut did_add_update_path_to_src_node = false;
896 // Channels to self should not be used. This is more of belt-and-suspenders, because in
897 // practice these cases should be caught earlier:
898 // - for regular channels at channel announcement (TODO)
899 // - for first and last hops early in get_route
900 if $src_node_id != $dest_node_id {
901 let short_channel_id = $candidate.short_channel_id();
902 let htlc_maximum_msat = $candidate.htlc_maximum_msat();
904 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
905 // It may be misleading because we might later choose to reduce the value transferred
906 // over these channels, and the channel which was insufficient might become sufficient.
907 // Worst case: we drop a good channel here because it can't cover the high following
908 // fees caused by one expensive channel, but then this channel could have been used
909 // if the amount being transferred over this path is lower.
910 // We do this for now, but this is a subject for removal.
911 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
912 let used_liquidity_msat = used_channel_liquidities
913 .get(&(short_channel_id, $src_node_id < $dest_node_id))
914 .map_or(0, |used_liquidity_msat| {
915 available_value_contribution_msat = available_value_contribution_msat
916 .saturating_sub(*used_liquidity_msat);
920 // Routing Fragmentation Mitigation heuristic:
922 // Routing fragmentation across many payment paths increases the overall routing
923 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
924 // Taking too many smaller paths also increases the chance of payment failure.
925 // Thus to avoid this effect, we require from our collected links to provide
926 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
928 // This requirement is currently 5% of the remaining-to-be-collected value.
929 // This means as we successfully advance in our collection,
930 // the absolute liquidity contribution is lowered,
931 // thus increasing the number of potential channels to be selected.
933 // Derive the minimal liquidity contribution with a ratio of 20 (5%, rounded up)
934 // or 100% if we're not allowed to do multipath payments.
935 let minimal_value_contribution_msat: u64 = if allow_mpp {
936 (recommended_value_msat - already_collected_value_msat + 19) / 20
940 // Verify the liquidity offered by this channel complies to the minimal contribution.
941 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
942 // Do not consider candidate hops that would exceed the maximum path length.
943 let path_length_to_node = $next_hops_path_length + 1;
944 let doesnt_exceed_max_path_length = path_length_to_node <= MAX_PATH_LENGTH_ESTIMATE;
946 // Do not consider candidates that exceed the maximum total cltv expiry limit.
947 // In order to already account for some of the privacy enhancing random CLTV
948 // expiry delta offset we add on top later, we subtract a rough estimate
949 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
950 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
951 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
952 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
953 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
954 .saturating_add($candidate.cltv_expiry_delta());
955 let doesnt_exceed_cltv_delta_limit = hop_total_cltv_delta <= max_total_cltv_expiry_delta;
957 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
958 // Includes paying fees for the use of the following channels.
959 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
960 Some(result) => result,
961 // Can't overflow due to how the values were computed right above.
962 None => unreachable!(),
964 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
965 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
966 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
968 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
969 let may_overpay_to_meet_path_minimum_msat =
970 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
971 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
972 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
973 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
975 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
976 // bother considering this channel. If retrying with recommended_value_msat may
977 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
978 // around again with a higher amount.
979 if contributes_sufficient_value && doesnt_exceed_max_path_length &&
980 doesnt_exceed_cltv_delta_limit && may_overpay_to_meet_path_minimum_msat {
981 hit_minimum_limit = true;
982 } else if contributes_sufficient_value && doesnt_exceed_max_path_length &&
983 doesnt_exceed_cltv_delta_limit && over_path_minimum_msat {
984 // Note that low contribution here (limited by available_liquidity_msat)
985 // might violate htlc_minimum_msat on the hops which are next along the
986 // payment path (upstream to the payee). To avoid that, we recompute
987 // path fees knowing the final path contribution after constructing it.
988 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
989 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
990 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
991 .unwrap_or_else(|| u64::max_value());
992 let hm_entry = dist.entry($src_node_id);
993 let old_entry = hm_entry.or_insert_with(|| {
994 // If there was previously no known way to access the source node
995 // (recall it goes payee-to-payer) of short_channel_id, first add a
996 // semi-dummy record just to compute the fees to reach the source node.
997 // This will affect our decision on selecting short_channel_id
998 // as a way to reach the $dest_node_id.
999 let mut fee_base_msat = 0;
1000 let mut fee_proportional_millionths = 0;
1001 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
1002 fee_base_msat = fees.base_msat;
1003 fee_proportional_millionths = fees.proportional_millionths;
1006 node_id: $dest_node_id.clone(),
1007 candidate: $candidate.clone(),
1009 src_lowest_inbound_fees: RoutingFees {
1010 base_msat: fee_base_msat,
1011 proportional_millionths: fee_proportional_millionths,
1013 next_hops_fee_msat: u64::max_value(),
1014 hop_use_fee_msat: u64::max_value(),
1015 total_fee_msat: u64::max_value(),
1016 path_htlc_minimum_msat,
1017 path_penalty_msat: u64::max_value(),
1018 was_processed: false,
1019 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1020 value_contribution_msat,
1024 #[allow(unused_mut)] // We only use the mut in cfg(test)
1025 let mut should_process = !old_entry.was_processed;
1026 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1028 // In test/fuzzing builds, we do extra checks to make sure the skipping
1029 // of already-seen nodes only happens in cases we expect (see below).
1030 if !should_process { should_process = true; }
1034 let mut hop_use_fee_msat = 0;
1035 let mut total_fee_msat = $next_hops_fee_msat;
1037 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1038 // will have the same effective-fee
1039 if $src_node_id != our_node_id {
1040 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1041 // max_value means we'll always fail
1042 // the old_entry.total_fee_msat > total_fee_msat check
1043 None => total_fee_msat = u64::max_value(),
1045 hop_use_fee_msat = fee_msat;
1046 total_fee_msat += hop_use_fee_msat;
1047 // When calculating the lowest inbound fees to a node, we
1048 // calculate fees here not based on the actual value we think
1049 // will flow over this channel, but on the minimum value that
1050 // we'll accept flowing over it. The minimum accepted value
1051 // is a constant through each path collection run, ensuring
1052 // consistent basis. Otherwise we may later find a
1053 // different path to the source node that is more expensive,
1054 // but which we consider to be cheaper because we are capacity
1055 // constrained and the relative fee becomes lower.
1056 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1057 .map(|a| a.checked_add(total_fee_msat)) {
1062 total_fee_msat = u64::max_value();
1069 let available_liquidity_msat = htlc_maximum_msat - used_liquidity_msat;
1070 let path_penalty_msat = $next_hops_path_penalty_msat.saturating_add(
1071 scorer.channel_penalty_msat(short_channel_id, amount_to_transfer_over_msat,
1072 available_liquidity_msat, &$src_node_id, &$dest_node_id));
1073 let new_graph_node = RouteGraphNode {
1074 node_id: $src_node_id,
1075 lowest_fee_to_peer_through_node: total_fee_msat,
1076 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1077 total_cltv_delta: hop_total_cltv_delta,
1078 value_contribution_msat: value_contribution_msat,
1079 path_htlc_minimum_msat,
1081 path_length_to_node,
1084 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1085 // if this way is cheaper than the already known
1086 // (considering the cost to "reach" this channel from the route destination,
1087 // the cost of using this channel,
1088 // and the cost of routing to the source node of this channel).
1089 // Also, consider that htlc_minimum_msat_difference, because we might end up
1090 // paying it. Consider the following exploit:
1091 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1092 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1093 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1094 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1096 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1097 // but it may require additional tracking - we don't want to double-count
1098 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1099 // can't use something that may decrease on future hops.
1100 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1101 .saturating_add(old_entry.path_penalty_msat);
1102 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1103 .saturating_add(path_penalty_msat);
1105 if !old_entry.was_processed && new_cost < old_cost {
1106 targets.push(new_graph_node);
1107 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1108 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1109 old_entry.total_fee_msat = total_fee_msat;
1110 old_entry.node_id = $dest_node_id.clone();
1111 old_entry.candidate = $candidate.clone();
1112 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1113 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1114 old_entry.path_penalty_msat = path_penalty_msat;
1115 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1117 old_entry.value_contribution_msat = value_contribution_msat;
1119 did_add_update_path_to_src_node = true;
1120 } else if old_entry.was_processed && new_cost < old_cost {
1121 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1123 // If we're skipping processing a node which was previously
1124 // processed even though we found another path to it with a
1125 // cheaper fee, check that it was because the second path we
1126 // found (which we are processing now) has a lower value
1127 // contribution due to an HTLC minimum limit.
1129 // e.g. take a graph with two paths from node 1 to node 2, one
1130 // through channel A, and one through channel B. Channel A and
1131 // B are both in the to-process heap, with their scores set by
1132 // a higher htlc_minimum than fee.
1133 // Channel A is processed first, and the channels onwards from
1134 // node 1 are added to the to-process heap. Thereafter, we pop
1135 // Channel B off of the heap, note that it has a much more
1136 // restrictive htlc_maximum_msat, and recalculate the fees for
1137 // all of node 1's channels using the new, reduced, amount.
1139 // This would be bogus - we'd be selecting a higher-fee path
1140 // with a lower htlc_maximum_msat instead of the one we'd
1141 // already decided to use.
1142 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1144 value_contribution_msat + path_penalty_msat <
1145 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1153 did_add_update_path_to_src_node
1157 let default_node_features = default_node_features();
1159 // Find ways (channels with destination) to reach a given node and store them
1160 // in the corresponding data structures (routing graph etc).
1161 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1162 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1163 // This data can later be helpful to optimize routing (pay lower fees).
1164 macro_rules! add_entries_to_cheapest_to_target_node {
1165 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1166 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1167 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1168 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1169 let was_processed = elem.was_processed;
1170 elem.was_processed = true;
1173 // Entries are added to dist in add_entry!() when there is a channel from a node.
1174 // Because there are no channels from payee, it will not have a dist entry at this point.
1175 // If we're processing any other node, it is always be the result of a channel from it.
1176 assert_eq!($node_id, payee_node_id);
1181 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1182 for details in first_channels {
1183 let candidate = CandidateRouteHop::FirstHop { details };
1184 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1185 $next_hops_value_contribution,
1186 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1187 $next_hops_cltv_delta, $next_hops_path_length);
1191 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1194 &default_node_features
1197 if !features.requires_unknown_bits() {
1198 for chan_id in $node.channels.iter() {
1199 let chan = network_channels.get(chan_id).unwrap();
1200 if !chan.features.requires_unknown_bits() {
1201 let (directed_channel, source) =
1202 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1203 if first_hops.is_none() || *source != our_node_id {
1204 if let Some(direction) = directed_channel.direction() {
1205 if direction.enabled {
1206 let candidate = CandidateRouteHop::PublicHop {
1207 info: directed_channel.with_update().unwrap(),
1208 short_channel_id: *chan_id,
1210 add_entry!(candidate, *source, $node_id,
1211 $fee_to_target_msat,
1212 $next_hops_value_contribution,
1213 $next_hops_path_htlc_minimum_msat,
1214 $next_hops_path_penalty_msat,
1215 $next_hops_cltv_delta, $next_hops_path_length);
1226 let mut payment_paths = Vec::<PaymentPath>::new();
1228 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1229 'paths_collection: loop {
1230 // For every new path, start from scratch, except for used_channel_liquidities, which
1231 // helps to avoid reusing previously selected paths in future iterations.
1234 hit_minimum_limit = false;
1236 // If first hop is a private channel and the only way to reach the payee, this is the only
1237 // place where it could be added.
1238 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1239 for details in first_channels {
1240 let candidate = CandidateRouteHop::FirstHop { details };
1241 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat,
1243 log_trace!(logger, "{} direct route to payee via SCID {}",
1244 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1248 // Add the payee as a target, so that the payee-to-payer
1249 // search algorithm knows what to start with.
1250 match network_nodes.get(&payee_node_id) {
1251 // The payee is not in our network graph, so nothing to add here.
1252 // There is still a chance of reaching them via last_hops though,
1253 // so don't yet fail the payment here.
1254 // If not, targets.pop() will not even let us enter the loop in step 2.
1257 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0, 0);
1262 // If a caller provided us with last hops, add them to routing targets. Since this happens
1263 // earlier than general path finding, they will be somewhat prioritized, although currently
1264 // it matters only if the fees are exactly the same.
1265 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1266 let first_hop_in_route = &(route.0)[0];
1267 let have_hop_src_in_graph =
1268 // Only add the hops in this route to our candidate set if either
1269 // we have a direct channel to the first hop or the first hop is
1270 // in the regular network graph.
1271 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1272 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1273 if have_hop_src_in_graph {
1274 // We start building the path from reverse, i.e., from payee
1275 // to the first RouteHintHop in the path.
1276 let hop_iter = route.0.iter().rev();
1277 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1278 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1279 let mut hop_used = true;
1280 let mut aggregate_next_hops_fee_msat: u64 = 0;
1281 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1282 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1283 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1284 let mut aggregate_next_hops_path_length: u8 = 0;
1286 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1287 let source = NodeId::from_pubkey(&hop.src_node_id);
1288 let target = NodeId::from_pubkey(&prev_hop_id);
1289 let candidate = network_channels
1290 .get(&hop.short_channel_id)
1291 .and_then(|channel| channel.as_directed_to(&target))
1292 .and_then(|(channel, _)| channel.with_update())
1293 .map(|info| CandidateRouteHop::PublicHop {
1295 short_channel_id: hop.short_channel_id,
1297 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1299 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat,
1300 path_value_msat, aggregate_next_hops_path_htlc_minimum_msat,
1301 aggregate_next_hops_path_penalty_msat,
1302 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length) {
1303 // If this hop was not used then there is no use checking the preceding
1304 // hops in the RouteHint. We can break by just searching for a direct
1305 // channel between last checked hop and first_hop_targets.
1309 let amount_to_transfer_msat = final_value_msat + aggregate_next_hops_fee_msat;
1310 let capacity_msat = candidate.effective_capacity().as_msat();
1311 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1312 .saturating_add(scorer.channel_penalty_msat(hop.short_channel_id, amount_to_transfer_msat, capacity_msat, &source, &target));
1314 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1315 .saturating_add(hop.cltv_expiry_delta as u32);
1317 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1320 // Searching for a direct channel between last checked hop and first_hop_targets
1321 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1322 for details in first_channels {
1323 let candidate = CandidateRouteHop::FirstHop { details };
1324 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1325 aggregate_next_hops_fee_msat, path_value_msat,
1326 aggregate_next_hops_path_htlc_minimum_msat,
1327 aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta,
1328 aggregate_next_hops_path_length);
1336 // In the next values of the iterator, the aggregate fees already reflects
1337 // the sum of value sent from payer (final_value_msat) and routing fees
1338 // for the last node in the RouteHint. We need to just add the fees to
1339 // route through the current node so that the preceding node (next iteration)
1341 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1342 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1343 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1345 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1346 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1347 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1348 .checked_add(hop_htlc_minimum_msat_inc);
1349 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1351 if idx == route.0.len() - 1 {
1352 // The last hop in this iterator is the first hop in
1353 // overall RouteHint.
1354 // If this hop connects to a node with which we have a direct channel,
1355 // ignore the network graph and, if the last hop was added, add our
1356 // direct channel to the candidate set.
1358 // Note that we *must* check if the last hop was added as `add_entry`
1359 // always assumes that the third argument is a node to which we have a
1361 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1362 for details in first_channels {
1363 let candidate = CandidateRouteHop::FirstHop { details };
1364 add_entry!(candidate, our_node_id,
1365 NodeId::from_pubkey(&hop.src_node_id),
1366 aggregate_next_hops_fee_msat, path_value_msat,
1367 aggregate_next_hops_path_htlc_minimum_msat,
1368 aggregate_next_hops_path_penalty_msat,
1369 aggregate_next_hops_cltv_delta,
1370 aggregate_next_hops_path_length);
1378 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1380 // At this point, targets are filled with the data from first and
1381 // last hops communicated by the caller, and the payment receiver.
1382 let mut found_new_path = false;
1385 // If this loop terminates due the exhaustion of targets, two situations are possible:
1386 // - not enough outgoing liquidity:
1387 // 0 < already_collected_value_msat < final_value_msat
1388 // - enough outgoing liquidity:
1389 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1390 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1391 // paths_collection will be stopped because found_new_path==false.
1392 // This is not necessarily a routing failure.
1393 '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, path_length_to_node, .. }) = targets.pop() {
1395 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1396 // traversing the graph and arrange the path out of what we found.
1397 if node_id == our_node_id {
1398 let mut new_entry = dist.remove(&our_node_id).unwrap();
1399 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1402 let mut features_set = false;
1403 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1404 for details in first_channels {
1405 if details.short_channel_id.unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1406 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1407 features_set = true;
1413 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1414 if let Some(node_info) = node.announcement_info.as_ref() {
1415 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1417 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1420 // We can fill in features for everything except hops which were
1421 // provided via the invoice we're paying. We could guess based on the
1422 // recipient's features but for now we simply avoid guessing at all.
1426 // Means we succesfully traversed from the payer to the payee, now
1427 // save this path for the payment route. Also, update the liquidity
1428 // remaining on the used hops, so that we take them into account
1429 // while looking for more paths.
1430 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1434 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1435 Some(payment_hop) => payment_hop,
1436 // We can't arrive at None because, if we ever add an entry to targets,
1437 // we also fill in the entry in dist (see add_entry!).
1438 None => unreachable!(),
1440 // We "propagate" the fees one hop backward (topologically) here,
1441 // so that fees paid for a HTLC forwarding on the current channel are
1442 // associated with the previous channel (where they will be subtracted).
1443 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1444 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1446 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1447 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1449 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1450 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1452 let mut payment_path = PaymentPath {hops: ordered_hops};
1454 // We could have possibly constructed a slightly inconsistent path: since we reduce
1455 // value being transferred along the way, we could have violated htlc_minimum_msat
1456 // on some channels we already passed (assuming dest->source direction). Here, we
1457 // recompute the fees again, so that if that's the case, we match the currently
1458 // underpaid htlc_minimum_msat with fees.
1459 payment_path.update_value_and_recompute_fees(cmp::min(value_contribution_msat, final_value_msat));
1461 // Since a path allows to transfer as much value as
1462 // the smallest channel it has ("bottleneck"), we should recompute
1463 // the fees so sender HTLC don't overpay fees when traversing
1464 // larger channels than the bottleneck. This may happen because
1465 // when we were selecting those channels we were not aware how much value
1466 // this path will transfer, and the relative fee for them
1467 // might have been computed considering a larger value.
1468 // Remember that we used these channels so that we don't rely
1469 // on the same liquidity in future paths.
1470 let mut prevented_redundant_path_selection = false;
1471 let prev_hop_iter = core::iter::once(&our_node_id)
1472 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
1473 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
1474 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
1475 let used_liquidity_msat = used_channel_liquidities
1476 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
1477 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
1478 .or_insert(spent_on_hop_msat);
1479 if *used_liquidity_msat == hop.candidate.htlc_maximum_msat() {
1480 // If this path used all of this channel's available liquidity, we know
1481 // this path will not be selected again in the next loop iteration.
1482 prevented_redundant_path_selection = true;
1484 debug_assert!(*used_liquidity_msat <= hop.candidate.htlc_maximum_msat());
1486 if !prevented_redundant_path_selection {
1487 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1488 // we'll probably end up picking the same path again on the next iteration.
1489 // Decrease the available liquidity of a hop in the middle of the path.
1490 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1491 let exhausted = u64::max_value();
1492 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1493 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
1494 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
1497 // Track the total amount all our collected paths allow to send so that we:
1498 // - know when to stop looking for more paths
1499 // - know which of the hops are useless considering how much more sats we need
1500 // (contributes_sufficient_value)
1501 already_collected_value_msat += value_contribution_msat;
1503 payment_paths.push(payment_path);
1504 found_new_path = true;
1505 break 'path_construction;
1508 // If we found a path back to the payee, we shouldn't try to process it again. This is
1509 // the equivalent of the `elem.was_processed` check in
1510 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1511 if node_id == payee_node_id { continue 'path_construction; }
1513 // Otherwise, since the current target node is not us,
1514 // keep "unrolling" the payment graph from payee to payer by
1515 // finding a way to reach the current target from the payer side.
1516 match network_nodes.get(&node_id) {
1519 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
1520 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
1521 total_cltv_delta, path_length_to_node);
1527 // If we don't support MPP, no use trying to gather more value ever.
1528 break 'paths_collection;
1532 // Stop either when the recommended value is reached or if no new path was found in this
1534 // In the latter case, making another path finding attempt won't help,
1535 // because we deterministically terminated the search due to low liquidity.
1536 if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1537 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1538 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1539 break 'paths_collection;
1540 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1541 // Further, if this was our first walk of the graph, and we weren't limited by an
1542 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1543 // limited by an htlc_minimum_msat value, find another path with a higher value,
1544 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1545 // still keeping a lower total fee than this path.
1546 if !hit_minimum_limit {
1547 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1548 break 'paths_collection;
1550 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1551 path_value_msat = recommended_value_msat;
1556 if payment_paths.len() == 0 {
1557 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1560 if already_collected_value_msat < final_value_msat {
1561 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1564 // Sort by total fees and take the best paths.
1565 payment_paths.sort_unstable_by_key(|path| path.get_total_fee_paid_msat());
1566 if payment_paths.len() > 50 {
1567 payment_paths.truncate(50);
1570 // Draw multiple sufficient routes by randomly combining the selected paths.
1571 let mut drawn_routes = Vec::new();
1572 let mut prng = ChaCha20::new(random_seed_bytes, &[0u8; 12]);
1573 let mut random_index_bytes = [0u8; ::core::mem::size_of::<usize>()];
1575 let num_permutations = payment_paths.len();
1576 for _ in 0..num_permutations {
1577 let mut cur_route = Vec::<PaymentPath>::new();
1578 let mut aggregate_route_value_msat = 0;
1581 // Do a Fisher-Yates shuffle to create a random permutation of the payment paths
1582 for cur_index in (1..payment_paths.len()).rev() {
1583 prng.process_in_place(&mut random_index_bytes);
1584 let random_index = usize::from_be_bytes(random_index_bytes).wrapping_rem(cur_index+1);
1585 payment_paths.swap(cur_index, random_index);
1589 for payment_path in &payment_paths {
1590 cur_route.push(payment_path.clone());
1591 aggregate_route_value_msat += payment_path.get_value_msat();
1592 if aggregate_route_value_msat > final_value_msat {
1593 // Last path likely overpaid. Substract it from the most expensive
1594 // (in terms of proportional fee) path in this route and recompute fees.
1595 // This might be not the most economically efficient way, but fewer paths
1596 // also makes routing more reliable.
1597 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1599 // First, we drop some expensive low-value paths entirely if possible, since fewer
1600 // paths is better: the payment is less likely to fail. In order to do so, we sort
1601 // by value and fall back to total fees paid, i.e., in case of equal values we
1602 // prefer lower cost paths.
1603 cur_route.sort_unstable_by(|a, b| {
1604 a.get_value_msat().cmp(&b.get_value_msat())
1605 // Reverse ordering for cost, so we drop higher-cost paths first
1606 .then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1609 // We should make sure that at least 1 path left.
1610 let mut paths_left = cur_route.len();
1611 cur_route.retain(|path| {
1612 if paths_left == 1 {
1615 let mut keep = true;
1616 let path_value_msat = path.get_value_msat();
1617 if path_value_msat <= overpaid_value_msat {
1619 overpaid_value_msat -= path_value_msat;
1625 if overpaid_value_msat == 0 {
1629 assert!(cur_route.len() > 0);
1632 // Now, subtract the overpaid value from the most-expensive path.
1633 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1634 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1635 cur_route.sort_unstable_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1636 let expensive_payment_path = cur_route.first_mut().unwrap();
1638 // We already dropped all the small value paths above, meaning all the
1639 // remaining paths are larger than remaining overpaid_value_msat.
1640 // Thus, this can't be negative.
1641 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1642 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1646 drawn_routes.push(cur_route);
1650 // Select the best route by lowest total cost.
1651 drawn_routes.sort_unstable_by_key(|paths| paths.iter().map(|path| path.get_cost_msat()).sum::<u64>());
1652 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1653 for payment_path in drawn_routes.first().unwrap() {
1654 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1656 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)})?,
1657 node_features: node_features.clone(),
1658 short_channel_id: payment_hop.candidate.short_channel_id(),
1659 channel_features: payment_hop.candidate.features(),
1660 fee_msat: payment_hop.fee_msat,
1661 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1663 }).collect::<Vec<_>>();
1664 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1665 // applicable for the previous hop.
1666 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1667 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1669 selected_paths.push(path);
1672 if let Some(features) = &payment_params.features {
1673 for path in selected_paths.iter_mut() {
1674 if let Ok(route_hop) = path.last_mut().unwrap() {
1675 route_hop.node_features = features.to_context();
1681 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1682 payment_params: Some(payment_params.clone()),
1684 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1688 // When an adversarial intermediary node observes a payment, it may be able to infer its
1689 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1690 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1691 // payment path by adding a randomized 'shadow route' offset to the final hop.
1692 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]) {
1693 let network_channels = network_graph.channels();
1694 let network_nodes = network_graph.nodes();
1696 for path in route.paths.iter_mut() {
1697 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1699 // Remember the last three nodes of the random walk and avoid looping back on them.
1700 // Init with the last three nodes from the actual path, if possible.
1701 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1702 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1703 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1705 // Choose the last publicly known node as the starting point for the random walk.
1706 let mut cur_hop: Option<NodeId> = None;
1707 let mut path_nonce = [0u8; 12];
1708 if let Some(starting_hop) = path.iter().rev()
1709 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1710 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1711 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1714 // Init PRNG with the path-dependant nonce, which is static for private paths.
1715 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1716 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1718 // Pick a random path length in [1 .. 3]
1719 prng.process_in_place(&mut random_path_bytes);
1720 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1722 for random_hop in 0..random_walk_length {
1723 // If we don't find a suitable offset in the public network graph, we default to
1724 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1725 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1727 if let Some(cur_node_id) = cur_hop {
1728 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1729 // Randomly choose the next unvisited hop.
1730 prng.process_in_place(&mut random_path_bytes);
1731 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1732 .checked_rem(cur_node.channels.len())
1733 .and_then(|index| cur_node.channels.get(index))
1734 .and_then(|id| network_channels.get(id)) {
1735 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1736 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1737 nodes_to_avoid[random_hop] = *next_id;
1738 dir_info.direction().map(|channel_update_info| {
1739 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1740 cur_hop = Some(*next_id);
1748 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1749 .checked_add(random_hop_offset)
1750 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1753 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1754 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1755 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1757 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1758 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1759 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1760 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1761 max_path_offset = cmp::max(
1762 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1763 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1764 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1766 // Add 'shadow' CLTV offset to the final hop
1767 if let Some(last_hop) = path.last_mut() {
1768 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1769 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1776 use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
1777 use routing::router::{get_route, add_random_cltv_offset, default_node_features,
1778 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
1779 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
1780 use routing::scoring::Score;
1781 use chain::transaction::OutPoint;
1782 use chain::keysinterface::KeysInterface;
1783 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1784 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1785 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1786 use ln::channelmanager;
1787 use util::test_utils;
1788 use util::chacha20::ChaCha20;
1789 use util::ser::Writeable;
1791 use util::ser::Writer;
1793 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1794 use bitcoin::hashes::Hash;
1795 use bitcoin::network::constants::Network;
1796 use bitcoin::blockdata::constants::genesis_block;
1797 use bitcoin::blockdata::script::Builder;
1798 use bitcoin::blockdata::opcodes;
1799 use bitcoin::blockdata::transaction::TxOut;
1803 use bitcoin::secp256k1::{PublicKey,SecretKey};
1804 use bitcoin::secp256k1::{Secp256k1, All};
1807 use sync::{self, Arc};
1809 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1810 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1811 channelmanager::ChannelDetails {
1812 channel_id: [0; 32],
1813 counterparty: channelmanager::ChannelCounterparty {
1816 unspendable_punishment_reserve: 0,
1817 forwarding_info: None,
1818 outbound_htlc_minimum_msat: None,
1819 outbound_htlc_maximum_msat: None,
1821 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1824 inbound_scid_alias: None,
1825 channel_value_satoshis: 0,
1828 outbound_capacity_msat,
1829 next_outbound_htlc_limit_msat: outbound_capacity_msat,
1830 inbound_capacity_msat: 42,
1831 unspendable_punishment_reserve: None,
1832 confirmations_required: None,
1833 force_close_spend_delay: None,
1834 is_outbound: true, is_funding_locked: true,
1835 is_usable: true, is_public: true,
1836 inbound_htlc_minimum_msat: None,
1837 inbound_htlc_maximum_msat: None,
1841 // Using the same keys for LN and BTC ids
1843 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1844 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
1846 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
1847 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
1849 let unsigned_announcement = UnsignedChannelAnnouncement {
1851 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1855 bitcoin_key_1: node_id_1,
1856 bitcoin_key_2: node_id_2,
1857 excess_data: Vec::new(),
1860 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1861 let valid_announcement = ChannelAnnouncement {
1862 node_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
1863 node_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
1864 bitcoin_signature_1: secp_ctx.sign_ecdsa(&msghash, node_1_privkey),
1865 bitcoin_signature_2: secp_ctx.sign_ecdsa(&msghash, node_2_privkey),
1866 contents: unsigned_announcement.clone(),
1868 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
1869 Ok(res) => assert!(res),
1875 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1876 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
1878 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
1879 let valid_channel_update = ChannelUpdate {
1880 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
1881 contents: update.clone()
1884 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
1885 Ok(res) => assert!(res),
1890 fn add_or_update_node(
1891 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1892 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
1894 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
1895 let unsigned_announcement = UnsignedNodeAnnouncement {
1901 addresses: Vec::new(),
1902 excess_address_data: Vec::new(),
1903 excess_data: Vec::new(),
1905 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1906 let valid_announcement = NodeAnnouncement {
1907 signature: secp_ctx.sign_ecdsa(&msghash, node_privkey),
1908 contents: unsigned_announcement.clone()
1911 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
1917 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
1918 let privkeys: Vec<SecretKey> = (2..22).map(|i| {
1919 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
1922 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
1924 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
1925 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
1927 (our_privkey, our_id, privkeys, pubkeys)
1930 fn id_to_feature_flags(id: u8) -> Vec<u8> {
1931 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1932 // test for it later.
1933 let idx = (id - 1) * 2 + 1;
1935 vec![1 << (idx - 8*3), 0, 0, 0]
1936 } else if idx > 8*2 {
1937 vec![1 << (idx - 8*2), 0, 0]
1938 } else if idx > 8*1 {
1939 vec![1 << (idx - 8*1), 0]
1945 fn build_line_graph() -> (
1946 Secp256k1<All>, sync::Arc<NetworkGraph>, NetGraphMsgHandler<sync::Arc<NetworkGraph>,
1947 sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
1948 sync::Arc<test_utils::TestChainSource>, sync::Arc<test_utils::TestLogger>,
1950 let secp_ctx = Secp256k1::new();
1951 let logger = Arc::new(test_utils::TestLogger::new());
1952 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
1953 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
1954 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
1956 // Build network from our_id to node 19:
1957 // our_id -1(1)2- node0 -1(2)2- node1 - ... - node19
1958 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
1960 for (idx, (cur_privkey, next_privkey)) in core::iter::once(&our_privkey)
1961 .chain(privkeys.iter()).zip(privkeys.iter()).enumerate() {
1962 let cur_short_channel_id = (idx as u64) + 1;
1963 add_channel(&net_graph_msg_handler, &secp_ctx, &cur_privkey, &next_privkey,
1964 ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), cur_short_channel_id);
1965 update_channel(&net_graph_msg_handler, &secp_ctx, &cur_privkey, UnsignedChannelUpdate {
1966 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1967 short_channel_id: cur_short_channel_id,
1968 timestamp: idx as u32,
1970 cltv_expiry_delta: 0,
1971 htlc_minimum_msat: 0,
1972 htlc_maximum_msat: OptionalField::Absent,
1974 fee_proportional_millionths: 0,
1975 excess_data: Vec::new()
1977 update_channel(&net_graph_msg_handler, &secp_ctx, &next_privkey, UnsignedChannelUpdate {
1978 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1979 short_channel_id: cur_short_channel_id,
1980 timestamp: (idx as u32)+1,
1982 cltv_expiry_delta: 0,
1983 htlc_minimum_msat: 0,
1984 htlc_maximum_msat: OptionalField::Absent,
1986 fee_proportional_millionths: 0,
1987 excess_data: Vec::new()
1989 add_or_update_node(&net_graph_msg_handler, &secp_ctx, next_privkey,
1990 NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
1993 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
1996 fn build_graph() -> (
1998 sync::Arc<NetworkGraph>,
1999 NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
2000 sync::Arc<test_utils::TestChainSource>,
2001 sync::Arc<test_utils::TestLogger>,
2003 let secp_ctx = Secp256k1::new();
2004 let logger = Arc::new(test_utils::TestLogger::new());
2005 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
2006 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
2007 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
2008 // Build network from our_id to node6:
2010 // -1(1)2- node0 -1(3)2-
2012 // our_id -1(12)2- node7 -1(13)2--- node2
2014 // -1(2)2- node1 -1(4)2-
2017 // chan1 1-to-2: disabled
2018 // chan1 2-to-1: enabled, 0 fee
2020 // chan2 1-to-2: enabled, ignored fee
2021 // chan2 2-to-1: enabled, 0 fee
2023 // chan3 1-to-2: enabled, 0 fee
2024 // chan3 2-to-1: enabled, 100 msat fee
2026 // chan4 1-to-2: enabled, 100% fee
2027 // chan4 2-to-1: enabled, 0 fee
2029 // chan12 1-to-2: enabled, ignored fee
2030 // chan12 2-to-1: enabled, 0 fee
2032 // chan13 1-to-2: enabled, 200% fee
2033 // chan13 2-to-1: enabled, 0 fee
2036 // -1(5)2- node3 -1(8)2--
2040 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
2042 // -1(7)2- node5 -1(10)2-
2044 // Channels 5, 8, 9 and 10 are private channels.
2046 // chan5 1-to-2: enabled, 100 msat fee
2047 // chan5 2-to-1: enabled, 0 fee
2049 // chan6 1-to-2: enabled, 0 fee
2050 // chan6 2-to-1: enabled, 0 fee
2052 // chan7 1-to-2: enabled, 100% fee
2053 // chan7 2-to-1: enabled, 0 fee
2055 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
2056 // chan8 2-to-1: enabled, 0 fee
2058 // chan9 1-to-2: enabled, 1001 msat fee
2059 // chan9 2-to-1: enabled, 0 fee
2061 // chan10 1-to-2: enabled, 0 fee
2062 // chan10 2-to-1: enabled, 0 fee
2064 // chan11 1-to-2: enabled, 0 fee
2065 // chan11 2-to-1: enabled, 0 fee
2067 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
2069 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
2070 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2071 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2072 short_channel_id: 1,
2075 cltv_expiry_delta: 0,
2076 htlc_minimum_msat: 0,
2077 htlc_maximum_msat: OptionalField::Absent,
2079 fee_proportional_millionths: 0,
2080 excess_data: Vec::new()
2083 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
2085 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
2086 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2087 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2088 short_channel_id: 2,
2091 cltv_expiry_delta: (5 << 4) | 3,
2092 htlc_minimum_msat: 0,
2093 htlc_maximum_msat: OptionalField::Absent,
2094 fee_base_msat: u32::max_value(),
2095 fee_proportional_millionths: u32::max_value(),
2096 excess_data: Vec::new()
2098 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2099 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2100 short_channel_id: 2,
2103 cltv_expiry_delta: 0,
2104 htlc_minimum_msat: 0,
2105 htlc_maximum_msat: OptionalField::Absent,
2107 fee_proportional_millionths: 0,
2108 excess_data: Vec::new()
2111 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
2113 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
2114 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2115 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2116 short_channel_id: 12,
2119 cltv_expiry_delta: (5 << 4) | 3,
2120 htlc_minimum_msat: 0,
2121 htlc_maximum_msat: OptionalField::Absent,
2122 fee_base_msat: u32::max_value(),
2123 fee_proportional_millionths: u32::max_value(),
2124 excess_data: Vec::new()
2126 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2127 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2128 short_channel_id: 12,
2131 cltv_expiry_delta: 0,
2132 htlc_minimum_msat: 0,
2133 htlc_maximum_msat: OptionalField::Absent,
2135 fee_proportional_millionths: 0,
2136 excess_data: Vec::new()
2139 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
2141 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
2142 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2144 short_channel_id: 3,
2147 cltv_expiry_delta: (3 << 4) | 1,
2148 htlc_minimum_msat: 0,
2149 htlc_maximum_msat: OptionalField::Absent,
2151 fee_proportional_millionths: 0,
2152 excess_data: Vec::new()
2154 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2156 short_channel_id: 3,
2159 cltv_expiry_delta: (3 << 4) | 2,
2160 htlc_minimum_msat: 0,
2161 htlc_maximum_msat: OptionalField::Absent,
2163 fee_proportional_millionths: 0,
2164 excess_data: Vec::new()
2167 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2168 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2169 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2170 short_channel_id: 4,
2173 cltv_expiry_delta: (4 << 4) | 1,
2174 htlc_minimum_msat: 0,
2175 htlc_maximum_msat: OptionalField::Absent,
2177 fee_proportional_millionths: 1000000,
2178 excess_data: Vec::new()
2180 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2181 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2182 short_channel_id: 4,
2185 cltv_expiry_delta: (4 << 4) | 2,
2186 htlc_minimum_msat: 0,
2187 htlc_maximum_msat: OptionalField::Absent,
2189 fee_proportional_millionths: 0,
2190 excess_data: Vec::new()
2193 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2194 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2195 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2196 short_channel_id: 13,
2199 cltv_expiry_delta: (13 << 4) | 1,
2200 htlc_minimum_msat: 0,
2201 htlc_maximum_msat: OptionalField::Absent,
2203 fee_proportional_millionths: 2000000,
2204 excess_data: Vec::new()
2206 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2207 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2208 short_channel_id: 13,
2211 cltv_expiry_delta: (13 << 4) | 2,
2212 htlc_minimum_msat: 0,
2213 htlc_maximum_msat: OptionalField::Absent,
2215 fee_proportional_millionths: 0,
2216 excess_data: Vec::new()
2219 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2221 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2222 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2223 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2224 short_channel_id: 6,
2227 cltv_expiry_delta: (6 << 4) | 1,
2228 htlc_minimum_msat: 0,
2229 htlc_maximum_msat: OptionalField::Absent,
2231 fee_proportional_millionths: 0,
2232 excess_data: Vec::new()
2234 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2235 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2236 short_channel_id: 6,
2239 cltv_expiry_delta: (6 << 4) | 2,
2240 htlc_minimum_msat: 0,
2241 htlc_maximum_msat: OptionalField::Absent,
2243 fee_proportional_millionths: 0,
2244 excess_data: Vec::new(),
2247 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2248 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2249 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2250 short_channel_id: 11,
2253 cltv_expiry_delta: (11 << 4) | 1,
2254 htlc_minimum_msat: 0,
2255 htlc_maximum_msat: OptionalField::Absent,
2257 fee_proportional_millionths: 0,
2258 excess_data: Vec::new()
2260 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2261 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2262 short_channel_id: 11,
2265 cltv_expiry_delta: (11 << 4) | 2,
2266 htlc_minimum_msat: 0,
2267 htlc_maximum_msat: OptionalField::Absent,
2269 fee_proportional_millionths: 0,
2270 excess_data: Vec::new()
2273 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2275 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2277 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2278 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2279 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2280 short_channel_id: 7,
2283 cltv_expiry_delta: (7 << 4) | 1,
2284 htlc_minimum_msat: 0,
2285 htlc_maximum_msat: OptionalField::Absent,
2287 fee_proportional_millionths: 1000000,
2288 excess_data: Vec::new()
2290 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2291 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2292 short_channel_id: 7,
2295 cltv_expiry_delta: (7 << 4) | 2,
2296 htlc_minimum_msat: 0,
2297 htlc_maximum_msat: OptionalField::Absent,
2299 fee_proportional_millionths: 0,
2300 excess_data: Vec::new()
2303 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2305 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
2309 fn simple_route_test() {
2310 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2311 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2312 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2313 let scorer = test_utils::TestScorer::with_penalty(0);
2314 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2315 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2317 // Simple route to 2 via 1
2319 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) {
2320 assert_eq!(err, "Cannot send a payment of 0 msat");
2321 } else { panic!(); }
2323 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2324 assert_eq!(route.paths[0].len(), 2);
2326 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2327 assert_eq!(route.paths[0][0].short_channel_id, 2);
2328 assert_eq!(route.paths[0][0].fee_msat, 100);
2329 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2330 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2331 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2333 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2334 assert_eq!(route.paths[0][1].short_channel_id, 4);
2335 assert_eq!(route.paths[0][1].fee_msat, 100);
2336 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2337 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2338 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2342 fn invalid_first_hop_test() {
2343 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2344 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2345 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2346 let scorer = test_utils::TestScorer::with_penalty(0);
2347 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2348 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2350 // Simple route to 2 via 1
2352 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2354 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2355 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) {
2356 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2357 } else { panic!(); }
2359 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2360 assert_eq!(route.paths[0].len(), 2);
2364 fn htlc_minimum_test() {
2365 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2366 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2367 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2368 let scorer = test_utils::TestScorer::with_penalty(0);
2369 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2370 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2372 // Simple route to 2 via 1
2374 // Disable other paths
2375 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2376 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2377 short_channel_id: 12,
2379 flags: 2, // to disable
2380 cltv_expiry_delta: 0,
2381 htlc_minimum_msat: 0,
2382 htlc_maximum_msat: OptionalField::Absent,
2384 fee_proportional_millionths: 0,
2385 excess_data: Vec::new()
2387 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2388 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2389 short_channel_id: 3,
2391 flags: 2, // to disable
2392 cltv_expiry_delta: 0,
2393 htlc_minimum_msat: 0,
2394 htlc_maximum_msat: OptionalField::Absent,
2396 fee_proportional_millionths: 0,
2397 excess_data: Vec::new()
2399 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2400 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2401 short_channel_id: 13,
2403 flags: 2, // to disable
2404 cltv_expiry_delta: 0,
2405 htlc_minimum_msat: 0,
2406 htlc_maximum_msat: OptionalField::Absent,
2408 fee_proportional_millionths: 0,
2409 excess_data: Vec::new()
2411 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2412 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2413 short_channel_id: 6,
2415 flags: 2, // to disable
2416 cltv_expiry_delta: 0,
2417 htlc_minimum_msat: 0,
2418 htlc_maximum_msat: OptionalField::Absent,
2420 fee_proportional_millionths: 0,
2421 excess_data: Vec::new()
2423 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2424 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2425 short_channel_id: 7,
2427 flags: 2, // to disable
2428 cltv_expiry_delta: 0,
2429 htlc_minimum_msat: 0,
2430 htlc_maximum_msat: OptionalField::Absent,
2432 fee_proportional_millionths: 0,
2433 excess_data: Vec::new()
2436 // Check against amount_to_transfer_over_msat.
2437 // Set minimal HTLC of 200_000_000 msat.
2438 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2439 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2440 short_channel_id: 2,
2443 cltv_expiry_delta: 0,
2444 htlc_minimum_msat: 200_000_000,
2445 htlc_maximum_msat: OptionalField::Absent,
2447 fee_proportional_millionths: 0,
2448 excess_data: Vec::new()
2451 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2453 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2454 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2455 short_channel_id: 4,
2458 cltv_expiry_delta: 0,
2459 htlc_minimum_msat: 0,
2460 htlc_maximum_msat: OptionalField::Present(199_999_999),
2462 fee_proportional_millionths: 0,
2463 excess_data: Vec::new()
2466 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2467 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) {
2468 assert_eq!(err, "Failed to find a path to the given destination");
2469 } else { panic!(); }
2471 // Lift the restriction on the first hop.
2472 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2473 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2474 short_channel_id: 2,
2477 cltv_expiry_delta: 0,
2478 htlc_minimum_msat: 0,
2479 htlc_maximum_msat: OptionalField::Absent,
2481 fee_proportional_millionths: 0,
2482 excess_data: Vec::new()
2485 // A payment above the minimum should pass
2486 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();
2487 assert_eq!(route.paths[0].len(), 2);
2491 fn htlc_minimum_overpay_test() {
2492 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2493 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2494 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2495 let scorer = test_utils::TestScorer::with_penalty(0);
2496 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2497 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2499 // A route to node#2 via two paths.
2500 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2501 // Thus, they can't send 60 without overpaying.
2502 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2503 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2504 short_channel_id: 2,
2507 cltv_expiry_delta: 0,
2508 htlc_minimum_msat: 35_000,
2509 htlc_maximum_msat: OptionalField::Present(40_000),
2511 fee_proportional_millionths: 0,
2512 excess_data: Vec::new()
2514 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2515 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2516 short_channel_id: 12,
2519 cltv_expiry_delta: 0,
2520 htlc_minimum_msat: 35_000,
2521 htlc_maximum_msat: OptionalField::Present(40_000),
2523 fee_proportional_millionths: 0,
2524 excess_data: Vec::new()
2528 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2530 short_channel_id: 13,
2533 cltv_expiry_delta: 0,
2534 htlc_minimum_msat: 0,
2535 htlc_maximum_msat: OptionalField::Absent,
2537 fee_proportional_millionths: 0,
2538 excess_data: Vec::new()
2540 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2541 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2542 short_channel_id: 4,
2545 cltv_expiry_delta: 0,
2546 htlc_minimum_msat: 0,
2547 htlc_maximum_msat: OptionalField::Absent,
2549 fee_proportional_millionths: 0,
2550 excess_data: Vec::new()
2553 // Disable other paths
2554 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2555 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2556 short_channel_id: 1,
2558 flags: 2, // to disable
2559 cltv_expiry_delta: 0,
2560 htlc_minimum_msat: 0,
2561 htlc_maximum_msat: OptionalField::Absent,
2563 fee_proportional_millionths: 0,
2564 excess_data: Vec::new()
2567 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2568 // Overpay fees to hit htlc_minimum_msat.
2569 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2570 // TODO: this could be better balanced to overpay 10k and not 15k.
2571 assert_eq!(overpaid_fees, 15_000);
2573 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2574 // while taking even more fee to match htlc_minimum_msat.
2575 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2577 short_channel_id: 12,
2580 cltv_expiry_delta: 0,
2581 htlc_minimum_msat: 65_000,
2582 htlc_maximum_msat: OptionalField::Present(80_000),
2584 fee_proportional_millionths: 0,
2585 excess_data: Vec::new()
2587 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2588 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2589 short_channel_id: 2,
2592 cltv_expiry_delta: 0,
2593 htlc_minimum_msat: 0,
2594 htlc_maximum_msat: OptionalField::Absent,
2596 fee_proportional_millionths: 0,
2597 excess_data: Vec::new()
2599 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2600 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2601 short_channel_id: 4,
2604 cltv_expiry_delta: 0,
2605 htlc_minimum_msat: 0,
2606 htlc_maximum_msat: OptionalField::Absent,
2608 fee_proportional_millionths: 100_000,
2609 excess_data: Vec::new()
2612 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2613 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2614 assert_eq!(route.paths.len(), 1);
2615 assert_eq!(route.paths[0][0].short_channel_id, 12);
2616 let fees = route.paths[0][0].fee_msat;
2617 assert_eq!(fees, 5_000);
2619 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2620 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2621 // the other channel.
2622 assert_eq!(route.paths.len(), 1);
2623 assert_eq!(route.paths[0][0].short_channel_id, 2);
2624 let fees = route.paths[0][0].fee_msat;
2625 assert_eq!(fees, 5_000);
2629 fn disable_channels_test() {
2630 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2631 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2632 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2633 let scorer = test_utils::TestScorer::with_penalty(0);
2634 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2635 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2637 // // Disable channels 4 and 12 by flags=2
2638 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2639 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2640 short_channel_id: 4,
2642 flags: 2, // to disable
2643 cltv_expiry_delta: 0,
2644 htlc_minimum_msat: 0,
2645 htlc_maximum_msat: OptionalField::Absent,
2647 fee_proportional_millionths: 0,
2648 excess_data: Vec::new()
2650 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2651 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2652 short_channel_id: 12,
2654 flags: 2, // to disable
2655 cltv_expiry_delta: 0,
2656 htlc_minimum_msat: 0,
2657 htlc_maximum_msat: OptionalField::Absent,
2659 fee_proportional_millionths: 0,
2660 excess_data: Vec::new()
2663 // If all the channels require some features we don't understand, route should fail
2664 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) {
2665 assert_eq!(err, "Failed to find a path to the given destination");
2666 } else { panic!(); }
2668 // If we specify a channel to node7, that overrides our local channel view and that gets used
2669 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2670 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();
2671 assert_eq!(route.paths[0].len(), 2);
2673 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2674 assert_eq!(route.paths[0][0].short_channel_id, 42);
2675 assert_eq!(route.paths[0][0].fee_msat, 200);
2676 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2677 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2678 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2680 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2681 assert_eq!(route.paths[0][1].short_channel_id, 13);
2682 assert_eq!(route.paths[0][1].fee_msat, 100);
2683 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2684 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2685 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2689 fn disable_node_test() {
2690 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2691 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2692 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2693 let scorer = test_utils::TestScorer::with_penalty(0);
2694 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2695 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2697 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2698 let mut unknown_features = NodeFeatures::known();
2699 unknown_features.set_unknown_feature_required();
2700 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2701 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2702 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2704 // If all nodes require some features we don't understand, route should fail
2705 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) {
2706 assert_eq!(err, "Failed to find a path to the given destination");
2707 } else { panic!(); }
2709 // If we specify a channel to node7, that overrides our local channel view and that gets used
2710 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2711 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();
2712 assert_eq!(route.paths[0].len(), 2);
2714 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2715 assert_eq!(route.paths[0][0].short_channel_id, 42);
2716 assert_eq!(route.paths[0][0].fee_msat, 200);
2717 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2718 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2719 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2721 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2722 assert_eq!(route.paths[0][1].short_channel_id, 13);
2723 assert_eq!(route.paths[0][1].fee_msat, 100);
2724 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2725 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2726 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2728 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2729 // naively) assume that the user checked the feature bits on the invoice, which override
2730 // the node_announcement.
2734 fn our_chans_test() {
2735 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2736 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2737 let scorer = test_utils::TestScorer::with_penalty(0);
2738 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2739 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2741 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2742 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2743 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2744 assert_eq!(route.paths[0].len(), 3);
2746 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2747 assert_eq!(route.paths[0][0].short_channel_id, 2);
2748 assert_eq!(route.paths[0][0].fee_msat, 200);
2749 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2750 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2751 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2753 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2754 assert_eq!(route.paths[0][1].short_channel_id, 4);
2755 assert_eq!(route.paths[0][1].fee_msat, 100);
2756 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2757 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2758 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2760 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2761 assert_eq!(route.paths[0][2].short_channel_id, 3);
2762 assert_eq!(route.paths[0][2].fee_msat, 100);
2763 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2764 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2765 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2767 // If we specify a channel to node7, that overrides our local channel view and that gets used
2768 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2769 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2770 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();
2771 assert_eq!(route.paths[0].len(), 2);
2773 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2774 assert_eq!(route.paths[0][0].short_channel_id, 42);
2775 assert_eq!(route.paths[0][0].fee_msat, 200);
2776 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2777 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2778 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2780 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2781 assert_eq!(route.paths[0][1].short_channel_id, 13);
2782 assert_eq!(route.paths[0][1].fee_msat, 100);
2783 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2784 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2785 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2788 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2789 let zero_fees = RoutingFees {
2791 proportional_millionths: 0,
2793 vec![RouteHint(vec![RouteHintHop {
2794 src_node_id: nodes[3],
2795 short_channel_id: 8,
2797 cltv_expiry_delta: (8 << 4) | 1,
2798 htlc_minimum_msat: None,
2799 htlc_maximum_msat: None,
2801 ]), RouteHint(vec![RouteHintHop {
2802 src_node_id: nodes[4],
2803 short_channel_id: 9,
2806 proportional_millionths: 0,
2808 cltv_expiry_delta: (9 << 4) | 1,
2809 htlc_minimum_msat: None,
2810 htlc_maximum_msat: None,
2811 }]), RouteHint(vec![RouteHintHop {
2812 src_node_id: nodes[5],
2813 short_channel_id: 10,
2815 cltv_expiry_delta: (10 << 4) | 1,
2816 htlc_minimum_msat: None,
2817 htlc_maximum_msat: None,
2821 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2822 let zero_fees = RoutingFees {
2824 proportional_millionths: 0,
2826 vec![RouteHint(vec![RouteHintHop {
2827 src_node_id: nodes[2],
2828 short_channel_id: 5,
2831 proportional_millionths: 0,
2833 cltv_expiry_delta: (5 << 4) | 1,
2834 htlc_minimum_msat: None,
2835 htlc_maximum_msat: None,
2837 src_node_id: nodes[3],
2838 short_channel_id: 8,
2840 cltv_expiry_delta: (8 << 4) | 1,
2841 htlc_minimum_msat: None,
2842 htlc_maximum_msat: None,
2844 ]), RouteHint(vec![RouteHintHop {
2845 src_node_id: nodes[4],
2846 short_channel_id: 9,
2849 proportional_millionths: 0,
2851 cltv_expiry_delta: (9 << 4) | 1,
2852 htlc_minimum_msat: None,
2853 htlc_maximum_msat: None,
2854 }]), RouteHint(vec![RouteHintHop {
2855 src_node_id: nodes[5],
2856 short_channel_id: 10,
2858 cltv_expiry_delta: (10 << 4) | 1,
2859 htlc_minimum_msat: None,
2860 htlc_maximum_msat: None,
2865 fn partial_route_hint_test() {
2866 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2867 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2868 let scorer = test_utils::TestScorer::with_penalty(0);
2869 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2870 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2872 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2873 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2874 // RouteHint may be partially used by the algo to build the best path.
2876 // First check that last hop can't have its source as the payee.
2877 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2878 src_node_id: nodes[6],
2879 short_channel_id: 8,
2882 proportional_millionths: 0,
2884 cltv_expiry_delta: (8 << 4) | 1,
2885 htlc_minimum_msat: None,
2886 htlc_maximum_msat: None,
2889 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2890 invalid_last_hops.push(invalid_last_hop);
2892 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2893 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) {
2894 assert_eq!(err, "Route hint cannot have the payee as the source.");
2895 } else { panic!(); }
2898 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2899 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2900 assert_eq!(route.paths[0].len(), 5);
2902 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2903 assert_eq!(route.paths[0][0].short_channel_id, 2);
2904 assert_eq!(route.paths[0][0].fee_msat, 100);
2905 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2906 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2907 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2909 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2910 assert_eq!(route.paths[0][1].short_channel_id, 4);
2911 assert_eq!(route.paths[0][1].fee_msat, 0);
2912 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2913 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2914 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2916 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2917 assert_eq!(route.paths[0][2].short_channel_id, 6);
2918 assert_eq!(route.paths[0][2].fee_msat, 0);
2919 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2920 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2921 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2923 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2924 assert_eq!(route.paths[0][3].short_channel_id, 11);
2925 assert_eq!(route.paths[0][3].fee_msat, 0);
2926 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2927 // If we have a peer in the node map, we'll use their features here since we don't have
2928 // a way of figuring out their features from the invoice:
2929 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2930 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2932 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2933 assert_eq!(route.paths[0][4].short_channel_id, 8);
2934 assert_eq!(route.paths[0][4].fee_msat, 100);
2935 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2936 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2937 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2940 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2941 let zero_fees = RoutingFees {
2943 proportional_millionths: 0,
2945 vec![RouteHint(vec![RouteHintHop {
2946 src_node_id: nodes[3],
2947 short_channel_id: 8,
2949 cltv_expiry_delta: (8 << 4) | 1,
2950 htlc_minimum_msat: None,
2951 htlc_maximum_msat: None,
2952 }]), RouteHint(vec![
2954 ]), RouteHint(vec![RouteHintHop {
2955 src_node_id: nodes[5],
2956 short_channel_id: 10,
2958 cltv_expiry_delta: (10 << 4) | 1,
2959 htlc_minimum_msat: None,
2960 htlc_maximum_msat: None,
2965 fn ignores_empty_last_hops_test() {
2966 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2967 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2968 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2969 let scorer = test_utils::TestScorer::with_penalty(0);
2970 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2971 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2973 // Test handling of an empty RouteHint passed in Invoice.
2975 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2976 assert_eq!(route.paths[0].len(), 5);
2978 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2979 assert_eq!(route.paths[0][0].short_channel_id, 2);
2980 assert_eq!(route.paths[0][0].fee_msat, 100);
2981 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2982 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2983 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2985 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2986 assert_eq!(route.paths[0][1].short_channel_id, 4);
2987 assert_eq!(route.paths[0][1].fee_msat, 0);
2988 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2989 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2990 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2992 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2993 assert_eq!(route.paths[0][2].short_channel_id, 6);
2994 assert_eq!(route.paths[0][2].fee_msat, 0);
2995 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2996 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2997 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2999 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3000 assert_eq!(route.paths[0][3].short_channel_id, 11);
3001 assert_eq!(route.paths[0][3].fee_msat, 0);
3002 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3003 // If we have a peer in the node map, we'll use their features here since we don't have
3004 // a way of figuring out their features from the invoice:
3005 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3006 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3008 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3009 assert_eq!(route.paths[0][4].short_channel_id, 8);
3010 assert_eq!(route.paths[0][4].fee_msat, 100);
3011 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3012 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3013 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3016 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
3018 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
3019 let zero_fees = RoutingFees {
3021 proportional_millionths: 0,
3023 vec![RouteHint(vec![RouteHintHop {
3024 src_node_id: hint_hops[0],
3025 short_channel_id: 0xff00,
3028 proportional_millionths: 0,
3030 cltv_expiry_delta: (5 << 4) | 1,
3031 htlc_minimum_msat: None,
3032 htlc_maximum_msat: None,
3034 src_node_id: hint_hops[1],
3035 short_channel_id: 0xff01,
3037 cltv_expiry_delta: (8 << 4) | 1,
3038 htlc_minimum_msat: None,
3039 htlc_maximum_msat: None,
3044 fn multi_hint_last_hops_test() {
3045 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3046 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3047 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
3048 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3049 let scorer = test_utils::TestScorer::with_penalty(0);
3050 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3051 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3052 // Test through channels 2, 3, 0xff00, 0xff01.
3053 // Test shows that multiple hop hints are considered.
3055 // Disabling channels 6 & 7 by flags=2
3056 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3057 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3058 short_channel_id: 6,
3060 flags: 2, // to disable
3061 cltv_expiry_delta: 0,
3062 htlc_minimum_msat: 0,
3063 htlc_maximum_msat: OptionalField::Absent,
3065 fee_proportional_millionths: 0,
3066 excess_data: Vec::new()
3068 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3069 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3070 short_channel_id: 7,
3072 flags: 2, // to disable
3073 cltv_expiry_delta: 0,
3074 htlc_minimum_msat: 0,
3075 htlc_maximum_msat: OptionalField::Absent,
3077 fee_proportional_millionths: 0,
3078 excess_data: Vec::new()
3081 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3082 assert_eq!(route.paths[0].len(), 4);
3084 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3085 assert_eq!(route.paths[0][0].short_channel_id, 2);
3086 assert_eq!(route.paths[0][0].fee_msat, 200);
3087 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3088 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3089 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3091 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3092 assert_eq!(route.paths[0][1].short_channel_id, 4);
3093 assert_eq!(route.paths[0][1].fee_msat, 100);
3094 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3095 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3096 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3098 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
3099 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3100 assert_eq!(route.paths[0][2].fee_msat, 0);
3101 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3102 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
3103 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3105 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3106 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3107 assert_eq!(route.paths[0][3].fee_msat, 100);
3108 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3109 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3110 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3114 fn private_multi_hint_last_hops_test() {
3115 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3116 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3118 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3119 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3121 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3122 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3123 let scorer = test_utils::TestScorer::with_penalty(0);
3124 // Test through channels 2, 3, 0xff00, 0xff01.
3125 // Test shows that multiple hop hints are considered.
3127 // Disabling channels 6 & 7 by flags=2
3128 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3129 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3130 short_channel_id: 6,
3132 flags: 2, // to disable
3133 cltv_expiry_delta: 0,
3134 htlc_minimum_msat: 0,
3135 htlc_maximum_msat: OptionalField::Absent,
3137 fee_proportional_millionths: 0,
3138 excess_data: Vec::new()
3140 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3141 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3142 short_channel_id: 7,
3144 flags: 2, // to disable
3145 cltv_expiry_delta: 0,
3146 htlc_minimum_msat: 0,
3147 htlc_maximum_msat: OptionalField::Absent,
3149 fee_proportional_millionths: 0,
3150 excess_data: Vec::new()
3153 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3154 assert_eq!(route.paths[0].len(), 4);
3156 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3157 assert_eq!(route.paths[0][0].short_channel_id, 2);
3158 assert_eq!(route.paths[0][0].fee_msat, 200);
3159 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3160 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3161 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3163 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3164 assert_eq!(route.paths[0][1].short_channel_id, 4);
3165 assert_eq!(route.paths[0][1].fee_msat, 100);
3166 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3167 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3168 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3170 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3171 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3172 assert_eq!(route.paths[0][2].fee_msat, 0);
3173 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3174 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3175 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3177 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3178 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3179 assert_eq!(route.paths[0][3].fee_msat, 100);
3180 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3181 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3182 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3185 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3186 let zero_fees = RoutingFees {
3188 proportional_millionths: 0,
3190 vec![RouteHint(vec![RouteHintHop {
3191 src_node_id: nodes[4],
3192 short_channel_id: 11,
3194 cltv_expiry_delta: (11 << 4) | 1,
3195 htlc_minimum_msat: None,
3196 htlc_maximum_msat: None,
3198 src_node_id: nodes[3],
3199 short_channel_id: 8,
3201 cltv_expiry_delta: (8 << 4) | 1,
3202 htlc_minimum_msat: None,
3203 htlc_maximum_msat: None,
3204 }]), RouteHint(vec![RouteHintHop {
3205 src_node_id: nodes[4],
3206 short_channel_id: 9,
3209 proportional_millionths: 0,
3211 cltv_expiry_delta: (9 << 4) | 1,
3212 htlc_minimum_msat: None,
3213 htlc_maximum_msat: None,
3214 }]), RouteHint(vec![RouteHintHop {
3215 src_node_id: nodes[5],
3216 short_channel_id: 10,
3218 cltv_expiry_delta: (10 << 4) | 1,
3219 htlc_minimum_msat: None,
3220 htlc_maximum_msat: None,
3225 fn last_hops_with_public_channel_test() {
3226 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3227 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3228 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3229 let scorer = test_utils::TestScorer::with_penalty(0);
3230 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3231 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3232 // This test shows that public routes can be present in the invoice
3233 // which would be handled in the same manner.
3235 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3236 assert_eq!(route.paths[0].len(), 5);
3238 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3239 assert_eq!(route.paths[0][0].short_channel_id, 2);
3240 assert_eq!(route.paths[0][0].fee_msat, 100);
3241 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3242 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3243 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3245 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3246 assert_eq!(route.paths[0][1].short_channel_id, 4);
3247 assert_eq!(route.paths[0][1].fee_msat, 0);
3248 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3249 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3250 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3252 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3253 assert_eq!(route.paths[0][2].short_channel_id, 6);
3254 assert_eq!(route.paths[0][2].fee_msat, 0);
3255 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3256 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3257 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3259 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3260 assert_eq!(route.paths[0][3].short_channel_id, 11);
3261 assert_eq!(route.paths[0][3].fee_msat, 0);
3262 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3263 // If we have a peer in the node map, we'll use their features here since we don't have
3264 // a way of figuring out their features from the invoice:
3265 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3266 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3268 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3269 assert_eq!(route.paths[0][4].short_channel_id, 8);
3270 assert_eq!(route.paths[0][4].fee_msat, 100);
3271 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3272 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3273 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3277 fn our_chans_last_hop_connect_test() {
3278 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3279 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3280 let scorer = test_utils::TestScorer::with_penalty(0);
3281 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3282 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3284 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3285 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3286 let mut last_hops = last_hops(&nodes);
3287 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3288 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();
3289 assert_eq!(route.paths[0].len(), 2);
3291 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3292 assert_eq!(route.paths[0][0].short_channel_id, 42);
3293 assert_eq!(route.paths[0][0].fee_msat, 0);
3294 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3295 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3296 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3298 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3299 assert_eq!(route.paths[0][1].short_channel_id, 8);
3300 assert_eq!(route.paths[0][1].fee_msat, 100);
3301 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3302 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3303 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3305 last_hops[0].0[0].fees.base_msat = 1000;
3307 // Revert to via 6 as the fee on 8 goes up
3308 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3309 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3310 assert_eq!(route.paths[0].len(), 4);
3312 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3313 assert_eq!(route.paths[0][0].short_channel_id, 2);
3314 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3315 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3316 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3317 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3319 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3320 assert_eq!(route.paths[0][1].short_channel_id, 4);
3321 assert_eq!(route.paths[0][1].fee_msat, 100);
3322 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3323 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3324 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3326 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3327 assert_eq!(route.paths[0][2].short_channel_id, 7);
3328 assert_eq!(route.paths[0][2].fee_msat, 0);
3329 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3330 // If we have a peer in the node map, we'll use their features here since we don't have
3331 // a way of figuring out their features from the invoice:
3332 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3333 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3335 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3336 assert_eq!(route.paths[0][3].short_channel_id, 10);
3337 assert_eq!(route.paths[0][3].fee_msat, 100);
3338 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3339 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3340 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3342 // ...but still use 8 for larger payments as 6 has a variable feerate
3343 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3344 assert_eq!(route.paths[0].len(), 5);
3346 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3347 assert_eq!(route.paths[0][0].short_channel_id, 2);
3348 assert_eq!(route.paths[0][0].fee_msat, 3000);
3349 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3350 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3351 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3353 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3354 assert_eq!(route.paths[0][1].short_channel_id, 4);
3355 assert_eq!(route.paths[0][1].fee_msat, 0);
3356 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3357 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3358 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3360 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3361 assert_eq!(route.paths[0][2].short_channel_id, 6);
3362 assert_eq!(route.paths[0][2].fee_msat, 0);
3363 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3364 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3365 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3367 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3368 assert_eq!(route.paths[0][3].short_channel_id, 11);
3369 assert_eq!(route.paths[0][3].fee_msat, 1000);
3370 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3371 // If we have a peer in the node map, we'll use their features here since we don't have
3372 // a way of figuring out their features from the invoice:
3373 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3374 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3376 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3377 assert_eq!(route.paths[0][4].short_channel_id, 8);
3378 assert_eq!(route.paths[0][4].fee_msat, 2000);
3379 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3380 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3381 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3384 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> {
3385 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3386 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3387 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3389 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3390 let last_hops = RouteHint(vec![RouteHintHop {
3391 src_node_id: middle_node_id,
3392 short_channel_id: 8,
3395 proportional_millionths: last_hop_fee_prop,
3397 cltv_expiry_delta: (8 << 4) | 1,
3398 htlc_minimum_msat: None,
3399 htlc_maximum_msat: last_hop_htlc_max,
3401 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3402 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3403 let scorer = test_utils::TestScorer::with_penalty(0);
3404 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3405 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3406 get_route(&source_node_id, &payment_params, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()).read_only(),
3407 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes)
3411 fn unannounced_path_test() {
3412 // We should be able to send a payment to a destination without any help of a routing graph
3413 // if we have a channel with a common counterparty that appears in the first and last hop
3415 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3417 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3418 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3419 assert_eq!(route.paths[0].len(), 2);
3421 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3422 assert_eq!(route.paths[0][0].short_channel_id, 42);
3423 assert_eq!(route.paths[0][0].fee_msat, 1001);
3424 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3425 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3426 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3428 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3429 assert_eq!(route.paths[0][1].short_channel_id, 8);
3430 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3431 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3432 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3433 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3437 fn overflow_unannounced_path_test_liquidity_underflow() {
3438 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3439 // the last-hop had a fee which overflowed a u64, we'd panic.
3440 // This was due to us adding the first-hop from us unconditionally, causing us to think
3441 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3442 // In this test, we previously hit a subtraction underflow due to having less available
3443 // liquidity at the last hop than 0.
3444 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());
3448 fn overflow_unannounced_path_test_feerate_overflow() {
3449 // This tests for the same case as above, except instead of hitting a subtraction
3450 // underflow, we hit a case where the fee charged at a hop overflowed.
3451 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());
3455 fn available_amount_while_routing_test() {
3456 // Tests whether we choose the correct available channel amount while routing.
3458 let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
3459 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3460 let scorer = test_utils::TestScorer::with_penalty(0);
3461 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3462 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3463 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3465 // We will use a simple single-path route from
3466 // our node to node2 via node0: channels {1, 3}.
3468 // First disable all other paths.
3469 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3470 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3471 short_channel_id: 2,
3474 cltv_expiry_delta: 0,
3475 htlc_minimum_msat: 0,
3476 htlc_maximum_msat: OptionalField::Present(100_000),
3478 fee_proportional_millionths: 0,
3479 excess_data: Vec::new()
3481 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3482 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3483 short_channel_id: 12,
3486 cltv_expiry_delta: 0,
3487 htlc_minimum_msat: 0,
3488 htlc_maximum_msat: OptionalField::Present(100_000),
3490 fee_proportional_millionths: 0,
3491 excess_data: Vec::new()
3494 // Make the first channel (#1) very permissive,
3495 // and we will be testing all limits on the second channel.
3496 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3497 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3498 short_channel_id: 1,
3501 cltv_expiry_delta: 0,
3502 htlc_minimum_msat: 0,
3503 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3505 fee_proportional_millionths: 0,
3506 excess_data: Vec::new()
3509 // First, let's see if routing works if we have absolutely no idea about the available amount.
3510 // In this case, it should be set to 250_000 sats.
3511 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3512 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3513 short_channel_id: 3,
3516 cltv_expiry_delta: 0,
3517 htlc_minimum_msat: 0,
3518 htlc_maximum_msat: OptionalField::Absent,
3520 fee_proportional_millionths: 0,
3521 excess_data: Vec::new()
3525 // Attempt to route more than available results in a failure.
3526 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3527 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3528 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3529 } else { panic!(); }
3533 // Now, attempt to route an exact amount we have should be fine.
3534 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();
3535 assert_eq!(route.paths.len(), 1);
3536 let path = route.paths.last().unwrap();
3537 assert_eq!(path.len(), 2);
3538 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3539 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3542 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3543 // Disable channel #1 and use another first hop.
3544 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3545 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3546 short_channel_id: 1,
3549 cltv_expiry_delta: 0,
3550 htlc_minimum_msat: 0,
3551 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3553 fee_proportional_millionths: 0,
3554 excess_data: Vec::new()
3557 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3558 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3561 // Attempt to route more than available results in a failure.
3562 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3563 &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) {
3564 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3565 } else { panic!(); }
3569 // Now, attempt to route an exact amount we have should be fine.
3570 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();
3571 assert_eq!(route.paths.len(), 1);
3572 let path = route.paths.last().unwrap();
3573 assert_eq!(path.len(), 2);
3574 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3575 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3578 // Enable channel #1 back.
3579 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3580 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3581 short_channel_id: 1,
3584 cltv_expiry_delta: 0,
3585 htlc_minimum_msat: 0,
3586 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3588 fee_proportional_millionths: 0,
3589 excess_data: Vec::new()
3593 // Now let's see if routing works if we know only htlc_maximum_msat.
3594 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3595 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3596 short_channel_id: 3,
3599 cltv_expiry_delta: 0,
3600 htlc_minimum_msat: 0,
3601 htlc_maximum_msat: OptionalField::Present(15_000),
3603 fee_proportional_millionths: 0,
3604 excess_data: Vec::new()
3608 // Attempt to route more than available results in a failure.
3609 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3610 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3611 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3612 } else { panic!(); }
3616 // Now, attempt to route an exact amount we have should be fine.
3617 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3618 assert_eq!(route.paths.len(), 1);
3619 let path = route.paths.last().unwrap();
3620 assert_eq!(path.len(), 2);
3621 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3622 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3625 // Now let's see if routing works if we know only capacity from the UTXO.
3627 // We can't change UTXO capacity on the fly, so we'll disable
3628 // the existing channel and add another one with the capacity we need.
3629 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3630 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3631 short_channel_id: 3,
3634 cltv_expiry_delta: 0,
3635 htlc_minimum_msat: 0,
3636 htlc_maximum_msat: OptionalField::Absent,
3638 fee_proportional_millionths: 0,
3639 excess_data: Vec::new()
3642 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3643 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3644 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3645 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3646 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3648 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3649 net_graph_msg_handler.add_chain_access(Some(chain_monitor));
3651 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3652 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3653 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3654 short_channel_id: 333,
3657 cltv_expiry_delta: (3 << 4) | 1,
3658 htlc_minimum_msat: 0,
3659 htlc_maximum_msat: OptionalField::Absent,
3661 fee_proportional_millionths: 0,
3662 excess_data: Vec::new()
3664 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3665 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3666 short_channel_id: 333,
3669 cltv_expiry_delta: (3 << 4) | 2,
3670 htlc_minimum_msat: 0,
3671 htlc_maximum_msat: OptionalField::Absent,
3673 fee_proportional_millionths: 0,
3674 excess_data: Vec::new()
3678 // Attempt to route more than available results in a failure.
3679 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3680 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3681 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3682 } else { panic!(); }
3686 // Now, attempt to route an exact amount we have should be fine.
3687 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3688 assert_eq!(route.paths.len(), 1);
3689 let path = route.paths.last().unwrap();
3690 assert_eq!(path.len(), 2);
3691 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3692 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3695 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3696 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3697 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3698 short_channel_id: 333,
3701 cltv_expiry_delta: 0,
3702 htlc_minimum_msat: 0,
3703 htlc_maximum_msat: OptionalField::Present(10_000),
3705 fee_proportional_millionths: 0,
3706 excess_data: Vec::new()
3710 // Attempt to route more than available results in a failure.
3711 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3712 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3713 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3714 } else { panic!(); }
3718 // Now, attempt to route an exact amount we have should be fine.
3719 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3720 assert_eq!(route.paths.len(), 1);
3721 let path = route.paths.last().unwrap();
3722 assert_eq!(path.len(), 2);
3723 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3724 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3729 fn available_liquidity_last_hop_test() {
3730 // Check that available liquidity properly limits the path even when only
3731 // one of the latter hops is limited.
3732 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3733 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3734 let scorer = test_utils::TestScorer::with_penalty(0);
3735 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3736 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3737 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3739 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3740 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3741 // Total capacity: 50 sats.
3743 // Disable other potential paths.
3744 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3745 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3746 short_channel_id: 2,
3749 cltv_expiry_delta: 0,
3750 htlc_minimum_msat: 0,
3751 htlc_maximum_msat: OptionalField::Present(100_000),
3753 fee_proportional_millionths: 0,
3754 excess_data: Vec::new()
3756 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3757 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3758 short_channel_id: 7,
3761 cltv_expiry_delta: 0,
3762 htlc_minimum_msat: 0,
3763 htlc_maximum_msat: OptionalField::Present(100_000),
3765 fee_proportional_millionths: 0,
3766 excess_data: Vec::new()
3771 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3772 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3773 short_channel_id: 12,
3776 cltv_expiry_delta: 0,
3777 htlc_minimum_msat: 0,
3778 htlc_maximum_msat: OptionalField::Present(100_000),
3780 fee_proportional_millionths: 0,
3781 excess_data: Vec::new()
3783 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3784 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3785 short_channel_id: 13,
3788 cltv_expiry_delta: 0,
3789 htlc_minimum_msat: 0,
3790 htlc_maximum_msat: OptionalField::Present(100_000),
3792 fee_proportional_millionths: 0,
3793 excess_data: Vec::new()
3796 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3797 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3798 short_channel_id: 6,
3801 cltv_expiry_delta: 0,
3802 htlc_minimum_msat: 0,
3803 htlc_maximum_msat: OptionalField::Present(50_000),
3805 fee_proportional_millionths: 0,
3806 excess_data: Vec::new()
3808 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3809 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3810 short_channel_id: 11,
3813 cltv_expiry_delta: 0,
3814 htlc_minimum_msat: 0,
3815 htlc_maximum_msat: OptionalField::Present(100_000),
3817 fee_proportional_millionths: 0,
3818 excess_data: Vec::new()
3821 // Attempt to route more than available results in a failure.
3822 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3823 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3824 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3825 } else { panic!(); }
3829 // Now, attempt to route 49 sats (just a bit below the capacity).
3830 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3831 assert_eq!(route.paths.len(), 1);
3832 let mut total_amount_paid_msat = 0;
3833 for path in &route.paths {
3834 assert_eq!(path.len(), 4);
3835 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3836 total_amount_paid_msat += path.last().unwrap().fee_msat;
3838 assert_eq!(total_amount_paid_msat, 49_000);
3842 // Attempt to route an exact amount is also fine
3843 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3844 assert_eq!(route.paths.len(), 1);
3845 let mut total_amount_paid_msat = 0;
3846 for path in &route.paths {
3847 assert_eq!(path.len(), 4);
3848 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3849 total_amount_paid_msat += path.last().unwrap().fee_msat;
3851 assert_eq!(total_amount_paid_msat, 50_000);
3856 fn ignore_fee_first_hop_test() {
3857 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3858 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3859 let scorer = test_utils::TestScorer::with_penalty(0);
3860 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3861 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3862 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3864 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3865 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3866 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3867 short_channel_id: 1,
3870 cltv_expiry_delta: 0,
3871 htlc_minimum_msat: 0,
3872 htlc_maximum_msat: OptionalField::Present(100_000),
3873 fee_base_msat: 1_000_000,
3874 fee_proportional_millionths: 0,
3875 excess_data: Vec::new()
3877 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3878 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3879 short_channel_id: 3,
3882 cltv_expiry_delta: 0,
3883 htlc_minimum_msat: 0,
3884 htlc_maximum_msat: OptionalField::Present(50_000),
3886 fee_proportional_millionths: 0,
3887 excess_data: Vec::new()
3891 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3892 assert_eq!(route.paths.len(), 1);
3893 let mut total_amount_paid_msat = 0;
3894 for path in &route.paths {
3895 assert_eq!(path.len(), 2);
3896 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3897 total_amount_paid_msat += path.last().unwrap().fee_msat;
3899 assert_eq!(total_amount_paid_msat, 50_000);
3904 fn simple_mpp_route_test() {
3905 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3906 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3907 let scorer = test_utils::TestScorer::with_penalty(0);
3908 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3909 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3910 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3912 // We need a route consisting of 3 paths:
3913 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3914 // To achieve this, the amount being transferred should be around
3915 // the total capacity of these 3 paths.
3917 // First, we set limits on these (previously unlimited) channels.
3918 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3920 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3921 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3922 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3923 short_channel_id: 1,
3926 cltv_expiry_delta: 0,
3927 htlc_minimum_msat: 0,
3928 htlc_maximum_msat: OptionalField::Present(100_000),
3930 fee_proportional_millionths: 0,
3931 excess_data: Vec::new()
3933 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3934 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3935 short_channel_id: 3,
3938 cltv_expiry_delta: 0,
3939 htlc_minimum_msat: 0,
3940 htlc_maximum_msat: OptionalField::Present(50_000),
3942 fee_proportional_millionths: 0,
3943 excess_data: Vec::new()
3946 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3947 // (total limit 60).
3948 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3949 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3950 short_channel_id: 12,
3953 cltv_expiry_delta: 0,
3954 htlc_minimum_msat: 0,
3955 htlc_maximum_msat: OptionalField::Present(60_000),
3957 fee_proportional_millionths: 0,
3958 excess_data: Vec::new()
3960 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3961 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3962 short_channel_id: 13,
3965 cltv_expiry_delta: 0,
3966 htlc_minimum_msat: 0,
3967 htlc_maximum_msat: OptionalField::Present(60_000),
3969 fee_proportional_millionths: 0,
3970 excess_data: Vec::new()
3973 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3974 // (total capacity 180 sats).
3975 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3976 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3977 short_channel_id: 2,
3980 cltv_expiry_delta: 0,
3981 htlc_minimum_msat: 0,
3982 htlc_maximum_msat: OptionalField::Present(200_000),
3984 fee_proportional_millionths: 0,
3985 excess_data: Vec::new()
3987 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3988 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3989 short_channel_id: 4,
3992 cltv_expiry_delta: 0,
3993 htlc_minimum_msat: 0,
3994 htlc_maximum_msat: OptionalField::Present(180_000),
3996 fee_proportional_millionths: 0,
3997 excess_data: Vec::new()
4001 // Attempt to route more than available results in a failure.
4002 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4003 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4004 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4005 } else { panic!(); }
4009 // Now, attempt to route 250 sats (just a bit below the capacity).
4010 // Our algorithm should provide us with these 3 paths.
4011 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4012 assert_eq!(route.paths.len(), 3);
4013 let mut total_amount_paid_msat = 0;
4014 for path in &route.paths {
4015 assert_eq!(path.len(), 2);
4016 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4017 total_amount_paid_msat += path.last().unwrap().fee_msat;
4019 assert_eq!(total_amount_paid_msat, 250_000);
4023 // Attempt to route an exact amount is also fine
4024 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4025 assert_eq!(route.paths.len(), 3);
4026 let mut total_amount_paid_msat = 0;
4027 for path in &route.paths {
4028 assert_eq!(path.len(), 2);
4029 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4030 total_amount_paid_msat += path.last().unwrap().fee_msat;
4032 assert_eq!(total_amount_paid_msat, 290_000);
4037 fn long_mpp_route_test() {
4038 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4039 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4040 let scorer = test_utils::TestScorer::with_penalty(0);
4041 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4042 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4043 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4045 // We need a route consisting of 3 paths:
4046 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4047 // Note that these paths overlap (channels 5, 12, 13).
4048 // We will route 300 sats.
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),
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 // Attempt to route more than available results in a failure.
4178 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4179 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4180 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4181 } else { panic!(); }
4185 // Now, attempt to route 300 sats (exact amount we can route).
4186 // Our algorithm should provide us with these 3 paths, 100 sats each.
4187 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4188 assert_eq!(route.paths.len(), 3);
4190 let mut total_amount_paid_msat = 0;
4191 for path in &route.paths {
4192 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4193 total_amount_paid_msat += path.last().unwrap().fee_msat;
4195 assert_eq!(total_amount_paid_msat, 300_000);
4201 fn mpp_cheaper_route_test() {
4202 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4203 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4204 let scorer = test_utils::TestScorer::with_penalty(0);
4205 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4206 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4207 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4209 // This test checks that if we have two cheaper paths and one more expensive path,
4210 // so that liquidity-wise any 2 of 3 combination is sufficient,
4211 // two cheaper paths will be taken.
4212 // These paths have equal available liquidity.
4214 // We need a combination of 3 paths:
4215 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4216 // Note that these paths overlap (channels 5, 12, 13).
4217 // Each path will have 100 sats capacity, those channels which
4218 // are used twice will have 200 sats capacity.
4220 // Disable other potential paths.
4221 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4222 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4223 short_channel_id: 2,
4226 cltv_expiry_delta: 0,
4227 htlc_minimum_msat: 0,
4228 htlc_maximum_msat: OptionalField::Present(100_000),
4230 fee_proportional_millionths: 0,
4231 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 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4273 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4274 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4275 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4276 short_channel_id: 5,
4279 cltv_expiry_delta: 0,
4280 htlc_minimum_msat: 0,
4281 htlc_maximum_msat: OptionalField::Present(200_000),
4283 fee_proportional_millionths: 0,
4284 excess_data: Vec::new()
4287 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4288 // Add 100 sats to the capacities of {12, 13}, because these channels
4289 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4290 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4291 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4292 short_channel_id: 12,
4295 cltv_expiry_delta: 0,
4296 htlc_minimum_msat: 0,
4297 htlc_maximum_msat: OptionalField::Present(200_000),
4299 fee_proportional_millionths: 0,
4300 excess_data: Vec::new()
4302 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4303 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4304 short_channel_id: 13,
4307 cltv_expiry_delta: 0,
4308 htlc_minimum_msat: 0,
4309 htlc_maximum_msat: OptionalField::Present(200_000),
4311 fee_proportional_millionths: 0,
4312 excess_data: Vec::new()
4315 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4316 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4317 short_channel_id: 6,
4320 cltv_expiry_delta: 0,
4321 htlc_minimum_msat: 0,
4322 htlc_maximum_msat: OptionalField::Present(100_000),
4323 fee_base_msat: 1_000,
4324 fee_proportional_millionths: 0,
4325 excess_data: Vec::new()
4327 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4328 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4329 short_channel_id: 11,
4332 cltv_expiry_delta: 0,
4333 htlc_minimum_msat: 0,
4334 htlc_maximum_msat: OptionalField::Present(100_000),
4336 fee_proportional_millionths: 0,
4337 excess_data: Vec::new()
4340 // Path via {node7, node2} is channels {12, 13, 5}.
4341 // We already limited them to 200 sats (they are used twice for 100 sats).
4342 // Nothing to do here.
4345 // Now, attempt to route 180 sats.
4346 // Our algorithm should provide us with these 2 paths.
4347 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4348 assert_eq!(route.paths.len(), 2);
4350 let mut total_value_transferred_msat = 0;
4351 let mut total_paid_msat = 0;
4352 for path in &route.paths {
4353 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4354 total_value_transferred_msat += path.last().unwrap().fee_msat;
4356 total_paid_msat += hop.fee_msat;
4359 // If we paid fee, this would be higher.
4360 assert_eq!(total_value_transferred_msat, 180_000);
4361 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4362 assert_eq!(total_fees_paid, 0);
4367 fn fees_on_mpp_route_test() {
4368 // This test makes sure that MPP algorithm properly takes into account
4369 // fees charged on the channels, by making the fees impactful:
4370 // if the fee is not properly accounted for, the behavior is different.
4371 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4372 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4373 let scorer = test_utils::TestScorer::with_penalty(0);
4374 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4375 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4376 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4378 // We need a route consisting of 2 paths:
4379 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4380 // We will route 200 sats, Each path will have 100 sats capacity.
4382 // This test is not particularly stable: e.g.,
4383 // there's a way to route via {node0, node2, node4}.
4384 // It works while pathfinding is deterministic, but can be broken otherwise.
4385 // It's fine to ignore this concern for now.
4387 // Disable other potential paths.
4388 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4389 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4390 short_channel_id: 2,
4393 cltv_expiry_delta: 0,
4394 htlc_minimum_msat: 0,
4395 htlc_maximum_msat: OptionalField::Present(100_000),
4397 fee_proportional_millionths: 0,
4398 excess_data: Vec::new()
4401 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4402 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4403 short_channel_id: 7,
4406 cltv_expiry_delta: 0,
4407 htlc_minimum_msat: 0,
4408 htlc_maximum_msat: OptionalField::Present(100_000),
4410 fee_proportional_millionths: 0,
4411 excess_data: Vec::new()
4414 // Path via {node0, node2} is channels {1, 3, 5}.
4415 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4416 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4417 short_channel_id: 1,
4420 cltv_expiry_delta: 0,
4421 htlc_minimum_msat: 0,
4422 htlc_maximum_msat: OptionalField::Present(100_000),
4424 fee_proportional_millionths: 0,
4425 excess_data: Vec::new()
4427 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4428 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4429 short_channel_id: 3,
4432 cltv_expiry_delta: 0,
4433 htlc_minimum_msat: 0,
4434 htlc_maximum_msat: OptionalField::Present(100_000),
4436 fee_proportional_millionths: 0,
4437 excess_data: Vec::new()
4440 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4441 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4442 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4443 short_channel_id: 5,
4446 cltv_expiry_delta: 0,
4447 htlc_minimum_msat: 0,
4448 htlc_maximum_msat: OptionalField::Present(100_000),
4450 fee_proportional_millionths: 0,
4451 excess_data: Vec::new()
4454 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4455 // All channels should be 100 sats capacity. But for the fee experiment,
4456 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4457 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4458 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4459 // so no matter how large are other channels,
4460 // the whole path will be limited by 100 sats with just these 2 conditions:
4461 // - channel 12 capacity is 250 sats
4462 // - fee for channel 6 is 150 sats
4463 // Let's test this by enforcing these 2 conditions and removing other limits.
4464 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4465 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4466 short_channel_id: 12,
4469 cltv_expiry_delta: 0,
4470 htlc_minimum_msat: 0,
4471 htlc_maximum_msat: OptionalField::Present(250_000),
4473 fee_proportional_millionths: 0,
4474 excess_data: Vec::new()
4476 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4477 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4478 short_channel_id: 13,
4481 cltv_expiry_delta: 0,
4482 htlc_minimum_msat: 0,
4483 htlc_maximum_msat: OptionalField::Absent,
4485 fee_proportional_millionths: 0,
4486 excess_data: Vec::new()
4489 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4490 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4491 short_channel_id: 6,
4494 cltv_expiry_delta: 0,
4495 htlc_minimum_msat: 0,
4496 htlc_maximum_msat: OptionalField::Absent,
4497 fee_base_msat: 150_000,
4498 fee_proportional_millionths: 0,
4499 excess_data: Vec::new()
4501 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4502 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4503 short_channel_id: 11,
4506 cltv_expiry_delta: 0,
4507 htlc_minimum_msat: 0,
4508 htlc_maximum_msat: OptionalField::Absent,
4510 fee_proportional_millionths: 0,
4511 excess_data: Vec::new()
4515 // Attempt to route more than available results in a failure.
4516 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4517 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4518 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4519 } else { panic!(); }
4523 // Now, attempt to route 200 sats (exact amount we can route).
4524 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4525 assert_eq!(route.paths.len(), 2);
4527 let mut total_amount_paid_msat = 0;
4528 for path in &route.paths {
4529 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4530 total_amount_paid_msat += path.last().unwrap().fee_msat;
4532 assert_eq!(total_amount_paid_msat, 200_000);
4533 assert_eq!(route.get_total_fees(), 150_000);
4538 fn mpp_with_last_hops() {
4539 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4540 // via a single last-hop route hint, we'd fail to route if we first collected routes
4541 // totaling close but not quite enough to fund the full payment.
4543 // This was because we considered last-hop hints to have exactly the sought payment amount
4544 // instead of the amount we were trying to collect, needlessly limiting our path searching
4545 // at the very first hop.
4547 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4548 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4549 // to only have the remaining to-collect amount in available liquidity.
4551 // This bug appeared in production in some specific channel configurations.
4552 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4553 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4554 let scorer = test_utils::TestScorer::with_penalty(0);
4555 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4556 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4557 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4558 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4559 src_node_id: nodes[2],
4560 short_channel_id: 42,
4561 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4562 cltv_expiry_delta: 42,
4563 htlc_minimum_msat: None,
4564 htlc_maximum_msat: None,
4567 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4568 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4569 // would first use the no-fee route and then fail to find a path along the second route as
4570 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4571 // under 5% of our payment amount.
4572 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4573 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4574 short_channel_id: 1,
4577 cltv_expiry_delta: (5 << 4) | 5,
4578 htlc_minimum_msat: 0,
4579 htlc_maximum_msat: OptionalField::Present(99_000),
4580 fee_base_msat: u32::max_value(),
4581 fee_proportional_millionths: u32::max_value(),
4582 excess_data: Vec::new()
4584 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4585 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4586 short_channel_id: 2,
4589 cltv_expiry_delta: (5 << 4) | 3,
4590 htlc_minimum_msat: 0,
4591 htlc_maximum_msat: OptionalField::Present(99_000),
4592 fee_base_msat: u32::max_value(),
4593 fee_proportional_millionths: u32::max_value(),
4594 excess_data: Vec::new()
4596 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4598 short_channel_id: 4,
4601 cltv_expiry_delta: (4 << 4) | 1,
4602 htlc_minimum_msat: 0,
4603 htlc_maximum_msat: OptionalField::Absent,
4605 fee_proportional_millionths: 0,
4606 excess_data: Vec::new()
4608 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4609 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4610 short_channel_id: 13,
4612 flags: 0|2, // Channel disabled
4613 cltv_expiry_delta: (13 << 4) | 1,
4614 htlc_minimum_msat: 0,
4615 htlc_maximum_msat: OptionalField::Absent,
4617 fee_proportional_millionths: 2000000,
4618 excess_data: Vec::new()
4621 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4623 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4624 assert_eq!(route.paths.len(), 2);
4625 // Paths are somewhat randomly ordered, but:
4626 // * the first is channel 2 (1 msat fee) -> channel 4 -> channel 42
4627 // * the second is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4628 assert_eq!(route.paths[0][0].short_channel_id, 2);
4629 assert_eq!(route.paths[0][0].fee_msat, 1);
4630 assert_eq!(route.paths[0][2].fee_msat, 1_000);
4631 assert_eq!(route.paths[1][0].short_channel_id, 1);
4632 assert_eq!(route.paths[1][0].fee_msat, 0);
4633 assert_eq!(route.paths[1][2].fee_msat, 99_000);
4634 assert_eq!(route.get_total_fees(), 1);
4635 assert_eq!(route.get_total_amount(), 100_000);
4639 fn drop_lowest_channel_mpp_route_test() {
4640 // This test checks that low-capacity channel is dropped when after
4641 // path finding we realize that we found more capacity than we need.
4642 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4643 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4644 let scorer = test_utils::TestScorer::with_penalty(0);
4645 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4646 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4647 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4649 // We need a route consisting of 3 paths:
4650 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4652 // The first and the second paths should be sufficient, but the third should be
4653 // cheaper, so that we select it but drop later.
4655 // First, we set limits on these (previously unlimited) channels.
4656 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4658 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4659 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4660 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4661 short_channel_id: 1,
4664 cltv_expiry_delta: 0,
4665 htlc_minimum_msat: 0,
4666 htlc_maximum_msat: OptionalField::Present(100_000),
4668 fee_proportional_millionths: 0,
4669 excess_data: Vec::new()
4671 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4672 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4673 short_channel_id: 3,
4676 cltv_expiry_delta: 0,
4677 htlc_minimum_msat: 0,
4678 htlc_maximum_msat: OptionalField::Present(50_000),
4680 fee_proportional_millionths: 0,
4681 excess_data: Vec::new()
4684 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4685 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4686 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4687 short_channel_id: 12,
4690 cltv_expiry_delta: 0,
4691 htlc_minimum_msat: 0,
4692 htlc_maximum_msat: OptionalField::Present(60_000),
4694 fee_proportional_millionths: 0,
4695 excess_data: Vec::new()
4697 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4698 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4699 short_channel_id: 13,
4702 cltv_expiry_delta: 0,
4703 htlc_minimum_msat: 0,
4704 htlc_maximum_msat: OptionalField::Present(60_000),
4706 fee_proportional_millionths: 0,
4707 excess_data: Vec::new()
4710 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4711 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4712 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4713 short_channel_id: 2,
4716 cltv_expiry_delta: 0,
4717 htlc_minimum_msat: 0,
4718 htlc_maximum_msat: OptionalField::Present(20_000),
4720 fee_proportional_millionths: 0,
4721 excess_data: Vec::new()
4723 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4724 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4725 short_channel_id: 4,
4728 cltv_expiry_delta: 0,
4729 htlc_minimum_msat: 0,
4730 htlc_maximum_msat: OptionalField::Present(20_000),
4732 fee_proportional_millionths: 0,
4733 excess_data: Vec::new()
4737 // Attempt to route more than available results in a failure.
4738 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4739 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4740 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4741 } else { panic!(); }
4745 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4746 // Our algorithm should provide us with these 3 paths.
4747 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4748 assert_eq!(route.paths.len(), 3);
4749 let mut total_amount_paid_msat = 0;
4750 for path in &route.paths {
4751 assert_eq!(path.len(), 2);
4752 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4753 total_amount_paid_msat += path.last().unwrap().fee_msat;
4755 assert_eq!(total_amount_paid_msat, 125_000);
4759 // Attempt to route without the last small cheap channel
4760 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4761 assert_eq!(route.paths.len(), 2);
4762 let mut total_amount_paid_msat = 0;
4763 for path in &route.paths {
4764 assert_eq!(path.len(), 2);
4765 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4766 total_amount_paid_msat += path.last().unwrap().fee_msat;
4768 assert_eq!(total_amount_paid_msat, 90_000);
4773 fn min_criteria_consistency() {
4774 // Test that we don't use an inconsistent metric between updating and walking nodes during
4775 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4776 // was updated with a different criterion from the heap sorting, resulting in loops in
4777 // calculated paths. We test for that specific case here.
4779 // We construct a network that looks like this:
4781 // node2 -1(3)2- node3
4785 // node1 -1(5)2- node4 -1(1)2- node6
4791 // We create a loop on the side of our real path - our destination is node 6, with a
4792 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4793 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4794 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4795 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4796 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4797 // "previous hop" being set to node 3, creating a loop in the path.
4798 let secp_ctx = Secp256k1::new();
4799 let logger = Arc::new(test_utils::TestLogger::new());
4800 let network = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
4801 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network), None, Arc::clone(&logger));
4802 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4803 let scorer = test_utils::TestScorer::with_penalty(0);
4804 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4805 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4806 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4808 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4809 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4810 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4811 short_channel_id: 6,
4814 cltv_expiry_delta: (6 << 4) | 0,
4815 htlc_minimum_msat: 0,
4816 htlc_maximum_msat: OptionalField::Absent,
4818 fee_proportional_millionths: 0,
4819 excess_data: Vec::new()
4821 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4823 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4824 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4825 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4826 short_channel_id: 5,
4829 cltv_expiry_delta: (5 << 4) | 0,
4830 htlc_minimum_msat: 0,
4831 htlc_maximum_msat: OptionalField::Absent,
4833 fee_proportional_millionths: 0,
4834 excess_data: Vec::new()
4836 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4838 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4839 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4840 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4841 short_channel_id: 4,
4844 cltv_expiry_delta: (4 << 4) | 0,
4845 htlc_minimum_msat: 0,
4846 htlc_maximum_msat: OptionalField::Absent,
4848 fee_proportional_millionths: 0,
4849 excess_data: Vec::new()
4851 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4853 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4854 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4855 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4856 short_channel_id: 3,
4859 cltv_expiry_delta: (3 << 4) | 0,
4860 htlc_minimum_msat: 0,
4861 htlc_maximum_msat: OptionalField::Absent,
4863 fee_proportional_millionths: 0,
4864 excess_data: Vec::new()
4866 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4868 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4869 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4870 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4871 short_channel_id: 2,
4874 cltv_expiry_delta: (2 << 4) | 0,
4875 htlc_minimum_msat: 0,
4876 htlc_maximum_msat: OptionalField::Absent,
4878 fee_proportional_millionths: 0,
4879 excess_data: Vec::new()
4882 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4883 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4884 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4885 short_channel_id: 1,
4888 cltv_expiry_delta: (1 << 4) | 0,
4889 htlc_minimum_msat: 100,
4890 htlc_maximum_msat: OptionalField::Absent,
4892 fee_proportional_millionths: 0,
4893 excess_data: Vec::new()
4895 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4898 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4899 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4900 assert_eq!(route.paths.len(), 1);
4901 assert_eq!(route.paths[0].len(), 3);
4903 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4904 assert_eq!(route.paths[0][0].short_channel_id, 6);
4905 assert_eq!(route.paths[0][0].fee_msat, 100);
4906 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4907 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4908 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4910 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4911 assert_eq!(route.paths[0][1].short_channel_id, 5);
4912 assert_eq!(route.paths[0][1].fee_msat, 0);
4913 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4914 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4915 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4917 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4918 assert_eq!(route.paths[0][2].short_channel_id, 1);
4919 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4920 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4921 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4922 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4928 fn exact_fee_liquidity_limit() {
4929 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4930 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4931 // we calculated fees on a higher value, resulting in us ignoring such paths.
4932 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4933 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4934 let scorer = test_utils::TestScorer::with_penalty(0);
4935 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4936 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4937 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4939 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4941 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4942 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4943 short_channel_id: 2,
4946 cltv_expiry_delta: 0,
4947 htlc_minimum_msat: 0,
4948 htlc_maximum_msat: OptionalField::Present(85_000),
4950 fee_proportional_millionths: 0,
4951 excess_data: Vec::new()
4954 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4955 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4956 short_channel_id: 12,
4959 cltv_expiry_delta: (4 << 4) | 1,
4960 htlc_minimum_msat: 0,
4961 htlc_maximum_msat: OptionalField::Present(270_000),
4963 fee_proportional_millionths: 1000000,
4964 excess_data: Vec::new()
4968 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4969 // 200% fee charged channel 13 in the 1-to-2 direction.
4970 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4971 assert_eq!(route.paths.len(), 1);
4972 assert_eq!(route.paths[0].len(), 2);
4974 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4975 assert_eq!(route.paths[0][0].short_channel_id, 12);
4976 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4977 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4978 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4979 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4981 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4982 assert_eq!(route.paths[0][1].short_channel_id, 13);
4983 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4984 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4985 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4986 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4991 fn htlc_max_reduction_below_min() {
4992 // Test that if, while walking the graph, we reduce the value being sent to meet an
4993 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4994 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4995 // resulting in us thinking there is no possible path, even if other paths exist.
4996 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4997 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4998 let scorer = test_utils::TestScorer::with_penalty(0);
4999 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5000 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5001 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
5003 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
5004 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
5005 // then try to send 90_000.
5006 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
5007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5008 short_channel_id: 2,
5011 cltv_expiry_delta: 0,
5012 htlc_minimum_msat: 0,
5013 htlc_maximum_msat: OptionalField::Present(80_000),
5015 fee_proportional_millionths: 0,
5016 excess_data: Vec::new()
5018 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5019 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5020 short_channel_id: 4,
5023 cltv_expiry_delta: (4 << 4) | 1,
5024 htlc_minimum_msat: 90_000,
5025 htlc_maximum_msat: OptionalField::Absent,
5027 fee_proportional_millionths: 0,
5028 excess_data: Vec::new()
5032 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
5033 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
5034 // expensive) channels 12-13 path.
5035 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5036 assert_eq!(route.paths.len(), 1);
5037 assert_eq!(route.paths[0].len(), 2);
5039 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
5040 assert_eq!(route.paths[0][0].short_channel_id, 12);
5041 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
5042 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
5043 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
5044 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
5046 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
5047 assert_eq!(route.paths[0][1].short_channel_id, 13);
5048 assert_eq!(route.paths[0][1].fee_msat, 90_000);
5049 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
5050 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
5051 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
5056 fn multiple_direct_first_hops() {
5057 // Previously we'd only ever considered one first hop path per counterparty.
5058 // However, as we don't restrict users to one channel per peer, we really need to support
5059 // looking at all first hop paths.
5060 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
5061 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
5062 // route over multiple channels with the same first hop.
5063 let secp_ctx = Secp256k1::new();
5064 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5065 let logger = Arc::new(test_utils::TestLogger::new());
5066 let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
5067 let scorer = test_utils::TestScorer::with_penalty(0);
5068 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
5069 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5070 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5073 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5074 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
5075 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
5076 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5077 assert_eq!(route.paths.len(), 1);
5078 assert_eq!(route.paths[0].len(), 1);
5080 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5081 assert_eq!(route.paths[0][0].short_channel_id, 3);
5082 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5085 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5086 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
5087 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
5088 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5089 assert_eq!(route.paths.len(), 2);
5090 assert_eq!(route.paths[0].len(), 1);
5091 assert_eq!(route.paths[1].len(), 1);
5093 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5094 assert_eq!(route.paths[0][0].short_channel_id, 3);
5095 assert_eq!(route.paths[0][0].fee_msat, 50_000);
5097 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
5098 assert_eq!(route.paths[1][0].short_channel_id, 2);
5099 assert_eq!(route.paths[1][0].fee_msat, 50_000);
5103 // If we have a bunch of outbound channels to the same node, where most are not
5104 // sufficient to pay the full payment, but one is, we should default to just using the
5105 // one single channel that has sufficient balance, avoiding MPP.
5107 // If we have several options above the 3xpayment value threshold, we should pick the
5108 // smallest of them, avoiding further fragmenting our available outbound balance to
5110 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5111 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
5112 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
5113 &get_channel_details(Some(5), nodes[0], InitFeatures::known(), 50_000),
5114 &get_channel_details(Some(6), nodes[0], InitFeatures::known(), 300_000),
5115 &get_channel_details(Some(7), nodes[0], InitFeatures::known(), 50_000),
5116 &get_channel_details(Some(8), nodes[0], InitFeatures::known(), 50_000),
5117 &get_channel_details(Some(9), nodes[0], InitFeatures::known(), 50_000),
5118 &get_channel_details(Some(4), nodes[0], InitFeatures::known(), 1_000_000),
5119 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5120 assert_eq!(route.paths.len(), 1);
5121 assert_eq!(route.paths[0].len(), 1);
5123 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5124 assert_eq!(route.paths[0][0].short_channel_id, 6);
5125 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5130 fn prefers_shorter_route_with_higher_fees() {
5131 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5132 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5133 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5135 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5136 let scorer = test_utils::TestScorer::with_penalty(0);
5137 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5138 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5139 let route = get_route(
5140 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5141 Arc::clone(&logger), &scorer, &random_seed_bytes
5143 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5145 assert_eq!(route.get_total_fees(), 100);
5146 assert_eq!(route.get_total_amount(), 100);
5147 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5149 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5150 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5151 let scorer = test_utils::TestScorer::with_penalty(100);
5152 let route = get_route(
5153 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5154 Arc::clone(&logger), &scorer, &random_seed_bytes
5156 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5158 assert_eq!(route.get_total_fees(), 300);
5159 assert_eq!(route.get_total_amount(), 100);
5160 assert_eq!(path, vec![2, 4, 7, 10]);
5163 struct BadChannelScorer {
5164 short_channel_id: u64,
5168 impl Writeable for BadChannelScorer {
5169 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5171 impl Score for BadChannelScorer {
5172 fn channel_penalty_msat(&self, short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId) -> u64 {
5173 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5176 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5177 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5180 struct BadNodeScorer {
5185 impl Writeable for BadNodeScorer {
5186 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5189 impl Score for BadNodeScorer {
5190 fn channel_penalty_msat(&self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, target: &NodeId) -> u64 {
5191 if *target == self.node_id { u64::max_value() } else { 0 }
5194 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5195 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5199 fn avoids_routing_through_bad_channels_and_nodes() {
5200 let (secp_ctx, network, _, _, logger) = build_graph();
5201 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5202 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5203 let network_graph = network.read_only();
5205 // A path to nodes[6] exists when no penalties are applied to any channel.
5206 let scorer = test_utils::TestScorer::with_penalty(0);
5207 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5208 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5209 let route = get_route(
5210 &our_id, &payment_params, &network_graph, None, 100, 42,
5211 Arc::clone(&logger), &scorer, &random_seed_bytes
5213 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5215 assert_eq!(route.get_total_fees(), 100);
5216 assert_eq!(route.get_total_amount(), 100);
5217 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5219 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5220 let scorer = BadChannelScorer { short_channel_id: 6 };
5221 let route = get_route(
5222 &our_id, &payment_params, &network_graph, None, 100, 42,
5223 Arc::clone(&logger), &scorer, &random_seed_bytes
5225 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5227 assert_eq!(route.get_total_fees(), 300);
5228 assert_eq!(route.get_total_amount(), 100);
5229 assert_eq!(path, vec![2, 4, 7, 10]);
5231 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5232 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5234 &our_id, &payment_params, &network_graph, None, 100, 42,
5235 Arc::clone(&logger), &scorer, &random_seed_bytes
5237 Err(LightningError { err, .. } ) => {
5238 assert_eq!(err, "Failed to find a path to the given destination");
5240 Ok(_) => panic!("Expected error"),
5245 fn total_fees_single_path() {
5249 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5250 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5251 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5254 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5255 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5256 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5259 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5260 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5261 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5264 payment_params: None,
5267 assert_eq!(route.get_total_fees(), 250);
5268 assert_eq!(route.get_total_amount(), 225);
5272 fn total_fees_multi_path() {
5276 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5277 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5278 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5281 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5282 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5283 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5287 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5288 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5289 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5292 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5293 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5294 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5297 payment_params: None,
5300 assert_eq!(route.get_total_fees(), 200);
5301 assert_eq!(route.get_total_amount(), 300);
5305 fn total_empty_route_no_panic() {
5306 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5307 // would both panic if the route was completely empty. We test to ensure they return 0
5308 // here, even though its somewhat nonsensical as a route.
5309 let route = Route { paths: Vec::new(), payment_params: None };
5311 assert_eq!(route.get_total_fees(), 0);
5312 assert_eq!(route.get_total_amount(), 0);
5316 fn limits_total_cltv_delta() {
5317 let (secp_ctx, network, _, _, logger) = build_graph();
5318 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5319 let network_graph = network.read_only();
5321 let scorer = test_utils::TestScorer::with_penalty(0);
5323 // Make sure that generally there is at least one route available
5324 let feasible_max_total_cltv_delta = 1008;
5325 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5326 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5327 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5328 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5329 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5330 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5331 assert_ne!(path.len(), 0);
5333 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5334 let fail_max_total_cltv_delta = 23;
5335 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5336 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5337 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5339 Err(LightningError { err, .. } ) => {
5340 assert_eq!(err, "Failed to find a path to the given destination");
5342 Ok(_) => panic!("Expected error"),
5347 fn limits_path_length() {
5348 let (secp_ctx, network, _, _, logger) = build_line_graph();
5349 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5350 let network_graph = network.read_only();
5352 let scorer = test_utils::TestScorer::with_penalty(0);
5353 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5354 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5356 // First check we can actually create a long route on this graph.
5357 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5358 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5359 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5360 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5361 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5363 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5364 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5365 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5366 Arc::clone(&logger), &scorer, &random_seed_bytes)
5368 Err(LightningError { err, .. } ) => {
5369 assert_eq!(err, "Failed to find a path to the given destination");
5371 Ok(_) => panic!("Expected error"),
5376 fn adds_and_limits_cltv_offset() {
5377 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5378 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5380 let scorer = test_utils::TestScorer::with_penalty(0);
5382 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5383 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5384 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5385 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5386 assert_eq!(route.paths.len(), 1);
5388 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5390 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5391 let mut route_default = route.clone();
5392 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5393 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5394 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5395 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5396 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5398 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5399 let mut route_limited = route.clone();
5400 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5401 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5402 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5403 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5404 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5408 fn adds_plausible_cltv_offset() {
5409 let (secp_ctx, network, _, _, logger) = build_graph();
5410 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5411 let network_graph = network.read_only();
5412 let network_nodes = network_graph.nodes();
5413 let network_channels = network_graph.channels();
5414 let scorer = test_utils::TestScorer::with_penalty(0);
5415 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5416 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5417 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5419 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5420 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5421 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5423 let mut path_plausibility = vec![];
5425 for p in route.paths {
5426 // 1. Select random observation point
5427 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5428 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5430 prng.process_in_place(&mut random_bytes);
5431 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5432 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5434 // 2. Calculate what CLTV expiry delta we would observe there
5435 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5437 // 3. Starting from the observation point, find candidate paths
5438 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5439 candidates.push_back((observation_point, vec![]));
5441 let mut found_plausible_candidate = false;
5443 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5444 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5445 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5446 found_plausible_candidate = true;
5447 break 'candidate_loop;
5451 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5452 for channel_id in &cur_node.channels {
5453 if let Some(channel_info) = network_channels.get(&channel_id) {
5454 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5455 if let Some(channel_update_info) = dir_info.direction() {
5456 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5457 if cur_path_cltv_deltas.iter().sum::<u32>()
5458 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5459 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5460 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5461 candidates.push_back((*next_id, new_path_cltv_deltas));
5470 path_plausibility.push(found_plausible_candidate);
5472 assert!(path_plausibility.iter().all(|x| *x));
5475 #[cfg(not(feature = "no-std"))]
5476 pub(super) fn random_init_seed() -> u64 {
5477 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5478 use core::hash::{BuildHasher, Hasher};
5479 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5480 println!("Using seed of {}", seed);
5483 #[cfg(not(feature = "no-std"))]
5484 use util::ser::Readable;
5487 #[cfg(not(feature = "no-std"))]
5488 fn generate_routes() {
5489 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5491 let mut d = match super::test_utils::get_route_file() {
5498 let graph = NetworkGraph::read(&mut d).unwrap();
5499 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5500 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5502 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5503 let mut seed = random_init_seed() as usize;
5504 let nodes = graph.read_only().nodes().clone();
5505 'load_endpoints: for _ in 0..10 {
5507 seed = seed.overflowing_mul(0xdeadbeef).0;
5508 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5509 seed = seed.overflowing_mul(0xdeadbeef).0;
5510 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5511 let payment_params = PaymentParameters::from_node_id(dst);
5512 let amt = seed as u64 % 200_000_000;
5513 let params = ProbabilisticScoringParameters::default();
5514 let logger = test_utils::TestLogger::new();
5515 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5516 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5517 continue 'load_endpoints;
5524 #[cfg(not(feature = "no-std"))]
5525 fn generate_routes_mpp() {
5526 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5528 let mut d = match super::test_utils::get_route_file() {
5535 let graph = NetworkGraph::read(&mut d).unwrap();
5536 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5537 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5539 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5540 let mut seed = random_init_seed() as usize;
5541 let nodes = graph.read_only().nodes().clone();
5542 'load_endpoints: for _ in 0..10 {
5544 seed = seed.overflowing_mul(0xdeadbeef).0;
5545 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5546 seed = seed.overflowing_mul(0xdeadbeef).0;
5547 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5548 let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
5549 let amt = seed as u64 % 200_000_000;
5550 let params = ProbabilisticScoringParameters::default();
5551 let logger = test_utils::TestLogger::new();
5552 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5553 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5554 continue 'load_endpoints;
5561 #[cfg(all(test, not(feature = "no-std")))]
5562 pub(crate) mod test_utils {
5564 /// Tries to open a network graph file, or panics with a URL to fetch it.
5565 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5566 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5567 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5568 .or_else(|_| { // Fall back to guessing based on the binary location
5569 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5570 let mut path = std::env::current_exe().unwrap();
5571 path.pop(); // lightning-...
5573 path.pop(); // debug
5574 path.pop(); // target
5575 path.push("lightning");
5576 path.push("net_graph-2021-05-31.bin");
5577 eprintln!("{}", path.to_str().unwrap());
5580 .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");
5581 #[cfg(require_route_graph_test)]
5582 return Ok(res.unwrap());
5583 #[cfg(not(require_route_graph_test))]
5588 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5591 use bitcoin::hashes::Hash;
5592 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5593 use chain::transaction::OutPoint;
5594 use chain::keysinterface::{KeysManager,KeysInterface};
5595 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
5596 use ln::features::{InitFeatures, InvoiceFeatures};
5597 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters, Scorer};
5598 use util::logger::{Logger, Record};
5599 use util::test_utils::TestLogger;
5603 struct DummyLogger {}
5604 impl Logger for DummyLogger {
5605 fn log(&self, _record: &Record) {}
5608 fn read_network_graph() -> NetworkGraph {
5609 let mut d = test_utils::get_route_file().unwrap();
5610 NetworkGraph::read(&mut d).unwrap()
5613 fn payer_pubkey() -> PublicKey {
5614 let secp_ctx = Secp256k1::new();
5615 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5619 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5621 channel_id: [0; 32],
5622 counterparty: ChannelCounterparty {
5623 features: InitFeatures::known(),
5625 unspendable_punishment_reserve: 0,
5626 forwarding_info: None,
5627 outbound_htlc_minimum_msat: None,
5628 outbound_htlc_maximum_msat: None,
5630 funding_txo: Some(OutPoint {
5631 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5634 short_channel_id: Some(1),
5635 inbound_scid_alias: None,
5636 channel_value_satoshis: 10_000_000,
5638 balance_msat: 10_000_000,
5639 outbound_capacity_msat: 10_000_000,
5640 next_outbound_htlc_limit_msat: 10_000_000,
5641 inbound_capacity_msat: 0,
5642 unspendable_punishment_reserve: None,
5643 confirmations_required: None,
5644 force_close_spend_delay: None,
5646 is_funding_locked: true,
5649 inbound_htlc_minimum_msat: None,
5650 inbound_htlc_maximum_msat: None,
5655 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5656 let network_graph = read_network_graph();
5657 let scorer = FixedPenaltyScorer::with_penalty(0);
5658 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5662 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5663 let network_graph = read_network_graph();
5664 let scorer = FixedPenaltyScorer::with_penalty(0);
5665 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5669 fn generate_routes_with_default_scorer(bench: &mut Bencher) {
5670 let network_graph = read_network_graph();
5671 let scorer = Scorer::default();
5672 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5676 fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
5677 let network_graph = read_network_graph();
5678 let scorer = Scorer::default();
5679 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5683 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5684 let logger = TestLogger::new();
5685 let network_graph = read_network_graph();
5686 let params = ProbabilisticScoringParameters::default();
5687 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5688 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5692 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5693 let logger = TestLogger::new();
5694 let network_graph = read_network_graph();
5695 let params = ProbabilisticScoringParameters::default();
5696 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5697 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5700 fn generate_routes<S: Score>(
5701 bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
5703 let nodes = graph.read_only().nodes().clone();
5704 let payer = payer_pubkey();
5705 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5706 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5708 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5709 let mut routes = Vec::new();
5710 let mut route_endpoints = Vec::new();
5711 let mut seed: usize = 0xdeadbeef;
5712 'load_endpoints: for _ in 0..150 {
5715 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5717 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5718 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5719 let first_hop = first_hop(src);
5720 let amt = seed as u64 % 1_000_000;
5721 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5723 route_endpoints.push((first_hop, params, amt));
5724 continue 'load_endpoints;
5729 // ...and seed the scorer with success and failure data...
5730 for route in routes {
5731 let amount = route.get_total_amount();
5732 if amount < 250_000 {
5733 for path in route.paths {
5734 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5736 } else if amount > 750_000 {
5737 for path in route.paths {
5738 let short_channel_id = path[path.len() / 2].short_channel_id;
5739 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5744 // Because we've changed channel scores, its possible we'll take different routes to the
5745 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5746 // requires a too-high CLTV delta.
5747 route_endpoints.retain(|(first_hop, params, amt)| {
5748 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5750 route_endpoints.truncate(100);
5751 assert_eq!(route_endpoints.len(), 100);
5753 // ...then benchmark finding paths between the nodes we learned.
5756 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5757 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());