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 P2PGossipSync and use that as your RoutingMessageHandler and then
13 //! interrogate it to get routes for your own payments.
15 use bitcoin::secp256k1::PublicKey;
16 use bitcoin::hashes::Hash;
17 use bitcoin::hashes::sha256::Hash as Sha256;
19 use crate::ln::PaymentHash;
20 use crate::ln::channelmanager::{ChannelDetails, PaymentId};
21 use crate::ln::features::{ChannelFeatures, InvoiceFeatures, NodeFeatures};
22 use crate::ln::msgs::{DecodeError, ErrorAction, LightningError, MAX_VALUE_MSAT};
23 use crate::routing::gossip::{DirectedChannelInfo, EffectiveCapacity, ReadOnlyNetworkGraph, NetworkGraph, NodeId, RoutingFees};
24 use crate::routing::scoring::{ChannelUsage, LockableScore, Score};
25 use crate::util::ser::{Writeable, Readable, Writer};
26 use crate::util::logger::{Level, Logger};
27 use crate::util::chacha20::ChaCha20;
30 use crate::prelude::*;
31 use crate::sync::Mutex;
32 use alloc::collections::BinaryHeap;
36 /// A [`Router`] implemented using [`find_route`].
37 pub struct DefaultRouter<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> where
39 S::Target: for <'a> LockableScore<'a>,
43 random_seed_bytes: Mutex<[u8; 32]>,
47 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> DefaultRouter<G, L, S> where
49 S::Target: for <'a> LockableScore<'a>,
51 /// Creates a new router.
52 pub fn new(network_graph: G, logger: L, random_seed_bytes: [u8; 32], scorer: S) -> Self {
53 let random_seed_bytes = Mutex::new(random_seed_bytes);
54 Self { network_graph, logger, random_seed_bytes, scorer }
58 impl<G: Deref<Target = NetworkGraph<L>>, L: Deref, S: Deref> Router for DefaultRouter<G, L, S> where
60 S::Target: for <'a> LockableScore<'a>,
63 &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]>,
64 inflight_htlcs: InFlightHtlcs
65 ) -> Result<Route, LightningError> {
66 let random_seed_bytes = {
67 let mut locked_random_seed_bytes = self.random_seed_bytes.lock().unwrap();
68 *locked_random_seed_bytes = Sha256::hash(&*locked_random_seed_bytes).into_inner();
69 *locked_random_seed_bytes
73 payer, params, &self.network_graph, first_hops, &*self.logger,
74 &ScorerAccountingForInFlightHtlcs::new(&mut self.scorer.lock(), inflight_htlcs),
79 fn notify_payment_path_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
80 self.scorer.lock().payment_path_failed(path, short_channel_id);
83 fn notify_payment_path_successful(&self, path: &[&RouteHop]) {
84 self.scorer.lock().payment_path_successful(path);
87 fn notify_payment_probe_successful(&self, path: &[&RouteHop]) {
88 self.scorer.lock().probe_successful(path);
91 fn notify_payment_probe_failed(&self, path: &[&RouteHop], short_channel_id: u64) {
92 self.scorer.lock().probe_failed(path, short_channel_id);
96 /// A trait defining behavior for routing a payment.
98 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values.
100 &self, payer: &PublicKey, route_params: &RouteParameters,
101 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs
102 ) -> Result<Route, LightningError>;
103 /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values. Includes
104 /// `PaymentHash` and `PaymentId` to be able to correlate the request with a specific payment.
105 fn find_route_with_id(
106 &self, payer: &PublicKey, route_params: &RouteParameters,
107 first_hops: Option<&[&ChannelDetails]>, inflight_htlcs: InFlightHtlcs,
108 _payment_hash: PaymentHash, _payment_id: PaymentId
109 ) -> Result<Route, LightningError> {
110 self.find_route(payer, route_params, first_hops, inflight_htlcs)
112 /// Lets the router know that payment through a specific path has failed.
113 fn notify_payment_path_failed(&self, path: &[&RouteHop], short_channel_id: u64);
114 /// Lets the router know that payment through a specific path was successful.
115 fn notify_payment_path_successful(&self, path: &[&RouteHop]);
116 /// Lets the router know that a payment probe was successful.
117 fn notify_payment_probe_successful(&self, path: &[&RouteHop]);
118 /// Lets the router know that a payment probe failed.
119 fn notify_payment_probe_failed(&self, path: &[&RouteHop], short_channel_id: u64);
122 /// [`Score`] implementation that factors in in-flight HTLC liquidity.
124 /// Useful for custom [`Router`] implementations to wrap their [`Score`] on-the-fly when calling
127 /// [`Score`]: crate::routing::scoring::Score
128 pub struct ScorerAccountingForInFlightHtlcs<'a, S: Score> {
130 // Maps a channel's short channel id and its direction to the liquidity used up.
131 inflight_htlcs: InFlightHtlcs,
134 impl<'a, S: Score> ScorerAccountingForInFlightHtlcs<'a, S> {
135 /// Initialize a new `ScorerAccountingForInFlightHtlcs`.
136 pub fn new(scorer: &'a mut S, inflight_htlcs: InFlightHtlcs) -> Self {
137 ScorerAccountingForInFlightHtlcs {
145 impl<'a, S:Score> Writeable for ScorerAccountingForInFlightHtlcs<'a, S> {
146 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.scorer.write(writer) }
149 impl<'a, S: Score> Score for ScorerAccountingForInFlightHtlcs<'a, S> {
150 fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId, usage: ChannelUsage) -> u64 {
151 if let Some(used_liquidity) = self.inflight_htlcs.used_liquidity_msat(
152 source, target, short_channel_id
154 let usage = ChannelUsage {
155 inflight_htlc_msat: usage.inflight_htlc_msat + used_liquidity,
159 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
161 self.scorer.channel_penalty_msat(short_channel_id, source, target, usage)
165 fn payment_path_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
166 self.scorer.payment_path_failed(path, short_channel_id)
169 fn payment_path_successful(&mut self, path: &[&RouteHop]) {
170 self.scorer.payment_path_successful(path)
173 fn probe_failed(&mut self, path: &[&RouteHop], short_channel_id: u64) {
174 self.scorer.probe_failed(path, short_channel_id)
177 fn probe_successful(&mut self, path: &[&RouteHop]) {
178 self.scorer.probe_successful(path)
182 /// A data structure for tracking in-flight HTLCs. May be used during pathfinding to account for
183 /// in-use channel liquidity.
184 pub struct InFlightHtlcs(
185 // A map with liquidity value (in msat) keyed by a short channel id and the direction the HTLC
186 // is traveling in. The direction boolean is determined by checking if the HTLC source's public
187 // key is less than its destination. See `InFlightHtlcs::used_liquidity_msat` for more
189 HashMap<(u64, bool), u64>
193 /// Constructs an empty `InFlightHtlcs`.
194 pub fn new() -> Self { InFlightHtlcs(HashMap::new()) }
196 /// Takes in a path with payer's node id and adds the path's details to `InFlightHtlcs`.
197 pub fn process_path(&mut self, path: &[RouteHop], payer_node_id: PublicKey) {
198 if path.is_empty() { return };
199 // total_inflight_map needs to be direction-sensitive when keeping track of the HTLC value
200 // that is held up. However, the `hops` array, which is a path returned by `find_route` in
201 // the router excludes the payer node. In the following lines, the payer's information is
202 // hardcoded with an inflight value of 0 so that we can correctly represent the first hop
203 // in our sliding window of two.
204 let reversed_hops_with_payer = path.iter().rev().skip(1)
205 .map(|hop| hop.pubkey)
206 .chain(core::iter::once(payer_node_id));
207 let mut cumulative_msat = 0;
209 // Taking the reversed vector from above, we zip it with just the reversed hops list to
210 // work "backwards" of the given path, since the last hop's `fee_msat` actually represents
211 // the total amount sent.
212 for (next_hop, prev_hop) in path.iter().rev().zip(reversed_hops_with_payer) {
213 cumulative_msat += next_hop.fee_msat;
215 .entry((next_hop.short_channel_id, NodeId::from_pubkey(&prev_hop) < NodeId::from_pubkey(&next_hop.pubkey)))
216 .and_modify(|used_liquidity_msat| *used_liquidity_msat += cumulative_msat)
217 .or_insert(cumulative_msat);
221 /// Returns liquidity in msat given the public key of the HTLC source, target, and short channel
223 pub fn used_liquidity_msat(&self, source: &NodeId, target: &NodeId, channel_scid: u64) -> Option<u64> {
224 self.0.get(&(channel_scid, source < target)).map(|v| *v)
228 impl Writeable for InFlightHtlcs {
229 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> { self.0.write(writer) }
232 impl Readable for InFlightHtlcs {
233 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
234 let infight_map: HashMap<(u64, bool), u64> = Readable::read(reader)?;
235 Ok(Self(infight_map))
240 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
241 pub struct RouteHop {
242 /// The node_id of the node at this hop.
243 pub pubkey: PublicKey,
244 /// The node_announcement features of the node at this hop. For the last hop, these may be
245 /// amended to match the features present in the invoice this node generated.
246 pub node_features: NodeFeatures,
247 /// The channel that should be used from the previous hop to reach this node.
248 pub short_channel_id: u64,
249 /// The channel_announcement features of the channel that should be used from the previous hop
250 /// to reach this node.
251 pub channel_features: ChannelFeatures,
252 /// The fee taken on this hop (for paying for the use of the *next* channel in the path).
253 /// For the last hop, this should be the full value of the payment (might be more than
254 /// requested if we had to match htlc_minimum_msat).
256 /// The CLTV delta added for this hop. For the last hop, this should be the full CLTV value
257 /// expected at the destination, in excess of the current block height.
258 pub cltv_expiry_delta: u32,
261 impl_writeable_tlv_based!(RouteHop, {
262 (0, pubkey, required),
263 (2, node_features, required),
264 (4, short_channel_id, required),
265 (6, channel_features, required),
266 (8, fee_msat, required),
267 (10, cltv_expiry_delta, required),
270 /// A route directs a payment from the sender (us) to the recipient. If the recipient supports MPP,
271 /// it can take multiple paths. Each path is composed of one or more hops through the network.
272 #[derive(Clone, Hash, PartialEq, Eq)]
274 /// The list of routes taken for a single (potentially-)multi-part payment. The pubkey of the
275 /// last RouteHop in each path must be the same. Each entry represents a list of hops, NOT
276 /// INCLUDING our own, where the last hop is the destination. Thus, this must always be at
277 /// least length one. While the maximum length of any given path is variable, keeping the length
278 /// of any path less or equal to 19 should currently ensure it is viable.
279 pub paths: Vec<Vec<RouteHop>>,
280 /// The `payment_params` parameter passed to [`find_route`].
281 /// This is used by `ChannelManager` to track information which may be required for retries,
282 /// provided back to you via [`Event::PaymentPathFailed`].
284 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
285 pub payment_params: Option<PaymentParameters>,
288 pub(crate) trait RoutePath {
289 /// Gets the fees for a given path, excluding any excess paid to the recipient.
290 fn get_path_fees(&self) -> u64;
292 impl RoutePath for Vec<RouteHop> {
293 fn get_path_fees(&self) -> u64 {
294 // Do not count last hop of each path since that's the full value of the payment
295 self.split_last().map(|(_, path_prefix)| path_prefix).unwrap_or(&[])
296 .iter().map(|hop| &hop.fee_msat)
302 /// Returns the total amount of fees paid on this [`Route`].
304 /// This doesn't include any extra payment made to the recipient, which can happen in excess of
305 /// the amount passed to [`find_route`]'s `params.final_value_msat`.
306 pub fn get_total_fees(&self) -> u64 {
307 self.paths.iter().map(|path| path.get_path_fees()).sum()
310 /// Returns the total amount paid on this [`Route`], excluding the fees.
311 pub fn get_total_amount(&self) -> u64 {
312 return self.paths.iter()
313 .map(|path| path.split_last().map(|(hop, _)| hop.fee_msat).unwrap_or(0))
318 const SERIALIZATION_VERSION: u8 = 1;
319 const MIN_SERIALIZATION_VERSION: u8 = 1;
321 impl Writeable for Route {
322 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
323 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
324 (self.paths.len() as u64).write(writer)?;
325 for hops in self.paths.iter() {
326 (hops.len() as u8).write(writer)?;
327 for hop in hops.iter() {
331 write_tlv_fields!(writer, {
332 (1, self.payment_params, option),
338 impl Readable for Route {
339 fn read<R: io::Read>(reader: &mut R) -> Result<Route, DecodeError> {
340 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
341 let path_count: u64 = Readable::read(reader)?;
342 let mut paths = Vec::with_capacity(cmp::min(path_count, 128) as usize);
343 for _ in 0..path_count {
344 let hop_count: u8 = Readable::read(reader)?;
345 let mut hops = Vec::with_capacity(hop_count as usize);
346 for _ in 0..hop_count {
347 hops.push(Readable::read(reader)?);
351 let mut payment_params = None;
352 read_tlv_fields!(reader, {
353 (1, payment_params, option),
355 Ok(Route { paths, payment_params })
359 /// Parameters needed to find a [`Route`].
361 /// Passed to [`find_route`] and [`build_route_from_hops`], but also provided in
362 /// [`Event::PaymentPathFailed`] for retrying a failed payment path.
364 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
365 #[derive(Clone, Debug)]
366 pub struct RouteParameters {
367 /// The parameters of the failed payment path.
368 pub payment_params: PaymentParameters,
370 /// The amount in msats sent on the failed payment path.
371 pub final_value_msat: u64,
373 /// The CLTV on the final hop of the failed payment path.
374 pub final_cltv_expiry_delta: u32,
377 impl_writeable_tlv_based!(RouteParameters, {
378 (0, payment_params, required),
379 (2, final_value_msat, required),
380 (4, final_cltv_expiry_delta, required),
383 /// Maximum total CTLV difference we allow for a full payment path.
384 pub const DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA: u32 = 1008;
386 /// Maximum number of paths we allow an (MPP) payment to have.
387 // The default limit is currently set rather arbitrary - there aren't any real fundamental path-count
388 // limits, but for now more than 10 paths likely carries too much one-path failure.
389 pub const DEFAULT_MAX_PATH_COUNT: u8 = 10;
391 // The median hop CLTV expiry delta currently seen in the network.
392 const MEDIAN_HOP_CLTV_EXPIRY_DELTA: u32 = 40;
394 // During routing, we only consider paths shorter than our maximum length estimate.
395 // In the TLV onion format, there is no fixed maximum length, but the `hop_payloads`
396 // field is always 1300 bytes. As the `tlv_payload` for each hop may vary in length, we have to
397 // estimate how many hops the route may have so that it actually fits the `hop_payloads` field.
399 // We estimate 3+32 (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) +
400 // 2+8 (short_channel_id) = 61 bytes for each intermediate hop and 3+32
401 // (payload length and HMAC) + 2+8 (amt_to_forward) + 2+4 (outgoing_cltv_value) + 2+32+8
402 // (payment_secret and total_msat) = 93 bytes for the final hop.
403 // Since the length of the potentially included `payment_metadata` is unknown to us, we round
404 // down from (1300-93) / 61 = 19.78... to arrive at a conservative estimate of 19.
405 const MAX_PATH_LENGTH_ESTIMATE: u8 = 19;
407 /// The recipient of a payment.
408 #[derive(Clone, Debug, Hash, PartialEq, Eq)]
409 pub struct PaymentParameters {
410 /// The node id of the payee.
411 pub payee_pubkey: PublicKey,
413 /// Features supported by the payee.
415 /// May be set from the payee's invoice or via [`for_keysend`]. May be `None` if the invoice
416 /// does not contain any features.
418 /// [`for_keysend`]: Self::for_keysend
419 pub features: Option<InvoiceFeatures>,
421 /// Hints for routing to the payee, containing channels connecting the payee to public nodes.
422 pub route_hints: Vec<RouteHint>,
424 /// Expiration of a payment to the payee, in seconds relative to the UNIX epoch.
425 pub expiry_time: Option<u64>,
427 /// The maximum total CLTV delta we accept for the route.
428 /// Defaults to [`DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA`].
429 pub max_total_cltv_expiry_delta: u32,
431 /// The maximum number of paths that may be used by (MPP) payments.
432 /// Defaults to [`DEFAULT_MAX_PATH_COUNT`].
433 pub max_path_count: u8,
435 /// Selects the maximum share of a channel's total capacity which will be sent over a channel,
436 /// as a power of 1/2. A higher value prefers to send the payment using more MPP parts whereas
437 /// a lower value prefers to send larger MPP parts, potentially saturating channels and
438 /// increasing failure probability for those paths.
440 /// Note that this restriction will be relaxed during pathfinding after paths which meet this
441 /// restriction have been found. While paths which meet this criteria will be searched for, it
442 /// is ultimately up to the scorer to select them over other paths.
444 /// A value of 0 will allow payments up to and including a channel's total announced usable
445 /// capacity, a value of one will only use up to half its capacity, two 1/4, etc.
448 pub max_channel_saturation_power_of_half: u8,
450 /// A list of SCIDs which this payment was previously attempted over and which caused the
451 /// payment to fail. Future attempts for the same payment shouldn't be relayed through any of
453 pub previously_failed_channels: Vec<u64>,
456 impl_writeable_tlv_based!(PaymentParameters, {
457 (0, payee_pubkey, required),
458 (1, max_total_cltv_expiry_delta, (default_value, DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA)),
459 (2, features, option),
460 (3, max_path_count, (default_value, DEFAULT_MAX_PATH_COUNT)),
461 (4, route_hints, vec_type),
462 (5, max_channel_saturation_power_of_half, (default_value, 2)),
463 (6, expiry_time, option),
464 (7, previously_failed_channels, vec_type),
467 impl PaymentParameters {
468 /// Creates a payee with the node id of the given `pubkey`.
469 pub fn from_node_id(payee_pubkey: PublicKey) -> Self {
475 max_total_cltv_expiry_delta: DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA,
476 max_path_count: DEFAULT_MAX_PATH_COUNT,
477 max_channel_saturation_power_of_half: 2,
478 previously_failed_channels: Vec::new(),
482 /// Creates a payee with the node id of the given `pubkey` to use for keysend payments.
483 pub fn for_keysend(payee_pubkey: PublicKey) -> Self {
484 Self::from_node_id(payee_pubkey).with_features(InvoiceFeatures::for_keysend())
487 /// Includes the payee's features.
489 /// (C-not exported) since bindings don't support move semantics
490 pub fn with_features(self, features: InvoiceFeatures) -> Self {
491 Self { features: Some(features), ..self }
494 /// Includes hints for routing to the payee.
496 /// (C-not exported) since bindings don't support move semantics
497 pub fn with_route_hints(self, route_hints: Vec<RouteHint>) -> Self {
498 Self { route_hints, ..self }
501 /// Includes a payment expiration in seconds relative to the UNIX epoch.
503 /// (C-not exported) since bindings don't support move semantics
504 pub fn with_expiry_time(self, expiry_time: u64) -> Self {
505 Self { expiry_time: Some(expiry_time), ..self }
508 /// Includes a limit for the total CLTV expiry delta which is considered during routing
510 /// (C-not exported) since bindings don't support move semantics
511 pub fn with_max_total_cltv_expiry_delta(self, max_total_cltv_expiry_delta: u32) -> Self {
512 Self { max_total_cltv_expiry_delta, ..self }
515 /// Includes a limit for the maximum number of payment paths that may be used.
517 /// (C-not exported) since bindings don't support move semantics
518 pub fn with_max_path_count(self, max_path_count: u8) -> Self {
519 Self { max_path_count, ..self }
522 /// Includes a limit for the maximum number of payment paths that may be used.
524 /// (C-not exported) since bindings don't support move semantics
525 pub fn with_max_channel_saturation_power_of_half(self, max_channel_saturation_power_of_half: u8) -> Self {
526 Self { max_channel_saturation_power_of_half, ..self }
530 /// A list of hops along a payment path terminating with a channel to the recipient.
531 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
532 pub struct RouteHint(pub Vec<RouteHintHop>);
534 impl Writeable for RouteHint {
535 fn write<W: crate::util::ser::Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
536 (self.0.len() as u64).write(writer)?;
537 for hop in self.0.iter() {
544 impl Readable for RouteHint {
545 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
546 let hop_count: u64 = Readable::read(reader)?;
547 let mut hops = Vec::with_capacity(cmp::min(hop_count, 16) as usize);
548 for _ in 0..hop_count {
549 hops.push(Readable::read(reader)?);
555 /// A channel descriptor for a hop along a payment path.
556 #[derive(Clone, Debug, Hash, Eq, PartialEq)]
557 pub struct RouteHintHop {
558 /// The node_id of the non-target end of the route
559 pub src_node_id: PublicKey,
560 /// The short_channel_id of this channel
561 pub short_channel_id: u64,
562 /// The fees which must be paid to use this channel
563 pub fees: RoutingFees,
564 /// The difference in CLTV values between this node and the next node.
565 pub cltv_expiry_delta: u16,
566 /// The minimum value, in msat, which must be relayed to the next hop.
567 pub htlc_minimum_msat: Option<u64>,
568 /// The maximum value in msat available for routing with a single HTLC.
569 pub htlc_maximum_msat: Option<u64>,
572 impl_writeable_tlv_based!(RouteHintHop, {
573 (0, src_node_id, required),
574 (1, htlc_minimum_msat, option),
575 (2, short_channel_id, required),
576 (3, htlc_maximum_msat, option),
578 (6, cltv_expiry_delta, required),
581 #[derive(Eq, PartialEq)]
582 struct RouteGraphNode {
584 lowest_fee_to_peer_through_node: u64,
585 lowest_fee_to_node: u64,
586 total_cltv_delta: u32,
587 // The maximum value a yet-to-be-constructed payment path might flow through this node.
588 // This value is upper-bounded by us by:
589 // - how much is needed for a path being constructed
590 // - how much value can channels following this node (up to the destination) can contribute,
591 // considering their capacity and fees
592 value_contribution_msat: u64,
593 /// The effective htlc_minimum_msat at this hop. If a later hop on the path had a higher HTLC
594 /// minimum, we use it, plus the fees required at each earlier hop to meet it.
595 path_htlc_minimum_msat: u64,
596 /// All penalties incurred from this hop on the way to the destination, as calculated using
598 path_penalty_msat: u64,
599 /// The number of hops walked up to this node.
600 path_length_to_node: u8,
603 impl cmp::Ord for RouteGraphNode {
604 fn cmp(&self, other: &RouteGraphNode) -> cmp::Ordering {
605 let other_score = cmp::max(other.lowest_fee_to_peer_through_node, other.path_htlc_minimum_msat)
606 .saturating_add(other.path_penalty_msat);
607 let self_score = cmp::max(self.lowest_fee_to_peer_through_node, self.path_htlc_minimum_msat)
608 .saturating_add(self.path_penalty_msat);
609 other_score.cmp(&self_score).then_with(|| other.node_id.cmp(&self.node_id))
613 impl cmp::PartialOrd for RouteGraphNode {
614 fn partial_cmp(&self, other: &RouteGraphNode) -> Option<cmp::Ordering> {
615 Some(self.cmp(other))
619 /// A wrapper around the various hop representations.
621 /// Used to construct a [`PathBuildingHop`] and to estimate [`EffectiveCapacity`].
622 #[derive(Clone, Debug)]
623 enum CandidateRouteHop<'a> {
624 /// A hop from the payer, where the outbound liquidity is known.
626 details: &'a ChannelDetails,
628 /// A hop found in the [`ReadOnlyNetworkGraph`], where the channel capacity may be unknown.
630 info: DirectedChannelInfo<'a>,
631 short_channel_id: u64,
633 /// A hop to the payee found in the payment invoice, though not necessarily a direct channel.
635 hint: &'a RouteHintHop,
639 impl<'a> CandidateRouteHop<'a> {
640 fn short_channel_id(&self) -> u64 {
642 CandidateRouteHop::FirstHop { details } => details.get_outbound_payment_scid().unwrap(),
643 CandidateRouteHop::PublicHop { short_channel_id, .. } => *short_channel_id,
644 CandidateRouteHop::PrivateHop { hint } => hint.short_channel_id,
648 // NOTE: This may alloc memory so avoid calling it in a hot code path.
649 fn features(&self) -> ChannelFeatures {
651 CandidateRouteHop::FirstHop { details } => details.counterparty.features.to_context(),
652 CandidateRouteHop::PublicHop { info, .. } => info.channel().features.clone(),
653 CandidateRouteHop::PrivateHop { .. } => ChannelFeatures::empty(),
657 fn cltv_expiry_delta(&self) -> u32 {
659 CandidateRouteHop::FirstHop { .. } => 0,
660 CandidateRouteHop::PublicHop { info, .. } => info.direction().cltv_expiry_delta as u32,
661 CandidateRouteHop::PrivateHop { hint } => hint.cltv_expiry_delta as u32,
665 fn htlc_minimum_msat(&self) -> u64 {
667 CandidateRouteHop::FirstHop { .. } => 0,
668 CandidateRouteHop::PublicHop { info, .. } => info.direction().htlc_minimum_msat,
669 CandidateRouteHop::PrivateHop { hint } => hint.htlc_minimum_msat.unwrap_or(0),
673 fn fees(&self) -> RoutingFees {
675 CandidateRouteHop::FirstHop { .. } => RoutingFees {
676 base_msat: 0, proportional_millionths: 0,
678 CandidateRouteHop::PublicHop { info, .. } => info.direction().fees,
679 CandidateRouteHop::PrivateHop { hint } => hint.fees,
683 fn effective_capacity(&self) -> EffectiveCapacity {
685 CandidateRouteHop::FirstHop { details } => EffectiveCapacity::ExactLiquidity {
686 liquidity_msat: details.next_outbound_htlc_limit_msat,
688 CandidateRouteHop::PublicHop { info, .. } => info.effective_capacity(),
689 CandidateRouteHop::PrivateHop { .. } => EffectiveCapacity::Infinite,
695 fn max_htlc_from_capacity(capacity: EffectiveCapacity, max_channel_saturation_power_of_half: u8) -> u64 {
696 let saturation_shift: u32 = max_channel_saturation_power_of_half as u32;
698 EffectiveCapacity::ExactLiquidity { liquidity_msat } => liquidity_msat,
699 EffectiveCapacity::Infinite => u64::max_value(),
700 EffectiveCapacity::Unknown => EffectiveCapacity::Unknown.as_msat(),
701 EffectiveCapacity::MaximumHTLC { amount_msat } =>
702 amount_msat.checked_shr(saturation_shift).unwrap_or(0),
703 EffectiveCapacity::Total { capacity_msat, htlc_maximum_msat } =>
704 cmp::min(capacity_msat.checked_shr(saturation_shift).unwrap_or(0), htlc_maximum_msat),
708 fn iter_equal<I1: Iterator, I2: Iterator>(mut iter_a: I1, mut iter_b: I2)
709 -> bool where I1::Item: PartialEq<I2::Item> {
711 let a = iter_a.next();
712 let b = iter_b.next();
713 if a.is_none() && b.is_none() { return true; }
714 if a.is_none() || b.is_none() { return false; }
715 if a.unwrap().ne(&b.unwrap()) { return false; }
719 /// It's useful to keep track of the hops associated with the fees required to use them,
720 /// so that we can choose cheaper paths (as per Dijkstra's algorithm).
721 /// Fee values should be updated only in the context of the whole path, see update_value_and_recompute_fees.
722 /// These fee values are useful to choose hops as we traverse the graph "payee-to-payer".
724 struct PathBuildingHop<'a> {
725 // Note that this should be dropped in favor of loading it from CandidateRouteHop, but doing so
726 // is a larger refactor and will require careful performance analysis.
728 candidate: CandidateRouteHop<'a>,
731 /// Minimal fees required to route to the source node of the current hop via any of its inbound channels.
732 src_lowest_inbound_fees: RoutingFees,
733 /// All the fees paid *after* this channel on the way to the destination
734 next_hops_fee_msat: u64,
735 /// Fee paid for the use of the current channel (see candidate.fees()).
736 /// The value will be actually deducted from the counterparty balance on the previous link.
737 hop_use_fee_msat: u64,
738 /// Used to compare channels when choosing the for routing.
739 /// Includes paying for the use of a hop and the following hops, as well as
740 /// an estimated cost of reaching this hop.
741 /// Might get stale when fees are recomputed. Primarily for internal use.
743 /// A mirror of the same field in RouteGraphNode. Note that this is only used during the graph
744 /// walk and may be invalid thereafter.
745 path_htlc_minimum_msat: u64,
746 /// All penalties incurred from this channel on the way to the destination, as calculated using
748 path_penalty_msat: u64,
749 /// If we've already processed a node as the best node, we shouldn't process it again. Normally
750 /// we'd just ignore it if we did as all channels would have a higher new fee, but because we
751 /// may decrease the amounts in use as we walk the graph, the actual calculated fee may
752 /// decrease as well. Thus, we have to explicitly track which nodes have been processed and
753 /// avoid processing them again.
755 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
756 // In tests, we apply further sanity checks on cases where we skip nodes we already processed
757 // to ensure it is specifically in cases where the fee has gone down because of a decrease in
758 // value_contribution_msat, which requires tracking it here. See comments below where it is
759 // used for more info.
760 value_contribution_msat: u64,
763 impl<'a> core::fmt::Debug for PathBuildingHop<'a> {
764 fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
765 let mut debug_struct = f.debug_struct("PathBuildingHop");
767 .field("node_id", &self.node_id)
768 .field("short_channel_id", &self.candidate.short_channel_id())
769 .field("total_fee_msat", &self.total_fee_msat)
770 .field("next_hops_fee_msat", &self.next_hops_fee_msat)
771 .field("hop_use_fee_msat", &self.hop_use_fee_msat)
772 .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)))
773 .field("path_penalty_msat", &self.path_penalty_msat)
774 .field("path_htlc_minimum_msat", &self.path_htlc_minimum_msat)
775 .field("cltv_expiry_delta", &self.candidate.cltv_expiry_delta());
776 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
777 let debug_struct = debug_struct
778 .field("value_contribution_msat", &self.value_contribution_msat);
779 debug_struct.finish()
783 // Instantiated with a list of hops with correct data in them collected during path finding,
784 // an instance of this struct should be further modified only via given methods.
786 struct PaymentPath<'a> {
787 hops: Vec<(PathBuildingHop<'a>, NodeFeatures)>,
790 impl<'a> PaymentPath<'a> {
791 // TODO: Add a value_msat field to PaymentPath and use it instead of this function.
792 fn get_value_msat(&self) -> u64 {
793 self.hops.last().unwrap().0.fee_msat
796 fn get_path_penalty_msat(&self) -> u64 {
797 self.hops.first().map(|h| h.0.path_penalty_msat).unwrap_or(u64::max_value())
800 fn get_total_fee_paid_msat(&self) -> u64 {
801 if self.hops.len() < 1 {
805 // Can't use next_hops_fee_msat because it gets outdated.
806 for (i, (hop, _)) in self.hops.iter().enumerate() {
807 if i != self.hops.len() - 1 {
808 result += hop.fee_msat;
814 fn get_cost_msat(&self) -> u64 {
815 self.get_total_fee_paid_msat().saturating_add(self.get_path_penalty_msat())
818 // If the amount transferred by the path is updated, the fees should be adjusted. Any other way
819 // to change fees may result in an inconsistency.
821 // Sometimes we call this function right after constructing a path which is inconsistent in
822 // that it the value being transferred has decreased while we were doing path finding, leading
823 // to the fees being paid not lining up with the actual limits.
825 // Note that this function is not aware of the available_liquidity limit, and thus does not
826 // support increasing the value being transferred beyond what was selected during the initial
828 fn update_value_and_recompute_fees(&mut self, value_msat: u64) {
829 let mut total_fee_paid_msat = 0 as u64;
830 for i in (0..self.hops.len()).rev() {
831 let last_hop = i == self.hops.len() - 1;
833 // For non-last-hop, this value will represent the fees paid on the current hop. It
834 // will consist of the fees for the use of the next hop, and extra fees to match
835 // htlc_minimum_msat of the current channel. Last hop is handled separately.
836 let mut cur_hop_fees_msat = 0;
838 cur_hop_fees_msat = self.hops.get(i + 1).unwrap().0.hop_use_fee_msat;
841 let mut cur_hop = &mut self.hops.get_mut(i).unwrap().0;
842 cur_hop.next_hops_fee_msat = total_fee_paid_msat;
843 // Overpay in fees if we can't save these funds due to htlc_minimum_msat.
844 // We try to account for htlc_minimum_msat in scoring (add_entry!), so that nodes don't
845 // set it too high just to maliciously take more fees by exploiting this
846 // match htlc_minimum_msat logic.
847 let mut cur_hop_transferred_amount_msat = total_fee_paid_msat + value_msat;
848 if let Some(extra_fees_msat) = cur_hop.candidate.htlc_minimum_msat().checked_sub(cur_hop_transferred_amount_msat) {
849 // Note that there is a risk that *previous hops* (those closer to us, as we go
850 // payee->our_node here) would exceed their htlc_maximum_msat or available balance.
852 // This might make us end up with a broken route, although this should be super-rare
853 // in practice, both because of how healthy channels look like, and how we pick
854 // channels in add_entry.
855 // Also, this can't be exploited more heavily than *announce a free path and fail
857 cur_hop_transferred_amount_msat += extra_fees_msat;
858 total_fee_paid_msat += extra_fees_msat;
859 cur_hop_fees_msat += extra_fees_msat;
863 // Final hop is a special case: it usually has just value_msat (by design), but also
864 // it still could overpay for the htlc_minimum_msat.
865 cur_hop.fee_msat = cur_hop_transferred_amount_msat;
867 // Propagate updated fees for the use of the channels to one hop back, where they
868 // will be actually paid (fee_msat). The last hop is handled above separately.
869 cur_hop.fee_msat = cur_hop_fees_msat;
872 // Fee for the use of the current hop which will be deducted on the previous hop.
873 // Irrelevant for the first hop, as it doesn't have the previous hop, and the use of
874 // this channel is free for us.
876 if let Some(new_fee) = compute_fees(cur_hop_transferred_amount_msat, cur_hop.candidate.fees()) {
877 cur_hop.hop_use_fee_msat = new_fee;
878 total_fee_paid_msat += new_fee;
880 // It should not be possible because this function is called only to reduce the
881 // value. In that case, compute_fee was already called with the same fees for
882 // larger amount and there was no overflow.
890 fn compute_fees(amount_msat: u64, channel_fees: RoutingFees) -> Option<u64> {
891 let proportional_fee_millions =
892 amount_msat.checked_mul(channel_fees.proportional_millionths as u64);
893 if let Some(new_fee) = proportional_fee_millions.and_then(|part| {
894 (channel_fees.base_msat as u64).checked_add(part / 1_000_000) }) {
898 // This function may be (indirectly) called without any verification,
899 // with channel_fees provided by a caller. We should handle it gracefully.
904 /// The default `features` we assume for a node in a route, when no `features` are known about that
907 /// Default features are:
908 /// * variable_length_onion_optional
909 fn default_node_features() -> NodeFeatures {
910 let mut features = NodeFeatures::empty();
911 features.set_variable_length_onion_optional();
915 /// Finds a route from us (payer) to the given target node (payee).
917 /// If the payee provided features in their invoice, they should be provided via `params.payee`.
918 /// Without this, MPP will only be used if the payee's features are available in the network graph.
920 /// Private routing paths between a public node and the target may be included in `params.payee`.
922 /// If some channels aren't announced, it may be useful to fill in `first_hops` with the results
923 /// from [`ChannelManager::list_usable_channels`]. If it is filled in, the view of these channels
924 /// from `network_graph` will be ignored, and only those in `first_hops` will be used.
926 /// The fees on channels from us to the next hop are ignored as they are assumed to all be equal.
927 /// However, the enabled/disabled bit on such channels as well as the `htlc_minimum_msat` /
928 /// `htlc_maximum_msat` *are* checked as they may change based on the receiving node.
932 /// May be used to re-compute a [`Route`] when handling a [`Event::PaymentPathFailed`]. Any
933 /// adjustments to the [`NetworkGraph`] and channel scores should be made prior to calling this
938 /// Panics if first_hops contains channels without short_channel_ids;
939 /// [`ChannelManager::list_usable_channels`] will never include such channels.
941 /// [`ChannelManager::list_usable_channels`]: crate::ln::channelmanager::ChannelManager::list_usable_channels
942 /// [`Event::PaymentPathFailed`]: crate::util::events::Event::PaymentPathFailed
943 /// [`NetworkGraph`]: crate::routing::gossip::NetworkGraph
944 pub fn find_route<L: Deref, GL: Deref, S: Score>(
945 our_node_pubkey: &PublicKey, route_params: &RouteParameters,
946 network_graph: &NetworkGraph<GL>, first_hops: Option<&[&ChannelDetails]>, logger: L,
947 scorer: &S, random_seed_bytes: &[u8; 32]
948 ) -> Result<Route, LightningError>
949 where L::Target: Logger, GL::Target: Logger {
950 let graph_lock = network_graph.read_only();
951 let mut route = get_route(our_node_pubkey, &route_params.payment_params, &graph_lock, first_hops,
952 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, scorer,
954 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
958 pub(crate) fn get_route<L: Deref, S: Score>(
959 our_node_pubkey: &PublicKey, payment_params: &PaymentParameters, network_graph: &ReadOnlyNetworkGraph,
960 first_hops: Option<&[&ChannelDetails]>, final_value_msat: u64, final_cltv_expiry_delta: u32,
961 logger: L, scorer: &S, _random_seed_bytes: &[u8; 32]
962 ) -> Result<Route, LightningError>
963 where L::Target: Logger {
964 let payee_node_id = NodeId::from_pubkey(&payment_params.payee_pubkey);
965 let our_node_id = NodeId::from_pubkey(&our_node_pubkey);
967 if payee_node_id == our_node_id {
968 return Err(LightningError{err: "Cannot generate a route to ourselves".to_owned(), action: ErrorAction::IgnoreError});
971 if final_value_msat > MAX_VALUE_MSAT {
972 return Err(LightningError{err: "Cannot generate a route of more value than all existing satoshis".to_owned(), action: ErrorAction::IgnoreError});
975 if final_value_msat == 0 {
976 return Err(LightningError{err: "Cannot send a payment of 0 msat".to_owned(), action: ErrorAction::IgnoreError});
979 for route in payment_params.route_hints.iter() {
980 for hop in &route.0 {
981 if hop.src_node_id == payment_params.payee_pubkey {
982 return Err(LightningError{err: "Route hint cannot have the payee as the source.".to_owned(), action: ErrorAction::IgnoreError});
986 if payment_params.max_total_cltv_expiry_delta <= final_cltv_expiry_delta {
987 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});
990 // The general routing idea is the following:
991 // 1. Fill first/last hops communicated by the caller.
992 // 2. Attempt to construct a path from payer to payee for transferring
993 // any ~sufficient (described later) value.
994 // If succeed, remember which channels were used and how much liquidity they have available,
995 // so that future paths don't rely on the same liquidity.
996 // 3. Proceed to the next step if:
997 // - we hit the recommended target value;
998 // - OR if we could not construct a new path. Any next attempt will fail too.
999 // Otherwise, repeat step 2.
1000 // 4. See if we managed to collect paths which aggregately are able to transfer target value
1001 // (not recommended value).
1002 // 5. If yes, proceed. If not, fail routing.
1003 // 6. Select the paths which have the lowest cost (fee plus scorer penalty) per amount
1004 // transferred up to the transfer target value.
1005 // 7. Reduce the value of the last path until we are sending only the target value.
1006 // 8. If our maximum channel saturation limit caused us to pick two identical paths, combine
1007 // them so that we're not sending two HTLCs along the same path.
1009 // As for the actual search algorithm,
1010 // we do a payee-to-payer pseudo-Dijkstra's sorting by each node's distance from the payee
1011 // plus the minimum per-HTLC fee to get from it to another node (aka "shitty pseudo-A*").
1013 // We are not a faithful Dijkstra's implementation because we can change values which impact
1014 // earlier nodes while processing later nodes. Specifically, if we reach a channel with a lower
1015 // liquidity limit (via htlc_maximum_msat, on-chain capacity or assumed liquidity limits) than
1016 // the value we are currently attempting to send over a path, we simply reduce the value being
1017 // sent along the path for any hops after that channel. This may imply that later fees (which
1018 // we've already tabulated) are lower because a smaller value is passing through the channels
1019 // (and the proportional fee is thus lower). There isn't a trivial way to recalculate the
1020 // channels which were selected earlier (and which may still be used for other paths without a
1021 // lower liquidity limit), so we simply accept that some liquidity-limited paths may be
1024 // One potentially problematic case for this algorithm would be if there are many
1025 // liquidity-limited paths which are liquidity-limited near the destination (ie early in our
1026 // graph walking), we may never find a path which is not liquidity-limited and has lower
1027 // proportional fee (and only lower absolute fee when considering the ultimate value sent).
1028 // Because we only consider paths with at least 5% of the total value being sent, the damage
1029 // from such a case should be limited, however this could be further reduced in the future by
1030 // calculating fees on the amount we wish to route over a path, ie ignoring the liquidity
1031 // limits for the purposes of fee calculation.
1033 // Alternatively, we could store more detailed path information in the heap (targets, below)
1034 // and index the best-path map (dist, below) by node *and* HTLC limits, however that would blow
1035 // up the runtime significantly both algorithmically (as we'd traverse nodes multiple times)
1036 // and practically (as we would need to store dynamically-allocated path information in heap
1037 // objects, increasing malloc traffic and indirect memory access significantly). Further, the
1038 // results of such an algorithm would likely be biased towards lower-value paths.
1040 // Further, we could return to a faithful Dijkstra's algorithm by rejecting paths with limits
1041 // outside of our current search value, running a path search more times to gather candidate
1042 // paths at different values. While this may be acceptable, further path searches may increase
1043 // runtime for little gain. Specifically, the current algorithm rather efficiently explores the
1044 // graph for candidate paths, calculating the maximum value which can realistically be sent at
1045 // the same time, remaining generic across different payment values.
1047 // TODO: There are a few tweaks we could do, including possibly pre-calculating more stuff
1048 // to use as the A* heuristic beyond just the cost to get one node further than the current
1051 let network_channels = network_graph.channels();
1052 let network_nodes = network_graph.nodes();
1054 if payment_params.max_path_count == 0 {
1055 return Err(LightningError{err: "Can't find a route with no paths allowed.".to_owned(), action: ErrorAction::IgnoreError});
1058 // Allow MPP only if we have a features set from somewhere that indicates the payee supports
1059 // it. If the payee supports it they're supposed to include it in the invoice, so that should
1061 let allow_mpp = if payment_params.max_path_count == 1 {
1063 } else if let Some(features) = &payment_params.features {
1064 features.supports_basic_mpp()
1065 } else if let Some(node) = network_nodes.get(&payee_node_id) {
1066 if let Some(node_info) = node.announcement_info.as_ref() {
1067 node_info.features.supports_basic_mpp()
1071 log_trace!(logger, "Searching for a route from payer {} to payee {} {} MPP and {} first hops {}overriding the network graph", our_node_pubkey,
1072 payment_params.payee_pubkey, if allow_mpp { "with" } else { "without" },
1073 first_hops.map(|hops| hops.len()).unwrap_or(0), if first_hops.is_some() { "" } else { "not " });
1076 // Prepare the data we'll use for payee-to-payer search by
1077 // inserting first hops suggested by the caller as targets.
1078 // Our search will then attempt to reach them while traversing from the payee node.
1079 let mut first_hop_targets: HashMap<_, Vec<&ChannelDetails>> =
1080 HashMap::with_capacity(if first_hops.is_some() { first_hops.as_ref().unwrap().len() } else { 0 });
1081 if let Some(hops) = first_hops {
1083 if chan.get_outbound_payment_scid().is_none() {
1084 panic!("first_hops should be filled in with usable channels, not pending ones");
1086 if chan.counterparty.node_id == *our_node_pubkey {
1087 return Err(LightningError{err: "First hop cannot have our_node_pubkey as a destination.".to_owned(), action: ErrorAction::IgnoreError});
1090 .entry(NodeId::from_pubkey(&chan.counterparty.node_id))
1091 .or_insert(Vec::new())
1094 if first_hop_targets.is_empty() {
1095 return Err(LightningError{err: "Cannot route when there are no outbound routes away from us".to_owned(), action: ErrorAction::IgnoreError});
1099 // The main heap containing all candidate next-hops sorted by their score (max(A* fee,
1100 // htlc_minimum)). Ideally this would be a heap which allowed cheap score reduction instead of
1101 // adding duplicate entries when we find a better path to a given node.
1102 let mut targets: BinaryHeap<RouteGraphNode> = BinaryHeap::new();
1104 // Map from node_id to information about the best current path to that node, including feerate
1106 let mut dist: HashMap<NodeId, PathBuildingHop> = HashMap::with_capacity(network_nodes.len());
1108 // During routing, if we ignore a path due to an htlc_minimum_msat limit, we set this,
1109 // indicating that we may wish to try again with a higher value, potentially paying to meet an
1110 // htlc_minimum with extra fees while still finding a cheaper path.
1111 let mut hit_minimum_limit;
1113 // When arranging a route, we select multiple paths so that we can make a multi-path payment.
1114 // We start with a path_value of the exact amount we want, and if that generates a route we may
1115 // return it immediately. Otherwise, we don't stop searching for paths until we have 3x the
1116 // amount we want in total across paths, selecting the best subset at the end.
1117 const ROUTE_CAPACITY_PROVISION_FACTOR: u64 = 3;
1118 let recommended_value_msat = final_value_msat * ROUTE_CAPACITY_PROVISION_FACTOR as u64;
1119 let mut path_value_msat = final_value_msat;
1121 // Routing Fragmentation Mitigation heuristic:
1123 // Routing fragmentation across many payment paths increases the overall routing
1124 // fees as you have irreducible routing fees per-link used (`fee_base_msat`).
1125 // Taking too many smaller paths also increases the chance of payment failure.
1126 // Thus to avoid this effect, we require from our collected links to provide
1127 // at least a minimal contribution to the recommended value yet-to-be-fulfilled.
1128 // This requirement is currently set to be 1/max_path_count of the payment
1129 // value to ensure we only ever return routes that do not violate this limit.
1130 let minimal_value_contribution_msat: u64 = if allow_mpp {
1131 (final_value_msat + (payment_params.max_path_count as u64 - 1)) / payment_params.max_path_count as u64
1136 // When we start collecting routes we enforce the max_channel_saturation_power_of_half
1137 // requirement strictly. After we've collected enough (or if we fail to find new routes) we
1138 // drop the requirement by setting this to 0.
1139 let mut channel_saturation_pow_half = payment_params.max_channel_saturation_power_of_half;
1141 // Keep track of how much liquidity has been used in selected channels. Used to determine
1142 // if the channel can be used by additional MPP paths or to inform path finding decisions. It is
1143 // aware of direction *only* to ensure that the correct htlc_maximum_msat value is used. Hence,
1144 // liquidity used in one direction will not offset any used in the opposite direction.
1145 let mut used_channel_liquidities: HashMap<(u64, bool), u64> =
1146 HashMap::with_capacity(network_nodes.len());
1148 // Keeping track of how much value we already collected across other paths. Helps to decide
1149 // when we want to stop looking for new paths.
1150 let mut already_collected_value_msat = 0;
1152 for (_, channels) in first_hop_targets.iter_mut() {
1153 // Sort the first_hops channels to the same node(s) in priority order of which channel we'd
1154 // most like to use.
1156 // First, if channels are below `recommended_value_msat`, sort them in descending order,
1157 // preferring larger channels to avoid splitting the payment into more MPP parts than is
1160 // Second, because simply always sorting in descending order would always use our largest
1161 // available outbound capacity, needlessly fragmenting our available channel capacities,
1162 // sort channels above `recommended_value_msat` in ascending order, preferring channels
1163 // which have enough, but not too much, capacity for the payment.
1164 channels.sort_unstable_by(|chan_a, chan_b| {
1165 if chan_b.next_outbound_htlc_limit_msat < recommended_value_msat || chan_a.next_outbound_htlc_limit_msat < recommended_value_msat {
1166 // Sort in descending order
1167 chan_b.next_outbound_htlc_limit_msat.cmp(&chan_a.next_outbound_htlc_limit_msat)
1169 // Sort in ascending order
1170 chan_a.next_outbound_htlc_limit_msat.cmp(&chan_b.next_outbound_htlc_limit_msat)
1175 log_trace!(logger, "Building path from {} (payee) to {} (us/payer) for value {} msat.", payment_params.payee_pubkey, our_node_pubkey, final_value_msat);
1177 macro_rules! add_entry {
1178 // Adds entry which goes from $src_node_id to $dest_node_id over the $candidate hop.
1179 // $next_hops_fee_msat represents the fees paid for using all the channels *after* this one,
1180 // since that value has to be transferred over this channel.
1181 // Returns whether this channel caused an update to `targets`.
1182 ( $candidate: expr, $src_node_id: expr, $dest_node_id: expr, $next_hops_fee_msat: expr,
1183 $next_hops_value_contribution: expr, $next_hops_path_htlc_minimum_msat: expr,
1184 $next_hops_path_penalty_msat: expr, $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => { {
1185 // We "return" whether we updated the path at the end, via this:
1186 let mut did_add_update_path_to_src_node = false;
1187 // Channels to self should not be used. This is more of belt-and-suspenders, because in
1188 // practice these cases should be caught earlier:
1189 // - for regular channels at channel announcement (TODO)
1190 // - for first and last hops early in get_route
1191 if $src_node_id != $dest_node_id {
1192 let short_channel_id = $candidate.short_channel_id();
1193 let effective_capacity = $candidate.effective_capacity();
1194 let htlc_maximum_msat = max_htlc_from_capacity(effective_capacity, channel_saturation_pow_half);
1196 // It is tricky to subtract $next_hops_fee_msat from available liquidity here.
1197 // It may be misleading because we might later choose to reduce the value transferred
1198 // over these channels, and the channel which was insufficient might become sufficient.
1199 // Worst case: we drop a good channel here because it can't cover the high following
1200 // fees caused by one expensive channel, but then this channel could have been used
1201 // if the amount being transferred over this path is lower.
1202 // We do this for now, but this is a subject for removal.
1203 if let Some(mut available_value_contribution_msat) = htlc_maximum_msat.checked_sub($next_hops_fee_msat) {
1204 let used_liquidity_msat = used_channel_liquidities
1205 .get(&(short_channel_id, $src_node_id < $dest_node_id))
1206 .map_or(0, |used_liquidity_msat| {
1207 available_value_contribution_msat = available_value_contribution_msat
1208 .saturating_sub(*used_liquidity_msat);
1209 *used_liquidity_msat
1212 // Verify the liquidity offered by this channel complies to the minimal contribution.
1213 let contributes_sufficient_value = available_value_contribution_msat >= minimal_value_contribution_msat;
1214 // Do not consider candidate hops that would exceed the maximum path length.
1215 let path_length_to_node = $next_hops_path_length + 1;
1216 let exceeds_max_path_length = path_length_to_node > MAX_PATH_LENGTH_ESTIMATE;
1218 // Do not consider candidates that exceed the maximum total cltv expiry limit.
1219 // In order to already account for some of the privacy enhancing random CLTV
1220 // expiry delta offset we add on top later, we subtract a rough estimate
1221 // (2*MEDIAN_HOP_CLTV_EXPIRY_DELTA) here.
1222 let max_total_cltv_expiry_delta = (payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta)
1223 .checked_sub(2*MEDIAN_HOP_CLTV_EXPIRY_DELTA)
1224 .unwrap_or(payment_params.max_total_cltv_expiry_delta - final_cltv_expiry_delta);
1225 let hop_total_cltv_delta = ($next_hops_cltv_delta as u32)
1226 .saturating_add($candidate.cltv_expiry_delta());
1227 let exceeds_cltv_delta_limit = hop_total_cltv_delta > max_total_cltv_expiry_delta;
1229 let value_contribution_msat = cmp::min(available_value_contribution_msat, $next_hops_value_contribution);
1230 // Includes paying fees for the use of the following channels.
1231 let amount_to_transfer_over_msat: u64 = match value_contribution_msat.checked_add($next_hops_fee_msat) {
1232 Some(result) => result,
1233 // Can't overflow due to how the values were computed right above.
1234 None => unreachable!(),
1236 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1237 let over_path_minimum_msat = amount_to_transfer_over_msat >= $candidate.htlc_minimum_msat() &&
1238 amount_to_transfer_over_msat >= $next_hops_path_htlc_minimum_msat;
1240 #[allow(unused_comparisons)] // $next_hops_path_htlc_minimum_msat is 0 in some calls so rustc complains
1241 let may_overpay_to_meet_path_minimum_msat =
1242 ((amount_to_transfer_over_msat < $candidate.htlc_minimum_msat() &&
1243 recommended_value_msat > $candidate.htlc_minimum_msat()) ||
1244 (amount_to_transfer_over_msat < $next_hops_path_htlc_minimum_msat &&
1245 recommended_value_msat > $next_hops_path_htlc_minimum_msat));
1247 let payment_failed_on_this_channel =
1248 payment_params.previously_failed_channels.contains(&short_channel_id);
1250 // If HTLC minimum is larger than the amount we're going to transfer, we shouldn't
1251 // bother considering this channel. If retrying with recommended_value_msat may
1252 // allow us to hit the HTLC minimum limit, set htlc_minimum_limit so that we go
1253 // around again with a higher amount.
1254 if !contributes_sufficient_value || exceeds_max_path_length ||
1255 exceeds_cltv_delta_limit || payment_failed_on_this_channel {
1256 // Path isn't useful, ignore it and move on.
1257 } else if may_overpay_to_meet_path_minimum_msat {
1258 hit_minimum_limit = true;
1259 } else if over_path_minimum_msat {
1260 // Note that low contribution here (limited by available_liquidity_msat)
1261 // might violate htlc_minimum_msat on the hops which are next along the
1262 // payment path (upstream to the payee). To avoid that, we recompute
1263 // path fees knowing the final path contribution after constructing it.
1264 let path_htlc_minimum_msat = compute_fees($next_hops_path_htlc_minimum_msat, $candidate.fees())
1265 .and_then(|fee_msat| fee_msat.checked_add($next_hops_path_htlc_minimum_msat))
1266 .map(|fee_msat| cmp::max(fee_msat, $candidate.htlc_minimum_msat()))
1267 .unwrap_or_else(|| u64::max_value());
1268 let hm_entry = dist.entry($src_node_id);
1269 let old_entry = hm_entry.or_insert_with(|| {
1270 // If there was previously no known way to access the source node
1271 // (recall it goes payee-to-payer) of short_channel_id, first add a
1272 // semi-dummy record just to compute the fees to reach the source node.
1273 // This will affect our decision on selecting short_channel_id
1274 // as a way to reach the $dest_node_id.
1275 let mut fee_base_msat = 0;
1276 let mut fee_proportional_millionths = 0;
1277 if let Some(Some(fees)) = network_nodes.get(&$src_node_id).map(|node| node.lowest_inbound_channel_fees) {
1278 fee_base_msat = fees.base_msat;
1279 fee_proportional_millionths = fees.proportional_millionths;
1282 node_id: $dest_node_id.clone(),
1283 candidate: $candidate.clone(),
1285 src_lowest_inbound_fees: RoutingFees {
1286 base_msat: fee_base_msat,
1287 proportional_millionths: fee_proportional_millionths,
1289 next_hops_fee_msat: u64::max_value(),
1290 hop_use_fee_msat: u64::max_value(),
1291 total_fee_msat: u64::max_value(),
1292 path_htlc_minimum_msat,
1293 path_penalty_msat: u64::max_value(),
1294 was_processed: false,
1295 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1296 value_contribution_msat,
1300 #[allow(unused_mut)] // We only use the mut in cfg(test)
1301 let mut should_process = !old_entry.was_processed;
1302 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1304 // In test/fuzzing builds, we do extra checks to make sure the skipping
1305 // of already-seen nodes only happens in cases we expect (see below).
1306 if !should_process { should_process = true; }
1310 let mut hop_use_fee_msat = 0;
1311 let mut total_fee_msat = $next_hops_fee_msat;
1313 // Ignore hop_use_fee_msat for channel-from-us as we assume all channels-from-us
1314 // will have the same effective-fee
1315 if $src_node_id != our_node_id {
1316 match compute_fees(amount_to_transfer_over_msat, $candidate.fees()) {
1317 // max_value means we'll always fail
1318 // the old_entry.total_fee_msat > total_fee_msat check
1319 None => total_fee_msat = u64::max_value(),
1321 hop_use_fee_msat = fee_msat;
1322 total_fee_msat += hop_use_fee_msat;
1323 // When calculating the lowest inbound fees to a node, we
1324 // calculate fees here not based on the actual value we think
1325 // will flow over this channel, but on the minimum value that
1326 // we'll accept flowing over it. The minimum accepted value
1327 // is a constant through each path collection run, ensuring
1328 // consistent basis. Otherwise we may later find a
1329 // different path to the source node that is more expensive,
1330 // but which we consider to be cheaper because we are capacity
1331 // constrained and the relative fee becomes lower.
1332 match compute_fees(minimal_value_contribution_msat, old_entry.src_lowest_inbound_fees)
1333 .map(|a| a.checked_add(total_fee_msat)) {
1338 total_fee_msat = u64::max_value();
1345 let channel_usage = ChannelUsage {
1346 amount_msat: amount_to_transfer_over_msat,
1347 inflight_htlc_msat: used_liquidity_msat,
1350 let channel_penalty_msat = scorer.channel_penalty_msat(
1351 short_channel_id, &$src_node_id, &$dest_node_id, channel_usage
1353 let path_penalty_msat = $next_hops_path_penalty_msat
1354 .saturating_add(channel_penalty_msat);
1355 let new_graph_node = RouteGraphNode {
1356 node_id: $src_node_id,
1357 lowest_fee_to_peer_through_node: total_fee_msat,
1358 lowest_fee_to_node: $next_hops_fee_msat as u64 + hop_use_fee_msat,
1359 total_cltv_delta: hop_total_cltv_delta,
1360 value_contribution_msat,
1361 path_htlc_minimum_msat,
1363 path_length_to_node,
1366 // Update the way of reaching $src_node_id with the given short_channel_id (from $dest_node_id),
1367 // if this way is cheaper than the already known
1368 // (considering the cost to "reach" this channel from the route destination,
1369 // the cost of using this channel,
1370 // and the cost of routing to the source node of this channel).
1371 // Also, consider that htlc_minimum_msat_difference, because we might end up
1372 // paying it. Consider the following exploit:
1373 // we use 2 paths to transfer 1.5 BTC. One of them is 0-fee normal 1 BTC path,
1374 // and for the other one we picked a 1sat-fee path with htlc_minimum_msat of
1375 // 1 BTC. Now, since the latter is more expensive, we gonna try to cut it
1376 // by 0.5 BTC, but then match htlc_minimum_msat by paying a fee of 0.5 BTC
1378 // Ideally the scoring could be smarter (e.g. 0.5*htlc_minimum_msat here),
1379 // but it may require additional tracking - we don't want to double-count
1380 // the fees included in $next_hops_path_htlc_minimum_msat, but also
1381 // can't use something that may decrease on future hops.
1382 let old_cost = cmp::max(old_entry.total_fee_msat, old_entry.path_htlc_minimum_msat)
1383 .saturating_add(old_entry.path_penalty_msat);
1384 let new_cost = cmp::max(total_fee_msat, path_htlc_minimum_msat)
1385 .saturating_add(path_penalty_msat);
1387 if !old_entry.was_processed && new_cost < old_cost {
1388 targets.push(new_graph_node);
1389 old_entry.next_hops_fee_msat = $next_hops_fee_msat;
1390 old_entry.hop_use_fee_msat = hop_use_fee_msat;
1391 old_entry.total_fee_msat = total_fee_msat;
1392 old_entry.node_id = $dest_node_id.clone();
1393 old_entry.candidate = $candidate.clone();
1394 old_entry.fee_msat = 0; // This value will be later filled with hop_use_fee_msat of the following channel
1395 old_entry.path_htlc_minimum_msat = path_htlc_minimum_msat;
1396 old_entry.path_penalty_msat = path_penalty_msat;
1397 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1399 old_entry.value_contribution_msat = value_contribution_msat;
1401 did_add_update_path_to_src_node = true;
1402 } else if old_entry.was_processed && new_cost < old_cost {
1403 #[cfg(all(not(feature = "_bench_unstable"), any(test, fuzzing)))]
1405 // If we're skipping processing a node which was previously
1406 // processed even though we found another path to it with a
1407 // cheaper fee, check that it was because the second path we
1408 // found (which we are processing now) has a lower value
1409 // contribution due to an HTLC minimum limit.
1411 // e.g. take a graph with two paths from node 1 to node 2, one
1412 // through channel A, and one through channel B. Channel A and
1413 // B are both in the to-process heap, with their scores set by
1414 // a higher htlc_minimum than fee.
1415 // Channel A is processed first, and the channels onwards from
1416 // node 1 are added to the to-process heap. Thereafter, we pop
1417 // Channel B off of the heap, note that it has a much more
1418 // restrictive htlc_maximum_msat, and recalculate the fees for
1419 // all of node 1's channels using the new, reduced, amount.
1421 // This would be bogus - we'd be selecting a higher-fee path
1422 // with a lower htlc_maximum_msat instead of the one we'd
1423 // already decided to use.
1424 debug_assert!(path_htlc_minimum_msat < old_entry.path_htlc_minimum_msat);
1426 value_contribution_msat + path_penalty_msat <
1427 old_entry.value_contribution_msat + old_entry.path_penalty_msat
1435 did_add_update_path_to_src_node
1439 let default_node_features = default_node_features();
1441 // Find ways (channels with destination) to reach a given node and store them
1442 // in the corresponding data structures (routing graph etc).
1443 // $fee_to_target_msat represents how much it costs to reach to this node from the payee,
1444 // meaning how much will be paid in fees after this node (to the best of our knowledge).
1445 // This data can later be helpful to optimize routing (pay lower fees).
1446 macro_rules! add_entries_to_cheapest_to_target_node {
1447 ( $node: expr, $node_id: expr, $fee_to_target_msat: expr, $next_hops_value_contribution: expr,
1448 $next_hops_path_htlc_minimum_msat: expr, $next_hops_path_penalty_msat: expr,
1449 $next_hops_cltv_delta: expr, $next_hops_path_length: expr ) => {
1450 let skip_node = if let Some(elem) = dist.get_mut(&$node_id) {
1451 let was_processed = elem.was_processed;
1452 elem.was_processed = true;
1455 // Entries are added to dist in add_entry!() when there is a channel from a node.
1456 // Because there are no channels from payee, it will not have a dist entry at this point.
1457 // If we're processing any other node, it is always be the result of a channel from it.
1458 assert_eq!($node_id, payee_node_id);
1463 if let Some(first_channels) = first_hop_targets.get(&$node_id) {
1464 for details in first_channels {
1465 let candidate = CandidateRouteHop::FirstHop { details };
1466 add_entry!(candidate, our_node_id, $node_id, $fee_to_target_msat,
1467 $next_hops_value_contribution,
1468 $next_hops_path_htlc_minimum_msat, $next_hops_path_penalty_msat,
1469 $next_hops_cltv_delta, $next_hops_path_length);
1473 let features = if let Some(node_info) = $node.announcement_info.as_ref() {
1476 &default_node_features
1479 if !features.requires_unknown_bits() {
1480 for chan_id in $node.channels.iter() {
1481 let chan = network_channels.get(chan_id).unwrap();
1482 if !chan.features.requires_unknown_bits() {
1483 if let Some((directed_channel, source)) = chan.as_directed_to(&$node_id) {
1484 if first_hops.is_none() || *source != our_node_id {
1485 if directed_channel.direction().enabled {
1486 let candidate = CandidateRouteHop::PublicHop {
1487 info: directed_channel,
1488 short_channel_id: *chan_id,
1490 add_entry!(candidate, *source, $node_id,
1491 $fee_to_target_msat,
1492 $next_hops_value_contribution,
1493 $next_hops_path_htlc_minimum_msat,
1494 $next_hops_path_penalty_msat,
1495 $next_hops_cltv_delta, $next_hops_path_length);
1506 let mut payment_paths = Vec::<PaymentPath>::new();
1508 // TODO: diversify by nodes (so that all paths aren't doomed if one node is offline).
1509 'paths_collection: loop {
1510 // For every new path, start from scratch, except for used_channel_liquidities, which
1511 // helps to avoid reusing previously selected paths in future iterations.
1514 hit_minimum_limit = false;
1516 // If first hop is a private channel and the only way to reach the payee, this is the only
1517 // place where it could be added.
1518 if let Some(first_channels) = first_hop_targets.get(&payee_node_id) {
1519 for details in first_channels {
1520 let candidate = CandidateRouteHop::FirstHop { details };
1521 let added = add_entry!(candidate, our_node_id, payee_node_id, 0, path_value_msat,
1523 log_trace!(logger, "{} direct route to payee via SCID {}",
1524 if added { "Added" } else { "Skipped" }, candidate.short_channel_id());
1528 // Add the payee as a target, so that the payee-to-payer
1529 // search algorithm knows what to start with.
1530 match network_nodes.get(&payee_node_id) {
1531 // The payee is not in our network graph, so nothing to add here.
1532 // There is still a chance of reaching them via last_hops though,
1533 // so don't yet fail the payment here.
1534 // If not, targets.pop() will not even let us enter the loop in step 2.
1537 add_entries_to_cheapest_to_target_node!(node, payee_node_id, 0, path_value_msat, 0, 0u64, 0, 0);
1542 // If a caller provided us with last hops, add them to routing targets. Since this happens
1543 // earlier than general path finding, they will be somewhat prioritized, although currently
1544 // it matters only if the fees are exactly the same.
1545 for route in payment_params.route_hints.iter().filter(|route| !route.0.is_empty()) {
1546 let first_hop_in_route = &(route.0)[0];
1547 let have_hop_src_in_graph =
1548 // Only add the hops in this route to our candidate set if either
1549 // we have a direct channel to the first hop or the first hop is
1550 // in the regular network graph.
1551 first_hop_targets.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some() ||
1552 network_nodes.get(&NodeId::from_pubkey(&first_hop_in_route.src_node_id)).is_some();
1553 if have_hop_src_in_graph {
1554 // We start building the path from reverse, i.e., from payee
1555 // to the first RouteHintHop in the path.
1556 let hop_iter = route.0.iter().rev();
1557 let prev_hop_iter = core::iter::once(&payment_params.payee_pubkey).chain(
1558 route.0.iter().skip(1).rev().map(|hop| &hop.src_node_id));
1559 let mut hop_used = true;
1560 let mut aggregate_next_hops_fee_msat: u64 = 0;
1561 let mut aggregate_next_hops_path_htlc_minimum_msat: u64 = 0;
1562 let mut aggregate_next_hops_path_penalty_msat: u64 = 0;
1563 let mut aggregate_next_hops_cltv_delta: u32 = 0;
1564 let mut aggregate_next_hops_path_length: u8 = 0;
1566 for (idx, (hop, prev_hop_id)) in hop_iter.zip(prev_hop_iter).enumerate() {
1567 let source = NodeId::from_pubkey(&hop.src_node_id);
1568 let target = NodeId::from_pubkey(&prev_hop_id);
1569 let candidate = network_channels
1570 .get(&hop.short_channel_id)
1571 .and_then(|channel| channel.as_directed_to(&target))
1572 .map(|(info, _)| CandidateRouteHop::PublicHop {
1574 short_channel_id: hop.short_channel_id,
1576 .unwrap_or_else(|| CandidateRouteHop::PrivateHop { hint: hop });
1578 if !add_entry!(candidate, source, target, aggregate_next_hops_fee_msat,
1579 path_value_msat, aggregate_next_hops_path_htlc_minimum_msat,
1580 aggregate_next_hops_path_penalty_msat,
1581 aggregate_next_hops_cltv_delta, aggregate_next_hops_path_length) {
1582 // If this hop was not used then there is no use checking the preceding
1583 // hops in the RouteHint. We can break by just searching for a direct
1584 // channel between last checked hop and first_hop_targets.
1588 let used_liquidity_msat = used_channel_liquidities
1589 .get(&(hop.short_channel_id, source < target)).copied().unwrap_or(0);
1590 let channel_usage = ChannelUsage {
1591 amount_msat: final_value_msat + aggregate_next_hops_fee_msat,
1592 inflight_htlc_msat: used_liquidity_msat,
1593 effective_capacity: candidate.effective_capacity(),
1595 let channel_penalty_msat = scorer.channel_penalty_msat(
1596 hop.short_channel_id, &source, &target, channel_usage
1598 aggregate_next_hops_path_penalty_msat = aggregate_next_hops_path_penalty_msat
1599 .saturating_add(channel_penalty_msat);
1601 aggregate_next_hops_cltv_delta = aggregate_next_hops_cltv_delta
1602 .saturating_add(hop.cltv_expiry_delta as u32);
1604 aggregate_next_hops_path_length = aggregate_next_hops_path_length
1607 // Searching for a direct channel between last checked hop and first_hop_targets
1608 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&prev_hop_id)) {
1609 for details in first_channels {
1610 let candidate = CandidateRouteHop::FirstHop { details };
1611 add_entry!(candidate, our_node_id, NodeId::from_pubkey(&prev_hop_id),
1612 aggregate_next_hops_fee_msat, path_value_msat,
1613 aggregate_next_hops_path_htlc_minimum_msat,
1614 aggregate_next_hops_path_penalty_msat, aggregate_next_hops_cltv_delta,
1615 aggregate_next_hops_path_length);
1623 // In the next values of the iterator, the aggregate fees already reflects
1624 // the sum of value sent from payer (final_value_msat) and routing fees
1625 // for the last node in the RouteHint. We need to just add the fees to
1626 // route through the current node so that the preceding node (next iteration)
1628 let hops_fee = compute_fees(aggregate_next_hops_fee_msat + final_value_msat, hop.fees)
1629 .map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
1630 aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
1632 let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
1633 let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
1634 let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
1635 .checked_add(hop_htlc_minimum_msat_inc);
1636 aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
1638 if idx == route.0.len() - 1 {
1639 // The last hop in this iterator is the first hop in
1640 // overall RouteHint.
1641 // If this hop connects to a node with which we have a direct channel,
1642 // ignore the network graph and, if the last hop was added, add our
1643 // direct channel to the candidate set.
1645 // Note that we *must* check if the last hop was added as `add_entry`
1646 // always assumes that the third argument is a node to which we have a
1648 if let Some(first_channels) = first_hop_targets.get(&NodeId::from_pubkey(&hop.src_node_id)) {
1649 for details in first_channels {
1650 let candidate = CandidateRouteHop::FirstHop { details };
1651 add_entry!(candidate, our_node_id,
1652 NodeId::from_pubkey(&hop.src_node_id),
1653 aggregate_next_hops_fee_msat, path_value_msat,
1654 aggregate_next_hops_path_htlc_minimum_msat,
1655 aggregate_next_hops_path_penalty_msat,
1656 aggregate_next_hops_cltv_delta,
1657 aggregate_next_hops_path_length);
1665 log_trace!(logger, "Starting main path collection loop with {} nodes pre-filled from first/last hops.", targets.len());
1667 // At this point, targets are filled with the data from first and
1668 // last hops communicated by the caller, and the payment receiver.
1669 let mut found_new_path = false;
1672 // If this loop terminates due the exhaustion of targets, two situations are possible:
1673 // - not enough outgoing liquidity:
1674 // 0 < already_collected_value_msat < final_value_msat
1675 // - enough outgoing liquidity:
1676 // final_value_msat <= already_collected_value_msat < recommended_value_msat
1677 // Both these cases (and other cases except reaching recommended_value_msat) mean that
1678 // paths_collection will be stopped because found_new_path==false.
1679 // This is not necessarily a routing failure.
1680 'path_construction: while let Some(RouteGraphNode { node_id, lowest_fee_to_node, total_cltv_delta, mut value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat, path_length_to_node, .. }) = targets.pop() {
1682 // Since we're going payee-to-payer, hitting our node as a target means we should stop
1683 // traversing the graph and arrange the path out of what we found.
1684 if node_id == our_node_id {
1685 let mut new_entry = dist.remove(&our_node_id).unwrap();
1686 let mut ordered_hops: Vec<(PathBuildingHop, NodeFeatures)> = vec!((new_entry.clone(), default_node_features.clone()));
1689 let mut features_set = false;
1690 if let Some(first_channels) = first_hop_targets.get(&ordered_hops.last().unwrap().0.node_id) {
1691 for details in first_channels {
1692 if details.get_outbound_payment_scid().unwrap() == ordered_hops.last().unwrap().0.candidate.short_channel_id() {
1693 ordered_hops.last_mut().unwrap().1 = details.counterparty.features.to_context();
1694 features_set = true;
1700 if let Some(node) = network_nodes.get(&ordered_hops.last().unwrap().0.node_id) {
1701 if let Some(node_info) = node.announcement_info.as_ref() {
1702 ordered_hops.last_mut().unwrap().1 = node_info.features.clone();
1704 ordered_hops.last_mut().unwrap().1 = default_node_features.clone();
1707 // We can fill in features for everything except hops which were
1708 // provided via the invoice we're paying. We could guess based on the
1709 // recipient's features but for now we simply avoid guessing at all.
1713 // Means we succesfully traversed from the payer to the payee, now
1714 // save this path for the payment route. Also, update the liquidity
1715 // remaining on the used hops, so that we take them into account
1716 // while looking for more paths.
1717 if ordered_hops.last().unwrap().0.node_id == payee_node_id {
1721 new_entry = match dist.remove(&ordered_hops.last().unwrap().0.node_id) {
1722 Some(payment_hop) => payment_hop,
1723 // We can't arrive at None because, if we ever add an entry to targets,
1724 // we also fill in the entry in dist (see add_entry!).
1725 None => unreachable!(),
1727 // We "propagate" the fees one hop backward (topologically) here,
1728 // so that fees paid for a HTLC forwarding on the current channel are
1729 // associated with the previous channel (where they will be subtracted).
1730 ordered_hops.last_mut().unwrap().0.fee_msat = new_entry.hop_use_fee_msat;
1731 ordered_hops.push((new_entry.clone(), default_node_features.clone()));
1733 ordered_hops.last_mut().unwrap().0.fee_msat = value_contribution_msat;
1734 ordered_hops.last_mut().unwrap().0.hop_use_fee_msat = 0;
1736 log_trace!(logger, "Found a path back to us from the target with {} hops contributing up to {} msat: \n {:#?}",
1737 ordered_hops.len(), value_contribution_msat, ordered_hops.iter().map(|h| &(h.0)).collect::<Vec<&PathBuildingHop>>());
1739 let mut payment_path = PaymentPath {hops: ordered_hops};
1741 // We could have possibly constructed a slightly inconsistent path: since we reduce
1742 // value being transferred along the way, we could have violated htlc_minimum_msat
1743 // on some channels we already passed (assuming dest->source direction). Here, we
1744 // recompute the fees again, so that if that's the case, we match the currently
1745 // underpaid htlc_minimum_msat with fees.
1746 debug_assert_eq!(payment_path.get_value_msat(), value_contribution_msat);
1747 value_contribution_msat = cmp::min(value_contribution_msat, final_value_msat);
1748 payment_path.update_value_and_recompute_fees(value_contribution_msat);
1750 // Since a path allows to transfer as much value as
1751 // the smallest channel it has ("bottleneck"), we should recompute
1752 // the fees so sender HTLC don't overpay fees when traversing
1753 // larger channels than the bottleneck. This may happen because
1754 // when we were selecting those channels we were not aware how much value
1755 // this path will transfer, and the relative fee for them
1756 // might have been computed considering a larger value.
1757 // Remember that we used these channels so that we don't rely
1758 // on the same liquidity in future paths.
1759 let mut prevented_redundant_path_selection = false;
1760 let prev_hop_iter = core::iter::once(&our_node_id)
1761 .chain(payment_path.hops.iter().map(|(hop, _)| &hop.node_id));
1762 for (prev_hop, (hop, _)) in prev_hop_iter.zip(payment_path.hops.iter()) {
1763 let spent_on_hop_msat = value_contribution_msat + hop.next_hops_fee_msat;
1764 let used_liquidity_msat = used_channel_liquidities
1765 .entry((hop.candidate.short_channel_id(), *prev_hop < hop.node_id))
1766 .and_modify(|used_liquidity_msat| *used_liquidity_msat += spent_on_hop_msat)
1767 .or_insert(spent_on_hop_msat);
1768 let hop_capacity = hop.candidate.effective_capacity();
1769 let hop_max_msat = max_htlc_from_capacity(hop_capacity, channel_saturation_pow_half);
1770 if *used_liquidity_msat == hop_max_msat {
1771 // If this path used all of this channel's available liquidity, we know
1772 // this path will not be selected again in the next loop iteration.
1773 prevented_redundant_path_selection = true;
1775 debug_assert!(*used_liquidity_msat <= hop_max_msat);
1777 if !prevented_redundant_path_selection {
1778 // If we weren't capped by hitting a liquidity limit on a channel in the path,
1779 // we'll probably end up picking the same path again on the next iteration.
1780 // Decrease the available liquidity of a hop in the middle of the path.
1781 let victim_scid = payment_path.hops[(payment_path.hops.len()) / 2].0.candidate.short_channel_id();
1782 let exhausted = u64::max_value();
1783 log_trace!(logger, "Disabling channel {} for future path building iterations to avoid duplicates.", victim_scid);
1784 *used_channel_liquidities.entry((victim_scid, false)).or_default() = exhausted;
1785 *used_channel_liquidities.entry((victim_scid, true)).or_default() = exhausted;
1788 // Track the total amount all our collected paths allow to send so that we know
1789 // when to stop looking for more paths
1790 already_collected_value_msat += value_contribution_msat;
1792 payment_paths.push(payment_path);
1793 found_new_path = true;
1794 break 'path_construction;
1797 // If we found a path back to the payee, we shouldn't try to process it again. This is
1798 // the equivalent of the `elem.was_processed` check in
1799 // add_entries_to_cheapest_to_target_node!() (see comment there for more info).
1800 if node_id == payee_node_id { continue 'path_construction; }
1802 // Otherwise, since the current target node is not us,
1803 // keep "unrolling" the payment graph from payee to payer by
1804 // finding a way to reach the current target from the payer side.
1805 match network_nodes.get(&node_id) {
1808 add_entries_to_cheapest_to_target_node!(node, node_id, lowest_fee_to_node,
1809 value_contribution_msat, path_htlc_minimum_msat, path_penalty_msat,
1810 total_cltv_delta, path_length_to_node);
1816 if !found_new_path && channel_saturation_pow_half != 0 {
1817 channel_saturation_pow_half = 0;
1818 continue 'paths_collection;
1820 // If we don't support MPP, no use trying to gather more value ever.
1821 break 'paths_collection;
1825 // Stop either when the recommended value is reached or if no new path was found in this
1827 // In the latter case, making another path finding attempt won't help,
1828 // because we deterministically terminated the search due to low liquidity.
1829 if !found_new_path && channel_saturation_pow_half != 0 {
1830 channel_saturation_pow_half = 0;
1831 } else if already_collected_value_msat >= recommended_value_msat || !found_new_path {
1832 log_trace!(logger, "Have now collected {} msat (seeking {} msat) in paths. Last path loop {} a new path.",
1833 already_collected_value_msat, recommended_value_msat, if found_new_path { "found" } else { "did not find" });
1834 break 'paths_collection;
1835 } else if found_new_path && already_collected_value_msat == final_value_msat && payment_paths.len() == 1 {
1836 // Further, if this was our first walk of the graph, and we weren't limited by an
1837 // htlc_minimum_msat, return immediately because this path should suffice. If we were
1838 // limited by an htlc_minimum_msat value, find another path with a higher value,
1839 // potentially allowing us to pay fees to meet the htlc_minimum on the new path while
1840 // still keeping a lower total fee than this path.
1841 if !hit_minimum_limit {
1842 log_trace!(logger, "Collected exactly our payment amount on the first pass, without hitting an htlc_minimum_msat limit, exiting.");
1843 break 'paths_collection;
1845 log_trace!(logger, "Collected our payment amount on the first pass, but running again to collect extra paths with a potentially higher limit.");
1846 path_value_msat = recommended_value_msat;
1851 if payment_paths.len() == 0 {
1852 return Err(LightningError{err: "Failed to find a path to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1855 if already_collected_value_msat < final_value_msat {
1856 return Err(LightningError{err: "Failed to find a sufficient route to the given destination".to_owned(), action: ErrorAction::IgnoreError});
1860 let mut selected_route = payment_paths;
1862 debug_assert_eq!(selected_route.iter().map(|p| p.get_value_msat()).sum::<u64>(), already_collected_value_msat);
1863 let mut overpaid_value_msat = already_collected_value_msat - final_value_msat;
1865 // First, sort by the cost-per-value of the path, dropping the paths that cost the most for
1866 // the value they contribute towards the payment amount.
1867 // We sort in descending order as we will remove from the front in `retain`, next.
1868 selected_route.sort_unstable_by(|a, b|
1869 (((b.get_cost_msat() as u128) << 64) / (b.get_value_msat() as u128))
1870 .cmp(&(((a.get_cost_msat() as u128) << 64) / (a.get_value_msat() as u128)))
1873 // We should make sure that at least 1 path left.
1874 let mut paths_left = selected_route.len();
1875 selected_route.retain(|path| {
1876 if paths_left == 1 {
1879 let path_value_msat = path.get_value_msat();
1880 if path_value_msat <= overpaid_value_msat {
1881 overpaid_value_msat -= path_value_msat;
1887 debug_assert!(selected_route.len() > 0);
1889 if overpaid_value_msat != 0 {
1891 // Now, subtract the remaining overpaid value from the most-expensive path.
1892 // TODO: this could also be optimized by also sorting by feerate_per_sat_routed,
1893 // so that the sender pays less fees overall. And also htlc_minimum_msat.
1894 selected_route.sort_unstable_by(|a, b| {
1895 let a_f = a.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1896 let b_f = b.hops.iter().map(|hop| hop.0.candidate.fees().proportional_millionths as u64).sum::<u64>();
1897 a_f.cmp(&b_f).then_with(|| b.get_cost_msat().cmp(&a.get_cost_msat()))
1899 let expensive_payment_path = selected_route.first_mut().unwrap();
1901 // We already dropped all the paths with value below `overpaid_value_msat` above, thus this
1902 // can't go negative.
1903 let expensive_path_new_value_msat = expensive_payment_path.get_value_msat() - overpaid_value_msat;
1904 expensive_payment_path.update_value_and_recompute_fees(expensive_path_new_value_msat);
1908 // Sort by the path itself and combine redundant paths.
1909 // Note that we sort by SCIDs alone as its simpler but when combining we have to ensure we
1910 // compare both SCIDs and NodeIds as individual nodes may use random aliases causing collisions
1912 selected_route.sort_unstable_by_key(|path| {
1913 let mut key = [0u64; MAX_PATH_LENGTH_ESTIMATE as usize];
1914 debug_assert!(path.hops.len() <= key.len());
1915 for (scid, key) in path.hops.iter().map(|h| h.0.candidate.short_channel_id()).zip(key.iter_mut()) {
1920 for idx in 0..(selected_route.len() - 1) {
1921 if idx + 1 >= selected_route.len() { break; }
1922 if iter_equal(selected_route[idx ].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id)),
1923 selected_route[idx + 1].hops.iter().map(|h| (h.0.candidate.short_channel_id(), h.0.node_id))) {
1924 let new_value = selected_route[idx].get_value_msat() + selected_route[idx + 1].get_value_msat();
1925 selected_route[idx].update_value_and_recompute_fees(new_value);
1926 selected_route.remove(idx + 1);
1930 let mut selected_paths = Vec::<Vec<Result<RouteHop, LightningError>>>::new();
1931 for payment_path in selected_route {
1932 let mut path = payment_path.hops.iter().map(|(payment_hop, node_features)| {
1934 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)})?,
1935 node_features: node_features.clone(),
1936 short_channel_id: payment_hop.candidate.short_channel_id(),
1937 channel_features: payment_hop.candidate.features(),
1938 fee_msat: payment_hop.fee_msat,
1939 cltv_expiry_delta: payment_hop.candidate.cltv_expiry_delta(),
1941 }).collect::<Vec<_>>();
1942 // Propagate the cltv_expiry_delta one hop backwards since the delta from the current hop is
1943 // applicable for the previous hop.
1944 path.iter_mut().rev().fold(final_cltv_expiry_delta, |prev_cltv_expiry_delta, hop| {
1945 core::mem::replace(&mut hop.as_mut().unwrap().cltv_expiry_delta, prev_cltv_expiry_delta)
1947 selected_paths.push(path);
1949 // Make sure we would never create a route with more paths than we allow.
1950 debug_assert!(selected_paths.len() <= payment_params.max_path_count.into());
1952 if let Some(features) = &payment_params.features {
1953 for path in selected_paths.iter_mut() {
1954 if let Ok(route_hop) = path.last_mut().unwrap() {
1955 route_hop.node_features = features.to_context();
1961 paths: selected_paths.into_iter().map(|path| path.into_iter().collect()).collect::<Result<Vec<_>, _>>()?,
1962 payment_params: Some(payment_params.clone()),
1964 log_info!(logger, "Got route to {}: {}", payment_params.payee_pubkey, log_route!(route));
1968 // When an adversarial intermediary node observes a payment, it may be able to infer its
1969 // destination, if the remaining CLTV expiry delta exactly matches a feasible path in the network
1970 // graph. In order to improve privacy, this method obfuscates the CLTV expiry deltas along the
1971 // payment path by adding a randomized 'shadow route' offset to the final hop.
1972 fn add_random_cltv_offset(route: &mut Route, payment_params: &PaymentParameters,
1973 network_graph: &ReadOnlyNetworkGraph, random_seed_bytes: &[u8; 32]
1975 let network_channels = network_graph.channels();
1976 let network_nodes = network_graph.nodes();
1978 for path in route.paths.iter_mut() {
1979 let mut shadow_ctlv_expiry_delta_offset: u32 = 0;
1981 // Remember the last three nodes of the random walk and avoid looping back on them.
1982 // Init with the last three nodes from the actual path, if possible.
1983 let mut nodes_to_avoid: [NodeId; 3] = [NodeId::from_pubkey(&path.last().unwrap().pubkey),
1984 NodeId::from_pubkey(&path.get(path.len().saturating_sub(2)).unwrap().pubkey),
1985 NodeId::from_pubkey(&path.get(path.len().saturating_sub(3)).unwrap().pubkey)];
1987 // Choose the last publicly known node as the starting point for the random walk.
1988 let mut cur_hop: Option<NodeId> = None;
1989 let mut path_nonce = [0u8; 12];
1990 if let Some(starting_hop) = path.iter().rev()
1991 .find(|h| network_nodes.contains_key(&NodeId::from_pubkey(&h.pubkey))) {
1992 cur_hop = Some(NodeId::from_pubkey(&starting_hop.pubkey));
1993 path_nonce.copy_from_slice(&cur_hop.unwrap().as_slice()[..12]);
1996 // Init PRNG with the path-dependant nonce, which is static for private paths.
1997 let mut prng = ChaCha20::new(random_seed_bytes, &path_nonce);
1998 let mut random_path_bytes = [0u8; ::core::mem::size_of::<usize>()];
2000 // Pick a random path length in [1 .. 3]
2001 prng.process_in_place(&mut random_path_bytes);
2002 let random_walk_length = usize::from_be_bytes(random_path_bytes).wrapping_rem(3).wrapping_add(1);
2004 for random_hop in 0..random_walk_length {
2005 // If we don't find a suitable offset in the public network graph, we default to
2006 // MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2007 let mut random_hop_offset = MEDIAN_HOP_CLTV_EXPIRY_DELTA;
2009 if let Some(cur_node_id) = cur_hop {
2010 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
2011 // Randomly choose the next unvisited hop.
2012 prng.process_in_place(&mut random_path_bytes);
2013 if let Some(random_channel) = usize::from_be_bytes(random_path_bytes)
2014 .checked_rem(cur_node.channels.len())
2015 .and_then(|index| cur_node.channels.get(index))
2016 .and_then(|id| network_channels.get(id)) {
2017 random_channel.as_directed_from(&cur_node_id).map(|(dir_info, next_id)| {
2018 if !nodes_to_avoid.iter().any(|x| x == next_id) {
2019 nodes_to_avoid[random_hop] = *next_id;
2020 random_hop_offset = dir_info.direction().cltv_expiry_delta.into();
2021 cur_hop = Some(*next_id);
2028 shadow_ctlv_expiry_delta_offset = shadow_ctlv_expiry_delta_offset
2029 .checked_add(random_hop_offset)
2030 .unwrap_or(shadow_ctlv_expiry_delta_offset);
2033 // Limit the total offset to reduce the worst-case locked liquidity timevalue
2034 const MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET: u32 = 3*144;
2035 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, MAX_SHADOW_CLTV_EXPIRY_DELTA_OFFSET);
2037 // Limit the offset so we never exceed the max_total_cltv_expiry_delta. To improve plausibility,
2038 // we choose the limit to be the largest possible multiple of MEDIAN_HOP_CLTV_EXPIRY_DELTA.
2039 let path_total_cltv_expiry_delta: u32 = path.iter().map(|h| h.cltv_expiry_delta).sum();
2040 let mut max_path_offset = payment_params.max_total_cltv_expiry_delta - path_total_cltv_expiry_delta;
2041 max_path_offset = cmp::max(
2042 max_path_offset - (max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA),
2043 max_path_offset % MEDIAN_HOP_CLTV_EXPIRY_DELTA);
2044 shadow_ctlv_expiry_delta_offset = cmp::min(shadow_ctlv_expiry_delta_offset, max_path_offset);
2046 // Add 'shadow' CLTV offset to the final hop
2047 if let Some(last_hop) = path.last_mut() {
2048 last_hop.cltv_expiry_delta = last_hop.cltv_expiry_delta
2049 .checked_add(shadow_ctlv_expiry_delta_offset).unwrap_or(last_hop.cltv_expiry_delta);
2054 /// Construct a route from us (payer) to the target node (payee) via the given hops (which should
2055 /// exclude the payer, but include the payee). This may be useful, e.g., for probing the chosen path.
2057 /// Re-uses logic from `find_route`, so the restrictions described there also apply here.
2058 pub fn build_route_from_hops<L: Deref, GL: Deref>(
2059 our_node_pubkey: &PublicKey, hops: &[PublicKey], route_params: &RouteParameters,
2060 network_graph: &NetworkGraph<GL>, logger: L, random_seed_bytes: &[u8; 32]
2061 ) -> Result<Route, LightningError>
2062 where L::Target: Logger, GL::Target: Logger {
2063 let graph_lock = network_graph.read_only();
2064 let mut route = build_route_from_hops_internal(
2065 our_node_pubkey, hops, &route_params.payment_params, &graph_lock,
2066 route_params.final_value_msat, route_params.final_cltv_expiry_delta, logger, random_seed_bytes)?;
2067 add_random_cltv_offset(&mut route, &route_params.payment_params, &graph_lock, random_seed_bytes);
2071 fn build_route_from_hops_internal<L: Deref>(
2072 our_node_pubkey: &PublicKey, hops: &[PublicKey], payment_params: &PaymentParameters,
2073 network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
2074 logger: L, random_seed_bytes: &[u8; 32]
2075 ) -> Result<Route, LightningError> where L::Target: Logger {
2078 our_node_id: NodeId,
2079 hop_ids: [Option<NodeId>; MAX_PATH_LENGTH_ESTIMATE as usize],
2082 impl Score for HopScorer {
2083 fn channel_penalty_msat(&self, _short_channel_id: u64, source: &NodeId, target: &NodeId,
2084 _usage: ChannelUsage) -> u64
2086 let mut cur_id = self.our_node_id;
2087 for i in 0..self.hop_ids.len() {
2088 if let Some(next_id) = self.hop_ids[i] {
2089 if cur_id == *source && next_id == *target {
2100 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
2102 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
2104 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
2106 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
2109 impl<'a> Writeable for HopScorer {
2111 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), io::Error> {
2116 if hops.len() > MAX_PATH_LENGTH_ESTIMATE.into() {
2117 return Err(LightningError{err: "Cannot build a route exceeding the maximum path length.".to_owned(), action: ErrorAction::IgnoreError});
2120 let our_node_id = NodeId::from_pubkey(our_node_pubkey);
2121 let mut hop_ids = [None; MAX_PATH_LENGTH_ESTIMATE as usize];
2122 for i in 0..hops.len() {
2123 hop_ids[i] = Some(NodeId::from_pubkey(&hops[i]));
2126 let scorer = HopScorer { our_node_id, hop_ids };
2128 get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
2129 final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)
2134 use crate::routing::gossip::{NetworkGraph, P2PGossipSync, NodeId, EffectiveCapacity};
2135 use crate::routing::router::{get_route, build_route_from_hops_internal, add_random_cltv_offset, default_node_features,
2136 PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RoutingFees,
2137 DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA, MAX_PATH_LENGTH_ESTIMATE};
2138 use crate::routing::scoring::{ChannelUsage, Score, ProbabilisticScorer, ProbabilisticScoringParameters};
2139 use crate::routing::test_utils::{add_channel, add_or_update_node, build_graph, build_line_graph, id_to_feature_flags, get_nodes, update_channel};
2140 use crate::chain::transaction::OutPoint;
2141 use crate::chain::keysinterface::KeysInterface;
2142 use crate::ln::features::{ChannelFeatures, InitFeatures, NodeFeatures};
2143 use crate::ln::msgs::{ErrorAction, LightningError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
2144 use crate::ln::channelmanager;
2145 use crate::util::test_utils as ln_test_utils;
2146 use crate::util::chacha20::ChaCha20;
2148 use crate::util::ser::{Writeable, Writer};
2150 use bitcoin::hashes::Hash;
2151 use bitcoin::network::constants::Network;
2152 use bitcoin::blockdata::constants::genesis_block;
2153 use bitcoin::blockdata::script::Builder;
2154 use bitcoin::blockdata::opcodes;
2155 use bitcoin::blockdata::transaction::TxOut;
2159 use bitcoin::secp256k1::{PublicKey,SecretKey};
2160 use bitcoin::secp256k1::Secp256k1;
2162 use crate::prelude::*;
2163 use crate::sync::Arc;
2165 use core::convert::TryInto;
2167 fn get_channel_details(short_channel_id: Option<u64>, node_id: PublicKey,
2168 features: InitFeatures, outbound_capacity_msat: u64) -> channelmanager::ChannelDetails {
2169 channelmanager::ChannelDetails {
2170 channel_id: [0; 32],
2171 counterparty: channelmanager::ChannelCounterparty {
2174 unspendable_punishment_reserve: 0,
2175 forwarding_info: None,
2176 outbound_htlc_minimum_msat: None,
2177 outbound_htlc_maximum_msat: None,
2179 funding_txo: Some(OutPoint { txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0 }),
2182 outbound_scid_alias: None,
2183 inbound_scid_alias: None,
2184 channel_value_satoshis: 0,
2187 outbound_capacity_msat,
2188 next_outbound_htlc_limit_msat: outbound_capacity_msat,
2189 inbound_capacity_msat: 42,
2190 unspendable_punishment_reserve: None,
2191 confirmations_required: None,
2192 force_close_spend_delay: None,
2193 is_outbound: true, is_channel_ready: true,
2194 is_usable: true, is_public: true,
2195 inbound_htlc_minimum_msat: None,
2196 inbound_htlc_maximum_msat: None,
2202 fn simple_route_test() {
2203 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2204 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2205 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2206 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2207 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2208 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2210 // Simple route to 2 via 1
2212 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) {
2213 assert_eq!(err, "Cannot send a payment of 0 msat");
2214 } else { panic!(); }
2216 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2217 assert_eq!(route.paths[0].len(), 2);
2219 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2220 assert_eq!(route.paths[0][0].short_channel_id, 2);
2221 assert_eq!(route.paths[0][0].fee_msat, 100);
2222 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2223 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2224 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2226 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2227 assert_eq!(route.paths[0][1].short_channel_id, 4);
2228 assert_eq!(route.paths[0][1].fee_msat, 100);
2229 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2230 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2231 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2235 fn invalid_first_hop_test() {
2236 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2237 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2238 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2239 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2240 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2241 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2243 // Simple route to 2 via 1
2245 let our_chans = vec![get_channel_details(Some(2), our_id, InitFeatures::from_le_bytes(vec![0b11]), 100000)];
2247 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) =
2248 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) {
2249 assert_eq!(err, "First hop cannot have our_node_pubkey as a destination.");
2250 } else { panic!(); }
2252 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2253 assert_eq!(route.paths[0].len(), 2);
2257 fn htlc_minimum_test() {
2258 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2259 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2260 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2261 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2262 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2263 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2265 // Simple route to 2 via 1
2267 // Disable other paths
2268 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2269 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2270 short_channel_id: 12,
2272 flags: 2, // to disable
2273 cltv_expiry_delta: 0,
2274 htlc_minimum_msat: 0,
2275 htlc_maximum_msat: MAX_VALUE_MSAT,
2277 fee_proportional_millionths: 0,
2278 excess_data: Vec::new()
2280 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
2281 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2282 short_channel_id: 3,
2284 flags: 2, // to disable
2285 cltv_expiry_delta: 0,
2286 htlc_minimum_msat: 0,
2287 htlc_maximum_msat: MAX_VALUE_MSAT,
2289 fee_proportional_millionths: 0,
2290 excess_data: Vec::new()
2292 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2293 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2294 short_channel_id: 13,
2296 flags: 2, // to disable
2297 cltv_expiry_delta: 0,
2298 htlc_minimum_msat: 0,
2299 htlc_maximum_msat: MAX_VALUE_MSAT,
2301 fee_proportional_millionths: 0,
2302 excess_data: Vec::new()
2304 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2305 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2306 short_channel_id: 6,
2308 flags: 2, // to disable
2309 cltv_expiry_delta: 0,
2310 htlc_minimum_msat: 0,
2311 htlc_maximum_msat: MAX_VALUE_MSAT,
2313 fee_proportional_millionths: 0,
2314 excess_data: Vec::new()
2316 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2317 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2318 short_channel_id: 7,
2320 flags: 2, // to disable
2321 cltv_expiry_delta: 0,
2322 htlc_minimum_msat: 0,
2323 htlc_maximum_msat: MAX_VALUE_MSAT,
2325 fee_proportional_millionths: 0,
2326 excess_data: Vec::new()
2329 // Check against amount_to_transfer_over_msat.
2330 // Set minimal HTLC of 200_000_000 msat.
2331 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2332 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2333 short_channel_id: 2,
2336 cltv_expiry_delta: 0,
2337 htlc_minimum_msat: 200_000_000,
2338 htlc_maximum_msat: MAX_VALUE_MSAT,
2340 fee_proportional_millionths: 0,
2341 excess_data: Vec::new()
2344 // Second hop only allows to forward 199_999_999 at most, thus not allowing the first hop to
2346 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2347 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2348 short_channel_id: 4,
2351 cltv_expiry_delta: 0,
2352 htlc_minimum_msat: 0,
2353 htlc_maximum_msat: 199_999_999,
2355 fee_proportional_millionths: 0,
2356 excess_data: Vec::new()
2359 // Not possible to send 199_999_999, because the minimum on channel=2 is 200_000_000.
2360 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) {
2361 assert_eq!(err, "Failed to find a path to the given destination");
2362 } else { panic!(); }
2364 // Lift the restriction on the first hop.
2365 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2366 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2367 short_channel_id: 2,
2370 cltv_expiry_delta: 0,
2371 htlc_minimum_msat: 0,
2372 htlc_maximum_msat: MAX_VALUE_MSAT,
2374 fee_proportional_millionths: 0,
2375 excess_data: Vec::new()
2378 // A payment above the minimum should pass
2379 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();
2380 assert_eq!(route.paths[0].len(), 2);
2384 fn htlc_minimum_overpay_test() {
2385 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2386 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2387 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
2388 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2389 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2390 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2392 // A route to node#2 via two paths.
2393 // One path allows transferring 35-40 sats, another one also allows 35-40 sats.
2394 // Thus, they can't send 60 without overpaying.
2395 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2396 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2397 short_channel_id: 2,
2400 cltv_expiry_delta: 0,
2401 htlc_minimum_msat: 35_000,
2402 htlc_maximum_msat: 40_000,
2404 fee_proportional_millionths: 0,
2405 excess_data: Vec::new()
2407 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2408 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2409 short_channel_id: 12,
2412 cltv_expiry_delta: 0,
2413 htlc_minimum_msat: 35_000,
2414 htlc_maximum_msat: 40_000,
2416 fee_proportional_millionths: 0,
2417 excess_data: Vec::new()
2421 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
2422 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2423 short_channel_id: 13,
2426 cltv_expiry_delta: 0,
2427 htlc_minimum_msat: 0,
2428 htlc_maximum_msat: MAX_VALUE_MSAT,
2430 fee_proportional_millionths: 0,
2431 excess_data: Vec::new()
2433 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2434 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2435 short_channel_id: 4,
2438 cltv_expiry_delta: 0,
2439 htlc_minimum_msat: 0,
2440 htlc_maximum_msat: MAX_VALUE_MSAT,
2442 fee_proportional_millionths: 0,
2443 excess_data: Vec::new()
2446 // Disable other paths
2447 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2448 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2449 short_channel_id: 1,
2451 flags: 2, // to disable
2452 cltv_expiry_delta: 0,
2453 htlc_minimum_msat: 0,
2454 htlc_maximum_msat: MAX_VALUE_MSAT,
2456 fee_proportional_millionths: 0,
2457 excess_data: Vec::new()
2460 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2461 // Overpay fees to hit htlc_minimum_msat.
2462 let overpaid_fees = route.paths[0][0].fee_msat + route.paths[1][0].fee_msat;
2463 // TODO: this could be better balanced to overpay 10k and not 15k.
2464 assert_eq!(overpaid_fees, 15_000);
2466 // Now, test that if there are 2 paths, a "cheaper" by fee path wouldn't be prioritized
2467 // while taking even more fee to match htlc_minimum_msat.
2468 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2469 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2470 short_channel_id: 12,
2473 cltv_expiry_delta: 0,
2474 htlc_minimum_msat: 65_000,
2475 htlc_maximum_msat: 80_000,
2477 fee_proportional_millionths: 0,
2478 excess_data: Vec::new()
2480 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2481 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2482 short_channel_id: 2,
2485 cltv_expiry_delta: 0,
2486 htlc_minimum_msat: 0,
2487 htlc_maximum_msat: MAX_VALUE_MSAT,
2489 fee_proportional_millionths: 0,
2490 excess_data: Vec::new()
2492 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2493 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2494 short_channel_id: 4,
2497 cltv_expiry_delta: 0,
2498 htlc_minimum_msat: 0,
2499 htlc_maximum_msat: MAX_VALUE_MSAT,
2501 fee_proportional_millionths: 100_000,
2502 excess_data: Vec::new()
2505 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2506 // Fine to overpay for htlc_minimum_msat if it allows us to save fee.
2507 assert_eq!(route.paths.len(), 1);
2508 assert_eq!(route.paths[0][0].short_channel_id, 12);
2509 let fees = route.paths[0][0].fee_msat;
2510 assert_eq!(fees, 5_000);
2512 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2513 // Not fine to overpay for htlc_minimum_msat if it requires paying more than fee on
2514 // the other channel.
2515 assert_eq!(route.paths.len(), 1);
2516 assert_eq!(route.paths[0][0].short_channel_id, 2);
2517 let fees = route.paths[0][0].fee_msat;
2518 assert_eq!(fees, 5_000);
2522 fn disable_channels_test() {
2523 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2524 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2525 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2526 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2527 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2528 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2530 // // Disable channels 4 and 12 by flags=2
2531 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
2532 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2533 short_channel_id: 4,
2535 flags: 2, // to disable
2536 cltv_expiry_delta: 0,
2537 htlc_minimum_msat: 0,
2538 htlc_maximum_msat: MAX_VALUE_MSAT,
2540 fee_proportional_millionths: 0,
2541 excess_data: Vec::new()
2543 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
2544 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2545 short_channel_id: 12,
2547 flags: 2, // to disable
2548 cltv_expiry_delta: 0,
2549 htlc_minimum_msat: 0,
2550 htlc_maximum_msat: MAX_VALUE_MSAT,
2552 fee_proportional_millionths: 0,
2553 excess_data: Vec::new()
2556 // If all the channels require some features we don't understand, route should fail
2557 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
2558 assert_eq!(err, "Failed to find a path to the given destination");
2559 } else { panic!(); }
2561 // If we specify a channel to node7, that overrides our local channel view and that gets used
2562 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2563 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&our_chans.iter().collect::<Vec<_>>()), 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2564 assert_eq!(route.paths[0].len(), 2);
2566 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2567 assert_eq!(route.paths[0][0].short_channel_id, 42);
2568 assert_eq!(route.paths[0][0].fee_msat, 200);
2569 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2570 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2571 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2573 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2574 assert_eq!(route.paths[0][1].short_channel_id, 13);
2575 assert_eq!(route.paths[0][1].fee_msat, 100);
2576 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2577 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2578 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2582 fn disable_node_test() {
2583 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2584 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2585 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2586 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2587 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2588 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2590 // Disable nodes 1, 2, and 8 by requiring unknown feature bits
2591 let mut unknown_features = NodeFeatures::empty();
2592 unknown_features.set_unknown_feature_required();
2593 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[0], unknown_features.clone(), 1);
2594 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], unknown_features.clone(), 1);
2595 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[7], unknown_features.clone(), 1);
2597 // If all nodes require some features we don't understand, route should fail
2598 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) {
2599 assert_eq!(err, "Failed to find a path to the given destination");
2600 } else { panic!(); }
2602 // If we specify a channel to node7, that overrides our local channel view and that gets used
2603 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2604 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();
2605 assert_eq!(route.paths[0].len(), 2);
2607 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2608 assert_eq!(route.paths[0][0].short_channel_id, 42);
2609 assert_eq!(route.paths[0][0].fee_msat, 200);
2610 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2611 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]); // it should also override our view of their features
2612 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2614 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2615 assert_eq!(route.paths[0][1].short_channel_id, 13);
2616 assert_eq!(route.paths[0][1].fee_msat, 100);
2617 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2618 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2619 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2621 // Note that we don't test disabling node 3 and failing to route to it, as we (somewhat
2622 // naively) assume that the user checked the feature bits on the invoice, which override
2623 // the node_announcement.
2627 fn our_chans_test() {
2628 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2629 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2630 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2631 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2632 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2634 // Route to 1 via 2 and 3 because our channel to 1 is disabled
2635 let payment_params = PaymentParameters::from_node_id(nodes[0]);
2636 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2637 assert_eq!(route.paths[0].len(), 3);
2639 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2640 assert_eq!(route.paths[0][0].short_channel_id, 2);
2641 assert_eq!(route.paths[0][0].fee_msat, 200);
2642 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2643 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2644 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2646 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2647 assert_eq!(route.paths[0][1].short_channel_id, 4);
2648 assert_eq!(route.paths[0][1].fee_msat, 100);
2649 assert_eq!(route.paths[0][1].cltv_expiry_delta, (3 << 4) | 2);
2650 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2651 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2653 assert_eq!(route.paths[0][2].pubkey, nodes[0]);
2654 assert_eq!(route.paths[0][2].short_channel_id, 3);
2655 assert_eq!(route.paths[0][2].fee_msat, 100);
2656 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
2657 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(1));
2658 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(3));
2660 // If we specify a channel to node7, that overrides our local channel view and that gets used
2661 let payment_params = PaymentParameters::from_node_id(nodes[2]);
2662 let our_chans = vec![get_channel_details(Some(42), nodes[7].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
2663 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();
2664 assert_eq!(route.paths[0].len(), 2);
2666 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
2667 assert_eq!(route.paths[0][0].short_channel_id, 42);
2668 assert_eq!(route.paths[0][0].fee_msat, 200);
2669 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
2670 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
2671 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
2673 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2674 assert_eq!(route.paths[0][1].short_channel_id, 13);
2675 assert_eq!(route.paths[0][1].fee_msat, 100);
2676 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
2677 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2678 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
2681 fn last_hops(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2682 let zero_fees = RoutingFees {
2684 proportional_millionths: 0,
2686 vec![RouteHint(vec![RouteHintHop {
2687 src_node_id: nodes[3],
2688 short_channel_id: 8,
2690 cltv_expiry_delta: (8 << 4) | 1,
2691 htlc_minimum_msat: None,
2692 htlc_maximum_msat: None,
2694 ]), RouteHint(vec![RouteHintHop {
2695 src_node_id: nodes[4],
2696 short_channel_id: 9,
2699 proportional_millionths: 0,
2701 cltv_expiry_delta: (9 << 4) | 1,
2702 htlc_minimum_msat: None,
2703 htlc_maximum_msat: None,
2704 }]), RouteHint(vec![RouteHintHop {
2705 src_node_id: nodes[5],
2706 short_channel_id: 10,
2708 cltv_expiry_delta: (10 << 4) | 1,
2709 htlc_minimum_msat: None,
2710 htlc_maximum_msat: None,
2714 fn last_hops_multi_private_channels(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2715 let zero_fees = RoutingFees {
2717 proportional_millionths: 0,
2719 vec![RouteHint(vec![RouteHintHop {
2720 src_node_id: nodes[2],
2721 short_channel_id: 5,
2724 proportional_millionths: 0,
2726 cltv_expiry_delta: (5 << 4) | 1,
2727 htlc_minimum_msat: None,
2728 htlc_maximum_msat: None,
2730 src_node_id: nodes[3],
2731 short_channel_id: 8,
2733 cltv_expiry_delta: (8 << 4) | 1,
2734 htlc_minimum_msat: None,
2735 htlc_maximum_msat: None,
2737 ]), RouteHint(vec![RouteHintHop {
2738 src_node_id: nodes[4],
2739 short_channel_id: 9,
2742 proportional_millionths: 0,
2744 cltv_expiry_delta: (9 << 4) | 1,
2745 htlc_minimum_msat: None,
2746 htlc_maximum_msat: None,
2747 }]), RouteHint(vec![RouteHintHop {
2748 src_node_id: nodes[5],
2749 short_channel_id: 10,
2751 cltv_expiry_delta: (10 << 4) | 1,
2752 htlc_minimum_msat: None,
2753 htlc_maximum_msat: None,
2758 fn partial_route_hint_test() {
2759 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2760 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2761 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2762 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2763 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2765 // Simple test across 2, 3, 5, and 4 via a last_hop channel
2766 // Tests the behaviour when the RouteHint contains a suboptimal hop.
2767 // RouteHint may be partially used by the algo to build the best path.
2769 // First check that last hop can't have its source as the payee.
2770 let invalid_last_hop = RouteHint(vec![RouteHintHop {
2771 src_node_id: nodes[6],
2772 short_channel_id: 8,
2775 proportional_millionths: 0,
2777 cltv_expiry_delta: (8 << 4) | 1,
2778 htlc_minimum_msat: None,
2779 htlc_maximum_msat: None,
2782 let mut invalid_last_hops = last_hops_multi_private_channels(&nodes);
2783 invalid_last_hops.push(invalid_last_hop);
2785 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(invalid_last_hops);
2786 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) {
2787 assert_eq!(err, "Route hint cannot have the payee as the source.");
2788 } else { panic!(); }
2791 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_multi_private_channels(&nodes));
2792 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2793 assert_eq!(route.paths[0].len(), 5);
2795 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2796 assert_eq!(route.paths[0][0].short_channel_id, 2);
2797 assert_eq!(route.paths[0][0].fee_msat, 100);
2798 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2799 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2800 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2802 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2803 assert_eq!(route.paths[0][1].short_channel_id, 4);
2804 assert_eq!(route.paths[0][1].fee_msat, 0);
2805 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2806 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2807 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2809 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2810 assert_eq!(route.paths[0][2].short_channel_id, 6);
2811 assert_eq!(route.paths[0][2].fee_msat, 0);
2812 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2813 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2814 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2816 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2817 assert_eq!(route.paths[0][3].short_channel_id, 11);
2818 assert_eq!(route.paths[0][3].fee_msat, 0);
2819 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2820 // If we have a peer in the node map, we'll use their features here since we don't have
2821 // a way of figuring out their features from the invoice:
2822 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2823 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2825 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2826 assert_eq!(route.paths[0][4].short_channel_id, 8);
2827 assert_eq!(route.paths[0][4].fee_msat, 100);
2828 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2829 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2830 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2833 fn empty_last_hop(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
2834 let zero_fees = RoutingFees {
2836 proportional_millionths: 0,
2838 vec![RouteHint(vec![RouteHintHop {
2839 src_node_id: nodes[3],
2840 short_channel_id: 8,
2842 cltv_expiry_delta: (8 << 4) | 1,
2843 htlc_minimum_msat: None,
2844 htlc_maximum_msat: None,
2845 }]), RouteHint(vec![
2847 ]), RouteHint(vec![RouteHintHop {
2848 src_node_id: nodes[5],
2849 short_channel_id: 10,
2851 cltv_expiry_delta: (10 << 4) | 1,
2852 htlc_minimum_msat: None,
2853 htlc_maximum_msat: None,
2858 fn ignores_empty_last_hops_test() {
2859 let (secp_ctx, network_graph, _, _, logger) = build_graph();
2860 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
2861 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(empty_last_hop(&nodes));
2862 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2863 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2864 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2866 // Test handling of an empty RouteHint passed in Invoice.
2868 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2869 assert_eq!(route.paths[0].len(), 5);
2871 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2872 assert_eq!(route.paths[0][0].short_channel_id, 2);
2873 assert_eq!(route.paths[0][0].fee_msat, 100);
2874 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
2875 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2876 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2878 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2879 assert_eq!(route.paths[0][1].short_channel_id, 4);
2880 assert_eq!(route.paths[0][1].fee_msat, 0);
2881 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
2882 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2883 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2885 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
2886 assert_eq!(route.paths[0][2].short_channel_id, 6);
2887 assert_eq!(route.paths[0][2].fee_msat, 0);
2888 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
2889 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
2890 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
2892 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
2893 assert_eq!(route.paths[0][3].short_channel_id, 11);
2894 assert_eq!(route.paths[0][3].fee_msat, 0);
2895 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
2896 // If we have a peer in the node map, we'll use their features here since we don't have
2897 // a way of figuring out their features from the invoice:
2898 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
2899 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
2901 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
2902 assert_eq!(route.paths[0][4].short_channel_id, 8);
2903 assert_eq!(route.paths[0][4].fee_msat, 100);
2904 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
2905 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
2906 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2909 /// Builds a trivial last-hop hint that passes through the two nodes given, with channel 0xff00
2911 fn multi_hop_last_hops_hint(hint_hops: [PublicKey; 2]) -> Vec<RouteHint> {
2912 let zero_fees = RoutingFees {
2914 proportional_millionths: 0,
2916 vec![RouteHint(vec![RouteHintHop {
2917 src_node_id: hint_hops[0],
2918 short_channel_id: 0xff00,
2921 proportional_millionths: 0,
2923 cltv_expiry_delta: (5 << 4) | 1,
2924 htlc_minimum_msat: None,
2925 htlc_maximum_msat: None,
2927 src_node_id: hint_hops[1],
2928 short_channel_id: 0xff01,
2930 cltv_expiry_delta: (8 << 4) | 1,
2931 htlc_minimum_msat: None,
2932 htlc_maximum_msat: None,
2937 fn multi_hint_last_hops_test() {
2938 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
2939 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
2940 let last_hops = multi_hop_last_hops_hint([nodes[2], nodes[3]]);
2941 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
2942 let scorer = ln_test_utils::TestScorer::with_penalty(0);
2943 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
2944 let random_seed_bytes = keys_manager.get_secure_random_bytes();
2945 // Test through channels 2, 3, 0xff00, 0xff01.
2946 // Test shows that multiple hop hints are considered.
2948 // Disabling channels 6 & 7 by flags=2
2949 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2950 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2951 short_channel_id: 6,
2953 flags: 2, // to disable
2954 cltv_expiry_delta: 0,
2955 htlc_minimum_msat: 0,
2956 htlc_maximum_msat: MAX_VALUE_MSAT,
2958 fee_proportional_millionths: 0,
2959 excess_data: Vec::new()
2961 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
2962 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
2963 short_channel_id: 7,
2965 flags: 2, // to disable
2966 cltv_expiry_delta: 0,
2967 htlc_minimum_msat: 0,
2968 htlc_maximum_msat: MAX_VALUE_MSAT,
2970 fee_proportional_millionths: 0,
2971 excess_data: Vec::new()
2974 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
2975 assert_eq!(route.paths[0].len(), 4);
2977 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
2978 assert_eq!(route.paths[0][0].short_channel_id, 2);
2979 assert_eq!(route.paths[0][0].fee_msat, 200);
2980 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
2981 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
2982 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
2984 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
2985 assert_eq!(route.paths[0][1].short_channel_id, 4);
2986 assert_eq!(route.paths[0][1].fee_msat, 100);
2987 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
2988 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
2989 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
2991 assert_eq!(route.paths[0][2].pubkey, nodes[3]);
2992 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
2993 assert_eq!(route.paths[0][2].fee_msat, 0);
2994 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
2995 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(4));
2996 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
2998 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
2999 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3000 assert_eq!(route.paths[0][3].fee_msat, 100);
3001 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3002 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3003 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3007 fn private_multi_hint_last_hops_test() {
3008 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3009 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3011 let non_announced_privkey = SecretKey::from_slice(&hex::decode(format!("{:02x}", 0xf0).repeat(32)).unwrap()[..]).unwrap();
3012 let non_announced_pubkey = PublicKey::from_secret_key(&secp_ctx, &non_announced_privkey);
3014 let last_hops = multi_hop_last_hops_hint([nodes[2], non_announced_pubkey]);
3015 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3016 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3017 // Test through channels 2, 3, 0xff00, 0xff01.
3018 // Test shows that multiple hop hints are considered.
3020 // Disabling channels 6 & 7 by flags=2
3021 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3022 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3023 short_channel_id: 6,
3025 flags: 2, // to disable
3026 cltv_expiry_delta: 0,
3027 htlc_minimum_msat: 0,
3028 htlc_maximum_msat: MAX_VALUE_MSAT,
3030 fee_proportional_millionths: 0,
3031 excess_data: Vec::new()
3033 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3034 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3035 short_channel_id: 7,
3037 flags: 2, // to disable
3038 cltv_expiry_delta: 0,
3039 htlc_minimum_msat: 0,
3040 htlc_maximum_msat: MAX_VALUE_MSAT,
3042 fee_proportional_millionths: 0,
3043 excess_data: Vec::new()
3046 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &[42u8; 32]).unwrap();
3047 assert_eq!(route.paths[0].len(), 4);
3049 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3050 assert_eq!(route.paths[0][0].short_channel_id, 2);
3051 assert_eq!(route.paths[0][0].fee_msat, 200);
3052 assert_eq!(route.paths[0][0].cltv_expiry_delta, 65);
3053 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3054 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3056 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3057 assert_eq!(route.paths[0][1].short_channel_id, 4);
3058 assert_eq!(route.paths[0][1].fee_msat, 100);
3059 assert_eq!(route.paths[0][1].cltv_expiry_delta, 81);
3060 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3061 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3063 assert_eq!(route.paths[0][2].pubkey, non_announced_pubkey);
3064 assert_eq!(route.paths[0][2].short_channel_id, last_hops[0].0[0].short_channel_id);
3065 assert_eq!(route.paths[0][2].fee_msat, 0);
3066 assert_eq!(route.paths[0][2].cltv_expiry_delta, 129);
3067 assert_eq!(route.paths[0][2].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3068 assert_eq!(route.paths[0][2].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3070 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3071 assert_eq!(route.paths[0][3].short_channel_id, last_hops[0].0[1].short_channel_id);
3072 assert_eq!(route.paths[0][3].fee_msat, 100);
3073 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3074 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3075 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3078 fn last_hops_with_public_channel(nodes: &Vec<PublicKey>) -> Vec<RouteHint> {
3079 let zero_fees = RoutingFees {
3081 proportional_millionths: 0,
3083 vec![RouteHint(vec![RouteHintHop {
3084 src_node_id: nodes[4],
3085 short_channel_id: 11,
3087 cltv_expiry_delta: (11 << 4) | 1,
3088 htlc_minimum_msat: None,
3089 htlc_maximum_msat: None,
3091 src_node_id: nodes[3],
3092 short_channel_id: 8,
3094 cltv_expiry_delta: (8 << 4) | 1,
3095 htlc_minimum_msat: None,
3096 htlc_maximum_msat: None,
3097 }]), RouteHint(vec![RouteHintHop {
3098 src_node_id: nodes[4],
3099 short_channel_id: 9,
3102 proportional_millionths: 0,
3104 cltv_expiry_delta: (9 << 4) | 1,
3105 htlc_minimum_msat: None,
3106 htlc_maximum_msat: None,
3107 }]), RouteHint(vec![RouteHintHop {
3108 src_node_id: nodes[5],
3109 short_channel_id: 10,
3111 cltv_expiry_delta: (10 << 4) | 1,
3112 htlc_minimum_msat: None,
3113 htlc_maximum_msat: None,
3118 fn last_hops_with_public_channel_test() {
3119 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3120 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3121 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops_with_public_channel(&nodes));
3122 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3123 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3124 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3125 // This test shows that public routes can be present in the invoice
3126 // which would be handled in the same manner.
3128 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3129 assert_eq!(route.paths[0].len(), 5);
3131 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3132 assert_eq!(route.paths[0][0].short_channel_id, 2);
3133 assert_eq!(route.paths[0][0].fee_msat, 100);
3134 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3135 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3136 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3138 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3139 assert_eq!(route.paths[0][1].short_channel_id, 4);
3140 assert_eq!(route.paths[0][1].fee_msat, 0);
3141 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3142 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3143 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3145 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3146 assert_eq!(route.paths[0][2].short_channel_id, 6);
3147 assert_eq!(route.paths[0][2].fee_msat, 0);
3148 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3149 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3150 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3152 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3153 assert_eq!(route.paths[0][3].short_channel_id, 11);
3154 assert_eq!(route.paths[0][3].fee_msat, 0);
3155 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3156 // If we have a peer in the node map, we'll use their features here since we don't have
3157 // a way of figuring out their features from the invoice:
3158 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3159 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3161 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3162 assert_eq!(route.paths[0][4].short_channel_id, 8);
3163 assert_eq!(route.paths[0][4].fee_msat, 100);
3164 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3165 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3166 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3170 fn our_chans_last_hop_connect_test() {
3171 let (secp_ctx, network_graph, _, _, logger) = build_graph();
3172 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
3173 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3174 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3175 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3177 // Simple test with outbound channel to 4 to test that last_hops and first_hops connect
3178 let our_chans = vec![get_channel_details(Some(42), nodes[3].clone(), InitFeatures::from_le_bytes(vec![0b11]), 250_000_000)];
3179 let mut last_hops = last_hops(&nodes);
3180 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops.clone());
3181 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();
3182 assert_eq!(route.paths[0].len(), 2);
3184 assert_eq!(route.paths[0][0].pubkey, nodes[3]);
3185 assert_eq!(route.paths[0][0].short_channel_id, 42);
3186 assert_eq!(route.paths[0][0].fee_msat, 0);
3187 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3188 assert_eq!(route.paths[0][0].node_features.le_flags(), &vec![0b11]);
3189 assert_eq!(route.paths[0][0].channel_features.le_flags(), &Vec::<u8>::new()); // No feature flags will meet the relevant-to-channel conversion
3191 assert_eq!(route.paths[0][1].pubkey, nodes[6]);
3192 assert_eq!(route.paths[0][1].short_channel_id, 8);
3193 assert_eq!(route.paths[0][1].fee_msat, 100);
3194 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3195 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3196 assert_eq!(route.paths[0][1].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3198 last_hops[0].0[0].fees.base_msat = 1000;
3200 // Revert to via 6 as the fee on 8 goes up
3201 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops);
3202 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3203 assert_eq!(route.paths[0].len(), 4);
3205 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3206 assert_eq!(route.paths[0][0].short_channel_id, 2);
3207 assert_eq!(route.paths[0][0].fee_msat, 200); // fee increased as its % of value transferred across node
3208 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3209 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3210 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3212 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3213 assert_eq!(route.paths[0][1].short_channel_id, 4);
3214 assert_eq!(route.paths[0][1].fee_msat, 100);
3215 assert_eq!(route.paths[0][1].cltv_expiry_delta, (7 << 4) | 1);
3216 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3217 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3219 assert_eq!(route.paths[0][2].pubkey, nodes[5]);
3220 assert_eq!(route.paths[0][2].short_channel_id, 7);
3221 assert_eq!(route.paths[0][2].fee_msat, 0);
3222 assert_eq!(route.paths[0][2].cltv_expiry_delta, (10 << 4) | 1);
3223 // If we have a peer in the node map, we'll use their features here since we don't have
3224 // a way of figuring out their features from the invoice:
3225 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
3226 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(7));
3228 assert_eq!(route.paths[0][3].pubkey, nodes[6]);
3229 assert_eq!(route.paths[0][3].short_channel_id, 10);
3230 assert_eq!(route.paths[0][3].fee_msat, 100);
3231 assert_eq!(route.paths[0][3].cltv_expiry_delta, 42);
3232 assert_eq!(route.paths[0][3].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3233 assert_eq!(route.paths[0][3].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3235 // ...but still use 8 for larger payments as 6 has a variable feerate
3236 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 2000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3237 assert_eq!(route.paths[0].len(), 5);
3239 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
3240 assert_eq!(route.paths[0][0].short_channel_id, 2);
3241 assert_eq!(route.paths[0][0].fee_msat, 3000);
3242 assert_eq!(route.paths[0][0].cltv_expiry_delta, (4 << 4) | 1);
3243 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(2));
3244 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(2));
3246 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
3247 assert_eq!(route.paths[0][1].short_channel_id, 4);
3248 assert_eq!(route.paths[0][1].fee_msat, 0);
3249 assert_eq!(route.paths[0][1].cltv_expiry_delta, (6 << 4) | 1);
3250 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
3251 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(4));
3253 assert_eq!(route.paths[0][2].pubkey, nodes[4]);
3254 assert_eq!(route.paths[0][2].short_channel_id, 6);
3255 assert_eq!(route.paths[0][2].fee_msat, 0);
3256 assert_eq!(route.paths[0][2].cltv_expiry_delta, (11 << 4) | 1);
3257 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(5));
3258 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(6));
3260 assert_eq!(route.paths[0][3].pubkey, nodes[3]);
3261 assert_eq!(route.paths[0][3].short_channel_id, 11);
3262 assert_eq!(route.paths[0][3].fee_msat, 1000);
3263 assert_eq!(route.paths[0][3].cltv_expiry_delta, (8 << 4) | 1);
3264 // If we have a peer in the node map, we'll use their features here since we don't have
3265 // a way of figuring out their features from the invoice:
3266 assert_eq!(route.paths[0][3].node_features.le_flags(), &id_to_feature_flags(4));
3267 assert_eq!(route.paths[0][3].channel_features.le_flags(), &id_to_feature_flags(11));
3269 assert_eq!(route.paths[0][4].pubkey, nodes[6]);
3270 assert_eq!(route.paths[0][4].short_channel_id, 8);
3271 assert_eq!(route.paths[0][4].fee_msat, 2000);
3272 assert_eq!(route.paths[0][4].cltv_expiry_delta, 42);
3273 assert_eq!(route.paths[0][4].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3274 assert_eq!(route.paths[0][4].channel_features.le_flags(), &Vec::<u8>::new()); // We can't learn any flags from invoices, sadly
3277 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> {
3278 let source_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 41).repeat(32)).unwrap()[..]).unwrap());
3279 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3280 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3282 // If we specify a channel to a middle hop, that overrides our local channel view and that gets used
3283 let last_hops = RouteHint(vec![RouteHintHop {
3284 src_node_id: middle_node_id,
3285 short_channel_id: 8,
3288 proportional_millionths: last_hop_fee_prop,
3290 cltv_expiry_delta: (8 << 4) | 1,
3291 htlc_minimum_msat: None,
3292 htlc_maximum_msat: last_hop_htlc_max,
3294 let payment_params = PaymentParameters::from_node_id(target_node_id).with_route_hints(vec![last_hops]);
3295 let our_chans = vec![get_channel_details(Some(42), middle_node_id, InitFeatures::from_le_bytes(vec![0b11]), outbound_capacity_msat)];
3296 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3297 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3298 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3299 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
3300 let logger = ln_test_utils::TestLogger::new();
3301 let network_graph = NetworkGraph::new(genesis_hash, &logger);
3302 let route = get_route(&source_node_id, &payment_params, &network_graph.read_only(),
3303 Some(&our_chans.iter().collect::<Vec<_>>()), route_val, 42, &logger, &scorer, &random_seed_bytes);
3308 fn unannounced_path_test() {
3309 // We should be able to send a payment to a destination without any help of a routing graph
3310 // if we have a channel with a common counterparty that appears in the first and last hop
3312 let route = do_unannounced_path_test(None, 1, 2000000, 1000000).unwrap();
3314 let middle_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 42).repeat(32)).unwrap()[..]).unwrap());
3315 let target_node_id = PublicKey::from_secret_key(&Secp256k1::new(), &SecretKey::from_slice(&hex::decode(format!("{:02}", 43).repeat(32)).unwrap()[..]).unwrap());
3316 assert_eq!(route.paths[0].len(), 2);
3318 assert_eq!(route.paths[0][0].pubkey, middle_node_id);
3319 assert_eq!(route.paths[0][0].short_channel_id, 42);
3320 assert_eq!(route.paths[0][0].fee_msat, 1001);
3321 assert_eq!(route.paths[0][0].cltv_expiry_delta, (8 << 4) | 1);
3322 assert_eq!(route.paths[0][0].node_features.le_flags(), &[0b11]);
3323 assert_eq!(route.paths[0][0].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3325 assert_eq!(route.paths[0][1].pubkey, target_node_id);
3326 assert_eq!(route.paths[0][1].short_channel_id, 8);
3327 assert_eq!(route.paths[0][1].fee_msat, 1000000);
3328 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
3329 assert_eq!(route.paths[0][1].node_features.le_flags(), default_node_features().le_flags()); // We dont pass flags in from invoices yet
3330 assert_eq!(route.paths[0][1].channel_features.le_flags(), &[0; 0]); // We can't learn any flags from invoices, sadly
3334 fn overflow_unannounced_path_test_liquidity_underflow() {
3335 // Previously, when we had a last-hop hint connected directly to a first-hop channel, where
3336 // the last-hop had a fee which overflowed a u64, we'd panic.
3337 // This was due to us adding the first-hop from us unconditionally, causing us to think
3338 // we'd built a path (as our node is in the "best candidate" set), when we had not.
3339 // In this test, we previously hit a subtraction underflow due to having less available
3340 // liquidity at the last hop than 0.
3341 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());
3345 fn overflow_unannounced_path_test_feerate_overflow() {
3346 // This tests for the same case as above, except instead of hitting a subtraction
3347 // underflow, we hit a case where the fee charged at a hop overflowed.
3348 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());
3352 fn available_amount_while_routing_test() {
3353 // Tests whether we choose the correct available channel amount while routing.
3355 let (secp_ctx, network_graph, mut gossip_sync, chain_monitor, logger) = build_graph();
3356 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3357 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3358 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3359 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3360 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
3362 // We will use a simple single-path route from
3363 // our node to node2 via node0: channels {1, 3}.
3365 // First disable all other paths.
3366 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3367 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3368 short_channel_id: 2,
3371 cltv_expiry_delta: 0,
3372 htlc_minimum_msat: 0,
3373 htlc_maximum_msat: 100_000,
3375 fee_proportional_millionths: 0,
3376 excess_data: Vec::new()
3378 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3379 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3380 short_channel_id: 12,
3383 cltv_expiry_delta: 0,
3384 htlc_minimum_msat: 0,
3385 htlc_maximum_msat: 100_000,
3387 fee_proportional_millionths: 0,
3388 excess_data: Vec::new()
3391 // Make the first channel (#1) very permissive,
3392 // and we will be testing all limits on the second channel.
3393 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3394 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3395 short_channel_id: 1,
3398 cltv_expiry_delta: 0,
3399 htlc_minimum_msat: 0,
3400 htlc_maximum_msat: 1_000_000_000,
3402 fee_proportional_millionths: 0,
3403 excess_data: Vec::new()
3406 // First, let's see if routing works if we have absolutely no idea about the available amount.
3407 // In this case, it should be set to 250_000 sats.
3408 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3409 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3410 short_channel_id: 3,
3413 cltv_expiry_delta: 0,
3414 htlc_minimum_msat: 0,
3415 htlc_maximum_msat: 250_000_000,
3417 fee_proportional_millionths: 0,
3418 excess_data: Vec::new()
3422 // Attempt to route more than available results in a failure.
3423 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3424 &our_id, &payment_params, &network_graph.read_only(), None, 250_000_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3425 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3426 } else { panic!(); }
3430 // Now, attempt to route an exact amount we have should be fine.
3431 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();
3432 assert_eq!(route.paths.len(), 1);
3433 let path = route.paths.last().unwrap();
3434 assert_eq!(path.len(), 2);
3435 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3436 assert_eq!(path.last().unwrap().fee_msat, 250_000_000);
3439 // Check that setting next_outbound_htlc_limit_msat in first_hops limits the channels.
3440 // Disable channel #1 and use another first hop.
3441 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3442 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3443 short_channel_id: 1,
3446 cltv_expiry_delta: 0,
3447 htlc_minimum_msat: 0,
3448 htlc_maximum_msat: 1_000_000_000,
3450 fee_proportional_millionths: 0,
3451 excess_data: Vec::new()
3454 // Now, limit the first_hop by the next_outbound_htlc_limit_msat of 200_000 sats.
3455 let our_chans = vec![get_channel_details(Some(42), nodes[0].clone(), InitFeatures::from_le_bytes(vec![0b11]), 200_000_000)];
3458 // Attempt to route more than available results in a failure.
3459 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3460 &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) {
3461 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3462 } else { panic!(); }
3466 // Now, attempt to route an exact amount we have should be fine.
3467 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();
3468 assert_eq!(route.paths.len(), 1);
3469 let path = route.paths.last().unwrap();
3470 assert_eq!(path.len(), 2);
3471 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3472 assert_eq!(path.last().unwrap().fee_msat, 200_000_000);
3475 // Enable channel #1 back.
3476 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3477 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3478 short_channel_id: 1,
3481 cltv_expiry_delta: 0,
3482 htlc_minimum_msat: 0,
3483 htlc_maximum_msat: 1_000_000_000,
3485 fee_proportional_millionths: 0,
3486 excess_data: Vec::new()
3490 // Now let's see if routing works if we know only htlc_maximum_msat.
3491 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3492 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3493 short_channel_id: 3,
3496 cltv_expiry_delta: 0,
3497 htlc_minimum_msat: 0,
3498 htlc_maximum_msat: 15_000,
3500 fee_proportional_millionths: 0,
3501 excess_data: Vec::new()
3505 // Attempt to route more than available results in a failure.
3506 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3507 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3508 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3509 } else { panic!(); }
3513 // Now, attempt to route an exact amount we have should be fine.
3514 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3515 assert_eq!(route.paths.len(), 1);
3516 let path = route.paths.last().unwrap();
3517 assert_eq!(path.len(), 2);
3518 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3519 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3522 // Now let's see if routing works if we know only capacity from the UTXO.
3524 // We can't change UTXO capacity on the fly, so we'll disable
3525 // the existing channel and add another one with the capacity we need.
3526 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3527 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3528 short_channel_id: 3,
3531 cltv_expiry_delta: 0,
3532 htlc_minimum_msat: 0,
3533 htlc_maximum_msat: MAX_VALUE_MSAT,
3535 fee_proportional_millionths: 0,
3536 excess_data: Vec::new()
3539 let good_script = Builder::new().push_opcode(opcodes::all::OP_PUSHNUM_2)
3540 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[0]).serialize())
3541 .push_slice(&PublicKey::from_secret_key(&secp_ctx, &privkeys[2]).serialize())
3542 .push_opcode(opcodes::all::OP_PUSHNUM_2)
3543 .push_opcode(opcodes::all::OP_CHECKMULTISIG).into_script().to_v0_p2wsh();
3545 *chain_monitor.utxo_ret.lock().unwrap() = Ok(TxOut { value: 15, script_pubkey: good_script.clone() });
3546 gossip_sync.add_chain_access(Some(chain_monitor));
3548 add_channel(&gossip_sync, &secp_ctx, &privkeys[0], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 333);
3549 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3550 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3551 short_channel_id: 333,
3554 cltv_expiry_delta: (3 << 4) | 1,
3555 htlc_minimum_msat: 0,
3556 htlc_maximum_msat: 15_000,
3558 fee_proportional_millionths: 0,
3559 excess_data: Vec::new()
3561 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3562 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3563 short_channel_id: 333,
3566 cltv_expiry_delta: (3 << 4) | 2,
3567 htlc_minimum_msat: 0,
3568 htlc_maximum_msat: 15_000,
3570 fee_proportional_millionths: 0,
3571 excess_data: Vec::new()
3575 // Attempt to route more than available results in a failure.
3576 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3577 &our_id, &payment_params, &network_graph.read_only(), None, 15_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3578 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3579 } else { panic!(); }
3583 // Now, attempt to route an exact amount we have should be fine.
3584 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 15_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3585 assert_eq!(route.paths.len(), 1);
3586 let path = route.paths.last().unwrap();
3587 assert_eq!(path.len(), 2);
3588 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3589 assert_eq!(path.last().unwrap().fee_msat, 15_000);
3592 // Now let's see if routing chooses htlc_maximum_msat over UTXO capacity.
3593 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3594 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3595 short_channel_id: 333,
3598 cltv_expiry_delta: 0,
3599 htlc_minimum_msat: 0,
3600 htlc_maximum_msat: 10_000,
3602 fee_proportional_millionths: 0,
3603 excess_data: Vec::new()
3607 // Attempt to route more than available results in a failure.
3608 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3609 &our_id, &payment_params, &network_graph.read_only(), None, 10_001, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3610 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3611 } else { panic!(); }
3615 // Now, attempt to route an exact amount we have should be fine.
3616 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3617 assert_eq!(route.paths.len(), 1);
3618 let path = route.paths.last().unwrap();
3619 assert_eq!(path.len(), 2);
3620 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3621 assert_eq!(path.last().unwrap().fee_msat, 10_000);
3626 fn available_liquidity_last_hop_test() {
3627 // Check that available liquidity properly limits the path even when only
3628 // one of the latter hops is limited.
3629 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3630 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3631 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3632 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3633 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3634 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3636 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
3637 // {12, 13, 11} have the capacities of 100, {6} has a capacity of 50.
3638 // Total capacity: 50 sats.
3640 // Disable other potential paths.
3641 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3642 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3643 short_channel_id: 2,
3646 cltv_expiry_delta: 0,
3647 htlc_minimum_msat: 0,
3648 htlc_maximum_msat: 100_000,
3650 fee_proportional_millionths: 0,
3651 excess_data: Vec::new()
3653 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3654 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3655 short_channel_id: 7,
3658 cltv_expiry_delta: 0,
3659 htlc_minimum_msat: 0,
3660 htlc_maximum_msat: 100_000,
3662 fee_proportional_millionths: 0,
3663 excess_data: Vec::new()
3668 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3669 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3670 short_channel_id: 12,
3673 cltv_expiry_delta: 0,
3674 htlc_minimum_msat: 0,
3675 htlc_maximum_msat: 100_000,
3677 fee_proportional_millionths: 0,
3678 excess_data: Vec::new()
3680 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3681 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3682 short_channel_id: 13,
3685 cltv_expiry_delta: 0,
3686 htlc_minimum_msat: 0,
3687 htlc_maximum_msat: 100_000,
3689 fee_proportional_millionths: 0,
3690 excess_data: Vec::new()
3693 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3694 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3695 short_channel_id: 6,
3698 cltv_expiry_delta: 0,
3699 htlc_minimum_msat: 0,
3700 htlc_maximum_msat: 50_000,
3702 fee_proportional_millionths: 0,
3703 excess_data: Vec::new()
3705 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
3706 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3707 short_channel_id: 11,
3710 cltv_expiry_delta: 0,
3711 htlc_minimum_msat: 0,
3712 htlc_maximum_msat: 100_000,
3714 fee_proportional_millionths: 0,
3715 excess_data: Vec::new()
3718 // Attempt to route more than available results in a failure.
3719 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3720 &our_id, &payment_params, &network_graph.read_only(), None, 60_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
3721 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3722 } else { panic!(); }
3726 // Now, attempt to route 49 sats (just a bit below the capacity).
3727 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 49_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3728 assert_eq!(route.paths.len(), 1);
3729 let mut total_amount_paid_msat = 0;
3730 for path in &route.paths {
3731 assert_eq!(path.len(), 4);
3732 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3733 total_amount_paid_msat += path.last().unwrap().fee_msat;
3735 assert_eq!(total_amount_paid_msat, 49_000);
3739 // Attempt to route an exact amount is also fine
3740 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3741 assert_eq!(route.paths.len(), 1);
3742 let mut total_amount_paid_msat = 0;
3743 for path in &route.paths {
3744 assert_eq!(path.len(), 4);
3745 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
3746 total_amount_paid_msat += path.last().unwrap().fee_msat;
3748 assert_eq!(total_amount_paid_msat, 50_000);
3753 fn ignore_fee_first_hop_test() {
3754 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3755 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3756 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3757 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3758 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3759 let payment_params = PaymentParameters::from_node_id(nodes[2]);
3761 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3762 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3763 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3764 short_channel_id: 1,
3767 cltv_expiry_delta: 0,
3768 htlc_minimum_msat: 0,
3769 htlc_maximum_msat: 100_000,
3770 fee_base_msat: 1_000_000,
3771 fee_proportional_millionths: 0,
3772 excess_data: Vec::new()
3774 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3775 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3776 short_channel_id: 3,
3779 cltv_expiry_delta: 0,
3780 htlc_minimum_msat: 0,
3781 htlc_maximum_msat: 50_000,
3783 fee_proportional_millionths: 0,
3784 excess_data: Vec::new()
3788 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 50_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3789 assert_eq!(route.paths.len(), 1);
3790 let mut total_amount_paid_msat = 0;
3791 for path in &route.paths {
3792 assert_eq!(path.len(), 2);
3793 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3794 total_amount_paid_msat += path.last().unwrap().fee_msat;
3796 assert_eq!(total_amount_paid_msat, 50_000);
3801 fn simple_mpp_route_test() {
3802 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3803 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3804 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3805 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3806 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3807 let payment_params = PaymentParameters::from_node_id(nodes[2])
3808 .with_features(channelmanager::provided_invoice_features());
3810 // We need a route consisting of 3 paths:
3811 // From our node to node2 via node0, node7, node1 (three paths one hop each).
3812 // To achieve this, the amount being transferred should be around
3813 // the total capacity of these 3 paths.
3815 // First, we set limits on these (previously unlimited) channels.
3816 // Their aggregate capacity will be 50 + 60 + 180 = 290 sats.
3818 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50).
3819 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3820 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3821 short_channel_id: 1,
3824 cltv_expiry_delta: 0,
3825 htlc_minimum_msat: 0,
3826 htlc_maximum_msat: 100_000,
3828 fee_proportional_millionths: 0,
3829 excess_data: Vec::new()
3831 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
3832 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3833 short_channel_id: 3,
3836 cltv_expiry_delta: 0,
3837 htlc_minimum_msat: 0,
3838 htlc_maximum_msat: 50_000,
3840 fee_proportional_millionths: 0,
3841 excess_data: Vec::new()
3844 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats
3845 // (total limit 60).
3846 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3847 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3848 short_channel_id: 12,
3851 cltv_expiry_delta: 0,
3852 htlc_minimum_msat: 0,
3853 htlc_maximum_msat: 60_000,
3855 fee_proportional_millionths: 0,
3856 excess_data: Vec::new()
3858 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
3859 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3860 short_channel_id: 13,
3863 cltv_expiry_delta: 0,
3864 htlc_minimum_msat: 0,
3865 htlc_maximum_msat: 60_000,
3867 fee_proportional_millionths: 0,
3868 excess_data: Vec::new()
3871 // Path via node1 is channels {2, 4}. Limit them to 200 and 180 sats
3872 // (total capacity 180 sats).
3873 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3874 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3875 short_channel_id: 2,
3878 cltv_expiry_delta: 0,
3879 htlc_minimum_msat: 0,
3880 htlc_maximum_msat: 200_000,
3882 fee_proportional_millionths: 0,
3883 excess_data: Vec::new()
3885 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
3886 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3887 short_channel_id: 4,
3890 cltv_expiry_delta: 0,
3891 htlc_minimum_msat: 0,
3892 htlc_maximum_msat: 180_000,
3894 fee_proportional_millionths: 0,
3895 excess_data: Vec::new()
3899 // Attempt to route more than available results in a failure.
3900 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3901 &our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42,
3902 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3903 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3904 } else { panic!(); }
3908 // Attempt to route while setting max_path_count to 0 results in a failure.
3909 let zero_payment_params = payment_params.clone().with_max_path_count(0);
3910 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3911 &our_id, &zero_payment_params, &network_graph.read_only(), None, 100, 42,
3912 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3913 assert_eq!(err, "Can't find a route with no paths allowed.");
3914 } else { panic!(); }
3918 // Attempt to route while setting max_path_count to 3 results in a failure.
3919 // This is the case because the minimal_value_contribution_msat would require each path
3920 // to account for 1/3 of the total value, which is violated by 2 out of 3 paths.
3921 let fail_payment_params = payment_params.clone().with_max_path_count(3);
3922 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
3923 &our_id, &fail_payment_params, &network_graph.read_only(), None, 250_000, 42,
3924 Arc::clone(&logger), &scorer, &random_seed_bytes) {
3925 assert_eq!(err, "Failed to find a sufficient route to the given destination");
3926 } else { panic!(); }
3930 // Now, attempt to route 250 sats (just a bit below the capacity).
3931 // Our algorithm should provide us with these 3 paths.
3932 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3933 250_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3934 assert_eq!(route.paths.len(), 3);
3935 let mut total_amount_paid_msat = 0;
3936 for path in &route.paths {
3937 assert_eq!(path.len(), 2);
3938 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3939 total_amount_paid_msat += path.last().unwrap().fee_msat;
3941 assert_eq!(total_amount_paid_msat, 250_000);
3945 // Attempt to route an exact amount is also fine
3946 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None,
3947 290_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
3948 assert_eq!(route.paths.len(), 3);
3949 let mut total_amount_paid_msat = 0;
3950 for path in &route.paths {
3951 assert_eq!(path.len(), 2);
3952 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
3953 total_amount_paid_msat += path.last().unwrap().fee_msat;
3955 assert_eq!(total_amount_paid_msat, 290_000);
3960 fn long_mpp_route_test() {
3961 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
3962 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
3963 let scorer = ln_test_utils::TestScorer::with_penalty(0);
3964 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
3965 let random_seed_bytes = keys_manager.get_secure_random_bytes();
3966 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
3968 // We need a route consisting of 3 paths:
3969 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
3970 // Note that these paths overlap (channels 5, 12, 13).
3971 // We will route 300 sats.
3972 // Each path will have 100 sats capacity, those channels which
3973 // are used twice will have 200 sats capacity.
3975 // Disable other potential paths.
3976 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
3977 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3978 short_channel_id: 2,
3981 cltv_expiry_delta: 0,
3982 htlc_minimum_msat: 0,
3983 htlc_maximum_msat: 100_000,
3985 fee_proportional_millionths: 0,
3986 excess_data: Vec::new()
3988 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
3989 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
3990 short_channel_id: 7,
3993 cltv_expiry_delta: 0,
3994 htlc_minimum_msat: 0,
3995 htlc_maximum_msat: 100_000,
3997 fee_proportional_millionths: 0,
3998 excess_data: Vec::new()
4001 // Path via {node0, node2} is channels {1, 3, 5}.
4002 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4003 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4004 short_channel_id: 1,
4007 cltv_expiry_delta: 0,
4008 htlc_minimum_msat: 0,
4009 htlc_maximum_msat: 100_000,
4011 fee_proportional_millionths: 0,
4012 excess_data: Vec::new()
4014 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4015 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4016 short_channel_id: 3,
4019 cltv_expiry_delta: 0,
4020 htlc_minimum_msat: 0,
4021 htlc_maximum_msat: 100_000,
4023 fee_proportional_millionths: 0,
4024 excess_data: Vec::new()
4027 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4028 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4029 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4030 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4031 short_channel_id: 5,
4034 cltv_expiry_delta: 0,
4035 htlc_minimum_msat: 0,
4036 htlc_maximum_msat: 200_000,
4038 fee_proportional_millionths: 0,
4039 excess_data: Vec::new()
4042 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4043 // Add 100 sats to the capacities of {12, 13}, because these channels
4044 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4045 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4046 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4047 short_channel_id: 12,
4050 cltv_expiry_delta: 0,
4051 htlc_minimum_msat: 0,
4052 htlc_maximum_msat: 200_000,
4054 fee_proportional_millionths: 0,
4055 excess_data: Vec::new()
4057 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4058 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4059 short_channel_id: 13,
4062 cltv_expiry_delta: 0,
4063 htlc_minimum_msat: 0,
4064 htlc_maximum_msat: 200_000,
4066 fee_proportional_millionths: 0,
4067 excess_data: Vec::new()
4070 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4071 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4072 short_channel_id: 6,
4075 cltv_expiry_delta: 0,
4076 htlc_minimum_msat: 0,
4077 htlc_maximum_msat: 100_000,
4079 fee_proportional_millionths: 0,
4080 excess_data: Vec::new()
4082 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4083 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4084 short_channel_id: 11,
4087 cltv_expiry_delta: 0,
4088 htlc_minimum_msat: 0,
4089 htlc_maximum_msat: 100_000,
4091 fee_proportional_millionths: 0,
4092 excess_data: Vec::new()
4095 // Path via {node7, node2} is channels {12, 13, 5}.
4096 // We already limited them to 200 sats (they are used twice for 100 sats).
4097 // Nothing to do here.
4100 // Attempt to route more than available results in a failure.
4101 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4102 &our_id, &payment_params, &network_graph.read_only(), None, 350_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4103 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4104 } else { panic!(); }
4108 // Now, attempt to route 300 sats (exact amount we can route).
4109 // Our algorithm should provide us with these 3 paths, 100 sats each.
4110 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 300_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4111 assert_eq!(route.paths.len(), 3);
4113 let mut total_amount_paid_msat = 0;
4114 for path in &route.paths {
4115 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4116 total_amount_paid_msat += path.last().unwrap().fee_msat;
4118 assert_eq!(total_amount_paid_msat, 300_000);
4124 fn mpp_cheaper_route_test() {
4125 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4126 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4127 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4128 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4129 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4130 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4132 // This test checks that if we have two cheaper paths and one more expensive path,
4133 // so that liquidity-wise any 2 of 3 combination is sufficient,
4134 // two cheaper paths will be taken.
4135 // These paths have equal available liquidity.
4137 // We need a combination of 3 paths:
4138 // From our node to node3 via {node0, node2}, {node7, node2, node4} and {node7, node2}.
4139 // Note that these paths overlap (channels 5, 12, 13).
4140 // Each path will have 100 sats capacity, those channels which
4141 // are used twice will have 200 sats capacity.
4143 // Disable other potential paths.
4144 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4145 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4146 short_channel_id: 2,
4149 cltv_expiry_delta: 0,
4150 htlc_minimum_msat: 0,
4151 htlc_maximum_msat: 100_000,
4153 fee_proportional_millionths: 0,
4154 excess_data: Vec::new()
4156 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4157 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4158 short_channel_id: 7,
4161 cltv_expiry_delta: 0,
4162 htlc_minimum_msat: 0,
4163 htlc_maximum_msat: 100_000,
4165 fee_proportional_millionths: 0,
4166 excess_data: Vec::new()
4169 // Path via {node0, node2} is channels {1, 3, 5}.
4170 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4171 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4172 short_channel_id: 1,
4175 cltv_expiry_delta: 0,
4176 htlc_minimum_msat: 0,
4177 htlc_maximum_msat: 100_000,
4179 fee_proportional_millionths: 0,
4180 excess_data: Vec::new()
4182 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4183 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4184 short_channel_id: 3,
4187 cltv_expiry_delta: 0,
4188 htlc_minimum_msat: 0,
4189 htlc_maximum_msat: 100_000,
4191 fee_proportional_millionths: 0,
4192 excess_data: Vec::new()
4195 // Capacity of 200 sats because this channel will be used by 3rd path as well.
4196 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4197 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4198 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4199 short_channel_id: 5,
4202 cltv_expiry_delta: 0,
4203 htlc_minimum_msat: 0,
4204 htlc_maximum_msat: 200_000,
4206 fee_proportional_millionths: 0,
4207 excess_data: Vec::new()
4210 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4211 // Add 100 sats to the capacities of {12, 13}, because these channels
4212 // are also used for 3rd path. 100 sats for the rest. Total capacity: 100 sats.
4213 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4214 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4215 short_channel_id: 12,
4218 cltv_expiry_delta: 0,
4219 htlc_minimum_msat: 0,
4220 htlc_maximum_msat: 200_000,
4222 fee_proportional_millionths: 0,
4223 excess_data: Vec::new()
4225 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4226 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4227 short_channel_id: 13,
4230 cltv_expiry_delta: 0,
4231 htlc_minimum_msat: 0,
4232 htlc_maximum_msat: 200_000,
4234 fee_proportional_millionths: 0,
4235 excess_data: Vec::new()
4238 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4239 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4240 short_channel_id: 6,
4243 cltv_expiry_delta: 0,
4244 htlc_minimum_msat: 0,
4245 htlc_maximum_msat: 100_000,
4246 fee_base_msat: 1_000,
4247 fee_proportional_millionths: 0,
4248 excess_data: Vec::new()
4250 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4251 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4252 short_channel_id: 11,
4255 cltv_expiry_delta: 0,
4256 htlc_minimum_msat: 0,
4257 htlc_maximum_msat: 100_000,
4259 fee_proportional_millionths: 0,
4260 excess_data: Vec::new()
4263 // Path via {node7, node2} is channels {12, 13, 5}.
4264 // We already limited them to 200 sats (they are used twice for 100 sats).
4265 // Nothing to do here.
4268 // Now, attempt to route 180 sats.
4269 // Our algorithm should provide us with these 2 paths.
4270 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 180_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4271 assert_eq!(route.paths.len(), 2);
4273 let mut total_value_transferred_msat = 0;
4274 let mut total_paid_msat = 0;
4275 for path in &route.paths {
4276 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4277 total_value_transferred_msat += path.last().unwrap().fee_msat;
4279 total_paid_msat += hop.fee_msat;
4282 // If we paid fee, this would be higher.
4283 assert_eq!(total_value_transferred_msat, 180_000);
4284 let total_fees_paid = total_paid_msat - total_value_transferred_msat;
4285 assert_eq!(total_fees_paid, 0);
4290 fn fees_on_mpp_route_test() {
4291 // This test makes sure that MPP algorithm properly takes into account
4292 // fees charged on the channels, by making the fees impactful:
4293 // if the fee is not properly accounted for, the behavior is different.
4294 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4295 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4296 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4297 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4298 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4299 let payment_params = PaymentParameters::from_node_id(nodes[3]).with_features(channelmanager::provided_invoice_features());
4301 // We need a route consisting of 2 paths:
4302 // From our node to node3 via {node0, node2} and {node7, node2, node4}.
4303 // We will route 200 sats, Each path will have 100 sats capacity.
4305 // This test is not particularly stable: e.g.,
4306 // there's a way to route via {node0, node2, node4}.
4307 // It works while pathfinding is deterministic, but can be broken otherwise.
4308 // It's fine to ignore this concern for now.
4310 // Disable other potential paths.
4311 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4312 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4313 short_channel_id: 2,
4316 cltv_expiry_delta: 0,
4317 htlc_minimum_msat: 0,
4318 htlc_maximum_msat: 100_000,
4320 fee_proportional_millionths: 0,
4321 excess_data: Vec::new()
4324 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4325 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4326 short_channel_id: 7,
4329 cltv_expiry_delta: 0,
4330 htlc_minimum_msat: 0,
4331 htlc_maximum_msat: 100_000,
4333 fee_proportional_millionths: 0,
4334 excess_data: Vec::new()
4337 // Path via {node0, node2} is channels {1, 3, 5}.
4338 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4339 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4340 short_channel_id: 1,
4343 cltv_expiry_delta: 0,
4344 htlc_minimum_msat: 0,
4345 htlc_maximum_msat: 100_000,
4347 fee_proportional_millionths: 0,
4348 excess_data: Vec::new()
4350 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4351 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4352 short_channel_id: 3,
4355 cltv_expiry_delta: 0,
4356 htlc_minimum_msat: 0,
4357 htlc_maximum_msat: 100_000,
4359 fee_proportional_millionths: 0,
4360 excess_data: Vec::new()
4363 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4364 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4365 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4366 short_channel_id: 5,
4369 cltv_expiry_delta: 0,
4370 htlc_minimum_msat: 0,
4371 htlc_maximum_msat: 100_000,
4373 fee_proportional_millionths: 0,
4374 excess_data: Vec::new()
4377 // Path via {node7, node2, node4} is channels {12, 13, 6, 11}.
4378 // All channels should be 100 sats capacity. But for the fee experiment,
4379 // we'll add absolute fee of 150 sats paid for the use channel 6 (paid to node2 on channel 13).
4380 // Since channel 12 allows to deliver only 250 sats to channel 13, channel 13 can transfer only
4381 // 100 sats (and pay 150 sats in fees for the use of channel 6),
4382 // so no matter how large are other channels,
4383 // the whole path will be limited by 100 sats with just these 2 conditions:
4384 // - channel 12 capacity is 250 sats
4385 // - fee for channel 6 is 150 sats
4386 // Let's test this by enforcing these 2 conditions and removing other limits.
4387 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4388 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4389 short_channel_id: 12,
4392 cltv_expiry_delta: 0,
4393 htlc_minimum_msat: 0,
4394 htlc_maximum_msat: 250_000,
4396 fee_proportional_millionths: 0,
4397 excess_data: Vec::new()
4399 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4400 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4401 short_channel_id: 13,
4404 cltv_expiry_delta: 0,
4405 htlc_minimum_msat: 0,
4406 htlc_maximum_msat: MAX_VALUE_MSAT,
4408 fee_proportional_millionths: 0,
4409 excess_data: Vec::new()
4412 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4413 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4414 short_channel_id: 6,
4417 cltv_expiry_delta: 0,
4418 htlc_minimum_msat: 0,
4419 htlc_maximum_msat: MAX_VALUE_MSAT,
4420 fee_base_msat: 150_000,
4421 fee_proportional_millionths: 0,
4422 excess_data: Vec::new()
4424 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4425 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4426 short_channel_id: 11,
4429 cltv_expiry_delta: 0,
4430 htlc_minimum_msat: 0,
4431 htlc_maximum_msat: MAX_VALUE_MSAT,
4433 fee_proportional_millionths: 0,
4434 excess_data: Vec::new()
4438 // Attempt to route more than available results in a failure.
4439 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4440 &our_id, &payment_params, &network_graph.read_only(), None, 210_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4441 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4442 } else { panic!(); }
4446 // Now, attempt to route 200 sats (exact amount we can route).
4447 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 200_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4448 assert_eq!(route.paths.len(), 2);
4450 let mut total_amount_paid_msat = 0;
4451 for path in &route.paths {
4452 assert_eq!(path.last().unwrap().pubkey, nodes[3]);
4453 total_amount_paid_msat += path.last().unwrap().fee_msat;
4455 assert_eq!(total_amount_paid_msat, 200_000);
4456 assert_eq!(route.get_total_fees(), 150_000);
4461 fn mpp_with_last_hops() {
4462 // Previously, if we tried to send an MPP payment to a destination which was only reachable
4463 // via a single last-hop route hint, we'd fail to route if we first collected routes
4464 // totaling close but not quite enough to fund the full payment.
4466 // This was because we considered last-hop hints to have exactly the sought payment amount
4467 // instead of the amount we were trying to collect, needlessly limiting our path searching
4468 // at the very first hop.
4470 // Specifically, this interacted with our "all paths must fund at least 5% of total target"
4471 // criterion to cause us to refuse all routes at the last hop hint which would be considered
4472 // to only have the remaining to-collect amount in available liquidity.
4474 // This bug appeared in production in some specific channel configurations.
4475 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4476 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4477 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4478 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4479 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4480 let payment_params = PaymentParameters::from_node_id(PublicKey::from_slice(&[02; 33]).unwrap()).with_features(channelmanager::provided_invoice_features())
4481 .with_route_hints(vec![RouteHint(vec![RouteHintHop {
4482 src_node_id: nodes[2],
4483 short_channel_id: 42,
4484 fees: RoutingFees { base_msat: 0, proportional_millionths: 0 },
4485 cltv_expiry_delta: 42,
4486 htlc_minimum_msat: None,
4487 htlc_maximum_msat: None,
4488 }])]).with_max_channel_saturation_power_of_half(0);
4490 // Keep only two paths from us to nodes[2], both with a 99sat HTLC maximum, with one with
4491 // no fee and one with a 1msat fee. Previously, trying to route 100 sats to nodes[2] here
4492 // would first use the no-fee route and then fail to find a path along the second route as
4493 // we think we can only send up to 1 additional sat over the last-hop but refuse to as its
4494 // under 5% of our payment amount.
4495 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4496 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4497 short_channel_id: 1,
4500 cltv_expiry_delta: (5 << 4) | 5,
4501 htlc_minimum_msat: 0,
4502 htlc_maximum_msat: 99_000,
4503 fee_base_msat: u32::max_value(),
4504 fee_proportional_millionths: u32::max_value(),
4505 excess_data: Vec::new()
4507 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4508 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4509 short_channel_id: 2,
4512 cltv_expiry_delta: (5 << 4) | 3,
4513 htlc_minimum_msat: 0,
4514 htlc_maximum_msat: 99_000,
4515 fee_base_msat: u32::max_value(),
4516 fee_proportional_millionths: u32::max_value(),
4517 excess_data: Vec::new()
4519 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4520 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4521 short_channel_id: 4,
4524 cltv_expiry_delta: (4 << 4) | 1,
4525 htlc_minimum_msat: 0,
4526 htlc_maximum_msat: MAX_VALUE_MSAT,
4528 fee_proportional_millionths: 0,
4529 excess_data: Vec::new()
4531 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4532 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4533 short_channel_id: 13,
4535 flags: 0|2, // Channel disabled
4536 cltv_expiry_delta: (13 << 4) | 1,
4537 htlc_minimum_msat: 0,
4538 htlc_maximum_msat: MAX_VALUE_MSAT,
4540 fee_proportional_millionths: 2000000,
4541 excess_data: Vec::new()
4544 // Get a route for 100 sats and check that we found the MPP route no problem and didn't
4546 let mut route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4547 assert_eq!(route.paths.len(), 2);
4548 route.paths.sort_by_key(|path| path[0].short_channel_id);
4549 // Paths are manually ordered ordered by SCID, so:
4550 // * the first is channel 1 (0 fee, but 99 sat maximum) -> channel 3 -> channel 42
4551 // * the second is channel 2 (1 msat fee) -> channel 4 -> channel 42
4552 assert_eq!(route.paths[0][0].short_channel_id, 1);
4553 assert_eq!(route.paths[0][0].fee_msat, 0);
4554 assert_eq!(route.paths[0][2].fee_msat, 99_000);
4555 assert_eq!(route.paths[1][0].short_channel_id, 2);
4556 assert_eq!(route.paths[1][0].fee_msat, 1);
4557 assert_eq!(route.paths[1][2].fee_msat, 1_000);
4558 assert_eq!(route.get_total_fees(), 1);
4559 assert_eq!(route.get_total_amount(), 100_000);
4563 fn drop_lowest_channel_mpp_route_test() {
4564 // This test checks that low-capacity channel is dropped when after
4565 // path finding we realize that we found more capacity than we need.
4566 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4567 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4568 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4569 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4570 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4571 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features())
4572 .with_max_channel_saturation_power_of_half(0);
4574 // We need a route consisting of 3 paths:
4575 // From our node to node2 via node0, node7, node1 (three paths one hop each).
4577 // The first and the second paths should be sufficient, but the third should be
4578 // cheaper, so that we select it but drop later.
4580 // First, we set limits on these (previously unlimited) channels.
4581 // Their aggregate capacity will be 50 + 60 + 20 = 130 sats.
4583 // Path via node0 is channels {1, 3}. Limit them to 100 and 50 sats (total limit 50);
4584 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4585 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4586 short_channel_id: 1,
4589 cltv_expiry_delta: 0,
4590 htlc_minimum_msat: 0,
4591 htlc_maximum_msat: 100_000,
4593 fee_proportional_millionths: 0,
4594 excess_data: Vec::new()
4596 update_channel(&gossip_sync, &secp_ctx, &privkeys[0], UnsignedChannelUpdate {
4597 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4598 short_channel_id: 3,
4601 cltv_expiry_delta: 0,
4602 htlc_minimum_msat: 0,
4603 htlc_maximum_msat: 50_000,
4605 fee_proportional_millionths: 0,
4606 excess_data: Vec::new()
4609 // Path via node7 is channels {12, 13}. Limit them to 60 and 60 sats (total limit 60);
4610 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4611 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4612 short_channel_id: 12,
4615 cltv_expiry_delta: 0,
4616 htlc_minimum_msat: 0,
4617 htlc_maximum_msat: 60_000,
4619 fee_proportional_millionths: 0,
4620 excess_data: Vec::new()
4622 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
4623 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4624 short_channel_id: 13,
4627 cltv_expiry_delta: 0,
4628 htlc_minimum_msat: 0,
4629 htlc_maximum_msat: 60_000,
4631 fee_proportional_millionths: 0,
4632 excess_data: Vec::new()
4635 // Path via node1 is channels {2, 4}. Limit them to 20 and 20 sats (total capacity 20 sats).
4636 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4637 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4638 short_channel_id: 2,
4641 cltv_expiry_delta: 0,
4642 htlc_minimum_msat: 0,
4643 htlc_maximum_msat: 20_000,
4645 fee_proportional_millionths: 0,
4646 excess_data: Vec::new()
4648 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4649 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4650 short_channel_id: 4,
4653 cltv_expiry_delta: 0,
4654 htlc_minimum_msat: 0,
4655 htlc_maximum_msat: 20_000,
4657 fee_proportional_millionths: 0,
4658 excess_data: Vec::new()
4662 // Attempt to route more than available results in a failure.
4663 if let Err(LightningError{err, action: ErrorAction::IgnoreError}) = get_route(
4664 &our_id, &payment_params, &network_graph.read_only(), None, 150_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes) {
4665 assert_eq!(err, "Failed to find a sufficient route to the given destination");
4666 } else { panic!(); }
4670 // Now, attempt to route 125 sats (just a bit below the capacity of 3 channels).
4671 // Our algorithm should provide us with these 3 paths.
4672 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 125_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4673 assert_eq!(route.paths.len(), 3);
4674 let mut total_amount_paid_msat = 0;
4675 for path in &route.paths {
4676 assert_eq!(path.len(), 2);
4677 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4678 total_amount_paid_msat += path.last().unwrap().fee_msat;
4680 assert_eq!(total_amount_paid_msat, 125_000);
4684 // Attempt to route without the last small cheap channel
4685 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4686 assert_eq!(route.paths.len(), 2);
4687 let mut total_amount_paid_msat = 0;
4688 for path in &route.paths {
4689 assert_eq!(path.len(), 2);
4690 assert_eq!(path.last().unwrap().pubkey, nodes[2]);
4691 total_amount_paid_msat += path.last().unwrap().fee_msat;
4693 assert_eq!(total_amount_paid_msat, 90_000);
4698 fn min_criteria_consistency() {
4699 // Test that we don't use an inconsistent metric between updating and walking nodes during
4700 // our Dijkstra's pass. In the initial version of MPP, the "best source" for a given node
4701 // was updated with a different criterion from the heap sorting, resulting in loops in
4702 // calculated paths. We test for that specific case here.
4704 // We construct a network that looks like this:
4706 // node2 -1(3)2- node3
4710 // node1 -1(5)2- node4 -1(1)2- node6
4716 // We create a loop on the side of our real path - our destination is node 6, with a
4717 // previous hop of node 4. From 4, the cheapest previous path is channel 2 from node 2,
4718 // followed by node 3 over channel 3. Thereafter, the cheapest next-hop is back to node 4
4719 // (this time over channel 4). Channel 4 has 0 htlc_minimum_msat whereas channel 1 (the
4720 // other channel with a previous-hop of node 4) has a high (but irrelevant to the overall
4721 // payment) htlc_minimum_msat. In the original algorithm, this resulted in node4's
4722 // "previous hop" being set to node 3, creating a loop in the path.
4723 let secp_ctx = Secp256k1::new();
4724 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4725 let logger = Arc::new(ln_test_utils::TestLogger::new());
4726 let network = Arc::new(NetworkGraph::new(genesis_hash, Arc::clone(&logger)));
4727 let gossip_sync = P2PGossipSync::new(Arc::clone(&network), None, Arc::clone(&logger));
4728 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4729 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4730 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4731 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4732 let payment_params = PaymentParameters::from_node_id(nodes[6]);
4734 add_channel(&gossip_sync, &secp_ctx, &our_privkey, &privkeys[1], ChannelFeatures::from_le_bytes(id_to_feature_flags(6)), 6);
4735 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4736 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4737 short_channel_id: 6,
4740 cltv_expiry_delta: (6 << 4) | 0,
4741 htlc_minimum_msat: 0,
4742 htlc_maximum_msat: MAX_VALUE_MSAT,
4744 fee_proportional_millionths: 0,
4745 excess_data: Vec::new()
4747 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[1], NodeFeatures::from_le_bytes(id_to_feature_flags(1)), 0);
4749 add_channel(&gossip_sync, &secp_ctx, &privkeys[1], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(5)), 5);
4750 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4751 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4752 short_channel_id: 5,
4755 cltv_expiry_delta: (5 << 4) | 0,
4756 htlc_minimum_msat: 0,
4757 htlc_maximum_msat: MAX_VALUE_MSAT,
4759 fee_proportional_millionths: 0,
4760 excess_data: Vec::new()
4762 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[4], NodeFeatures::from_le_bytes(id_to_feature_flags(4)), 0);
4764 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[3], ChannelFeatures::from_le_bytes(id_to_feature_flags(4)), 4);
4765 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4766 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4767 short_channel_id: 4,
4770 cltv_expiry_delta: (4 << 4) | 0,
4771 htlc_minimum_msat: 0,
4772 htlc_maximum_msat: MAX_VALUE_MSAT,
4774 fee_proportional_millionths: 0,
4775 excess_data: Vec::new()
4777 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[3], NodeFeatures::from_le_bytes(id_to_feature_flags(3)), 0);
4779 add_channel(&gossip_sync, &secp_ctx, &privkeys[3], &privkeys[2], ChannelFeatures::from_le_bytes(id_to_feature_flags(3)), 3);
4780 update_channel(&gossip_sync, &secp_ctx, &privkeys[3], UnsignedChannelUpdate {
4781 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4782 short_channel_id: 3,
4785 cltv_expiry_delta: (3 << 4) | 0,
4786 htlc_minimum_msat: 0,
4787 htlc_maximum_msat: MAX_VALUE_MSAT,
4789 fee_proportional_millionths: 0,
4790 excess_data: Vec::new()
4792 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[2], NodeFeatures::from_le_bytes(id_to_feature_flags(2)), 0);
4794 add_channel(&gossip_sync, &secp_ctx, &privkeys[2], &privkeys[4], ChannelFeatures::from_le_bytes(id_to_feature_flags(2)), 2);
4795 update_channel(&gossip_sync, &secp_ctx, &privkeys[2], UnsignedChannelUpdate {
4796 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4797 short_channel_id: 2,
4800 cltv_expiry_delta: (2 << 4) | 0,
4801 htlc_minimum_msat: 0,
4802 htlc_maximum_msat: MAX_VALUE_MSAT,
4804 fee_proportional_millionths: 0,
4805 excess_data: Vec::new()
4808 add_channel(&gossip_sync, &secp_ctx, &privkeys[4], &privkeys[6], ChannelFeatures::from_le_bytes(id_to_feature_flags(1)), 1);
4809 update_channel(&gossip_sync, &secp_ctx, &privkeys[4], UnsignedChannelUpdate {
4810 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4811 short_channel_id: 1,
4814 cltv_expiry_delta: (1 << 4) | 0,
4815 htlc_minimum_msat: 100,
4816 htlc_maximum_msat: MAX_VALUE_MSAT,
4818 fee_proportional_millionths: 0,
4819 excess_data: Vec::new()
4821 add_or_update_node(&gossip_sync, &secp_ctx, &privkeys[6], NodeFeatures::from_le_bytes(id_to_feature_flags(6)), 0);
4824 // Now ensure the route flows simply over nodes 1 and 4 to 6.
4825 let route = get_route(&our_id, &payment_params, &network.read_only(), None, 10_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4826 assert_eq!(route.paths.len(), 1);
4827 assert_eq!(route.paths[0].len(), 3);
4829 assert_eq!(route.paths[0][0].pubkey, nodes[1]);
4830 assert_eq!(route.paths[0][0].short_channel_id, 6);
4831 assert_eq!(route.paths[0][0].fee_msat, 100);
4832 assert_eq!(route.paths[0][0].cltv_expiry_delta, (5 << 4) | 0);
4833 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(1));
4834 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(6));
4836 assert_eq!(route.paths[0][1].pubkey, nodes[4]);
4837 assert_eq!(route.paths[0][1].short_channel_id, 5);
4838 assert_eq!(route.paths[0][1].fee_msat, 0);
4839 assert_eq!(route.paths[0][1].cltv_expiry_delta, (1 << 4) | 0);
4840 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(4));
4841 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(5));
4843 assert_eq!(route.paths[0][2].pubkey, nodes[6]);
4844 assert_eq!(route.paths[0][2].short_channel_id, 1);
4845 assert_eq!(route.paths[0][2].fee_msat, 10_000);
4846 assert_eq!(route.paths[0][2].cltv_expiry_delta, 42);
4847 assert_eq!(route.paths[0][2].node_features.le_flags(), &id_to_feature_flags(6));
4848 assert_eq!(route.paths[0][2].channel_features.le_flags(), &id_to_feature_flags(1));
4854 fn exact_fee_liquidity_limit() {
4855 // Test that if, while walking the graph, we find a hop that has exactly enough liquidity
4856 // for us, including later hop fees, we take it. In the first version of our MPP algorithm
4857 // we calculated fees on a higher value, resulting in us ignoring such paths.
4858 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4859 let (our_privkey, our_id, _, nodes) = get_nodes(&secp_ctx);
4860 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4861 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4862 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4863 let payment_params = PaymentParameters::from_node_id(nodes[2]);
4865 // We modify the graph to set the htlc_maximum of channel 2 to below the value we wish to
4867 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4868 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4869 short_channel_id: 2,
4872 cltv_expiry_delta: 0,
4873 htlc_minimum_msat: 0,
4874 htlc_maximum_msat: 85_000,
4876 fee_proportional_millionths: 0,
4877 excess_data: Vec::new()
4880 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4881 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4882 short_channel_id: 12,
4885 cltv_expiry_delta: (4 << 4) | 1,
4886 htlc_minimum_msat: 0,
4887 htlc_maximum_msat: 270_000,
4889 fee_proportional_millionths: 1000000,
4890 excess_data: Vec::new()
4894 // Now, attempt to route 90 sats, which is exactly 90 sats at the last hop, plus the
4895 // 200% fee charged channel 13 in the 1-to-2 direction.
4896 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4897 assert_eq!(route.paths.len(), 1);
4898 assert_eq!(route.paths[0].len(), 2);
4900 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4901 assert_eq!(route.paths[0][0].short_channel_id, 12);
4902 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4903 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4904 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4905 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4907 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4908 assert_eq!(route.paths[0][1].short_channel_id, 13);
4909 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4910 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4911 assert_eq!(route.paths[0][1].node_features.le_flags(), &id_to_feature_flags(3));
4912 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4917 fn htlc_max_reduction_below_min() {
4918 // Test that if, while walking the graph, we reduce the value being sent to meet an
4919 // htlc_maximum_msat, we don't end up undershooting a later htlc_minimum_msat. In the
4920 // initial version of MPP we'd accept such routes but reject them while recalculating fees,
4921 // resulting in us thinking there is no possible path, even if other paths exist.
4922 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
4923 let (our_privkey, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
4924 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4925 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4926 let random_seed_bytes = keys_manager.get_secure_random_bytes();
4927 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
4929 // We modify the graph to set the htlc_minimum of channel 2 and 4 as needed - channel 2
4930 // gets an htlc_maximum_msat of 80_000 and channel 4 an htlc_minimum_msat of 90_000. We
4931 // then try to send 90_000.
4932 update_channel(&gossip_sync, &secp_ctx, &our_privkey, UnsignedChannelUpdate {
4933 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4934 short_channel_id: 2,
4937 cltv_expiry_delta: 0,
4938 htlc_minimum_msat: 0,
4939 htlc_maximum_msat: 80_000,
4941 fee_proportional_millionths: 0,
4942 excess_data: Vec::new()
4944 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
4945 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
4946 short_channel_id: 4,
4949 cltv_expiry_delta: (4 << 4) | 1,
4950 htlc_minimum_msat: 90_000,
4951 htlc_maximum_msat: MAX_VALUE_MSAT,
4953 fee_proportional_millionths: 0,
4954 excess_data: Vec::new()
4958 // Now, attempt to route 90 sats, hitting the htlc_minimum on channel 4, but
4959 // overshooting the htlc_maximum on channel 2. Thus, we should pick the (absurdly
4960 // expensive) channels 12-13 path.
4961 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 90_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
4962 assert_eq!(route.paths.len(), 1);
4963 assert_eq!(route.paths[0].len(), 2);
4965 assert_eq!(route.paths[0][0].pubkey, nodes[7]);
4966 assert_eq!(route.paths[0][0].short_channel_id, 12);
4967 assert_eq!(route.paths[0][0].fee_msat, 90_000*2);
4968 assert_eq!(route.paths[0][0].cltv_expiry_delta, (13 << 4) | 1);
4969 assert_eq!(route.paths[0][0].node_features.le_flags(), &id_to_feature_flags(8));
4970 assert_eq!(route.paths[0][0].channel_features.le_flags(), &id_to_feature_flags(12));
4972 assert_eq!(route.paths[0][1].pubkey, nodes[2]);
4973 assert_eq!(route.paths[0][1].short_channel_id, 13);
4974 assert_eq!(route.paths[0][1].fee_msat, 90_000);
4975 assert_eq!(route.paths[0][1].cltv_expiry_delta, 42);
4976 assert_eq!(route.paths[0][1].node_features.le_flags(), channelmanager::provided_invoice_features().le_flags());
4977 assert_eq!(route.paths[0][1].channel_features.le_flags(), &id_to_feature_flags(13));
4982 fn multiple_direct_first_hops() {
4983 // Previously we'd only ever considered one first hop path per counterparty.
4984 // However, as we don't restrict users to one channel per peer, we really need to support
4985 // looking at all first hop paths.
4986 // Here we test that we do not ignore all-but-the-last first hop paths per counterparty (as
4987 // we used to do by overwriting the `first_hop_targets` hashmap entry) and that we can MPP
4988 // route over multiple channels with the same first hop.
4989 let secp_ctx = Secp256k1::new();
4990 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
4991 let genesis_hash = genesis_block(Network::Testnet).header.block_hash();
4992 let logger = Arc::new(ln_test_utils::TestLogger::new());
4993 let network_graph = NetworkGraph::new(genesis_hash, Arc::clone(&logger));
4994 let scorer = ln_test_utils::TestScorer::with_penalty(0);
4995 let payment_params = PaymentParameters::from_node_id(nodes[0]).with_features(channelmanager::provided_invoice_features());
4996 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
4997 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5000 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5001 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 200_000),
5002 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 10_000),
5003 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5004 assert_eq!(route.paths.len(), 1);
5005 assert_eq!(route.paths[0].len(), 1);
5007 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5008 assert_eq!(route.paths[0][0].short_channel_id, 3);
5009 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5012 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5013 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
5014 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
5015 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5016 assert_eq!(route.paths.len(), 2);
5017 assert_eq!(route.paths[0].len(), 1);
5018 assert_eq!(route.paths[1].len(), 1);
5020 assert!((route.paths[0][0].short_channel_id == 3 && route.paths[1][0].short_channel_id == 2) ||
5021 (route.paths[0][0].short_channel_id == 2 && route.paths[1][0].short_channel_id == 3));
5023 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5024 assert_eq!(route.paths[0][0].fee_msat, 50_000);
5026 assert_eq!(route.paths[1][0].pubkey, nodes[0]);
5027 assert_eq!(route.paths[1][0].fee_msat, 50_000);
5031 // If we have a bunch of outbound channels to the same node, where most are not
5032 // sufficient to pay the full payment, but one is, we should default to just using the
5033 // one single channel that has sufficient balance, avoiding MPP.
5035 // If we have several options above the 3xpayment value threshold, we should pick the
5036 // smallest of them, avoiding further fragmenting our available outbound balance to
5038 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), Some(&[
5039 &get_channel_details(Some(2), nodes[0], channelmanager::provided_init_features(), 50_000),
5040 &get_channel_details(Some(3), nodes[0], channelmanager::provided_init_features(), 50_000),
5041 &get_channel_details(Some(5), nodes[0], channelmanager::provided_init_features(), 50_000),
5042 &get_channel_details(Some(6), nodes[0], channelmanager::provided_init_features(), 300_000),
5043 &get_channel_details(Some(7), nodes[0], channelmanager::provided_init_features(), 50_000),
5044 &get_channel_details(Some(8), nodes[0], channelmanager::provided_init_features(), 50_000),
5045 &get_channel_details(Some(9), nodes[0], channelmanager::provided_init_features(), 50_000),
5046 &get_channel_details(Some(4), nodes[0], channelmanager::provided_init_features(), 1_000_000),
5047 ]), 100_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5048 assert_eq!(route.paths.len(), 1);
5049 assert_eq!(route.paths[0].len(), 1);
5051 assert_eq!(route.paths[0][0].pubkey, nodes[0]);
5052 assert_eq!(route.paths[0][0].short_channel_id, 6);
5053 assert_eq!(route.paths[0][0].fee_msat, 100_000);
5058 fn prefers_shorter_route_with_higher_fees() {
5059 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5060 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5061 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5063 // Without penalizing each hop 100 msats, a longer path with lower fees is chosen.
5064 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5065 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5066 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5067 let route = get_route(
5068 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5069 Arc::clone(&logger), &scorer, &random_seed_bytes
5071 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5073 assert_eq!(route.get_total_fees(), 100);
5074 assert_eq!(route.get_total_amount(), 100);
5075 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5077 // Applying a 100 msat penalty to each hop results in taking channels 7 and 10 to nodes[6]
5078 // from nodes[2] rather than channel 6, 11, and 8, even though the longer path is cheaper.
5079 let scorer = ln_test_utils::TestScorer::with_penalty(100);
5080 let route = get_route(
5081 &our_id, &payment_params, &network_graph.read_only(), None, 100, 42,
5082 Arc::clone(&logger), &scorer, &random_seed_bytes
5084 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5086 assert_eq!(route.get_total_fees(), 300);
5087 assert_eq!(route.get_total_amount(), 100);
5088 assert_eq!(path, vec![2, 4, 7, 10]);
5091 struct BadChannelScorer {
5092 short_channel_id: u64,
5096 impl Writeable for BadChannelScorer {
5097 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5099 impl Score for BadChannelScorer {
5100 fn channel_penalty_msat(&self, short_channel_id: u64, _: &NodeId, _: &NodeId, _: ChannelUsage) -> u64 {
5101 if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 }
5104 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5105 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5106 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5107 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5110 struct BadNodeScorer {
5115 impl Writeable for BadNodeScorer {
5116 fn write<W: Writer>(&self, _w: &mut W) -> Result<(), crate::io::Error> { unimplemented!() }
5119 impl Score for BadNodeScorer {
5120 fn channel_penalty_msat(&self, _: u64, _: &NodeId, target: &NodeId, _: ChannelUsage) -> u64 {
5121 if *target == self.node_id { u64::max_value() } else { 0 }
5124 fn payment_path_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5125 fn payment_path_successful(&mut self, _path: &[&RouteHop]) {}
5126 fn probe_failed(&mut self, _path: &[&RouteHop], _short_channel_id: u64) {}
5127 fn probe_successful(&mut self, _path: &[&RouteHop]) {}
5131 fn avoids_routing_through_bad_channels_and_nodes() {
5132 let (secp_ctx, network, _, _, logger) = build_graph();
5133 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5134 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5135 let network_graph = network.read_only();
5137 // A path to nodes[6] exists when no penalties are applied to any channel.
5138 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5139 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5140 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5141 let route = get_route(
5142 &our_id, &payment_params, &network_graph, None, 100, 42,
5143 Arc::clone(&logger), &scorer, &random_seed_bytes
5145 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5147 assert_eq!(route.get_total_fees(), 100);
5148 assert_eq!(route.get_total_amount(), 100);
5149 assert_eq!(path, vec![2, 4, 6, 11, 8]);
5151 // A different path to nodes[6] exists if channel 6 cannot be routed over.
5152 let scorer = BadChannelScorer { short_channel_id: 6 };
5153 let route = get_route(
5154 &our_id, &payment_params, &network_graph, None, 100, 42,
5155 Arc::clone(&logger), &scorer, &random_seed_bytes
5157 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5159 assert_eq!(route.get_total_fees(), 300);
5160 assert_eq!(route.get_total_amount(), 100);
5161 assert_eq!(path, vec![2, 4, 7, 10]);
5163 // A path to nodes[6] does not exist if nodes[2] cannot be routed through.
5164 let scorer = BadNodeScorer { node_id: NodeId::from_pubkey(&nodes[2]) };
5166 &our_id, &payment_params, &network_graph, None, 100, 42,
5167 Arc::clone(&logger), &scorer, &random_seed_bytes
5169 Err(LightningError { err, .. } ) => {
5170 assert_eq!(err, "Failed to find a path to the given destination");
5172 Ok(_) => panic!("Expected error"),
5177 fn total_fees_single_path() {
5181 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5182 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5183 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5186 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5187 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5188 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5191 pubkey: PublicKey::from_slice(&hex::decode("027f31ebc5462c1fdce1b737ecff52d37d75dea43ce11c74d25aa297165faa2007").unwrap()[..]).unwrap(),
5192 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5193 short_channel_id: 0, fee_msat: 225, cltv_expiry_delta: 0
5196 payment_params: None,
5199 assert_eq!(route.get_total_fees(), 250);
5200 assert_eq!(route.get_total_amount(), 225);
5204 fn total_fees_multi_path() {
5208 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5209 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5210 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5213 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5214 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5215 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5219 pubkey: PublicKey::from_slice(&hex::decode("02eec7245d6b7d2ccb30380bfbe2a3648cd7a942653f5aa340edcea1f283686619").unwrap()[..]).unwrap(),
5220 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5221 short_channel_id: 0, fee_msat: 100, cltv_expiry_delta: 0
5224 pubkey: PublicKey::from_slice(&hex::decode("0324653eac434488002cc06bbfb7f10fe18991e35f9fe4302dbea6d2353dc0ab1c").unwrap()[..]).unwrap(),
5225 channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
5226 short_channel_id: 0, fee_msat: 150, cltv_expiry_delta: 0
5229 payment_params: None,
5232 assert_eq!(route.get_total_fees(), 200);
5233 assert_eq!(route.get_total_amount(), 300);
5237 fn total_empty_route_no_panic() {
5238 // In an earlier version of `Route::get_total_fees` and `Route::get_total_amount`, they
5239 // would both panic if the route was completely empty. We test to ensure they return 0
5240 // here, even though its somewhat nonsensical as a route.
5241 let route = Route { paths: Vec::new(), payment_params: None };
5243 assert_eq!(route.get_total_fees(), 0);
5244 assert_eq!(route.get_total_amount(), 0);
5248 fn limits_total_cltv_delta() {
5249 let (secp_ctx, network, _, _, logger) = build_graph();
5250 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5251 let network_graph = network.read_only();
5253 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5255 // Make sure that generally there is at least one route available
5256 let feasible_max_total_cltv_delta = 1008;
5257 let feasible_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5258 .with_max_total_cltv_expiry_delta(feasible_max_total_cltv_delta);
5259 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5260 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5261 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5262 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5263 assert_ne!(path.len(), 0);
5265 // But not if we exclude all paths on the basis of their accumulated CLTV delta
5266 let fail_max_total_cltv_delta = 23;
5267 let fail_payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5268 .with_max_total_cltv_expiry_delta(fail_max_total_cltv_delta);
5269 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes)
5271 Err(LightningError { err, .. } ) => {
5272 assert_eq!(err, "Failed to find a path to the given destination");
5274 Ok(_) => panic!("Expected error"),
5279 fn avoids_recently_failed_paths() {
5280 // Ensure that the router always avoids all of the `previously_failed_channels` channels by
5281 // randomly inserting channels into it until we can't find a route anymore.
5282 let (secp_ctx, network, _, _, logger) = build_graph();
5283 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5284 let network_graph = network.read_only();
5286 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5287 let mut payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes))
5288 .with_max_path_count(1);
5289 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5290 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5292 // We should be able to find a route initially, and then after we fail a few random
5293 // channels eventually we won't be able to any longer.
5294 assert!(get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes).is_ok());
5296 if let Ok(route) = get_route(&our_id, &payment_params, &network_graph, None, 100, 0, Arc::clone(&logger), &scorer, &random_seed_bytes) {
5297 for chan in route.paths[0].iter() {
5298 assert!(!payment_params.previously_failed_channels.contains(&chan.short_channel_id));
5300 let victim = (u64::from_ne_bytes(random_seed_bytes[0..8].try_into().unwrap()) as usize)
5301 % route.paths[0].len();
5302 payment_params.previously_failed_channels.push(route.paths[0][victim].short_channel_id);
5308 fn limits_path_length() {
5309 let (secp_ctx, network, _, _, logger) = build_line_graph();
5310 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5311 let network_graph = network.read_only();
5313 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5314 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5315 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5317 // First check we can actually create a long route on this graph.
5318 let feasible_payment_params = PaymentParameters::from_node_id(nodes[18]);
5319 let route = get_route(&our_id, &feasible_payment_params, &network_graph, None, 100, 0,
5320 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5321 let path = route.paths[0].iter().map(|hop| hop.short_channel_id).collect::<Vec<_>>();
5322 assert!(path.len() == MAX_PATH_LENGTH_ESTIMATE.into());
5324 // But we can't create a path surpassing the MAX_PATH_LENGTH_ESTIMATE limit.
5325 let fail_payment_params = PaymentParameters::from_node_id(nodes[19]);
5326 match get_route(&our_id, &fail_payment_params, &network_graph, None, 100, 0,
5327 Arc::clone(&logger), &scorer, &random_seed_bytes)
5329 Err(LightningError { err, .. } ) => {
5330 assert_eq!(err, "Failed to find a path to the given destination");
5332 Ok(_) => panic!("Expected error"),
5337 fn adds_and_limits_cltv_offset() {
5338 let (secp_ctx, network_graph, _, _, logger) = build_graph();
5339 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5341 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5343 let payment_params = PaymentParameters::from_node_id(nodes[6]).with_route_hints(last_hops(&nodes));
5344 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5345 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5346 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5347 assert_eq!(route.paths.len(), 1);
5349 let cltv_expiry_deltas_before = route.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5351 // Check whether the offset added to the last hop by default is in [1 .. DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA]
5352 let mut route_default = route.clone();
5353 add_random_cltv_offset(&mut route_default, &payment_params, &network_graph.read_only(), &random_seed_bytes);
5354 let cltv_expiry_deltas_default = route_default.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5355 assert_eq!(cltv_expiry_deltas_before.split_last().unwrap().1, cltv_expiry_deltas_default.split_last().unwrap().1);
5356 assert!(cltv_expiry_deltas_default.last() > cltv_expiry_deltas_before.last());
5357 assert!(cltv_expiry_deltas_default.last().unwrap() <= &DEFAULT_MAX_TOTAL_CLTV_EXPIRY_DELTA);
5359 // Check that no offset is added when we restrict the max_total_cltv_expiry_delta
5360 let mut route_limited = route.clone();
5361 let limited_max_total_cltv_expiry_delta = cltv_expiry_deltas_before.iter().sum();
5362 let limited_payment_params = payment_params.with_max_total_cltv_expiry_delta(limited_max_total_cltv_expiry_delta);
5363 add_random_cltv_offset(&mut route_limited, &limited_payment_params, &network_graph.read_only(), &random_seed_bytes);
5364 let cltv_expiry_deltas_limited = route_limited.paths[0].iter().map(|h| h.cltv_expiry_delta).collect::<Vec<u32>>();
5365 assert_eq!(cltv_expiry_deltas_before, cltv_expiry_deltas_limited);
5369 fn adds_plausible_cltv_offset() {
5370 let (secp_ctx, network, _, _, logger) = build_graph();
5371 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5372 let network_graph = network.read_only();
5373 let network_nodes = network_graph.nodes();
5374 let network_channels = network_graph.channels();
5375 let scorer = ln_test_utils::TestScorer::with_penalty(0);
5376 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5377 let keys_manager = ln_test_utils::TestKeysInterface::new(&[4u8; 32], Network::Testnet);
5378 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5380 let mut route = get_route(&our_id, &payment_params, &network_graph, None, 100, 0,
5381 Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5382 add_random_cltv_offset(&mut route, &payment_params, &network_graph, &random_seed_bytes);
5384 let mut path_plausibility = vec![];
5386 for p in route.paths {
5387 // 1. Select random observation point
5388 let mut prng = ChaCha20::new(&random_seed_bytes, &[0u8; 12]);
5389 let mut random_bytes = [0u8; ::core::mem::size_of::<usize>()];
5391 prng.process_in_place(&mut random_bytes);
5392 let random_path_index = usize::from_be_bytes(random_bytes).wrapping_rem(p.len());
5393 let observation_point = NodeId::from_pubkey(&p.get(random_path_index).unwrap().pubkey);
5395 // 2. Calculate what CLTV expiry delta we would observe there
5396 let observed_cltv_expiry_delta: u32 = p[random_path_index..].iter().map(|h| h.cltv_expiry_delta).sum();
5398 // 3. Starting from the observation point, find candidate paths
5399 let mut candidates: VecDeque<(NodeId, Vec<u32>)> = VecDeque::new();
5400 candidates.push_back((observation_point, vec![]));
5402 let mut found_plausible_candidate = false;
5404 'candidate_loop: while let Some((cur_node_id, cur_path_cltv_deltas)) = candidates.pop_front() {
5405 if let Some(remaining) = observed_cltv_expiry_delta.checked_sub(cur_path_cltv_deltas.iter().sum::<u32>()) {
5406 if remaining == 0 || remaining.wrapping_rem(40) == 0 || remaining.wrapping_rem(144) == 0 {
5407 found_plausible_candidate = true;
5408 break 'candidate_loop;
5412 if let Some(cur_node) = network_nodes.get(&cur_node_id) {
5413 for channel_id in &cur_node.channels {
5414 if let Some(channel_info) = network_channels.get(&channel_id) {
5415 if let Some((dir_info, next_id)) = channel_info.as_directed_from(&cur_node_id) {
5416 let next_cltv_expiry_delta = dir_info.direction().cltv_expiry_delta as u32;
5417 if cur_path_cltv_deltas.iter().sum::<u32>()
5418 .saturating_add(next_cltv_expiry_delta) <= observed_cltv_expiry_delta {
5419 let mut new_path_cltv_deltas = cur_path_cltv_deltas.clone();
5420 new_path_cltv_deltas.push(next_cltv_expiry_delta);
5421 candidates.push_back((*next_id, new_path_cltv_deltas));
5429 path_plausibility.push(found_plausible_candidate);
5431 assert!(path_plausibility.iter().all(|x| *x));
5435 fn builds_correct_path_from_hops() {
5436 let (secp_ctx, network, _, _, logger) = build_graph();
5437 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5438 let network_graph = network.read_only();
5440 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5441 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5443 let payment_params = PaymentParameters::from_node_id(nodes[3]);
5444 let hops = [nodes[1], nodes[2], nodes[4], nodes[3]];
5445 let route = build_route_from_hops_internal(&our_id, &hops, &payment_params,
5446 &network_graph, 100, 0, Arc::clone(&logger), &random_seed_bytes).unwrap();
5447 let route_hop_pubkeys = route.paths[0].iter().map(|hop| hop.pubkey).collect::<Vec<_>>();
5448 assert_eq!(hops.len(), route.paths[0].len());
5449 for (idx, hop_pubkey) in hops.iter().enumerate() {
5450 assert!(*hop_pubkey == route_hop_pubkeys[idx]);
5455 fn avoids_saturating_channels() {
5456 let (secp_ctx, network_graph, gossip_sync, _, logger) = build_graph();
5457 let (_, our_id, privkeys, nodes) = get_nodes(&secp_ctx);
5459 let scorer = ProbabilisticScorer::new(Default::default(), &*network_graph, Arc::clone(&logger));
5461 // Set the fee on channel 13 to 100% to match channel 4 giving us two equivalent paths (us
5462 // -> node 7 -> node2 and us -> node 1 -> node 2) which we should balance over.
5463 update_channel(&gossip_sync, &secp_ctx, &privkeys[1], UnsignedChannelUpdate {
5464 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5465 short_channel_id: 4,
5468 cltv_expiry_delta: (4 << 4) | 1,
5469 htlc_minimum_msat: 0,
5470 htlc_maximum_msat: 250_000_000,
5472 fee_proportional_millionths: 0,
5473 excess_data: Vec::new()
5475 update_channel(&gossip_sync, &secp_ctx, &privkeys[7], UnsignedChannelUpdate {
5476 chain_hash: genesis_block(Network::Testnet).header.block_hash(),
5477 short_channel_id: 13,
5480 cltv_expiry_delta: (13 << 4) | 1,
5481 htlc_minimum_msat: 0,
5482 htlc_maximum_msat: 250_000_000,
5484 fee_proportional_millionths: 0,
5485 excess_data: Vec::new()
5488 let payment_params = PaymentParameters::from_node_id(nodes[2]).with_features(channelmanager::provided_invoice_features());
5489 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5490 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5491 // 100,000 sats is less than the available liquidity on each channel, set above.
5492 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100_000_000, 42, Arc::clone(&logger), &scorer, &random_seed_bytes).unwrap();
5493 assert_eq!(route.paths.len(), 2);
5494 assert!((route.paths[0][1].short_channel_id == 4 && route.paths[1][1].short_channel_id == 13) ||
5495 (route.paths[1][1].short_channel_id == 4 && route.paths[0][1].short_channel_id == 13));
5498 #[cfg(not(feature = "no-std"))]
5499 pub(super) fn random_init_seed() -> u64 {
5500 // Because the default HashMap in std pulls OS randomness, we can use it as a (bad) RNG.
5501 use core::hash::{BuildHasher, Hasher};
5502 let seed = std::collections::hash_map::RandomState::new().build_hasher().finish();
5503 println!("Using seed of {}", seed);
5506 #[cfg(not(feature = "no-std"))]
5507 use crate::util::ser::ReadableArgs;
5510 #[cfg(not(feature = "no-std"))]
5511 fn generate_routes() {
5512 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5514 let mut d = match super::bench_utils::get_route_file() {
5521 let logger = ln_test_utils::TestLogger::new();
5522 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5523 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5524 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5526 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5527 let mut seed = random_init_seed() as usize;
5528 let nodes = graph.read_only().nodes().clone();
5529 'load_endpoints: for _ in 0..10 {
5531 seed = seed.overflowing_mul(0xdeadbeef).0;
5532 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5533 seed = seed.overflowing_mul(0xdeadbeef).0;
5534 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5535 let payment_params = PaymentParameters::from_node_id(dst);
5536 let amt = seed as u64 % 200_000_000;
5537 let params = ProbabilisticScoringParameters::default();
5538 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5539 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5540 continue 'load_endpoints;
5547 #[cfg(not(feature = "no-std"))]
5548 fn generate_routes_mpp() {
5549 use crate::routing::scoring::{ProbabilisticScorer, ProbabilisticScoringParameters};
5551 let mut d = match super::bench_utils::get_route_file() {
5558 let logger = ln_test_utils::TestLogger::new();
5559 let graph = NetworkGraph::read(&mut d, &logger).unwrap();
5560 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5561 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5563 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5564 let mut seed = random_init_seed() as usize;
5565 let nodes = graph.read_only().nodes().clone();
5566 'load_endpoints: for _ in 0..10 {
5568 seed = seed.overflowing_mul(0xdeadbeef).0;
5569 let src = &PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5570 seed = seed.overflowing_mul(0xdeadbeef).0;
5571 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5572 let payment_params = PaymentParameters::from_node_id(dst).with_features(channelmanager::provided_invoice_features());
5573 let amt = seed as u64 % 200_000_000;
5574 let params = ProbabilisticScoringParameters::default();
5575 let scorer = ProbabilisticScorer::new(params, &graph, &logger);
5576 if get_route(src, &payment_params, &graph.read_only(), None, amt, 42, &logger, &scorer, &random_seed_bytes).is_ok() {
5577 continue 'load_endpoints;
5584 fn honors_manual_penalties() {
5585 let (secp_ctx, network_graph, _, _, logger) = build_line_graph();
5586 let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
5588 let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
5589 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5591 let scorer_params = ProbabilisticScoringParameters::default();
5592 let mut scorer = ProbabilisticScorer::new(scorer_params, Arc::clone(&network_graph), Arc::clone(&logger));
5594 // First check set manual penalties are returned by the scorer.
5595 let usage = ChannelUsage {
5597 inflight_htlc_msat: 0,
5598 effective_capacity: EffectiveCapacity::Total { capacity_msat: 1_024_000, htlc_maximum_msat: 1_000 },
5600 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[3]), 123);
5601 scorer.set_manual_penalty(&NodeId::from_pubkey(&nodes[4]), 456);
5602 assert_eq!(scorer.channel_penalty_msat(42, &NodeId::from_pubkey(&nodes[3]), &NodeId::from_pubkey(&nodes[4]), usage), 456);
5604 // Then check we can get a normal route
5605 let payment_params = PaymentParameters::from_node_id(nodes[10]);
5606 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5607 assert!(route.is_ok());
5609 // Then check that we can't get a route if we ban an intermediate node.
5610 scorer.add_banned(&NodeId::from_pubkey(&nodes[3]));
5611 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5612 assert!(route.is_err());
5614 // Finally make sure we can route again, when we remove the ban.
5615 scorer.remove_banned(&NodeId::from_pubkey(&nodes[3]));
5616 let route = get_route(&our_id, &payment_params, &network_graph.read_only(), None, 100, 42, Arc::clone(&logger), &scorer, &random_seed_bytes);
5617 assert!(route.is_ok());
5621 #[cfg(all(test, not(feature = "no-std")))]
5622 pub(crate) mod bench_utils {
5624 /// Tries to open a network graph file, or panics with a URL to fetch it.
5625 pub(crate) fn get_route_file() -> Result<std::fs::File, &'static str> {
5626 let res = File::open("net_graph-2021-05-31.bin") // By default we're run in RL/lightning
5627 .or_else(|_| File::open("lightning/net_graph-2021-05-31.bin")) // We may be run manually in RL/
5628 .or_else(|_| { // Fall back to guessing based on the binary location
5629 // path is likely something like .../rust-lightning/target/debug/deps/lightning-...
5630 let mut path = std::env::current_exe().unwrap();
5631 path.pop(); // lightning-...
5633 path.pop(); // debug
5634 path.pop(); // target
5635 path.push("lightning");
5636 path.push("net_graph-2021-05-31.bin");
5637 eprintln!("{}", path.to_str().unwrap());
5640 .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");
5641 #[cfg(require_route_graph_test)]
5642 return Ok(res.unwrap());
5643 #[cfg(not(require_route_graph_test))]
5648 #[cfg(all(test, feature = "_bench_unstable", not(feature = "no-std")))]
5651 use bitcoin::hashes::Hash;
5652 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
5653 use crate::chain::transaction::OutPoint;
5654 use crate::chain::keysinterface::{KeysManager,KeysInterface};
5655 use crate::ln::channelmanager::{self, ChannelCounterparty, ChannelDetails};
5656 use crate::ln::features::InvoiceFeatures;
5657 use crate::routing::gossip::NetworkGraph;
5658 use crate::routing::scoring::{FixedPenaltyScorer, ProbabilisticScorer, ProbabilisticScoringParameters};
5659 use crate::util::logger::{Logger, Record};
5660 use crate::util::ser::ReadableArgs;
5664 struct DummyLogger {}
5665 impl Logger for DummyLogger {
5666 fn log(&self, _record: &Record) {}
5669 fn read_network_graph(logger: &DummyLogger) -> NetworkGraph<&DummyLogger> {
5670 let mut d = bench_utils::get_route_file().unwrap();
5671 NetworkGraph::read(&mut d, logger).unwrap()
5674 fn payer_pubkey() -> PublicKey {
5675 let secp_ctx = Secp256k1::new();
5676 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap())
5680 fn first_hop(node_id: PublicKey) -> ChannelDetails {
5682 channel_id: [0; 32],
5683 counterparty: ChannelCounterparty {
5684 features: channelmanager::provided_init_features(),
5686 unspendable_punishment_reserve: 0,
5687 forwarding_info: None,
5688 outbound_htlc_minimum_msat: None,
5689 outbound_htlc_maximum_msat: None,
5691 funding_txo: Some(OutPoint {
5692 txid: bitcoin::Txid::from_slice(&[0; 32]).unwrap(), index: 0
5695 short_channel_id: Some(1),
5696 inbound_scid_alias: None,
5697 outbound_scid_alias: None,
5698 channel_value_satoshis: 10_000_000,
5700 balance_msat: 10_000_000,
5701 outbound_capacity_msat: 10_000_000,
5702 next_outbound_htlc_limit_msat: 10_000_000,
5703 inbound_capacity_msat: 0,
5704 unspendable_punishment_reserve: None,
5705 confirmations_required: None,
5706 force_close_spend_delay: None,
5708 is_channel_ready: true,
5711 inbound_htlc_minimum_msat: None,
5712 inbound_htlc_maximum_msat: None,
5718 fn generate_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5719 let logger = DummyLogger {};
5720 let network_graph = read_network_graph(&logger);
5721 let scorer = FixedPenaltyScorer::with_penalty(0);
5722 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5726 fn generate_mpp_routes_with_zero_penalty_scorer(bench: &mut Bencher) {
5727 let logger = DummyLogger {};
5728 let network_graph = read_network_graph(&logger);
5729 let scorer = FixedPenaltyScorer::with_penalty(0);
5730 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
5734 fn generate_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5735 let logger = DummyLogger {};
5736 let network_graph = read_network_graph(&logger);
5737 let params = ProbabilisticScoringParameters::default();
5738 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5739 generate_routes(bench, &network_graph, scorer, InvoiceFeatures::empty());
5743 fn generate_mpp_routes_with_probabilistic_scorer(bench: &mut Bencher) {
5744 let logger = DummyLogger {};
5745 let network_graph = read_network_graph(&logger);
5746 let params = ProbabilisticScoringParameters::default();
5747 let scorer = ProbabilisticScorer::new(params, &network_graph, &logger);
5748 generate_routes(bench, &network_graph, scorer, channelmanager::provided_invoice_features());
5751 fn generate_routes<S: Score>(
5752 bench: &mut Bencher, graph: &NetworkGraph<&DummyLogger>, mut scorer: S,
5753 features: InvoiceFeatures
5755 let nodes = graph.read_only().nodes().clone();
5756 let payer = payer_pubkey();
5757 let keys_manager = KeysManager::new(&[0u8; 32], 42, 42);
5758 let random_seed_bytes = keys_manager.get_secure_random_bytes();
5760 // First, get 100 (source, destination) pairs for which route-getting actually succeeds...
5761 let mut routes = Vec::new();
5762 let mut route_endpoints = Vec::new();
5763 let mut seed: usize = 0xdeadbeef;
5764 'load_endpoints: for _ in 0..150 {
5767 let src = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5769 let dst = PublicKey::from_slice(nodes.keys().skip(seed % nodes.len()).next().unwrap().as_slice()).unwrap();
5770 let params = PaymentParameters::from_node_id(dst).with_features(features.clone());
5771 let first_hop = first_hop(src);
5772 let amt = seed as u64 % 1_000_000;
5773 if let Ok(route) = get_route(&payer, ¶ms, &graph.read_only(), Some(&[&first_hop]), amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes) {
5775 route_endpoints.push((first_hop, params, amt));
5776 continue 'load_endpoints;
5781 // ...and seed the scorer with success and failure data...
5782 for route in routes {
5783 let amount = route.get_total_amount();
5784 if amount < 250_000 {
5785 for path in route.paths {
5786 scorer.payment_path_successful(&path.iter().collect::<Vec<_>>());
5788 } else if amount > 750_000 {
5789 for path in route.paths {
5790 let short_channel_id = path[path.len() / 2].short_channel_id;
5791 scorer.payment_path_failed(&path.iter().collect::<Vec<_>>(), short_channel_id);
5796 // Because we've changed channel scores, its possible we'll take different routes to the
5797 // selected destinations, possibly causing us to fail because, eg, the newly-selected path
5798 // requires a too-high CLTV delta.
5799 route_endpoints.retain(|(first_hop, params, amt)| {
5800 get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok()
5802 route_endpoints.truncate(100);
5803 assert_eq!(route_endpoints.len(), 100);
5805 // ...then benchmark finding paths between the nodes we learned.
5808 let (first_hop, params, amt) = &route_endpoints[idx % route_endpoints.len()];
5809 assert!(get_route(&payer, params, &graph.read_only(), Some(&[first_hop]), *amt, 42, &DummyLogger{}, &scorer, &random_seed_bytes).is_ok());