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