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