1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The top-level routing/network map tracking logic lives here.
12 //! You probably want to create a NetGraphMsgHandler and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
15 use bitcoin::secp256k1::key::PublicKey;
17 use ln::channelmanager::ChannelDetails;
18 use ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
19 use ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
20 use routing::scoring::Score;
21 use routing::network_graph::{DirectedChannelInfoWithUpdate, EffectiveCapacity, NetworkGraph, ReadOnlyNetworkGraph, NodeId, RoutingFees};
22 use util::ser::{Writeable, Readable};
23 use util::logger::{Level, Logger};
24 use util::chacha20::ChaCha20;
28 use alloc::collections::BinaryHeap;
33 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
35 /// The node_id of the node at this hop.
36 pub pubkey: PublicKey,
37 /// The node_announcement features of the node at this hop. For the last hop, these may be
38 /// amended to match the features present in the invoice this node generated.
39 pub node_features: NodeFeatures,
40 /// The channel that should be used from the previous hop to reach this node.
41 pub short_channel_id: u64,
42 /// The channel_announcement features of the channel that should be used from the previous hop
43 /// to reach this node.
44 pub channel_features: ChannelFeatures,
45 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
46 /// For the last hop, this should be the full value of the payment (might be more than
47 /// requested if we had to match htlc_minimum_msat).
49 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
50 /// expected at the destination, in excess of the current block height.
51 pub cltv_expiry_delta: u32,
54 impl_writeable_tlv_based!(RouteHop, {
55 (0, pubkey, required),
56 (2, node_features, required),
57 (4, short_channel_id, required),
58 (6, channel_features, required),
59 (8, fee_msat, required),
60 (10, cltv_expiry_delta, required),
63 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
64 /// it can take multiple paths. Each path is composed of one or more hops through the network.
65 #[derive(Clone, Hash, PartialEq, Eq)]
67 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
68 /// last RouteHop in each path must be the same.
69 /// Each entry represents a list of hops, NOT INCLUDING our own, where the last hop is the
70 /// destination. Thus, this must always be at least length one. While the maximum length of any
71 /// given path is variable, keeping the length of any path to less than 20 should currently
72 /// ensure it is viable.
73 pub paths: Vec<Vec<RouteHop>>,
74 /// The `payment_params` parameter passed to [`find_route`].
75 /// This is used by `ChannelManager` to track information which may be required for retries,
76 /// provided back to you via [`Event::PaymentPathFailed`].
78 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
79 pub payment_params: Option<PaymentParameters>,
82 pub(crate) trait RoutePath {
83 /// Gets the fees for a given path, excluding any excess paid to the recipient.
84 fn get_path_fees(&self) -> u64;
86 impl RoutePath for Vec<RouteHop> {
87 fn get_path_fees(&self) -> u64 {
88 // Do not count last hop of each path since that's the full value of the payment
89 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
90 .iter().map(|hop| &hop.fee_msat)
96 /// Returns the total amount of fees paid on this [`Route`].
98 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
99 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
100 pub fn get_total_fees(&self) -> u64 {
101 self.paths.iter().map(|path| path.get_path_fees()).sum()
104 /// Returns the total amount paid on this [`Route`], excluding the fees.
105 pub fn get_total_amount(&self) -> u64 {
106 return self.paths.iter()
107 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
112 const SERIALIZATION_VERSION: u8 = 1;
113 const MIN_SERIALIZATION_VERSION: u8 = 1;
115 impl Writeable for Route {
116 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
117 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
118 (self.paths.len() as u64).write(writer)?;
119 for hops in self.paths.iter() {
120 (hops.len() as u8).write(writer)?;
121 for hop in hops.iter() {
125 write_tlv_fields!(writer, {
126 (1, self.payment_params, option),
132 impl Readable for Route {
133 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
134 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
135 let path_count: u64 = Readable::read(reader)?;
136 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
137 for _ in 0..path_count {
138 let hop_count: u8 = Readable::read(reader)?;
139 let mut hops = Vec::with_capacity(hop_count as usize);
140 for _ in 0..hop_count {
141 hops.push(Readable::read(reader)?);
145 let mut payment_params = None;
146 read_tlv_fields!(reader, {
147 (1, payment_params, option),
149 Ok(Route { paths, payment_params })
153 /// Parameters needed to find a [`Route`].
155 /// Passed to [`find_route`] and also provided in [`Event::PaymentPathFailed`] for retrying a failed
158 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
159 #[derive(Clone, Debug)]
160 pub struct RouteParameters {
161 /// The parameters of the failed payment path.
162 pub payment_params: PaymentParameters,
164 /// The amount in msats sent on the failed payment path.
165 pub final_value_msat: u64,
167 /// The CLTV on the final hop of the failed payment path.
168 pub final_cltv_expiry_delta: u32,
171 impl_writeable_tlv_based!(RouteParameters, {
172 (0, payment_params, required),
173 (2, final_value_msat, required),
174 (4, final_cltv_expiry_delta, required),
177 /// Maximum total CTLV difference we allow for a full payment path.
178 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
180 /// The median hop CLTV expiry delta currently seen in the network.
181 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
183 /// The recipient of a payment.
184 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
185 pub struct PaymentParameters {
186 /// The node id of the payee.
187 pub payee_pubkey: PublicKey,
189 /// Features supported by the payee.
191 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
192 /// does not contain any features.
194 /// [`for_keysend`]: Self::for_keysend
195 pub features: Option<InvoiceFeatures>,
197 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
198 pub route_hints: Vec<RouteHint>,
200 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
201 pub expiry_time: Option<u64>,
203 /// The maximum total CLTV delta we accept for the route.
204 pub max_total_cltv_expiry_delta: u32,
207 impl_writeable_tlv_based!(PaymentParameters, {
208 (0, payee_pubkey, required),
209 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
210 (2, features, option),
211 (4, route_hints, vec_type),
212 (6, expiry_time, option),
215 impl PaymentParameters {
216 /// Creates a payee with the node id of the given `pubkey`.
217 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
223 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
227 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
228 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
229 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
232 /// Includes the payee's features.
234 /// (C-not exported) since bindings don't support move semantics
235 pub fn with_features(self, features: InvoiceFeatures) -> Self {
236 Self { features: Some(features), ..self }
239 /// Includes hints for routing to the payee.
241 /// (C-not exported) since bindings don't support move semantics
242 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
243 Self { route_hints, ..self }
246 /// Includes a payment expiration in seconds relative to the UNIX epoch.
248 /// (C-not exported) since bindings don't support move semantics
249 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
250 Self { expiry_time: Some(expiry_time), ..self }
253 /// Includes a limit for the total CLTV expiry delta which is considered during routing
255 /// (C-not exported) since bindings don't support move semantics
256 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
257 Self { max_total_cltv_expiry_delta, ..self }
261 /// A list of hops along a payment path terminating with a channel to the recipient.
262 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
263 pub struct RouteHint(pub Vec<RouteHintHop>);
265 impl Writeable for RouteHint {
266 fn write<W: ::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
267 (self.0.len() as u64).write(writer)?;
268 for hop in self.0.iter() {
275 impl Readable for RouteHint {
276 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
277 let hop_count: u64 = Readable::read(reader)?;
278 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
279 for _ in 0..hop_count {
280 hops.push(Readable::read(reader)?);
286 /// A channel descriptor for a hop along a payment path.
287 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
288 pub struct RouteHintHop {
289 /// The node_id of the non-target end of the route
290 pub src_node_id: PublicKey,
291 /// The short_channel_id of this channel
292 pub short_channel_id: u64,
293 /// The fees which must be paid to use this channel
294 pub fees: RoutingFees,
295 /// The difference in CLTV values between this node and the next node.
296 pub cltv_expiry_delta: u16,
297 /// The minimum value, in msat, which must be relayed to the next hop.
298 pub htlc_minimum_msat: Option<u64>,
299 /// The maximum value in msat available for routing with a single HTLC.
300 pub htlc_maximum_msat: Option<u64>,
303 impl_writeable_tlv_based!(RouteHintHop, {
304 (0, src_node_id, required),
305 (1, htlc_minimum_msat, option),
306 (2, short_channel_id, required),
307 (3, htlc_maximum_msat, option),
309 (6, cltv_expiry_delta, required),
312 #[derive(Eq, PartialEq)]
313 struct RouteGraphNode {
315 lowest_fee_to_peer_through_node: u64,
316 lowest_fee_to_node: u64,
317 total_cltv_delta: u32,
318 // The maximum value a yet-to-be-constructed payment path might flow through this node.
319 // This value is upper-bounded by us by:
320 // - how much is needed for a path being constructed
321 // - how much value can channels following this node (up to the destination) can contribute,
322 // considering their capacity and fees
323 value_contribution_msat: u64,
324 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
325 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
326 path_htlc_minimum_msat: u64,
327 /// All penalties incurred from this hop on the way to the destination, as calculated using
329 path_penalty_msat: u64,
332 impl cmp::Ord for RouteGraphNode {
333 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
334 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
335 .saturating_add(other.path_penalty_msat);
336 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
337 .saturating_add(self.path_penalty_msat);
338 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
342 impl cmp::PartialOrd for RouteGraphNode {
343 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
344 Some(self.cmp(other))
348 /// A wrapper around the various hop representations.
350 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
351 #[derive(Clone, Debug)]
352 enum CandidateRouteHop<'a> {
353 /// A hop from the payer, where the outbound liquidity is known.
355 details: &'a ChannelDetails,
357 /// A hop found in the [`NetworkGraph`], where the channel capacity may or may not be known.
359 info: DirectedChannelInfoWithUpdate<'a>,
360 short_channel_id: u64,
362 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
364 hint: &'a RouteHintHop,
368 impl<'a> CandidateRouteHop<'a> {
369 fn short_channel_id(&self) -> u64 {
371 CandidateRouteHop::FirstHop { details } => details.short_channel_id.unwrap(),
372 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
373 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
377 // NOTE: This may alloc memory so avoid calling it in a hot code path.
378 fn features(&self) -> ChannelFeatures {
380 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
381 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
382 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
386 fn cltv_expiry_delta(&self) -> u32 {
388 CandidateRouteHop::FirstHop { .. } => 0,
389 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
390 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
394 fn htlc_minimum_msat(&self) -> u64 {
396 CandidateRouteHop::FirstHop { .. } => 0,
397 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
398 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
402 fn fees(&self) -> RoutingFees {
404 CandidateRouteHop::FirstHop { .. } => RoutingFees {
405 base_msat: 0, proportional_millionths: 0,
407 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
408 CandidateRouteHop::PrivateHop { hint } => hint.fees,
412 fn effective_capacity(&self) -> EffectiveCapacity {
414 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
415 liquidity_msat: details.outbound_capacity_msat,
417 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
418 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
423 /// It's useful to keep track of the hops associated with the fees required to use them,
424 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
425 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
426 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
428 struct PathBuildingHop<'a> {
429 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
430 // is a larger refactor and will require careful performance analysis.
432 candidate: CandidateRouteHop<'a>,
435 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
436 src_lowest_inbound_fees: RoutingFees,
437 /// All the fees paid *after* this channel on the way to the destination
438 next_hops_fee_msat: u64,
439 /// Fee paid for the use of the current channel (see candidate.fees()).
440 /// The value will be actually deducted from the counterparty balance on the previous link.
441 hop_use_fee_msat: u64,
442 /// Used to compare channels when choosing the for routing.
443 /// Includes paying for the use of a hop and the following hops, as well as
444 /// an estimated cost of reaching this hop.
445 /// Might get stale when fees are recomputed. Primarily for internal use.
447 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
448 /// walk and may be invalid thereafter.
449 path_htlc_minimum_msat: u64,
450 /// All penalties incurred from this channel on the way to the destination, as calculated using
452 path_penalty_msat: u64,
453 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
454 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
455 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
456 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
457 /// avoid processing them again.
459 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
460 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
461 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
462 // value_contribution_msat, which requires tracking it here. See comments below where it is
463 // used for more info.
464 value_contribution_msat: u64,
467 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
468 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
469 f.debug_struct("PathBuildingHop")
470 .field("node_id", &self.node_id)
471 .field("short_channel_id", &self.candidate.short_channel_id())
472 .field("total_fee_msat", &self.total_fee_msat)
473 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
474 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
475 .field("total_fee_msat - (next_hops_fee_msat + hop_use_fee_msat)", &(&self.total_fee_msat - (&self.next_hops_fee_msat + &self.hop_use_fee_msat)))
476 .field("path_penalty_msat", &self.path_penalty_msat)
477 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
478 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta())
483 // Instantiated with a list of hops with correct data in them collected during path finding,
484 // an instance of this struct should be further modified only via given methods.
486 struct PaymentPath<'a> {
487 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
490 impl<'a> PaymentPath<'a> {
491 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
492 fn get_value_msat(&self) -> u64 {
493 self.hops.last().unwrap().0.fee_msat
496 fn get_path_penalty_msat(&self) -> u64 {
497 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
500 fn get_total_fee_paid_msat(&self) -> u64 {
501 if self.hops.len() < 1 {
505 // Can't use next_hops_fee_msat because it gets outdated.
506 for (i, (hop, _)) in self.hops.iter().enumerate() {
507 if i != self.hops.len() - 1 {
508 result += hop.fee_msat;
514 fn get_cost_msat(&self) -> u64 {
515 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
518 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
519 // to change fees may result in an inconsistency.
521 // Sometimes we call this function right after constructing a path which is inconsistent in
522 // that it the value being transferred has decreased while we were doing path finding, leading
523 // to the fees being paid not lining up with the actual limits.
525 // Note that this function is not aware of the available_liquidity limit, and thus does not
526 // support increasing the value being transferred.
527 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
528 assert!(value_msat <= self.hops.last().unwrap().0.fee_msat);
530 let mut total_fee_paid_msat = 0 as u64;
531 for i in (0..self.hops.len()).rev() {
532 let last_hop = i == self.hops.len() - 1;
534 // For non-last-hop, this value will represent the fees paid on the current hop. It
535 // will consist of the fees for the use of the next hop, and extra fees to match
536 // htlc_minimum_msat of the current channel. Last hop is handled separately.
537 let mut cur_hop_fees_msat = 0;
539 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
542 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
543 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
544 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
545 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
546 // set it too high just to maliciously take more fees by exploiting this
547 // match htlc_minimum_msat logic.
548 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
549 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
550 // Note that there is a risk that *previous hops* (those closer to us, as we go
551 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
553 // This might make us end up with a broken route, although this should be super-rare
554 // in practice, both because of how healthy channels look like, and how we pick
555 // channels in add_entry.
556 // Also, this can't be exploited more heavily than *announce a free path and fail
558 cur_hop_transferred_amount_msat += extra_fees_msat;
559 total_fee_paid_msat += extra_fees_msat;
560 cur_hop_fees_msat += extra_fees_msat;
564 // Final hop is a special case: it usually has just value_msat (by design), but also
565 // it still could overpay for the htlc_minimum_msat.
566 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
568 // Propagate updated fees for the use of the channels to one hop back, where they
569 // will be actually paid (fee_msat). The last hop is handled above separately.
570 cur_hop.fee_msat = cur_hop_fees_msat;
573 // Fee for the use of the current hop which will be deducted on the previous hop.
574 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
575 // this channel is free for us.
577 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
578 cur_hop.hop_use_fee_msat = new_fee;
579 total_fee_paid_msat += new_fee;
581 // It should not be possible because this function is called only to reduce the
582 // value. In that case, compute_fee was already called with the same fees for
583 // larger amount and there was no overflow.
591 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
592 let proportional_fee_millions =
593 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
594 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
595 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
599 // This function may be (indirectly) called without any verification,
600 // with channel_fees provided by a caller. We should handle it gracefully.
605 /// The default `features` we assume for a node in a route, when no `features` are known about that
608 /// Default features are:
609 /// * variable_length_onion_optional
610 fn default_node_features() -> NodeFeatures {
611 let mut features = NodeFeatures::empty();
612 features.set_variable_length_onion_optional();
616 /// Finds a route from us (payer) to the given target node (payee).
618 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
619 /// Without this, MPP will only be used if the payee's features are available in the network graph.
621 /// Private routing paths between a public node and the target may be included in `params.payee`.
623 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
624 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of our local
625 /// channels from [`NetworkGraph`] will be ignored, and only those in `first_hops` will be used.
627 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
628 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
629 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
633 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
634 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
639 /// Panics if first_hops contains channels without short_channel_ids;
640 /// [`ChannelManager::list_usable_channels`] will never include such channels.
642 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
643 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
644 pub fn find_route<L: Deref, S: Score>(
645 our_node_pubkey: &PublicKey, route_params: &RouteParameters, network: &NetworkGraph,
646 first_hops: Option<&[&ChannelDetails]>, logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
647 ) -> Result<Route, LightningError>
648 where L::Target: Logger {
649 let network_graph = network.read_only();
651 our_node_pubkey, &route_params.payment_params, &network_graph, first_hops, route_params.final_value_msat,
652 route_params.final_cltv_expiry_delta, logger, scorer, random_seed_bytes
655 add_random_cltv_offset(&mut route, &route_params.payment_params, &network_graph, random_seed_bytes);
658 Err(err) => Err(err),
662 pub(crate) fn get_route<L: Deref, S: Score>(
663 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
664 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
665 logger: L, scorer: &S, random_seed_bytes: &[u8; 32]
666 ) -> Result<Route, LightningError>
667 where L::Target: Logger {
668 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
669 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
671 if payee_node_id == our_node_id {
672 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
675 if final_value_msat > MAX_VALUE_MSAT {
676 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
679 if final_value_msat == 0 {
680 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
683 for route in payment_params.route_hints.iter() {
684 for hop in &route.0 {
685 if hop.src_node_id == payment_params.payee_pubkey {
686 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
690 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
691 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});
694 // The general routing idea is the following:
695 // 1. Fill first/last hops communicated by the caller.
696 // 2. Attempt to construct a path from payer to payee for transferring
697 // any ~sufficient (described later) value.
698 // If succeed, remember which channels were used and how much liquidity they have available,
699 // so that future paths don't rely on the same liquidity.
700 // 3. Proceed to the next step if:
701 // - we hit the recommended target value;
702 // - OR if we could not construct a new path. Any next attempt will fail too.
703 // Otherwise, repeat step 2.
704 // 4. See if we managed to collect paths which aggregately are able to transfer target value
705 // (not recommended value).
706 // 5. If yes, proceed. If not, fail routing.
707 // 6. Randomly combine paths into routes having enough to fulfill the payment. (TODO: knapsack)
708 // 7. Of all the found paths, select only those with the lowest total fee.
709 // 8. The last path in every selected route is likely to be more than we need.
710 // Reduce its value-to-transfer and recompute fees.
711 // 9. Choose the best route by the lowest total fee.
713 // As for the actual search algorithm,
714 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
715 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
717 // We are not a faithful Dijkstra's implementation because we can change values which impact
718 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
719 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
720 // the value we are currently attempting to send over a path, we simply reduce the value being
721 // sent along the path for any hops after that channel. This may imply that later fees (which
722 // we've already tabulated) are lower because a smaller value is passing through the channels
723 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
724 // channels which were selected earlier (and which may still be used for other paths without a
725 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
728 // One potentially problematic case for this algorithm would be if there are many
729 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
730 // graph walking), we may never find a path which is not liquidity-limited and has lower
731 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
732 // Because we only consider paths with at least 5% of the total value being sent, the damage
733 // from such a case should be limited, however this could be further reduced in the future by
734 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
735 // limits for the purposes of fee calculation.
737 // Alternatively, we could store more detailed path information in the heap (targets, below)
738 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
739 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
740 // and practically (as we would need to store dynamically-allocated path information in heap
741 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
742 // results of such an algorithm would likely be biased towards lower-value paths.
744 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
745 // outside of our current search value, running a path search more times to gather candidate
746 // paths at different values. While this may be acceptable, further path searches may increase
747 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
748 // graph for candidate paths, calculating the maximum value which can realistically be sent at
749 // the same time, remaining generic across different payment values.
751 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
752 // to use as the A* heuristic beyond just the cost to get one node further than the current
755 let network_channels = network_graph.channels();
756 let network_nodes = network_graph.nodes();
758 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
759 // it. If the payee supports it they're supposed to include it in the invoice, so that should
761 let allow_mpp = if let Some(features) = &payment_params.features {
762 features.supports_basic_mpp()
763 } else if let Some(node) = network_nodes.get(&payee_node_id) {
764 if let Some(node_info) = node.announcement_info.as_ref() {
765 node_info.features.supports_basic_mpp()
768 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
769 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
770 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
773 // Prepare the data we'll use for payee-to-payer search by
774 // inserting first hops suggested by the caller as targets.
775 // Our search will then attempt to reach them while traversing from the payee node.
776 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
777 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
778 if let Some(hops) = first_hops {
780 if chan.short_channel_id.is_none() {
781 panic!("first_hops should be filled in with usable channels, not pending ones");
783 if chan.counterparty.node_id == *our_node_pubkey {
784 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
787 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
788 .or_insert(Vec::new())
791 if first_hop_targets.is_empty() {
792 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
796 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
797 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
798 // adding duplicate entries when we find a better path to a given node.
799 let mut targets = BinaryHeap::new();
801 // Map from node_id to information about the best current path to that node, including feerate
803 let mut dist = HashMap::with_capacity(network_nodes.len());
805 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
806 // indicating that we may wish to try again with a higher value, potentially paying to meet an
807 // htlc_minimum with extra fees while still finding a cheaper path.
808 let mut hit_minimum_limit;
810 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
811 // We start with a path_value of the exact amount we want, and if that generates a route we may
812 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
813 // amount we want in total across paths, selecting the best subset at the end.
814 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
815 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
816 let mut path_value_msat = final_value_msat;
818 // We don't want multiple paths (as per MPP) share liquidity of the same channels.
819 // This map allows paths to be aware of the channel use by other paths in the same call.
820 // This would help to make a better path finding decisions and not "overbook" channels.
821 // It is unaware of the directions (except for `outbound_capacity_msat` in `first_hops`).
822 let mut bookkept_channels_liquidity_available_msat = HashMap::with_capacity(network_nodes.len());
824 // Keeping track of how much value we already collected across other paths. Helps to decide:
825 // - how much a new path should be transferring (upper bound);
826 // - whether a channel should be disregarded because
827 // it's available liquidity is too small comparing to how much more we need to collect;
828 // - when we want to stop looking for new paths.
829 let mut already_collected_value_msat = 0;
831 for (_, channels) in first_hop_targets.iter_mut() {
832 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
835 // First, if channels are below `recommended_value_msat`, sort them in descending order,
836 // preferring larger channels to avoid splitting the payment into more MPP parts than is
839 // Second, because simply always sorting in descending order would always use our largest
840 // available outbound capacity, needlessly fragmenting our available channel capacities,
841 // sort channels above `recommended_value_msat` in ascending order, preferring channels
842 // which have enough, but not too much, capacity for the payment.
843 channels.sort_unstable_by(|chan_a, chan_b| {
844 if chan_b.outbound_capacity_msat < recommended_value_msat || chan_a.outbound_capacity_msat < recommended_value_msat {
845 // Sort in descending order
846 chan_b.outbound_capacity_msat.cmp(&chan_a.outbound_capacity_msat)
848 // Sort in ascending order
849 chan_a.outbound_capacity_msat.cmp(&chan_b.outbound_capacity_msat)
854 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
856 macro_rules! add_entry {
857 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
858 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
859 // since that value has to be transferred over this channel.
860 // Returns whether this channel caused an update to `targets`.
861 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
862 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
863 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => { {
864 // We "return" whether we updated the path at the end, via this:
865 let mut did_add_update_path_to_src_node = false;
866 // Channels to self should not be used. This is more of belt-and-suspenders, because in
867 // practice these cases should be caught earlier:
868 // - for regular channels at channel announcement (TODO)
869 // - for first and last hops early in get_route
870 if $src_node_id != $dest_node_id {
871 let short_channel_id = $candidate.short_channel_id();
872 let available_liquidity_msat = bookkept_channels_liquidity_available_msat
873 .entry(short_channel_id)
874 .or_insert_with(|| $candidate.effective_capacity().as_msat());
876 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
877 // It may be misleading because we might later choose to reduce the value transferred
878 // over these channels, and the channel which was insufficient might become sufficient.
879 // Worst case: we drop a good channel here because it can't cover the high following
880 // fees caused by one expensive channel, but then this channel could have been used
881 // if the amount being transferred over this path is lower.
882 // We do this for now, but this is a subject for removal.
883 if let Some(available_value_contribution_msat) = available_liquidity_msat.checked_sub($next_hops_fee_msat) {
885 // Routing Fragmentation Mitigation heuristic:
887 // Routing fragmentation across many payment paths increases the overall routing
888 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
889 // Taking too many smaller paths also increases the chance of payment failure.
890 // Thus to avoid this effect, we require from our collected links to provide
891 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
893 // This requirement is currently 5% of the remaining-to-be-collected value.
894 // This means as we successfully advance in our collection,
895 // the absolute liquidity contribution is lowered,
896 // thus increasing the number of potential channels to be selected.
898 // Derive the minimal liquidity contribution with a ratio of 20 (5%, rounded up)
899 // or 100% if we're not allowed to do multipath payments.
900 let minimal_value_contribution_msat: u64 = if allow_mpp {
901 (recommended_value_msat - already_collected_value_msat + 19) / 20
905 // Verify the liquidity offered by this channel complies to the minimal contribution.
906 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
908 // Do not consider candidates that exceed the maximum total cltv expiry limit.
909 // In order to already account for some of the privacy enhancing random CLTV
910 // expiry delta offset we add on top later, we subtract a rough estimate
911 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
912 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
913 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
914 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
915 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
916 .saturating_add($candidate.cltv_expiry_delta());
917 let doesnt_exceed_cltv_delta_limit = hop_total_cltv_delta <= max_total_cltv_expiry_delta;
919 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
920 // Includes paying fees for the use of the following channels.
921 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
922 Some(result) => result,
923 // Can't overflow due to how the values were computed right above.
924 None => unreachable!(),
926 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
927 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
928 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
930 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
931 let may_overpay_to_meet_path_minimum_msat =
932 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
933 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
934 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
935 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
937 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
938 // bother considering this channel. If retrying with recommended_value_msat may
939 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
940 // around again with a higher amount.
941 if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit && may_overpay_to_meet_path_minimum_msat {
942 hit_minimum_limit = true;
943 } else if contributes_sufficient_value && doesnt_exceed_cltv_delta_limit && over_path_minimum_msat {
944 // Note that low contribution here (limited by available_liquidity_msat)
945 // might violate htlc_minimum_msat on the hops which are next along the
946 // payment path (upstream to the payee). To avoid that, we recompute
947 // path fees knowing the final path contribution after constructing it.
948 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
949 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
950 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
951 .unwrap_or_else(|| u64::max_value());
952 let hm_entry = dist.entry($src_node_id);
953 let old_entry = hm_entry.or_insert_with(|| {
954 // If there was previously no known way to access the source node
955 // (recall it goes payee-to-payer) of short_channel_id, first add a
956 // semi-dummy record just to compute the fees to reach the source node.
957 // This will affect our decision on selecting short_channel_id
958 // as a way to reach the $dest_node_id.
959 let mut fee_base_msat = 0;
960 let mut fee_proportional_millionths = 0;
961 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
962 fee_base_msat = fees.base_msat;
963 fee_proportional_millionths = fees.proportional_millionths;
966 node_id: $dest_node_id.clone(),
967 candidate: $candidate.clone(),
969 src_lowest_inbound_fees: RoutingFees {
970 base_msat: fee_base_msat,
971 proportional_millionths: fee_proportional_millionths,
973 next_hops_fee_msat: u64::max_value(),
974 hop_use_fee_msat: u64::max_value(),
975 total_fee_msat: u64::max_value(),
976 path_htlc_minimum_msat,
977 path_penalty_msat: u64::max_value(),
978 was_processed: false,
979 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
980 value_contribution_msat,
984 #[allow(unused_mut)] // We only use the mut in cfg(test)
985 let mut should_process = !old_entry.was_processed;
986 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
988 // In test/fuzzing builds, we do extra checks to make sure the skipping
989 // of already-seen nodes only happens in cases we expect (see below).
990 if !should_process { should_process = true; }
994 let mut hop_use_fee_msat = 0;
995 let mut total_fee_msat = $next_hops_fee_msat;
997 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
998 // will have the same effective-fee
999 if $src_node_id != our_node_id {
1000 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1001 // max_value means we'll always fail
1002 // the old_entry.total_fee_msat > total_fee_msat check
1003 None => total_fee_msat = u64::max_value(),
1005 hop_use_fee_msat = fee_msat;
1006 total_fee_msat += hop_use_fee_msat;
1007 // When calculating the lowest inbound fees to a node, we
1008 // calculate fees here not based on the actual value we think
1009 // will flow over this channel, but on the minimum value that
1010 // we'll accept flowing over it. The minimum accepted value
1011 // is a constant through each path collection run, ensuring
1012 // consistent basis. Otherwise we may later find a
1013 // different path to the source node that is more expensive,
1014 // but which we consider to be cheaper because we are capacity
1015 // constrained and the relative fee becomes lower.
1016 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1017 .map(|a| a.checked_add(total_fee_msat)) {
1022 total_fee_msat = u64::max_value();
1029 let path_penalty_msat = $next_hops_path_penalty_msat.saturating_add(
1030 scorer.channel_penalty_msat(short_channel_id, amount_to_transfer_over_msat,
1031 *available_liquidity_msat, &$src_node_id, &$dest_node_id));
1032 let new_graph_node = RouteGraphNode {
1033 node_id: $src_node_id,
1034 lowest_fee_to_peer_through_node: total_fee_msat,
1035 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1036 total_cltv_delta: hop_total_cltv_delta,
1037 value_contribution_msat: value_contribution_msat,
1038 path_htlc_minimum_msat,
1042 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1043 // if this way is cheaper than the already known
1044 // (considering the cost to "reach" this channel from the route destination,
1045 // the cost of using this channel,
1046 // and the cost of routing to the source node of this channel).
1047 // Also, consider that htlc_minimum_msat_difference, because we might end up
1048 // paying it. Consider the following exploit:
1049 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1050 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1051 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1052 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1054 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1055 // but it may require additional tracking - we don't want to double-count
1056 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1057 // can't use something that may decrease on future hops.
1058 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1059 .saturating_add(old_entry.path_penalty_msat);
1060 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1061 .saturating_add(path_penalty_msat);
1063 if !old_entry.was_processed && new_cost < old_cost {
1064 targets.push(new_graph_node);
1065 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1066 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1067 old_entry.total_fee_msat = total_fee_msat;
1068 old_entry.node_id = $dest_node_id.clone();
1069 old_entry.candidate = $candidate.clone();
1070 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1071 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1072 old_entry.path_penalty_msat = path_penalty_msat;
1073 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1075 old_entry.value_contribution_msat = value_contribution_msat;
1077 did_add_update_path_to_src_node = true;
1078 } else if old_entry.was_processed && new_cost < old_cost {
1079 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1081 // If we're skipping processing a node which was previously
1082 // processed even though we found another path to it with a
1083 // cheaper fee, check that it was because the second path we
1084 // found (which we are processing now) has a lower value
1085 // contribution due to an HTLC minimum limit.
1087 // e.g. take a graph with two paths from node 1 to node 2, one
1088 // through channel A, and one through channel B. Channel A and
1089 // B are both in the to-process heap, with their scores set by
1090 // a higher htlc_minimum than fee.
1091 // Channel A is processed first, and the channels onwards from
1092 // node 1 are added to the to-process heap. Thereafter, we pop
1093 // Channel B off of the heap, note that it has a much more
1094 // restrictive htlc_maximum_msat, and recalculate the fees for
1095 // all of node 1's channels using the new, reduced, amount.
1097 // This would be bogus - we'd be selecting a higher-fee path
1098 // with a lower htlc_maximum_msat instead of the one we'd
1099 // already decided to use.
1100 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1102 value_contribution_msat + path_penalty_msat <
1103 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1111 did_add_update_path_to_src_node
1115 let default_node_features = default_node_features();
1117 // Find ways (channels with destination) to reach a given node and store them
1118 // in the corresponding data structures (routing graph etc).
1119 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1120 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1121 // This data can later be helpful to optimize routing (pay lower fees).
1122 macro_rules! add_entries_to_cheapest_to_target_node {
1123 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr ) => {
1124 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1125 let was_processed = elem.was_processed;
1126 elem.was_processed = true;
1129 // Entries are added to dist in add_entry!() when there is a channel from a node.
1130 // Because there are no channels from payee, it will not have a dist entry at this point.
1131 // If we're processing any other node, it is always be the result of a channel from it.
1132 assert_eq!($node_id, payee_node_id);
1137 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1138 for details in first_channels {
1139 let candidate = CandidateRouteHop::FirstHop { details };
1140 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1144 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1147 &default_node_features
1150 if !features.requires_unknown_bits() {
1151 for chan_id in $node.channels.iter() {
1152 let chan = network_channels.get(chan_id).unwrap();
1153 if !chan.features.requires_unknown_bits() {
1154 let (directed_channel, source) =
1155 chan.as_directed_to(&$node_id).expect("inconsistent NetworkGraph");
1156 if first_hops.is_none() || *source != our_node_id {
1157 if let Some(direction) = directed_channel.direction() {
1158 if direction.enabled {
1159 let candidate = CandidateRouteHop::PublicHop {
1160 info: directed_channel.with_update().unwrap(),
1161 short_channel_id: *chan_id,
1163 add_entry!(candidate, *source, $node_id, $fee_to_target_msat, $next_hops_value_contribution, $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat, $next_hops_cltv_delta);
1174 let mut payment_paths = Vec::<PaymentPath>::new();
1176 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1177 'paths_collection: loop {
1178 // For every new path, start from scratch, except
1179 // bookkept_channels_liquidity_available_msat, which will improve
1180 // the further iterations of path finding. Also don't erase first_hop_targets.
1183 hit_minimum_limit = false;
1185 // If first hop is a private channel and the only way to reach the payee, this is the only
1186 // place where it could be added.
1187 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1188 for details in first_channels {
1189 let candidate = CandidateRouteHop::FirstHop { details };
1190 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1191 log_trace!(logger, "{} direct route to payee via SCID {}", if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1195 // Add the payee as a target, so that the payee-to-payer
1196 // search algorithm knows what to start with.
1197 match network_nodes.get(&payee_node_id) {
1198 // The payee is not in our network graph, so nothing to add here.
1199 // There is still a chance of reaching them via last_hops though,
1200 // so don't yet fail the payment here.
1201 // If not, targets.pop() will not even let us enter the loop in step 2.
1204 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0);
1209 // If a caller provided us with last hops, add them to routing targets. Since this happens
1210 // earlier than general path finding, they will be somewhat prioritized, although currently
1211 // it matters only if the fees are exactly the same.
1212 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1213 let first_hop_in_route = &(route.0)[0];
1214 let have_hop_src_in_graph =
1215 // Only add the hops in this route to our candidate set if either
1216 // we have a direct channel to the first hop or the first hop is
1217 // in the regular network graph.
1218 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1219 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1220 if have_hop_src_in_graph {
1221 // We start building the path from reverse, i.e., from payee
1222 // to the first RouteHintHop in the path.
1223 let hop_iter = route.0.iter().rev();
1224 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1225 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1226 let mut hop_used = true;
1227 let mut aggregate_next_hops_fee_msat: u64 = 0;
1228 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1229 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1230 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1232 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1233 let source = NodeId::from_pubkey(&hop.src_node_id);
1234 let target = NodeId::from_pubkey(&prev_hop_id);
1235 let candidate = network_channels
1236 .get(&hop.short_channel_id)
1237 .and_then(|channel| channel.as_directed_to(&target))
1238 .and_then(|(channel, _)| channel.with_update())
1239 .map(|info| CandidateRouteHop::PublicHop {
1241 short_channel_id: hop.short_channel_id,
1243 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1244 let capacity_msat = candidate.effective_capacity().as_msat();
1245 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1246 .saturating_add(scorer.channel_penalty_msat(hop.short_channel_id, final_value_msat, capacity_msat, &source, &target));
1248 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1249 .saturating_add(hop.cltv_expiry_delta as u32);
1251 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta) {
1252 // If this hop was not used then there is no use checking the preceding hops
1253 // in the RouteHint. We can break by just searching for a direct channel between
1254 // last checked hop and first_hop_targets
1258 // Searching for a direct channel between last checked hop and first_hop_targets
1259 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1260 for details in first_channels {
1261 let candidate = CandidateRouteHop::FirstHop { details };
1262 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id), aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta);
1270 // In the next values of the iterator, the aggregate fees already reflects
1271 // the sum of value sent from payer (final_value_msat) and routing fees
1272 // for the last node in the RouteHint. We need to just add the fees to
1273 // route through the current node so that the preceeding node (next iteration)
1275 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1276 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1277 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1279 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1280 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1281 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1282 .checked_add(hop_htlc_minimum_msat_inc);
1283 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1285 if idx == route.0.len() - 1 {
1286 // The last hop in this iterator is the first hop in
1287 // overall RouteHint.
1288 // If this hop connects to a node with which we have a direct channel,
1289 // ignore the network graph and, if the last hop was added, add our
1290 // direct channel to the candidate set.
1292 // Note that we *must* check if the last hop was added as `add_entry`
1293 // always assumes that the third argument is a node to which we have a
1295 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1296 for details in first_channels {
1297 let candidate = CandidateRouteHop::FirstHop { details };
1298 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&hop.src_node_id), aggregate_next_hops_fee_msat, path_value_msat, aggregate_next_hops_path_htlc_minimum_msat, aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta);
1306 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1308 // At this point, targets are filled with the data from first and
1309 // last hops communicated by the caller, and the payment receiver.
1310 let mut found_new_path = false;
1313 // If this loop terminates due the exhaustion of targets, two situations are possible:
1314 // - not enough outgoing liquidity:
1315 // 0 < already_collected_value_msat < final_value_msat
1316 // - enough outgoing liquidity:
1317 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1318 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1319 // paths_collection will be stopped because found_new_path==false.
1320 // This is not necessarily a routing failure.
1321 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, .. }) = targets.pop() {
1323 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1324 // traversing the graph and arrange the path out of what we found.
1325 if node_id == our_node_id {
1326 let mut new_entry = dist.remove(&our_node_id).unwrap();
1327 let mut ordered_hops = vec!((new_entry.clone(), default_node_features.clone()));
1330 let mut features_set = false;
1331 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1332 for details in first_channels {
1333 if details.short_channel_id.unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1334 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1335 features_set = true;
1341 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1342 if let Some(node_info) = node.announcement_info.as_ref() {
1343 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1345 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1348 // We can fill in features for everything except hops which were
1349 // provided via the invoice we're paying. We could guess based on the
1350 // recipient's features but for now we simply avoid guessing at all.
1354 // Means we succesfully traversed from the payer to the payee, now
1355 // save this path for the payment route. Also, update the liquidity
1356 // remaining on the used hops, so that we take them into account
1357 // while looking for more paths.
1358 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1362 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1363 Some(payment_hop) => payment_hop,
1364 // We can't arrive at None because, if we ever add an entry to targets,
1365 // we also fill in the entry in dist (see add_entry!).
1366 None => unreachable!(),
1368 // We "propagate" the fees one hop backward (topologically) here,
1369 // so that fees paid for a HTLC forwarding on the current channel are
1370 // associated with the previous channel (where they will be subtracted).
1371 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1372 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1374 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1375 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1377 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1378 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1380 let mut payment_path = PaymentPath {hops: ordered_hops};
1382 // We could have possibly constructed a slightly inconsistent path: since we reduce
1383 // value being transferred along the way, we could have violated htlc_minimum_msat
1384 // on some channels we already passed (assuming dest->source direction). Here, we
1385 // recompute the fees again, so that if that's the case, we match the currently
1386 // underpaid htlc_minimum_msat with fees.
1387 payment_path.update_value_and_recompute_fees(cmp::min(value_contribution_msat, final_value_msat));
1389 // Since a path allows to transfer as much value as
1390 // the smallest channel it has ("bottleneck"), we should recompute
1391 // the fees so sender HTLC don't overpay fees when traversing
1392 // larger channels than the bottleneck. This may happen because
1393 // when we were selecting those channels we were not aware how much value
1394 // this path will transfer, and the relative fee for them
1395 // might have been computed considering a larger value.
1396 // Remember that we used these channels so that we don't rely
1397 // on the same liquidity in future paths.
1398 let mut prevented_redundant_path_selection = false;
1399 for (payment_hop, _) in payment_path.hops.iter() {
1400 let channel_liquidity_available_msat = bookkept_channels_liquidity_available_msat.get_mut(&payment_hop.candidate.short_channel_id()).unwrap();
1401 let mut spent_on_hop_msat = value_contribution_msat;
1402 let next_hops_fee_msat = payment_hop.next_hops_fee_msat;
1403 spent_on_hop_msat += next_hops_fee_msat;
1404 if spent_on_hop_msat == *channel_liquidity_available_msat {
1405 // If this path used all of this channel's available liquidity, we know
1406 // this path will not be selected again in the next loop iteration.
1407 prevented_redundant_path_selection = true;
1409 *channel_liquidity_available_msat -= spent_on_hop_msat;
1411 if !prevented_redundant_path_selection {
1412 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1413 // we'll probably end up picking the same path again on the next iteration.
1414 // Decrease the available liquidity of a hop in the middle of the path.
1415 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1416 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1417 let victim_liquidity = bookkept_channels_liquidity_available_msat.get_mut(&victim_scid).unwrap();
1418 *victim_liquidity = 0;
1421 // Track the total amount all our collected paths allow to send so that we:
1422 // - know when to stop looking for more paths
1423 // - know which of the hops are useless considering how much more sats we need
1424 // (contributes_sufficient_value)
1425 already_collected_value_msat += value_contribution_msat;
1427 payment_paths.push(payment_path);
1428 found_new_path = true;
1429 break 'path_construction;
1432 // If we found a path back to the payee, we shouldn't try to process it again. This is
1433 // the equivalent of the `elem.was_processed` check in
1434 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1435 if node_id == payee_node_id { continue 'path_construction; }
1437 // Otherwise, since the current target node is not us,
1438 // keep "unrolling" the payment graph from payee to payer by
1439 // finding a way to reach the current target from the payer side.
1440 match network_nodes.get(&node_id) {
1443 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node, value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, total_cltv_delta);
1449 // If we don't support MPP, no use trying to gather more value ever.
1450 break 'paths_collection;
1454 // Stop either when the recommended value is reached or if no new path was found in this
1456 // In the latter case, making another path finding attempt won't help,
1457 // because we deterministically terminated the search due to low liquidity.
1458 if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1459 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1460 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1461 break 'paths_collection;
1462 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1463 // Further, if this was our first walk of the graph, and we weren't limited by an
1464 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1465 // limited by an htlc_minimum_msat value, find another path with a higher value,
1466 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1467 // still keeping a lower total fee than this path.
1468 if !hit_minimum_limit {
1469 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1470 break 'paths_collection;
1472 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1473 path_value_msat = recommended_value_msat;
1478 if payment_paths.len() == 0 {
1479 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1482 if already_collected_value_msat < final_value_msat {
1483 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1486 // Sort by total fees and take the best paths.
1487 payment_paths.sort_unstable_by_key(|path| path.get_total_fee_paid_msat());
1488 if payment_paths.len() > 50 {
1489 payment_paths.truncate(50);
1492 // Draw multiple sufficient routes by randomly combining the selected paths.
1493 let mut drawn_routes = Vec::new();
1494 let mut prng = ChaCha20::new(random_seed_bytes, &[0u8; 12]);
1495 let mut random_index_bytes = [0u8; ::core::mem::size_of::<usize>()];
1497 let num_permutations = payment_paths.len();
1498 for _ in 0..num_permutations {
1499 let mut cur_route = Vec::<PaymentPath>::new();
1500 let mut aggregate_route_value_msat = 0;
1503 // Do a Fisher-Yates shuffle to create a random permutation of the payment paths
1504 for cur_index in (1..payment_paths.len()).rev() {
1505 prng.process_in_place(&mut random_index_bytes);
1506 let random_index = usize::from_be_bytes(random_index_bytes).wrapping_rem(cur_index+1);
1507 payment_paths.swap(cur_index, random_index);
1511 for payment_path in &payment_paths {
1512 cur_route.push(payment_path.clone());
1513 aggregate_route_value_msat += payment_path.get_value_msat();
1514 if aggregate_route_value_msat > final_value_msat {
1515 // Last path likely overpaid. Substract it from the most expensive
1516 // (in terms of proportional fee) path in this route and recompute fees.
1517 // This might be not the most economically efficient way, but fewer paths
1518 // also makes routing more reliable.
1519 let mut overpaid_value_msat = aggregate_route_value_msat - final_value_msat;
1521 // First, we drop some expensive low-value paths entirely if possible, since fewer
1522 // paths is better: the payment is less likely to fail. In order to do so, we sort
1523 // by value and fall back to total fees paid, i.e., in case of equal values we
1524 // prefer lower cost paths.
1525 cur_route.sort_unstable_by(|a, b| {
1526 a.get_value_msat().cmp(&b.get_value_msat())
1527 // Reverse ordering for cost, so we drop higher-cost paths first
1528 .then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1531 // We should make sure that at least 1 path left.
1532 let mut paths_left = cur_route.len();
1533 cur_route.retain(|path| {
1534 if paths_left == 1 {
1537 let mut keep = true;
1538 let path_value_msat = path.get_value_msat();
1539 if path_value_msat <= overpaid_value_msat {
1541 overpaid_value_msat -= path_value_msat;
1547 if overpaid_value_msat == 0 {
1551 assert!(cur_route.len() > 0);
1554 // Now, subtract the overpaid value from the most-expensive path.
1555 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1556 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1557 cur_route.sort_unstable_by_key(|path| { path.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>() });
1558 let expensive_payment_path = cur_route.first_mut().unwrap();
1560 // We already dropped all the small value paths above, meaning all the
1561 // remaining paths are larger than remaining overpaid_value_msat.
1562 // Thus, this can't be negative.
1563 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1564 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1568 drawn_routes.push(cur_route);
1572 // Select the best route by lowest total cost.
1573 drawn_routes.sort_unstable_by_key(|paths| paths.iter().map(|path| path.get_cost_msat()).sum::<u64>());
1574 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1575 for payment_path in drawn_routes.first().unwrap() {
1576 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1578 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)})?,
1579 node_features: node_features.clone(),
1580 short_channel_id: payment_hop.candidate.short_channel_id(),
1581 channel_features: payment_hop.candidate.features(),
1582 fee_msat: payment_hop.fee_msat,
1583 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1585 }).collect::<Vec<_>>();
1586 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1587 // applicable for the previous hop.
1588 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1589 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1591 selected_paths.push(path);
1594 if let Some(features) = &payment_params.features {
1595 for path in selected_paths.iter_mut() {
1596 if let Ok(route_hop) = path.last_mut().unwrap() {
1597 route_hop.node_features = features.to_context();
1603 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1604 payment_params: Some(payment_params.clone()),
1606 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1610 // When an adversarial intermediary node observes a payment, it may be able to infer its
1611 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1612 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1613 // payment path by adding a randomized 'shadow route' offset to the final hop.
1614 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]) {
1615 let network_channels = network_graph.channels();
1616 let network_nodes = network_graph.nodes();
1618 for path in route.paths.iter_mut() {
1619 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1621 // Remember the last three nodes of the random walk and avoid looping back on them.
1622 // Init with the last three nodes from the actual path, if possible.
1623 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1624 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1625 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1627 // Choose the last publicly known node as the starting point for the random walk.
1628 let mut cur_hop: Option<NodeId> = None;
1629 let mut path_nonce = [0u8; 12];
1630 if let Some(starting_hop) = path.iter().rev()
1631 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1632 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1633 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1636 // Init PRNG with the path-dependant nonce, which is static for private paths.
1637 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1638 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
1640 // Pick a random path length in [1 .. 3]
1641 prng.process_in_place(&mut random_path_bytes);
1642 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
1644 for random_hop in 0..random_walk_length {
1645 // If we don't find a suitable offset in the public network graph, we default to
1646 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1647 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
1649 if let Some(cur_node_id) = cur_hop {
1650 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
1651 // Randomly choose the next unvisited hop.
1652 prng.process_in_place(&mut random_path_bytes);
1653 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
1654 .checked_rem(cur_node.channels.len())
1655 .and_then(|index| cur_node.channels.get(index))
1656 .and_then(|id| network_channels.get(id)) {
1657 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
1658 if !nodes_to_avoid.iter().any(|x| x == next_id) {
1659 nodes_to_avoid[random_hop] = *next_id;
1660 dir_info.direction().map(|channel_update_info| {
1661 random_hop_offset = channel_update_info.cltv_expiry_delta.into();
1662 cur_hop = Some(*next_id);
1670 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
1671 .checked_add(random_hop_offset)
1672 .unwrap_or(shadow_ctlv_expiry_delta_offset);
1675 // Limit the total offset to reduce the worst-case locked liquidity timevalue
1676 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
1677 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
1679 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
1680 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
1681 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
1682 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
1683 max_path_offset = cmp::max(
1684 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
1685 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
1686 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
1688 // Add 'shadow' CLTV offset to the final hop
1689 if let Some(last_hop) = path.last_mut() {
1690 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
1691 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
1698 use routing::network_graph::{NetworkGraph, NetGraphMsgHandler, NodeId};
1699 use routing::router::{get_route, add_random_cltv_offset, default_node_features, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA};
1700 use routing::scoring::Score;
1701 use chain::transaction::OutPoint;
1702 use chain::keysinterface::KeysInterface;
1703 use ln::features::{ChannelFeatures, InitFeatures, InvoiceFeatures, NodeFeatures};
1704 use ln::msgs::{ErrorAction, LightningError, OptionalField, UnsignedChannelAnnouncement, ChannelAnnouncement, RoutingMessageHandler,
1705 NodeAnnouncement, UnsignedNodeAnnouncement, ChannelUpdate, UnsignedChannelUpdate};
1706 use ln::channelmanager;
1707 use util::test_utils;
1708 use util::chacha20::ChaCha20;
1709 use util::ser::Writeable;
1711 use util::ser::Writer;
1713 use bitcoin::hashes::sha256d::Hash as Sha256dHash;
1714 use bitcoin::hashes::Hash;
1715 use bitcoin::network::constants::Network;
1716 use bitcoin::blockdata::constants::genesis_block;
1717 use bitcoin::blockdata::script::Builder;
1718 use bitcoin::blockdata::opcodes;
1719 use bitcoin::blockdata::transaction::TxOut;
1723 use bitcoin::secp256k1::key::{PublicKey,SecretKey};
1724 use bitcoin::secp256k1::{Secp256k1, All};
1727 use sync::{self, Arc};
1729 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
1730 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
1731 channelmanager::ChannelDetails {
1732 channel_id: [0; 32],
1733 counterparty: channelmanager::ChannelCounterparty {
1736 unspendable_punishment_reserve: 0,
1737 forwarding_info: None,
1739 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
1742 inbound_scid_alias: None,
1743 channel_value_satoshis: 0,
1746 outbound_capacity_msat,
1747 inbound_capacity_msat: 42,
1748 unspendable_punishment_reserve: None,
1749 confirmations_required: None,
1750 force_close_spend_delay: None,
1751 is_outbound: true, is_funding_locked: true,
1752 is_usable: true, is_public: true,
1756 // Using the same keys for LN and BTC ids
1758 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1759 secp_ctx: &Secp256k1<All>, node_1_privkey: &SecretKey, node_2_privkey: &SecretKey, features: ChannelFeatures, short_channel_id: u64
1761 let node_id_1 = PublicKey::from_secret_key(&secp_ctx, node_1_privkey);
1762 let node_id_2 = PublicKey::from_secret_key(&secp_ctx, node_2_privkey);
1764 let unsigned_announcement = UnsignedChannelAnnouncement {
1766 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1770 bitcoin_key_1: node_id_1,
1771 bitcoin_key_2: node_id_2,
1772 excess_data: Vec::new(),
1775 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1776 let valid_announcement = ChannelAnnouncement {
1777 node_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1778 node_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1779 bitcoin_signature_1: secp_ctx.sign(&msghash, node_1_privkey),
1780 bitcoin_signature_2: secp_ctx.sign(&msghash, node_2_privkey),
1781 contents: unsigned_announcement.clone(),
1783 match net_graph_msg_handler.handle_channel_announcement(&valid_announcement) {
1784 Ok(res) => assert!(res),
1790 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1791 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, update: UnsignedChannelUpdate
1793 let msghash = hash_to_message!(&Sha256dHash::hash(&update.encode()[..])[..]);
1794 let valid_channel_update = ChannelUpdate {
1795 signature: secp_ctx.sign(&msghash, node_privkey),
1796 contents: update.clone()
1799 match net_graph_msg_handler.handle_channel_update(&valid_channel_update) {
1800 Ok(res) => assert!(res),
1805 fn add_or_update_node(
1806 net_graph_msg_handler: &NetGraphMsgHandler<Arc<NetworkGraph>, Arc<test_utils::TestChainSource>, Arc<test_utils::TestLogger>>,
1807 secp_ctx: &Secp256k1<All>, node_privkey: &SecretKey, features: NodeFeatures, timestamp: u32
1809 let node_id = PublicKey::from_secret_key(&secp_ctx, node_privkey);
1810 let unsigned_announcement = UnsignedNodeAnnouncement {
1816 addresses: Vec::new(),
1817 excess_address_data: Vec::new(),
1818 excess_data: Vec::new(),
1820 let msghash = hash_to_message!(&Sha256dHash::hash(&unsigned_announcement.encode()[..])[..]);
1821 let valid_announcement = NodeAnnouncement {
1822 signature: secp_ctx.sign(&msghash, node_privkey),
1823 contents: unsigned_announcement.clone()
1826 match net_graph_msg_handler.handle_node_announcement(&valid_announcement) {
1832 fn get_nodes(secp_ctx: &Secp256k1<All>) -> (SecretKey, PublicKey, Vec<SecretKey>, Vec<PublicKey>) {
1833 let privkeys: Vec<SecretKey> = (2..10).map(|i| {
1834 SecretKey::from_slice(&hex::decode(format!("{:02x}", i).repeat(32)).unwrap()[..]).unwrap()
1837 let pubkeys = privkeys.iter().map(|secret| PublicKey::from_secret_key(&secp_ctx, secret)).collect();
1839 let our_privkey = SecretKey::from_slice(&hex::decode("01".repeat(32)).unwrap()[..]).unwrap();
1840 let our_id = PublicKey::from_secret_key(&secp_ctx, &our_privkey);
1842 (our_privkey, our_id, privkeys, pubkeys)
1845 fn id_to_feature_flags(id: u8) -> Vec<u8> {
1846 // Set the feature flags to the id'th odd (ie non-required) feature bit so that we can
1847 // test for it later.
1848 let idx = (id - 1) * 2 + 1;
1850 vec![1 << (idx - 8*3), 0, 0, 0]
1851 } else if idx > 8*2 {
1852 vec![1 << (idx - 8*2), 0, 0]
1853 } else if idx > 8*1 {
1854 vec![1 << (idx - 8*1), 0]
1860 fn build_graph() -> (
1862 sync::Arc<NetworkGraph>,
1863 NetGraphMsgHandler<sync::Arc<NetworkGraph>, sync::Arc<test_utils::TestChainSource>, sync::Arc<crate::util::test_utils::TestLogger>>,
1864 sync::Arc<test_utils::TestChainSource>,
1865 sync::Arc<test_utils::TestLogger>,
1867 let secp_ctx = Secp256k1::new();
1868 let logger = Arc::new(test_utils::TestLogger::new());
1869 let chain_monitor = Arc::new(test_utils::TestChainSource::new(Network::Testnet));
1870 let network_graph = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
1871 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network_graph), None, Arc::clone(&logger));
1872 // Build network from our_id to node6:
1874 // -1(1)2- node0 -1(3)2-
1876 // our_id -1(12)2- node7 -1(13)2--- node2
1878 // -1(2)2- node1 -1(4)2-
1881 // chan1 1-to-2: disabled
1882 // chan1 2-to-1: enabled, 0 fee
1884 // chan2 1-to-2: enabled, ignored fee
1885 // chan2 2-to-1: enabled, 0 fee
1887 // chan3 1-to-2: enabled, 0 fee
1888 // chan3 2-to-1: enabled, 100 msat fee
1890 // chan4 1-to-2: enabled, 100% fee
1891 // chan4 2-to-1: enabled, 0 fee
1893 // chan12 1-to-2: enabled, ignored fee
1894 // chan12 2-to-1: enabled, 0 fee
1896 // chan13 1-to-2: enabled, 200% fee
1897 // chan13 2-to-1: enabled, 0 fee
1900 // -1(5)2- node3 -1(8)2--
1904 // node2--1(6)2- node4 -1(9)2--- node6 (not in global route map)
1906 // -1(7)2- node5 -1(10)2-
1908 // Channels 5, 8, 9 and 10 are private channels.
1910 // chan5 1-to-2: enabled, 100 msat fee
1911 // chan5 2-to-1: enabled, 0 fee
1913 // chan6 1-to-2: enabled, 0 fee
1914 // chan6 2-to-1: enabled, 0 fee
1916 // chan7 1-to-2: enabled, 100% fee
1917 // chan7 2-to-1: enabled, 0 fee
1919 // chan8 1-to-2: enabled, variable fee (0 then 1000 msat)
1920 // chan8 2-to-1: enabled, 0 fee
1922 // chan9 1-to-2: enabled, 1001 msat fee
1923 // chan9 2-to-1: enabled, 0 fee
1925 // chan10 1-to-2: enabled, 0 fee
1926 // chan10 2-to-1: enabled, 0 fee
1928 // chan11 1-to-2: enabled, 0 fee
1929 // chan11 2-to-1: enabled, 0 fee
1931 let (our_privkey, _, privkeys, _) = get_nodes(&secp_ctx);
1933 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[0], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
1934 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
1935 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1936 short_channel_id: 1,
1939 cltv_expiry_delta: 0,
1940 htlc_minimum_msat: 0,
1941 htlc_maximum_msat: OptionalField::Absent,
1943 fee_proportional_millionths: 0,
1944 excess_data: Vec::new()
1947 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
1949 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
1950 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1951 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1952 short_channel_id: 2,
1955 cltv_expiry_delta: (5 << 4) | 3,
1956 htlc_minimum_msat: 0,
1957 htlc_maximum_msat: OptionalField::Absent,
1958 fee_base_msat: u32::max_value(),
1959 fee_proportional_millionths: u32::max_value(),
1960 excess_data: Vec::new()
1962 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
1963 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1964 short_channel_id: 2,
1967 cltv_expiry_delta: 0,
1968 htlc_minimum_msat: 0,
1969 htlc_maximum_msat: OptionalField::Absent,
1971 fee_proportional_millionths: 0,
1972 excess_data: Vec::new()
1975 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
1977 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[7], ChannelFeatures::from_le_bytes(id_to_feature_flags(12)), 12);
1978 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
1979 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1980 short_channel_id: 12,
1983 cltv_expiry_delta: (5 << 4) | 3,
1984 htlc_minimum_msat: 0,
1985 htlc_maximum_msat: OptionalField::Absent,
1986 fee_base_msat: u32::max_value(),
1987 fee_proportional_millionths: u32::max_value(),
1988 excess_data: Vec::new()
1990 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
1991 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
1992 short_channel_id: 12,
1995 cltv_expiry_delta: 0,
1996 htlc_minimum_msat: 0,
1997 htlc_maximum_msat: OptionalField::Absent,
1999 fee_proportional_millionths: 0,
2000 excess_data: Vec::new()
2003 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], NodeFeatures::from_le_bytes(id_to_feature_flags(8)), 0);
2005 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
2006 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2007 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2008 short_channel_id: 3,
2011 cltv_expiry_delta: (3 << 4) | 1,
2012 htlc_minimum_msat: 0,
2013 htlc_maximum_msat: OptionalField::Absent,
2015 fee_proportional_millionths: 0,
2016 excess_data: Vec::new()
2018 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2019 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2020 short_channel_id: 3,
2023 cltv_expiry_delta: (3 << 4) | 2,
2024 htlc_minimum_msat: 0,
2025 htlc_maximum_msat: OptionalField::Absent,
2027 fee_proportional_millionths: 0,
2028 excess_data: Vec::new()
2031 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
2032 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2033 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2034 short_channel_id: 4,
2037 cltv_expiry_delta: (4 << 4) | 1,
2038 htlc_minimum_msat: 0,
2039 htlc_maximum_msat: OptionalField::Absent,
2041 fee_proportional_millionths: 1000000,
2042 excess_data: Vec::new()
2044 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2045 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2046 short_channel_id: 4,
2049 cltv_expiry_delta: (4 << 4) | 2,
2050 htlc_minimum_msat: 0,
2051 htlc_maximum_msat: OptionalField::Absent,
2053 fee_proportional_millionths: 0,
2054 excess_data: Vec::new()
2057 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(13)), 13);
2058 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2059 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2060 short_channel_id: 13,
2063 cltv_expiry_delta: (13 << 4) | 1,
2064 htlc_minimum_msat: 0,
2065 htlc_maximum_msat: OptionalField::Absent,
2067 fee_proportional_millionths: 2000000,
2068 excess_data: Vec::new()
2070 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2071 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2072 short_channel_id: 13,
2075 cltv_expiry_delta: (13 << 4) | 2,
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[2], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
2085 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
2086 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2087 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2088 short_channel_id: 6,
2091 cltv_expiry_delta: (6 << 4) | 1,
2092 htlc_minimum_msat: 0,
2093 htlc_maximum_msat: OptionalField::Absent,
2095 fee_proportional_millionths: 0,
2096 excess_data: Vec::new()
2098 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2099 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2100 short_channel_id: 6,
2103 cltv_expiry_delta: (6 << 4) | 2,
2104 htlc_minimum_msat: 0,
2105 htlc_maximum_msat: OptionalField::Absent,
2107 fee_proportional_millionths: 0,
2108 excess_data: Vec::new(),
2111 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(11)), 11);
2112 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
2113 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2114 short_channel_id: 11,
2117 cltv_expiry_delta: (11 << 4) | 1,
2118 htlc_minimum_msat: 0,
2119 htlc_maximum_msat: OptionalField::Absent,
2121 fee_proportional_millionths: 0,
2122 excess_data: Vec::new()
2124 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
2125 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2126 short_channel_id: 11,
2129 cltv_expiry_delta: (11 << 4) | 2,
2130 htlc_minimum_msat: 0,
2131 htlc_maximum_msat: OptionalField::Absent,
2133 fee_proportional_millionths: 0,
2134 excess_data: Vec::new()
2137 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(5)), 0);
2139 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
2141 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[5], ChannelFeatures::from_le_bytes(id_to_feature_flags(7)), 7);
2142 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2143 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2144 short_channel_id: 7,
2147 cltv_expiry_delta: (7 << 4) | 1,
2148 htlc_minimum_msat: 0,
2149 htlc_maximum_msat: OptionalField::Absent,
2151 fee_proportional_millionths: 1000000,
2152 excess_data: Vec::new()
2154 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[5], UnsignedChannelUpdate {
2155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2156 short_channel_id: 7,
2159 cltv_expiry_delta: (7 << 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_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[5], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
2169 (secp_ctx, network_graph, net_graph_msg_handler, chain_monitor, logger)
2173 fn simple_route_test() {
2174 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2175 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2176 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2177 let scorer = test_utils::TestScorer::with_penalty(0);
2178 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2179 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2181 // Simple route to 2 via 1
2183 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) {
2184 assert_eq!(err, "Cannot send a payment of 0 msat");
2185 } else { panic!(); }
2187 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2188 assert_eq!(route.paths[0].len(), 2);
2190 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2191 assert_eq!(route.paths[0][0].short_channel_id, 2);
2192 assert_eq!(route.paths[0][0].fee_msat, 100);
2193 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2194 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2195 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2197 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2198 assert_eq!(route.paths[0][1].short_channel_id, 4);
2199 assert_eq!(route.paths[0][1].fee_msat, 100);
2200 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2201 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2202 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2206 fn invalid_first_hop_test() {
2207 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2208 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2209 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2210 let scorer = test_utils::TestScorer::with_penalty(0);
2211 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2212 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2214 // Simple route to 2 via 1
2216 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2218 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2219 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) {
2220 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2221 } else { panic!(); }
2223 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2224 assert_eq!(route.paths[0].len(), 2);
2228 fn htlc_minimum_test() {
2229 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2230 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2231 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2232 let scorer = test_utils::TestScorer::with_penalty(0);
2233 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2234 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2236 // Simple route to 2 via 1
2238 // Disable other paths
2239 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2240 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2241 short_channel_id: 12,
2243 flags: 2, // to disable
2244 cltv_expiry_delta: 0,
2245 htlc_minimum_msat: 0,
2246 htlc_maximum_msat: OptionalField::Absent,
2248 fee_proportional_millionths: 0,
2249 excess_data: Vec::new()
2251 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2252 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2253 short_channel_id: 3,
2255 flags: 2, // to disable
2256 cltv_expiry_delta: 0,
2257 htlc_minimum_msat: 0,
2258 htlc_maximum_msat: OptionalField::Absent,
2260 fee_proportional_millionths: 0,
2261 excess_data: Vec::new()
2263 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2264 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2265 short_channel_id: 13,
2267 flags: 2, // to disable
2268 cltv_expiry_delta: 0,
2269 htlc_minimum_msat: 0,
2270 htlc_maximum_msat: OptionalField::Absent,
2272 fee_proportional_millionths: 0,
2273 excess_data: Vec::new()
2275 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2276 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2277 short_channel_id: 6,
2279 flags: 2, // to disable
2280 cltv_expiry_delta: 0,
2281 htlc_minimum_msat: 0,
2282 htlc_maximum_msat: OptionalField::Absent,
2284 fee_proportional_millionths: 0,
2285 excess_data: Vec::new()
2287 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2288 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2289 short_channel_id: 7,
2291 flags: 2, // to disable
2292 cltv_expiry_delta: 0,
2293 htlc_minimum_msat: 0,
2294 htlc_maximum_msat: OptionalField::Absent,
2296 fee_proportional_millionths: 0,
2297 excess_data: Vec::new()
2300 // Check against amount_to_transfer_over_msat.
2301 // Set minimal HTLC of 200_000_000 msat.
2302 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2303 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2304 short_channel_id: 2,
2307 cltv_expiry_delta: 0,
2308 htlc_minimum_msat: 200_000_000,
2309 htlc_maximum_msat: OptionalField::Absent,
2311 fee_proportional_millionths: 0,
2312 excess_data: Vec::new()
2315 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2317 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2318 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2319 short_channel_id: 4,
2322 cltv_expiry_delta: 0,
2323 htlc_minimum_msat: 0,
2324 htlc_maximum_msat: OptionalField::Present(199_999_999),
2326 fee_proportional_millionths: 0,
2327 excess_data: Vec::new()
2330 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2331 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) {
2332 assert_eq!(err, "Failed to find a path to the given destination");
2333 } else { panic!(); }
2335 // Lift the restriction on the first hop.
2336 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2337 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2338 short_channel_id: 2,
2341 cltv_expiry_delta: 0,
2342 htlc_minimum_msat: 0,
2343 htlc_maximum_msat: OptionalField::Absent,
2345 fee_proportional_millionths: 0,
2346 excess_data: Vec::new()
2349 // A payment above the minimum should pass
2350 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();
2351 assert_eq!(route.paths[0].len(), 2);
2355 fn htlc_minimum_overpay_test() {
2356 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2357 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2358 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
2359 let scorer = test_utils::TestScorer::with_penalty(0);
2360 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2361 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2363 // A route to node#2 via two paths.
2364 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2365 // Thus, they can't send 60 without overpaying.
2366 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2367 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2368 short_channel_id: 2,
2371 cltv_expiry_delta: 0,
2372 htlc_minimum_msat: 35_000,
2373 htlc_maximum_msat: OptionalField::Present(40_000),
2375 fee_proportional_millionths: 0,
2376 excess_data: Vec::new()
2378 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2379 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2380 short_channel_id: 12,
2383 cltv_expiry_delta: 0,
2384 htlc_minimum_msat: 35_000,
2385 htlc_maximum_msat: OptionalField::Present(40_000),
2387 fee_proportional_millionths: 0,
2388 excess_data: Vec::new()
2392 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2393 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2394 short_channel_id: 13,
2397 cltv_expiry_delta: 0,
2398 htlc_minimum_msat: 0,
2399 htlc_maximum_msat: OptionalField::Absent,
2401 fee_proportional_millionths: 0,
2402 excess_data: Vec::new()
2404 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2405 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2406 short_channel_id: 4,
2409 cltv_expiry_delta: 0,
2410 htlc_minimum_msat: 0,
2411 htlc_maximum_msat: OptionalField::Absent,
2413 fee_proportional_millionths: 0,
2414 excess_data: Vec::new()
2417 // Disable other paths
2418 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2419 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2420 short_channel_id: 1,
2422 flags: 2, // to disable
2423 cltv_expiry_delta: 0,
2424 htlc_minimum_msat: 0,
2425 htlc_maximum_msat: OptionalField::Absent,
2427 fee_proportional_millionths: 0,
2428 excess_data: Vec::new()
2431 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2432 // Overpay fees to hit htlc_minimum_msat.
2433 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2434 // TODO: this could be better balanced to overpay 10k and not 15k.
2435 assert_eq!(overpaid_fees, 15_000);
2437 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2438 // while taking even more fee to match htlc_minimum_msat.
2439 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2440 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2441 short_channel_id: 12,
2444 cltv_expiry_delta: 0,
2445 htlc_minimum_msat: 65_000,
2446 htlc_maximum_msat: OptionalField::Present(80_000),
2448 fee_proportional_millionths: 0,
2449 excess_data: Vec::new()
2451 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2452 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2453 short_channel_id: 2,
2456 cltv_expiry_delta: 0,
2457 htlc_minimum_msat: 0,
2458 htlc_maximum_msat: OptionalField::Absent,
2460 fee_proportional_millionths: 0,
2461 excess_data: Vec::new()
2463 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2464 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2465 short_channel_id: 4,
2468 cltv_expiry_delta: 0,
2469 htlc_minimum_msat: 0,
2470 htlc_maximum_msat: OptionalField::Absent,
2472 fee_proportional_millionths: 100_000,
2473 excess_data: Vec::new()
2476 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2477 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2478 assert_eq!(route.paths.len(), 1);
2479 assert_eq!(route.paths[0][0].short_channel_id, 12);
2480 let fees = route.paths[0][0].fee_msat;
2481 assert_eq!(fees, 5_000);
2483 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2484 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2485 // the other channel.
2486 assert_eq!(route.paths.len(), 1);
2487 assert_eq!(route.paths[0][0].short_channel_id, 2);
2488 let fees = route.paths[0][0].fee_msat;
2489 assert_eq!(fees, 5_000);
2493 fn disable_channels_test() {
2494 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2495 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2496 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2497 let scorer = test_utils::TestScorer::with_penalty(0);
2498 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2499 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2501 // // Disable channels 4 and 12 by flags=2
2502 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2503 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2504 short_channel_id: 4,
2506 flags: 2, // to disable
2507 cltv_expiry_delta: 0,
2508 htlc_minimum_msat: 0,
2509 htlc_maximum_msat: OptionalField::Absent,
2511 fee_proportional_millionths: 0,
2512 excess_data: Vec::new()
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,
2518 flags: 2, // to disable
2519 cltv_expiry_delta: 0,
2520 htlc_minimum_msat: 0,
2521 htlc_maximum_msat: OptionalField::Absent,
2523 fee_proportional_millionths: 0,
2524 excess_data: Vec::new()
2527 // If all the channels require some features we don't understand, route should fail
2528 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) {
2529 assert_eq!(err, "Failed to find a path to the given destination");
2530 } else { panic!(); }
2532 // If we specify a channel to node7, that overrides our local channel view and that gets used
2533 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2534 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();
2535 assert_eq!(route.paths[0].len(), 2);
2537 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2538 assert_eq!(route.paths[0][0].short_channel_id, 42);
2539 assert_eq!(route.paths[0][0].fee_msat, 200);
2540 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2541 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2542 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2544 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2545 assert_eq!(route.paths[0][1].short_channel_id, 13);
2546 assert_eq!(route.paths[0][1].fee_msat, 100);
2547 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2548 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2549 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2553 fn disable_node_test() {
2554 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2555 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2556 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2557 let scorer = test_utils::TestScorer::with_penalty(0);
2558 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2559 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2561 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2562 let mut unknown_features = NodeFeatures::known();
2563 unknown_features.set_unknown_feature_required();
2564 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2565 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2566 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2568 // If all nodes require some features we don't understand, route should fail
2569 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) {
2570 assert_eq!(err, "Failed to find a path to the given destination");
2571 } else { panic!(); }
2573 // If we specify a channel to node7, that overrides our local channel view and that gets used
2574 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2575 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();
2576 assert_eq!(route.paths[0].len(), 2);
2578 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2579 assert_eq!(route.paths[0][0].short_channel_id, 42);
2580 assert_eq!(route.paths[0][0].fee_msat, 200);
2581 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2582 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2583 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2585 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2586 assert_eq!(route.paths[0][1].short_channel_id, 13);
2587 assert_eq!(route.paths[0][1].fee_msat, 100);
2588 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2589 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2590 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2592 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2593 // naively) assume that the user checked the feature bits on the invoice, which override
2594 // the node_announcement.
2598 fn our_chans_test() {
2599 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2600 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2601 let scorer = test_utils::TestScorer::with_penalty(0);
2602 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2603 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2605 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2606 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2607 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2608 assert_eq!(route.paths[0].len(), 3);
2610 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2611 assert_eq!(route.paths[0][0].short_channel_id, 2);
2612 assert_eq!(route.paths[0][0].fee_msat, 200);
2613 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2614 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2615 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2617 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2618 assert_eq!(route.paths[0][1].short_channel_id, 4);
2619 assert_eq!(route.paths[0][1].fee_msat, 100);
2620 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2621 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2622 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2624 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2625 assert_eq!(route.paths[0][2].short_channel_id, 3);
2626 assert_eq!(route.paths[0][2].fee_msat, 100);
2627 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2628 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2629 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2631 // If we specify a channel to node7, that overrides our local channel view and that gets used
2632 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2633 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2634 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();
2635 assert_eq!(route.paths[0].len(), 2);
2637 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2638 assert_eq!(route.paths[0][0].short_channel_id, 42);
2639 assert_eq!(route.paths[0][0].fee_msat, 200);
2640 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2641 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2642 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2644 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2645 assert_eq!(route.paths[0][1].short_channel_id, 13);
2646 assert_eq!(route.paths[0][1].fee_msat, 100);
2647 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2648 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2649 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2652 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2653 let zero_fees = RoutingFees {
2655 proportional_millionths: 0,
2657 vec![RouteHint(vec![RouteHintHop {
2658 src_node_id: nodes[3],
2659 short_channel_id: 8,
2661 cltv_expiry_delta: (8 << 4) | 1,
2662 htlc_minimum_msat: None,
2663 htlc_maximum_msat: None,
2665 ]), RouteHint(vec![RouteHintHop {
2666 src_node_id: nodes[4],
2667 short_channel_id: 9,
2670 proportional_millionths: 0,
2672 cltv_expiry_delta: (9 << 4) | 1,
2673 htlc_minimum_msat: None,
2674 htlc_maximum_msat: None,
2675 }]), RouteHint(vec![RouteHintHop {
2676 src_node_id: nodes[5],
2677 short_channel_id: 10,
2679 cltv_expiry_delta: (10 << 4) | 1,
2680 htlc_minimum_msat: None,
2681 htlc_maximum_msat: None,
2685 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2686 let zero_fees = RoutingFees {
2688 proportional_millionths: 0,
2690 vec![RouteHint(vec![RouteHintHop {
2691 src_node_id: nodes[2],
2692 short_channel_id: 5,
2695 proportional_millionths: 0,
2697 cltv_expiry_delta: (5 << 4) | 1,
2698 htlc_minimum_msat: None,
2699 htlc_maximum_msat: None,
2701 src_node_id: nodes[3],
2702 short_channel_id: 8,
2704 cltv_expiry_delta: (8 << 4) | 1,
2705 htlc_minimum_msat: None,
2706 htlc_maximum_msat: None,
2708 ]), RouteHint(vec![RouteHintHop {
2709 src_node_id: nodes[4],
2710 short_channel_id: 9,
2713 proportional_millionths: 0,
2715 cltv_expiry_delta: (9 << 4) | 1,
2716 htlc_minimum_msat: None,
2717 htlc_maximum_msat: None,
2718 }]), RouteHint(vec![RouteHintHop {
2719 src_node_id: nodes[5],
2720 short_channel_id: 10,
2722 cltv_expiry_delta: (10 << 4) | 1,
2723 htlc_minimum_msat: None,
2724 htlc_maximum_msat: None,
2729 fn partial_route_hint_test() {
2730 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2731 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2732 let scorer = test_utils::TestScorer::with_penalty(0);
2733 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2734 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2736 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2737 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2738 // RouteHint may be partially used by the algo to build the best path.
2740 // First check that last hop can't have its source as the payee.
2741 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2742 src_node_id: nodes[6],
2743 short_channel_id: 8,
2746 proportional_millionths: 0,
2748 cltv_expiry_delta: (8 << 4) | 1,
2749 htlc_minimum_msat: None,
2750 htlc_maximum_msat: None,
2753 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2754 invalid_last_hops.push(invalid_last_hop);
2756 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2757 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) {
2758 assert_eq!(err, "Route hint cannot have the payee as the source.");
2759 } else { panic!(); }
2762 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2763 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2764 assert_eq!(route.paths[0].len(), 5);
2766 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2767 assert_eq!(route.paths[0][0].short_channel_id, 2);
2768 assert_eq!(route.paths[0][0].fee_msat, 100);
2769 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2770 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2771 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2773 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2774 assert_eq!(route.paths[0][1].short_channel_id, 4);
2775 assert_eq!(route.paths[0][1].fee_msat, 0);
2776 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2777 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2778 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2780 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2781 assert_eq!(route.paths[0][2].short_channel_id, 6);
2782 assert_eq!(route.paths[0][2].fee_msat, 0);
2783 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2784 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2785 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2787 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2788 assert_eq!(route.paths[0][3].short_channel_id, 11);
2789 assert_eq!(route.paths[0][3].fee_msat, 0);
2790 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2791 // If we have a peer in the node map, we'll use their features here since we don't have
2792 // a way of figuring out their features from the invoice:
2793 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2794 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2796 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2797 assert_eq!(route.paths[0][4].short_channel_id, 8);
2798 assert_eq!(route.paths[0][4].fee_msat, 100);
2799 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2800 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2801 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2804 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2805 let zero_fees = RoutingFees {
2807 proportional_millionths: 0,
2809 vec![RouteHint(vec![RouteHintHop {
2810 src_node_id: nodes[3],
2811 short_channel_id: 8,
2813 cltv_expiry_delta: (8 << 4) | 1,
2814 htlc_minimum_msat: None,
2815 htlc_maximum_msat: None,
2816 }]), RouteHint(vec![
2818 ]), RouteHint(vec![RouteHintHop {
2819 src_node_id: nodes[5],
2820 short_channel_id: 10,
2822 cltv_expiry_delta: (10 << 4) | 1,
2823 htlc_minimum_msat: None,
2824 htlc_maximum_msat: None,
2829 fn ignores_empty_last_hops_test() {
2830 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2831 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2832 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2833 let scorer = test_utils::TestScorer::with_penalty(0);
2834 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2835 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2837 // Test handling of an empty RouteHint passed in Invoice.
2839 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2840 assert_eq!(route.paths[0].len(), 5);
2842 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2843 assert_eq!(route.paths[0][0].short_channel_id, 2);
2844 assert_eq!(route.paths[0][0].fee_msat, 100);
2845 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2846 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2847 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2849 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2850 assert_eq!(route.paths[0][1].short_channel_id, 4);
2851 assert_eq!(route.paths[0][1].fee_msat, 0);
2852 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2853 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2854 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2856 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2857 assert_eq!(route.paths[0][2].short_channel_id, 6);
2858 assert_eq!(route.paths[0][2].fee_msat, 0);
2859 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2860 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2861 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2863 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2864 assert_eq!(route.paths[0][3].short_channel_id, 11);
2865 assert_eq!(route.paths[0][3].fee_msat, 0);
2866 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2867 // If we have a peer in the node map, we'll use their features here since we don't have
2868 // a way of figuring out their features from the invoice:
2869 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2870 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2872 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2873 assert_eq!(route.paths[0][4].short_channel_id, 8);
2874 assert_eq!(route.paths[0][4].fee_msat, 100);
2875 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2876 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2877 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2880 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2882 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2883 let zero_fees = RoutingFees {
2885 proportional_millionths: 0,
2887 vec![RouteHint(vec![RouteHintHop {
2888 src_node_id: hint_hops[0],
2889 short_channel_id: 0xff00,
2892 proportional_millionths: 0,
2894 cltv_expiry_delta: (5 << 4) | 1,
2895 htlc_minimum_msat: None,
2896 htlc_maximum_msat: None,
2898 src_node_id: hint_hops[1],
2899 short_channel_id: 0xff01,
2901 cltv_expiry_delta: (8 << 4) | 1,
2902 htlc_minimum_msat: None,
2903 htlc_maximum_msat: None,
2908 fn multi_hint_last_hops_test() {
2909 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2910 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2911 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2912 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2913 let scorer = test_utils::TestScorer::with_penalty(0);
2914 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2915 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2916 // Test through channels 2, 3, 0xff00, 0xff01.
2917 // Test shows that multiple hop hints are considered.
2919 // Disabling channels 6 & 7 by flags=2
2920 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2921 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2922 short_channel_id: 6,
2924 flags: 2, // to disable
2925 cltv_expiry_delta: 0,
2926 htlc_minimum_msat: 0,
2927 htlc_maximum_msat: OptionalField::Absent,
2929 fee_proportional_millionths: 0,
2930 excess_data: Vec::new()
2932 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2933 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2934 short_channel_id: 7,
2936 flags: 2, // to disable
2937 cltv_expiry_delta: 0,
2938 htlc_minimum_msat: 0,
2939 htlc_maximum_msat: OptionalField::Absent,
2941 fee_proportional_millionths: 0,
2942 excess_data: Vec::new()
2945 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2946 assert_eq!(route.paths[0].len(), 4);
2948 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2949 assert_eq!(route.paths[0][0].short_channel_id, 2);
2950 assert_eq!(route.paths[0][0].fee_msat, 200);
2951 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2952 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2953 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2955 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2956 assert_eq!(route.paths[0][1].short_channel_id, 4);
2957 assert_eq!(route.paths[0][1].fee_msat, 100);
2958 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2959 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2960 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2962 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2963 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2964 assert_eq!(route.paths[0][2].fee_msat, 0);
2965 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2966 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2967 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2969 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2970 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
2971 assert_eq!(route.paths[0][3].fee_msat, 100);
2972 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
2973 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2974 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2978 fn private_multi_hint_last_hops_test() {
2979 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
2980 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2982 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
2983 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
2985 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
2986 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2987 let scorer = test_utils::TestScorer::with_penalty(0);
2988 // Test through channels 2, 3, 0xff00, 0xff01.
2989 // Test shows that multiple hop hints are considered.
2991 // Disabling channels 6 & 7 by flags=2
2992 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2993 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2994 short_channel_id: 6,
2996 flags: 2, // to disable
2997 cltv_expiry_delta: 0,
2998 htlc_minimum_msat: 0,
2999 htlc_maximum_msat: OptionalField::Absent,
3001 fee_proportional_millionths: 0,
3002 excess_data: Vec::new()
3004 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3005 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3006 short_channel_id: 7,
3008 flags: 2, // to disable
3009 cltv_expiry_delta: 0,
3010 htlc_minimum_msat: 0,
3011 htlc_maximum_msat: OptionalField::Absent,
3013 fee_proportional_millionths: 0,
3014 excess_data: Vec::new()
3017 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3018 assert_eq!(route.paths[0].len(), 4);
3020 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3021 assert_eq!(route.paths[0][0].short_channel_id, 2);
3022 assert_eq!(route.paths[0][0].fee_msat, 200);
3023 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3024 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3025 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3027 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3028 assert_eq!(route.paths[0][1].short_channel_id, 4);
3029 assert_eq!(route.paths[0][1].fee_msat, 100);
3030 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3031 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3032 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3034 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3035 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3036 assert_eq!(route.paths[0][2].fee_msat, 0);
3037 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3038 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3039 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3041 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3042 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3043 assert_eq!(route.paths[0][3].fee_msat, 100);
3044 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3045 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3046 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3049 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3050 let zero_fees = RoutingFees {
3052 proportional_millionths: 0,
3054 vec![RouteHint(vec![RouteHintHop {
3055 src_node_id: nodes[4],
3056 short_channel_id: 11,
3058 cltv_expiry_delta: (11 << 4) | 1,
3059 htlc_minimum_msat: None,
3060 htlc_maximum_msat: None,
3062 src_node_id: nodes[3],
3063 short_channel_id: 8,
3065 cltv_expiry_delta: (8 << 4) | 1,
3066 htlc_minimum_msat: None,
3067 htlc_maximum_msat: None,
3068 }]), RouteHint(vec![RouteHintHop {
3069 src_node_id: nodes[4],
3070 short_channel_id: 9,
3073 proportional_millionths: 0,
3075 cltv_expiry_delta: (9 << 4) | 1,
3076 htlc_minimum_msat: None,
3077 htlc_maximum_msat: None,
3078 }]), RouteHint(vec![RouteHintHop {
3079 src_node_id: nodes[5],
3080 short_channel_id: 10,
3082 cltv_expiry_delta: (10 << 4) | 1,
3083 htlc_minimum_msat: None,
3084 htlc_maximum_msat: None,
3089 fn last_hops_with_public_channel_test() {
3090 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3091 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3092 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3093 let scorer = test_utils::TestScorer::with_penalty(0);
3094 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3095 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3096 // This test shows that public routes can be present in the invoice
3097 // which would be handled in the same manner.
3099 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3100 assert_eq!(route.paths[0].len(), 5);
3102 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3103 assert_eq!(route.paths[0][0].short_channel_id, 2);
3104 assert_eq!(route.paths[0][0].fee_msat, 100);
3105 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3106 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3107 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3109 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3110 assert_eq!(route.paths[0][1].short_channel_id, 4);
3111 assert_eq!(route.paths[0][1].fee_msat, 0);
3112 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3113 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3114 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3116 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3117 assert_eq!(route.paths[0][2].short_channel_id, 6);
3118 assert_eq!(route.paths[0][2].fee_msat, 0);
3119 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3120 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3121 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3123 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3124 assert_eq!(route.paths[0][3].short_channel_id, 11);
3125 assert_eq!(route.paths[0][3].fee_msat, 0);
3126 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3127 // If we have a peer in the node map, we'll use their features here since we don't have
3128 // a way of figuring out their features from the invoice:
3129 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3130 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3132 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3133 assert_eq!(route.paths[0][4].short_channel_id, 8);
3134 assert_eq!(route.paths[0][4].fee_msat, 100);
3135 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3136 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3137 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3141 fn our_chans_last_hop_connect_test() {
3142 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3143 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3144 let scorer = test_utils::TestScorer::with_penalty(0);
3145 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3146 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3148 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3149 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3150 let mut last_hops = last_hops(&nodes);
3151 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3152 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();
3153 assert_eq!(route.paths[0].len(), 2);
3155 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3156 assert_eq!(route.paths[0][0].short_channel_id, 42);
3157 assert_eq!(route.paths[0][0].fee_msat, 0);
3158 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3159 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3160 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3162 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3163 assert_eq!(route.paths[0][1].short_channel_id, 8);
3164 assert_eq!(route.paths[0][1].fee_msat, 100);
3165 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3166 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3167 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3169 last_hops[0].0[0].fees.base_msat = 1000;
3171 // Revert to via 6 as the fee on 8 goes up
3172 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3173 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3174 assert_eq!(route.paths[0].len(), 4);
3176 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3177 assert_eq!(route.paths[0][0].short_channel_id, 2);
3178 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3179 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3180 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3181 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3183 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3184 assert_eq!(route.paths[0][1].short_channel_id, 4);
3185 assert_eq!(route.paths[0][1].fee_msat, 100);
3186 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3187 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3188 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3190 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3191 assert_eq!(route.paths[0][2].short_channel_id, 7);
3192 assert_eq!(route.paths[0][2].fee_msat, 0);
3193 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3194 // If we have a peer in the node map, we'll use their features here since we don't have
3195 // a way of figuring out their features from the invoice:
3196 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3197 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3199 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3200 assert_eq!(route.paths[0][3].short_channel_id, 10);
3201 assert_eq!(route.paths[0][3].fee_msat, 100);
3202 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3203 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3204 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3206 // ...but still use 8 for larger payments as 6 has a variable feerate
3207 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3208 assert_eq!(route.paths[0].len(), 5);
3210 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3211 assert_eq!(route.paths[0][0].short_channel_id, 2);
3212 assert_eq!(route.paths[0][0].fee_msat, 3000);
3213 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3214 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3215 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3217 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3218 assert_eq!(route.paths[0][1].short_channel_id, 4);
3219 assert_eq!(route.paths[0][1].fee_msat, 0);
3220 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3221 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3222 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3224 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3225 assert_eq!(route.paths[0][2].short_channel_id, 6);
3226 assert_eq!(route.paths[0][2].fee_msat, 0);
3227 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3228 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3229 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3231 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3232 assert_eq!(route.paths[0][3].short_channel_id, 11);
3233 assert_eq!(route.paths[0][3].fee_msat, 1000);
3234 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3235 // If we have a peer in the node map, we'll use their features here since we don't have
3236 // a way of figuring out their features from the invoice:
3237 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3238 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3240 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3241 assert_eq!(route.paths[0][4].short_channel_id, 8);
3242 assert_eq!(route.paths[0][4].fee_msat, 2000);
3243 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3244 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3245 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3248 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> {
3249 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3250 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3251 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3253 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3254 let last_hops = RouteHint(vec![RouteHintHop {
3255 src_node_id: middle_node_id,
3256 short_channel_id: 8,
3259 proportional_millionths: last_hop_fee_prop,
3261 cltv_expiry_delta: (8 << 4) | 1,
3262 htlc_minimum_msat: None,
3263 htlc_maximum_msat: last_hop_htlc_max,
3265 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3266 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3267 let scorer = test_utils::TestScorer::with_penalty(0);
3268 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3269 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3270 get_route(&source_node_id, &payment_params, &NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()).read_only(),
3271 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes)
3275 fn unannounced_path_test() {
3276 // We should be able to send a payment to a destination without any help of a routing graph
3277 // if we have a channel with a common counterparty that appears in the first and last hop
3279 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3281 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3282 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3283 assert_eq!(route.paths[0].len(), 2);
3285 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3286 assert_eq!(route.paths[0][0].short_channel_id, 42);
3287 assert_eq!(route.paths[0][0].fee_msat, 1001);
3288 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3289 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3290 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3292 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3293 assert_eq!(route.paths[0][1].short_channel_id, 8);
3294 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3295 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3296 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3297 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3301 fn overflow_unannounced_path_test_liquidity_underflow() {
3302 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3303 // the last-hop had a fee which overflowed a u64, we'd panic.
3304 // This was due to us adding the first-hop from us unconditionally, causing us to think
3305 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3306 // In this test, we previously hit a subtraction underflow due to having less available
3307 // liquidity at the last hop than 0.
3308 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());
3312 fn overflow_unannounced_path_test_feerate_overflow() {
3313 // This tests for the same case as above, except instead of hitting a subtraction
3314 // underflow, we hit a case where the fee charged at a hop overflowed.
3315 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());
3319 fn available_amount_while_routing_test() {
3320 // Tests whether we choose the correct available channel amount while routing.
3322 let (secp_ctx, network_graph, mut net_graph_msg_handler, chain_monitor, logger) = build_graph();
3323 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3324 let scorer = test_utils::TestScorer::with_penalty(0);
3325 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3326 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3327 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3329 // We will use a simple single-path route from
3330 // our node to node2 via node0: channels {1, 3}.
3332 // First disable all other paths.
3333 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3334 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3335 short_channel_id: 2,
3338 cltv_expiry_delta: 0,
3339 htlc_minimum_msat: 0,
3340 htlc_maximum_msat: OptionalField::Present(100_000),
3342 fee_proportional_millionths: 0,
3343 excess_data: Vec::new()
3345 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3346 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3347 short_channel_id: 12,
3350 cltv_expiry_delta: 0,
3351 htlc_minimum_msat: 0,
3352 htlc_maximum_msat: OptionalField::Present(100_000),
3354 fee_proportional_millionths: 0,
3355 excess_data: Vec::new()
3358 // Make the first channel (#1) very permissive,
3359 // and we will be testing all limits on the second channel.
3360 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3361 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3362 short_channel_id: 1,
3365 cltv_expiry_delta: 0,
3366 htlc_minimum_msat: 0,
3367 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3369 fee_proportional_millionths: 0,
3370 excess_data: Vec::new()
3373 // First, let's see if routing works if we have absolutely no idea about the available amount.
3374 // In this case, it should be set to 250_000 sats.
3375 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3376 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3377 short_channel_id: 3,
3380 cltv_expiry_delta: 0,
3381 htlc_minimum_msat: 0,
3382 htlc_maximum_msat: OptionalField::Absent,
3384 fee_proportional_millionths: 0,
3385 excess_data: Vec::new()
3389 // Attempt to route more than available results in a failure.
3390 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3391 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3392 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3393 } else { panic!(); }
3397 // Now, attempt to route an exact amount we have should be fine.
3398 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();
3399 assert_eq!(route.paths.len(), 1);
3400 let path = route.paths.last().unwrap();
3401 assert_eq!(path.len(), 2);
3402 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3403 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3406 // Check that setting outbound_capacity_msat in first_hops limits the channels.
3407 // Disable channel #1 and use another first hop.
3408 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3409 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3410 short_channel_id: 1,
3413 cltv_expiry_delta: 0,
3414 htlc_minimum_msat: 0,
3415 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3417 fee_proportional_millionths: 0,
3418 excess_data: Vec::new()
3421 // Now, limit the first_hop by the outbound_capacity_msat of 200_000 sats.
3422 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3425 // Attempt to route more than available results in a failure.
3426 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3427 &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) {
3428 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3429 } else { panic!(); }
3433 // Now, attempt to route an exact amount we have should be fine.
3434 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();
3435 assert_eq!(route.paths.len(), 1);
3436 let path = route.paths.last().unwrap();
3437 assert_eq!(path.len(), 2);
3438 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3439 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3442 // Enable channel #1 back.
3443 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3444 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3445 short_channel_id: 1,
3448 cltv_expiry_delta: 0,
3449 htlc_minimum_msat: 0,
3450 htlc_maximum_msat: OptionalField::Present(1_000_000_000),
3452 fee_proportional_millionths: 0,
3453 excess_data: Vec::new()
3457 // Now let's see if routing works if we know only htlc_maximum_msat.
3458 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3459 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3460 short_channel_id: 3,
3463 cltv_expiry_delta: 0,
3464 htlc_minimum_msat: 0,
3465 htlc_maximum_msat: OptionalField::Present(15_000),
3467 fee_proportional_millionths: 0,
3468 excess_data: Vec::new()
3472 // Attempt to route more than available results in a failure.
3473 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3474 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3475 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3476 } else { panic!(); }
3480 // Now, attempt to route an exact amount we have should be fine.
3481 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3482 assert_eq!(route.paths.len(), 1);
3483 let path = route.paths.last().unwrap();
3484 assert_eq!(path.len(), 2);
3485 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3486 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3489 // Now let's see if routing works if we know only capacity from the UTXO.
3491 // We can't change UTXO capacity on the fly, so we'll disable
3492 // the existing channel and add another one with the capacity we need.
3493 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3494 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3495 short_channel_id: 3,
3498 cltv_expiry_delta: 0,
3499 htlc_minimum_msat: 0,
3500 htlc_maximum_msat: OptionalField::Absent,
3502 fee_proportional_millionths: 0,
3503 excess_data: Vec::new()
3506 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3507 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3508 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3509 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3510 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3512 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3513 net_graph_msg_handler.add_chain_access(Some(chain_monitor));
3515 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3516 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3517 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3518 short_channel_id: 333,
3521 cltv_expiry_delta: (3 << 4) | 1,
3522 htlc_minimum_msat: 0,
3523 htlc_maximum_msat: OptionalField::Absent,
3525 fee_proportional_millionths: 0,
3526 excess_data: Vec::new()
3528 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3529 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3530 short_channel_id: 333,
3533 cltv_expiry_delta: (3 << 4) | 2,
3534 htlc_minimum_msat: 0,
3535 htlc_maximum_msat: OptionalField::Absent,
3537 fee_proportional_millionths: 0,
3538 excess_data: Vec::new()
3542 // Attempt to route more than available results in a failure.
3543 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3544 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3545 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3546 } else { panic!(); }
3550 // Now, attempt to route an exact amount we have should be fine.
3551 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3552 assert_eq!(route.paths.len(), 1);
3553 let path = route.paths.last().unwrap();
3554 assert_eq!(path.len(), 2);
3555 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3556 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3559 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3560 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3561 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3562 short_channel_id: 333,
3565 cltv_expiry_delta: 0,
3566 htlc_minimum_msat: 0,
3567 htlc_maximum_msat: OptionalField::Present(10_000),
3569 fee_proportional_millionths: 0,
3570 excess_data: Vec::new()
3574 // Attempt to route more than available results in a failure.
3575 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3576 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3577 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3578 } else { panic!(); }
3582 // Now, attempt to route an exact amount we have should be fine.
3583 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3584 assert_eq!(route.paths.len(), 1);
3585 let path = route.paths.last().unwrap();
3586 assert_eq!(path.len(), 2);
3587 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3588 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3593 fn available_liquidity_last_hop_test() {
3594 // Check that available liquidity properly limits the path even when only
3595 // one of the latter hops is limited.
3596 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3597 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3598 let scorer = test_utils::TestScorer::with_penalty(0);
3599 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3600 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3601 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3603 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3604 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3605 // Total capacity: 50 sats.
3607 // Disable other potential paths.
3608 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3609 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3610 short_channel_id: 2,
3613 cltv_expiry_delta: 0,
3614 htlc_minimum_msat: 0,
3615 htlc_maximum_msat: OptionalField::Present(100_000),
3617 fee_proportional_millionths: 0,
3618 excess_data: Vec::new()
3620 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3621 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3622 short_channel_id: 7,
3625 cltv_expiry_delta: 0,
3626 htlc_minimum_msat: 0,
3627 htlc_maximum_msat: OptionalField::Present(100_000),
3629 fee_proportional_millionths: 0,
3630 excess_data: Vec::new()
3635 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3636 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3637 short_channel_id: 12,
3640 cltv_expiry_delta: 0,
3641 htlc_minimum_msat: 0,
3642 htlc_maximum_msat: OptionalField::Present(100_000),
3644 fee_proportional_millionths: 0,
3645 excess_data: Vec::new()
3647 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3648 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3649 short_channel_id: 13,
3652 cltv_expiry_delta: 0,
3653 htlc_minimum_msat: 0,
3654 htlc_maximum_msat: OptionalField::Present(100_000),
3656 fee_proportional_millionths: 0,
3657 excess_data: Vec::new()
3660 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3661 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3662 short_channel_id: 6,
3665 cltv_expiry_delta: 0,
3666 htlc_minimum_msat: 0,
3667 htlc_maximum_msat: OptionalField::Present(50_000),
3669 fee_proportional_millionths: 0,
3670 excess_data: Vec::new()
3672 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3673 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3674 short_channel_id: 11,
3677 cltv_expiry_delta: 0,
3678 htlc_minimum_msat: 0,
3679 htlc_maximum_msat: OptionalField::Present(100_000),
3681 fee_proportional_millionths: 0,
3682 excess_data: Vec::new()
3685 // Attempt to route more than available results in a failure.
3686 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3687 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3688 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3689 } else { panic!(); }
3693 // Now, attempt to route 49 sats (just a bit below the capacity).
3694 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3695 assert_eq!(route.paths.len(), 1);
3696 let mut total_amount_paid_msat = 0;
3697 for path in &route.paths {
3698 assert_eq!(path.len(), 4);
3699 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3700 total_amount_paid_msat += path.last().unwrap().fee_msat;
3702 assert_eq!(total_amount_paid_msat, 49_000);
3706 // Attempt to route an exact amount is also fine
3707 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3708 assert_eq!(route.paths.len(), 1);
3709 let mut total_amount_paid_msat = 0;
3710 for path in &route.paths {
3711 assert_eq!(path.len(), 4);
3712 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3713 total_amount_paid_msat += path.last().unwrap().fee_msat;
3715 assert_eq!(total_amount_paid_msat, 50_000);
3720 fn ignore_fee_first_hop_test() {
3721 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3722 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3723 let scorer = test_utils::TestScorer::with_penalty(0);
3724 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3725 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3726 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3728 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3729 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3730 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3731 short_channel_id: 1,
3734 cltv_expiry_delta: 0,
3735 htlc_minimum_msat: 0,
3736 htlc_maximum_msat: OptionalField::Present(100_000),
3737 fee_base_msat: 1_000_000,
3738 fee_proportional_millionths: 0,
3739 excess_data: Vec::new()
3741 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3742 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3743 short_channel_id: 3,
3746 cltv_expiry_delta: 0,
3747 htlc_minimum_msat: 0,
3748 htlc_maximum_msat: OptionalField::Present(50_000),
3750 fee_proportional_millionths: 0,
3751 excess_data: Vec::new()
3755 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3756 assert_eq!(route.paths.len(), 1);
3757 let mut total_amount_paid_msat = 0;
3758 for path in &route.paths {
3759 assert_eq!(path.len(), 2);
3760 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3761 total_amount_paid_msat += path.last().unwrap().fee_msat;
3763 assert_eq!(total_amount_paid_msat, 50_000);
3768 fn simple_mpp_route_test() {
3769 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3770 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3771 let scorer = test_utils::TestScorer::with_penalty(0);
3772 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3773 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3774 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
3776 // We need a route consisting of 3 paths:
3777 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3778 // To achieve this, the amount being transferred should be around
3779 // the total capacity of these 3 paths.
3781 // First, we set limits on these (previously unlimited) channels.
3782 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3784 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3785 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3786 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3787 short_channel_id: 1,
3790 cltv_expiry_delta: 0,
3791 htlc_minimum_msat: 0,
3792 htlc_maximum_msat: OptionalField::Present(100_000),
3794 fee_proportional_millionths: 0,
3795 excess_data: Vec::new()
3797 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3798 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3799 short_channel_id: 3,
3802 cltv_expiry_delta: 0,
3803 htlc_minimum_msat: 0,
3804 htlc_maximum_msat: OptionalField::Present(50_000),
3806 fee_proportional_millionths: 0,
3807 excess_data: Vec::new()
3810 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3811 // (total limit 60).
3812 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3813 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3814 short_channel_id: 12,
3817 cltv_expiry_delta: 0,
3818 htlc_minimum_msat: 0,
3819 htlc_maximum_msat: OptionalField::Present(60_000),
3821 fee_proportional_millionths: 0,
3822 excess_data: Vec::new()
3824 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3825 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3826 short_channel_id: 13,
3829 cltv_expiry_delta: 0,
3830 htlc_minimum_msat: 0,
3831 htlc_maximum_msat: OptionalField::Present(60_000),
3833 fee_proportional_millionths: 0,
3834 excess_data: Vec::new()
3837 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3838 // (total capacity 180 sats).
3839 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3840 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3841 short_channel_id: 2,
3844 cltv_expiry_delta: 0,
3845 htlc_minimum_msat: 0,
3846 htlc_maximum_msat: OptionalField::Present(200_000),
3848 fee_proportional_millionths: 0,
3849 excess_data: Vec::new()
3851 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3852 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3853 short_channel_id: 4,
3856 cltv_expiry_delta: 0,
3857 htlc_minimum_msat: 0,
3858 htlc_maximum_msat: OptionalField::Present(180_000),
3860 fee_proportional_millionths: 0,
3861 excess_data: Vec::new()
3865 // Attempt to route more than available results in a failure.
3866 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3867 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3868 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3869 } else { panic!(); }
3873 // Now, attempt to route 250 sats (just a bit below the capacity).
3874 // Our algorithm should provide us with these 3 paths.
3875 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3876 assert_eq!(route.paths.len(), 3);
3877 let mut total_amount_paid_msat = 0;
3878 for path in &route.paths {
3879 assert_eq!(path.len(), 2);
3880 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3881 total_amount_paid_msat += path.last().unwrap().fee_msat;
3883 assert_eq!(total_amount_paid_msat, 250_000);
3887 // Attempt to route an exact amount is also fine
3888 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3889 assert_eq!(route.paths.len(), 3);
3890 let mut total_amount_paid_msat = 0;
3891 for path in &route.paths {
3892 assert_eq!(path.len(), 2);
3893 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3894 total_amount_paid_msat += path.last().unwrap().fee_msat;
3896 assert_eq!(total_amount_paid_msat, 290_000);
3901 fn long_mpp_route_test() {
3902 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
3903 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3904 let scorer = test_utils::TestScorer::with_penalty(0);
3905 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3906 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3907 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
3909 // We need a route consisting of 3 paths:
3910 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3911 // Note that these paths overlap (channels 5, 12, 13).
3912 // We will route 300 sats.
3913 // Each path will have 100 sats capacity, those channels which
3914 // are used twice will have 200 sats capacity.
3916 // Disable other potential paths.
3917 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3918 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3919 short_channel_id: 2,
3922 cltv_expiry_delta: 0,
3923 htlc_minimum_msat: 0,
3924 htlc_maximum_msat: OptionalField::Present(100_000),
3926 fee_proportional_millionths: 0,
3927 excess_data: Vec::new()
3929 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3930 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3931 short_channel_id: 7,
3934 cltv_expiry_delta: 0,
3935 htlc_minimum_msat: 0,
3936 htlc_maximum_msat: OptionalField::Present(100_000),
3938 fee_proportional_millionths: 0,
3939 excess_data: Vec::new()
3942 // Path via {node0, node2} is channels {1, 3, 5}.
3943 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3944 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3945 short_channel_id: 1,
3948 cltv_expiry_delta: 0,
3949 htlc_minimum_msat: 0,
3950 htlc_maximum_msat: OptionalField::Present(100_000),
3952 fee_proportional_millionths: 0,
3953 excess_data: Vec::new()
3955 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3956 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3957 short_channel_id: 3,
3960 cltv_expiry_delta: 0,
3961 htlc_minimum_msat: 0,
3962 htlc_maximum_msat: OptionalField::Present(100_000),
3964 fee_proportional_millionths: 0,
3965 excess_data: Vec::new()
3968 // Capacity of 200 sats because this channel will be used by 3rd path as well.
3969 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
3970 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3971 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3972 short_channel_id: 5,
3975 cltv_expiry_delta: 0,
3976 htlc_minimum_msat: 0,
3977 htlc_maximum_msat: OptionalField::Present(200_000),
3979 fee_proportional_millionths: 0,
3980 excess_data: Vec::new()
3983 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3984 // Add 100 sats to the capacities of {12, 13}, because these channels
3985 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
3986 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3987 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3988 short_channel_id: 12,
3991 cltv_expiry_delta: 0,
3992 htlc_minimum_msat: 0,
3993 htlc_maximum_msat: OptionalField::Present(200_000),
3995 fee_proportional_millionths: 0,
3996 excess_data: Vec::new()
3998 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3999 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4000 short_channel_id: 13,
4003 cltv_expiry_delta: 0,
4004 htlc_minimum_msat: 0,
4005 htlc_maximum_msat: OptionalField::Present(200_000),
4007 fee_proportional_millionths: 0,
4008 excess_data: Vec::new()
4011 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4012 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4013 short_channel_id: 6,
4016 cltv_expiry_delta: 0,
4017 htlc_minimum_msat: 0,
4018 htlc_maximum_msat: OptionalField::Present(100_000),
4020 fee_proportional_millionths: 0,
4021 excess_data: Vec::new()
4023 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4024 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4025 short_channel_id: 11,
4028 cltv_expiry_delta: 0,
4029 htlc_minimum_msat: 0,
4030 htlc_maximum_msat: OptionalField::Present(100_000),
4032 fee_proportional_millionths: 0,
4033 excess_data: Vec::new()
4036 // Path via {node7, node2} is channels {12, 13, 5}.
4037 // We already limited them to 200 sats (they are used twice for 100 sats).
4038 // Nothing to do here.
4041 // Attempt to route more than available results in a failure.
4042 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4043 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4044 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4045 } else { panic!(); }
4049 // Now, attempt to route 300 sats (exact amount we can route).
4050 // Our algorithm should provide us with these 3 paths, 100 sats each.
4051 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4052 assert_eq!(route.paths.len(), 3);
4054 let mut total_amount_paid_msat = 0;
4055 for path in &route.paths {
4056 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4057 total_amount_paid_msat += path.last().unwrap().fee_msat;
4059 assert_eq!(total_amount_paid_msat, 300_000);
4065 fn mpp_cheaper_route_test() {
4066 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4067 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4068 let scorer = test_utils::TestScorer::with_penalty(0);
4069 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4070 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4071 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4073 // This test checks that if we have two cheaper paths and one more expensive path,
4074 // so that liquidity-wise any 2 of 3 combination is sufficient,
4075 // two cheaper paths will be taken.
4076 // These paths have equal available liquidity.
4078 // We need a combination of 3 paths:
4079 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4080 // Note that these paths overlap (channels 5, 12, 13).
4081 // Each path will have 100 sats capacity, those channels which
4082 // are used twice will have 200 sats capacity.
4084 // Disable other potential paths.
4085 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4086 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4087 short_channel_id: 2,
4090 cltv_expiry_delta: 0,
4091 htlc_minimum_msat: 0,
4092 htlc_maximum_msat: OptionalField::Present(100_000),
4094 fee_proportional_millionths: 0,
4095 excess_data: Vec::new()
4097 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4098 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4099 short_channel_id: 7,
4102 cltv_expiry_delta: 0,
4103 htlc_minimum_msat: 0,
4104 htlc_maximum_msat: OptionalField::Present(100_000),
4106 fee_proportional_millionths: 0,
4107 excess_data: Vec::new()
4110 // Path via {node0, node2} is channels {1, 3, 5}.
4111 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4112 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4113 short_channel_id: 1,
4116 cltv_expiry_delta: 0,
4117 htlc_minimum_msat: 0,
4118 htlc_maximum_msat: OptionalField::Present(100_000),
4120 fee_proportional_millionths: 0,
4121 excess_data: Vec::new()
4123 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4124 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4125 short_channel_id: 3,
4128 cltv_expiry_delta: 0,
4129 htlc_minimum_msat: 0,
4130 htlc_maximum_msat: OptionalField::Present(100_000),
4132 fee_proportional_millionths: 0,
4133 excess_data: Vec::new()
4136 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4137 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4138 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4139 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4140 short_channel_id: 5,
4143 cltv_expiry_delta: 0,
4144 htlc_minimum_msat: 0,
4145 htlc_maximum_msat: OptionalField::Present(200_000),
4147 fee_proportional_millionths: 0,
4148 excess_data: Vec::new()
4151 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4152 // Add 100 sats to the capacities of {12, 13}, because these channels
4153 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4154 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4155 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4156 short_channel_id: 12,
4159 cltv_expiry_delta: 0,
4160 htlc_minimum_msat: 0,
4161 htlc_maximum_msat: OptionalField::Present(200_000),
4163 fee_proportional_millionths: 0,
4164 excess_data: Vec::new()
4166 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4167 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4168 short_channel_id: 13,
4171 cltv_expiry_delta: 0,
4172 htlc_minimum_msat: 0,
4173 htlc_maximum_msat: OptionalField::Present(200_000),
4175 fee_proportional_millionths: 0,
4176 excess_data: Vec::new()
4179 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4180 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4181 short_channel_id: 6,
4184 cltv_expiry_delta: 0,
4185 htlc_minimum_msat: 0,
4186 htlc_maximum_msat: OptionalField::Present(100_000),
4187 fee_base_msat: 1_000,
4188 fee_proportional_millionths: 0,
4189 excess_data: Vec::new()
4191 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4192 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4193 short_channel_id: 11,
4196 cltv_expiry_delta: 0,
4197 htlc_minimum_msat: 0,
4198 htlc_maximum_msat: OptionalField::Present(100_000),
4200 fee_proportional_millionths: 0,
4201 excess_data: Vec::new()
4204 // Path via {node7, node2} is channels {12, 13, 5}.
4205 // We already limited them to 200 sats (they are used twice for 100 sats).
4206 // Nothing to do here.
4209 // Now, attempt to route 180 sats.
4210 // Our algorithm should provide us with these 2 paths.
4211 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4212 assert_eq!(route.paths.len(), 2);
4214 let mut total_value_transferred_msat = 0;
4215 let mut total_paid_msat = 0;
4216 for path in &route.paths {
4217 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4218 total_value_transferred_msat += path.last().unwrap().fee_msat;
4220 total_paid_msat += hop.fee_msat;
4223 // If we paid fee, this would be higher.
4224 assert_eq!(total_value_transferred_msat, 180_000);
4225 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4226 assert_eq!(total_fees_paid, 0);
4231 fn fees_on_mpp_route_test() {
4232 // This test makes sure that MPP algorithm properly takes into account
4233 // fees charged on the channels, by making the fees impactful:
4234 // if the fee is not properly accounted for, the behavior is different.
4235 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4236 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4237 let scorer = test_utils::TestScorer::with_penalty(0);
4238 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4239 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4240 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(InvoiceFeatures::known());
4242 // We need a route consisting of 2 paths:
4243 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4244 // We will route 200 sats, Each path will have 100 sats capacity.
4246 // This test is not particularly stable: e.g.,
4247 // there's a way to route via {node0, node2, node4}.
4248 // It works while pathfinding is deterministic, but can be broken otherwise.
4249 // It's fine to ignore this concern for now.
4251 // Disable other potential paths.
4252 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4253 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4254 short_channel_id: 2,
4257 cltv_expiry_delta: 0,
4258 htlc_minimum_msat: 0,
4259 htlc_maximum_msat: OptionalField::Present(100_000),
4261 fee_proportional_millionths: 0,
4262 excess_data: Vec::new()
4265 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4266 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4267 short_channel_id: 7,
4270 cltv_expiry_delta: 0,
4271 htlc_minimum_msat: 0,
4272 htlc_maximum_msat: OptionalField::Present(100_000),
4274 fee_proportional_millionths: 0,
4275 excess_data: Vec::new()
4278 // Path via {node0, node2} is channels {1, 3, 5}.
4279 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4280 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4281 short_channel_id: 1,
4284 cltv_expiry_delta: 0,
4285 htlc_minimum_msat: 0,
4286 htlc_maximum_msat: OptionalField::Present(100_000),
4288 fee_proportional_millionths: 0,
4289 excess_data: Vec::new()
4291 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4292 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4293 short_channel_id: 3,
4296 cltv_expiry_delta: 0,
4297 htlc_minimum_msat: 0,
4298 htlc_maximum_msat: OptionalField::Present(100_000),
4300 fee_proportional_millionths: 0,
4301 excess_data: Vec::new()
4304 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4305 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4306 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4307 short_channel_id: 5,
4310 cltv_expiry_delta: 0,
4311 htlc_minimum_msat: 0,
4312 htlc_maximum_msat: OptionalField::Present(100_000),
4314 fee_proportional_millionths: 0,
4315 excess_data: Vec::new()
4318 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4319 // All channels should be 100 sats capacity. But for the fee experiment,
4320 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4321 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4322 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4323 // so no matter how large are other channels,
4324 // the whole path will be limited by 100 sats with just these 2 conditions:
4325 // - channel 12 capacity is 250 sats
4326 // - fee for channel 6 is 150 sats
4327 // Let's test this by enforcing these 2 conditions and removing other limits.
4328 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4329 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4330 short_channel_id: 12,
4333 cltv_expiry_delta: 0,
4334 htlc_minimum_msat: 0,
4335 htlc_maximum_msat: OptionalField::Present(250_000),
4337 fee_proportional_millionths: 0,
4338 excess_data: Vec::new()
4340 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4341 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4342 short_channel_id: 13,
4345 cltv_expiry_delta: 0,
4346 htlc_minimum_msat: 0,
4347 htlc_maximum_msat: OptionalField::Absent,
4349 fee_proportional_millionths: 0,
4350 excess_data: Vec::new()
4353 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4354 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4355 short_channel_id: 6,
4358 cltv_expiry_delta: 0,
4359 htlc_minimum_msat: 0,
4360 htlc_maximum_msat: OptionalField::Absent,
4361 fee_base_msat: 150_000,
4362 fee_proportional_millionths: 0,
4363 excess_data: Vec::new()
4365 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4366 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4367 short_channel_id: 11,
4370 cltv_expiry_delta: 0,
4371 htlc_minimum_msat: 0,
4372 htlc_maximum_msat: OptionalField::Absent,
4374 fee_proportional_millionths: 0,
4375 excess_data: Vec::new()
4379 // Attempt to route more than available results in a failure.
4380 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4381 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4382 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4383 } else { panic!(); }
4387 // Now, attempt to route 200 sats (exact amount we can route).
4388 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4389 assert_eq!(route.paths.len(), 2);
4391 let mut total_amount_paid_msat = 0;
4392 for path in &route.paths {
4393 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4394 total_amount_paid_msat += path.last().unwrap().fee_msat;
4396 assert_eq!(total_amount_paid_msat, 200_000);
4397 assert_eq!(route.get_total_fees(), 150_000);
4402 fn mpp_with_last_hops() {
4403 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4404 // via a single last-hop route hint, we'd fail to route if we first collected routes
4405 // totaling close but not quite enough to fund the full payment.
4407 // This was because we considered last-hop hints to have exactly the sought payment amount
4408 // instead of the amount we were trying to collect, needlessly limiting our path searching
4409 // at the very first hop.
4411 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4412 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4413 // to only have the remaining to-collect amount in available liquidity.
4415 // This bug appeared in production in some specific channel configurations.
4416 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4417 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4418 let scorer = test_utils::TestScorer::with_penalty(0);
4419 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4420 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4421 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(InvoiceFeatures::known())
4422 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4423 src_node_id: nodes[2],
4424 short_channel_id: 42,
4425 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4426 cltv_expiry_delta: 42,
4427 htlc_minimum_msat: None,
4428 htlc_maximum_msat: None,
4431 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4432 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4433 // would first use the no-fee route and then fail to find a path along the second route as
4434 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4435 // under 5% of our payment amount.
4436 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4437 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4438 short_channel_id: 1,
4441 cltv_expiry_delta: (5 << 4) | 5,
4442 htlc_minimum_msat: 0,
4443 htlc_maximum_msat: OptionalField::Present(99_000),
4444 fee_base_msat: u32::max_value(),
4445 fee_proportional_millionths: u32::max_value(),
4446 excess_data: Vec::new()
4448 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4449 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4450 short_channel_id: 2,
4453 cltv_expiry_delta: (5 << 4) | 3,
4454 htlc_minimum_msat: 0,
4455 htlc_maximum_msat: OptionalField::Present(99_000),
4456 fee_base_msat: u32::max_value(),
4457 fee_proportional_millionths: u32::max_value(),
4458 excess_data: Vec::new()
4460 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4461 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4462 short_channel_id: 4,
4465 cltv_expiry_delta: (4 << 4) | 1,
4466 htlc_minimum_msat: 0,
4467 htlc_maximum_msat: OptionalField::Absent,
4469 fee_proportional_millionths: 0,
4470 excess_data: Vec::new()
4472 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4473 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4474 short_channel_id: 13,
4476 flags: 0|2, // Channel disabled
4477 cltv_expiry_delta: (13 << 4) | 1,
4478 htlc_minimum_msat: 0,
4479 htlc_maximum_msat: OptionalField::Absent,
4481 fee_proportional_millionths: 2000000,
4482 excess_data: Vec::new()
4485 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4487 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4488 assert_eq!(route.paths.len(), 2);
4489 // Paths are somewhat randomly ordered, but:
4490 // * the first is channel 2 (1 msat fee) -> channel 4 -> channel 42
4491 // * the second is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4492 assert_eq!(route.paths[0][0].short_channel_id, 2);
4493 assert_eq!(route.paths[0][0].fee_msat, 1);
4494 assert_eq!(route.paths[0][2].fee_msat, 1_000);
4495 assert_eq!(route.paths[1][0].short_channel_id, 1);
4496 assert_eq!(route.paths[1][0].fee_msat, 0);
4497 assert_eq!(route.paths[1][2].fee_msat, 99_000);
4498 assert_eq!(route.get_total_fees(), 1);
4499 assert_eq!(route.get_total_amount(), 100_000);
4503 fn drop_lowest_channel_mpp_route_test() {
4504 // This test checks that low-capacity channel is dropped when after
4505 // path finding we realize that we found more capacity than we need.
4506 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4507 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4508 let scorer = test_utils::TestScorer::with_penalty(0);
4509 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4510 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4511 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4513 // We need a route consisting of 3 paths:
4514 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4516 // The first and the second paths should be sufficient, but the third should be
4517 // cheaper, so that we select it but drop later.
4519 // First, we set limits on these (previously unlimited) channels.
4520 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4522 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4523 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4524 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4525 short_channel_id: 1,
4528 cltv_expiry_delta: 0,
4529 htlc_minimum_msat: 0,
4530 htlc_maximum_msat: OptionalField::Present(100_000),
4532 fee_proportional_millionths: 0,
4533 excess_data: Vec::new()
4535 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4536 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4537 short_channel_id: 3,
4540 cltv_expiry_delta: 0,
4541 htlc_minimum_msat: 0,
4542 htlc_maximum_msat: OptionalField::Present(50_000),
4544 fee_proportional_millionths: 0,
4545 excess_data: Vec::new()
4548 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4549 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4550 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4551 short_channel_id: 12,
4554 cltv_expiry_delta: 0,
4555 htlc_minimum_msat: 0,
4556 htlc_maximum_msat: OptionalField::Present(60_000),
4558 fee_proportional_millionths: 0,
4559 excess_data: Vec::new()
4561 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4562 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4563 short_channel_id: 13,
4566 cltv_expiry_delta: 0,
4567 htlc_minimum_msat: 0,
4568 htlc_maximum_msat: OptionalField::Present(60_000),
4570 fee_proportional_millionths: 0,
4571 excess_data: Vec::new()
4574 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4575 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4576 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4577 short_channel_id: 2,
4580 cltv_expiry_delta: 0,
4581 htlc_minimum_msat: 0,
4582 htlc_maximum_msat: OptionalField::Present(20_000),
4584 fee_proportional_millionths: 0,
4585 excess_data: Vec::new()
4587 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4588 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4589 short_channel_id: 4,
4592 cltv_expiry_delta: 0,
4593 htlc_minimum_msat: 0,
4594 htlc_maximum_msat: OptionalField::Present(20_000),
4596 fee_proportional_millionths: 0,
4597 excess_data: Vec::new()
4601 // Attempt to route more than available results in a failure.
4602 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4603 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4604 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4605 } else { panic!(); }
4609 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4610 // Our algorithm should provide us with these 3 paths.
4611 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4612 assert_eq!(route.paths.len(), 3);
4613 let mut total_amount_paid_msat = 0;
4614 for path in &route.paths {
4615 assert_eq!(path.len(), 2);
4616 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4617 total_amount_paid_msat += path.last().unwrap().fee_msat;
4619 assert_eq!(total_amount_paid_msat, 125_000);
4623 // Attempt to route without the last small cheap channel
4624 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4625 assert_eq!(route.paths.len(), 2);
4626 let mut total_amount_paid_msat = 0;
4627 for path in &route.paths {
4628 assert_eq!(path.len(), 2);
4629 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4630 total_amount_paid_msat += path.last().unwrap().fee_msat;
4632 assert_eq!(total_amount_paid_msat, 90_000);
4637 fn min_criteria_consistency() {
4638 // Test that we don't use an inconsistent metric between updating and walking nodes during
4639 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4640 // was updated with a different criterion from the heap sorting, resulting in loops in
4641 // calculated paths. We test for that specific case here.
4643 // We construct a network that looks like this:
4645 // node2 -1(3)2- node3
4649 // node1 -1(5)2- node4 -1(1)2- node6
4655 // We create a loop on the side of our real path - our destination is node 6, with a
4656 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4657 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4658 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4659 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4660 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4661 // "previous hop" being set to node 3, creating a loop in the path.
4662 let secp_ctx = Secp256k1::new();
4663 let logger = Arc::new(test_utils::TestLogger::new());
4664 let network = Arc::new(NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash()));
4665 let net_graph_msg_handler = NetGraphMsgHandler::new(Arc::clone(&network), None, Arc::clone(&logger));
4666 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4667 let scorer = test_utils::TestScorer::with_penalty(0);
4668 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4669 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4670 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4672 add_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4673 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4674 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4675 short_channel_id: 6,
4678 cltv_expiry_delta: (6 << 4) | 0,
4679 htlc_minimum_msat: 0,
4680 htlc_maximum_msat: OptionalField::Absent,
4682 fee_proportional_millionths: 0,
4683 excess_data: Vec::new()
4685 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4687 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4688 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4689 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4690 short_channel_id: 5,
4693 cltv_expiry_delta: (5 << 4) | 0,
4694 htlc_minimum_msat: 0,
4695 htlc_maximum_msat: OptionalField::Absent,
4697 fee_proportional_millionths: 0,
4698 excess_data: Vec::new()
4700 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4702 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4703 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4704 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4705 short_channel_id: 4,
4708 cltv_expiry_delta: (4 << 4) | 0,
4709 htlc_minimum_msat: 0,
4710 htlc_maximum_msat: OptionalField::Absent,
4712 fee_proportional_millionths: 0,
4713 excess_data: Vec::new()
4715 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4717 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4718 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4719 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4720 short_channel_id: 3,
4723 cltv_expiry_delta: (3 << 4) | 0,
4724 htlc_minimum_msat: 0,
4725 htlc_maximum_msat: OptionalField::Absent,
4727 fee_proportional_millionths: 0,
4728 excess_data: Vec::new()
4730 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4732 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4733 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4734 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4735 short_channel_id: 2,
4738 cltv_expiry_delta: (2 << 4) | 0,
4739 htlc_minimum_msat: 0,
4740 htlc_maximum_msat: OptionalField::Absent,
4742 fee_proportional_millionths: 0,
4743 excess_data: Vec::new()
4746 add_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4747 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4748 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4749 short_channel_id: 1,
4752 cltv_expiry_delta: (1 << 4) | 0,
4753 htlc_minimum_msat: 100,
4754 htlc_maximum_msat: OptionalField::Absent,
4756 fee_proportional_millionths: 0,
4757 excess_data: Vec::new()
4759 add_or_update_node(&net_graph_msg_handler, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4762 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4763 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4764 assert_eq!(route.paths.len(), 1);
4765 assert_eq!(route.paths[0].len(), 3);
4767 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4768 assert_eq!(route.paths[0][0].short_channel_id, 6);
4769 assert_eq!(route.paths[0][0].fee_msat, 100);
4770 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4771 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4772 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4774 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4775 assert_eq!(route.paths[0][1].short_channel_id, 5);
4776 assert_eq!(route.paths[0][1].fee_msat, 0);
4777 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4778 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4779 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4781 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4782 assert_eq!(route.paths[0][2].short_channel_id, 1);
4783 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4784 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4785 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4786 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4792 fn exact_fee_liquidity_limit() {
4793 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4794 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4795 // we calculated fees on a higher value, resulting in us ignoring such paths.
4796 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4797 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4798 let scorer = test_utils::TestScorer::with_penalty(0);
4799 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4800 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4801 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4803 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4805 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4806 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4807 short_channel_id: 2,
4810 cltv_expiry_delta: 0,
4811 htlc_minimum_msat: 0,
4812 htlc_maximum_msat: OptionalField::Present(85_000),
4814 fee_proportional_millionths: 0,
4815 excess_data: Vec::new()
4818 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4819 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4820 short_channel_id: 12,
4823 cltv_expiry_delta: (4 << 4) | 1,
4824 htlc_minimum_msat: 0,
4825 htlc_maximum_msat: OptionalField::Present(270_000),
4827 fee_proportional_millionths: 1000000,
4828 excess_data: Vec::new()
4832 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4833 // 200% fee charged channel 13 in the 1-to-2 direction.
4834 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4835 assert_eq!(route.paths.len(), 1);
4836 assert_eq!(route.paths[0].len(), 2);
4838 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4839 assert_eq!(route.paths[0][0].short_channel_id, 12);
4840 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4841 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4842 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4843 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4845 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4846 assert_eq!(route.paths[0][1].short_channel_id, 13);
4847 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4848 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4849 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4850 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4855 fn htlc_max_reduction_below_min() {
4856 // Test that if, while walking the graph, we reduce the value being sent to meet an
4857 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4858 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4859 // resulting in us thinking there is no possible path, even if other paths exist.
4860 let (secp_ctx, network_graph, net_graph_msg_handler, _, logger) = build_graph();
4861 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4862 let scorer = test_utils::TestScorer::with_penalty(0);
4863 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4864 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4865 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(InvoiceFeatures::known());
4867 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4868 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4869 // then try to send 90_000.
4870 update_channel(&net_graph_msg_handler, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4871 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4872 short_channel_id: 2,
4875 cltv_expiry_delta: 0,
4876 htlc_minimum_msat: 0,
4877 htlc_maximum_msat: OptionalField::Present(80_000),
4879 fee_proportional_millionths: 0,
4880 excess_data: Vec::new()
4882 update_channel(&net_graph_msg_handler, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4883 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4884 short_channel_id: 4,
4887 cltv_expiry_delta: (4 << 4) | 1,
4888 htlc_minimum_msat: 90_000,
4889 htlc_maximum_msat: OptionalField::Absent,
4891 fee_proportional_millionths: 0,
4892 excess_data: Vec::new()
4896 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4897 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4898 // expensive) channels 12-13 path.
4899 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4900 assert_eq!(route.paths.len(), 1);
4901 assert_eq!(route.paths[0].len(), 2);
4903 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4904 assert_eq!(route.paths[0][0].short_channel_id, 12);
4905 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4906 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4907 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4908 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4910 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4911 assert_eq!(route.paths[0][1].short_channel_id, 13);
4912 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4913 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4914 assert_eq!(route.paths[0][1].node_features.le_flags(), InvoiceFeatures::known().le_flags());
4915 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4920 fn multiple_direct_first_hops() {
4921 // Previously we'd only ever considered one first hop path per counterparty.
4922 // However, as we don't restrict users to one channel per peer, we really need to support
4923 // looking at all first hop paths.
4924 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4925 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4926 // route over multiple channels with the same first hop.
4927 let secp_ctx = Secp256k1::new();
4928 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4929 let logger = Arc::new(test_utils::TestLogger::new());
4930 let network_graph = NetworkGraph::new(genesis_block(Network::Testnet).header.block_hash());
4931 let scorer = test_utils::TestScorer::with_penalty(0);
4932 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(InvoiceFeatures::known());
4933 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4934 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4937 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4938 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 200_000),
4939 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 10_000),
4940 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4941 assert_eq!(route.paths.len(), 1);
4942 assert_eq!(route.paths[0].len(), 1);
4944 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4945 assert_eq!(route.paths[0][0].short_channel_id, 3);
4946 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4949 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4950 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4951 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4952 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4953 assert_eq!(route.paths.len(), 2);
4954 assert_eq!(route.paths[0].len(), 1);
4955 assert_eq!(route.paths[1].len(), 1);
4957 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4958 assert_eq!(route.paths[0][0].short_channel_id, 3);
4959 assert_eq!(route.paths[0][0].fee_msat, 50_000);
4961 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
4962 assert_eq!(route.paths[1][0].short_channel_id, 2);
4963 assert_eq!(route.paths[1][0].fee_msat, 50_000);
4967 // If we have a bunch of outbound channels to the same node, where most are not
4968 // sufficient to pay the full payment, but one is, we should default to just using the
4969 // one single channel that has sufficient balance, avoiding MPP.
4971 // If we have several options above the 3xpayment value threshold, we should pick the
4972 // smallest of them, avoiding further fragmenting our available outbound balance to
4974 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
4975 &get_channel_details(Some(2), nodes[0], InitFeatures::known(), 50_000),
4976 &get_channel_details(Some(3), nodes[0], InitFeatures::known(), 50_000),
4977 &get_channel_details(Some(5), nodes[0], InitFeatures::known(), 50_000),
4978 &get_channel_details(Some(6), nodes[0], InitFeatures::known(), 300_000),
4979 &get_channel_details(Some(7), nodes[0], InitFeatures::known(), 50_000),
4980 &get_channel_details(Some(8), nodes[0], InitFeatures::known(), 50_000),
4981 &get_channel_details(Some(9), nodes[0], InitFeatures::known(), 50_000),
4982 &get_channel_details(Some(4), nodes[0], InitFeatures::known(), 1_000_000),
4983 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4984 assert_eq!(route.paths.len(), 1);
4985 assert_eq!(route.paths[0].len(), 1);
4987 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
4988 assert_eq!(route.paths[0][0].short_channel_id, 6);
4989 assert_eq!(route.paths[0][0].fee_msat, 100_000);
4994 fn prefers_shorter_route_with_higher_fees() {
4995 let (secp_ctx, network_graph, _, _, logger) = build_graph();
4996 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4997 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
4999 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5000 let scorer = test_utils::TestScorer::with_penalty(0);
5001 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5002 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5003 let route = get_route(
5004 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5005 Arc::clone(&logger), &scorer, &random_seed_bytes
5007 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5009 assert_eq!(route.get_total_fees(), 100);
5010 assert_eq!(route.get_total_amount(), 100);
5011 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5013 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5014 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5015 let scorer = test_utils::TestScorer::with_penalty(100);
5016 let route = get_route(
5017 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5018 Arc::clone(&logger), &scorer, &random_seed_bytes
5020 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5022 assert_eq!(route.get_total_fees(), 300);
5023 assert_eq!(route.get_total_amount(), 100);
5024 assert_eq!(path, vec![2, 4, 7, 10]);
5027 struct BadChannelScorer {
5028 short_channel_id: u64,
5032 impl Writeable for BadChannelScorer {
5033 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5035 impl Score for BadChannelScorer {
5036 fn channel_penalty_msat(&self, short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, _target: &NodeId) -> u64 {
5037 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5040 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5041 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5044 struct BadNodeScorer {
5049 impl Writeable for BadNodeScorer {
5050 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), ::io::Error> { unimplemented!() }
5053 impl Score for BadNodeScorer {
5054 fn channel_penalty_msat(&self, _short_channel_id: u64, _send_amt: u64, _capacity_msat: u64, _source: &NodeId, target: &NodeId) -> u64 {
5055 if *target == self.node_id { u64::max_value() } else { 0 }
5058 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5059 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5063 fn avoids_routing_through_bad_channels_and_nodes() {
5064 let (secp_ctx, network, _, _, logger) = build_graph();
5065 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5066 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5067 let network_graph = network.read_only();
5069 // A path to nodes[6] exists when no penalties are applied to any channel.
5070 let scorer = test_utils::TestScorer::with_penalty(0);
5071 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5072 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5073 let route = get_route(
5074 &our_id, &payment_params, &network_graph, None, 100, 42,
5075 Arc::clone(&logger), &scorer, &random_seed_bytes
5077 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5079 assert_eq!(route.get_total_fees(), 100);
5080 assert_eq!(route.get_total_amount(), 100);
5081 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5083 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5084 let scorer = BadChannelScorer { short_channel_id: 6 };
5085 let route = get_route(
5086 &our_id, &payment_params, &network_graph, None, 100, 42,
5087 Arc::clone(&logger), &scorer, &random_seed_bytes
5089 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5091 assert_eq!(route.get_total_fees(), 300);
5092 assert_eq!(route.get_total_amount(), 100);
5093 assert_eq!(path, vec![2, 4, 7, 10]);
5095 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5096 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5098 &our_id, &payment_params, &network_graph, None, 100, 42,
5099 Arc::clone(&logger), &scorer, &random_seed_bytes
5101 Err(LightningError { err, .. } ) => {
5102 assert_eq!(err, "Failed to find a path to the given destination");
5104 Ok(_) => panic!("Expected error"),
5109 fn total_fees_single_path() {
5113 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5114 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5115 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5118 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5119 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5120 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5123 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5124 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5125 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5128 payment_params: None,
5131 assert_eq!(route.get_total_fees(), 250);
5132 assert_eq!(route.get_total_amount(), 225);
5136 fn total_fees_multi_path() {
5140 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5141 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5142 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5145 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5146 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5147 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5151 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5152 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5153 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5156 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5157 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5158 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5161 payment_params: None,
5164 assert_eq!(route.get_total_fees(), 200);
5165 assert_eq!(route.get_total_amount(), 300);
5169 fn total_empty_route_no_panic() {
5170 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5171 // would both panic if the route was completely empty. We test to ensure they return 0
5172 // here, even though its somewhat nonsensical as a route.
5173 let route = Route { paths: Vec::new(), payment_params: None };
5175 assert_eq!(route.get_total_fees(), 0);
5176 assert_eq!(route.get_total_amount(), 0);
5180 fn limits_total_cltv_delta() {
5181 let (secp_ctx, network, _, _, logger) = build_graph();
5182 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5183 let network_graph = network.read_only();
5185 let scorer = test_utils::TestScorer::with_penalty(0);
5187 // Make sure that generally there is at least one route available
5188 let feasible_max_total_cltv_delta = 1008;
5189 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5190 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5191 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5192 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5193 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5194 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5195 assert_ne!(path.len(), 0);
5197 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5198 let fail_max_total_cltv_delta = 23;
5199 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5200 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5201 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5203 Err(LightningError { err, .. } ) => {
5204 assert_eq!(err, "Failed to find a path to the given destination");
5206 Ok(_) => panic!("Expected error"),
5211 fn adds_and_limits_cltv_offset() {
5212 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5213 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5215 let scorer = test_utils::TestScorer::with_penalty(0);
5217 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5218 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5219 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5220 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5221 assert_eq!(route.paths.len(), 1);
5223 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5225 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5226 let mut route_default = route.clone();
5227 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5228 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5229 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5230 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5231 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5233 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5234 let mut route_limited = route.clone();
5235 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5236 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5237 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5238 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5239 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5243 fn adds_plausible_cltv_offset() {
5244 let (secp_ctx, network, _, _, logger) = build_graph();
5245 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5246 let network_graph = network.read_only();
5247 let network_nodes = network_graph.nodes();
5248 let network_channels = network_graph.channels();
5249 let scorer = test_utils::TestScorer::with_penalty(0);
5250 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5251 let keys_manager = test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5252 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5254 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5255 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5256 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5258 let mut path_plausibility = vec![];
5260 for p in route.paths {
5261 // 1. Select random observation point
5262 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5263 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5265 prng.process_in_place(&mut random_bytes);
5266 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5267 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5269 // 2. Calculate what CLTV expiry delta we would observe there
5270 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5272 // 3. Starting from the observation point, find candidate paths
5273 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5274 candidates.push_back((observation_point, vec![]));
5276 let mut found_plausible_candidate = false;
5278 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5279 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5280 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5281 found_plausible_candidate = true;
5282 break 'candidate_loop;
5286 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5287 for channel_id in &cur_node.channels {
5288 if let Some(channel_info) = network_channels.get(&channel_id) {
5289 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5290 if let Some(channel_update_info) = dir_info.direction() {
5291 let next_cltv_expiry_delta = channel_update_info.cltv_expiry_delta as u32;
5292 if cur_path_cltv_deltas.iter().sum::<u32>()
5293 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5294 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5295 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5296 candidates.push_back((*next_id, new_path_cltv_deltas));
5305 path_plausibility.push(found_plausible_candidate);
5307 assert!(path_plausibility.iter().all(|x| *x));
5310 #[cfg(not(feature = "no-std"))]
5311 pub(super) fn random_init_seed() -> u64 {
5312 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5313 use core::hash::{BuildHasher, Hasher};
5314 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5315 println!("Using seed of {}", seed);
5318 #[cfg(not(feature = "no-std"))]
5319 use util::ser::Readable;
5322 #[cfg(not(feature = "no-std"))]
5323 fn generate_routes() {
5324 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5326 let mut d = match super::test_utils::get_route_file() {
5333 let graph = NetworkGraph::read(&mut d).unwrap();
5334 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5335 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5337 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5338 let mut seed = random_init_seed() as usize;
5339 let nodes = graph.read_only().nodes().clone();
5340 'load_endpoints: for _ in 0..10 {
5342 seed = seed.overflowing_mul(0xdeadbeef).0;
5343 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5344 seed = seed.overflowing_mul(0xdeadbeef).0;
5345 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5346 let payment_params = PaymentParameters::from_node_id(dst);
5347 let amt = seed as u64 % 200_000_000;
5348 let params = ProbabilisticScoringParameters::default();
5349 let scorer = ProbabilisticScorer::new(params, &graph);
5350 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5351 continue 'load_endpoints;
5358 #[cfg(not(feature = "no-std"))]
5359 fn generate_routes_mpp() {
5360 use routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5362 let mut d = match super::test_utils::get_route_file() {
5369 let graph = NetworkGraph::read(&mut d).unwrap();
5370 let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5371 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5373 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5374 let mut seed = random_init_seed() as usize;
5375 let nodes = graph.read_only().nodes().clone();
5376 'load_endpoints: for _ in 0..10 {
5378 seed = seed.overflowing_mul(0xdeadbeef).0;
5379 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5380 seed = seed.overflowing_mul(0xdeadbeef).0;
5381 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5382 let payment_params = PaymentParameters::from_node_id(dst).with_features(InvoiceFeatures::known());
5383 let amt = seed as u64 % 200_000_000;
5384 let params = ProbabilisticScoringParameters::default();
5385 let scorer = ProbabilisticScorer::new(params, &graph);
5386 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &test_utils::TestLogger::new(), &scorer, &random_seed_bytes).is_ok() {
5387 continue 'load_endpoints;
5394 #[cfg(all(test, not(feature = "no-std")))]
5395 pub(crate) mod test_utils {
5397 /// Tries to open a network graph file, or panics with a URL to fetch it.
5398 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5399 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5400 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5401 .or_else(|_| { // Fall back to guessing based on the binary location
5402 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5403 let mut path = std::env::current_exe().unwrap();
5404 path.pop(); // lightning-...
5406 path.pop(); // debug
5407 path.pop(); // target
5408 path.push("lightning");
5409 path.push("net_graph-2021-05-31.bin");
5410 eprintln!("{}", path.to_str().unwrap());
5413 .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");
5414 #[cfg(require_route_graph_test)]
5415 return Ok(res.unwrap());
5416 #[cfg(not(require_route_graph_test))]
5421 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5424 use bitcoin::hashes::Hash;
5425 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5426 use chain::transaction::OutPoint;
5427 use chain::keysinterface::{KeysManager,KeysInterface};
5428 use ln::channelmanager::{ChannelCounterparty, ChannelDetails};
5429 use ln::features::{InitFeatures, InvoiceFeatures};
5430 use routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters, Scorer};
5431 use util::logger::{Logger, Record};
5435 struct DummyLogger {}
5436 impl Logger for DummyLogger {
5437 fn log(&self, _record: &Record) {}
5440 fn read_network_graph() -> NetworkGraph {
5441 let mut d = test_utils::get_route_file().unwrap();
5442 NetworkGraph::read(&mut d).unwrap()
5445 fn payer_pubkey() -> PublicKey {
5446 let secp_ctx = Secp256k1::new();
5447 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5451 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5453 channel_id: [0; 32],
5454 counterparty: ChannelCounterparty {
5455 features: InitFeatures::known(),
5457 unspendable_punishment_reserve: 0,
5458 forwarding_info: None,
5460 funding_txo: Some(OutPoint {
5461 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5464 short_channel_id: Some(1),
5465 inbound_scid_alias: None,
5466 channel_value_satoshis: 10_000_000,
5468 balance_msat: 10_000_000,
5469 outbound_capacity_msat: 10_000_000,
5470 inbound_capacity_msat: 0,
5471 unspendable_punishment_reserve: None,
5472 confirmations_required: None,
5473 force_close_spend_delay: None,
5475 is_funding_locked: true,
5482 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5483 let network_graph = read_network_graph();
5484 let scorer = FixedPenaltyScorer::with_penalty(0);
5485 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5489 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5490 let network_graph = read_network_graph();
5491 let scorer = FixedPenaltyScorer::with_penalty(0);
5492 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5496 fn generate_routes_with_default_scorer(bench: &mut Bencher) {
5497 let network_graph = read_network_graph();
5498 let scorer = Scorer::default();
5499 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5503 fn generate_mpp_routes_with_default_scorer(bench: &mut Bencher) {
5504 let network_graph = read_network_graph();
5505 let scorer = Scorer::default();
5506 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5510 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5511 let network_graph = read_network_graph();
5512 let params = ProbabilisticScoringParameters::default();
5513 let scorer = ProbabilisticScorer::new(params, &network_graph);
5514 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5518 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5519 let network_graph = read_network_graph();
5520 let params = ProbabilisticScoringParameters::default();
5521 let scorer = ProbabilisticScorer::new(params, &network_graph);
5522 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::known());
5525 fn generate_routes<S: Score>(
5526 bench: &mut Bencher, graph: &NetworkGraph, mut scorer: S, features: InvoiceFeatures
5528 let nodes = graph.read_only().nodes().clone();
5529 let payer = payer_pubkey();
5530 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5531 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5533 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5534 let mut routes = Vec::new();
5535 let mut route_endpoints = Vec::new();
5536 let mut seed: usize = 0xdeadbeef;
5537 'load_endpoints: for _ in 0..150 {
5540 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5542 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5543 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5544 let first_hop = first_hop(src);
5545 let amt = seed as u64 % 1_000_000;
5546 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5548 route_endpoints.push((first_hop, params, amt));
5549 continue 'load_endpoints;
5554 // ...and seed the scorer with success and failure data...
5555 for route in routes {
5556 let amount = route.get_total_amount();
5557 if amount < 250_000 {
5558 for path in route.paths {
5559 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5561 } else if amount > 750_000 {
5562 for path in route.paths {
5563 let short_channel_id = path[path.len() / 2].short_channel_id;
5564 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5569 // Because we've changed channel scores, its possible we'll take different routes to the
5570 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5571 // requires a too-high CLTV delta.
5572 route_endpoints.retain(|(first_hop, params, amt)| {
5573 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5575 route_endpoints.truncate(100);
5576 assert_eq!(route_endpoints.len(), 100);
5578 // ...then benchmark finding paths between the nodes we learned.
5581 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5582 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());