_ Git - rust-lightning/blob - lightning/src/ln/outbound_payment.rs

   1 // This file is Copyright its original authors, visible in version control
   2 // history.
   3 //
   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
   8 // licenses.
   9
  10 //! Utilities to send payments and manage outbound payment information.
  11
  12 use bitcoin::hashes::Hash;
  13 use bitcoin::hashes::sha256::Hash as Sha256;
  14 use bitcoin::secp256k1::{self, Secp256k1, SecretKey};
  15
  16 use crate::chain::keysinterface::{EntropySource, NodeSigner, Recipient};
  17 use crate::events;
  18 use crate::ln::{PaymentHash, PaymentPreimage, PaymentSecret};
  19 use crate::ln::channelmanager::{ChannelDetails, HTLCSource, IDEMPOTENCY_TIMEOUT_TICKS, PaymentId};
  20 use crate::ln::onion_utils::HTLCFailReason;
  21 use crate::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteHop, RouteParameters, RoutePath, Router};
  22 use crate::util::errors::APIError;
  23 use crate::util::logger::Logger;
  24 use crate::util::time::Time;
  25 #[cfg(all(not(feature = "no-std"), test))]
  26 use crate::util::time::tests::SinceEpoch;
  27 use crate::util::ser::ReadableArgs;
  28
  29 use core::cmp;
  30 use core::fmt::{self, Display, Formatter};
  31 use core::ops::Deref;
  32
  33 use crate::prelude::*;
  34 use crate::sync::Mutex;
  35
  36 /// Stores the session_priv for each part of a payment that is still pending. For versions 0.0.102
  37 /// and later, also stores information for retrying the payment.
  38 pub(crate) enum PendingOutboundPayment {
  39         Legacy {
  40                 session_privs: HashSet<[u8; 32]>,
  41         },
  42         Retryable {
  43                 retry_strategy: Option<Retry>,
  44                 attempts: PaymentAttempts,
  45                 payment_params: Option<PaymentParameters>,
  46                 session_privs: HashSet<[u8; 32]>,
  47                 payment_hash: PaymentHash,
  48                 payment_secret: Option<PaymentSecret>,
  49                 keysend_preimage: Option<PaymentPreimage>,
  50                 pending_amt_msat: u64,
  51                 /// Used to track the fee paid. Only present if the payment was serialized on 0.0.103+.
  52                 pending_fee_msat: Option<u64>,
  53                 /// The total payment amount across all paths, used to verify that a retry is not overpaying.
  54                 total_msat: u64,
  55                 /// Our best known block height at the time this payment was initiated.
  56                 starting_block_height: u32,
  57         },
  58         /// When a pending payment is fulfilled, we continue tracking it until all pending HTLCs have
  59         /// been resolved. This ensures we don't look up pending payments in ChannelMonitors on restart
  60         /// and add a pending payment that was already fulfilled.
  61         Fulfilled {
  62                 session_privs: HashSet<[u8; 32]>,
  63                 payment_hash: Option<PaymentHash>,
  64                 timer_ticks_without_htlcs: u8,
  65         },
  66         /// When we've decided to give up retrying a payment, we mark it as abandoned so we can eventually
  67         /// generate a `PaymentFailed` event when all HTLCs have irrevocably failed.
  68         Abandoned {
  69                 session_privs: HashSet<[u8; 32]>,
  70                 payment_hash: PaymentHash,
  71         },
  72 }
  73
  74 impl PendingOutboundPayment {
  75         fn increment_attempts(&mut self) {
  76                 if let PendingOutboundPayment::Retryable { attempts, .. } = self {
  77                         attempts.count += 1;
  78                 }
  79         }
  80         fn is_auto_retryable_now(&self) -> bool {
  81                 match self {
  82                         PendingOutboundPayment::Retryable {
  83                                 retry_strategy: Some(strategy), attempts, payment_params: Some(_), ..
  84                         } => {
  85                                 strategy.is_retryable_now(&attempts)
  86                         },
  87                         _ => false,
  88                 }
  89         }
  90         fn is_retryable_now(&self) -> bool {
  91                 match self {
  92                         PendingOutboundPayment::Retryable { retry_strategy: None, .. } => {
  93                                 // We're handling retries manually, we can always retry.
  94                                 true
  95                         },
  96                         PendingOutboundPayment::Retryable { retry_strategy: Some(strategy), attempts, .. } => {
  97                                 strategy.is_retryable_now(&attempts)
  98                         },
  99                         _ => false,
 100                 }
 101         }
 102         pub fn insert_previously_failed_scid(&mut self, scid: u64) {
 103                 if let PendingOutboundPayment::Retryable { payment_params: Some(params), .. } = self {
 104                         params.previously_failed_channels.push(scid);
 105                 }
 106         }
 107         pub(super) fn is_fulfilled(&self) -> bool {
 108                 match self {
 109                         PendingOutboundPayment::Fulfilled { .. } => true,
 110                         _ => false,
 111                 }
 112         }
 113         pub(super) fn abandoned(&self) -> bool {
 114                 match self {
 115                         PendingOutboundPayment::Abandoned { .. } => true,
 116                         _ => false,
 117                 }
 118         }
 119         fn get_pending_fee_msat(&self) -> Option<u64> {
 120                 match self {
 121                         PendingOutboundPayment::Retryable { pending_fee_msat, .. } => pending_fee_msat.clone(),
 122                         _ => None,
 123                 }
 124         }
 125
 126         fn payment_hash(&self) -> Option<PaymentHash> {
 127                 match self {
 128                         PendingOutboundPayment::Legacy { .. } => None,
 129                         PendingOutboundPayment::Retryable { payment_hash, .. } => Some(*payment_hash),
 130                         PendingOutboundPayment::Fulfilled { payment_hash, .. } => *payment_hash,
 131                         PendingOutboundPayment::Abandoned { payment_hash, .. } => Some(*payment_hash),
 132                 }
 133         }
 134
 135         fn mark_fulfilled(&mut self) {
 136                 let mut session_privs = HashSet::new();
 137                 core::mem::swap(&mut session_privs, match self {
 138                         PendingOutboundPayment::Legacy { session_privs } |
 139                                 PendingOutboundPayment::Retryable { session_privs, .. } |
 140                                 PendingOutboundPayment::Fulfilled { session_privs, .. } |
 141                                 PendingOutboundPayment::Abandoned { session_privs, .. }
 142                         => session_privs,
 143                 });
 144                 let payment_hash = self.payment_hash();
 145                 *self = PendingOutboundPayment::Fulfilled { session_privs, payment_hash, timer_ticks_without_htlcs: 0 };
 146         }
 147
 148         fn mark_abandoned(&mut self) -> Result<(), ()> {
 149                 let mut session_privs = HashSet::new();
 150                 let our_payment_hash;
 151                 core::mem::swap(&mut session_privs, match self {
 152                         PendingOutboundPayment::Legacy { .. } |
 153                         PendingOutboundPayment::Fulfilled { .. } =>
 154                                 return Err(()),
 155                         PendingOutboundPayment::Retryable { session_privs, payment_hash, .. } |
 156                         PendingOutboundPayment::Abandoned { session_privs, payment_hash, .. } => {
 157                                 our_payment_hash = *payment_hash;
 158                                 session_privs
 159                         },
 160                 });
 161                 *self = PendingOutboundPayment::Abandoned { session_privs, payment_hash: our_payment_hash };
 162                 Ok(())
 163         }
 164
 165         /// panics if path is None and !self.is_fulfilled
 166         fn remove(&mut self, session_priv: &[u8; 32], path: Option<&Vec<RouteHop>>) -> bool {
 167                 let remove_res = match self {
 168                         PendingOutboundPayment::Legacy { session_privs } |
 169                                 PendingOutboundPayment::Retryable { session_privs, .. } |
 170                                 PendingOutboundPayment::Fulfilled { session_privs, .. } |
 171                                 PendingOutboundPayment::Abandoned { session_privs, .. } => {
 172                                         session_privs.remove(session_priv)
 173                                 }
 174                 };
 175                 if remove_res {
 176                         if let PendingOutboundPayment::Retryable { ref mut pending_amt_msat, ref mut pending_fee_msat, .. } = self {
 177                                 let path = path.expect("Fulfilling a payment should always come with a path");
 178                                 let path_last_hop = path.last().expect("Outbound payments must have had a valid path");
 179                                 *pending_amt_msat -= path_last_hop.fee_msat;
 180                                 if let Some(fee_msat) = pending_fee_msat.as_mut() {
 181                                         *fee_msat -= path.get_path_fees();
 182                                 }
 183                         }
 184                 }
 185                 remove_res
 186         }
 187
 188         pub(super) fn insert(&mut self, session_priv: [u8; 32], path: &Vec<RouteHop>) -> bool {
 189                 let insert_res = match self {
 190                         PendingOutboundPayment::Legacy { session_privs } |
 191                                 PendingOutboundPayment::Retryable { session_privs, .. } => {
 192                                         session_privs.insert(session_priv)
 193                                 }
 194                         PendingOutboundPayment::Fulfilled { .. } => false,
 195                         PendingOutboundPayment::Abandoned { .. } => false,
 196                 };
 197                 if insert_res {
 198                         if let PendingOutboundPayment::Retryable { ref mut pending_amt_msat, ref mut pending_fee_msat, .. } = self {
 199                                 let path_last_hop = path.last().expect("Outbound payments must have had a valid path");
 200                                 *pending_amt_msat += path_last_hop.fee_msat;
 201                                 if let Some(fee_msat) = pending_fee_msat.as_mut() {
 202                                         *fee_msat += path.get_path_fees();
 203                                 }
 204                         }
 205                 }
 206                 insert_res
 207         }
 208
 209         pub(super) fn remaining_parts(&self) -> usize {
 210                 match self {
 211                         PendingOutboundPayment::Legacy { session_privs } |
 212                                 PendingOutboundPayment::Retryable { session_privs, .. } |
 213                                 PendingOutboundPayment::Fulfilled { session_privs, .. } |
 214                                 PendingOutboundPayment::Abandoned { session_privs, .. } => {
 215                                         session_privs.len()
 216                                 }
 217                 }
 218         }
 219 }
 220
 221 /// Strategies available to retry payment path failures.
 222 #[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
 223 pub enum Retry {
 224         /// Max number of attempts to retry payment.
 225         ///
 226         /// Each attempt may be multiple HTLCs along multiple paths if the router decides to split up a
 227         /// retry, and may retry multiple failed HTLCs at once if they failed around the same time and
 228         /// were retried along a route from a single call to [`Router::find_route_with_id`].
 229         Attempts(usize),
 230         #[cfg(not(feature = "no-std"))]
 231         /// Time elapsed before abandoning retries for a payment. At least one attempt at payment is made;
 232         /// see [`PaymentParameters::expiry_time`] to avoid any attempt at payment after a specific time.
 233         ///
 234         /// [`PaymentParameters::expiry_time`]: crate::routing::router::PaymentParameters::expiry_time
 235         Timeout(core::time::Duration),
 236 }
 237
 238 impl Retry {
 239         pub(crate) fn is_retryable_now(&self, attempts: &PaymentAttempts) -> bool {
 240                 match (self, attempts) {
 241                         (Retry::Attempts(max_retry_count), PaymentAttempts { count, .. }) => {
 242                                 max_retry_count > count
 243                         },
 244                         #[cfg(all(not(feature = "no-std"), not(test)))]
 245                         (Retry::Timeout(max_duration), PaymentAttempts { first_attempted_at, .. }) =>
 246                                 *max_duration >= std::time::Instant::now().duration_since(*first_attempted_at),
 247                         #[cfg(all(not(feature = "no-std"), test))]
 248                         (Retry::Timeout(max_duration), PaymentAttempts { first_attempted_at, .. }) =>
 249                                 *max_duration >= SinceEpoch::now().duration_since(*first_attempted_at),
 250                 }
 251         }
 252 }
 253
 254 #[cfg(feature = "std")]
 255 pub(super) fn has_expired(route_params: &RouteParameters) -> bool {
 256         if let Some(expiry_time) = route_params.payment_params.expiry_time {
 257                 if let Ok(elapsed) = std::time::SystemTime::UNIX_EPOCH.elapsed() {
 258                         return elapsed > core::time::Duration::from_secs(expiry_time)
 259                 }
 260         }
 261         false
 262 }
 263
 264 pub(crate) type PaymentAttempts = PaymentAttemptsUsingTime<ConfiguredTime>;
 265
 266 /// Storing minimal payment attempts information required for determining if a outbound payment can
 267 /// be retried.
 268 pub(crate) struct PaymentAttemptsUsingTime<T: Time> {
 269         /// This count will be incremented only after the result of the attempt is known. When it's 0,
 270         /// it means the result of the first attempt is not known yet.
 271         pub(crate) count: usize,
 272         /// This field is only used when retry is `Retry::Timeout` which is only build with feature std
 273         #[cfg(not(feature = "no-std"))]
 274         first_attempted_at: T,
 275         #[cfg(feature = "no-std")]
 276         phantom: core::marker::PhantomData<T>,
 277
 278 }
 279
 280 #[cfg(not(any(feature = "no-std", test)))]
 281 type ConfiguredTime = std::time::Instant;
 282 #[cfg(feature = "no-std")]
 283 type ConfiguredTime = crate::util::time::Eternity;
 284 #[cfg(all(not(feature = "no-std"), test))]
 285 type ConfiguredTime = SinceEpoch;
 286
 287 impl<T: Time> PaymentAttemptsUsingTime<T> {
 288         pub(crate) fn new() -> Self {
 289                 PaymentAttemptsUsingTime {
 290                         count: 0,
 291                         #[cfg(not(feature = "no-std"))]
 292                         first_attempted_at: T::now(),
 293                         #[cfg(feature = "no-std")]
 294                         phantom: core::marker::PhantomData,
 295                 }
 296         }
 297 }
 298
 299 impl<T: Time> Display for PaymentAttemptsUsingTime<T> {
 300         fn fmt(&self, f: &mut Formatter) -> Result<(), fmt::Error> {
 301                 #[cfg(feature = "no-std")]
 302                 return write!(f, "attempts: {}", self.count);
 303                 #[cfg(not(feature = "no-std"))]
 304                 return write!(
 305                         f,
 306                         "attempts: {}, duration: {}s",
 307                         self.count,
 308                         T::now().duration_since(self.first_attempted_at).as_secs()
 309                 );
 310         }
 311 }
 312
 313 /// Indicates an immediate error on [`ChannelManager::send_payment_with_retry`]. Further errors
 314 /// may be surfaced later via [`Event::PaymentPathFailed`] and [`Event::PaymentFailed`].
 315 ///
 316 /// [`ChannelManager::send_payment_with_retry`]: crate::ln::channelmanager::ChannelManager::send_payment_with_retry
 317 /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
 318 /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 319 #[derive(Clone, Debug)]
 320 pub enum RetryableSendFailure {
 321         /// The provided [`PaymentParameters::expiry_time`] indicated that the payment has expired. Note
 322         /// that this error is *not* caused by [`Retry::Timeout`].
 323         ///
 324         /// [`PaymentParameters::expiry_time`]: crate::routing::router::PaymentParameters::expiry_time
 325         PaymentExpired,
 326         /// We were unable to find a route to the destination.
 327         RouteNotFound,
 328         /// Indicates that a payment for the provided [`PaymentId`] is already in-flight and has not
 329         /// yet completed (i.e. generated an [`Event::PaymentSent`] or [`Event::PaymentFailed`]).
 330         ///
 331         /// [`PaymentId`]: crate::ln::channelmanager::PaymentId
 332         /// [`Event::PaymentSent`]: crate::events::Event::PaymentSent
 333         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 334         DuplicatePayment,
 335 }
 336
 337 /// If a payment fails to send with [`ChannelManager::send_payment`], it can be in one of several
 338 /// states. This enum is returned as the Err() type describing which state the payment is in, see
 339 /// the description of individual enum states for more.
 340 ///
 341 /// [`ChannelManager::send_payment`]: crate::ln::channelmanager::ChannelManager::send_payment
 342 #[derive(Clone, Debug)]
 343 pub enum PaymentSendFailure {
 344         /// A parameter which was passed to send_payment was invalid, preventing us from attempting to
 345         /// send the payment at all.
 346         ///
 347         /// You can freely resend the payment in full (with the parameter error fixed).
 348         ///
 349         /// Because the payment failed outright, no payment tracking is done and no
 350         /// [`Event::PaymentPathFailed`] or [`Event::PaymentFailed`] events will be generated.
 351         ///
 352         /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
 353         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 354         ParameterError(APIError),
 355         /// A parameter in a single path which was passed to send_payment was invalid, preventing us
 356         /// from attempting to send the payment at all.
 357         ///
 358         /// You can freely resend the payment in full (with the parameter error fixed).
 359         ///
 360         /// Because the payment failed outright, no payment tracking is done and no
 361         /// [`Event::PaymentPathFailed`] or [`Event::PaymentFailed`] events will be generated.
 362         ///
 363         /// The results here are ordered the same as the paths in the route object which was passed to
 364         /// send_payment.
 365         ///
 366         /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
 367         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 368         PathParameterError(Vec<Result<(), APIError>>),
 369         /// All paths which were attempted failed to send, with no channel state change taking place.
 370         /// You can freely resend the payment in full (though you probably want to do so over different
 371         /// paths than the ones selected).
 372         ///
 373         /// Because the payment failed outright, no payment tracking is done and no
 374         /// [`Event::PaymentPathFailed`] or [`Event::PaymentFailed`] events will be generated.
 375         ///
 376         /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
 377         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 378         AllFailedResendSafe(Vec<APIError>),
 379         /// Indicates that a payment for the provided [`PaymentId`] is already in-flight and has not
 380         /// yet completed (i.e. generated an [`Event::PaymentSent`] or [`Event::PaymentFailed`]).
 381         ///
 382         /// [`PaymentId`]: crate::ln::channelmanager::PaymentId
 383         /// [`Event::PaymentSent`]: crate::events::Event::PaymentSent
 384         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 385         DuplicatePayment,
 386         /// Some paths that were attempted failed to send, though some paths may have succeeded. At least
 387         /// some paths have irrevocably committed to the HTLC.
 388         ///
 389         /// The results here are ordered the same as the paths in the route object that was passed to
 390         /// send_payment.
 391         ///
 392         /// Any entries that contain `Err(APIError::MonitorUpdateInprogress)` will send once a
 393         /// [`MonitorEvent::Completed`] is provided for the next-hop channel with the latest update_id.
 394         ///
 395         /// [`MonitorEvent::Completed`]: crate::chain::channelmonitor::MonitorEvent::Completed
 396         PartialFailure {
 397                 /// The errors themselves, in the same order as the paths from the route.
 398                 results: Vec<Result<(), APIError>>,
 399                 /// If some paths failed without irrevocably committing to the new HTLC(s), this will
 400                 /// contain a [`RouteParameters`] object for the failing paths.
 401                 failed_paths_retry: Option<RouteParameters>,
 402                 /// The payment id for the payment, which is now at least partially pending.
 403                 payment_id: PaymentId,
 404         },
 405 }
 406
 407 pub(super) struct OutboundPayments {
 408         pub(super) pending_outbound_payments: Mutex<HashMap<PaymentId, PendingOutboundPayment>>,
 409         pub(super) retry_lock: Mutex<()>,
 410 }
 411
 412 impl OutboundPayments {
 413         pub(super) fn new() -> Self {
 414                 Self {
 415                         pending_outbound_payments: Mutex::new(HashMap::new()),
 416                         retry_lock: Mutex::new(()),
 417                 }
 418         }
 419
 420         pub(super) fn send_payment<R: Deref, ES: Deref, NS: Deref, IH, SP, L: Deref>(
 421                 &self, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>, payment_id: PaymentId,
 422                 retry_strategy: Retry, route_params: RouteParameters, router: &R,
 423                 first_hops: Vec<ChannelDetails>, compute_inflight_htlcs: IH, entropy_source: &ES,
 424                 node_signer: &NS, best_block_height: u32, logger: &L,
 425                 pending_events: &Mutex<Vec<events::Event>>, send_payment_along_path: SP,
 426         ) -> Result<(), RetryableSendFailure>
 427         where
 428                 R::Target: Router,
 429                 ES::Target: EntropySource,
 430                 NS::Target: NodeSigner,
 431                 L::Target: Logger,
 432                 IH: Fn() -> InFlightHtlcs,
 433                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 434                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>,
 435         {
 436                 self.send_payment_internal(payment_id, payment_hash, payment_secret, None, retry_strategy,
 437                         route_params, router, first_hops, &compute_inflight_htlcs, entropy_source, node_signer,
 438                         best_block_height, logger, pending_events, &send_payment_along_path)
 439         }
 440
 441         pub(super) fn send_payment_with_route<ES: Deref, NS: Deref, F>(
 442                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>,
 443                 payment_id: PaymentId, entropy_source: &ES, node_signer: &NS, best_block_height: u32,
 444                 send_payment_along_path: F
 445         ) -> Result<(), PaymentSendFailure>
 446         where
 447                 ES::Target: EntropySource,
 448                 NS::Target: NodeSigner,
 449                 F: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 450                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 451         {
 452                 let onion_session_privs = self.add_new_pending_payment(payment_hash, *payment_secret, payment_id, None, route, None, None, entropy_source, best_block_height)?;
 453                 self.pay_route_internal(route, payment_hash, payment_secret, None, payment_id, None,
 454                         onion_session_privs, node_signer, best_block_height, &send_payment_along_path)
 455                         .map_err(|e| { self.remove_outbound_if_all_failed(payment_id, &e); e })
 456         }
 457
 458         pub(super) fn send_spontaneous_payment<R: Deref, ES: Deref, NS: Deref, IH, SP, L: Deref>(
 459                 &self, payment_preimage: Option<PaymentPreimage>, payment_id: PaymentId,
 460                 retry_strategy: Retry, route_params: RouteParameters, router: &R,
 461                 first_hops: Vec<ChannelDetails>, inflight_htlcs: IH, entropy_source: &ES,
 462                 node_signer: &NS, best_block_height: u32, logger: &L,
 463                 pending_events: &Mutex<Vec<events::Event>>, send_payment_along_path: SP
 464         ) -> Result<PaymentHash, RetryableSendFailure>
 465         where
 466                 R::Target: Router,
 467                 ES::Target: EntropySource,
 468                 NS::Target: NodeSigner,
 469                 L::Target: Logger,
 470                 IH: Fn() -> InFlightHtlcs,
 471                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 472                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>,
 473         {
 474                 let preimage = payment_preimage
 475                         .unwrap_or_else(|| PaymentPreimage(entropy_source.get_secure_random_bytes()));
 476                 let payment_hash = PaymentHash(Sha256::hash(&preimage.0).into_inner());
 477                 self.send_payment_internal(payment_id, payment_hash, &None, Some(preimage), retry_strategy,
 478                         route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer,
 479                         best_block_height, logger, pending_events, send_payment_along_path)
 480                         .map(|()| payment_hash)
 481         }
 482
 483         pub(super) fn send_spontaneous_payment_with_route<ES: Deref, NS: Deref, F>(
 484                 &self, route: &Route, payment_preimage: Option<PaymentPreimage>, payment_id: PaymentId,
 485                 entropy_source: &ES, node_signer: &NS, best_block_height: u32, send_payment_along_path: F
 486         ) -> Result<PaymentHash, PaymentSendFailure>
 487         where
 488                 ES::Target: EntropySource,
 489                 NS::Target: NodeSigner,
 490                 F: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 491                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 492         {
 493                 let preimage = payment_preimage
 494                         .unwrap_or_else(|| PaymentPreimage(entropy_source.get_secure_random_bytes()));
 495                 let payment_hash = PaymentHash(Sha256::hash(&preimage.0).into_inner());
 496                 let onion_session_privs = self.add_new_pending_payment(payment_hash, None, payment_id, Some(preimage), &route, None, None, entropy_source, best_block_height)?;
 497
 498                 match self.pay_route_internal(route, payment_hash, &None, Some(preimage), payment_id, None, onion_session_privs, node_signer, best_block_height, &send_payment_along_path) {
 499                         Ok(()) => Ok(payment_hash),
 500                         Err(e) => {
 501                                 self.remove_outbound_if_all_failed(payment_id, &e);
 502                                 Err(e)
 503                         }
 504                 }
 505         }
 506
 507         pub(super) fn check_retry_payments<R: Deref, ES: Deref, NS: Deref, SP, IH, FH, L: Deref>(
 508                 &self, router: &R, first_hops: FH, inflight_htlcs: IH, entropy_source: &ES, node_signer: &NS,
 509                 best_block_height: u32, pending_events: &Mutex<Vec<events::Event>>, logger: &L,
 510                 send_payment_along_path: SP,
 511         )
 512         where
 513                 R::Target: Router,
 514                 ES::Target: EntropySource,
 515                 NS::Target: NodeSigner,
 516                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 517                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>,
 518                 IH: Fn() -> InFlightHtlcs,
 519                 FH: Fn() -> Vec<ChannelDetails>,
 520                 L::Target: Logger,
 521         {
 522                 let _single_thread = self.retry_lock.lock().unwrap();
 523                 loop {
 524                         let mut outbounds = self.pending_outbound_payments.lock().unwrap();
 525                         let mut retry_id_route_params = None;
 526                         for (pmt_id, pmt) in outbounds.iter_mut() {
 527                                 if pmt.is_auto_retryable_now() {
 528                                         if let PendingOutboundPayment::Retryable { pending_amt_msat, total_msat, payment_params: Some(params), payment_hash, .. } = pmt {
 529                                                 if pending_amt_msat < total_msat {
 530                                                         retry_id_route_params = Some((*payment_hash, *pmt_id, RouteParameters {
 531                                                                 final_value_msat: *total_msat - *pending_amt_msat,
 532                                                                 payment_params: params.clone(),
 533                                                         }));
 534                                                         break
 535                                                 }
 536                                         } else { debug_assert!(false); }
 537                                 }
 538                         }
 539                         core::mem::drop(outbounds);
 540                         if let Some((payment_hash, payment_id, route_params)) = retry_id_route_params {
 541                                 self.retry_payment_internal(payment_hash, payment_id, route_params, router, first_hops(), &inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, &send_payment_along_path)
 542                         } else { break }
 543                 }
 544
 545                 let mut outbounds = self.pending_outbound_payments.lock().unwrap();
 546                 outbounds.retain(|pmt_id, pmt| {
 547                         let mut retain = true;
 548                         if !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 {
 549                                 if pmt.mark_abandoned().is_ok() {
 550                                         pending_events.lock().unwrap().push(events::Event::PaymentFailed {
 551                                                 payment_id: *pmt_id,
 552                                                 payment_hash: pmt.payment_hash().expect("PendingOutboundPayments::Retryable always has a payment hash set"),
 553                                         });
 554                                         retain = false;
 555                                 }
 556                         }
 557                         retain
 558                 });
 559         }
 560
 561         pub(super) fn needs_abandon(&self) -> bool {
 562                 let outbounds = self.pending_outbound_payments.lock().unwrap();
 563                 outbounds.iter().any(|(_, pmt)|
 564                         !pmt.is_auto_retryable_now() && pmt.remaining_parts() == 0 && !pmt.is_fulfilled())
 565         }
 566
 567         /// Errors immediately on [`RetryableSendFailure`] error conditions. Otherwise, further errors may
 568         /// be surfaced asynchronously via [`Event::PaymentPathFailed`] and [`Event::PaymentFailed`].
 569         ///
 570         /// [`Event::PaymentPathFailed`]: crate::events::Event::PaymentPathFailed
 571         /// [`Event::PaymentFailed`]: crate::events::Event::PaymentFailed
 572         fn send_payment_internal<R: Deref, NS: Deref, ES: Deref, IH, SP, L: Deref>(
 573                 &self, payment_id: PaymentId, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>,
 574                 keysend_preimage: Option<PaymentPreimage>, retry_strategy: Retry, route_params: RouteParameters,
 575                 router: &R, first_hops: Vec<ChannelDetails>, inflight_htlcs: IH, entropy_source: &ES,
 576                 node_signer: &NS, best_block_height: u32, logger: &L,
 577                 pending_events: &Mutex<Vec<events::Event>>, send_payment_along_path: SP,
 578         ) -> Result<(), RetryableSendFailure>
 579         where
 580                 R::Target: Router,
 581                 ES::Target: EntropySource,
 582                 NS::Target: NodeSigner,
 583                 L::Target: Logger,
 584                 IH: Fn() -> InFlightHtlcs,
 585                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 586                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 587         {
 588                 #[cfg(feature = "std")] {
 589                         if has_expired(&route_params) {
 590                                 return Err(RetryableSendFailure::PaymentExpired)
 591                         }
 592                 }
 593
 594                 let route = router.find_route_with_id(
 595                         &node_signer.get_node_id(Recipient::Node).unwrap(), &route_params,
 596                         Some(&first_hops.iter().collect::<Vec<_>>()), &inflight_htlcs(),
 597                         payment_hash, payment_id,
 598                 ).map_err(|_| RetryableSendFailure::RouteNotFound)?;
 599
 600                 let onion_session_privs = self.add_new_pending_payment(payment_hash, *payment_secret,
 601                         payment_id, keysend_preimage, &route, Some(retry_strategy),
 602                         Some(route_params.payment_params.clone()), entropy_source, best_block_height)
 603                         .map_err(|_| RetryableSendFailure::DuplicatePayment)?;
 604
 605                 let res = self.pay_route_internal(&route, payment_hash, payment_secret, None, payment_id, None,
 606                         onion_session_privs, node_signer, best_block_height, &send_payment_along_path);
 607                 log_info!(logger, "Result sending payment with id {}: {:?}", log_bytes!(payment_id.0), res);
 608                 if let Err(e) = res {
 609                         self.handle_pay_route_err(e, payment_id, payment_hash, route, route_params, router, first_hops, &inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, &send_payment_along_path);
 610                 }
 611                 Ok(())
 612         }
 613
 614         fn retry_payment_internal<R: Deref, NS: Deref, ES: Deref, IH, SP, L: Deref>(
 615                 &self, payment_hash: PaymentHash, payment_id: PaymentId, route_params: RouteParameters,
 616                 router: &R, first_hops: Vec<ChannelDetails>, inflight_htlcs: &IH, entropy_source: &ES,
 617                 node_signer: &NS, best_block_height: u32, logger: &L,
 618                 pending_events: &Mutex<Vec<events::Event>>, send_payment_along_path: &SP,
 619         )
 620         where
 621                 R::Target: Router,
 622                 ES::Target: EntropySource,
 623                 NS::Target: NodeSigner,
 624                 L::Target: Logger,
 625                 IH: Fn() -> InFlightHtlcs,
 626                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 627                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 628         {
 629                 #[cfg(feature = "std")] {
 630                         if has_expired(&route_params) {
 631                                 log_error!(logger, "Payment params expired on retry, abandoning payment {}", log_bytes!(payment_id.0));
 632                                 self.abandon_payment(payment_id, pending_events);
 633                                 return
 634                         }
 635                 }
 636
 637                 let route = match router.find_route_with_id(
 638                         &node_signer.get_node_id(Recipient::Node).unwrap(), &route_params,
 639                         Some(&first_hops.iter().collect::<Vec<_>>()), &inflight_htlcs(),
 640                         payment_hash, payment_id,
 641                 ) {
 642                         Ok(route) => route,
 643                         Err(e) => {
 644                                 log_error!(logger, "Failed to find a route on retry, abandoning payment {}: {:#?}", log_bytes!(payment_id.0), e);
 645                                 self.abandon_payment(payment_id, pending_events);
 646                                 return
 647                         }
 648                 };
 649                 for path in route.paths.iter() {
 650                         if path.len() == 0 {
 651                                 log_error!(logger, "length-0 path in route");
 652                                 self.abandon_payment(payment_id, pending_events);
 653                                 return
 654                         }
 655                 }
 656
 657                 const RETRY_OVERFLOW_PERCENTAGE: u64 = 10;
 658                 let mut onion_session_privs = Vec::with_capacity(route.paths.len());
 659                 for _ in 0..route.paths.len() {
 660                         onion_session_privs.push(entropy_source.get_secure_random_bytes());
 661                 }
 662
 663                 macro_rules! abandon_with_entry {
 664                         ($payment: expr) => {
 665                                 if $payment.get_mut().mark_abandoned().is_ok() && $payment.get().remaining_parts() == 0 {
 666                                         pending_events.lock().unwrap().push(events::Event::PaymentFailed {
 667                                                 payment_id,
 668                                                 payment_hash,
 669                                         });
 670                                         $payment.remove();
 671                                 }
 672                         }
 673                 }
 674                 let (total_msat, payment_secret, keysend_preimage) = {
 675                         let mut outbounds = self.pending_outbound_payments.lock().unwrap();
 676                         match outbounds.entry(payment_id) {
 677                                 hash_map::Entry::Occupied(mut payment) => {
 678                                         let res = match payment.get() {
 679                                                 PendingOutboundPayment::Retryable {
 680                                                         total_msat, keysend_preimage, payment_secret, pending_amt_msat, ..
 681                                                 } => {
 682                                                         let retry_amt_msat: u64 = route.paths.iter().map(|path| path.last().unwrap().fee_msat).sum();
 683                                                         if retry_amt_msat + *pending_amt_msat > *total_msat * (100 + RETRY_OVERFLOW_PERCENTAGE) / 100 {
 684                                                                 log_error!(logger, "retry_amt_msat of {} will put pending_amt_msat (currently: {}) more than 10% over total_payment_amt_msat of {}", retry_amt_msat, pending_amt_msat, total_msat);
 685                                                                 abandon_with_entry!(payment);
 686                                                                 return
 687                                                         }
 688                                                         (*total_msat, *payment_secret, *keysend_preimage)
 689                                                 },
 690                                                 PendingOutboundPayment::Legacy { .. } => {
 691                                                         log_error!(logger, "Unable to retry payments that were initially sent on LDK versions prior to 0.0.102");
 692                                                         return
 693                                                 },
 694                                                 PendingOutboundPayment::Fulfilled { .. } => {
 695                                                         log_error!(logger, "Payment already completed");
 696                                                         return
 697                                                 },
 698                                                 PendingOutboundPayment::Abandoned { .. } => {
 699                                                         log_error!(logger, "Payment already abandoned (with some HTLCs still pending)");
 700                                                         return
 701                                                 },
 702                                         };
 703                                         if !payment.get().is_retryable_now() {
 704                                                 log_error!(logger, "Retries exhausted for payment id {}", log_bytes!(payment_id.0));
 705                                                 abandon_with_entry!(payment);
 706                                                 return
 707                                         }
 708                                         payment.get_mut().increment_attempts();
 709                                         for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
 710                                                 assert!(payment.get_mut().insert(*session_priv_bytes, path));
 711                                         }
 712                                         res
 713                                 },
 714                                 hash_map::Entry::Vacant(_) => {
 715                                         log_error!(logger, "Payment with ID {} not found", log_bytes!(payment_id.0));
 716                                         return
 717                                 }
 718                         }
 719                 };
 720                 let res = self.pay_route_internal(&route, payment_hash, &payment_secret, keysend_preimage,
 721                         payment_id, Some(total_msat), onion_session_privs, node_signer, best_block_height,
 722                         &send_payment_along_path);
 723                 log_info!(logger, "Result retrying payment id {}: {:?}", log_bytes!(payment_id.0), res);
 724                 if let Err(e) = res {
 725                         self.handle_pay_route_err(e, payment_id, payment_hash, route, route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
 726                 }
 727         }
 728
 729         fn handle_pay_route_err<R: Deref, NS: Deref, ES: Deref, IH, SP, L: Deref>(
 730                 &self, err: PaymentSendFailure, payment_id: PaymentId, payment_hash: PaymentHash, route: Route,
 731                 mut route_params: RouteParameters, router: &R, first_hops: Vec<ChannelDetails>,
 732                 inflight_htlcs: &IH, entropy_source: &ES, node_signer: &NS, best_block_height: u32, logger: &L,
 733                 pending_events: &Mutex<Vec<events::Event>>, send_payment_along_path: &SP,
 734         )
 735         where
 736                 R::Target: Router,
 737                 ES::Target: EntropySource,
 738                 NS::Target: NodeSigner,
 739                 L::Target: Logger,
 740                 IH: Fn() -> InFlightHtlcs,
 741                 SP: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 742                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 743         {
 744                 match err {
 745                         PaymentSendFailure::AllFailedResendSafe(errs) => {
 746                                 Self::push_path_failed_evs_and_scids(payment_id, payment_hash, &mut route_params, route.paths, errs.into_iter().map(|e| Err(e)), pending_events);
 747                                 self.retry_payment_internal(payment_hash, payment_id, route_params, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
 748                         },
 749                         PaymentSendFailure::PartialFailure { failed_paths_retry: Some(mut retry), results, .. } => {
 750                                 Self::push_path_failed_evs_and_scids(payment_id, payment_hash, &mut retry, route.paths, results.into_iter(), pending_events);
 751                                 // Some paths were sent, even if we failed to send the full MPP value our recipient may
 752                                 // misbehave and claim the funds, at which point we have to consider the payment sent, so
 753                                 // return `Ok()` here, ignoring any retry errors.
 754                                 self.retry_payment_internal(payment_hash, payment_id, retry, router, first_hops, inflight_htlcs, entropy_source, node_signer, best_block_height, logger, pending_events, send_payment_along_path);
 755                         },
 756                         PaymentSendFailure::PartialFailure { failed_paths_retry: None, .. } => {
 757                                 // This may happen if we send a payment and some paths fail, but only due to a temporary
 758                                 // monitor failure or the like, implying they're really in-flight, but we haven't sent the
 759                                 // initial HTLC-Add messages yet.
 760                         },
 761                         PaymentSendFailure::PathParameterError(results) => {
 762                                 Self::push_path_failed_evs_and_scids(payment_id, payment_hash, &mut route_params, route.paths, results.into_iter(), pending_events);
 763                                 self.abandon_payment(payment_id, pending_events);
 764                         },
 765                         PaymentSendFailure::ParameterError(e) => {
 766                                 log_error!(logger, "Failed to send to route due to parameter error: {:?}. Your router is buggy", e);
 767                                 self.abandon_payment(payment_id, pending_events);
 768                         },
 769                         PaymentSendFailure::DuplicatePayment => debug_assert!(false), // unreachable
 770                 }
 771         }
 772
 773         fn push_path_failed_evs_and_scids<I: ExactSizeIterator + Iterator<Item = Result<(), APIError>>>(
 774                 payment_id: PaymentId, payment_hash: PaymentHash, route_params: &mut RouteParameters,
 775                 paths: Vec<Vec<RouteHop>>, path_results: I, pending_events: &Mutex<Vec<events::Event>>
 776         ) {
 777                 let mut events = pending_events.lock().unwrap();
 778                 debug_assert_eq!(paths.len(), path_results.len());
 779                 for (path, path_res) in paths.into_iter().zip(path_results) {
 780                         if let Err(e) = path_res {
 781                                 if let APIError::MonitorUpdateInProgress = e { continue }
 782                                 let mut failed_scid = None;
 783                                 if let APIError::ChannelUnavailable { .. } = e {
 784                                         let scid = path[0].short_channel_id;
 785                                         failed_scid = Some(scid);
 786                                         route_params.payment_params.previously_failed_channels.push(scid);
 787                                 }
 788                                 events.push(events::Event::PaymentPathFailed {
 789                                         payment_id: Some(payment_id),
 790                                         payment_hash,
 791                                         payment_failed_permanently: false,
 792                                         failure: events::PathFailure::InitialSend { err: e },
 793                                         path,
 794                                         short_channel_id: failed_scid,
 795                                         #[cfg(test)]
 796                                         error_code: None,
 797                                         #[cfg(test)]
 798                                         error_data: None,
 799                                 });
 800                         }
 801                 }
 802         }
 803
 804         pub(super) fn send_probe<ES: Deref, NS: Deref, F>(
 805                 &self, hops: Vec<RouteHop>, probing_cookie_secret: [u8; 32], entropy_source: &ES,
 806                 node_signer: &NS, best_block_height: u32, send_payment_along_path: F
 807         ) -> Result<(PaymentHash, PaymentId), PaymentSendFailure>
 808         where
 809                 ES::Target: EntropySource,
 810                 NS::Target: NodeSigner,
 811                 F: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 812                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 813         {
 814                 let payment_id = PaymentId(entropy_source.get_secure_random_bytes());
 815
 816                 let payment_hash = probing_cookie_from_id(&payment_id, probing_cookie_secret);
 817
 818                 if hops.len() < 2 {
 819                         return Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError {
 820                                 err: "No need probing a path with less than two hops".to_string()
 821                         }))
 822                 }
 823
 824                 let route = Route { paths: vec![hops], payment_params: None };
 825                 let onion_session_privs = self.add_new_pending_payment(payment_hash, None, payment_id, None, &route, None, None, entropy_source, best_block_height)?;
 826
 827                 match self.pay_route_internal(&route, payment_hash, &None, None, payment_id, None, onion_session_privs, node_signer, best_block_height, &send_payment_along_path) {
 828                         Ok(()) => Ok((payment_hash, payment_id)),
 829                         Err(e) => {
 830                                 self.remove_outbound_if_all_failed(payment_id, &e);
 831                                 Err(e)
 832                         }
 833                 }
 834         }
 835
 836         #[cfg(test)]
 837         pub(super) fn test_add_new_pending_payment<ES: Deref>(
 838                 &self, payment_hash: PaymentHash, payment_secret: Option<PaymentSecret>, payment_id: PaymentId,
 839                 route: &Route, retry_strategy: Option<Retry>, entropy_source: &ES, best_block_height: u32
 840         ) -> Result<Vec<[u8; 32]>, PaymentSendFailure> where ES::Target: EntropySource {
 841                 self.add_new_pending_payment(payment_hash, payment_secret, payment_id, None, route, retry_strategy, None, entropy_source, best_block_height)
 842         }
 843
 844         pub(super) fn add_new_pending_payment<ES: Deref>(
 845                 &self, payment_hash: PaymentHash, payment_secret: Option<PaymentSecret>, payment_id: PaymentId,
 846                 keysend_preimage: Option<PaymentPreimage>, route: &Route, retry_strategy: Option<Retry>,
 847                 payment_params: Option<PaymentParameters>, entropy_source: &ES, best_block_height: u32
 848         ) -> Result<Vec<[u8; 32]>, PaymentSendFailure> where ES::Target: EntropySource {
 849                 let mut onion_session_privs = Vec::with_capacity(route.paths.len());
 850                 for _ in 0..route.paths.len() {
 851                         onion_session_privs.push(entropy_source.get_secure_random_bytes());
 852                 }
 853
 854                 let mut pending_outbounds = self.pending_outbound_payments.lock().unwrap();
 855                 match pending_outbounds.entry(payment_id) {
 856                         hash_map::Entry::Occupied(_) => Err(PaymentSendFailure::DuplicatePayment),
 857                         hash_map::Entry::Vacant(entry) => {
 858                                 let payment = entry.insert(PendingOutboundPayment::Retryable {
 859                                         retry_strategy,
 860                                         attempts: PaymentAttempts::new(),
 861                                         payment_params,
 862                                         session_privs: HashSet::new(),
 863                                         pending_amt_msat: 0,
 864                                         pending_fee_msat: Some(0),
 865                                         payment_hash,
 866                                         payment_secret,
 867                                         keysend_preimage,
 868                                         starting_block_height: best_block_height,
 869                                         total_msat: route.get_total_amount(),
 870                                 });
 871
 872                                 for (path, session_priv_bytes) in route.paths.iter().zip(onion_session_privs.iter()) {
 873                                         assert!(payment.insert(*session_priv_bytes, path));
 874                                 }
 875
 876                                 Ok(onion_session_privs)
 877                         },
 878                 }
 879         }
 880
 881         fn pay_route_internal<NS: Deref, F>(
 882                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>,
 883                 keysend_preimage: Option<PaymentPreimage>, payment_id: PaymentId, recv_value_msat: Option<u64>,
 884                 onion_session_privs: Vec<[u8; 32]>, node_signer: &NS, best_block_height: u32,
 885                 send_payment_along_path: &F
 886         ) -> Result<(), PaymentSendFailure>
 887         where
 888                 NS::Target: NodeSigner,
 889                 F: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 890                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 891         {
 892                 if route.paths.len() < 1 {
 893                         return Err(PaymentSendFailure::ParameterError(APIError::InvalidRoute{err: "There must be at least one path to send over".to_owned()}));
 894                 }
 895                 if payment_secret.is_none() && route.paths.len() > 1 {
 896                         return Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError{err: "Payment secret is required for multi-path payments".to_owned()}));
 897                 }
 898                 let mut total_value = 0;
 899                 let our_node_id = node_signer.get_node_id(Recipient::Node).unwrap(); // TODO no unwrap
 900                 let mut path_errs = Vec::with_capacity(route.paths.len());
 901                 'path_check: for path in route.paths.iter() {
 902                         if path.len() < 1 || path.len() > 20 {
 903                                 path_errs.push(Err(APIError::InvalidRoute{err: "Path didn't go anywhere/had bogus size".to_owned()}));
 904                                 continue 'path_check;
 905                         }
 906                         for (idx, hop) in path.iter().enumerate() {
 907                                 if idx != path.len() - 1 && hop.pubkey == our_node_id {
 908                                         path_errs.push(Err(APIError::InvalidRoute{err: "Path went through us but wasn't a simple rebalance loop to us".to_owned()}));
 909                                         continue 'path_check;
 910                                 }
 911                         }
 912                         total_value += path.last().unwrap().fee_msat;
 913                         path_errs.push(Ok(()));
 914                 }
 915                 if path_errs.iter().any(|e| e.is_err()) {
 916                         return Err(PaymentSendFailure::PathParameterError(path_errs));
 917                 }
 918                 if let Some(amt_msat) = recv_value_msat {
 919                         total_value = amt_msat;
 920                 }
 921
 922                 let cur_height = best_block_height + 1;
 923                 let mut results = Vec::new();
 924                 debug_assert_eq!(route.paths.len(), onion_session_privs.len());
 925                 for (path, session_priv) in route.paths.iter().zip(onion_session_privs.into_iter()) {
 926                         let mut path_res = send_payment_along_path(&path, &payment_hash, payment_secret, total_value, cur_height, payment_id, &keysend_preimage, session_priv);
 927                         match path_res {
 928                                 Ok(_) => {},
 929                                 Err(APIError::MonitorUpdateInProgress) => {
 930                                         // While a MonitorUpdateInProgress is an Err(_), the payment is still
 931                                         // considered "in flight" and we shouldn't remove it from the
 932                                         // PendingOutboundPayment set.
 933                                 },
 934                                 Err(_) => {
 935                                         let mut pending_outbounds = self.pending_outbound_payments.lock().unwrap();
 936                                         if let Some(payment) = pending_outbounds.get_mut(&payment_id) {
 937                                                 let removed = payment.remove(&session_priv, Some(path));
 938                                                 debug_assert!(removed, "This can't happen as the payment has an entry for this path added by callers");
 939                                         } else {
 940                                                 debug_assert!(false, "This can't happen as the payment was added by callers");
 941                                                 path_res = Err(APIError::APIMisuseError { err: "Internal error: payment disappeared during processing. Please report this bug!".to_owned() });
 942                                         }
 943                                 }
 944                         }
 945                         results.push(path_res);
 946                 }
 947                 let mut has_ok = false;
 948                 let mut has_err = false;
 949                 let mut pending_amt_unsent = 0;
 950                 let mut max_unsent_cltv_delta = 0;
 951                 for (res, path) in results.iter().zip(route.paths.iter()) {
 952                         if res.is_ok() { has_ok = true; }
 953                         if res.is_err() { has_err = true; }
 954                         if let &Err(APIError::MonitorUpdateInProgress) = res {
 955                                 // MonitorUpdateInProgress is inherently unsafe to retry, so we call it a
 956                                 // PartialFailure.
 957                                 has_err = true;
 958                                 has_ok = true;
 959                         } else if res.is_err() {
 960                                 pending_amt_unsent += path.last().unwrap().fee_msat;
 961                                 max_unsent_cltv_delta = cmp::max(max_unsent_cltv_delta, path.last().unwrap().cltv_expiry_delta);
 962                         }
 963                 }
 964                 if has_err && has_ok {
 965                         Err(PaymentSendFailure::PartialFailure {
 966                                 results,
 967                                 payment_id,
 968                                 failed_paths_retry: if pending_amt_unsent != 0 {
 969                                         if let Some(payment_params) = &route.payment_params {
 970                                                 Some(RouteParameters {
 971                                                         payment_params: payment_params.clone(),
 972                                                         final_value_msat: pending_amt_unsent,
 973                                                 })
 974                                         } else { None }
 975                                 } else { None },
 976                         })
 977                 } else if has_err {
 978                         Err(PaymentSendFailure::AllFailedResendSafe(results.drain(..).map(|r| r.unwrap_err()).collect()))
 979                 } else {
 980                         Ok(())
 981                 }
 982         }
 983
 984         #[cfg(test)]
 985         pub(super) fn test_send_payment_internal<NS: Deref, F>(
 986                 &self, route: &Route, payment_hash: PaymentHash, payment_secret: &Option<PaymentSecret>,
 987                 keysend_preimage: Option<PaymentPreimage>, payment_id: PaymentId, recv_value_msat: Option<u64>,
 988                 onion_session_privs: Vec<[u8; 32]>, node_signer: &NS, best_block_height: u32,
 989                 send_payment_along_path: F
 990         ) -> Result<(), PaymentSendFailure>
 991         where
 992                 NS::Target: NodeSigner,
 993                 F: Fn(&Vec<RouteHop>, &PaymentHash, &Option<PaymentSecret>, u64, u32, PaymentId,
 994                         &Option<PaymentPreimage>, [u8; 32]) -> Result<(), APIError>
 995         {
 996                 self.pay_route_internal(route, payment_hash, payment_secret, keysend_preimage, payment_id,
 997                         recv_value_msat, onion_session_privs, node_signer, best_block_height,
 998                         &send_payment_along_path)
 999                         .map_err(|e| { self.remove_outbound_if_all_failed(payment_id, &e); e })
1000         }
1001
1002         // If we failed to send any paths, remove the new PaymentId from the `pending_outbound_payments`
1003         // map as the payment is free to be resent.
1004         fn remove_outbound_if_all_failed(&self, payment_id: PaymentId, err: &PaymentSendFailure) {
1005                 if let &PaymentSendFailure::AllFailedResendSafe(_) = err {
1006                         let removed = self.pending_outbound_payments.lock().unwrap().remove(&payment_id).is_some();
1007                         debug_assert!(removed, "We should always have a pending payment to remove here");
1008                 }
1009         }
1010
1011         pub(super) fn claim_htlc<L: Deref>(
1012                 &self, payment_id: PaymentId, payment_preimage: PaymentPreimage, session_priv: SecretKey,
1013                 path: Vec<RouteHop>, from_onchain: bool, pending_events: &Mutex<Vec<events::Event>>, logger: &L
1014         ) where L::Target: Logger {
1015                 let mut session_priv_bytes = [0; 32];
1016                 session_priv_bytes.copy_from_slice(&session_priv[..]);
1017                 let mut outbounds = self.pending_outbound_payments.lock().unwrap();
1018                 let mut pending_events = pending_events.lock().unwrap();
1019                 if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(payment_id) {
1020                         if !payment.get().is_fulfilled() {
1021                                 let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0).into_inner());
1022                                 let fee_paid_msat = payment.get().get_pending_fee_msat();
1023                                 pending_events.push(
1024                                         events::Event::PaymentSent {
1025                                                 payment_id: Some(payment_id),
1026                                                 payment_preimage,
1027                                                 payment_hash,
1028                                                 fee_paid_msat,
1029                                         }
1030                                 );
1031                                 payment.get_mut().mark_fulfilled();
1032                         }
1033
1034                         if from_onchain {
1035                                 // We currently immediately remove HTLCs which were fulfilled on-chain.
1036                                 // This could potentially lead to removing a pending payment too early,
1037                                 // with a reorg of one block causing us to re-add the fulfilled payment on
1038                                 // restart.
1039                                 // TODO: We should have a second monitor event that informs us of payments
1040                                 // irrevocably fulfilled.
1041                                 if payment.get_mut().remove(&session_priv_bytes, Some(&path)) {
1042                                         let payment_hash = Some(PaymentHash(Sha256::hash(&payment_preimage.0).into_inner()));
1043                                         pending_events.push(
1044                                                 events::Event::PaymentPathSuccessful {
1045                                                         payment_id,
1046                                                         payment_hash,
1047                                                         path,
1048                                                 }
1049                                         );
1050                                 }
1051                         }
1052                 } else {
1053                         log_trace!(logger, "Received duplicative fulfill for HTLC with payment_preimage {}", log_bytes!(payment_preimage.0));
1054                 }
1055         }
1056
1057         pub(super) fn finalize_claims(&self, sources: Vec<HTLCSource>, pending_events: &Mutex<Vec<events::Event>>) {
1058                 let mut outbounds = self.pending_outbound_payments.lock().unwrap();
1059                 let mut pending_events = pending_events.lock().unwrap();
1060                 for source in sources {
1061                         if let HTLCSource::OutboundRoute { session_priv, payment_id, path, .. } = source {
1062                                 let mut session_priv_bytes = [0; 32];
1063                                 session_priv_bytes.copy_from_slice(&session_priv[..]);
1064                                 if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(payment_id) {
1065                                         assert!(payment.get().is_fulfilled());
1066                                         if payment.get_mut().remove(&session_priv_bytes, None) {
1067                                                 pending_events.push(
1068                                                         events::Event::PaymentPathSuccessful {
1069                                                                 payment_id,
1070                                                                 payment_hash: payment.get().payment_hash(),
1071                                                                 path,
1072                                                         }
1073                                                 );
1074                                         }
1075                                 }
1076                         }
1077                 }
1078         }
1079
1080         pub(super) fn remove_stale_resolved_payments(&self, pending_events: &Mutex<Vec<events::Event>>) {
1081                 // If an outbound payment was completed, and no pending HTLCs remain, we should remove it
1082                 // from the map. However, if we did that immediately when the last payment HTLC is claimed,
1083                 // this could race the user making a duplicate send_payment call and our idempotency
1084                 // guarantees would be violated. Instead, we wait a few timer ticks to do the actual
1085                 // removal. This should be more than sufficient to ensure the idempotency of any
1086                 // `send_payment` calls that were made at the same time the `PaymentSent` event was being
1087                 // processed.
1088                 let mut pending_outbound_payments = self.pending_outbound_payments.lock().unwrap();
1089                 let pending_events = pending_events.lock().unwrap();
1090                 pending_outbound_payments.retain(|payment_id, payment| {
1091                         if let PendingOutboundPayment::Fulfilled { session_privs, timer_ticks_without_htlcs, .. } = payment {
1092                                 let mut no_remaining_entries = session_privs.is_empty();
1093                                 if no_remaining_entries {
1094                                         for ev in pending_events.iter() {
1095                                                 match ev {
1096                                                         events::Event::PaymentSent { payment_id: Some(ev_payment_id), .. } |
1097                                                                 events::Event::PaymentPathSuccessful { payment_id: ev_payment_id, .. } |
1098                                                                 events::Event::PaymentPathFailed { payment_id: Some(ev_payment_id), .. } => {
1099                                                                         if payment_id == ev_payment_id {
1100                                                                                 no_remaining_entries = false;
1101                                                                                 break;
1102                                                                         }
1103                                                                 },
1104                                                         _ => {},
1105                                                 }
1106                                         }
1107                                 }
1108                                 if no_remaining_entries {
1109                                         *timer_ticks_without_htlcs += 1;
1110                                         *timer_ticks_without_htlcs <= IDEMPOTENCY_TIMEOUT_TICKS
1111                                 } else {
1112                                         *timer_ticks_without_htlcs = 0;
1113                                         true
1114                                 }
1115                         } else { true }
1116                 });
1117         }
1118
1119         // Returns a bool indicating whether a PendingHTLCsForwardable event should be generated.
1120         pub(super) fn fail_htlc<L: Deref>(
1121                 &self, source: &HTLCSource, payment_hash: &PaymentHash, onion_error: &HTLCFailReason,
1122                 path: &Vec<RouteHop>, session_priv: &SecretKey, payment_id: &PaymentId,
1123                 probing_cookie_secret: [u8; 32], secp_ctx: &Secp256k1<secp256k1::All>,
1124                 pending_events: &Mutex<Vec<events::Event>>, logger: &L
1125         ) -> bool where L::Target: Logger {
1126                 #[cfg(test)]
1127                 let (network_update, short_channel_id, payment_retryable, onion_error_code, onion_error_data) = onion_error.decode_onion_failure(secp_ctx, logger, &source);
1128                 #[cfg(not(test))]
1129                 let (network_update, short_channel_id, payment_retryable, _, _) = onion_error.decode_onion_failure(secp_ctx, logger, &source);
1130
1131                 let payment_is_probe = payment_is_probe(payment_hash, &payment_id, probing_cookie_secret);
1132                 let mut session_priv_bytes = [0; 32];
1133                 session_priv_bytes.copy_from_slice(&session_priv[..]);
1134                 let mut outbounds = self.pending_outbound_payments.lock().unwrap();
1135
1136                 // If any payments already need retry, there's no need to generate a redundant
1137                 // `PendingHTLCsForwardable`.
1138                 let already_awaiting_retry = outbounds.iter().any(|(_, pmt)| {
1139                         let mut awaiting_retry = false;
1140                         if pmt.is_auto_retryable_now() {
1141                                 if let PendingOutboundPayment::Retryable { pending_amt_msat, total_msat, .. } = pmt {
1142                                         if pending_amt_msat < total_msat {
1143                                                 awaiting_retry = true;
1144                                         }
1145                                 }
1146                         }
1147                         awaiting_retry
1148                 });
1149
1150                 let mut full_failure_ev = None;
1151                 let mut pending_retry_ev = false;
1152                 let attempts_remaining = if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(*payment_id) {
1153                         if !payment.get_mut().remove(&session_priv_bytes, Some(&path)) {
1154                                 log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1155                                 return false
1156                         }
1157                         if payment.get().is_fulfilled() {
1158                                 log_trace!(logger, "Received failure of HTLC with payment_hash {} after payment completion", log_bytes!(payment_hash.0));
1159                                 return false
1160                         }
1161                         let mut is_retryable_now = payment.get().is_auto_retryable_now();
1162                         if let Some(scid) = short_channel_id {
1163                                 // TODO: If we decided to blame ourselves (or one of our channels) in
1164                                 // process_onion_failure we should close that channel as it implies our
1165                                 // next-hop is needlessly blaming us!
1166                                 payment.get_mut().insert_previously_failed_scid(scid);
1167                         }
1168
1169                         if payment_is_probe || !is_retryable_now || !payment_retryable {
1170                                 let _ = payment.get_mut().mark_abandoned(); // we'll only Err if it's a legacy payment
1171                                 is_retryable_now = false;
1172                         }
1173                         if payment.get().remaining_parts() == 0 {
1174                                 if payment.get().abandoned() {
1175                                         if !payment_is_probe {
1176                                                 full_failure_ev = Some(events::Event::PaymentFailed {
1177                                                         payment_id: *payment_id,
1178                                                         payment_hash: payment.get().payment_hash().expect("PendingOutboundPayments::RetriesExceeded always has a payment hash set"),
1179                                                 });
1180                                         }
1181                                         payment.remove();
1182                                 }
1183                         }
1184                         is_retryable_now
1185                 } else {
1186                         log_trace!(logger, "Received duplicative fail for HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1187                         return false
1188                 };
1189                 core::mem::drop(outbounds);
1190                 log_trace!(logger, "Failing outbound payment HTLC with payment_hash {}", log_bytes!(payment_hash.0));
1191
1192                 let path_failure = {
1193                         if payment_is_probe {
1194                                 if !payment_retryable {
1195                                         events::Event::ProbeSuccessful {
1196                                                 payment_id: *payment_id,
1197                                                 payment_hash: payment_hash.clone(),
1198                                                 path: path.clone(),
1199                                         }
1200                                 } else {
1201                                         events::Event::ProbeFailed {
1202                                                 payment_id: *payment_id,
1203                                                 payment_hash: payment_hash.clone(),
1204                                                 path: path.clone(),
1205                                                 short_channel_id,
1206                                         }
1207                                 }
1208                         } else {
1209                                 // If we miss abandoning the payment above, we *must* generate an event here or else the
1210                                 // payment will sit in our outbounds forever.
1211                                 if attempts_remaining && !already_awaiting_retry {
1212                                         debug_assert!(full_failure_ev.is_none());
1213                                         pending_retry_ev = true;
1214                                 }
1215                                 events::Event::PaymentPathFailed {
1216                                         payment_id: Some(*payment_id),
1217                                         payment_hash: payment_hash.clone(),
1218                                         payment_failed_permanently: !payment_retryable,
1219                                         failure: events::PathFailure::OnPath { network_update },
1220                                         path: path.clone(),
1221                                         short_channel_id,
1222                                         #[cfg(test)]
1223                                         error_code: onion_error_code,
1224                                         #[cfg(test)]
1225                                         error_data: onion_error_data
1226                                 }
1227                         }
1228                 };
1229                 let mut pending_events = pending_events.lock().unwrap();
1230                 pending_events.push(path_failure);
1231                 if let Some(ev) = full_failure_ev { pending_events.push(ev); }
1232                 pending_retry_ev
1233         }
1234
1235         pub(super) fn abandon_payment(
1236                 &self, payment_id: PaymentId, pending_events: &Mutex<Vec<events::Event>>
1237         ) {
1238                 let mut outbounds = self.pending_outbound_payments.lock().unwrap();
1239                 if let hash_map::Entry::Occupied(mut payment) = outbounds.entry(payment_id) {
1240                         if let Ok(()) = payment.get_mut().mark_abandoned() {
1241                                 if payment.get().remaining_parts() == 0 {
1242                                         pending_events.lock().unwrap().push(events::Event::PaymentFailed {
1243                                                 payment_id,
1244                                                 payment_hash: payment.get().payment_hash().expect("PendingOutboundPayments::RetriesExceeded always has a payment hash set"),
1245                                         });
1246                                         payment.remove();
1247                                 }
1248                         }
1249                 }
1250         }
1251
1252         #[cfg(test)]
1253         pub fn has_pending_payments(&self) -> bool {
1254                 !self.pending_outbound_payments.lock().unwrap().is_empty()
1255         }
1256
1257         #[cfg(test)]
1258         pub fn clear_pending_payments(&self) {
1259                 self.pending_outbound_payments.lock().unwrap().clear()
1260         }
1261 }
1262
1263 /// Returns whether a payment with the given [`PaymentHash`] and [`PaymentId`] is, in fact, a
1264 /// payment probe.
1265 pub(super) fn payment_is_probe(payment_hash: &PaymentHash, payment_id: &PaymentId,
1266         probing_cookie_secret: [u8; 32]) -> bool
1267 {
1268         let target_payment_hash = probing_cookie_from_id(payment_id, probing_cookie_secret);
1269         target_payment_hash == *payment_hash
1270 }
1271
1272 /// Returns the 'probing cookie' for the given [`PaymentId`].
1273 fn probing_cookie_from_id(payment_id: &PaymentId, probing_cookie_secret: [u8; 32]) -> PaymentHash {
1274         let mut preimage = [0u8; 64];
1275         preimage[..32].copy_from_slice(&probing_cookie_secret);
1276         preimage[32..].copy_from_slice(&payment_id.0);
1277         PaymentHash(Sha256::hash(&preimage).into_inner())
1278 }
1279
1280 impl_writeable_tlv_based_enum_upgradable!(PendingOutboundPayment,
1281         (0, Legacy) => {
1282                 (0, session_privs, required),
1283         },
1284         (1, Fulfilled) => {
1285                 (0, session_privs, required),
1286                 (1, payment_hash, option),
1287                 (3, timer_ticks_without_htlcs, (default_value, 0)),
1288         },
1289         (2, Retryable) => {
1290                 (0, session_privs, required),
1291                 (1, pending_fee_msat, option),
1292                 (2, payment_hash, required),
1293                 // Note that while we "default" payment_param's final CLTV expiry delta to 0 we should
1294                 // never see it - `payment_params` was added here after the field was added/required.
1295                 (3, payment_params, (option: ReadableArgs, 0)),
1296                 (4, payment_secret, option),
1297                 (5, keysend_preimage, option),
1298                 (6, total_msat, required),
1299                 (8, pending_amt_msat, required),
1300                 (10, starting_block_height, required),
1301                 (not_written, retry_strategy, (static_value, None)),
1302                 (not_written, attempts, (static_value, PaymentAttempts::new())),
1303         },
1304         (3, Abandoned) => {
1305                 (0, session_privs, required),
1306                 (2, payment_hash, required),
1307         },
1308 );
1309
1310 #[cfg(test)]
1311 mod tests {
1312         use bitcoin::network::constants::Network;
1313         use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
1314
1315         use crate::events::{Event, PathFailure};
1316         use crate::ln::PaymentHash;
1317         use crate::ln::channelmanager::PaymentId;
1318         use crate::ln::features::{ChannelFeatures, NodeFeatures};
1319         use crate::ln::msgs::{ErrorAction, LightningError};
1320         use crate::ln::outbound_payment::{OutboundPayments, Retry, RetryableSendFailure};
1321         use crate::routing::gossip::NetworkGraph;
1322         use crate::routing::router::{InFlightHtlcs, PaymentParameters, Route, RouteHop, RouteParameters};
1323         use crate::sync::{Arc, Mutex};
1324         use crate::util::errors::APIError;
1325         use crate::util::test_utils;
1326
1327         #[test]
1328         #[cfg(feature = "std")]
1329         fn fails_paying_after_expiration() {
1330                 do_fails_paying_after_expiration(false);
1331                 do_fails_paying_after_expiration(true);
1332         }
1333         #[cfg(feature = "std")]
1334         fn do_fails_paying_after_expiration(on_retry: bool) {
1335                 let outbound_payments = OutboundPayments::new();
1336                 let logger = test_utils::TestLogger::new();
1337                 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
1338                 let scorer = Mutex::new(test_utils::TestScorer::new());
1339                 let router = test_utils::TestRouter::new(network_graph, &scorer);
1340                 let secp_ctx = Secp256k1::new();
1341                 let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
1342
1343                 let past_expiry_time = std::time::SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() - 2;
1344                 let payment_params = PaymentParameters::from_node_id(
1345                                 PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()),
1346                                 0
1347                         ).with_expiry_time(past_expiry_time);
1348                 let expired_route_params = RouteParameters {
1349                         payment_params,
1350                         final_value_msat: 0,
1351                 };
1352                 let pending_events = Mutex::new(Vec::new());
1353                 if on_retry {
1354                         outbound_payments.add_new_pending_payment(PaymentHash([0; 32]), None, PaymentId([0; 32]), None,
1355                         &Route { paths: vec![], payment_params: None }, Some(Retry::Attempts(1)),
1356                         Some(expired_route_params.payment_params.clone()), &&keys_manager, 0).unwrap();
1357                         outbound_payments.retry_payment_internal(
1358                                 PaymentHash([0; 32]), PaymentId([0; 32]), expired_route_params, &&router, vec![],
1359                                 &|| InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1360                                 &pending_events, &|_, _, _, _, _, _, _, _| Ok(()));
1361                         let events = pending_events.lock().unwrap();
1362                         assert_eq!(events.len(), 1);
1363                         if let Event::PaymentFailed { .. } = events[0] { } else { panic!("Unexpected event"); }
1364                 } else {
1365                         let err = outbound_payments.send_payment(
1366                                 PaymentHash([0; 32]), &None, PaymentId([0; 32]), Retry::Attempts(0), expired_route_params,
1367                                 &&router, vec![], || InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1368                                 &pending_events, |_, _, _, _, _, _, _, _| Ok(())).unwrap_err();
1369                         if let RetryableSendFailure::PaymentExpired = err { } else { panic!("Unexpected error"); }
1370                 }
1371         }
1372
1373         #[test]
1374         fn find_route_error() {
1375                 do_find_route_error(false);
1376                 do_find_route_error(true);
1377         }
1378         fn do_find_route_error(on_retry: bool) {
1379                 let outbound_payments = OutboundPayments::new();
1380                 let logger = test_utils::TestLogger::new();
1381                 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
1382                 let scorer = Mutex::new(test_utils::TestScorer::new());
1383                 let router = test_utils::TestRouter::new(network_graph, &scorer);
1384                 let secp_ctx = Secp256k1::new();
1385                 let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
1386
1387                 let payment_params = PaymentParameters::from_node_id(
1388                         PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap()), 0);
1389                 let route_params = RouteParameters {
1390                         payment_params,
1391                         final_value_msat: 0,
1392                 };
1393                 router.expect_find_route(route_params.clone(),
1394                         Err(LightningError { err: String::new(), action: ErrorAction::IgnoreError }));
1395
1396                 let pending_events = Mutex::new(Vec::new());
1397                 if on_retry {
1398                         outbound_payments.add_new_pending_payment(PaymentHash([0; 32]), None, PaymentId([0; 32]), None,
1399                                 &Route { paths: vec![], payment_params: None }, Some(Retry::Attempts(1)),
1400                                 Some(route_params.payment_params.clone()), &&keys_manager, 0).unwrap();
1401                         outbound_payments.retry_payment_internal(
1402                                 PaymentHash([0; 32]), PaymentId([0; 32]), route_params, &&router, vec![],
1403                                 &|| InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1404                                 &pending_events, &|_, _, _, _, _, _, _, _| Ok(()));
1405                         let events = pending_events.lock().unwrap();
1406                         assert_eq!(events.len(), 1);
1407                         if let Event::PaymentFailed { .. } = events[0] { } else { panic!("Unexpected event"); }
1408                 } else {
1409                         let err = outbound_payments.send_payment(
1410                                 PaymentHash([0; 32]), &None, PaymentId([0; 32]), Retry::Attempts(0), route_params,
1411                                 &&router, vec![], || InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1412                                 &pending_events, |_, _, _, _, _, _, _, _| Ok(())).unwrap_err();
1413                         if let RetryableSendFailure::RouteNotFound = err {
1414                         } else { panic!("Unexpected error"); }
1415                 }
1416         }
1417
1418         #[test]
1419         fn initial_send_payment_path_failed_evs() {
1420                 let outbound_payments = OutboundPayments::new();
1421                 let logger = test_utils::TestLogger::new();
1422                 let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, &logger));
1423                 let scorer = Mutex::new(test_utils::TestScorer::new());
1424                 let router = test_utils::TestRouter::new(network_graph, &scorer);
1425                 let secp_ctx = Secp256k1::new();
1426                 let keys_manager = test_utils::TestKeysInterface::new(&[0; 32], Network::Testnet);
1427
1428                 let sender_pk = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
1429                 let receiver_pk = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[43; 32]).unwrap());
1430                 let payment_params = PaymentParameters::from_node_id(sender_pk, 0);
1431                 let route_params = RouteParameters {
1432                         payment_params: payment_params.clone(),
1433                         final_value_msat: 0,
1434                 };
1435                 let failed_scid = 42;
1436                 let route = Route {
1437                         paths: vec![vec![RouteHop {
1438                                 pubkey: receiver_pk,
1439                                 node_features: NodeFeatures::empty(),
1440                                 short_channel_id: failed_scid,
1441                                 channel_features: ChannelFeatures::empty(),
1442                                 fee_msat: 0,
1443                                 cltv_expiry_delta: 0,
1444                         }]],
1445                         payment_params: Some(payment_params),
1446                 };
1447                 router.expect_find_route(route_params.clone(), Ok(route.clone()));
1448                 let mut route_params_w_failed_scid = route_params.clone();
1449                 route_params_w_failed_scid.payment_params.previously_failed_channels.push(failed_scid);
1450                 router.expect_find_route(route_params_w_failed_scid, Ok(route.clone()));
1451                 router.expect_find_route(route_params.clone(), Ok(route.clone()));
1452                 router.expect_find_route(route_params.clone(), Ok(route.clone()));
1453
1454                 // Ensure that a ChannelUnavailable error will result in blaming an scid in the
1455                 // PaymentPathFailed event.
1456                 let pending_events = Mutex::new(Vec::new());
1457                 outbound_payments.send_payment(
1458                         PaymentHash([0; 32]), &None, PaymentId([0; 32]), Retry::Attempts(0), route_params.clone(),
1459                         &&router, vec![], || InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1460                         &pending_events,
1461                         |_, _, _, _, _, _, _, _| Err(APIError::ChannelUnavailable { err: "test".to_owned() }))
1462                         .unwrap();
1463                 let mut events = pending_events.lock().unwrap();
1464                 assert_eq!(events.len(), 2);
1465                 if let Event::PaymentPathFailed {
1466                         short_channel_id,
1467                         failure: PathFailure::InitialSend { err: APIError::ChannelUnavailable { .. }}, .. } = events[0]
1468                 {
1469                         assert_eq!(short_channel_id, Some(failed_scid));
1470                 } else { panic!("Unexpected event"); }
1471                 if let Event::PaymentFailed { .. } = events[1] { } else { panic!("Unexpected event"); }
1472                 events.clear();
1473                 core::mem::drop(events);
1474
1475                 // Ensure that a MonitorUpdateInProgress "error" will not result in a PaymentPathFailed event.
1476                 outbound_payments.send_payment(
1477                         PaymentHash([0; 32]), &None, PaymentId([0; 32]), Retry::Attempts(0), route_params.clone(),
1478                         &&router, vec![], || InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1479                         &pending_events, |_, _, _, _, _, _, _, _| Err(APIError::MonitorUpdateInProgress))
1480                         .unwrap();
1481                 {
1482                         let events = pending_events.lock().unwrap();
1483                         assert_eq!(events.len(), 0);
1484                 }
1485
1486                 // Ensure that any other error will result in a PaymentPathFailed event but no blamed scid.
1487                 outbound_payments.send_payment(
1488                         PaymentHash([0; 32]), &None, PaymentId([1; 32]), Retry::Attempts(0), route_params.clone(),
1489                         &&router, vec![], || InFlightHtlcs::new(), &&keys_manager, &&keys_manager, 0, &&logger,
1490                         &pending_events,
1491                         |_, _, _, _, _, _, _, _| Err(APIError::APIMisuseError { err: "test".to_owned() }))
1492                         .unwrap();
1493                 let events = pending_events.lock().unwrap();
1494                 assert_eq!(events.len(), 2);
1495                 if let Event::PaymentPathFailed {
1496                         short_channel_id,
1497                         failure: PathFailure::InitialSend { err: APIError::APIMisuseError { .. }}, .. } = events[0]
1498                 {
1499                         assert_eq!(short_channel_id, None);
1500                 } else { panic!("Unexpected event"); }
1501                 if let Event::PaymentFailed { .. } = events[1] { } else { panic!("Unexpected event"); }
1502         }
1503 }