From: Jeffrey Czyz Date: Thu, 14 Oct 2021 18:04:39 +0000 (-0500) Subject: Notify scorer of failing payment path and channel X-Git-Tag: v0.0.103~5^2~2 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=7a8954e1ca318eecb4a03aa5f729d9d0ee9a904e;p=rust-lightning Notify scorer of failing payment path and channel Upon receiving a PaymentPathFailed event, the failing payment may be retried on a different path. To avoid using the channel responsible for the failure, a scorer should be notified of the failure before being used to find a new route. Add a payment_path_failed method to routing::Score and call it in InvoicePayer's event handler. Introduce a LockableScore parameterization to InvoicePayer so the scorer is locked only once before calling find_route. --- diff --git a/lightning-background-processor/src/lib.rs b/lightning-background-processor/src/lib.rs index e38a4a97..16c5eb4f 100644 --- a/lightning-background-processor/src/lib.rs +++ b/lightning-background-processor/src/lib.rs @@ -311,6 +311,7 @@ mod tests { use lightning::ln::features::InitFeatures; use lightning::ln::msgs::{ChannelMessageHandler, Init}; use lightning::ln::peer_handler::{PeerManager, MessageHandler, SocketDescriptor, IgnoringMessageHandler}; + use lightning::routing::scorer::Scorer; use lightning::routing::network_graph::{NetworkGraph, NetGraphMsgHandler}; use lightning::util::config::UserConfig; use lightning::util::events::{Event, MessageSendEventsProvider, MessageSendEvent}; diff --git a/lightning-invoice/src/payment.rs b/lightning-invoice/src/payment.rs index 7e931d66..ba260742 100644 --- a/lightning-invoice/src/payment.rs +++ b/lightning-invoice/src/payment.rs @@ -30,12 +30,15 @@ //! # use lightning::ln::{PaymentHash, PaymentSecret}; //! # use lightning::ln::channelmanager::{ChannelDetails, PaymentId, PaymentSendFailure}; //! # use lightning::ln::msgs::LightningError; -//! # use lightning::routing::router::{Route, RouteParameters}; +//! # use lightning::routing; +//! # use lightning::routing::network_graph::NodeId; +//! # use lightning::routing::router::{Route, RouteHop, RouteParameters}; //! # use lightning::util::events::{Event, EventHandler, EventsProvider}; //! # use lightning::util::logger::{Logger, Record}; //! # use lightning_invoice::Invoice; //! # use lightning_invoice::payment::{InvoicePayer, Payer, RetryAttempts, Router}; //! # use secp256k1::key::PublicKey; +//! # use std::cell::RefCell; //! # use std::ops::Deref; //! # //! # struct FakeEventProvider {} @@ -56,13 +59,21 @@ //! # } //! # //! # struct FakeRouter {}; -//! # impl Router for FakeRouter { +//! # impl Router for FakeRouter { //! # fn find_route( //! # &self, payer: &PublicKey, params: &RouteParameters, -//! # first_hops: Option<&[&ChannelDetails]> +//! # first_hops: Option<&[&ChannelDetails]>, scorer: &S //! # ) -> Result { unimplemented!() } //! # } //! # +//! # struct FakeScorer {}; +//! # impl routing::Score for FakeScorer { +//! # fn channel_penalty_msat( +//! # &self, _short_channel_id: u64, _source: &NodeId, _target: &NodeId +//! # ) -> u64 { 0 } +//! # fn payment_path_failed(&mut self, _path: &Vec, _short_channel_id: u64) {} +//! # } +//! # //! # struct FakeLogger {}; //! # impl Logger for FakeLogger { //! # fn log(&self, record: &Record) { unimplemented!() } @@ -78,8 +89,9 @@ //! }; //! # let payer = FakePayer {}; //! # let router = FakeRouter {}; +//! # let scorer = RefCell::new(FakeScorer {}); //! # let logger = FakeLogger {}; -//! let invoice_payer = InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); +//! let invoice_payer = InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); //! //! let invoice = "..."; //! let invoice = invoice.parse::().unwrap(); @@ -105,6 +117,8 @@ use bitcoin_hashes::Hash; use lightning::ln::{PaymentHash, PaymentSecret}; use lightning::ln::channelmanager::{ChannelDetails, PaymentId, PaymentSendFailure}; use lightning::ln::msgs::LightningError; +use lightning::routing; +use lightning::routing::{LockableScore, Score}; use lightning::routing::router::{Payee, Route, RouteParameters}; use lightning::util::events::{Event, EventHandler}; use lightning::util::logger::Logger; @@ -117,15 +131,17 @@ use std::sync::Mutex; use std::time::{Duration, SystemTime}; /// A utility for paying [`Invoice]`s. -pub struct InvoicePayer +pub struct InvoicePayer where P::Target: Payer, - R: Router, + R: for <'a> Router<<::Target as routing::LockableScore<'a>>::Locked>, + S::Target: for <'a> routing::LockableScore<'a>, L::Target: Logger, E: EventHandler, { payer: P, router: R, + scorer: S, logger: L, event_handler: E, payment_cache: Mutex>, @@ -150,10 +166,11 @@ pub trait Payer { } /// A trait defining behavior for routing an [`Invoice`] payment. -pub trait Router { +pub trait Router { /// Finds a [`Route`] between `payer` and `payee` for a payment with the given values. fn find_route( - &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]> + &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]>, + scorer: &S ) -> Result; } @@ -172,10 +189,11 @@ pub enum PaymentError { Sending(PaymentSendFailure), } -impl InvoicePayer +impl InvoicePayer where P::Target: Payer, - R: Router, + R: for <'a> Router<<::Target as routing::LockableScore<'a>>::Locked>, + S::Target: for <'a> routing::LockableScore<'a>, L::Target: Logger, E: EventHandler, { @@ -184,11 +202,12 @@ where /// Will forward any [`Event::PaymentPathFailed`] events to the decorated `event_handler` once /// `retry_attempts` has been exceeded for a given [`Invoice`]. pub fn new( - payer: P, router: R, logger: L, event_handler: E, retry_attempts: RetryAttempts + payer: P, router: R, scorer: S, logger: L, event_handler: E, retry_attempts: RetryAttempts ) -> Self { Self { payer, router, + scorer, logger, event_handler, payment_cache: Mutex::new(HashMap::new()), @@ -242,6 +261,7 @@ where &payer, ¶ms, Some(&first_hops.iter().collect::>()), + &self.scorer.lock(), ).map_err(|e| PaymentError::Routing(e))?; let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner()); @@ -261,7 +281,8 @@ where let payer = self.payer.node_id(); let first_hops = self.payer.first_hops(); let route = self.router.find_route( - &payer, ¶ms, Some(&first_hops.iter().collect::>()) + &payer, ¶ms, Some(&first_hops.iter().collect::>()), + &self.scorer.lock() ).map_err(|e| PaymentError::Routing(e))?; self.payer.retry_payment(&route, payment_id).map_err(|e| PaymentError::Sending(e)) } @@ -284,16 +305,23 @@ fn has_expired(params: &RouteParameters) -> bool { Invoice::is_expired_from_epoch(&SystemTime::UNIX_EPOCH, expiry_time) } -impl EventHandler for InvoicePayer +impl EventHandler for InvoicePayer where P::Target: Payer, - R: Router, + R: for <'a> Router<<::Target as routing::LockableScore<'a>>::Locked>, + S::Target: for <'a> routing::LockableScore<'a>, L::Target: Logger, E: EventHandler, { fn handle_event(&self, event: &Event) { match event { - Event::PaymentPathFailed { payment_id, payment_hash, rejected_by_dest, retry, .. } => { + Event::PaymentPathFailed { + payment_id, payment_hash, rejected_by_dest, path, short_channel_id, retry, .. + } => { + if let Some(short_channel_id) = short_channel_id { + self.scorer.lock().payment_path_failed(path, *short_channel_id); + } + let mut payment_cache = self.payment_cache.lock().unwrap(); let entry = loop { let entry = payment_cache.entry(*payment_hash); @@ -354,11 +382,13 @@ mod tests { use lightning::ln::PaymentPreimage; use lightning::ln::features::{ChannelFeatures, NodeFeatures}; use lightning::ln::msgs::{ErrorAction, LightningError}; - use lightning::routing::router::{Route, RouteHop}; + use lightning::routing::network_graph::NodeId; + use lightning::routing::router::{Payee, Route, RouteHop}; use lightning::util::test_utils::TestLogger; use lightning::util::errors::APIError; use lightning::util::events::Event; use secp256k1::{SecretKey, PublicKey, Secp256k1}; + use std::cell::RefCell; use std::time::{SystemTime, Duration}; fn invoice(payment_preimage: PaymentPreimage) -> Invoice { @@ -422,9 +452,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(0)); let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap()); assert_eq!(*payer.attempts.borrow(), 1); @@ -450,9 +481,10 @@ mod tests { .expect_value_msat(final_value_msat) .expect_value_msat(final_value_msat / 2); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap()); assert_eq!(*payer.attempts.borrow(), 1); @@ -490,9 +522,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_id = Some(PaymentId([1; 32])); let event = Event::PaymentPathFailed { @@ -534,9 +567,10 @@ mod tests { .expect_value_msat(final_value_msat / 2) .expect_value_msat(final_value_msat / 2); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap()); assert_eq!(*payer.attempts.borrow(), 1); @@ -583,9 +617,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -614,9 +649,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = expired_invoice(payment_preimage); @@ -651,9 +687,10 @@ mod tests { .fails_on_attempt(2) .expect_value_msat(final_value_msat); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap()); assert_eq!(*payer.attempts.borrow(), 1); @@ -680,9 +717,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(2)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -711,9 +749,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(0)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -751,9 +790,10 @@ mod tests { fn fails_paying_invoice_with_routing_errors() { let payer = TestPayer::new(); let router = FailingRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, |_: &_| {}, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, |_: &_| {}, RetryAttempts(0)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -768,9 +808,10 @@ mod tests { fn fails_paying_invoice_with_sending_errors() { let payer = TestPayer::new().fails_on_attempt(1); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, |_: &_| {}, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, |_: &_| {}, RetryAttempts(0)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -793,9 +834,10 @@ mod tests { let payer = TestPayer::new().expect_value_msat(final_value_msat); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(0)); let payment_id = Some(invoice_payer.pay_zero_value_invoice(&invoice, final_value_msat).unwrap()); @@ -815,9 +857,10 @@ mod tests { let payer = TestPayer::new(); let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new()); let logger = TestLogger::new(); let invoice_payer = - InvoicePayer::new(&payer, router, &logger, event_handler, RetryAttempts(0)); + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(0)); let payment_preimage = PaymentPreimage([1; 32]); let invoice = invoice(payment_preimage); @@ -830,6 +873,40 @@ mod tests { } } + #[test] + fn scores_failed_channel() { + let event_handled = core::cell::RefCell::new(false); + let event_handler = |_: &_| { *event_handled.borrow_mut() = true; }; + + let payment_preimage = PaymentPreimage([1; 32]); + let invoice = invoice(payment_preimage); + let payment_hash = PaymentHash(invoice.payment_hash().clone().into_inner()); + let final_value_msat = invoice.amount_milli_satoshis().unwrap(); + let path = TestRouter::path_for_value(final_value_msat); + let short_channel_id = Some(path[0].short_channel_id); + + // Expect that scorer is given short_channel_id upon handling the event. + let payer = TestPayer::new(); + let router = TestRouter {}; + let scorer = RefCell::new(TestScorer::new().expect_channel_failure(short_channel_id.unwrap())); + let logger = TestLogger::new(); + let invoice_payer = + InvoicePayer::new(&payer, router, &scorer, &logger, event_handler, RetryAttempts(2)); + + let payment_id = Some(invoice_payer.pay_invoice(&invoice).unwrap()); + let event = Event::PaymentPathFailed { + payment_id, + payment_hash, + network_update: None, + rejected_by_dest: false, + all_paths_failed: false, + path, + short_channel_id, + retry: Some(TestRouter::retry_for_invoice(&invoice)), + }; + invoice_payer.handle_event(&event); + } + struct TestRouter; impl TestRouter { @@ -873,12 +950,13 @@ mod tests { } } - impl Router for TestRouter { + impl Router for TestRouter { fn find_route( &self, _payer: &PublicKey, params: &RouteParameters, _first_hops: Option<&[&ChannelDetails]>, + _scorer: &S, ) -> Result { Ok(Route { payee: Some(params.payee.clone()), ..Self::route_for_value(params.final_value_msat) @@ -888,17 +966,59 @@ mod tests { struct FailingRouter; - impl Router for FailingRouter { + impl Router for FailingRouter { fn find_route( &self, _payer: &PublicKey, _params: &RouteParameters, _first_hops: Option<&[&ChannelDetails]>, + _scorer: &S, ) -> Result { Err(LightningError { err: String::new(), action: ErrorAction::IgnoreError }) } } + struct TestScorer { + expectations: std::collections::VecDeque, + } + + impl TestScorer { + fn new() -> Self { + Self { + expectations: std::collections::VecDeque::new(), + } + } + + fn expect_channel_failure(mut self, short_channel_id: u64) -> Self { + self.expectations.push_back(short_channel_id); + self + } + } + + impl routing::Score for TestScorer { + fn channel_penalty_msat( + &self, _short_channel_id: u64, _source: &NodeId, _target: &NodeId + ) -> u64 { 0 } + + fn payment_path_failed(&mut self, _path: &Vec, short_channel_id: u64) { + if let Some(expected_short_channel_id) = self.expectations.pop_front() { + assert_eq!(short_channel_id, expected_short_channel_id); + } + } + } + + impl Drop for TestScorer { + fn drop(&mut self) { + if std::thread::panicking() { + return; + } + + if !self.expectations.is_empty() { + panic!("Unsatisfied channel failure expectations: {:?}", self.expectations); + } + } + } + struct TestPayer { expectations: core::cell::RefCell>, attempts: core::cell::RefCell, diff --git a/lightning-invoice/src/utils.rs b/lightning-invoice/src/utils.rs index ef885f20..e4714116 100644 --- a/lightning-invoice/src/utils.rs +++ b/lightning-invoice/src/utils.rs @@ -11,9 +11,9 @@ use lightning::chain::keysinterface::{Sign, KeysInterface}; use lightning::ln::{PaymentHash, PaymentSecret}; use lightning::ln::channelmanager::{ChannelDetails, ChannelManager, PaymentId, PaymentSendFailure, MIN_FINAL_CLTV_EXPIRY}; use lightning::ln::msgs::LightningError; +use lightning::routing; use lightning::routing::network_graph::{NetworkGraph, RoutingFees}; use lightning::routing::router::{Route, RouteHint, RouteHintHop, RouteParameters, find_route}; -use lightning::routing::scorer::Scorer; use lightning::util::logger::Logger; use secp256k1::key::PublicKey; use std::convert::TryInto; @@ -109,13 +109,13 @@ impl DefaultRouter where G: Deref, L:: } } -impl Router for DefaultRouter +impl Router for DefaultRouter where G: Deref, L::Target: Logger { fn find_route( &self, payer: &PublicKey, params: &RouteParameters, first_hops: Option<&[&ChannelDetails]>, + scorer: &S ) -> Result { - let scorer = Scorer::default(); - find_route(payer, params, &*self.network_graph, first_hops, &*self.logger, &scorer) + find_route(payer, params, &*self.network_graph, first_hops, &*self.logger, scorer) } } diff --git a/lightning/src/routing/mod.rs b/lightning/src/routing/mod.rs index 51ffd91b..d6c01646 100644 --- a/lightning/src/routing/mod.rs +++ b/lightning/src/routing/mod.rs @@ -14,6 +14,12 @@ pub mod router; pub mod scorer; use routing::network_graph::NodeId; +use routing::router::RouteHop; + +use prelude::*; +use core::cell::{RefCell, RefMut}; +use core::ops::DerefMut; +use sync::{Mutex, MutexGuard}; /// An interface used to score payment channels for path finding. /// @@ -22,4 +28,49 @@ pub trait Score { /// Returns the fee in msats willing to be paid to avoid routing through the given channel /// in the direction from `source` to `target`. fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId) -> u64; + + /// Handles updating channel penalties after failing to route through a channel. + fn payment_path_failed(&mut self, path: &Vec, short_channel_id: u64); +} + +/// A scorer that is accessed under a lock. +/// +/// Needed so that calls to [`Score::channel_penalty_msat`] in [`find_route`] can be made while +/// having shared ownership of a scorer but without requiring internal locking in [`Score`] +/// implementations. Internal locking would be detrimental to route finding performance and could +/// result in [`Score::channel_penalty_msat`] returning a different value for the same channel. +/// +/// [`find_route`]: crate::routing::router::find_route +pub trait LockableScore<'a> { + /// The locked [`Score`] type. + type Locked: 'a + Score; + + /// Returns the locked scorer. + fn lock(&'a self) -> Self::Locked; +} + +impl<'a, T: 'a + Score> LockableScore<'a> for Mutex { + type Locked = MutexGuard<'a, T>; + + fn lock(&'a self) -> MutexGuard<'a, T> { + Mutex::lock(self).unwrap() + } +} + +impl<'a, T: 'a + Score> LockableScore<'a> for RefCell { + type Locked = RefMut<'a, T>; + + fn lock(&'a self) -> RefMut<'a, T> { + self.borrow_mut() + } +} + +impl> Score for T { + fn channel_penalty_msat(&self, short_channel_id: u64, source: &NodeId, target: &NodeId) -> u64 { + self.deref().channel_penalty_msat(short_channel_id, source, target) + } + + fn payment_path_failed(&mut self, path: &Vec, short_channel_id: u64) { + self.deref_mut().payment_path_failed(path, short_channel_id) + } } diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs index 545ff9f2..226dbe04 100644 --- a/lightning/src/routing/router.rs +++ b/lightning/src/routing/router.rs @@ -4537,6 +4537,8 @@ mod tests { fn channel_penalty_msat(&self, short_channel_id: u64, _source: &NodeId, _target: &NodeId) -> u64 { if short_channel_id == self.short_channel_id { u64::max_value() } else { 0 } } + + fn payment_path_failed(&mut self, _path: &Vec, _short_channel_id: u64) {} } struct BadNodeScorer { @@ -4547,6 +4549,8 @@ mod tests { fn channel_penalty_msat(&self, _short_channel_id: u64, _source: &NodeId, target: &NodeId) -> u64 { if *target == self.node_id { u64::max_value() } else { 0 } } + + fn payment_path_failed(&mut self, _path: &Vec, _short_channel_id: u64) {} } #[test] diff --git a/lightning/src/routing/scorer.rs b/lightning/src/routing/scorer.rs index e3f5c867..01481f16 100644 --- a/lightning/src/routing/scorer.rs +++ b/lightning/src/routing/scorer.rs @@ -45,6 +45,9 @@ use routing; use routing::network_graph::NodeId; +use routing::router::RouteHop; + +use prelude::*; /// [`routing::Score`] implementation that provides reasonable default behavior. /// @@ -78,4 +81,6 @@ impl routing::Score for Scorer { ) -> u64 { self.base_penalty_msat } + + fn payment_path_failed(&mut self, _path: &Vec, _short_channel_id: u64) {} }