_ Git - rust-lightning/blob - lightning/src/ln/payment_tests.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 //! Tests that test the payment retry logic in ChannelManager, including various edge-cases around
  11 //! serialization ordering between ChannelManager/ChannelMonitors and ensuring we can still retry
  12 //! payments thereafter.
  13
  14 use crate::chain::{ChannelMonitorUpdateStatus, Confirm, Listen};
  15 use crate::chain::channelmonitor::{ANTI_REORG_DELAY, HTLC_FAIL_BACK_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS};
  16 use crate::sign::EntropySource;
  17 use crate::events::{ClosureReason, Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, PathFailure, PaymentFailureReason, PaymentPurpose};
  18 use crate::ln::channel::{EXPIRE_PREV_CONFIG_TICKS, commit_tx_fee_msat, get_holder_selected_channel_reserve_satoshis, ANCHOR_OUTPUT_VALUE_SATOSHI};
  19 use crate::ln::channelmanager::{BREAKDOWN_TIMEOUT, MPP_TIMEOUT_TICKS, MIN_CLTV_EXPIRY_DELTA, PaymentId, PaymentSendFailure, RecentPaymentDetails, RecipientOnionFields, HTLCForwardInfo, PendingHTLCRouting, PendingAddHTLCInfo};
  20 use crate::ln::features::{Bolt11InvoiceFeatures, ChannelTypeFeatures};
  21 use crate::ln::msgs;
  22 use crate::ln::types::{ChannelId, PaymentHash, PaymentSecret, PaymentPreimage};
  23 use crate::ln::msgs::ChannelMessageHandler;
  24 use crate::ln::onion_utils;
  25 use crate::ln::outbound_payment::{IDEMPOTENCY_TIMEOUT_TICKS, Retry};
  26 use crate::routing::gossip::{EffectiveCapacity, RoutingFees};
  27 use crate::routing::router::{get_route, Path, PaymentParameters, Route, Router, RouteHint, RouteHintHop, RouteHop, RouteParameters, find_route};
  28 use crate::routing::scoring::ChannelUsage;
  29 use crate::util::config::UserConfig;
  30 use crate::util::test_utils;
  31 use crate::util::errors::APIError;
  32 use crate::util::ser::Writeable;
  33 use crate::util::string::UntrustedString;
  34
  35 use bitcoin::hashes::Hash;
  36 use bitcoin::hashes::sha256::Hash as Sha256;
  37 use bitcoin::network::Network;
  38 use bitcoin::secp256k1::{Secp256k1, SecretKey};
  39
  40 use crate::prelude::*;
  41
  42 use crate::ln::functional_test_utils;
  43 use crate::ln::functional_test_utils::*;
  44 use crate::routing::gossip::NodeId;
  45
  46 #[cfg(feature = "std")]
  47 use {
  48         crate::util::time::tests::SinceEpoch,
  49         std::time::{SystemTime, Instant, Duration},
  50 };
  51
  52 #[test]
  53 fn mpp_failure() {
  54         let chanmon_cfgs = create_chanmon_cfgs(4);
  55         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
  56         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
  57         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
  58
  59         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1).0.contents.short_channel_id;
  60         let chan_2_id = create_announced_chan_between_nodes(&nodes, 0, 2).0.contents.short_channel_id;
  61         let chan_3_id = create_announced_chan_between_nodes(&nodes, 1, 3).0.contents.short_channel_id;
  62         let chan_4_id = create_announced_chan_between_nodes(&nodes, 2, 3).0.contents.short_channel_id;
  63
  64         let (mut route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[3], 100000);
  65         let path = route.paths[0].clone();
  66         route.paths.push(path);
  67         route.paths[0].hops[0].pubkey = nodes[1].node.get_our_node_id();
  68         route.paths[0].hops[0].short_channel_id = chan_1_id;
  69         route.paths[0].hops[1].short_channel_id = chan_3_id;
  70         route.paths[1].hops[0].pubkey = nodes[2].node.get_our_node_id();
  71         route.paths[1].hops[0].short_channel_id = chan_2_id;
  72         route.paths[1].hops[1].short_channel_id = chan_4_id;
  73         send_along_route_with_secret(&nodes[0], route, &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], 200_000, payment_hash, payment_secret);
  74         fail_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_hash);
  75 }
  76
  77 #[test]
  78 fn mpp_retry() {
  79         let chanmon_cfgs = create_chanmon_cfgs(4);
  80         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
  81         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
  82         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
  83
  84         let (chan_1_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 0, 1);
  85         let (chan_2_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 0, 2);
  86         let (chan_3_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 1, 3);
  87         let (chan_4_update, _, chan_4_id, _) = create_announced_chan_between_nodes(&nodes, 3, 2);
  88         // Rebalance
  89         send_payment(&nodes[3], &vec!(&nodes[2])[..], 1_500_000);
  90
  91         let amt_msat = 1_000_000;
  92         let max_total_routing_fee_msat = 50_000;
  93         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
  94                 .with_bolt11_features(nodes[3].node.bolt11_invoice_features()).unwrap();
  95         let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(
  96                 nodes[0], nodes[3], payment_params, amt_msat, Some(max_total_routing_fee_msat));
  97         let path = route.paths[0].clone();
  98         route.paths.push(path);
  99         route.paths[0].hops[0].pubkey = nodes[1].node.get_our_node_id();
 100         route.paths[0].hops[0].short_channel_id = chan_1_update.contents.short_channel_id;
 101         route.paths[0].hops[1].short_channel_id = chan_3_update.contents.short_channel_id;
 102         route.paths[1].hops[0].pubkey = nodes[2].node.get_our_node_id();
 103         route.paths[1].hops[0].short_channel_id = chan_2_update.contents.short_channel_id;
 104         route.paths[1].hops[1].short_channel_id = chan_4_update.contents.short_channel_id;
 105
 106         // Initiate the MPP payment.
 107         let payment_id = PaymentId(payment_hash.0);
 108         let mut route_params = route.route_params.clone().unwrap();
 109
 110         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
 111         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
 112                 payment_id, route_params.clone(), Retry::Attempts(1)).unwrap();
 113         check_added_monitors!(nodes[0], 2); // one monitor per path
 114         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 115         assert_eq!(events.len(), 2);
 116
 117         // Pass half of the payment along the success path.
 118         let success_path_msgs = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 119         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 2_000_000, payment_hash, Some(payment_secret), success_path_msgs, false, None);
 120
 121         // Add the HTLC along the first hop.
 122         let fail_path_msgs_1 = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 123         let send_event = SendEvent::from_event(fail_path_msgs_1);
 124         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
 125         commitment_signed_dance!(nodes[2], nodes[0], &send_event.commitment_msg, false);
 126
 127         // Attempt to forward the payment and complete the 2nd path's failure.
 128         expect_pending_htlcs_forwardable!(&nodes[2]);
 129         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[2], vec![HTLCDestination::NextHopChannel { node_id: Some(nodes[3].node.get_our_node_id()), channel_id: chan_4_id }]);
 130         let htlc_updates = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id());
 131         assert!(htlc_updates.update_add_htlcs.is_empty());
 132         assert_eq!(htlc_updates.update_fail_htlcs.len(), 1);
 133         assert!(htlc_updates.update_fulfill_htlcs.is_empty());
 134         assert!(htlc_updates.update_fail_malformed_htlcs.is_empty());
 135         check_added_monitors!(nodes[2], 1);
 136         nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &htlc_updates.update_fail_htlcs[0]);
 137         commitment_signed_dance!(nodes[0], nodes[2], htlc_updates.commitment_signed, false);
 138         let mut events = nodes[0].node.get_and_clear_pending_events();
 139         match events[1] {
 140                 Event::PendingHTLCsForwardable { .. } => {},
 141                 _ => panic!("Unexpected event")
 142         }
 143         events.remove(1);
 144         expect_payment_failed_conditions_event(events, payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain());
 145
 146         // Rebalance the channel so the second half of the payment can succeed.
 147         send_payment(&nodes[3], &vec!(&nodes[2])[..], 1_500_000);
 148
 149         // Retry the second half of the payment and make sure it succeeds.
 150         route.paths.remove(0);
 151         route_params.final_value_msat = 1_000_000;
 152         route_params.payment_params.previously_failed_channels.push(chan_4_update.contents.short_channel_id);
 153         // Check the remaining max total routing fee for the second attempt is 50_000 - 1_000 msat fee
 154         // used by the first path
 155         route_params.max_total_routing_fee_msat = Some(max_total_routing_fee_msat - 1_000);
 156         route.route_params = Some(route_params.clone());
 157         nodes[0].router.expect_find_route(route_params, Ok(route));
 158         nodes[0].node.process_pending_htlc_forwards();
 159         check_added_monitors!(nodes[0], 1);
 160         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 161         assert_eq!(events.len(), 1);
 162         pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 2_000_000, payment_hash, Some(payment_secret), events.pop().unwrap(), true, None);
 163         claim_payment_along_route(
 164                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], payment_preimage)
 165         );
 166 }
 167
 168 #[test]
 169 fn mpp_retry_overpay() {
 170         // We create an MPP scenario with two paths in which we need to overpay to reach
 171         // htlc_minimum_msat. We then fail the overpaid path and check that on retry our
 172         // max_total_routing_fee_msat only accounts for the path's fees, but not for the fees overpaid
 173         // in the first attempt.
 174         let chanmon_cfgs = create_chanmon_cfgs(4);
 175         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 176         let mut user_config = test_default_channel_config();
 177         user_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100;
 178         let mut limited_config_1 = user_config.clone();
 179         limited_config_1.channel_handshake_config.our_htlc_minimum_msat = 35_000_000;
 180         let mut limited_config_2 = user_config.clone();
 181         limited_config_2.channel_handshake_config.our_htlc_minimum_msat = 34_500_000;
 182         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs,
 183                 &[Some(user_config), Some(limited_config_1), Some(limited_config_2), Some(user_config)]);
 184         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 185
 186         let (chan_1_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 40_000, 0);
 187         let (chan_2_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 40_000, 0);
 188         let (_chan_3_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 40_000, 0);
 189         let (chan_4_update, _, chan_4_id, _) = create_announced_chan_between_nodes_with_value(&nodes, 3, 2, 40_000, 0);
 190
 191         let amt_msat = 70_000_000;
 192         let max_total_routing_fee_msat = Some(1_000_000);
 193
 194         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
 195                 .with_bolt11_features(nodes[3].node.bolt11_invoice_features()).unwrap();
 196         let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(
 197                 nodes[0], nodes[3], payment_params, amt_msat, max_total_routing_fee_msat);
 198
 199         // Check we overpay on the second path which we're about to fail.
 200         assert_eq!(chan_1_update.contents.fee_proportional_millionths, 0);
 201         let overpaid_amount_1 = route.paths[0].fee_msat() as u32 - chan_1_update.contents.fee_base_msat;
 202         assert_eq!(overpaid_amount_1, 0);
 203
 204         assert_eq!(chan_2_update.contents.fee_proportional_millionths, 0);
 205         let overpaid_amount_2 = route.paths[1].fee_msat() as u32 - chan_2_update.contents.fee_base_msat;
 206
 207         let total_overpaid_amount = overpaid_amount_1 + overpaid_amount_2;
 208
 209         // Initiate the payment.
 210         let payment_id = PaymentId(payment_hash.0);
 211         let mut route_params = route.route_params.clone().unwrap();
 212
 213         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
 214         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
 215                 payment_id, route_params.clone(), Retry::Attempts(1)).unwrap();
 216         check_added_monitors!(nodes[0], 2); // one monitor per path
 217         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 218         assert_eq!(events.len(), 2);
 219
 220         // Pass half of the payment along the success path.
 221         let success_path_msgs = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 222         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], amt_msat, payment_hash,
 223                 Some(payment_secret), success_path_msgs, false, None);
 224
 225         // Add the HTLC along the first hop.
 226         let fail_path_msgs_1 = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 227         let send_event = SendEvent::from_event(fail_path_msgs_1);
 228         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
 229         commitment_signed_dance!(nodes[2], nodes[0], &send_event.commitment_msg, false);
 230
 231         // Attempt to forward the payment and complete the 2nd path's failure.
 232         expect_pending_htlcs_forwardable!(&nodes[2]);
 233         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[2],
 234                 vec![HTLCDestination::NextHopChannel {
 235                         node_id: Some(nodes[3].node.get_our_node_id()), channel_id: chan_4_id
 236                 }]
 237         );
 238         let htlc_updates = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id());
 239         assert!(htlc_updates.update_add_htlcs.is_empty());
 240         assert_eq!(htlc_updates.update_fail_htlcs.len(), 1);
 241         assert!(htlc_updates.update_fulfill_htlcs.is_empty());
 242         assert!(htlc_updates.update_fail_malformed_htlcs.is_empty());
 243         check_added_monitors!(nodes[2], 1);
 244         nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(),
 245                 &htlc_updates.update_fail_htlcs[0]);
 246         commitment_signed_dance!(nodes[0], nodes[2], htlc_updates.commitment_signed, false);
 247         let mut events = nodes[0].node.get_and_clear_pending_events();
 248         match events[1] {
 249                 Event::PendingHTLCsForwardable { .. } => {},
 250                 _ => panic!("Unexpected event")
 251         }
 252         events.remove(1);
 253         expect_payment_failed_conditions_event(events, payment_hash, false,
 254                 PaymentFailedConditions::new().mpp_parts_remain());
 255
 256         // Rebalance the channel so the second half of the payment can succeed.
 257         send_payment(&nodes[3], &vec!(&nodes[2])[..], 38_000_000);
 258
 259         // Retry the second half of the payment and make sure it succeeds.
 260         let first_path_value = route.paths[0].final_value_msat();
 261         assert_eq!(first_path_value, 36_000_000);
 262
 263         route.paths.remove(0);
 264         route_params.final_value_msat -= first_path_value;
 265         route_params.payment_params.previously_failed_channels.push(chan_4_update.contents.short_channel_id);
 266         // Check the remaining max total routing fee for the second attempt accounts only for 1_000 msat
 267         // base fee, but not for overpaid value of the first try.
 268         route_params.max_total_routing_fee_msat.as_mut().map(|m| *m -= 1000);
 269
 270         route.route_params = Some(route_params.clone());
 271         nodes[0].router.expect_find_route(route_params, Ok(route));
 272         nodes[0].node.process_pending_htlc_forwards();
 273
 274         check_added_monitors!(nodes[0], 1);
 275         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 276         assert_eq!(events.len(), 1);
 277         pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], amt_msat, payment_hash,
 278                 Some(payment_secret), events.pop().unwrap(), true, None);
 279
 280         // Can't use claim_payment_along_route as it doesn't support overpayment, so we break out the
 281         // individual steps here.
 282         nodes[3].node.claim_funds(payment_preimage);
 283         let extra_fees = vec![0, total_overpaid_amount];
 284         let expected_route = &[&[&nodes[1], &nodes[3]][..], &[&nodes[2], &nodes[3]][..]];
 285         let args = ClaimAlongRouteArgs::new(&nodes[0], &expected_route[..], payment_preimage)
 286                 .with_expected_min_htlc_overpay(extra_fees);
 287         let expected_total_fee_msat = pass_claimed_payment_along_route(args);
 288         expect_payment_sent!(&nodes[0], payment_preimage, Some(expected_total_fee_msat));
 289 }
 290
 291 fn do_mpp_receive_timeout(send_partial_mpp: bool) {
 292         let chanmon_cfgs = create_chanmon_cfgs(4);
 293         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 294         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 295         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 296
 297         let (chan_1_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 0, 1);
 298         let (chan_2_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 0, 2);
 299         let (chan_3_update, _, chan_3_id, _) = create_announced_chan_between_nodes(&nodes, 1, 3);
 300         let (chan_4_update, _, _, _) = create_announced_chan_between_nodes(&nodes, 2, 3);
 301
 302         let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[3], 100_000);
 303         let path = route.paths[0].clone();
 304         route.paths.push(path);
 305         route.paths[0].hops[0].pubkey = nodes[1].node.get_our_node_id();
 306         route.paths[0].hops[0].short_channel_id = chan_1_update.contents.short_channel_id;
 307         route.paths[0].hops[1].short_channel_id = chan_3_update.contents.short_channel_id;
 308         route.paths[1].hops[0].pubkey = nodes[2].node.get_our_node_id();
 309         route.paths[1].hops[0].short_channel_id = chan_2_update.contents.short_channel_id;
 310         route.paths[1].hops[1].short_channel_id = chan_4_update.contents.short_channel_id;
 311
 312         // Initiate the MPP payment.
 313         nodes[0].node.send_payment_with_route(&route, payment_hash,
 314                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
 315         check_added_monitors!(nodes[0], 2); // one monitor per path
 316         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 317         assert_eq!(events.len(), 2);
 318
 319         // Pass half of the payment along the first path.
 320         let node_1_msgs = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 321         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 200_000, payment_hash, Some(payment_secret), node_1_msgs, false, None);
 322
 323         if send_partial_mpp {
 324                 // Time out the partial MPP
 325                 for _ in 0..MPP_TIMEOUT_TICKS {
 326                         nodes[3].node.timer_tick_occurred();
 327                 }
 328
 329                 // Failed HTLC from node 3 -> 1
 330                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[3], vec![HTLCDestination::FailedPayment { payment_hash }]);
 331                 let htlc_fail_updates_3_1 = get_htlc_update_msgs!(nodes[3], nodes[1].node.get_our_node_id());
 332                 assert_eq!(htlc_fail_updates_3_1.update_fail_htlcs.len(), 1);
 333                 nodes[1].node.handle_update_fail_htlc(&nodes[3].node.get_our_node_id(), &htlc_fail_updates_3_1.update_fail_htlcs[0]);
 334                 check_added_monitors!(nodes[3], 1);
 335                 commitment_signed_dance!(nodes[1], nodes[3], htlc_fail_updates_3_1.commitment_signed, false);
 336
 337                 // Failed HTLC from node 1 -> 0
 338                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], vec![HTLCDestination::NextHopChannel { node_id: Some(nodes[3].node.get_our_node_id()), channel_id: chan_3_id }]);
 339                 let htlc_fail_updates_1_0 = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 340                 assert_eq!(htlc_fail_updates_1_0.update_fail_htlcs.len(), 1);
 341                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_fail_updates_1_0.update_fail_htlcs[0]);
 342                 check_added_monitors!(nodes[1], 1);
 343                 commitment_signed_dance!(nodes[0], nodes[1], htlc_fail_updates_1_0.commitment_signed, false);
 344
 345                 expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain().expected_htlc_error_data(23, &[][..]));
 346         } else {
 347                 // Pass half of the payment along the second path.
 348                 let node_2_msgs = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 349                 pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 200_000, payment_hash, Some(payment_secret), node_2_msgs, true, None);
 350
 351                 // Even after MPP_TIMEOUT_TICKS we should not timeout the MPP if we have all the parts
 352                 for _ in 0..MPP_TIMEOUT_TICKS {
 353                         nodes[3].node.timer_tick_occurred();
 354                 }
 355
 356                 claim_payment_along_route(
 357                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], payment_preimage)
 358                 );
 359         }
 360 }
 361
 362 #[test]
 363 fn mpp_receive_timeout() {
 364         do_mpp_receive_timeout(true);
 365         do_mpp_receive_timeout(false);
 366 }
 367
 368 #[test]
 369 fn test_keysend_payments() {
 370         do_test_keysend_payments(false, false);
 371         do_test_keysend_payments(false, true);
 372         do_test_keysend_payments(true, false);
 373         do_test_keysend_payments(true, true);
 374 }
 375
 376 fn do_test_keysend_payments(public_node: bool, with_retry: bool) {
 377         let chanmon_cfgs = create_chanmon_cfgs(2);
 378         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 379         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 380         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 381
 382         if public_node {
 383                 create_announced_chan_between_nodes(&nodes, 0, 1);
 384         } else {
 385                 create_chan_between_nodes(&nodes[0], &nodes[1]);
 386         }
 387         let payer_pubkey = nodes[0].node.get_our_node_id();
 388         let payee_pubkey = nodes[1].node.get_our_node_id();
 389         let route_params = RouteParameters::from_payment_params_and_value(
 390                 PaymentParameters::for_keysend(payee_pubkey, 40, false), 10000);
 391
 392         let network_graph = nodes[0].network_graph;
 393         let channels = nodes[0].node.list_usable_channels();
 394         let first_hops = channels.iter().collect::<Vec<_>>();
 395         let first_hops = if public_node { None } else { Some(first_hops.as_slice()) };
 396
 397         let scorer = test_utils::TestScorer::new();
 398         let random_seed_bytes = chanmon_cfgs[1].keys_manager.get_secure_random_bytes();
 399         let route = find_route(
 400                 &payer_pubkey, &route_params, &network_graph, first_hops,
 401                 nodes[0].logger, &scorer, &Default::default(), &random_seed_bytes
 402         ).unwrap();
 403
 404         {
 405                 let test_preimage = PaymentPreimage([42; 32]);
 406                 if with_retry {
 407                         nodes[0].node.send_spontaneous_payment_with_retry(Some(test_preimage),
 408                                 RecipientOnionFields::spontaneous_empty(), PaymentId(test_preimage.0),
 409                                 route_params, Retry::Attempts(1)).unwrap()
 410                 } else {
 411                         nodes[0].node.send_spontaneous_payment(&route, Some(test_preimage),
 412                                 RecipientOnionFields::spontaneous_empty(), PaymentId(test_preimage.0)).unwrap()
 413                 };
 414         }
 415         check_added_monitors!(nodes[0], 1);
 416         let send_event = SendEvent::from_node(&nodes[0]);
 417         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
 418         do_commitment_signed_dance(&nodes[1], &nodes[0], &send_event.commitment_msg, false, false);
 419         expect_pending_htlcs_forwardable!(nodes[1]);
 420         // Previously, a refactor caused us to stop including the payment preimage in the onion which
 421         // is sent as a part of keysend payments. Thus, to be extra careful here, we scope the preimage
 422         // above to demonstrate that we have no way to get the preimage at this point except by
 423         // extracting it from the onion nodes[1] received.
 424         let event = nodes[1].node.get_and_clear_pending_events();
 425         assert_eq!(event.len(), 1);
 426         if let Event::PaymentClaimable { purpose: PaymentPurpose::SpontaneousPayment(preimage), .. } = event[0] {
 427                 claim_payment(&nodes[0], &[&nodes[1]], preimage);
 428         } else { panic!(); }
 429 }
 430
 431 #[test]
 432 fn test_mpp_keysend() {
 433         let mut mpp_keysend_config = test_default_channel_config();
 434         mpp_keysend_config.accept_mpp_keysend = true;
 435         let chanmon_cfgs = create_chanmon_cfgs(4);
 436         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 437         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, Some(mpp_keysend_config)]);
 438         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 439
 440         create_announced_chan_between_nodes(&nodes, 0, 1);
 441         create_announced_chan_between_nodes(&nodes, 0, 2);
 442         create_announced_chan_between_nodes(&nodes, 1, 3);
 443         create_announced_chan_between_nodes(&nodes, 2, 3);
 444         let network_graph = nodes[0].network_graph;
 445
 446         let payer_pubkey = nodes[0].node.get_our_node_id();
 447         let payee_pubkey = nodes[3].node.get_our_node_id();
 448         let recv_value = 15_000_000;
 449         let route_params = RouteParameters::from_payment_params_and_value(
 450                 PaymentParameters::for_keysend(payee_pubkey, 40, true), recv_value);
 451         let scorer = test_utils::TestScorer::new();
 452         let random_seed_bytes = chanmon_cfgs[0].keys_manager.get_secure_random_bytes();
 453         let route = find_route(&payer_pubkey, &route_params, &network_graph, None, nodes[0].logger,
 454                 &scorer, &Default::default(), &random_seed_bytes).unwrap();
 455
 456         let payment_preimage = PaymentPreimage([42; 32]);
 457         let payment_secret = PaymentSecret(payment_preimage.0);
 458         let payment_hash = nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage),
 459                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_preimage.0)).unwrap();
 460         check_added_monitors!(nodes[0], 2);
 461
 462         let expected_route: &[&[&Node]] = &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]];
 463         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 464         assert_eq!(events.len(), 2);
 465
 466         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 467         pass_along_path(&nodes[0], expected_route[0], recv_value, payment_hash.clone(),
 468                 Some(payment_secret), ev.clone(), false, Some(payment_preimage));
 469
 470         let ev = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 471         pass_along_path(&nodes[0], expected_route[1], recv_value, payment_hash.clone(),
 472                 Some(payment_secret), ev.clone(), true, Some(payment_preimage));
 473         claim_payment_along_route(
 474                 ClaimAlongRouteArgs::new(&nodes[0], expected_route, payment_preimage)
 475         );
 476 }
 477
 478 #[test]
 479 fn test_reject_mpp_keysend_htlc() {
 480         // This test enforces that we reject MPP keysend HTLCs if our config states we don't support
 481         // MPP keysend. When receiving a payment, if we don't support MPP keysend we'll reject the
 482         // payment if it's keysend and has a payment secret, never reaching our payment validation
 483         // logic. To check that we enforce rejecting MPP keysends in our payment logic, here we send
 484         // keysend payments without payment secrets, then modify them by adding payment secrets in the
 485         // final node in between receiving the HTLCs and actually processing them.
 486         let mut reject_mpp_keysend_cfg = test_default_channel_config();
 487         reject_mpp_keysend_cfg.accept_mpp_keysend = false;
 488
 489         let chanmon_cfgs = create_chanmon_cfgs(4);
 490         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 491         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, Some(reject_mpp_keysend_cfg)]);
 492         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 493         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1).0.contents.short_channel_id;
 494         let chan_2_id = create_announced_chan_between_nodes(&nodes, 0, 2).0.contents.short_channel_id;
 495         let chan_3_id = create_announced_chan_between_nodes(&nodes, 1, 3).0.contents.short_channel_id;
 496         let (update_a, _, chan_4_channel_id, _) = create_announced_chan_between_nodes(&nodes, 2, 3);
 497         let chan_4_id = update_a.contents.short_channel_id;
 498         let amount = 40_000;
 499         let (mut route, payment_hash, payment_preimage, _) = get_route_and_payment_hash!(nodes[0], nodes[3], amount);
 500
 501         // Pay along nodes[1]
 502         route.paths[0].hops[0].pubkey = nodes[1].node.get_our_node_id();
 503         route.paths[0].hops[0].short_channel_id = chan_1_id;
 504         route.paths[0].hops[1].short_channel_id = chan_3_id;
 505
 506         let payment_id_0 = PaymentId(nodes[0].keys_manager.backing.get_secure_random_bytes());
 507         nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage), RecipientOnionFields::spontaneous_empty(), payment_id_0).unwrap();
 508         check_added_monitors!(nodes[0], 1);
 509
 510         let update_0 = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
 511         let update_add_0 = update_0.update_add_htlcs[0].clone();
 512         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add_0);
 513         commitment_signed_dance!(nodes[1], nodes[0], &update_0.commitment_signed, false, true);
 514         expect_pending_htlcs_forwardable!(nodes[1]);
 515
 516         check_added_monitors!(&nodes[1], 1);
 517         let update_1 = get_htlc_update_msgs!(nodes[1], nodes[3].node.get_our_node_id());
 518         let update_add_1 = update_1.update_add_htlcs[0].clone();
 519         nodes[3].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &update_add_1);
 520         commitment_signed_dance!(nodes[3], nodes[1], update_1.commitment_signed, false, true);
 521
 522         assert!(nodes[3].node.get_and_clear_pending_msg_events().is_empty());
 523         for (_, pending_forwards) in nodes[3].node.forward_htlcs.lock().unwrap().iter_mut() {
 524                 for f in pending_forwards.iter_mut() {
 525                         match f {
 526                                 &mut HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo { ref mut forward_info, .. }) => {
 527                                         match forward_info.routing {
 528                                                 PendingHTLCRouting::ReceiveKeysend { ref mut payment_data, .. } => {
 529                                                         *payment_data = Some(msgs::FinalOnionHopData {
 530                                                                 payment_secret: PaymentSecret([42; 32]),
 531                                                                 total_msat: amount * 2,
 532                                                         });
 533                                                 },
 534                                                 _ => panic!("Expected PendingHTLCRouting::ReceiveKeysend"),
 535                                         }
 536                                 },
 537                                 _ => {},
 538                         }
 539                 }
 540         }
 541         expect_pending_htlcs_forwardable!(nodes[3]);
 542
 543         // Pay along nodes[2]
 544         route.paths[0].hops[0].pubkey = nodes[2].node.get_our_node_id();
 545         route.paths[0].hops[0].short_channel_id = chan_2_id;
 546         route.paths[0].hops[1].short_channel_id = chan_4_id;
 547
 548         let payment_id_1 = PaymentId(nodes[0].keys_manager.backing.get_secure_random_bytes());
 549         nodes[0].node.send_spontaneous_payment(&route, Some(payment_preimage), RecipientOnionFields::spontaneous_empty(), payment_id_1).unwrap();
 550         check_added_monitors!(nodes[0], 1);
 551
 552         let update_2 = get_htlc_update_msgs!(nodes[0], nodes[2].node.get_our_node_id());
 553         let update_add_2 = update_2.update_add_htlcs[0].clone();
 554         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add_2);
 555         commitment_signed_dance!(nodes[2], nodes[0], &update_2.commitment_signed, false, true);
 556         expect_pending_htlcs_forwardable!(nodes[2]);
 557
 558         check_added_monitors!(&nodes[2], 1);
 559         let update_3 = get_htlc_update_msgs!(nodes[2], nodes[3].node.get_our_node_id());
 560         let update_add_3 = update_3.update_add_htlcs[0].clone();
 561         nodes[3].node.handle_update_add_htlc(&nodes[2].node.get_our_node_id(), &update_add_3);
 562         commitment_signed_dance!(nodes[3], nodes[2], update_3.commitment_signed, false, true);
 563
 564         assert!(nodes[3].node.get_and_clear_pending_msg_events().is_empty());
 565         for (_, pending_forwards) in nodes[3].node.forward_htlcs.lock().unwrap().iter_mut() {
 566                 for f in pending_forwards.iter_mut() {
 567                         match f {
 568                                 &mut HTLCForwardInfo::AddHTLC(PendingAddHTLCInfo { ref mut forward_info, .. }) => {
 569                                         match forward_info.routing {
 570                                                 PendingHTLCRouting::ReceiveKeysend { ref mut payment_data, .. } => {
 571                                                         *payment_data = Some(msgs::FinalOnionHopData {
 572                                                                 payment_secret: PaymentSecret([42; 32]),
 573                                                                 total_msat: amount * 2,
 574                                                         });
 575                                                 },
 576                                                 _ => panic!("Expected PendingHTLCRouting::ReceiveKeysend"),
 577                                         }
 578                                 },
 579                                 _ => {},
 580                         }
 581                 }
 582         }
 583         expect_pending_htlcs_forwardable!(nodes[3]);
 584         check_added_monitors!(nodes[3], 1);
 585
 586         // Fail back along nodes[2]
 587         let update_fail_0 = get_htlc_update_msgs!(&nodes[3], &nodes[2].node.get_our_node_id());
 588         nodes[2].node.handle_update_fail_htlc(&nodes[3].node.get_our_node_id(), &update_fail_0.update_fail_htlcs[0]);
 589         commitment_signed_dance!(nodes[2], nodes[3], update_fail_0.commitment_signed, false);
 590         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[2], vec![HTLCDestination::NextHopChannel { node_id: Some(nodes[3].node.get_our_node_id()), channel_id: chan_4_channel_id }]);
 591         check_added_monitors!(nodes[2], 1);
 592
 593         let update_fail_1 = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id());
 594         nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &update_fail_1.update_fail_htlcs[0]);
 595         commitment_signed_dance!(nodes[0], nodes[2], update_fail_1.commitment_signed, false);
 596
 597         expect_payment_failed_conditions(&nodes[0], payment_hash, true, PaymentFailedConditions::new());
 598         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[3], vec![HTLCDestination::FailedPayment { payment_hash }]);
 599 }
 600
 601
 602 #[test]
 603 fn no_pending_leak_on_initial_send_failure() {
 604         // In an earlier version of our payment tracking, we'd have a retry entry even when the initial
 605         // HTLC for payment failed to send due to local channel errors (e.g. peer disconnected). In this
 606         // case, the user wouldn't have a PaymentId to retry the payment with, but we'd think we have a
 607         // pending payment forever and never time it out.
 608         // Here we test exactly that - retrying a payment when a peer was disconnected on the first
 609         // try, and then check that no pending payment is being tracked.
 610         let chanmon_cfgs = create_chanmon_cfgs(2);
 611         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 612         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 613         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 614
 615         create_announced_chan_between_nodes(&nodes, 0, 1);
 616
 617         let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
 618
 619         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
 620         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
 621
 622         unwrap_send_err!(nodes[0].node.send_payment_with_route(&route, payment_hash,
 623                         RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
 624                 ), true, APIError::ChannelUnavailable { ref err },
 625                 assert_eq!(err, "Peer for first hop currently disconnected"));
 626
 627         assert!(!nodes[0].node.has_pending_payments());
 628 }
 629
 630 fn do_retry_with_no_persist(confirm_before_reload: bool) {
 631         // If we send a pending payment and `send_payment` returns success, we should always either
 632         // return a payment failure event or a payment success event, and on failure the payment should
 633         // be retryable.
 634         //
 635         // In order to do so when the ChannelManager isn't immediately persisted (which is normal - its
 636         // always persisted asynchronously), the ChannelManager has to reload some payment data from
 637         // ChannelMonitor(s) in some cases. This tests that reloading.
 638         //
 639         // `confirm_before_reload` confirms the channel-closing commitment transaction on-chain prior
 640         // to reloading the ChannelManager, increasing test coverage in ChannelMonitor HTLC tracking
 641         // which has separate codepaths for "commitment transaction already confirmed" and not.
 642         let chanmon_cfgs = create_chanmon_cfgs(3);
 643         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 644         let persister;
 645         let new_chain_monitor;
 646         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 647         let nodes_0_deserialized;
 648         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 649
 650         let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
 651         let (_, _, chan_id_2, _) = create_announced_chan_between_nodes(&nodes, 1, 2);
 652
 653         // Serialize the ChannelManager prior to sending payments
 654         let nodes_0_serialized = nodes[0].node.encode();
 655
 656         // Send two payments - one which will get to nodes[2] and will be claimed, one which we'll time
 657         // out and retry.
 658         let amt_msat = 1_000_000;
 659         let (route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
 660         let (payment_preimage_1, payment_hash_1, _, payment_id_1) = send_along_route(&nodes[0], route.clone(), &[&nodes[1], &nodes[2]], 1_000_000);
 661         let route_params = route.route_params.unwrap().clone();
 662         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
 663                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
 664         check_added_monitors!(nodes[0], 1);
 665
 666         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 667         assert_eq!(events.len(), 1);
 668         let payment_event = SendEvent::from_event(events.pop().unwrap());
 669         assert_eq!(payment_event.node_id, nodes[1].node.get_our_node_id());
 670
 671         // We relay the payment to nodes[1] while its disconnected from nodes[2], causing the payment
 672         // to be returned immediately to nodes[0], without having nodes[2] fail the inbound payment
 673         // which would prevent retry.
 674         nodes[1].node.peer_disconnected(&nodes[2].node.get_our_node_id());
 675         nodes[2].node.peer_disconnected(&nodes[1].node.get_our_node_id());
 676
 677         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 678         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false, true);
 679         // nodes[1] now immediately fails the HTLC as the next-hop channel is disconnected
 680         let _ = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 681
 682         reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[2]));
 683
 684         let as_commitment_tx = get_local_commitment_txn!(nodes[0], chan_id)[0].clone();
 685         if confirm_before_reload {
 686                 mine_transaction(&nodes[0], &as_commitment_tx);
 687                 nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 688         }
 689
 690         // The ChannelMonitor should always be the latest version, as we're required to persist it
 691         // during the `commitment_signed_dance!()`.
 692         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
 693         reload_node!(nodes[0], test_default_channel_config(), &nodes_0_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);
 694
 695         // On reload, the ChannelManager should realize it is stale compared to the ChannelMonitor and
 696         // force-close the channel.
 697         check_closed_event!(nodes[0], 1, ClosureReason::OutdatedChannelManager, [nodes[1].node.get_our_node_id()], 100000);
 698         assert!(nodes[0].node.list_channels().is_empty());
 699         assert!(nodes[0].node.has_pending_payments());
 700         nodes[0].node.timer_tick_occurred();
 701         if !confirm_before_reload {
 702                 let as_broadcasted_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 703                 assert_eq!(as_broadcasted_txn.len(), 1);
 704                 assert_eq!(as_broadcasted_txn[0].txid(), as_commitment_tx.txid());
 705         } else {
 706                 assert!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().is_empty());
 707         }
 708         check_added_monitors!(nodes[0], 1);
 709
 710         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
 711         nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
 712                 features: nodes[1].node.init_features(), networks: None, remote_network_address: None
 713         }, true).unwrap();
 714         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 715
 716         // Now nodes[1] should send a channel reestablish, which nodes[0] will respond to with an
 717         // error, as the channel has hit the chain.
 718         nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
 719                 features: nodes[0].node.init_features(), networks: None, remote_network_address: None
 720         }, false).unwrap();
 721         let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 722         nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 723         let as_err = nodes[0].node.get_and_clear_pending_msg_events();
 724         assert_eq!(as_err.len(), 2);
 725         match as_err[1] {
 726                 MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
 727                         assert_eq!(node_id, nodes[1].node.get_our_node_id());
 728                         nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
 729                         check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: UntrustedString(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}",
 730                                 &nodes[1].node.get_our_node_id())) }, [nodes[0].node.get_our_node_id()], 100000);
 731                         check_added_monitors!(nodes[1], 1);
 732                         assert_eq!(nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0).len(), 1);
 733                 },
 734                 _ => panic!("Unexpected event"),
 735         }
 736         check_closed_broadcast!(nodes[1], false);
 737
 738         // Now claim the first payment, which should allow nodes[1] to claim the payment on-chain when
 739         // we close in a moment.
 740         nodes[2].node.claim_funds(payment_preimage_1);
 741         check_added_monitors!(nodes[2], 1);
 742         expect_payment_claimed!(nodes[2], payment_hash_1, 1_000_000);
 743
 744         let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[2], nodes[1].node.get_our_node_id());
 745         nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
 746         check_added_monitors!(nodes[1], 1);
 747         commitment_signed_dance!(nodes[1], nodes[2], htlc_fulfill_updates.commitment_signed, false);
 748         expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], None, true, false);
 749
 750         if confirm_before_reload {
 751                 let best_block = nodes[0].blocks.lock().unwrap().last().unwrap().clone();
 752                 nodes[0].node.best_block_updated(&best_block.0.header, best_block.1);
 753         }
 754
 755         // Create a new channel on which to retry the payment before we fail the payment via the
 756         // HTLC-Timeout transaction. This avoids ChannelManager timing out the payment due to us
 757         // connecting several blocks while creating the channel (implying time has passed).
 758         create_announced_chan_between_nodes(&nodes, 0, 1);
 759         assert_eq!(nodes[0].node.list_usable_channels().len(), 1);
 760
 761         mine_transaction(&nodes[1], &as_commitment_tx);
 762         let bs_htlc_claim_txn = {
 763                 let mut txn = nodes[1].tx_broadcaster.unique_txn_broadcast();
 764                 assert_eq!(txn.len(), 2);
 765                 check_spends!(txn[0], funding_tx);
 766                 check_spends!(txn[1], as_commitment_tx);
 767                 txn.pop().unwrap()
 768         };
 769
 770         if !confirm_before_reload {
 771                 mine_transaction(&nodes[0], &as_commitment_tx);
 772                 let txn = nodes[0].tx_broadcaster.unique_txn_broadcast();
 773                 assert_eq!(txn.len(), 1);
 774                 assert_eq!(txn[0].txid(), as_commitment_tx.txid());
 775         }
 776         mine_transaction(&nodes[0], &bs_htlc_claim_txn);
 777         expect_payment_sent(&nodes[0], payment_preimage_1, None, true, false);
 778         connect_blocks(&nodes[0], TEST_FINAL_CLTV*4 + 20);
 779         let (first_htlc_timeout_tx, second_htlc_timeout_tx) = {
 780                 let mut txn = nodes[0].tx_broadcaster.unique_txn_broadcast();
 781                 assert_eq!(txn.len(), 2);
 782                 (txn.remove(0), txn.remove(0))
 783         };
 784         check_spends!(first_htlc_timeout_tx, as_commitment_tx);
 785         check_spends!(second_htlc_timeout_tx, as_commitment_tx);
 786         if first_htlc_timeout_tx.input[0].previous_output == bs_htlc_claim_txn.input[0].previous_output {
 787                 confirm_transaction(&nodes[0], &second_htlc_timeout_tx);
 788         } else {
 789                 confirm_transaction(&nodes[0], &first_htlc_timeout_tx);
 790         }
 791         nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 792         expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new());
 793
 794         // Finally, retry the payment (which was reloaded from the ChannelMonitor when nodes[0] was
 795         // reloaded) via a route over the new channel, which work without issue and eventually be
 796         // received and claimed at the recipient just like any other payment.
 797         let (mut new_route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
 798
 799         // Update the fee on the middle hop to ensure PaymentSent events have the correct (retried) fee
 800         // and not the original fee. We also update node[1]'s relevant config as
 801         // do_claim_payment_along_route expects us to never overpay.
 802         {
 803                 let per_peer_state = nodes[1].node.per_peer_state.read().unwrap();
 804                 let mut peer_state = per_peer_state.get(&nodes[2].node.get_our_node_id())
 805                         .unwrap().lock().unwrap();
 806                 let mut channel = peer_state.channel_by_id.get_mut(&chan_id_2).unwrap();
 807                 let mut new_config = channel.context().config();
 808                 new_config.forwarding_fee_base_msat += 100_000;
 809                 channel.context_mut().update_config(&new_config);
 810                 new_route.paths[0].hops[0].fee_msat += 100_000;
 811         }
 812
 813         // Force expiration of the channel's previous config.
 814         for _ in 0..EXPIRE_PREV_CONFIG_TICKS {
 815                 nodes[1].node.timer_tick_occurred();
 816         }
 817
 818         assert!(nodes[0].node.send_payment_with_route(&new_route, payment_hash, // Shouldn't be allowed to retry a fulfilled payment
 819                 RecipientOnionFields::secret_only(payment_secret), payment_id_1).is_err());
 820         nodes[0].node.send_payment_with_route(&new_route, payment_hash,
 821                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
 822         check_added_monitors!(nodes[0], 1);
 823         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 824         assert_eq!(events.len(), 1);
 825         pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000, payment_hash, Some(payment_secret), events.pop().unwrap(), true, None);
 826         do_claim_payment_along_route(
 827                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
 828         );
 829         expect_payment_sent!(nodes[0], payment_preimage, Some(new_route.paths[0].hops[0].fee_msat));
 830 }
 831
 832 #[test]
 833 fn retry_with_no_persist() {
 834         do_retry_with_no_persist(true);
 835         do_retry_with_no_persist(false);
 836 }
 837
 838 fn do_test_completed_payment_not_retryable_on_reload(use_dust: bool) {
 839         // Test that an off-chain completed payment is not retryable on restart. This was previously
 840         // broken for dust payments, but we test for both dust and non-dust payments.
 841         //
 842         // `use_dust` switches to using a dust HTLC, which results in the HTLC not having an on-chain
 843         // output at all.
 844         let chanmon_cfgs = create_chanmon_cfgs(3);
 845         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 846
 847         let mut manually_accept_config = test_default_channel_config();
 848         manually_accept_config.manually_accept_inbound_channels = true;
 849
 850         let first_persister;
 851         let first_new_chain_monitor;
 852         let second_persister;
 853         let second_new_chain_monitor;
 854         let third_persister;
 855         let third_new_chain_monitor;
 856
 857         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(manually_accept_config), None]);
 858         let first_nodes_0_deserialized;
 859         let second_nodes_0_deserialized;
 860         let third_nodes_0_deserialized;
 861
 862         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 863
 864         // Because we set nodes[1] to manually accept channels, just open a 0-conf channel.
 865         let (funding_tx, chan_id) = open_zero_conf_channel(&nodes[0], &nodes[1], None);
 866         confirm_transaction(&nodes[0], &funding_tx);
 867         confirm_transaction(&nodes[1], &funding_tx);
 868         // Ignore the announcement_signatures messages
 869         nodes[0].node.get_and_clear_pending_msg_events();
 870         nodes[1].node.get_and_clear_pending_msg_events();
 871         let chan_id_2 = create_announced_chan_between_nodes(&nodes, 1, 2).2;
 872
 873         // Serialize the ChannelManager prior to sending payments
 874         let mut nodes_0_serialized = nodes[0].node.encode();
 875
 876         let route = get_route_and_payment_hash!(nodes[0], nodes[2], if use_dust { 1_000 } else { 1_000_000 }).0;
 877         let (payment_preimage, payment_hash, payment_secret, payment_id) = send_along_route(&nodes[0], route, &[&nodes[1], &nodes[2]], if use_dust { 1_000 } else { 1_000_000 });
 878
 879         // The ChannelMonitor should always be the latest version, as we're required to persist it
 880         // during the `commitment_signed_dance!()`.
 881         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
 882
 883         reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized], first_persister, first_new_chain_monitor, first_nodes_0_deserialized);
 884         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
 885
 886         // On reload, the ChannelManager should realize it is stale compared to the ChannelMonitor and
 887         // force-close the channel.
 888         check_closed_event!(nodes[0], 1, ClosureReason::OutdatedChannelManager, [nodes[1].node.get_our_node_id()], 100000);
 889         nodes[0].node.timer_tick_occurred();
 890         assert!(nodes[0].node.list_channels().is_empty());
 891         assert!(nodes[0].node.has_pending_payments());
 892         assert_eq!(nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0).len(), 1);
 893         check_added_monitors!(nodes[0], 1);
 894
 895         nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init {
 896                 features: nodes[1].node.init_features(), networks: None, remote_network_address: None
 897         }, true).unwrap();
 898         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 899
 900         // Now nodes[1] should send a channel reestablish, which nodes[0] will respond to with an
 901         // error, as the channel has hit the chain.
 902         nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init {
 903                 features: nodes[0].node.init_features(), networks: None, remote_network_address: None
 904         }, false).unwrap();
 905         let bs_reestablish = get_chan_reestablish_msgs!(nodes[1], nodes[0]).pop().unwrap();
 906         nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 907         let as_err = nodes[0].node.get_and_clear_pending_msg_events();
 908         assert_eq!(as_err.len(), 2);
 909         let bs_commitment_tx;
 910         match as_err[1] {
 911                 MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
 912                         assert_eq!(node_id, nodes[1].node.get_our_node_id());
 913                         nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
 914                         check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: UntrustedString(format!("Got a message for a channel from the wrong node! No such channel for the passed counterparty_node_id {}", &nodes[1].node.get_our_node_id())) }
 915                                 , [nodes[0].node.get_our_node_id()], 100000);
 916                         check_added_monitors!(nodes[1], 1);
 917                         bs_commitment_tx = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 918                 },
 919                 _ => panic!("Unexpected event"),
 920         }
 921         check_closed_broadcast!(nodes[1], false);
 922
 923         // Now fail back the payment from nodes[2] to nodes[1]. This doesn't really matter as the
 924         // previous hop channel is already on-chain, but it makes nodes[2] willing to see additional
 925         // incoming HTLCs with the same payment hash later.
 926         nodes[2].node.fail_htlc_backwards(&payment_hash);
 927         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[2], [HTLCDestination::FailedPayment { payment_hash }]);
 928         check_added_monitors!(nodes[2], 1);
 929
 930         let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[2], nodes[1].node.get_our_node_id());
 931         nodes[1].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &htlc_fulfill_updates.update_fail_htlcs[0]);
 932         commitment_signed_dance!(nodes[1], nodes[2], htlc_fulfill_updates.commitment_signed, false);
 933         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1],
 934                 [HTLCDestination::NextHopChannel { node_id: Some(nodes[2].node.get_our_node_id()), channel_id: chan_id_2 }]);
 935
 936         // Connect the HTLC-Timeout transaction, timing out the HTLC on both nodes (but not confirming
 937         // the HTLC-Timeout transaction beyond 1 conf). For dust HTLCs, the HTLC is considered resolved
 938         // after the commitment transaction, so always connect the commitment transaction.
 939         mine_transaction(&nodes[0], &bs_commitment_tx[0]);
 940         if nodes[0].connect_style.borrow().updates_best_block_first() {
 941                 let _ = nodes[0].tx_broadcaster.txn_broadcast();
 942         }
 943         mine_transaction(&nodes[1], &bs_commitment_tx[0]);
 944         if !use_dust {
 945                 connect_blocks(&nodes[0], TEST_FINAL_CLTV + (MIN_CLTV_EXPIRY_DELTA as u32));
 946                 connect_blocks(&nodes[1], TEST_FINAL_CLTV + (MIN_CLTV_EXPIRY_DELTA as u32));
 947                 let as_htlc_timeout = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 948                 assert_eq!(as_htlc_timeout.len(), 1);
 949                 check_spends!(as_htlc_timeout[0], bs_commitment_tx[0]);
 950
 951                 mine_transaction(&nodes[0], &as_htlc_timeout[0]);
 952                 mine_transaction(&nodes[1], &as_htlc_timeout[0]);
 953         }
 954         if nodes[0].connect_style.borrow().updates_best_block_first() {
 955                 let _ = nodes[0].tx_broadcaster.txn_broadcast();
 956         }
 957
 958         // Create a new channel on which to retry the payment before we fail the payment via the
 959         // HTLC-Timeout transaction. This avoids ChannelManager timing out the payment due to us
 960         // connecting several blocks while creating the channel (implying time has passed).
 961         // We do this with a zero-conf channel to avoid connecting blocks as a side-effect.
 962         let (_, chan_id_3) = open_zero_conf_channel(&nodes[0], &nodes[1], None);
 963         assert_eq!(nodes[0].node.list_usable_channels().len(), 1);
 964
 965         // If we attempt to retry prior to the HTLC-Timeout (or commitment transaction, for dust HTLCs)
 966         // confirming, we will fail as it's considered still-pending...
 967         let (new_route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[2], if use_dust { 1_000 } else { 1_000_000 });
 968         match nodes[0].node.send_payment_with_route(&new_route, payment_hash, RecipientOnionFields::secret_only(payment_secret), payment_id) {
 969                 Err(PaymentSendFailure::DuplicatePayment) => {},
 970                 _ => panic!("Unexpected error")
 971         }
 972         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 973
 974         // After ANTI_REORG_DELAY confirmations, the HTLC should be failed and we can try the payment
 975         // again. We serialize the node first as we'll then test retrying the HTLC after a restart
 976         // (which should also still work).
 977         connect_blocks(&nodes[0], ANTI_REORG_DELAY - 1);
 978         connect_blocks(&nodes[1], ANTI_REORG_DELAY - 1);
 979         expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new());
 980
 981         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
 982         let chan_1_monitor_serialized = get_monitor!(nodes[0], chan_id_3).encode();
 983         nodes_0_serialized = nodes[0].node.encode();
 984
 985         // After the payment failed, we're free to send it again.
 986         assert!(nodes[0].node.send_payment_with_route(&new_route, payment_hash,
 987                 RecipientOnionFields::secret_only(payment_secret), payment_id).is_ok());
 988         assert!(!nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 989
 990         reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], second_persister, second_new_chain_monitor, second_nodes_0_deserialized);
 991         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
 992
 993         nodes[0].node.test_process_background_events();
 994         check_added_monitors(&nodes[0], 1);
 995
 996         let mut reconnect_args = ReconnectArgs::new(&nodes[0], &nodes[1]);
 997         reconnect_args.send_channel_ready = (true, true);
 998         reconnect_nodes(reconnect_args);
 999
1000         // Now resend the payment, delivering the HTLC and actually claiming it this time. This ensures
1001         // the payment is not (spuriously) listed as still pending.
1002         assert!(nodes[0].node.send_payment_with_route(&new_route, payment_hash,
1003                 RecipientOnionFields::secret_only(payment_secret), payment_id).is_ok());
1004         check_added_monitors!(nodes[0], 1);
1005         pass_along_route(&nodes[0], &[&[&nodes[1], &nodes[2]]], if use_dust { 1_000 } else { 1_000_000 }, payment_hash, payment_secret);
1006         claim_payment(&nodes[0], &[&nodes[1], &nodes[2]], payment_preimage);
1007
1008         match nodes[0].node.send_payment_with_route(&new_route, payment_hash, RecipientOnionFields::secret_only(payment_secret), payment_id) {
1009                 Err(PaymentSendFailure::DuplicatePayment) => {},
1010                 _ => panic!("Unexpected error")
1011         }
1012         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
1013
1014         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
1015         let chan_1_monitor_serialized = get_monitor!(nodes[0], chan_id_3).encode();
1016         nodes_0_serialized = nodes[0].node.encode();
1017
1018         // Check that after reload we can send the payment again (though we shouldn't, since it was
1019         // claimed previously).
1020         reload_node!(nodes[0], test_default_channel_config(), nodes_0_serialized, &[&chan_0_monitor_serialized, &chan_1_monitor_serialized], third_persister, third_new_chain_monitor, third_nodes_0_deserialized);
1021         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
1022
1023         nodes[0].node.test_process_background_events();
1024         check_added_monitors(&nodes[0], 1);
1025
1026         reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
1027
1028         match nodes[0].node.send_payment_with_route(&new_route, payment_hash, RecipientOnionFields::secret_only(payment_secret), payment_id) {
1029                 Err(PaymentSendFailure::DuplicatePayment) => {},
1030                 _ => panic!("Unexpected error")
1031         }
1032         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
1033 }
1034
1035 #[test]
1036 fn test_completed_payment_not_retryable_on_reload() {
1037         do_test_completed_payment_not_retryable_on_reload(true);
1038         do_test_completed_payment_not_retryable_on_reload(false);
1039 }
1040
1041 fn do_test_dup_htlc_onchain_doesnt_fail_on_reload(persist_manager_post_event: bool, confirm_commitment_tx: bool, payment_timeout: bool) {
1042         // When a Channel is closed, any outbound HTLCs which were relayed through it are simply
1043         // dropped. From there, the ChannelManager relies on the ChannelMonitor having a copy of the
1044         // relevant fail-/claim-back data and processes the HTLC fail/claim when the ChannelMonitor tells
1045         // it to.
1046         //
1047         // If, due to an on-chain event, an HTLC is failed/claimed, we provide the
1048         // ChannelManager with the HTLC event without waiting for ChannelMonitor persistence.
1049         // This might generate duplicate HTLC fail/claim (e.g. via a PaymentPathFailed event) on reload.
1050         let chanmon_cfgs = create_chanmon_cfgs(2);
1051         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1052         let persister;
1053         let new_chain_monitor;
1054         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1055         let nodes_0_deserialized;
1056         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1057
1058         let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
1059         let error_message = "Channel force-closed";
1060
1061         // Route a payment, but force-close the channel before the HTLC fulfill message arrives at
1062         // nodes[0].
1063         let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 10_000_000);
1064         nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
1065         check_closed_broadcast!(nodes[0], true);
1066         check_added_monitors!(nodes[0], 1);
1067         check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) }, [nodes[1].node.get_our_node_id()], 100000);
1068
1069         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
1070         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id());
1071
1072         // Connect blocks until the CLTV timeout is up so that we get an HTLC-Timeout transaction
1073         connect_blocks(&nodes[0], TEST_FINAL_CLTV + LATENCY_GRACE_PERIOD_BLOCKS + 1);
1074         let (commitment_tx, htlc_timeout_tx) = {
1075                 let mut txn = nodes[0].tx_broadcaster.unique_txn_broadcast();
1076                 assert_eq!(txn.len(), 2);
1077                 check_spends!(txn[0], funding_tx);
1078                 check_spends!(txn[1], txn[0]);
1079                 (txn.remove(0), txn.remove(0))
1080         };
1081
1082         nodes[1].node.claim_funds(payment_preimage);
1083         check_added_monitors!(nodes[1], 1);
1084         expect_payment_claimed!(nodes[1], payment_hash, 10_000_000);
1085
1086         mine_transaction(&nodes[1], &commitment_tx);
1087         check_closed_broadcast!(nodes[1], true);
1088         check_added_monitors!(nodes[1], 1);
1089         check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed, [nodes[0].node.get_our_node_id()], 100000);
1090         let htlc_success_tx = {
1091                 let mut txn = nodes[1].tx_broadcaster.txn_broadcast();
1092                 assert_eq!(txn.len(), 1);
1093                 check_spends!(txn[0], commitment_tx);
1094                 txn.pop().unwrap()
1095         };
1096
1097         mine_transaction(&nodes[0], &commitment_tx);
1098
1099         if confirm_commitment_tx {
1100                 connect_blocks(&nodes[0], BREAKDOWN_TIMEOUT as u32 - 1);
1101         }
1102
1103         let claim_block = create_dummy_block(nodes[0].best_block_hash(), 42, if payment_timeout { vec![htlc_timeout_tx] } else { vec![htlc_success_tx] });
1104
1105         if payment_timeout {
1106                 assert!(confirm_commitment_tx); // Otherwise we're spending below our CSV!
1107                 connect_block(&nodes[0], &claim_block);
1108                 connect_blocks(&nodes[0], ANTI_REORG_DELAY - 2);
1109         }
1110
1111         // Now connect the HTLC claim transaction with the ChainMonitor-generated ChannelMonitor update
1112         // returning InProgress. This should cause the claim event to never make its way to the
1113         // ChannelManager.
1114         chanmon_cfgs[0].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
1115
1116         if payment_timeout {
1117                 connect_blocks(&nodes[0], 1);
1118         } else {
1119                 connect_block(&nodes[0], &claim_block);
1120         }
1121
1122         // Note that we skip persisting ChannelMonitors. We should still be generating the payment sent
1123         // event without ChannelMonitor persistence. If we reset to a previous state on reload, the block
1124         // should be replayed and we'll regenerate the event.
1125
1126         // If we persist the ChannelManager here, we should get the PaymentSent event after
1127         // deserialization.
1128         let mut chan_manager_serialized = Vec::new();
1129         if !persist_manager_post_event {
1130                 chan_manager_serialized = nodes[0].node.encode();
1131         }
1132
1133         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
1134         if payment_timeout {
1135                 expect_payment_failed!(nodes[0], payment_hash, false);
1136         } else {
1137                 expect_payment_sent(&nodes[0], payment_preimage, None, true, false);
1138         }
1139
1140         // If we persist the ChannelManager after we get the PaymentSent event, we shouldn't get it
1141         // twice.
1142         if persist_manager_post_event {
1143                 chan_manager_serialized = nodes[0].node.encode();
1144         }
1145
1146         // Now reload nodes[0]...
1147         reload_node!(nodes[0], &chan_manager_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_0_deserialized);
1148
1149         if persist_manager_post_event {
1150                 assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
1151         } else if payment_timeout {
1152                 expect_payment_failed!(nodes[0], payment_hash, false);
1153         } else {
1154                 expect_payment_sent(&nodes[0], payment_preimage, None, true, false);
1155         }
1156
1157         // Note that if we re-connect the block which exposed nodes[0] to the payment preimage (but
1158         // which the current ChannelMonitor has not seen), the ChannelManager's de-duplication of
1159         // payment events should kick in, leaving us with no pending events here.
1160         let height = nodes[0].blocks.lock().unwrap().len() as u32 - 1;
1161         nodes[0].chain_monitor.chain_monitor.block_connected(&claim_block, height);
1162         assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
1163         check_added_monitors(&nodes[0], 1);
1164 }
1165
1166 #[test]
1167 fn test_dup_htlc_onchain_doesnt_fail_on_reload() {
1168         do_test_dup_htlc_onchain_doesnt_fail_on_reload(true, true, true);
1169         do_test_dup_htlc_onchain_doesnt_fail_on_reload(true, true, false);
1170         do_test_dup_htlc_onchain_doesnt_fail_on_reload(true, false, false);
1171         do_test_dup_htlc_onchain_doesnt_fail_on_reload(false, true, true);
1172         do_test_dup_htlc_onchain_doesnt_fail_on_reload(false, true, false);
1173         do_test_dup_htlc_onchain_doesnt_fail_on_reload(false, false, false);
1174 }
1175
1176 #[test]
1177 fn test_fulfill_restart_failure() {
1178         // When we receive an update_fulfill_htlc message, we immediately consider the HTLC fully
1179         // fulfilled. At this point, the peer can reconnect and decide to either fulfill the HTLC
1180         // again, or fail it, giving us free money.
1181         //
1182         // Of course probably they won't fail it and give us free money, but because we have code to
1183         // handle it, we should test the logic for it anyway. We do that here.
1184         let chanmon_cfgs = create_chanmon_cfgs(2);
1185         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1186         let persister;
1187         let new_chain_monitor;
1188         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1189         let nodes_1_deserialized;
1190         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1191
1192         let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;
1193         let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 100_000);
1194
1195         // The simplest way to get a failure after a fulfill is to reload nodes[1] from a state
1196         // pre-fulfill, which we do by serializing it here.
1197         let chan_manager_serialized = nodes[1].node.encode();
1198         let chan_0_monitor_serialized = get_monitor!(nodes[1], chan_id).encode();
1199
1200         nodes[1].node.claim_funds(payment_preimage);
1201         check_added_monitors!(nodes[1], 1);
1202         expect_payment_claimed!(nodes[1], payment_hash, 100_000);
1203
1204         let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
1205         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
1206         expect_payment_sent(&nodes[0], payment_preimage, None, false, false);
1207
1208         // Now reload nodes[1]...
1209         reload_node!(nodes[1], &chan_manager_serialized, &[&chan_0_monitor_serialized], persister, new_chain_monitor, nodes_1_deserialized);
1210
1211         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id());
1212         reconnect_nodes(ReconnectArgs::new(&nodes[0], &nodes[1]));
1213
1214         nodes[1].node.fail_htlc_backwards(&payment_hash);
1215         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], vec![HTLCDestination::FailedPayment { payment_hash }]);
1216         check_added_monitors!(nodes[1], 1);
1217         let htlc_fail_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
1218         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_fail_updates.update_fail_htlcs[0]);
1219         commitment_signed_dance!(nodes[0], nodes[1], htlc_fail_updates.commitment_signed, false);
1220         // nodes[0] shouldn't generate any events here, while it just got a payment failure completion
1221         // it had already considered the payment fulfilled, and now they just got free money.
1222         assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
1223 }
1224
1225 #[test]
1226 fn get_ldk_payment_preimage() {
1227         // Ensure that `ChannelManager::get_payment_preimage` can successfully be used to claim a payment.
1228         let chanmon_cfgs = create_chanmon_cfgs(2);
1229         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1230         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1231         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1232         create_announced_chan_between_nodes(&nodes, 0, 1);
1233
1234         let amt_msat = 60_000;
1235         let expiry_secs = 60 * 60;
1236         let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(amt_msat), expiry_secs, None).unwrap();
1237
1238         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
1239                 .with_bolt11_features(nodes[1].node.bolt11_invoice_features()).unwrap();
1240         let scorer = test_utils::TestScorer::new();
1241         let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
1242         let random_seed_bytes = keys_manager.get_secure_random_bytes();
1243         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
1244         let route = get_route( &nodes[0].node.get_our_node_id(), &route_params,
1245                 &nodes[0].network_graph.read_only(),
1246                 Some(&nodes[0].node.list_usable_channels().iter().collect::<Vec<_>>()), nodes[0].logger,
1247                 &scorer, &Default::default(), &random_seed_bytes).unwrap();
1248         nodes[0].node.send_payment_with_route(&route, payment_hash,
1249                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
1250         check_added_monitors!(nodes[0], 1);
1251
1252         // Make sure to use `get_payment_preimage`
1253         let payment_preimage = nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
1254         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
1255         assert_eq!(events.len(), 1);
1256         pass_along_path(&nodes[0], &[&nodes[1]], amt_msat, payment_hash, Some(payment_secret), events.pop().unwrap(), true, Some(payment_preimage));
1257         claim_payment_along_route(
1258                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1]]], payment_preimage)
1259         );
1260 }
1261
1262 #[test]
1263 fn sent_probe_is_probe_of_sending_node() {
1264         let chanmon_cfgs = create_chanmon_cfgs(3);
1265         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1266         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None, None]);
1267         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1268
1269         create_announced_chan_between_nodes(&nodes, 0, 1);
1270         create_announced_chan_between_nodes(&nodes, 1, 2);
1271
1272         // First check we refuse to build a single-hop probe
1273         let (route, _, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[1], 100_000);
1274         assert!(nodes[0].node.send_probe(route.paths[0].clone()).is_err());
1275
1276         // Then build an actual two-hop probing path
1277         let (route, _, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[2], 100_000);
1278
1279         match nodes[0].node.send_probe(route.paths[0].clone()) {
1280                 Ok((payment_hash, payment_id)) => {
1281                         assert!(nodes[0].node.payment_is_probe(&payment_hash, &payment_id));
1282                         assert!(!nodes[1].node.payment_is_probe(&payment_hash, &payment_id));
1283                         assert!(!nodes[2].node.payment_is_probe(&payment_hash, &payment_id));
1284                 },
1285                 _ => panic!(),
1286         }
1287
1288         get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
1289         check_added_monitors!(nodes[0], 1);
1290 }
1291
1292 #[test]
1293 fn successful_probe_yields_event() {
1294         let chanmon_cfgs = create_chanmon_cfgs(3);
1295         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1296         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None, None]);
1297         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1298
1299         create_announced_chan_between_nodes(&nodes, 0, 1);
1300         create_announced_chan_between_nodes(&nodes, 1, 2);
1301
1302         let recv_value = 100_000;
1303         let (route, _, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[2], recv_value);
1304
1305         let res = nodes[0].node.send_probe(route.paths[0].clone()).unwrap();
1306
1307         let expected_route: &[&[&Node]] = &[&[&nodes[1], &nodes[2]]];
1308
1309         send_probe_along_route(&nodes[0], expected_route);
1310
1311         expect_probe_successful_events(&nodes[0], vec![res]);
1312
1313         assert!(!nodes[0].node.has_pending_payments());
1314 }
1315
1316 #[test]
1317 fn failed_probe_yields_event() {
1318         let chanmon_cfgs = create_chanmon_cfgs(3);
1319         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1320         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None, None]);
1321         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1322
1323         create_announced_chan_between_nodes(&nodes, 0, 1);
1324         create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 100000, 90000000);
1325
1326         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), 42);
1327
1328         let (route, _, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[2], payment_params, 9_998_000);
1329
1330         let (payment_hash, payment_id) = nodes[0].node.send_probe(route.paths[0].clone()).unwrap();
1331
1332         // node[0] -- update_add_htlcs -> node[1]
1333         check_added_monitors!(nodes[0], 1);
1334         let updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
1335         let probe_event = SendEvent::from_commitment_update(nodes[1].node.get_our_node_id(), updates);
1336         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &probe_event.msgs[0]);
1337         check_added_monitors!(nodes[1], 0);
1338         commitment_signed_dance!(nodes[1], nodes[0], probe_event.commitment_msg, false);
1339         expect_pending_htlcs_forwardable!(nodes[1]);
1340
1341         // node[0] <- update_fail_htlcs -- node[1]
1342         check_added_monitors!(nodes[1], 1);
1343         let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
1344         // Skip the PendingHTLCsForwardable event
1345         let _events = nodes[1].node.get_and_clear_pending_events();
1346         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
1347         check_added_monitors!(nodes[0], 0);
1348         commitment_signed_dance!(nodes[0], nodes[1], updates.commitment_signed, false);
1349
1350         let mut events = nodes[0].node.get_and_clear_pending_events();
1351         assert_eq!(events.len(), 1);
1352         match events.drain(..).next().unwrap() {
1353                 crate::events::Event::ProbeFailed { payment_id: ev_pid, payment_hash: ev_ph, .. } => {
1354                         assert_eq!(payment_id, ev_pid);
1355                         assert_eq!(payment_hash, ev_ph);
1356                 },
1357                 _ => panic!(),
1358         };
1359         assert!(!nodes[0].node.has_pending_payments());
1360 }
1361
1362 #[test]
1363 fn onchain_failed_probe_yields_event() {
1364         // Tests that an attempt to probe over a channel that is eventaully closed results in a failure
1365         // event.
1366         let chanmon_cfgs = create_chanmon_cfgs(3);
1367         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1368         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1369         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1370
1371         let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;
1372         create_announced_chan_between_nodes(&nodes, 1, 2);
1373
1374         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), 42);
1375
1376         // Send a dust HTLC, which will be treated as if it timed out once the channel hits the chain.
1377         let (route, _, _, _) = get_route_and_payment_hash!(&nodes[0], nodes[2], payment_params, 1_000);
1378         let (payment_hash, payment_id) = nodes[0].node.send_probe(route.paths[0].clone()).unwrap();
1379
1380         // node[0] -- update_add_htlcs -> node[1]
1381         check_added_monitors!(nodes[0], 1);
1382         let updates = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
1383         let probe_event = SendEvent::from_commitment_update(nodes[1].node.get_our_node_id(), updates);
1384         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &probe_event.msgs[0]);
1385         check_added_monitors!(nodes[1], 0);
1386         commitment_signed_dance!(nodes[1], nodes[0], probe_event.commitment_msg, false);
1387         expect_pending_htlcs_forwardable!(nodes[1]);
1388
1389         check_added_monitors!(nodes[1], 1);
1390         let _ = get_htlc_update_msgs!(nodes[1], nodes[2].node.get_our_node_id());
1391
1392         // Don't bother forwarding the HTLC onwards and just confirm the force-close transaction on
1393         // Node A, which after 6 confirmations should result in a probe failure event.
1394         let bs_txn = get_local_commitment_txn!(nodes[1], chan_id);
1395         confirm_transaction(&nodes[0], &bs_txn[0]);
1396         check_closed_broadcast!(&nodes[0], true);
1397         check_added_monitors!(nodes[0], 1);
1398
1399         let mut events = nodes[0].node.get_and_clear_pending_events();
1400         assert_eq!(events.len(), 2);
1401         let mut found_probe_failed = false;
1402         for event in events.drain(..) {
1403                 match event {
1404                         Event::ProbeFailed { payment_id: ev_pid, payment_hash: ev_ph, .. } => {
1405                                 assert_eq!(payment_id, ev_pid);
1406                                 assert_eq!(payment_hash, ev_ph);
1407                                 found_probe_failed = true;
1408                         },
1409                         Event::ChannelClosed { .. } => {},
1410                         _ => panic!(),
1411                 }
1412         }
1413         assert!(found_probe_failed);
1414         assert!(!nodes[0].node.has_pending_payments());
1415 }
1416
1417 #[test]
1418 fn preflight_probes_yield_event_skip_private_hop() {
1419         let chanmon_cfgs = create_chanmon_cfgs(5);
1420         let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
1421
1422         // We alleviate the HTLC max-in-flight limit, as otherwise we'd always be limited through that.
1423         let mut no_htlc_limit_config = test_default_channel_config();
1424         no_htlc_limit_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100;
1425
1426         let user_configs = std::iter::repeat(no_htlc_limit_config).take(5).map(|c| Some(c)).collect::<Vec<Option<UserConfig>>>();
1427         let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &user_configs);
1428         let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
1429
1430         // Setup channel topology:
1431         //            N0 -(1M:0)- N1 -(1M:0)- N2 -(70k:0)- N3 -(50k:0)- N4
1432
1433         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
1434         create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0);
1435         create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 70_000, 0);
1436         create_unannounced_chan_between_nodes_with_value(&nodes, 3, 4, 50_000, 0);
1437
1438         let mut invoice_features = Bolt11InvoiceFeatures::empty();
1439         invoice_features.set_basic_mpp_optional();
1440
1441         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
1442                 .with_bolt11_features(invoice_features).unwrap();
1443
1444         let recv_value = 50_000_000;
1445         let route_params = RouteParameters::from_payment_params_and_value(payment_params, recv_value);
1446         let res = nodes[0].node.send_preflight_probes(route_params, None).unwrap();
1447
1448         let expected_route: &[&[&Node]] = &[&[&nodes[1], &nodes[2], &nodes[3]]];
1449
1450         assert_eq!(res.len(), expected_route.len());
1451
1452         send_probe_along_route(&nodes[0], expected_route);
1453
1454         expect_probe_successful_events(&nodes[0], res.clone());
1455
1456         assert!(!nodes[0].node.has_pending_payments());
1457 }
1458
1459 #[test]
1460 fn preflight_probes_yield_event() {
1461         let chanmon_cfgs = create_chanmon_cfgs(4);
1462         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
1463
1464         // We alleviate the HTLC max-in-flight limit, as otherwise we'd always be limited through that.
1465         let mut no_htlc_limit_config = test_default_channel_config();
1466         no_htlc_limit_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100;
1467
1468         let user_configs = std::iter::repeat(no_htlc_limit_config).take(4).map(|c| Some(c)).collect::<Vec<Option<UserConfig>>>();
1469         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &user_configs);
1470         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
1471
1472         // Setup channel topology:
1473         //                    (1M:0)- N1 -(30k:0)
1474         //                   /                  \
1475         //                 N0                    N4
1476         //                   \                  /
1477         //                    (1M:0)- N2 -(70k:0)
1478         //
1479         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
1480         create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
1481         create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 30_000, 0);
1482         create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 70_000, 0);
1483
1484         let mut invoice_features = Bolt11InvoiceFeatures::empty();
1485         invoice_features.set_basic_mpp_optional();
1486
1487         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
1488                 .with_bolt11_features(invoice_features).unwrap();
1489
1490         let recv_value = 50_000_000;
1491         let route_params = RouteParameters::from_payment_params_and_value(payment_params, recv_value);
1492         let res = nodes[0].node.send_preflight_probes(route_params, None).unwrap();
1493
1494         let expected_route: &[&[&Node]] = &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]];
1495
1496         assert_eq!(res.len(), expected_route.len());
1497
1498         send_probe_along_route(&nodes[0], expected_route);
1499
1500         expect_probe_successful_events(&nodes[0], res.clone());
1501
1502         assert!(!nodes[0].node.has_pending_payments());
1503 }
1504
1505 #[test]
1506 fn preflight_probes_yield_event_and_skip() {
1507         let chanmon_cfgs = create_chanmon_cfgs(5);
1508         let node_cfgs = create_node_cfgs(5, &chanmon_cfgs);
1509
1510         // We alleviate the HTLC max-in-flight limit, as otherwise we'd always be limited through that.
1511         let mut no_htlc_limit_config = test_default_channel_config();
1512         no_htlc_limit_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100;
1513
1514         let user_configs = std::iter::repeat(no_htlc_limit_config).take(5).map(|c| Some(c)).collect::<Vec<Option<UserConfig>>>();
1515         let node_chanmgrs = create_node_chanmgrs(5, &node_cfgs, &user_configs);
1516         let nodes = create_network(5, &node_cfgs, &node_chanmgrs);
1517
1518         // Setup channel topology:
1519         //                    (30k:0)- N2 -(1M:0)
1520         //                   /                  \
1521         //  N0 -(100k:0)-> N1                    N4
1522         //                   \                  /
1523         //                    (70k:0)- N3 -(1M:0)
1524         //
1525         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
1526         create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 30_000, 0);
1527         create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 70_000, 0);
1528         create_announced_chan_between_nodes_with_value(&nodes, 2, 4, 1_000_000, 0);
1529         create_announced_chan_between_nodes_with_value(&nodes, 3, 4, 1_000_000, 0);
1530
1531         let mut invoice_features = Bolt11InvoiceFeatures::empty();
1532         invoice_features.set_basic_mpp_optional();
1533
1534         let payment_params = PaymentParameters::from_node_id(nodes[4].node.get_our_node_id(), TEST_FINAL_CLTV)
1535                 .with_bolt11_features(invoice_features).unwrap();
1536
1537         let recv_value = 80_000_000;
1538         let route_params = RouteParameters::from_payment_params_and_value(payment_params, recv_value);
1539         let res = nodes[0].node.send_preflight_probes(route_params, None).unwrap();
1540
1541         let expected_route : &[&[&Node]] = &[&[&nodes[1], &nodes[2], &nodes[4]]];
1542
1543         // We check that only one probe was sent, the other one was skipped due to limited liquidity.
1544         assert_eq!(res.len(), 1);
1545
1546         send_probe_along_route(&nodes[0], expected_route);
1547
1548         expect_probe_successful_events(&nodes[0], res.clone());
1549
1550         assert!(!nodes[0].node.has_pending_payments());
1551 }
1552
1553 #[test]
1554 fn claimed_send_payment_idempotent() {
1555         // Tests that `send_payment` (and friends) are (reasonably) idempotent.
1556         let chanmon_cfgs = create_chanmon_cfgs(2);
1557         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1558         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1559         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1560
1561         create_announced_chan_between_nodes(&nodes, 0, 1).2;
1562
1563         let (route, second_payment_hash, second_payment_preimage, second_payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
1564         let (first_payment_preimage, _, _, payment_id) = send_along_route(&nodes[0], route.clone(), &[&nodes[1]], 100_000);
1565
1566         macro_rules! check_send_rejected {
1567                 () => {
1568                         // If we try to resend a new payment with a different payment_hash but with the same
1569                         // payment_id, it should be rejected.
1570                         let send_result = nodes[0].node.send_payment_with_route(&route, second_payment_hash,
1571                                 RecipientOnionFields::secret_only(second_payment_secret), payment_id);
1572                         match send_result {
1573                                 Err(PaymentSendFailure::DuplicatePayment) => {},
1574                                 _ => panic!("Unexpected send result: {:?}", send_result),
1575                         }
1576
1577                         // Further, if we try to send a spontaneous payment with the same payment_id it should
1578                         // also be rejected.
1579                         let send_result = nodes[0].node.send_spontaneous_payment(
1580                                 &route, None, RecipientOnionFields::spontaneous_empty(), payment_id);
1581                         match send_result {
1582                                 Err(PaymentSendFailure::DuplicatePayment) => {},
1583                                 _ => panic!("Unexpected send result: {:?}", send_result),
1584                         }
1585                 }
1586         }
1587
1588         check_send_rejected!();
1589
1590         // Claim the payment backwards, but note that the PaymentSent event is still pending and has
1591         // not been seen by the user. At this point, from the user perspective nothing has changed, so
1592         // we must remain just as idempotent as we were before.
1593         do_claim_payment_along_route(
1594                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1]]], first_payment_preimage)
1595         );
1596
1597         for _ in 0..=IDEMPOTENCY_TIMEOUT_TICKS {
1598                 nodes[0].node.timer_tick_occurred();
1599         }
1600
1601         check_send_rejected!();
1602
1603         // Once the user sees and handles the `PaymentSent` event, we expect them to no longer call
1604         // `send_payment`, and our idempotency guarantees are off - they should have atomically marked
1605         // the payment complete. However, they could have called `send_payment` while the event was
1606         // being processed, leading to a race in our idempotency guarantees. Thus, even immediately
1607         // after the event is handled a duplicate payment should sitll be rejected.
1608         expect_payment_sent!(&nodes[0], first_payment_preimage, Some(0));
1609         check_send_rejected!();
1610
1611         // If relatively little time has passed, a duplicate payment should still fail.
1612         nodes[0].node.timer_tick_occurred();
1613         check_send_rejected!();
1614
1615         // However, after some time has passed (at least more than the one timer tick above), a
1616         // duplicate payment should go through, as ChannelManager should no longer have any remaining
1617         // references to the old payment data.
1618         for _ in 0..IDEMPOTENCY_TIMEOUT_TICKS {
1619                 nodes[0].node.timer_tick_occurred();
1620         }
1621
1622         nodes[0].node.send_payment_with_route(&route, second_payment_hash,
1623                 RecipientOnionFields::secret_only(second_payment_secret), payment_id).unwrap();
1624         check_added_monitors!(nodes[0], 1);
1625         pass_along_route(&nodes[0], &[&[&nodes[1]]], 100_000, second_payment_hash, second_payment_secret);
1626         claim_payment(&nodes[0], &[&nodes[1]], second_payment_preimage);
1627 }
1628
1629 #[test]
1630 fn abandoned_send_payment_idempotent() {
1631         // Tests that `send_payment` (and friends) allow duplicate PaymentIds immediately after
1632         // abandon_payment.
1633         let chanmon_cfgs = create_chanmon_cfgs(2);
1634         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1635         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1636         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1637
1638         create_announced_chan_between_nodes(&nodes, 0, 1).2;
1639
1640         let (route, second_payment_hash, second_payment_preimage, second_payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
1641         let (_, first_payment_hash, _, payment_id) = send_along_route(&nodes[0], route.clone(), &[&nodes[1]], 100_000);
1642
1643         macro_rules! check_send_rejected {
1644                 () => {
1645                         // If we try to resend a new payment with a different payment_hash but with the same
1646                         // payment_id, it should be rejected.
1647                         let send_result = nodes[0].node.send_payment_with_route(&route, second_payment_hash,
1648                                 RecipientOnionFields::secret_only(second_payment_secret), payment_id);
1649                         match send_result {
1650                                 Err(PaymentSendFailure::DuplicatePayment) => {},
1651                                 _ => panic!("Unexpected send result: {:?}", send_result),
1652                         }
1653
1654                         // Further, if we try to send a spontaneous payment with the same payment_id it should
1655                         // also be rejected.
1656                         let send_result = nodes[0].node.send_spontaneous_payment(
1657                                 &route, None, RecipientOnionFields::spontaneous_empty(), payment_id);
1658                         match send_result {
1659                                 Err(PaymentSendFailure::DuplicatePayment) => {},
1660                                 _ => panic!("Unexpected send result: {:?}", send_result),
1661                         }
1662                 }
1663         }
1664
1665         check_send_rejected!();
1666
1667         nodes[1].node.fail_htlc_backwards(&first_payment_hash);
1668         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], [HTLCDestination::FailedPayment { payment_hash: first_payment_hash }]);
1669
1670         // Until we abandon the payment upon path failure, no matter how many timer ticks pass, we still cannot reuse the
1671         // PaymentId.
1672         for _ in 0..=IDEMPOTENCY_TIMEOUT_TICKS {
1673                 nodes[0].node.timer_tick_occurred();
1674         }
1675         check_send_rejected!();
1676
1677         pass_failed_payment_back(&nodes[0], &[&[&nodes[1]]], false, first_payment_hash, PaymentFailureReason::RecipientRejected);
1678
1679         // However, we can reuse the PaymentId immediately after we `abandon_payment` upon passing the
1680         // failed payment back.
1681         nodes[0].node.send_payment_with_route(&route, second_payment_hash,
1682                 RecipientOnionFields::secret_only(second_payment_secret), payment_id).unwrap();
1683         check_added_monitors!(nodes[0], 1);
1684         pass_along_route(&nodes[0], &[&[&nodes[1]]], 100_000, second_payment_hash, second_payment_secret);
1685         claim_payment(&nodes[0], &[&nodes[1]], second_payment_preimage);
1686 }
1687
1688 #[derive(PartialEq)]
1689 enum InterceptTest {
1690         Forward,
1691         Fail,
1692         Timeout,
1693 }
1694
1695 #[test]
1696 fn test_trivial_inflight_htlc_tracking(){
1697         // In this test, we test three scenarios:
1698         // (1) Sending + claiming a payment successfully should return `None` when querying InFlightHtlcs
1699         // (2) Sending a payment without claiming it should return the payment's value (500000) when querying InFlightHtlcs
1700         // (3) After we claim the payment sent in (2), InFlightHtlcs should return `None` for the query.
1701         let chanmon_cfgs = create_chanmon_cfgs(3);
1702         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1703         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
1704         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1705
1706         let (_, _, chan_1_id, _) = create_announced_chan_between_nodes(&nodes, 0, 1);
1707         let (_, _, chan_2_id, _) = create_announced_chan_between_nodes(&nodes, 1, 2);
1708
1709         // Send and claim the payment. Inflight HTLCs should be empty.
1710         let (_, payment_hash, _, payment_id) = send_payment(&nodes[0], &[&nodes[1], &nodes[2]], 500000);
1711         let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
1712         {
1713                 let mut node_0_per_peer_lock;
1714                 let mut node_0_peer_state_lock;
1715                 let channel_1 =  get_channel_ref!(&nodes[0], nodes[1], node_0_per_peer_lock, node_0_peer_state_lock, chan_1_id);
1716
1717                 let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
1718                         &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
1719                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
1720                         channel_1.context().get_short_channel_id().unwrap()
1721                 );
1722                 assert_eq!(chan_1_used_liquidity, None);
1723         }
1724         {
1725                 let mut node_1_per_peer_lock;
1726                 let mut node_1_peer_state_lock;
1727                 let channel_2 =  get_channel_ref!(&nodes[1], nodes[2], node_1_per_peer_lock, node_1_peer_state_lock, chan_2_id);
1728
1729                 let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
1730                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
1731                         &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
1732                         channel_2.context().get_short_channel_id().unwrap()
1733                 );
1734
1735                 assert_eq!(chan_2_used_liquidity, None);
1736         }
1737         let pending_payments = nodes[0].node.list_recent_payments();
1738         assert_eq!(pending_payments.len(), 1);
1739         assert_eq!(pending_payments[0], RecentPaymentDetails::Fulfilled { payment_hash: Some(payment_hash), payment_id });
1740
1741         // Remove fulfilled payment
1742         for _ in 0..=IDEMPOTENCY_TIMEOUT_TICKS {
1743                 nodes[0].node.timer_tick_occurred();
1744         }
1745
1746         // Send the payment, but do not claim it. Our inflight HTLCs should contain the pending payment.
1747         let (payment_preimage, payment_hash,  _, payment_id) = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 500000);
1748         let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
1749         {
1750                 let mut node_0_per_peer_lock;
1751                 let mut node_0_peer_state_lock;
1752                 let channel_1 =  get_channel_ref!(&nodes[0], nodes[1], node_0_per_peer_lock, node_0_peer_state_lock, chan_1_id);
1753
1754                 let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
1755                         &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
1756                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
1757                         channel_1.context().get_short_channel_id().unwrap()
1758                 );
1759                 // First hop accounts for expected 1000 msat fee
1760                 assert_eq!(chan_1_used_liquidity, Some(501000));
1761         }
1762         {
1763                 let mut node_1_per_peer_lock;
1764                 let mut node_1_peer_state_lock;
1765                 let channel_2 =  get_channel_ref!(&nodes[1], nodes[2], node_1_per_peer_lock, node_1_peer_state_lock, chan_2_id);
1766
1767                 let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
1768                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
1769                         &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
1770                         channel_2.context().get_short_channel_id().unwrap()
1771                 );
1772
1773                 assert_eq!(chan_2_used_liquidity, Some(500000));
1774         }
1775         let pending_payments = nodes[0].node.list_recent_payments();
1776         assert_eq!(pending_payments.len(), 1);
1777         assert_eq!(pending_payments[0], RecentPaymentDetails::Pending { payment_id, payment_hash, total_msat: 500000 });
1778
1779         // Now, let's claim the payment. This should result in the used liquidity to return `None`.
1780         claim_payment(&nodes[0], &[&nodes[1], &nodes[2]], payment_preimage);
1781
1782         // Remove fulfilled payment
1783         for _ in 0..=IDEMPOTENCY_TIMEOUT_TICKS {
1784                 nodes[0].node.timer_tick_occurred();
1785         }
1786
1787         let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
1788         {
1789                 let mut node_0_per_peer_lock;
1790                 let mut node_0_peer_state_lock;
1791                 let channel_1 =  get_channel_ref!(&nodes[0], nodes[1], node_0_per_peer_lock, node_0_peer_state_lock, chan_1_id);
1792
1793                 let chan_1_used_liquidity = inflight_htlcs.used_liquidity_msat(
1794                         &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
1795                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
1796                         channel_1.context().get_short_channel_id().unwrap()
1797                 );
1798                 assert_eq!(chan_1_used_liquidity, None);
1799         }
1800         {
1801                 let mut node_1_per_peer_lock;
1802                 let mut node_1_peer_state_lock;
1803                 let channel_2 =  get_channel_ref!(&nodes[1], nodes[2], node_1_per_peer_lock, node_1_peer_state_lock, chan_2_id);
1804
1805                 let chan_2_used_liquidity = inflight_htlcs.used_liquidity_msat(
1806                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()) ,
1807                         &NodeId::from_pubkey(&nodes[2].node.get_our_node_id()),
1808                         channel_2.context().get_short_channel_id().unwrap()
1809                 );
1810                 assert_eq!(chan_2_used_liquidity, None);
1811         }
1812
1813         let pending_payments = nodes[0].node.list_recent_payments();
1814         assert_eq!(pending_payments.len(), 0);
1815 }
1816
1817 #[test]
1818 fn test_holding_cell_inflight_htlcs() {
1819         let chanmon_cfgs = create_chanmon_cfgs(2);
1820         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
1821         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
1822         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
1823         let channel_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;
1824
1825         let (route, payment_hash_1, _, payment_secret_1) = get_route_and_payment_hash!(nodes[0], nodes[1], 1000000);
1826         let (_, payment_hash_2, payment_secret_2) = get_payment_preimage_hash!(nodes[1]);
1827
1828         // Queue up two payments - one will be delivered right away, one immediately goes into the
1829         // holding cell as nodes[0] is AwaitingRAA.
1830         {
1831                 nodes[0].node.send_payment_with_route(&route, payment_hash_1,
1832                         RecipientOnionFields::secret_only(payment_secret_1), PaymentId(payment_hash_1.0)).unwrap();
1833                 check_added_monitors!(nodes[0], 1);
1834                 nodes[0].node.send_payment_with_route(&route, payment_hash_2,
1835                         RecipientOnionFields::secret_only(payment_secret_2), PaymentId(payment_hash_2.0)).unwrap();
1836                 check_added_monitors!(nodes[0], 0);
1837         }
1838
1839         let inflight_htlcs = node_chanmgrs[0].compute_inflight_htlcs();
1840
1841         {
1842                 let mut node_0_per_peer_lock;
1843                 let mut node_0_peer_state_lock;
1844                 let channel =  get_channel_ref!(&nodes[0], nodes[1], node_0_per_peer_lock, node_0_peer_state_lock, channel_id);
1845
1846                 let used_liquidity = inflight_htlcs.used_liquidity_msat(
1847                         &NodeId::from_pubkey(&nodes[0].node.get_our_node_id()) ,
1848                         &NodeId::from_pubkey(&nodes[1].node.get_our_node_id()),
1849                         channel.context().get_short_channel_id().unwrap()
1850                 );
1851
1852                 assert_eq!(used_liquidity, Some(2000000));
1853         }
1854
1855         // Clear pending events so test doesn't throw a "Had excess message on node..." error
1856         nodes[0].node.get_and_clear_pending_msg_events();
1857 }
1858
1859 #[test]
1860 fn intercepted_payment() {
1861         // Test that detecting an intercept scid on payment forward will signal LDK to generate an
1862         // intercept event, which the LSP can then use to either (a) open a JIT channel to forward the
1863         // payment or (b) fail the payment.
1864         do_test_intercepted_payment(InterceptTest::Forward);
1865         do_test_intercepted_payment(InterceptTest::Fail);
1866         // Make sure that intercepted payments will be automatically failed back if too many blocks pass.
1867         do_test_intercepted_payment(InterceptTest::Timeout);
1868 }
1869
1870 fn do_test_intercepted_payment(test: InterceptTest) {
1871         let chanmon_cfgs = create_chanmon_cfgs(3);
1872         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
1873
1874         let mut zero_conf_chan_config = test_default_channel_config();
1875         zero_conf_chan_config.manually_accept_inbound_channels = true;
1876         let mut intercept_forwards_config = test_default_channel_config();
1877         intercept_forwards_config.accept_intercept_htlcs = true;
1878         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(intercept_forwards_config), Some(zero_conf_chan_config)]);
1879
1880         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
1881         let scorer = test_utils::TestScorer::new();
1882         let random_seed_bytes = chanmon_cfgs[0].keys_manager.get_secure_random_bytes();
1883
1884         let _ = create_announced_chan_between_nodes(&nodes, 0, 1).2;
1885
1886         let amt_msat = 100_000;
1887         let intercept_scid = nodes[1].node.get_intercept_scid();
1888         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), TEST_FINAL_CLTV)
1889                 .with_route_hints(vec![
1890                         RouteHint(vec![RouteHintHop {
1891                                 src_node_id: nodes[1].node.get_our_node_id(),
1892                                 short_channel_id: intercept_scid,
1893                                 fees: RoutingFees {
1894                                         base_msat: 1000,
1895                                         proportional_millionths: 0,
1896                                 },
1897                                 cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
1898                                 htlc_minimum_msat: None,
1899                                 htlc_maximum_msat: None,
1900                         }])
1901                 ]).unwrap()
1902                 .with_bolt11_features(nodes[2].node.bolt11_invoice_features()).unwrap();
1903         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
1904         let route = get_route(
1905                 &nodes[0].node.get_our_node_id(), &route_params, &nodes[0].network_graph.read_only(), None,
1906                 nodes[0].logger, &scorer, &Default::default(), &random_seed_bytes
1907         ).unwrap();
1908
1909         let (payment_hash, payment_secret) = nodes[2].node.create_inbound_payment(Some(amt_msat), 60 * 60, None).unwrap();
1910         nodes[0].node.send_payment_with_route(&route, payment_hash,
1911                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
1912         let payment_event = {
1913                 {
1914                         let mut added_monitors = nodes[0].chain_monitor.added_monitors.lock().unwrap();
1915                         assert_eq!(added_monitors.len(), 1);
1916                         added_monitors.clear();
1917                 }
1918                 let mut events = nodes[0].node.get_and_clear_pending_msg_events();
1919                 assert_eq!(events.len(), 1);
1920                 SendEvent::from_event(events.remove(0))
1921         };
1922         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
1923         commitment_signed_dance!(nodes[1], nodes[0], &payment_event.commitment_msg, false, true);
1924
1925         // Check that we generate the PaymentIntercepted event when an intercept forward is detected.
1926         let events = nodes[1].node.get_and_clear_pending_events();
1927         assert_eq!(events.len(), 1);
1928         let (intercept_id, expected_outbound_amount_msat) = match events[0] {
1929                 crate::events::Event::HTLCIntercepted {
1930                         intercept_id, expected_outbound_amount_msat, payment_hash: pmt_hash, inbound_amount_msat, requested_next_hop_scid: short_channel_id
1931                 } => {
1932                         assert_eq!(pmt_hash, payment_hash);
1933                         assert_eq!(inbound_amount_msat, route.get_total_amount() + route.get_total_fees());
1934                         assert_eq!(short_channel_id, intercept_scid);
1935                         (intercept_id, expected_outbound_amount_msat)
1936                 },
1937                 _ => panic!()
1938         };
1939
1940         // Check for unknown channel id error.
1941         let unknown_chan_id_err = nodes[1].node.forward_intercepted_htlc(intercept_id, &ChannelId::from_bytes([42; 32]), nodes[2].node.get_our_node_id(), expected_outbound_amount_msat).unwrap_err();
1942         assert_eq!(unknown_chan_id_err , APIError::ChannelUnavailable  {
1943                 err: format!("Channel with id {} not found for the passed counterparty node_id {}",
1944                         log_bytes!([42; 32]), nodes[2].node.get_our_node_id()) });
1945
1946         if test == InterceptTest::Fail {
1947                 // Ensure we can fail the intercepted payment back.
1948                 nodes[1].node.fail_intercepted_htlc(intercept_id).unwrap();
1949                 expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[1], vec![HTLCDestination::UnknownNextHop { requested_forward_scid: intercept_scid }]);
1950                 nodes[1].node.process_pending_htlc_forwards();
1951                 let update_fail = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
1952                 check_added_monitors!(&nodes[1], 1);
1953                 assert!(update_fail.update_fail_htlcs.len() == 1);
1954                 let fail_msg = update_fail.update_fail_htlcs[0].clone();
1955                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &fail_msg);
1956                 commitment_signed_dance!(nodes[0], nodes[1], update_fail.commitment_signed, false);
1957
1958                 // Ensure the payment fails with the expected error.
1959                 let fail_conditions = PaymentFailedConditions::new()
1960                         .blamed_scid(intercept_scid)
1961                         .blamed_chan_closed(true)
1962                         .expected_htlc_error_data(0x4000 | 10, &[]);
1963                 expect_payment_failed_conditions(&nodes[0], payment_hash, false, fail_conditions);
1964         } else if test == InterceptTest::Forward {
1965                 // Check that we'll fail as expected when sending to a channel that isn't in `ChannelReady` yet.
1966                 let temp_chan_id = nodes[1].node.create_channel(nodes[2].node.get_our_node_id(), 100_000, 0, 42, None, None).unwrap();
1967                 let unusable_chan_err = nodes[1].node.forward_intercepted_htlc(intercept_id, &temp_chan_id, nodes[2].node.get_our_node_id(), expected_outbound_amount_msat).unwrap_err();
1968                 assert_eq!(unusable_chan_err , APIError::ChannelUnavailable {
1969                         err: format!("Channel with id {} for the passed counterparty node_id {} is still opening.",
1970                                 temp_chan_id, nodes[2].node.get_our_node_id()) });
1971                 assert_eq!(nodes[1].node.get_and_clear_pending_msg_events().len(), 1);
1972
1973                 // Open the just-in-time channel so the payment can then be forwarded.
1974                 let (_, channel_id) = open_zero_conf_channel(&nodes[1], &nodes[2], None);
1975
1976                 // Finally, forward the intercepted payment through and claim it.
1977                 nodes[1].node.forward_intercepted_htlc(intercept_id, &channel_id, nodes[2].node.get_our_node_id(), expected_outbound_amount_msat).unwrap();
1978                 expect_pending_htlcs_forwardable!(nodes[1]);
1979
1980                 let payment_event = {
1981                         {
1982                                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
1983                                 assert_eq!(added_monitors.len(), 1);
1984                                 added_monitors.clear();
1985                         }
1986                         let mut events = nodes[1].node.get_and_clear_pending_msg_events();
1987                         assert_eq!(events.len(), 1);
1988                         SendEvent::from_event(events.remove(0))
1989                 };
1990                 nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event.msgs[0]);
1991                 commitment_signed_dance!(nodes[2], nodes[1], &payment_event.commitment_msg, false, true);
1992                 expect_pending_htlcs_forwardable!(nodes[2]);
1993
1994                 let payment_preimage = nodes[2].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
1995                 expect_payment_claimable!(&nodes[2], payment_hash, payment_secret, amt_msat, Some(payment_preimage), nodes[2].node.get_our_node_id());
1996                 do_claim_payment_along_route(
1997                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
1998                 );
1999                 let events = nodes[0].node.get_and_clear_pending_events();
2000                 assert_eq!(events.len(), 2);
2001                 match events[0] {
2002                         Event::PaymentSent { payment_preimage: ref ev_preimage, payment_hash: ref ev_hash, ref fee_paid_msat, .. } => {
2003                                 assert_eq!(payment_preimage, *ev_preimage);
2004                                 assert_eq!(payment_hash, *ev_hash);
2005                                 assert_eq!(fee_paid_msat, &Some(1000));
2006                         },
2007                         _ => panic!("Unexpected event")
2008                 }
2009                 match events[1] {
2010                         Event::PaymentPathSuccessful { payment_hash: hash, .. } => {
2011                                 assert_eq!(hash, Some(payment_hash));
2012                         },
2013                         _ => panic!("Unexpected event")
2014                 }
2015                 check_added_monitors(&nodes[0], 1);
2016         } else if test == InterceptTest::Timeout {
2017                 let mut block = create_dummy_block(nodes[0].best_block_hash(), 42, Vec::new());
2018                 connect_block(&nodes[0], &block);
2019                 connect_block(&nodes[1], &block);
2020                 for _ in 0..TEST_FINAL_CLTV {
2021                         block.header.prev_blockhash = block.block_hash();
2022                         connect_block(&nodes[0], &block);
2023                         connect_block(&nodes[1], &block);
2024                 }
2025                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], vec![HTLCDestination::InvalidForward { requested_forward_scid: intercept_scid }]);
2026                 check_added_monitors!(nodes[1], 1);
2027                 let htlc_timeout_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2028                 assert!(htlc_timeout_updates.update_add_htlcs.is_empty());
2029                 assert_eq!(htlc_timeout_updates.update_fail_htlcs.len(), 1);
2030                 assert!(htlc_timeout_updates.update_fail_malformed_htlcs.is_empty());
2031                 assert!(htlc_timeout_updates.update_fee.is_none());
2032
2033                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_timeout_updates.update_fail_htlcs[0]);
2034                 commitment_signed_dance!(nodes[0], nodes[1], htlc_timeout_updates.commitment_signed, false);
2035                 expect_payment_failed!(nodes[0], payment_hash, false, 0x2000 | 2, []);
2036
2037                 // Check for unknown intercept id error.
2038                 let (_, channel_id) = open_zero_conf_channel(&nodes[1], &nodes[2], None);
2039                 let unknown_intercept_id_err = nodes[1].node.forward_intercepted_htlc(intercept_id, &channel_id, nodes[2].node.get_our_node_id(), expected_outbound_amount_msat).unwrap_err();
2040                 assert_eq!(unknown_intercept_id_err , APIError::APIMisuseError { err: format!("Payment with intercept id {} not found", log_bytes!(intercept_id.0)) });
2041                 let unknown_intercept_id_err = nodes[1].node.fail_intercepted_htlc(intercept_id).unwrap_err();
2042                 assert_eq!(unknown_intercept_id_err , APIError::APIMisuseError { err: format!("Payment with intercept id {} not found", log_bytes!(intercept_id.0)) });
2043         }
2044 }
2045
2046 #[test]
2047 fn accept_underpaying_htlcs_config() {
2048         do_accept_underpaying_htlcs_config(1);
2049         do_accept_underpaying_htlcs_config(2);
2050         do_accept_underpaying_htlcs_config(3);
2051 }
2052
2053 fn do_accept_underpaying_htlcs_config(num_mpp_parts: usize) {
2054         let chanmon_cfgs = create_chanmon_cfgs(3);
2055         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
2056         let max_in_flight_percent = 10;
2057         let mut intercept_forwards_config = test_default_channel_config();
2058         intercept_forwards_config.accept_intercept_htlcs = true;
2059         intercept_forwards_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = max_in_flight_percent;
2060         let mut underpay_config = test_default_channel_config();
2061         underpay_config.channel_config.accept_underpaying_htlcs = true;
2062         underpay_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = max_in_flight_percent;
2063         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(intercept_forwards_config), Some(underpay_config)]);
2064         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
2065
2066         let amt_msat = 900_000;
2067
2068         let mut chan_ids = Vec::new();
2069         for _ in 0..num_mpp_parts {
2070                 // We choose the channel size so that there can be at most one part pending on each channel.
2071                 let channel_size = amt_msat / 1000 / num_mpp_parts as u64 * 100 / max_in_flight_percent as u64 + 100;
2072                 let _ = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, channel_size, 0);
2073                 let channel_id = create_unannounced_chan_between_nodes_with_value(&nodes, 1, 2, channel_size, 0).0.channel_id;
2074                 chan_ids.push(channel_id);
2075         }
2076
2077         // Send the initial payment.
2078         let skimmed_fee_msat = 20;
2079         let mut route_hints = Vec::new();
2080         for _ in 0..num_mpp_parts {
2081                 route_hints.push(RouteHint(vec![RouteHintHop {
2082                         src_node_id: nodes[1].node.get_our_node_id(),
2083                         short_channel_id: nodes[1].node.get_intercept_scid(),
2084                         fees: RoutingFees {
2085                                 base_msat: 1000,
2086                                 proportional_millionths: 0,
2087                         },
2088                         cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA,
2089                         htlc_minimum_msat: None,
2090                         htlc_maximum_msat: Some(amt_msat / num_mpp_parts as u64 + 5),
2091                 }]));
2092         }
2093         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), TEST_FINAL_CLTV)
2094                 .with_route_hints(route_hints).unwrap()
2095                 .with_bolt11_features(nodes[2].node.bolt11_invoice_features()).unwrap();
2096         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2097         let (payment_hash, payment_secret) = nodes[2].node.create_inbound_payment(Some(amt_msat), 60 * 60, None).unwrap();
2098         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2099                 PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
2100         check_added_monitors!(nodes[0], num_mpp_parts); // one monitor per path
2101         let mut events: Vec<SendEvent> = nodes[0].node.get_and_clear_pending_msg_events().into_iter().map(|e| SendEvent::from_event(e)).collect();
2102         assert_eq!(events.len(), num_mpp_parts);
2103
2104         // Forward the intercepted payments.
2105         for (idx, ev) in events.into_iter().enumerate() {
2106                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &ev.msgs[0]);
2107                 do_commitment_signed_dance(&nodes[1], &nodes[0], &ev.commitment_msg, false, true);
2108
2109                 let events = nodes[1].node.get_and_clear_pending_events();
2110                 assert_eq!(events.len(), 1);
2111                 let (intercept_id, expected_outbound_amt_msat) = match events[0] {
2112                         crate::events::Event::HTLCIntercepted {
2113                                 intercept_id, expected_outbound_amount_msat, payment_hash: pmt_hash, ..
2114                         } => {
2115                                 assert_eq!(pmt_hash, payment_hash);
2116                                 (intercept_id, expected_outbound_amount_msat)
2117                         },
2118                         _ => panic!()
2119                 };
2120                 nodes[1].node.forward_intercepted_htlc(intercept_id, &chan_ids[idx],
2121                         nodes[2].node.get_our_node_id(), expected_outbound_amt_msat - skimmed_fee_msat).unwrap();
2122                 expect_pending_htlcs_forwardable!(nodes[1]);
2123                 let payment_event = {
2124                         {
2125                                 let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
2126                                 assert_eq!(added_monitors.len(), 1);
2127                                 added_monitors.clear();
2128                         }
2129                         let mut events = nodes[1].node.get_and_clear_pending_msg_events();
2130                         assert_eq!(events.len(), 1);
2131                         SendEvent::from_event(events.remove(0))
2132                 };
2133                 nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event.msgs[0]);
2134                 do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event.commitment_msg, false, true);
2135                 if idx == num_mpp_parts - 1 {
2136                         expect_pending_htlcs_forwardable!(nodes[2]);
2137                 }
2138         }
2139
2140         // Claim the payment and check that the skimmed fee is as expected.
2141         let payment_preimage = nodes[2].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
2142         let events = nodes[2].node.get_and_clear_pending_events();
2143         assert_eq!(events.len(), 1);
2144         match events[0] {
2145                 crate::events::Event::PaymentClaimable {
2146                         ref payment_hash, ref purpose, amount_msat, counterparty_skimmed_fee_msat, receiver_node_id, ..
2147                 } => {
2148                         assert_eq!(payment_hash, payment_hash);
2149                         assert_eq!(amt_msat - skimmed_fee_msat * num_mpp_parts as u64, amount_msat);
2150                         assert_eq!(skimmed_fee_msat * num_mpp_parts as u64, counterparty_skimmed_fee_msat);
2151                         assert_eq!(nodes[2].node.get_our_node_id(), receiver_node_id.unwrap());
2152                         match purpose {
2153                                 crate::events::PaymentPurpose::Bolt11InvoicePayment {
2154                                         payment_preimage: ev_payment_preimage,
2155                                         payment_secret: ev_payment_secret,
2156                                         ..
2157                                 } => {
2158                                         assert_eq!(payment_preimage, ev_payment_preimage.unwrap());
2159                                         assert_eq!(payment_secret, *ev_payment_secret);
2160                                 },
2161                                 _ => panic!(),
2162                         }
2163                 },
2164                 _ => panic!("Unexpected event"),
2165         }
2166         let mut expected_paths_vecs = Vec::new();
2167         let mut expected_paths = Vec::new();
2168         for _ in 0..num_mpp_parts { expected_paths_vecs.push(vec!(&nodes[1], &nodes[2])); }
2169         for i in 0..num_mpp_parts { expected_paths.push(&expected_paths_vecs[i][..]); }
2170         expected_paths[0].last().unwrap().node.claim_funds(payment_preimage);
2171         let args = ClaimAlongRouteArgs::new(&nodes[0], &expected_paths[..], payment_preimage)
2172                 .with_expected_extra_fees(vec![skimmed_fee_msat as u32; num_mpp_parts]);
2173         let total_fee_msat = pass_claimed_payment_along_route(args);
2174         // The sender doesn't know that the penultimate hop took an extra fee.
2175         expect_payment_sent(&nodes[0], payment_preimage,
2176                 Some(Some(total_fee_msat - skimmed_fee_msat * num_mpp_parts as u64)), true, true);
2177 }
2178
2179 #[derive(PartialEq)]
2180 enum AutoRetry {
2181         Success,
2182         Spontaneous,
2183         FailAttempts,
2184         FailTimeout,
2185         FailOnRestart,
2186         FailOnRetry,
2187 }
2188
2189 #[test]
2190 fn automatic_retries() {
2191         do_automatic_retries(AutoRetry::Success);
2192         do_automatic_retries(AutoRetry::Spontaneous);
2193         do_automatic_retries(AutoRetry::FailAttempts);
2194         do_automatic_retries(AutoRetry::FailTimeout);
2195         do_automatic_retries(AutoRetry::FailOnRestart);
2196         do_automatic_retries(AutoRetry::FailOnRetry);
2197 }
2198 fn do_automatic_retries(test: AutoRetry) {
2199         // Test basic automatic payment retries in ChannelManager. See individual `test` variant comments
2200         // below.
2201         let chanmon_cfgs = create_chanmon_cfgs(3);
2202         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
2203         let persister;
2204         let new_chain_monitor;
2205
2206         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
2207         let node_0_deserialized;
2208
2209         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
2210         let channel_id_1 = create_announced_chan_between_nodes(&nodes, 0, 1).2;
2211         let channel_id_2 = create_announced_chan_between_nodes(&nodes, 2, 1).2;
2212
2213         // Marshall data to send the payment
2214         #[cfg(feature = "std")]
2215         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2216         #[cfg(not(feature = "std"))]
2217         let payment_expiry_secs = 60 * 60;
2218         let amt_msat = 1000;
2219         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2220         invoice_features.set_variable_length_onion_required();
2221         invoice_features.set_payment_secret_required();
2222         invoice_features.set_basic_mpp_optional();
2223         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), TEST_FINAL_CLTV)
2224                 .with_expiry_time(payment_expiry_secs as u64)
2225                 .with_bolt11_features(invoice_features).unwrap();
2226         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2227         let (_, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
2228
2229         macro_rules! pass_failed_attempt_with_retry_along_path {
2230                 ($failing_channel_id: expr, $expect_pending_htlcs_forwardable: expr) => {
2231                         // Send a payment attempt that fails due to lack of liquidity on the second hop
2232                         check_added_monitors!(nodes[0], 1);
2233                         let update_0 = get_htlc_update_msgs!(nodes[0], nodes[1].node.get_our_node_id());
2234                         let mut update_add = update_0.update_add_htlcs[0].clone();
2235                         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add);
2236                         commitment_signed_dance!(nodes[1], nodes[0], &update_0.commitment_signed, false, true);
2237                         expect_pending_htlcs_forwardable_ignore!(nodes[1]);
2238                         nodes[1].node.process_pending_htlc_forwards();
2239                         expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[1],
2240                                 vec![HTLCDestination::NextHopChannel {
2241                                         node_id: Some(nodes[2].node.get_our_node_id()),
2242                                         channel_id: $failing_channel_id,
2243                                 }]);
2244                         nodes[1].node.process_pending_htlc_forwards();
2245                         let update_1 = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2246                         check_added_monitors!(&nodes[1], 1);
2247                         assert!(update_1.update_fail_htlcs.len() == 1);
2248                         let fail_msg = update_1.update_fail_htlcs[0].clone();
2249                         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &fail_msg);
2250                         commitment_signed_dance!(nodes[0], nodes[1], update_1.commitment_signed, false);
2251
2252                         // Ensure the attempt fails and a new PendingHTLCsForwardable event is generated for the retry
2253                         let mut events = nodes[0].node.get_and_clear_pending_events();
2254                         assert_eq!(events.len(), 2);
2255                         match events[0] {
2256                                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
2257                                         assert_eq!(payment_hash, ev_payment_hash);
2258                                         assert_eq!(payment_failed_permanently, false);
2259                                 },
2260                                 _ => panic!("Unexpected event"),
2261                         }
2262                         if $expect_pending_htlcs_forwardable {
2263                                 match events[1] {
2264                                         Event::PendingHTLCsForwardable { .. } => {},
2265                                         _ => panic!("Unexpected event"),
2266                                 }
2267                         } else {
2268                                 match events[1] {
2269                                         Event::PaymentFailed { payment_hash: ev_payment_hash, .. } => {
2270                                                 assert_eq!(payment_hash, ev_payment_hash);
2271                                         },
2272                                         _ => panic!("Unexpected event"),
2273                                 }
2274                         }
2275                 }
2276         }
2277
2278         if test == AutoRetry::Success {
2279                 // Test that we can succeed on the first retry.
2280                 nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2281                         PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2282                 pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2283
2284                 // Open a new channel with liquidity on the second hop so we can find a route for the retry
2285                 // attempt, since the initial second hop channel will be excluded from pathfinding
2286                 create_announced_chan_between_nodes(&nodes, 1, 2);
2287
2288                 // We retry payments in `process_pending_htlc_forwards`
2289                 nodes[0].node.process_pending_htlc_forwards();
2290                 check_added_monitors!(nodes[0], 1);
2291                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2292                 assert_eq!(msg_events.len(), 1);
2293                 pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], amt_msat, payment_hash, Some(payment_secret), msg_events.pop().unwrap(), true, None);
2294                 claim_payment_along_route(
2295                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
2296                 );
2297         } else if test == AutoRetry::Spontaneous {
2298                 nodes[0].node.send_spontaneous_payment_with_retry(Some(payment_preimage),
2299                         RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params,
2300                         Retry::Attempts(1)).unwrap();
2301                 pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2302
2303                 // Open a new channel with liquidity on the second hop so we can find a route for the retry
2304                 // attempt, since the initial second hop channel will be excluded from pathfinding
2305                 create_announced_chan_between_nodes(&nodes, 1, 2);
2306
2307                 // We retry payments in `process_pending_htlc_forwards`
2308                 nodes[0].node.process_pending_htlc_forwards();
2309                 check_added_monitors!(nodes[0], 1);
2310                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2311                 assert_eq!(msg_events.len(), 1);
2312                 pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], amt_msat, payment_hash, None, msg_events.pop().unwrap(), true, Some(payment_preimage));
2313                 claim_payment_along_route(
2314                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
2315                 );
2316         } else if test == AutoRetry::FailAttempts {
2317                 // Ensure ChannelManager will not retry a payment if it has run out of payment attempts.
2318                 nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2319                         PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2320                 pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2321
2322                 // Open a new channel with no liquidity on the second hop so we can find a (bad) route for
2323                 // the retry attempt, since the initial second hop channel will be excluded from pathfinding
2324                 let channel_id_3 = create_announced_chan_between_nodes(&nodes, 2, 1).2;
2325
2326                 // We retry payments in `process_pending_htlc_forwards`
2327                 nodes[0].node.process_pending_htlc_forwards();
2328                 pass_failed_attempt_with_retry_along_path!(channel_id_3, false);
2329
2330                 // Ensure we won't retry a second time.
2331                 nodes[0].node.process_pending_htlc_forwards();
2332                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2333                 assert_eq!(msg_events.len(), 0);
2334         } else if test == AutoRetry::FailTimeout {
2335                 #[cfg(feature = "std")] {
2336                         // Ensure ChannelManager will not retry a payment if it times out due to Retry::Timeout.
2337                         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2338                                 PaymentId(payment_hash.0), route_params, Retry::Timeout(Duration::from_secs(60))).unwrap();
2339                         pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2340
2341                         // Advance the time so the second attempt fails due to timeout.
2342                         SinceEpoch::advance(Duration::from_secs(61));
2343
2344                         // Make sure we don't retry again.
2345                         nodes[0].node.process_pending_htlc_forwards();
2346                         let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2347                         assert_eq!(msg_events.len(), 0);
2348
2349                         let mut events = nodes[0].node.get_and_clear_pending_events();
2350                         assert_eq!(events.len(), 1);
2351                         match events[0] {
2352                                 Event::PaymentFailed { payment_hash: ref ev_payment_hash, payment_id: ref ev_payment_id, reason: ref ev_reason } => {
2353                                         assert_eq!(payment_hash, *ev_payment_hash);
2354                                         assert_eq!(PaymentId(payment_hash.0), *ev_payment_id);
2355                                         assert_eq!(PaymentFailureReason::RetriesExhausted, ev_reason.unwrap());
2356                                 },
2357                                 _ => panic!("Unexpected event"),
2358                         }
2359                 }
2360         } else if test == AutoRetry::FailOnRestart {
2361                 // Ensure ChannelManager will not retry a payment after restart, even if there were retry
2362                 // attempts remaining prior to restart.
2363                 nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2364                         PaymentId(payment_hash.0), route_params, Retry::Attempts(2)).unwrap();
2365                 pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2366
2367                 // Open a new channel with no liquidity on the second hop so we can find a (bad) route for
2368                 // the retry attempt, since the initial second hop channel will be excluded from pathfinding
2369                 let channel_id_3 = create_announced_chan_between_nodes(&nodes, 2, 1).2;
2370
2371                 // Ensure the first retry attempt fails, with 1 retry attempt remaining
2372                 nodes[0].node.process_pending_htlc_forwards();
2373                 pass_failed_attempt_with_retry_along_path!(channel_id_3, true);
2374
2375                 // Restart the node and ensure that ChannelManager does not use its remaining retry attempt
2376                 let node_encoded = nodes[0].node.encode();
2377                 let chan_1_monitor_serialized = get_monitor!(nodes[0], channel_id_1).encode();
2378                 reload_node!(nodes[0], node_encoded, &[&chan_1_monitor_serialized], persister, new_chain_monitor, node_0_deserialized);
2379
2380                 let mut events = nodes[0].node.get_and_clear_pending_events();
2381                 expect_pending_htlcs_forwardable_from_events!(nodes[0], events, true);
2382                 // Make sure we don't retry again.
2383                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2384                 assert_eq!(msg_events.len(), 0);
2385
2386                 let mut events = nodes[0].node.get_and_clear_pending_events();
2387                 assert_eq!(events.len(), 1);
2388                 match events[0] {
2389                         Event::PaymentFailed { payment_hash: ref ev_payment_hash, payment_id: ref ev_payment_id, reason: ref ev_reason } => {
2390                                 assert_eq!(payment_hash, *ev_payment_hash);
2391                                 assert_eq!(PaymentId(payment_hash.0), *ev_payment_id);
2392                                 assert_eq!(PaymentFailureReason::RetriesExhausted, ev_reason.unwrap());
2393                         },
2394                         _ => panic!("Unexpected event"),
2395                 }
2396         } else if test == AutoRetry::FailOnRetry {
2397                 nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2398                         PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2399                 pass_failed_attempt_with_retry_along_path!(channel_id_2, true);
2400
2401                 // We retry payments in `process_pending_htlc_forwards`. Since our channel closed, we should
2402                 // fail to find a route.
2403                 nodes[0].node.process_pending_htlc_forwards();
2404                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2405                 assert_eq!(msg_events.len(), 0);
2406
2407                 let mut events = nodes[0].node.get_and_clear_pending_events();
2408                 assert_eq!(events.len(), 1);
2409                 match events[0] {
2410                         Event::PaymentFailed { payment_hash: ref ev_payment_hash, payment_id: ref ev_payment_id, reason: ref ev_reason } => {
2411                                 assert_eq!(payment_hash, *ev_payment_hash);
2412                                 assert_eq!(PaymentId(payment_hash.0), *ev_payment_id);
2413                                 assert_eq!(PaymentFailureReason::RouteNotFound, ev_reason.unwrap());
2414                         },
2415                         _ => panic!("Unexpected event"),
2416                 }
2417         }
2418 }
2419
2420 #[test]
2421 fn auto_retry_partial_failure() {
2422         // Test that we'll retry appropriately on send partial failure and retry partial failure.
2423         let chanmon_cfgs = create_chanmon_cfgs(2);
2424         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
2425         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
2426         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
2427
2428         // Open three channels, the first has plenty of liquidity, the second and third have ~no
2429         // available liquidity, causing any outbound payments routed over it to fail immediately.
2430         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1).0.contents.short_channel_id;
2431         let chan_2_id = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 989_000_000).0.contents.short_channel_id;
2432         let chan_3_id = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 989_000_000).0.contents.short_channel_id;
2433
2434         // Marshall data to send the payment
2435         let amt_msat = 10_000_000;
2436         let (_, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[1], amt_msat);
2437         #[cfg(feature = "std")]
2438         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2439         #[cfg(not(feature = "std"))]
2440         let payment_expiry_secs = 60 * 60;
2441         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2442         invoice_features.set_variable_length_onion_required();
2443         invoice_features.set_payment_secret_required();
2444         invoice_features.set_basic_mpp_optional();
2445         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2446                 .with_expiry_time(payment_expiry_secs as u64)
2447                 .with_bolt11_features(invoice_features).unwrap();
2448
2449         // Configure the initial send path
2450         let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2451         route_params.max_total_routing_fee_msat = None;
2452
2453         let send_route = Route {
2454                 paths: vec![
2455                         Path { hops: vec![RouteHop {
2456                                 pubkey: nodes[1].node.get_our_node_id(),
2457                                 node_features: nodes[1].node.node_features(),
2458                                 short_channel_id: chan_1_id,
2459                                 channel_features: nodes[1].node.channel_features(),
2460                                 fee_msat: amt_msat / 2,
2461                                 cltv_expiry_delta: 100,
2462                                 maybe_announced_channel: true,
2463                         }], blinded_tail: None },
2464                         Path { hops: vec![RouteHop {
2465                                 pubkey: nodes[1].node.get_our_node_id(),
2466                                 node_features: nodes[1].node.node_features(),
2467                                 short_channel_id: chan_2_id,
2468                                 channel_features: nodes[1].node.channel_features(),
2469                                 fee_msat: amt_msat / 2,
2470                                 cltv_expiry_delta: 100,
2471                                 maybe_announced_channel: true,
2472                         }], blinded_tail: None },
2473                 ],
2474                 route_params: Some(route_params.clone()),
2475         };
2476         nodes[0].router.expect_find_route(route_params.clone(), Ok(send_route));
2477
2478         // Configure the retry1 paths
2479         let mut payment_params = route_params.payment_params.clone();
2480         payment_params.previously_failed_channels.push(chan_2_id);
2481         let mut retry_1_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat / 2);
2482         retry_1_params.max_total_routing_fee_msat = None;
2483
2484         let retry_1_route = Route {
2485                 paths: vec![
2486                         Path { hops: vec![RouteHop {
2487                                 pubkey: nodes[1].node.get_our_node_id(),
2488                                 node_features: nodes[1].node.node_features(),
2489                                 short_channel_id: chan_1_id,
2490                                 channel_features: nodes[1].node.channel_features(),
2491                                 fee_msat: amt_msat / 4,
2492                                 cltv_expiry_delta: 100,
2493                                 maybe_announced_channel: true,
2494                         }], blinded_tail: None },
2495                         Path { hops: vec![RouteHop {
2496                                 pubkey: nodes[1].node.get_our_node_id(),
2497                                 node_features: nodes[1].node.node_features(),
2498                                 short_channel_id: chan_3_id,
2499                                 channel_features: nodes[1].node.channel_features(),
2500                                 fee_msat: amt_msat / 4,
2501                                 cltv_expiry_delta: 100,
2502                                 maybe_announced_channel: true,
2503                         }], blinded_tail: None },
2504                 ],
2505                 route_params: Some(retry_1_params.clone()),
2506         };
2507         nodes[0].router.expect_find_route(retry_1_params.clone(), Ok(retry_1_route));
2508
2509         // Configure the retry2 path
2510         let mut payment_params = retry_1_params.payment_params.clone();
2511         payment_params.previously_failed_channels.push(chan_3_id);
2512         let mut retry_2_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat / 4);
2513         retry_2_params.max_total_routing_fee_msat = None;
2514
2515         let retry_2_route = Route {
2516                 paths: vec![
2517                         Path { hops: vec![RouteHop {
2518                                 pubkey: nodes[1].node.get_our_node_id(),
2519                                 node_features: nodes[1].node.node_features(),
2520                                 short_channel_id: chan_1_id,
2521                                 channel_features: nodes[1].node.channel_features(),
2522                                 fee_msat: amt_msat / 4,
2523                                 cltv_expiry_delta: 100,
2524                                 maybe_announced_channel: true,
2525                         }], blinded_tail: None },
2526                 ],
2527                 route_params: Some(retry_2_params.clone()),
2528         };
2529         nodes[0].router.expect_find_route(retry_2_params, Ok(retry_2_route));
2530
2531         // Send a payment that will partially fail on send, then partially fail on retry, then succeed.
2532         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2533                 PaymentId(payment_hash.0), route_params, Retry::Attempts(3)).unwrap();
2534         let payment_failed_events = nodes[0].node.get_and_clear_pending_events();
2535         assert_eq!(payment_failed_events.len(), 2);
2536         match payment_failed_events[0] {
2537                 Event::PaymentPathFailed { .. } => {},
2538                 _ => panic!("Unexpected event"),
2539         }
2540         match payment_failed_events[1] {
2541                 Event::PaymentPathFailed { .. } => {},
2542                 _ => panic!("Unexpected event"),
2543         }
2544
2545         // Pass the first part of the payment along the path.
2546         check_added_monitors!(nodes[0], 1); // only one HTLC actually made it out
2547         let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
2548
2549         // Only one HTLC/channel update actually made it out
2550         assert_eq!(msg_events.len(), 1);
2551         let mut payment_event = SendEvent::from_event(msg_events.remove(0));
2552
2553         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
2554         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &payment_event.commitment_msg);
2555         check_added_monitors!(nodes[1], 1);
2556         let (bs_first_raa, bs_first_cs) = get_revoke_commit_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2557
2558         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_first_raa);
2559         check_added_monitors!(nodes[0], 1);
2560         let as_second_htlc_updates = SendEvent::from_node(&nodes[0]);
2561
2562         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_first_cs);
2563         check_added_monitors!(nodes[0], 1);
2564         let as_first_raa = get_event_msg!(nodes[0], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
2565
2566         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_first_raa);
2567         check_added_monitors!(nodes[1], 1);
2568
2569         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &as_second_htlc_updates.msgs[0]);
2570         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &as_second_htlc_updates.msgs[1]);
2571         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_second_htlc_updates.commitment_msg);
2572         check_added_monitors!(nodes[1], 1);
2573         let (bs_second_raa, bs_second_cs) = get_revoke_commit_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2574
2575         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
2576         check_added_monitors!(nodes[0], 1);
2577
2578         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_second_cs);
2579         check_added_monitors!(nodes[0], 1);
2580         let as_second_raa = get_event_msg!(nodes[0], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
2581
2582         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_second_raa);
2583         check_added_monitors!(nodes[1], 1);
2584
2585         expect_pending_htlcs_forwardable_ignore!(nodes[1]);
2586         nodes[1].node.process_pending_htlc_forwards();
2587         expect_payment_claimable!(nodes[1], payment_hash, payment_secret, amt_msat);
2588         nodes[1].node.claim_funds(payment_preimage);
2589         expect_payment_claimed!(nodes[1], payment_hash, amt_msat);
2590         let bs_claim_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2591         assert_eq!(bs_claim_update.update_fulfill_htlcs.len(), 1);
2592
2593         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_claim_update.update_fulfill_htlcs[0]);
2594         expect_payment_sent(&nodes[0], payment_preimage, None, false, false);
2595         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_claim_update.commitment_signed);
2596         check_added_monitors!(nodes[0], 1);
2597         let (as_third_raa, as_third_cs) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
2598
2599         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_third_raa);
2600         check_added_monitors!(nodes[1], 4);
2601         let bs_second_claim_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2602
2603         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_third_cs);
2604         check_added_monitors!(nodes[1], 1);
2605         let bs_third_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
2606
2607         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_third_raa);
2608         check_added_monitors!(nodes[0], 1);
2609         expect_payment_path_successful!(nodes[0]);
2610
2611         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_second_claim_update.update_fulfill_htlcs[0]);
2612         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &bs_second_claim_update.update_fulfill_htlcs[1]);
2613         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_second_claim_update.commitment_signed);
2614         check_added_monitors!(nodes[0], 1);
2615         let (as_fourth_raa, as_fourth_cs) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
2616
2617         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_fourth_raa);
2618         check_added_monitors!(nodes[1], 1);
2619
2620         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_fourth_cs);
2621         check_added_monitors!(nodes[1], 1);
2622         let bs_second_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
2623
2624         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
2625         check_added_monitors!(nodes[0], 1);
2626         let events = nodes[0].node.get_and_clear_pending_events();
2627         assert_eq!(events.len(), 2);
2628         if let Event::PaymentPathSuccessful { .. } = events[0] {} else { panic!(); }
2629         if let Event::PaymentPathSuccessful { .. } = events[1] {} else { panic!(); }
2630 }
2631
2632 #[test]
2633 fn auto_retry_zero_attempts_send_error() {
2634         let chanmon_cfgs = create_chanmon_cfgs(2);
2635         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
2636         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
2637         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
2638
2639         // Open a single channel that does not have sufficient liquidity for the payment we want to
2640         // send.
2641         let chan_id  = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 989_000_000).0.contents.short_channel_id;
2642
2643         // Marshall data to send the payment
2644         let amt_msat = 10_000_000;
2645         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[1], Some(amt_msat), None);
2646         #[cfg(feature = "std")]
2647         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2648         #[cfg(not(feature = "std"))]
2649         let payment_expiry_secs = 60 * 60;
2650         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2651         invoice_features.set_variable_length_onion_required();
2652         invoice_features.set_payment_secret_required();
2653         invoice_features.set_basic_mpp_optional();
2654         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2655                 .with_expiry_time(payment_expiry_secs as u64)
2656                 .with_bolt11_features(invoice_features).unwrap();
2657         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2658
2659         // Override the route search to return a route, rather than failing at the route-finding step.
2660         let send_route = Route {
2661                 paths: vec![
2662                         Path { hops: vec![RouteHop {
2663                                 pubkey: nodes[1].node.get_our_node_id(),
2664                                 node_features: nodes[1].node.node_features(),
2665                                 short_channel_id: chan_id,
2666                                 channel_features: nodes[1].node.channel_features(),
2667                                 fee_msat: amt_msat,
2668                                 cltv_expiry_delta: 100,
2669                                 maybe_announced_channel: true,
2670                         }], blinded_tail: None },
2671                 ],
2672                 route_params: Some(route_params.clone()),
2673         };
2674         nodes[0].router.expect_find_route(route_params.clone(), Ok(send_route));
2675
2676         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2677                 PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
2678         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
2679         let events = nodes[0].node.get_and_clear_pending_events();
2680         assert_eq!(events.len(), 2);
2681         if let Event::PaymentPathFailed { .. } = events[0] { } else { panic!(); }
2682         if let Event::PaymentFailed { .. } = events[1] { } else { panic!(); }
2683         check_added_monitors!(nodes[0], 0);
2684 }
2685
2686 #[test]
2687 fn fails_paying_after_rejected_by_payee() {
2688         let chanmon_cfgs = create_chanmon_cfgs(2);
2689         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
2690         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
2691         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
2692
2693         create_announced_chan_between_nodes(&nodes, 0, 1).0.contents.short_channel_id;
2694
2695         // Marshall data to send the payment
2696         let amt_msat = 20_000;
2697         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[1], amt_msat);
2698         #[cfg(feature = "std")]
2699         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2700         #[cfg(not(feature = "std"))]
2701         let payment_expiry_secs = 60 * 60;
2702         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2703         invoice_features.set_variable_length_onion_required();
2704         invoice_features.set_payment_secret_required();
2705         invoice_features.set_basic_mpp_optional();
2706         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2707                 .with_expiry_time(payment_expiry_secs as u64)
2708                 .with_bolt11_features(invoice_features).unwrap();
2709         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2710
2711         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2712                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2713         check_added_monitors!(nodes[0], 1);
2714         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
2715         assert_eq!(events.len(), 1);
2716         let mut payment_event = SendEvent::from_event(events.pop().unwrap());
2717         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
2718         check_added_monitors!(nodes[1], 0);
2719         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false);
2720         expect_pending_htlcs_forwardable!(nodes[1]);
2721         expect_payment_claimable!(&nodes[1], payment_hash, payment_secret, amt_msat);
2722
2723         nodes[1].node.fail_htlc_backwards(&payment_hash);
2724         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], [HTLCDestination::FailedPayment { payment_hash }]);
2725         pass_failed_payment_back(&nodes[0], &[&[&nodes[1]]], false, payment_hash, PaymentFailureReason::RecipientRejected);
2726 }
2727
2728 #[test]
2729 fn retry_multi_path_single_failed_payment() {
2730         // Tests that we can/will retry after a single path of an MPP payment failed immediately
2731         let chanmon_cfgs = create_chanmon_cfgs(2);
2732         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
2733         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None, None]);
2734         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
2735
2736         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
2737         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
2738
2739         let amt_msat = 100_010_000;
2740
2741         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[1], amt_msat);
2742         #[cfg(feature = "std")]
2743         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2744         #[cfg(not(feature = "std"))]
2745         let payment_expiry_secs = 60 * 60;
2746         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2747         invoice_features.set_variable_length_onion_required();
2748         invoice_features.set_payment_secret_required();
2749         invoice_features.set_basic_mpp_optional();
2750         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2751                 .with_expiry_time(payment_expiry_secs as u64)
2752                 .with_bolt11_features(invoice_features).unwrap();
2753         let mut route_params = RouteParameters::from_payment_params_and_value(
2754                 payment_params.clone(), amt_msat);
2755         route_params.max_total_routing_fee_msat = None;
2756
2757         let chans = nodes[0].node.list_usable_channels();
2758         let mut route = Route {
2759                 paths: vec![
2760                         Path { hops: vec![RouteHop {
2761                                 pubkey: nodes[1].node.get_our_node_id(),
2762                                 node_features: nodes[1].node.node_features(),
2763                                 short_channel_id: chans[0].short_channel_id.unwrap(),
2764                                 channel_features: nodes[1].node.channel_features(),
2765                                 fee_msat: 10_000,
2766                                 cltv_expiry_delta: 100,
2767                                 maybe_announced_channel: true,
2768                         }], blinded_tail: None },
2769                         Path { hops: vec![RouteHop {
2770                                 pubkey: nodes[1].node.get_our_node_id(),
2771                                 node_features: nodes[1].node.node_features(),
2772                                 short_channel_id: chans[1].short_channel_id.unwrap(),
2773                                 channel_features: nodes[1].node.channel_features(),
2774                                 fee_msat: 100_000_001, // Our default max-HTLC-value is 10% of the channel value, which this is one more than
2775                                 cltv_expiry_delta: 100,
2776                                 maybe_announced_channel: true,
2777                         }], blinded_tail: None },
2778                 ],
2779                 route_params: Some(route_params.clone()),
2780         };
2781         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
2782         // On retry, split the payment across both channels.
2783         route.paths[0].hops[0].fee_msat = 50_000_001;
2784         route.paths[1].hops[0].fee_msat = 50_000_000;
2785         let mut pay_params = route.route_params.clone().unwrap().payment_params;
2786         pay_params.previously_failed_channels.push(chans[1].short_channel_id.unwrap());
2787
2788         let mut retry_params = RouteParameters::from_payment_params_and_value(pay_params, 100_000_000);
2789         retry_params.max_total_routing_fee_msat = None;
2790         route.route_params = Some(retry_params.clone());
2791         nodes[0].router.expect_find_route(retry_params, Ok(route.clone()));
2792
2793         {
2794                 let scorer = chanmon_cfgs[0].scorer.read().unwrap();
2795                 // The initial send attempt, 2 paths
2796                 scorer.expect_usage(chans[0].short_channel_id.unwrap(), ChannelUsage { amount_msat: 10_000, inflight_htlc_msat: 0, effective_capacity: EffectiveCapacity::Unknown });
2797                 scorer.expect_usage(chans[1].short_channel_id.unwrap(), ChannelUsage { amount_msat: 100_000_001, inflight_htlc_msat: 0, effective_capacity: EffectiveCapacity::Unknown });
2798                 // The retry, 2 paths. Ensure that the in-flight HTLC amount is factored in.
2799                 scorer.expect_usage(chans[0].short_channel_id.unwrap(), ChannelUsage { amount_msat: 50_000_001, inflight_htlc_msat: 10_000, effective_capacity: EffectiveCapacity::Unknown });
2800                 scorer.expect_usage(chans[1].short_channel_id.unwrap(), ChannelUsage { amount_msat: 50_000_000, inflight_htlc_msat: 0, effective_capacity: EffectiveCapacity::Unknown });
2801         }
2802
2803         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2804                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2805         let events = nodes[0].node.get_and_clear_pending_events();
2806         assert_eq!(events.len(), 1);
2807         match events[0] {
2808                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently: false,
2809                         failure: PathFailure::InitialSend { err: APIError::ChannelUnavailable { .. }},
2810                         short_channel_id: Some(expected_scid), .. } =>
2811                 {
2812                         assert_eq!(payment_hash, ev_payment_hash);
2813                         assert_eq!(expected_scid, route.paths[1].hops[0].short_channel_id);
2814                 },
2815                 _ => panic!("Unexpected event"),
2816         }
2817         let htlc_msgs = nodes[0].node.get_and_clear_pending_msg_events();
2818         assert_eq!(htlc_msgs.len(), 2);
2819         check_added_monitors!(nodes[0], 2);
2820 }
2821
2822 #[test]
2823 fn immediate_retry_on_failure() {
2824         // Tests that we can/will retry immediately after a failure
2825         let chanmon_cfgs = create_chanmon_cfgs(2);
2826         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
2827         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None, None]);
2828         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
2829
2830         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
2831         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
2832
2833         let amt_msat = 100_000_001;
2834         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[1], amt_msat);
2835         #[cfg(feature = "std")]
2836         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2837         #[cfg(not(feature = "std"))]
2838         let payment_expiry_secs = 60 * 60;
2839         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2840         invoice_features.set_variable_length_onion_required();
2841         invoice_features.set_payment_secret_required();
2842         invoice_features.set_basic_mpp_optional();
2843         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2844                 .with_expiry_time(payment_expiry_secs as u64)
2845                 .with_bolt11_features(invoice_features).unwrap();
2846         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2847
2848         let chans = nodes[0].node.list_usable_channels();
2849         let mut route = Route {
2850                 paths: vec![
2851                         Path { hops: vec![RouteHop {
2852                                 pubkey: nodes[1].node.get_our_node_id(),
2853                                 node_features: nodes[1].node.node_features(),
2854                                 short_channel_id: chans[0].short_channel_id.unwrap(),
2855                                 channel_features: nodes[1].node.channel_features(),
2856                                 fee_msat: 100_000_001, // Our default max-HTLC-value is 10% of the channel value, which this is one more than
2857                                 cltv_expiry_delta: 100,
2858                                 maybe_announced_channel: true,
2859                         }], blinded_tail: None },
2860                 ],
2861                 route_params: Some(route_params.clone()),
2862         };
2863         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
2864         // On retry, split the payment across both channels.
2865         route.paths.push(route.paths[0].clone());
2866         route.paths[0].hops[0].short_channel_id = chans[1].short_channel_id.unwrap();
2867         route.paths[0].hops[0].fee_msat = 50_000_000;
2868         route.paths[1].hops[0].fee_msat = 50_000_001;
2869         let mut pay_params = route_params.payment_params.clone();
2870         pay_params.previously_failed_channels.push(chans[0].short_channel_id.unwrap());
2871         let retry_params = RouteParameters::from_payment_params_and_value(pay_params, amt_msat);
2872         route.route_params = Some(retry_params.clone());
2873         nodes[0].router.expect_find_route(retry_params, Ok(route.clone()));
2874
2875         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2876                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2877         let events = nodes[0].node.get_and_clear_pending_events();
2878         assert_eq!(events.len(), 1);
2879         match events[0] {
2880                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently: false,
2881                         failure: PathFailure::InitialSend { err: APIError::ChannelUnavailable { .. }},
2882                         short_channel_id: Some(expected_scid), .. } =>
2883                 {
2884                         assert_eq!(payment_hash, ev_payment_hash);
2885                         assert_eq!(expected_scid, route.paths[1].hops[0].short_channel_id);
2886                 },
2887                 _ => panic!("Unexpected event"),
2888         }
2889         let htlc_msgs = nodes[0].node.get_and_clear_pending_msg_events();
2890         assert_eq!(htlc_msgs.len(), 2);
2891         check_added_monitors!(nodes[0], 2);
2892 }
2893
2894 #[test]
2895 fn no_extra_retries_on_back_to_back_fail() {
2896         // In a previous release, we had a race where we may exceed the payment retry count if we
2897         // get two failures in a row with the second indicating that all paths had failed (this field,
2898         // `all_paths_failed`, has since been removed).
2899         // Generally, when we give up trying to retry a payment, we don't know for sure what the
2900         // current state of the ChannelManager event queue is. Specifically, we cannot be sure that
2901         // there are not multiple additional `PaymentPathFailed` or even `PaymentSent` events
2902         // pending which we will see later. Thus, when we previously removed the retry tracking map
2903         // entry after a `all_paths_failed` `PaymentPathFailed` event, we may have dropped the
2904         // retry entry even though more events for the same payment were still pending. This led to
2905         // us retrying a payment again even though we'd already given up on it.
2906         //
2907         // We now have a separate event - `PaymentFailed` which indicates no HTLCs remain and which
2908         // is used to remove the payment retry counter entries instead. This tests for the specific
2909         // excess-retry case while also testing `PaymentFailed` generation.
2910
2911         let chanmon_cfgs = create_chanmon_cfgs(3);
2912         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
2913         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
2914         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
2915
2916         let chan_1_scid = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0).0.contents.short_channel_id;
2917         let chan_2_scid = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 10_000_000, 0).0.contents.short_channel_id;
2918
2919         let amt_msat = 200_000_000;
2920         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[1], amt_msat);
2921         #[cfg(feature = "std")]
2922         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
2923         #[cfg(not(feature = "std"))]
2924         let payment_expiry_secs = 60 * 60;
2925         let mut invoice_features = Bolt11InvoiceFeatures::empty();
2926         invoice_features.set_variable_length_onion_required();
2927         invoice_features.set_payment_secret_required();
2928         invoice_features.set_basic_mpp_optional();
2929         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
2930                 .with_expiry_time(payment_expiry_secs as u64)
2931                 .with_bolt11_features(invoice_features).unwrap();
2932         let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
2933         route_params.max_total_routing_fee_msat = None;
2934
2935         let mut route = Route {
2936                 paths: vec![
2937                         Path { hops: vec![RouteHop {
2938                                 pubkey: nodes[1].node.get_our_node_id(),
2939                                 node_features: nodes[1].node.node_features(),
2940                                 short_channel_id: chan_1_scid,
2941                                 channel_features: nodes[1].node.channel_features(),
2942                                 fee_msat: 0, // nodes[1] will fail the payment as we don't pay its fee
2943                                 cltv_expiry_delta: 100,
2944                                 maybe_announced_channel: true,
2945                         }, RouteHop {
2946                                 pubkey: nodes[2].node.get_our_node_id(),
2947                                 node_features: nodes[2].node.node_features(),
2948                                 short_channel_id: chan_2_scid,
2949                                 channel_features: nodes[2].node.channel_features(),
2950                                 fee_msat: 100_000_000,
2951                                 cltv_expiry_delta: 100,
2952                                 maybe_announced_channel: true,
2953                         }], blinded_tail: None },
2954                         Path { hops: vec![RouteHop {
2955                                 pubkey: nodes[1].node.get_our_node_id(),
2956                                 node_features: nodes[1].node.node_features(),
2957                                 short_channel_id: chan_1_scid,
2958                                 channel_features: nodes[1].node.channel_features(),
2959                                 fee_msat: 0, // nodes[1] will fail the payment as we don't pay its fee
2960                                 cltv_expiry_delta: 100,
2961                                 maybe_announced_channel: true,
2962                         }, RouteHop {
2963                                 pubkey: nodes[2].node.get_our_node_id(),
2964                                 node_features: nodes[2].node.node_features(),
2965                                 short_channel_id: chan_2_scid,
2966                                 channel_features: nodes[2].node.channel_features(),
2967                                 fee_msat: 100_000_000,
2968                                 cltv_expiry_delta: 100,
2969                                 maybe_announced_channel: true,
2970                         }], blinded_tail: None }
2971                 ],
2972                 route_params: Some(route_params.clone()),
2973         };
2974         route.route_params.as_mut().unwrap().max_total_routing_fee_msat = None;
2975         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
2976         let mut second_payment_params = route_params.payment_params.clone();
2977         second_payment_params.previously_failed_channels = vec![chan_2_scid, chan_2_scid];
2978         // On retry, we'll only return one path
2979         route.paths.remove(1);
2980         route.paths[0].hops[1].fee_msat = amt_msat;
2981         let mut retry_params = RouteParameters::from_payment_params_and_value(second_payment_params, amt_msat);
2982         retry_params.max_total_routing_fee_msat = None;
2983         route.route_params = Some(retry_params.clone());
2984         nodes[0].router.expect_find_route(retry_params, Ok(route.clone()));
2985
2986         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
2987                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
2988         let htlc_updates = SendEvent::from_node(&nodes[0]);
2989         check_added_monitors!(nodes[0], 1);
2990         assert_eq!(htlc_updates.msgs.len(), 1);
2991
2992         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &htlc_updates.msgs[0]);
2993         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &htlc_updates.commitment_msg);
2994         check_added_monitors!(nodes[1], 1);
2995         let (bs_first_raa, bs_first_cs) = get_revoke_commit_msgs!(nodes[1], nodes[0].node.get_our_node_id());
2996
2997         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_first_raa);
2998         check_added_monitors!(nodes[0], 1);
2999         let second_htlc_updates = SendEvent::from_node(&nodes[0]);
3000
3001         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_first_cs);
3002         check_added_monitors!(nodes[0], 1);
3003         let as_first_raa = get_event_msg!(nodes[0], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
3004
3005         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &second_htlc_updates.msgs[0]);
3006         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &second_htlc_updates.commitment_msg);
3007         check_added_monitors!(nodes[1], 1);
3008         let bs_second_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
3009
3010         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_first_raa);
3011         check_added_monitors!(nodes[1], 1);
3012         let bs_fail_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3013
3014         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
3015         check_added_monitors!(nodes[0], 1);
3016
3017         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &bs_fail_update.update_fail_htlcs[0]);
3018         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_fail_update.commitment_signed);
3019         check_added_monitors!(nodes[0], 1);
3020         let (as_second_raa, as_third_cs) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
3021
3022         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_second_raa);
3023         check_added_monitors!(nodes[1], 1);
3024         let bs_second_fail_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3025
3026         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_third_cs);
3027         check_added_monitors!(nodes[1], 1);
3028         let bs_third_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
3029
3030         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &bs_second_fail_update.update_fail_htlcs[0]);
3031         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_second_fail_update.commitment_signed);
3032         check_added_monitors!(nodes[0], 1);
3033
3034         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_third_raa);
3035         check_added_monitors!(nodes[0], 1);
3036         let (as_third_raa, as_fourth_cs) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
3037
3038         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_third_raa);
3039         check_added_monitors!(nodes[1], 1);
3040         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_fourth_cs);
3041         check_added_monitors!(nodes[1], 1);
3042         let bs_fourth_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
3043
3044         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_fourth_raa);
3045         check_added_monitors!(nodes[0], 1);
3046
3047         // At this point A has sent two HTLCs which both failed due to lack of fee. It now has two
3048         // pending `PaymentPathFailed` events, one with `all_paths_failed` unset, and the second
3049         // with it set.
3050         //
3051         // Previously, we retried payments in an event consumer, which would retry each
3052         // `PaymentPathFailed` individually. In that setup, we had retried the payment in response to
3053         // the first `PaymentPathFailed`, then seen the second `PaymentPathFailed` with
3054         // `all_paths_failed` set and assumed the payment was completely failed. We ultimately fixed it
3055         // by adding the `PaymentFailed` event.
3056         //
3057         // Because we now retry payments as a batch, we simply return a single-path route in the
3058         // second, batched, request, have that fail, ensure the payment was abandoned.
3059         let mut events = nodes[0].node.get_and_clear_pending_events();
3060         assert_eq!(events.len(), 3);
3061         match events[0] {
3062                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
3063                         assert_eq!(payment_hash, ev_payment_hash);
3064                         assert_eq!(payment_failed_permanently, false);
3065                 },
3066                 _ => panic!("Unexpected event"),
3067         }
3068         match events[1] {
3069                 Event::PendingHTLCsForwardable { .. } => {},
3070                 _ => panic!("Unexpected event"),
3071         }
3072         match events[2] {
3073                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
3074                         assert_eq!(payment_hash, ev_payment_hash);
3075                         assert_eq!(payment_failed_permanently, false);
3076                 },
3077                 _ => panic!("Unexpected event"),
3078         }
3079
3080         nodes[0].node.process_pending_htlc_forwards();
3081         let retry_htlc_updates = SendEvent::from_node(&nodes[0]);
3082         check_added_monitors!(nodes[0], 1);
3083
3084         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &retry_htlc_updates.msgs[0]);
3085         commitment_signed_dance!(nodes[1], nodes[0], &retry_htlc_updates.commitment_msg, false, true);
3086         let bs_fail_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3087         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &bs_fail_update.update_fail_htlcs[0]);
3088         commitment_signed_dance!(nodes[0], nodes[1], &bs_fail_update.commitment_signed, false, true);
3089
3090         let mut events = nodes[0].node.get_and_clear_pending_events();
3091         assert_eq!(events.len(), 2);
3092         match events[0] {
3093                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
3094                         assert_eq!(payment_hash, ev_payment_hash);
3095                         assert_eq!(payment_failed_permanently, false);
3096                 },
3097                 _ => panic!("Unexpected event"),
3098         }
3099         match events[1] {
3100                 Event::PaymentFailed { payment_hash: ref ev_payment_hash, payment_id: ref ev_payment_id, reason: ref ev_reason } => {
3101                         assert_eq!(payment_hash, *ev_payment_hash);
3102                         assert_eq!(PaymentId(payment_hash.0), *ev_payment_id);
3103                         assert_eq!(PaymentFailureReason::RetriesExhausted, ev_reason.unwrap());
3104                 },
3105                 _ => panic!("Unexpected event"),
3106         }
3107 }
3108
3109 #[test]
3110 fn test_simple_partial_retry() {
3111         // In the first version of the in-`ChannelManager` payment retries, retries were sent for the
3112         // full amount of the payment, rather than only the missing amount. Here we simply test for
3113         // this by sending a payment with two parts, failing one, and retrying the second. Note that
3114         // `TestRouter` will check that the `RouteParameters` (which contain the amount) matches the
3115         // request.
3116         let chanmon_cfgs = create_chanmon_cfgs(3);
3117         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
3118         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
3119         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
3120
3121         let chan_1_scid = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0).0.contents.short_channel_id;
3122         let chan_2_scid = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 10_000_000, 0).0.contents.short_channel_id;
3123
3124         let amt_msat = 200_000_000;
3125         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[2], amt_msat);
3126         #[cfg(feature = "std")]
3127         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
3128         #[cfg(not(feature = "std"))]
3129         let payment_expiry_secs = 60 * 60;
3130         let mut invoice_features = Bolt11InvoiceFeatures::empty();
3131         invoice_features.set_variable_length_onion_required();
3132         invoice_features.set_payment_secret_required();
3133         invoice_features.set_basic_mpp_optional();
3134         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
3135                 .with_expiry_time(payment_expiry_secs as u64)
3136                 .with_bolt11_features(invoice_features).unwrap();
3137         let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
3138         route_params.max_total_routing_fee_msat = None;
3139
3140         let mut route = Route {
3141                 paths: vec![
3142                         Path { hops: vec![RouteHop {
3143                                 pubkey: nodes[1].node.get_our_node_id(),
3144                                 node_features: nodes[1].node.node_features(),
3145                                 short_channel_id: chan_1_scid,
3146                                 channel_features: nodes[1].node.channel_features(),
3147                                 fee_msat: 0, // nodes[1] will fail the payment as we don't pay its fee
3148                                 cltv_expiry_delta: 100,
3149                                 maybe_announced_channel: true,
3150                         }, RouteHop {
3151                                 pubkey: nodes[2].node.get_our_node_id(),
3152                                 node_features: nodes[2].node.node_features(),
3153                                 short_channel_id: chan_2_scid,
3154                                 channel_features: nodes[2].node.channel_features(),
3155                                 fee_msat: 100_000_000,
3156                                 cltv_expiry_delta: 100,
3157                                 maybe_announced_channel: true,
3158                         }], blinded_tail: None },
3159                         Path { hops: vec![RouteHop {
3160                                 pubkey: nodes[1].node.get_our_node_id(),
3161                                 node_features: nodes[1].node.node_features(),
3162                                 short_channel_id: chan_1_scid,
3163                                 channel_features: nodes[1].node.channel_features(),
3164                                 fee_msat: 100_000,
3165                                 cltv_expiry_delta: 100,
3166                                 maybe_announced_channel: true,
3167                         }, RouteHop {
3168                                 pubkey: nodes[2].node.get_our_node_id(),
3169                                 node_features: nodes[2].node.node_features(),
3170                                 short_channel_id: chan_2_scid,
3171                                 channel_features: nodes[2].node.channel_features(),
3172                                 fee_msat: 100_000_000,
3173                                 cltv_expiry_delta: 100,
3174                                 maybe_announced_channel: true,
3175                         }], blinded_tail: None }
3176                 ],
3177                 route_params: Some(route_params.clone()),
3178         };
3179
3180         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
3181
3182         let mut second_payment_params = route_params.payment_params.clone();
3183         second_payment_params.previously_failed_channels = vec![chan_2_scid];
3184         // On retry, we'll only be asked for one path (or 100k sats)
3185         route.paths.remove(0);
3186         let mut retry_params = RouteParameters::from_payment_params_and_value(second_payment_params, amt_msat / 2);
3187         retry_params.max_total_routing_fee_msat = None;
3188         route.route_params = Some(retry_params.clone());
3189         nodes[0].router.expect_find_route(retry_params, Ok(route.clone()));
3190
3191         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
3192                 PaymentId(payment_hash.0), route_params, Retry::Attempts(1)).unwrap();
3193         let htlc_updates = SendEvent::from_node(&nodes[0]);
3194         check_added_monitors!(nodes[0], 1);
3195         assert_eq!(htlc_updates.msgs.len(), 1);
3196
3197         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &htlc_updates.msgs[0]);
3198         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &htlc_updates.commitment_msg);
3199         check_added_monitors!(nodes[1], 1);
3200         let (bs_first_raa, bs_first_cs) = get_revoke_commit_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3201
3202         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_first_raa);
3203         check_added_monitors!(nodes[0], 1);
3204         let second_htlc_updates = SendEvent::from_node(&nodes[0]);
3205
3206         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_first_cs);
3207         check_added_monitors!(nodes[0], 1);
3208         let as_first_raa = get_event_msg!(nodes[0], MessageSendEvent::SendRevokeAndACK, nodes[1].node.get_our_node_id());
3209
3210         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &second_htlc_updates.msgs[0]);
3211         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &second_htlc_updates.commitment_msg);
3212         check_added_monitors!(nodes[1], 1);
3213         let bs_second_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
3214
3215         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_first_raa);
3216         check_added_monitors!(nodes[1], 1);
3217         let bs_fail_update = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3218
3219         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_second_raa);
3220         check_added_monitors!(nodes[0], 1);
3221
3222         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &bs_fail_update.update_fail_htlcs[0]);
3223         nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &bs_fail_update.commitment_signed);
3224         check_added_monitors!(nodes[0], 1);
3225         let (as_second_raa, as_third_cs) = get_revoke_commit_msgs!(nodes[0], nodes[1].node.get_our_node_id());
3226
3227         nodes[1].node.handle_revoke_and_ack(&nodes[0].node.get_our_node_id(), &as_second_raa);
3228         check_added_monitors!(nodes[1], 1);
3229
3230         nodes[1].node.handle_commitment_signed(&nodes[0].node.get_our_node_id(), &as_third_cs);
3231         check_added_monitors!(nodes[1], 1);
3232
3233         let bs_third_raa = get_event_msg!(nodes[1], MessageSendEvent::SendRevokeAndACK, nodes[0].node.get_our_node_id());
3234
3235         nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &bs_third_raa);
3236         check_added_monitors!(nodes[0], 1);
3237
3238         let mut events = nodes[0].node.get_and_clear_pending_events();
3239         assert_eq!(events.len(), 2);
3240         match events[0] {
3241                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
3242                         assert_eq!(payment_hash, ev_payment_hash);
3243                         assert_eq!(payment_failed_permanently, false);
3244                 },
3245                 _ => panic!("Unexpected event"),
3246         }
3247         match events[1] {
3248                 Event::PendingHTLCsForwardable { .. } => {},
3249                 _ => panic!("Unexpected event"),
3250         }
3251
3252         nodes[0].node.process_pending_htlc_forwards();
3253         let retry_htlc_updates = SendEvent::from_node(&nodes[0]);
3254         check_added_monitors!(nodes[0], 1);
3255
3256         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &retry_htlc_updates.msgs[0]);
3257         commitment_signed_dance!(nodes[1], nodes[0], &retry_htlc_updates.commitment_msg, false, true);
3258
3259         expect_pending_htlcs_forwardable!(nodes[1]);
3260         check_added_monitors!(nodes[1], 1);
3261
3262         let bs_forward_update = get_htlc_update_msgs!(nodes[1], nodes[2].node.get_our_node_id());
3263         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &bs_forward_update.update_add_htlcs[0]);
3264         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &bs_forward_update.update_add_htlcs[1]);
3265         commitment_signed_dance!(nodes[2], nodes[1], &bs_forward_update.commitment_signed, false);
3266
3267         expect_pending_htlcs_forwardable!(nodes[2]);
3268         expect_payment_claimable!(nodes[2], payment_hash, payment_secret, amt_msat);
3269 }
3270
3271 #[test]
3272 #[cfg(feature = "std")]
3273 fn test_threaded_payment_retries() {
3274         // In the first version of the in-`ChannelManager` payment retries, retries weren't limited to
3275         // a single thread and would happily let multiple threads run retries at the same time. Because
3276         // retries are done by first calculating the amount we need to retry, then dropping the
3277         // relevant lock, then actually sending, we would happily let multiple threads retry the same
3278         // amount at the same time, overpaying our original HTLC!
3279         let chanmon_cfgs = create_chanmon_cfgs(4);
3280         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
3281         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
3282         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
3283
3284         // There is one mitigating guardrail when retrying payments - we can never over-pay by more
3285         // than 10% of the original value. Thus, we want all our retries to be below that. In order to
3286         // keep things simple, we route one HTLC for 0.1% of the payment over channel 1 and the rest
3287         // out over channel 3+4. This will let us ignore 99% of the payment value and deal with only
3288         // our channel.
3289         let chan_1_scid = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 10_000_000, 0).0.contents.short_channel_id;
3290         create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 10_000_000, 0);
3291         let chan_3_scid = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 10_000_000, 0).0.contents.short_channel_id;
3292         let chan_4_scid = create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 10_000_000, 0).0.contents.short_channel_id;
3293
3294         let amt_msat = 100_000_000;
3295         let (_, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[2], amt_msat);
3296         #[cfg(feature = "std")]
3297         let payment_expiry_secs = SystemTime::UNIX_EPOCH.elapsed().unwrap().as_secs() + 60 * 60;
3298         #[cfg(not(feature = "std"))]
3299         let payment_expiry_secs = 60 * 60;
3300         let mut invoice_features = Bolt11InvoiceFeatures::empty();
3301         invoice_features.set_variable_length_onion_required();
3302         invoice_features.set_payment_secret_required();
3303         invoice_features.set_basic_mpp_optional();
3304         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id(), TEST_FINAL_CLTV)
3305                 .with_expiry_time(payment_expiry_secs as u64)
3306                 .with_bolt11_features(invoice_features).unwrap();
3307         let mut route_params = RouteParameters {
3308                 payment_params, final_value_msat: amt_msat, max_total_routing_fee_msat: Some(500_000),
3309         };
3310
3311         let mut route = Route {
3312                 paths: vec![
3313                         Path { hops: vec![RouteHop {
3314                                 pubkey: nodes[1].node.get_our_node_id(),
3315                                 node_features: nodes[1].node.node_features(),
3316                                 short_channel_id: chan_1_scid,
3317                                 channel_features: nodes[1].node.channel_features(),
3318                                 fee_msat: 0,
3319                                 cltv_expiry_delta: 100,
3320                                 maybe_announced_channel: true,
3321                         }, RouteHop {
3322                                 pubkey: nodes[3].node.get_our_node_id(),
3323                                 node_features: nodes[2].node.node_features(),
3324                                 short_channel_id: 42, // Set a random SCID which nodes[1] will fail as unknown
3325                                 channel_features: nodes[2].node.channel_features(),
3326                                 fee_msat: amt_msat / 1000,
3327                                 cltv_expiry_delta: 100,
3328                                 maybe_announced_channel: true,
3329                         }], blinded_tail: None },
3330                         Path { hops: vec![RouteHop {
3331                                 pubkey: nodes[2].node.get_our_node_id(),
3332                                 node_features: nodes[2].node.node_features(),
3333                                 short_channel_id: chan_3_scid,
3334                                 channel_features: nodes[2].node.channel_features(),
3335                                 fee_msat: 100_000,
3336                                 cltv_expiry_delta: 100,
3337                                 maybe_announced_channel: true,
3338                         }, RouteHop {
3339                                 pubkey: nodes[3].node.get_our_node_id(),
3340                                 node_features: nodes[3].node.node_features(),
3341                                 short_channel_id: chan_4_scid,
3342                                 channel_features: nodes[3].node.channel_features(),
3343                                 fee_msat: amt_msat - amt_msat / 1000,
3344                                 cltv_expiry_delta: 100,
3345                                 maybe_announced_channel: true,
3346                         }], blinded_tail: None }
3347                 ],
3348                 route_params: Some(route_params.clone()),
3349         };
3350         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
3351
3352         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
3353                 PaymentId(payment_hash.0), route_params.clone(), Retry::Attempts(0xdeadbeef)).unwrap();
3354         check_added_monitors!(nodes[0], 2);
3355         let mut send_msg_events = nodes[0].node.get_and_clear_pending_msg_events();
3356         assert_eq!(send_msg_events.len(), 2);
3357         send_msg_events.retain(|msg|
3358                 if let MessageSendEvent::UpdateHTLCs { node_id, .. } = msg {
3359                         // Drop the commitment update for nodes[2], we can just let that one sit pending
3360                         // forever.
3361                         *node_id == nodes[1].node.get_our_node_id()
3362                 } else { panic!(); }
3363         );
3364
3365         // from here on out, the retry `RouteParameters` amount will be amt/1000
3366         route_params.final_value_msat /= 1000;
3367         route.route_params = Some(route_params.clone());
3368         route.paths.pop();
3369
3370         let end_time = Instant::now() + Duration::from_secs(1);
3371         macro_rules! thread_body { () => { {
3372                 // We really want std::thread::scope, but its not stable until 1.63. Until then, we get unsafe.
3373                 let node_ref = NodePtr::from_node(&nodes[0]);
3374                 move || {
3375                         let _ = &node_ref;
3376                         let node_a = unsafe { &*node_ref.0 };
3377                         while Instant::now() < end_time {
3378                                 node_a.node.get_and_clear_pending_events(); // wipe the PendingHTLCsForwardable
3379                                 // Ignore if we have any pending events, just always pretend we just got a
3380                                 // PendingHTLCsForwardable
3381                                 node_a.node.process_pending_htlc_forwards();
3382                         }
3383                 }
3384         } } }
3385         let mut threads = Vec::new();
3386         for _ in 0..16 { threads.push(std::thread::spawn(thread_body!())); }
3387
3388         // Back in the main thread, poll pending messages and make sure that we never have more than
3389         // one HTLC pending at a time. Note that the commitment_signed_dance will fail horribly if
3390         // there are HTLC messages shoved in while its running. This allows us to test that we never
3391         // generate an additional update_add_htlc until we've fully failed the first.
3392         let mut previously_failed_channels = Vec::new();
3393         loop {
3394                 assert_eq!(send_msg_events.len(), 1);
3395                 let send_event = SendEvent::from_event(send_msg_events.pop().unwrap());
3396                 assert_eq!(send_event.msgs.len(), 1);
3397
3398                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
3399                 commitment_signed_dance!(nodes[1], nodes[0], send_event.commitment_msg, false, true);
3400
3401                 // Note that we only push one route into `expect_find_route` at a time, because that's all
3402                 // the retries (should) need. If the bug is reintroduced "real" routes may be selected, but
3403                 // we should still ultimately fail for the same reason - because we're trying to send too
3404                 // many HTLCs at once.
3405                 let mut new_route_params = route_params.clone();
3406                 previously_failed_channels.push(route.paths[0].hops[1].short_channel_id);
3407                 new_route_params.payment_params.previously_failed_channels = previously_failed_channels.clone();
3408                 new_route_params.max_total_routing_fee_msat.as_mut().map(|m| *m -= 100_000);
3409                 route.paths[0].hops[1].short_channel_id += 1;
3410                 route.route_params = Some(new_route_params.clone());
3411                 nodes[0].router.expect_find_route(new_route_params, Ok(route.clone()));
3412
3413                 let bs_fail_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3414                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &bs_fail_updates.update_fail_htlcs[0]);
3415                 // The "normal" commitment_signed_dance delivers the final RAA and then calls
3416                 // `check_added_monitors` to ensure only the one RAA-generated monitor update was created.
3417                 // This races with our other threads which may generate an add-HTLCs commitment update via
3418                 // `process_pending_htlc_forwards`. Instead, we defer the monitor update check until after
3419                 // *we've* called `process_pending_htlc_forwards` when its guaranteed to have two updates.
3420                 let last_raa = commitment_signed_dance!(nodes[0], nodes[1], bs_fail_updates.commitment_signed, false, true, false, true);
3421                 nodes[0].node.handle_revoke_and_ack(&nodes[1].node.get_our_node_id(), &last_raa);
3422
3423                 let cur_time = Instant::now();
3424                 if cur_time > end_time {
3425                         for thread in threads.drain(..) { thread.join().unwrap(); }
3426                 }
3427
3428                 // Make sure we have some events to handle when we go around...
3429                 nodes[0].node.get_and_clear_pending_events(); // wipe the PendingHTLCsForwardable
3430                 nodes[0].node.process_pending_htlc_forwards();
3431                 send_msg_events = nodes[0].node.get_and_clear_pending_msg_events();
3432                 check_added_monitors!(nodes[0], 2);
3433
3434                 if cur_time > end_time {
3435                         break;
3436                 }
3437         }
3438 }
3439
3440 fn do_no_missing_sent_on_reload(persist_manager_with_payment: bool, at_midpoint: bool) {
3441         // Test that if we reload in the middle of an HTLC claim commitment signed dance we'll still
3442         // receive the PaymentSent event even if the ChannelManager had no idea about the payment when
3443         // it was last persisted.
3444         let chanmon_cfgs = create_chanmon_cfgs(2);
3445         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
3446         let (persister_a, persister_b, persister_c);
3447         let (chain_monitor_a, chain_monitor_b, chain_monitor_c);
3448         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
3449         let (nodes_0_deserialized, nodes_0_deserialized_b, nodes_0_deserialized_c);
3450         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
3451
3452         let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1).2;
3453
3454         let mut nodes_0_serialized = Vec::new();
3455         if !persist_manager_with_payment {
3456                 nodes_0_serialized = nodes[0].node.encode();
3457         }
3458
3459         let (our_payment_preimage, our_payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
3460
3461         if persist_manager_with_payment {
3462                 nodes_0_serialized = nodes[0].node.encode();
3463         }
3464
3465         nodes[1].node.claim_funds(our_payment_preimage);
3466         check_added_monitors!(nodes[1], 1);
3467         expect_payment_claimed!(nodes[1], our_payment_hash, 1_000_000);
3468
3469         if at_midpoint {
3470                 let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3471                 nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
3472                 nodes[0].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &updates.commitment_signed);
3473                 check_added_monitors!(nodes[0], 1);
3474         } else {
3475                 let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3476                 nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
3477                 commitment_signed_dance!(nodes[0], nodes[1], htlc_fulfill_updates.commitment_signed, false);
3478                 // Ignore the PaymentSent event which is now pending on nodes[0] - if we were to handle it we'd
3479                 // be expected to ignore the eventual conflicting PaymentFailed, but by not looking at it we
3480                 // expect to get the PaymentSent again later.
3481                 check_added_monitors(&nodes[0], 0);
3482         }
3483
3484         // The ChannelMonitor should always be the latest version, as we're required to persist it
3485         // during the commitment signed handling.
3486         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
3487         reload_node!(nodes[0], test_default_channel_config(), &nodes_0_serialized, &[&chan_0_monitor_serialized], persister_a, chain_monitor_a, nodes_0_deserialized);
3488
3489         let events = nodes[0].node.get_and_clear_pending_events();
3490         assert_eq!(events.len(), 2);
3491         if let Event::ChannelClosed { reason: ClosureReason::OutdatedChannelManager, .. } = events[0] {} else { panic!(); }
3492         if let Event::PaymentSent { payment_preimage, .. } = events[1] { assert_eq!(payment_preimage, our_payment_preimage); } else { panic!(); }
3493         // Note that we don't get a PaymentPathSuccessful here as we leave the HTLC pending to avoid
3494         // the double-claim that would otherwise appear at the end of this test.
3495         nodes[0].node.timer_tick_occurred();
3496         let as_broadcasted_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
3497         assert_eq!(as_broadcasted_txn.len(), 1);
3498
3499         // Ensure that, even after some time, if we restart we still include *something* in the current
3500         // `ChannelManager` which prevents a `PaymentFailed` when we restart even if pending resolved
3501         // payments have since been timed out thanks to `IDEMPOTENCY_TIMEOUT_TICKS`.
3502         // A naive implementation of the fix here would wipe the pending payments set, causing a
3503         // failure event when we restart.
3504         for _ in 0..(IDEMPOTENCY_TIMEOUT_TICKS * 2) { nodes[0].node.timer_tick_occurred(); }
3505
3506         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
3507         reload_node!(nodes[0], test_default_channel_config(), &nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister_b, chain_monitor_b, nodes_0_deserialized_b);
3508         let events = nodes[0].node.get_and_clear_pending_events();
3509         assert!(events.is_empty());
3510
3511         // Ensure that we don't generate any further events even after the channel-closing commitment
3512         // transaction is confirmed on-chain.
3513         confirm_transaction(&nodes[0], &as_broadcasted_txn[0]);
3514         for _ in 0..(IDEMPOTENCY_TIMEOUT_TICKS * 2) { nodes[0].node.timer_tick_occurred(); }
3515
3516         let events = nodes[0].node.get_and_clear_pending_events();
3517         assert!(events.is_empty());
3518
3519         let chan_0_monitor_serialized = get_monitor!(nodes[0], chan_id).encode();
3520         reload_node!(nodes[0], test_default_channel_config(), &nodes[0].node.encode(), &[&chan_0_monitor_serialized], persister_c, chain_monitor_c, nodes_0_deserialized_c);
3521         let events = nodes[0].node.get_and_clear_pending_events();
3522         assert!(events.is_empty());
3523         check_added_monitors(&nodes[0], 1);
3524 }
3525
3526 #[test]
3527 fn no_missing_sent_on_midpoint_reload() {
3528         do_no_missing_sent_on_reload(false, true);
3529         do_no_missing_sent_on_reload(true, true);
3530 }
3531
3532 #[test]
3533 fn no_missing_sent_on_reload() {
3534         do_no_missing_sent_on_reload(false, false);
3535         do_no_missing_sent_on_reload(true, false);
3536 }
3537
3538 fn do_claim_from_closed_chan(fail_payment: bool) {
3539         // Previously, LDK would refuse to claim a payment if a channel on which the payment was
3540         // received had been closed between when the HTLC was received and when we went to claim it.
3541         // This makes sense in the payment case - why pay an on-chain fee to claim the HTLC when
3542         // presumably the sender may retry later. Long ago it also reduced total code in the claim
3543         // pipeline.
3544         //
3545         // However, this doesn't make sense if you're trying to do an atomic swap or some other
3546         // protocol that requires atomicity with some other action - if your money got claimed
3547         // elsewhere you need to be able to claim the HTLC in lightning no matter what. Further, this
3548         // is an over-optimization - there should be a very, very low likelihood that a channel closes
3549         // between when we receive the last HTLC for a payment and the user goes to claim the payment.
3550         // Since we now have code to handle this anyway we should allow it.
3551
3552         // Build 4 nodes and send an MPP payment across two paths. By building a route manually set the
3553         // CLTVs on the paths to different value resulting in a different claim deadline.
3554         let chanmon_cfgs = create_chanmon_cfgs(4);
3555         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
3556         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
3557         let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);
3558
3559         create_announced_chan_between_nodes(&nodes, 0, 1);
3560         create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
3561         let chan_bd = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 1_000_000, 0).2;
3562         create_announced_chan_between_nodes(&nodes, 2, 3);
3563
3564         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash!(nodes[3]);
3565         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
3566                 .with_bolt11_features(nodes[1].node.bolt11_invoice_features()).unwrap();
3567         let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, 10_000_000);
3568         let mut route = nodes[0].router.find_route(&nodes[0].node.get_our_node_id(), &route_params,
3569                 None, nodes[0].node.compute_inflight_htlcs()).unwrap();
3570         // Make sure the route is ordered as the B->D path before C->D
3571         route.paths.sort_by(|a, _| if a.hops[0].pubkey == nodes[1].node.get_our_node_id() {
3572                 std::cmp::Ordering::Less } else { std::cmp::Ordering::Greater });
3573
3574         // Note that we add an extra 1 in the send pipeline to compensate for any blocks found while
3575         // the HTLC is being relayed.
3576         route.paths[0].hops[1].cltv_expiry_delta = TEST_FINAL_CLTV + 8;
3577         route.paths[1].hops[1].cltv_expiry_delta = TEST_FINAL_CLTV + 12;
3578         let final_cltv = nodes[0].best_block_info().1 + TEST_FINAL_CLTV + 8 + 1;
3579
3580         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
3581         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret),
3582                 PaymentId(payment_hash.0), route_params.clone(), Retry::Attempts(1)).unwrap();
3583         check_added_monitors(&nodes[0], 2);
3584         let mut send_msgs = nodes[0].node.get_and_clear_pending_msg_events();
3585         send_msgs.sort_by(|a, _| {
3586                 let a_node_id =
3587                         if let MessageSendEvent::UpdateHTLCs { node_id, .. } = a { node_id } else { panic!() };
3588                 let node_b_id = nodes[1].node.get_our_node_id();
3589                 if *a_node_id == node_b_id { std::cmp::Ordering::Less } else { std::cmp::Ordering::Greater }
3590         });
3591
3592         assert_eq!(send_msgs.len(), 2);
3593         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 10_000_000,
3594                 payment_hash, Some(payment_secret), send_msgs.remove(0), false, None);
3595         let receive_event = pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 10_000_000,
3596                 payment_hash, Some(payment_secret), send_msgs.remove(0), true, None);
3597
3598         match receive_event.unwrap() {
3599                 Event::PaymentClaimable { claim_deadline, .. } => {
3600                         assert_eq!(claim_deadline.unwrap(), final_cltv - HTLC_FAIL_BACK_BUFFER);
3601                 },
3602                 _ => panic!(),
3603         }
3604
3605         // Ensure that the claim_deadline is correct, with the payment failing at exactly the given
3606         // height.
3607         connect_blocks(&nodes[3], final_cltv - HTLC_FAIL_BACK_BUFFER - nodes[3].best_block_info().1
3608                 - if fail_payment { 0 } else { 2 });
3609         let error_message = "Channel force-closed";
3610         if fail_payment {
3611                 // We fail the HTLC on the A->B->D path first as it expires 4 blocks earlier. We go ahead
3612                 // and expire both immediately, though, by connecting another 4 blocks.
3613                 let reason = HTLCDestination::FailedPayment { payment_hash };
3614                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[3], [reason.clone()]);
3615                 connect_blocks(&nodes[3], 4);
3616                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[3], [reason]);
3617                 pass_failed_payment_back(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_hash, PaymentFailureReason::RecipientRejected);
3618         } else {
3619                 nodes[1].node.force_close_broadcasting_latest_txn(&chan_bd, &nodes[3].node.get_our_node_id(), error_message.to_string()).unwrap();
3620                 check_closed_event!(&nodes[1], 1, ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) }, false,
3621                         [nodes[3].node.get_our_node_id()], 1000000);
3622                 check_closed_broadcast(&nodes[1], 1, true);
3623                 let bs_tx = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
3624                 assert_eq!(bs_tx.len(), 1);
3625
3626                 mine_transaction(&nodes[3], &bs_tx[0]);
3627                 check_added_monitors(&nodes[3], 1);
3628                 check_closed_broadcast(&nodes[3], 1, true);
3629                 check_closed_event!(&nodes[3], 1, ClosureReason::CommitmentTxConfirmed, false,
3630                         [nodes[1].node.get_our_node_id()], 1000000);
3631
3632                 nodes[3].node.claim_funds(payment_preimage);
3633                 check_added_monitors(&nodes[3], 2);
3634                 expect_payment_claimed!(nodes[3], payment_hash, 10_000_000);
3635
3636                 let ds_tx = nodes[3].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
3637                 assert_eq!(ds_tx.len(), 1);
3638                 check_spends!(&ds_tx[0], &bs_tx[0]);
3639
3640                 mine_transactions(&nodes[1], &[&bs_tx[0], &ds_tx[0]]);
3641                 check_added_monitors(&nodes[1], 1);
3642                 expect_payment_forwarded!(nodes[1], nodes[0], nodes[3], Some(1000), false, true);
3643
3644                 let bs_claims = nodes[1].node.get_and_clear_pending_msg_events();
3645                 check_added_monitors(&nodes[1], 1);
3646                 assert_eq!(bs_claims.len(), 1);
3647                 if let MessageSendEvent::UpdateHTLCs { updates, .. } = &bs_claims[0] {
3648                         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
3649                         commitment_signed_dance!(nodes[0], nodes[1], updates.commitment_signed, false, true);
3650                 } else { panic!(); }
3651
3652                 expect_payment_sent!(nodes[0], payment_preimage);
3653
3654                 let ds_claim_msgs = nodes[3].node.get_and_clear_pending_msg_events();
3655                 assert_eq!(ds_claim_msgs.len(), 1);
3656                 let cs_claim_msgs = if let MessageSendEvent::UpdateHTLCs { updates, .. } = &ds_claim_msgs[0] {
3657                         nodes[2].node.handle_update_fulfill_htlc(&nodes[3].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
3658                         let cs_claim_msgs = nodes[2].node.get_and_clear_pending_msg_events();
3659                         check_added_monitors(&nodes[2], 1);
3660                         commitment_signed_dance!(nodes[2], nodes[3], updates.commitment_signed, false, true);
3661                         expect_payment_forwarded!(nodes[2], nodes[0], nodes[3], Some(1000), false, false);
3662                         cs_claim_msgs
3663                 } else { panic!(); };
3664
3665                 assert_eq!(cs_claim_msgs.len(), 1);
3666                 if let MessageSendEvent::UpdateHTLCs { updates, .. } = &cs_claim_msgs[0] {
3667                         nodes[0].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
3668                         commitment_signed_dance!(nodes[0], nodes[2], updates.commitment_signed, false, true);
3669                 } else { panic!(); }
3670
3671                 expect_payment_path_successful!(nodes[0]);
3672         }
3673 }
3674
3675 #[test]
3676 fn claim_from_closed_chan() {
3677         do_claim_from_closed_chan(true);
3678         do_claim_from_closed_chan(false);
3679 }
3680
3681 #[test]
3682 fn test_custom_tlvs_basic() {
3683         do_test_custom_tlvs(false, false, false);
3684         do_test_custom_tlvs(true, false, false);
3685 }
3686
3687 #[test]
3688 fn test_custom_tlvs_explicit_claim() {
3689         // Test that when receiving even custom TLVs the user must explicitly accept in case they
3690         // are unknown.
3691         do_test_custom_tlvs(false, true, false);
3692         do_test_custom_tlvs(false, true, true);
3693 }
3694
3695 fn do_test_custom_tlvs(spontaneous: bool, even_tlvs: bool, known_tlvs: bool) {
3696         let chanmon_cfgs = create_chanmon_cfgs(2);
3697         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
3698         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None; 2]);
3699         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
3700
3701         create_announced_chan_between_nodes(&nodes, 0, 1);
3702
3703         let amt_msat = 100_000;
3704         let (mut route, our_payment_hash, our_payment_preimage, our_payment_secret) = get_route_and_payment_hash!(&nodes[0], &nodes[1], amt_msat);
3705         let payment_id = PaymentId(our_payment_hash.0);
3706         let custom_tlvs = vec![
3707                 (if even_tlvs { 5482373482 } else { 5482373483 }, vec![1, 2, 3, 4]),
3708                 (5482373487, vec![0x42u8; 16]),
3709         ];
3710         let onion_fields = RecipientOnionFields {
3711                 payment_secret: if spontaneous { None } else { Some(our_payment_secret) },
3712                 payment_metadata: None,
3713                 custom_tlvs: custom_tlvs.clone()
3714         };
3715         if spontaneous {
3716                 nodes[0].node.send_spontaneous_payment(&route, Some(our_payment_preimage), onion_fields, payment_id).unwrap();
3717         } else {
3718                 nodes[0].node.send_payment_with_route(&route, our_payment_hash, onion_fields, payment_id).unwrap();
3719         }
3720         check_added_monitors(&nodes[0], 1);
3721
3722         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
3723         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
3724         let mut payment_event = SendEvent::from_event(ev);
3725
3726         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
3727         check_added_monitors!(&nodes[1], 0);
3728         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false);
3729         expect_pending_htlcs_forwardable!(nodes[1]);
3730
3731         let events = nodes[1].node.get_and_clear_pending_events();
3732         assert_eq!(events.len(), 1);
3733         match events[0] {
3734                 Event::PaymentClaimable { ref onion_fields, .. } => {
3735                         assert_eq!(onion_fields.clone().unwrap().custom_tlvs().clone(), custom_tlvs);
3736                 },
3737                 _ => panic!("Unexpected event"),
3738         }
3739
3740         match (known_tlvs, even_tlvs) {
3741                 (true, _) => {
3742                         nodes[1].node.claim_funds_with_known_custom_tlvs(our_payment_preimage);
3743                         let expected_total_fee_msat = pass_claimed_payment_along_route(
3744                                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1]]], our_payment_preimage)
3745                                         .with_custom_tlvs(custom_tlvs)
3746                         );
3747                         expect_payment_sent!(&nodes[0], our_payment_preimage, Some(expected_total_fee_msat));
3748                 },
3749                 (false, false) => {
3750                         claim_payment_along_route(
3751                                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1]]], our_payment_preimage)
3752                                         .with_custom_tlvs(custom_tlvs)
3753                         );
3754                 },
3755                 (false, true) => {
3756                         nodes[1].node.claim_funds(our_payment_preimage);
3757                         let expected_destinations = vec![HTLCDestination::FailedPayment { payment_hash: our_payment_hash }];
3758                         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[1], expected_destinations);
3759                         pass_failed_payment_back(&nodes[0], &[&[&nodes[1]]], false, our_payment_hash, PaymentFailureReason::RecipientRejected);
3760                 }
3761         }
3762 }
3763
3764 #[test]
3765 fn test_retry_custom_tlvs() {
3766         // Test that custom TLVs are successfully sent on retries
3767         let chanmon_cfgs = create_chanmon_cfgs(3);
3768         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
3769         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
3770         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
3771
3772         create_announced_chan_between_nodes(&nodes, 0, 1);
3773         let (chan_2_update, _, chan_2_id, _) = create_announced_chan_between_nodes(&nodes, 2, 1);
3774
3775         // Rebalance
3776         send_payment(&nodes[2], &vec!(&nodes[1])[..], 1_500_000);
3777
3778         let amt_msat = 1_000_000;
3779         let (mut route, payment_hash, payment_preimage, payment_secret) =
3780                 get_route_and_payment_hash!(nodes[0], nodes[2], amt_msat);
3781
3782         // Initiate the payment
3783         let payment_id = PaymentId(payment_hash.0);
3784         let mut route_params = route.route_params.clone().unwrap();
3785
3786         let custom_tlvs = vec![((1 << 16) + 1, vec![0x42u8; 16])];
3787         let onion_fields = RecipientOnionFields::secret_only(payment_secret);
3788         let onion_fields = onion_fields.with_custom_tlvs(custom_tlvs.clone()).unwrap();
3789
3790         nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
3791         nodes[0].node.send_payment(payment_hash, onion_fields,
3792                 payment_id, route_params.clone(), Retry::Attempts(1)).unwrap();
3793         check_added_monitors!(nodes[0], 1); // one monitor per path
3794
3795         // Add the HTLC along the first hop.
3796         let htlc_updates = get_htlc_update_msgs(&nodes[0], &nodes[1].node.get_our_node_id());
3797         let msgs::CommitmentUpdate { update_add_htlcs, commitment_signed, .. } = htlc_updates;
3798         assert_eq!(update_add_htlcs.len(), 1);
3799         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add_htlcs[0]);
3800         commitment_signed_dance!(nodes[1], nodes[0], commitment_signed, false);
3801
3802         // Attempt to forward the payment and complete the path's failure.
3803         expect_pending_htlcs_forwardable!(&nodes[1]);
3804         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[1],
3805                 vec![HTLCDestination::NextHopChannel {
3806                         node_id: Some(nodes[2].node.get_our_node_id()),
3807                         channel_id: chan_2_id
3808                 }]);
3809         check_added_monitors!(nodes[1], 1);
3810
3811         let htlc_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
3812         let msgs::CommitmentUpdate { update_fail_htlcs, commitment_signed, .. } = htlc_updates;
3813         assert_eq!(update_fail_htlcs.len(), 1);
3814         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &update_fail_htlcs[0]);
3815         commitment_signed_dance!(nodes[0], nodes[1], commitment_signed, false);
3816
3817         let mut events = nodes[0].node.get_and_clear_pending_events();
3818         match events[1] {
3819                 Event::PendingHTLCsForwardable { .. } => {},
3820                 _ => panic!("Unexpected event")
3821         }
3822         events.remove(1);
3823         expect_payment_failed_conditions_event(events, payment_hash, false,
3824                 PaymentFailedConditions::new().mpp_parts_remain());
3825
3826         // Rebalance the channel so the retry of the payment can succeed.
3827         send_payment(&nodes[2], &vec!(&nodes[1])[..], 1_500_000);
3828
3829         // Retry the payment and make sure it succeeds
3830         route_params.payment_params.previously_failed_channels.push(chan_2_update.contents.short_channel_id);
3831         route.route_params = Some(route_params.clone());
3832         nodes[0].router.expect_find_route(route_params, Ok(route));
3833         nodes[0].node.process_pending_htlc_forwards();
3834         check_added_monitors!(nodes[0], 1);
3835         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
3836         assert_eq!(events.len(), 1);
3837         let path = &[&nodes[1], &nodes[2]];
3838         let args = PassAlongPathArgs::new(&nodes[0], path, 1_000_000, payment_hash, events.pop().unwrap())
3839                 .with_payment_secret(payment_secret)
3840                 .with_custom_tlvs(custom_tlvs.clone());
3841         do_pass_along_path(args);
3842         claim_payment_along_route(
3843                 ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
3844                         .with_custom_tlvs(custom_tlvs)
3845         );
3846 }
3847
3848 #[test]
3849 fn test_custom_tlvs_consistency() {
3850         let even_type_1 = 1 << 16;
3851         let odd_type_1  = (1 << 16)+ 1;
3852         let even_type_2 = (1 << 16) + 2;
3853         let odd_type_2  = (1 << 16) + 3;
3854         let value_1 = || vec![1, 2, 3, 4];
3855         let differing_value_1 = || vec![1, 2, 3, 5];
3856         let value_2 = || vec![42u8; 16];
3857
3858         // Drop missing odd tlvs
3859         do_test_custom_tlvs_consistency(
3860                 vec![(odd_type_1, value_1()), (odd_type_2, value_2())],
3861                 vec![(odd_type_1, value_1())],
3862                 Some(vec![(odd_type_1, value_1())]),
3863         );
3864         // Drop non-matching odd tlvs
3865         do_test_custom_tlvs_consistency(
3866                 vec![(odd_type_1, value_1()), (odd_type_2, value_2())],
3867                 vec![(odd_type_1, differing_value_1()), (odd_type_2, value_2())],
3868                 Some(vec![(odd_type_2, value_2())]),
3869         );
3870         // Fail missing even tlvs
3871         do_test_custom_tlvs_consistency(
3872                 vec![(odd_type_1, value_1()), (even_type_2, value_2())],
3873                 vec![(odd_type_1, value_1())],
3874                 None,
3875         );
3876         // Fail non-matching even tlvs
3877         do_test_custom_tlvs_consistency(
3878                 vec![(even_type_1, value_1()), (odd_type_2, value_2())],
3879                 vec![(even_type_1, differing_value_1()), (odd_type_2, value_2())],
3880                 None,
3881         );
3882 }
3883
3884 fn do_test_custom_tlvs_consistency(first_tlvs: Vec<(u64, Vec<u8>)>, second_tlvs: Vec<(u64, Vec<u8>)>,
3885         expected_receive_tlvs: Option<Vec<(u64, Vec<u8>)>>) {
3886
3887         let chanmon_cfgs = create_chanmon_cfgs(4);
3888         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
3889         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
3890         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
3891
3892         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
3893         create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 100_000, 0);
3894         create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 100_000, 0);
3895         let chan_2_3 = create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 100_000, 0);
3896
3897         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
3898                 .with_bolt11_features(nodes[3].node.bolt11_invoice_features()).unwrap();
3899         let mut route = get_route!(nodes[0], payment_params, 15_000_000).unwrap();
3900         assert_eq!(route.paths.len(), 2);
3901         route.paths.sort_by(|path_a, _| {
3902                 // Sort the path so that the path through nodes[1] comes first
3903                 if path_a.hops[0].pubkey == nodes[1].node.get_our_node_id() {
3904                         core::cmp::Ordering::Less } else { core::cmp::Ordering::Greater }
3905         });
3906
3907         let (our_payment_preimage, our_payment_hash, our_payment_secret) = get_payment_preimage_hash!(&nodes[3]);
3908         let payment_id = PaymentId([42; 32]);
3909         let amt_msat = 15_000_000;
3910
3911         // Send first part
3912         let onion_fields = RecipientOnionFields {
3913                 payment_secret: Some(our_payment_secret),
3914                 payment_metadata: None,
3915                 custom_tlvs: first_tlvs
3916         };
3917         let session_privs = nodes[0].node.test_add_new_pending_payment(our_payment_hash,
3918                         onion_fields.clone(), payment_id, &route).unwrap();
3919         let cur_height = nodes[0].best_block_info().1;
3920         nodes[0].node.test_send_payment_along_path(&route.paths[0], &our_payment_hash,
3921                 onion_fields.clone(), amt_msat, cur_height, payment_id,
3922                 &None, session_privs[0]).unwrap();
3923         check_added_monitors!(nodes[0], 1);
3924
3925         {
3926                 let mut events = nodes[0].node.get_and_clear_pending_msg_events();
3927                 assert_eq!(events.len(), 1);
3928                 pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], amt_msat, our_payment_hash,
3929                         Some(our_payment_secret), events.pop().unwrap(), false, None);
3930         }
3931         assert!(nodes[3].node.get_and_clear_pending_events().is_empty());
3932
3933         // Send second part
3934         let onion_fields = RecipientOnionFields {
3935                 payment_secret: Some(our_payment_secret),
3936                 payment_metadata: None,
3937                 custom_tlvs: second_tlvs
3938         };
3939         nodes[0].node.test_send_payment_along_path(&route.paths[1], &our_payment_hash,
3940                 onion_fields.clone(), amt_msat, cur_height, payment_id, &None, session_privs[1]).unwrap();
3941         check_added_monitors!(nodes[0], 1);
3942
3943         {
3944                 let mut events = nodes[0].node.get_and_clear_pending_msg_events();
3945                 assert_eq!(events.len(), 1);
3946                 let payment_event = SendEvent::from_event(events.pop().unwrap());
3947
3948                 nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
3949                 commitment_signed_dance!(nodes[2], nodes[0], payment_event.commitment_msg, false);
3950
3951                 expect_pending_htlcs_forwardable!(nodes[2]);
3952                 check_added_monitors!(nodes[2], 1);
3953
3954                 let mut events = nodes[2].node.get_and_clear_pending_msg_events();
3955                 assert_eq!(events.len(), 1);
3956                 let payment_event = SendEvent::from_event(events.pop().unwrap());
3957
3958                 nodes[3].node.handle_update_add_htlc(&nodes[2].node.get_our_node_id(), &payment_event.msgs[0]);
3959                 check_added_monitors!(nodes[3], 0);
3960                 commitment_signed_dance!(nodes[3], nodes[2], payment_event.commitment_msg, true, true);
3961         }
3962         expect_pending_htlcs_forwardable_ignore!(nodes[3]);
3963         nodes[3].node.process_pending_htlc_forwards();
3964
3965         if let Some(expected_tlvs) = expected_receive_tlvs {
3966                 // Claim and match expected
3967                 let events = nodes[3].node.get_and_clear_pending_events();
3968                 assert_eq!(events.len(), 1);
3969                 match events[0] {
3970                         Event::PaymentClaimable { ref onion_fields, .. } => {
3971                                 assert_eq!(onion_fields.clone().unwrap().custom_tlvs, expected_tlvs);
3972                         },
3973                         _ => panic!("Unexpected event"),
3974                 }
3975
3976                 do_claim_payment_along_route(
3977                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], our_payment_preimage)
3978                                 .with_custom_tlvs(expected_tlvs)
3979                 );
3980                 expect_payment_sent(&nodes[0], our_payment_preimage, Some(Some(2000)), true, true);
3981         } else {
3982                 // Expect fail back
3983                 let expected_destinations = vec![HTLCDestination::FailedPayment { payment_hash: our_payment_hash }];
3984                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[3], expected_destinations);
3985                 check_added_monitors!(nodes[3], 1);
3986
3987                 let fail_updates_1 = get_htlc_update_msgs!(nodes[3], nodes[2].node.get_our_node_id());
3988                 nodes[2].node.handle_update_fail_htlc(&nodes[3].node.get_our_node_id(), &fail_updates_1.update_fail_htlcs[0]);
3989                 commitment_signed_dance!(nodes[2], nodes[3], fail_updates_1.commitment_signed, false);
3990
3991                 expect_pending_htlcs_forwardable_and_htlc_handling_failed!(nodes[2], vec![
3992                         HTLCDestination::NextHopChannel {
3993                                 node_id: Some(nodes[3].node.get_our_node_id()),
3994                                 channel_id: chan_2_3.2
3995                         }]);
3996                 check_added_monitors!(nodes[2], 1);
3997
3998                 let fail_updates_2 = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id());
3999                 nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &fail_updates_2.update_fail_htlcs[0]);
4000                 commitment_signed_dance!(nodes[0], nodes[2], fail_updates_2.commitment_signed, false);
4001
4002                 expect_payment_failed_conditions(&nodes[0], our_payment_hash, true,
4003                         PaymentFailedConditions::new().mpp_parts_remain());
4004         }
4005 }
4006
4007 fn do_test_payment_metadata_consistency(do_reload: bool, do_modify: bool) {
4008         // Check that a payment metadata received on one HTLC that doesn't match the one received on
4009         // another results in the HTLC being rejected.
4010         //
4011         // We first set up a diamond shaped network, allowing us to split a payment into two HTLCs, the
4012         // first of which we'll deliver and the second of which we'll fail and then re-send with
4013         // modified payment metadata, which will in turn result in it being failed by the recipient.
4014         let chanmon_cfgs = create_chanmon_cfgs(4);
4015         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
4016         let persister;
4017         let new_chain_monitor;
4018
4019         let mut config = test_default_channel_config();
4020         config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 50;
4021         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, Some(config), Some(config), Some(config)]);
4022         let nodes_0_deserialized;
4023
4024         let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);
4025
4026         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
4027         let chan_id_bd = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 1_000_000, 0).2;
4028         create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
4029         let chan_id_cd = create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 1_000_000, 0).2;
4030
4031         // Pay more than half of each channel's max, requiring MPP
4032         let amt_msat = 750_000_000;
4033         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash!(nodes[3], Some(amt_msat));
4034         let payment_id = PaymentId(payment_hash.0);
4035         let payment_metadata = vec![44, 49, 52, 142];
4036
4037         let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
4038                 .with_bolt11_features(nodes[1].node.bolt11_invoice_features()).unwrap();
4039         let mut route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
4040
4041         // Send the MPP payment, delivering the updated commitment state to nodes[1].
4042         nodes[0].node.send_payment(payment_hash, RecipientOnionFields {
4043                         payment_secret: Some(payment_secret), payment_metadata: Some(payment_metadata), custom_tlvs: vec![],
4044                 }, payment_id, route_params.clone(), Retry::Attempts(1)).unwrap();
4045         check_added_monitors!(nodes[0], 2);
4046
4047         let mut send_events = nodes[0].node.get_and_clear_pending_msg_events();
4048         assert_eq!(send_events.len(), 2);
4049         let first_send = SendEvent::from_event(send_events.pop().unwrap());
4050         let second_send = SendEvent::from_event(send_events.pop().unwrap());
4051
4052         let (b_recv_ev, c_recv_ev) = if first_send.node_id == nodes[1].node.get_our_node_id() {
4053                 (&first_send, &second_send)
4054         } else {
4055                 (&second_send, &first_send)
4056         };
4057         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &b_recv_ev.msgs[0]);
4058         commitment_signed_dance!(nodes[1], nodes[0], b_recv_ev.commitment_msg, false, true);
4059
4060         expect_pending_htlcs_forwardable!(nodes[1]);
4061         check_added_monitors(&nodes[1], 1);
4062         let b_forward_ev = SendEvent::from_node(&nodes[1]);
4063         nodes[3].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &b_forward_ev.msgs[0]);
4064         commitment_signed_dance!(nodes[3], nodes[1], b_forward_ev.commitment_msg, false, true);
4065
4066         expect_pending_htlcs_forwardable!(nodes[3]);
4067
4068         // Before delivering the second MPP HTLC to nodes[2], disconnect nodes[2] and nodes[3], which
4069         // will result in nodes[2] failing the HTLC back.
4070         nodes[2].node.peer_disconnected(&nodes[3].node.get_our_node_id());
4071         nodes[3].node.peer_disconnected(&nodes[2].node.get_our_node_id());
4072
4073         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &c_recv_ev.msgs[0]);
4074         commitment_signed_dance!(nodes[2], nodes[0], c_recv_ev.commitment_msg, false, true);
4075
4076         let cs_fail = get_htlc_update_msgs(&nodes[2], &nodes[0].node.get_our_node_id());
4077         nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &cs_fail.update_fail_htlcs[0]);
4078         commitment_signed_dance!(nodes[0], nodes[2], cs_fail.commitment_signed, false, true);
4079
4080         let payment_fail_retryable_evs = nodes[0].node.get_and_clear_pending_events();
4081         assert_eq!(payment_fail_retryable_evs.len(), 2);
4082         if let Event::PaymentPathFailed { .. } = payment_fail_retryable_evs[0] {} else { panic!(); }
4083         if let Event::PendingHTLCsForwardable { .. } = payment_fail_retryable_evs[1] {} else { panic!(); }
4084
4085         // Before we allow the HTLC to be retried, optionally change the payment_metadata we have
4086         // stored for our payment.
4087         if do_modify {
4088                 nodes[0].node.test_set_payment_metadata(payment_id, Some(Vec::new()));
4089         }
4090
4091         // Optionally reload nodes[3] to check that the payment_metadata is properly serialized with
4092         // the payment state.
4093         if do_reload {
4094                 let mon_bd = get_monitor!(nodes[3], chan_id_bd).encode();
4095                 let mon_cd = get_monitor!(nodes[3], chan_id_cd).encode();
4096                 reload_node!(nodes[3], config, &nodes[3].node.encode(), &[&mon_bd, &mon_cd],
4097                         persister, new_chain_monitor, nodes_0_deserialized);
4098                 nodes[1].node.peer_disconnected(&nodes[3].node.get_our_node_id());
4099                 reconnect_nodes(ReconnectArgs::new(&nodes[1], &nodes[3]));
4100         }
4101         let mut reconnect_args = ReconnectArgs::new(&nodes[2], &nodes[3]);
4102         reconnect_args.send_channel_ready = (true, true);
4103         reconnect_nodes(reconnect_args);
4104
4105         // Create a new channel between C and D as A will refuse to retry on the existing one because
4106         // it just failed.
4107         create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 1_000_000, 0);
4108
4109         // Now retry the failed HTLC.
4110         nodes[0].node.process_pending_htlc_forwards();
4111         check_added_monitors(&nodes[0], 1);
4112         let as_resend = SendEvent::from_node(&nodes[0]);
4113         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &as_resend.msgs[0]);
4114         commitment_signed_dance!(nodes[2], nodes[0], as_resend.commitment_msg, false, true);
4115
4116         expect_pending_htlcs_forwardable!(nodes[2]);
4117         check_added_monitors(&nodes[2], 1);
4118         let cs_forward = SendEvent::from_node(&nodes[2]);
4119         let cd_channel_used = cs_forward.msgs[0].channel_id;
4120         nodes[3].node.handle_update_add_htlc(&nodes[2].node.get_our_node_id(), &cs_forward.msgs[0]);
4121         commitment_signed_dance!(nodes[3], nodes[2], cs_forward.commitment_msg, false, true);
4122
4123         // Finally, check that nodes[3] does the correct thing - either accepting the payment or, if
4124         // the payment metadata was modified, failing only the one modified HTLC and retaining the
4125         // other.
4126         if do_modify {
4127                 expect_pending_htlcs_forwardable_ignore!(nodes[3]);
4128                 nodes[3].node.process_pending_htlc_forwards();
4129                 expect_pending_htlcs_forwardable_conditions(nodes[3].node.get_and_clear_pending_events(),
4130                         &[HTLCDestination::FailedPayment {payment_hash}]);
4131                 nodes[3].node.process_pending_htlc_forwards();
4132
4133                 check_added_monitors(&nodes[3], 1);
4134                 let ds_fail = get_htlc_update_msgs(&nodes[3], &nodes[2].node.get_our_node_id());
4135
4136                 nodes[2].node.handle_update_fail_htlc(&nodes[3].node.get_our_node_id(), &ds_fail.update_fail_htlcs[0]);
4137                 commitment_signed_dance!(nodes[2], nodes[3], ds_fail.commitment_signed, false, true);
4138                 expect_pending_htlcs_forwardable_conditions(nodes[2].node.get_and_clear_pending_events(),
4139                         &[HTLCDestination::NextHopChannel { node_id: Some(nodes[3].node.get_our_node_id()), channel_id: cd_channel_used }]);
4140         } else {
4141                 expect_pending_htlcs_forwardable!(nodes[3]);
4142                 expect_payment_claimable!(nodes[3], payment_hash, payment_secret, amt_msat);
4143                 claim_payment_along_route(
4144                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], payment_preimage)
4145                 );
4146         }
4147 }
4148
4149 #[test]
4150 fn test_payment_metadata_consistency() {
4151         do_test_payment_metadata_consistency(true, true);
4152         do_test_payment_metadata_consistency(true, false);
4153         do_test_payment_metadata_consistency(false, true);
4154         do_test_payment_metadata_consistency(false, false);
4155 }
4156
4157 #[test]
4158 fn  test_htlc_forward_considers_anchor_outputs_value() {
4159         // Tests that:
4160         //
4161         // 1) Forwarding nodes don't forward HTLCs that would cause their balance to dip below the
4162         //    reserve when considering the value of anchor outputs.
4163         //
4164         // 2) Recipients of `update_add_htlc` properly reject HTLCs that would cause the initiator's
4165         //    balance to dip below the reserve when considering the value of anchor outputs.
4166         let mut config = test_default_channel_config();
4167         config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx = true;
4168         config.manually_accept_inbound_channels = true;
4169         config.channel_config.forwarding_fee_base_msat = 0;
4170         config.channel_config.forwarding_fee_proportional_millionths = 0;
4171
4172         // Set up a test network of three nodes that replicates a production failure leading to the
4173         // discovery of this bug.
4174         let chanmon_cfgs = create_chanmon_cfgs(3);
4175         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4176         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[Some(config), Some(config), Some(config)]);
4177         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4178
4179         const CHAN_AMT: u64 = 1_000_000;
4180         const PUSH_MSAT: u64 = 900_000_000;
4181         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, CHAN_AMT, 500_000_000);
4182         let (_, _, chan_id_2, _) = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, CHAN_AMT, PUSH_MSAT);
4183
4184         let channel_reserve_msat = get_holder_selected_channel_reserve_satoshis(CHAN_AMT, &config) * 1000;
4185         let commitment_fee_msat = commit_tx_fee_msat(
4186                 *nodes[1].fee_estimator.sat_per_kw.lock().unwrap(), 2, &ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()
4187         );
4188         let anchor_outpus_value_msat = ANCHOR_OUTPUT_VALUE_SATOSHI * 2 * 1000;
4189         let sendable_balance_msat = CHAN_AMT * 1000 - PUSH_MSAT - channel_reserve_msat - commitment_fee_msat - anchor_outpus_value_msat;
4190         let channel_details = nodes[1].node.list_channels().into_iter().find(|channel| channel.channel_id == chan_id_2).unwrap();
4191         assert!(sendable_balance_msat >= channel_details.next_outbound_htlc_minimum_msat);
4192         assert!(sendable_balance_msat <= channel_details.next_outbound_htlc_limit_msat);
4193
4194         send_payment(&nodes[0], &[&nodes[1], &nodes[2]], sendable_balance_msat);
4195         send_payment(&nodes[2], &[&nodes[1], &nodes[0]], sendable_balance_msat);
4196
4197         // Send out an HTLC that would cause the forwarding node to dip below its reserve when
4198         // considering the value of anchor outputs.
4199         let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(
4200                 nodes[0], nodes[2], sendable_balance_msat + anchor_outpus_value_msat
4201         );
4202         nodes[0].node.send_payment_with_route(
4203                 &route, payment_hash, RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
4204         ).unwrap();
4205         check_added_monitors!(nodes[0], 1);
4206
4207         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
4208         assert_eq!(events.len(), 1);
4209         let mut update_add_htlc = if let MessageSendEvent::UpdateHTLCs { updates, .. } = events.pop().unwrap() {
4210                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &updates.update_add_htlcs[0]);
4211                 check_added_monitors(&nodes[1], 0);
4212                 commitment_signed_dance!(nodes[1], nodes[0], &updates.commitment_signed, false);
4213                 updates.update_add_htlcs[0].clone()
4214         } else {
4215                 panic!("Unexpected event");
4216         };
4217
4218         // The forwarding node should reject forwarding it as expected.
4219         expect_pending_htlcs_forwardable!(nodes[1]);
4220         expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[1], vec![HTLCDestination::NextHopChannel {
4221                 node_id: Some(nodes[2].node.get_our_node_id()),
4222                 channel_id: chan_id_2
4223         }]);
4224         check_added_monitors(&nodes[1], 1);
4225
4226         let mut events = nodes[1].node.get_and_clear_pending_msg_events();
4227         assert_eq!(events.len(), 1);
4228         if let MessageSendEvent::UpdateHTLCs { updates, .. } = events.pop().unwrap() {
4229                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
4230                 check_added_monitors(&nodes[0], 0);
4231                 commitment_signed_dance!(nodes[0], nodes[1], &updates.commitment_signed, false);
4232         } else {
4233                 panic!("Unexpected event");
4234         }
4235
4236         expect_payment_failed!(nodes[0], payment_hash, false);
4237
4238         // Assume that the forwarding node did forward it, and make sure the recipient rejects it as an
4239         // invalid update and closes the channel.
4240         update_add_htlc.channel_id = chan_id_2;
4241         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &update_add_htlc);
4242         check_closed_event(&nodes[2], 1, ClosureReason::ProcessingError {
4243                 err: "Remote HTLC add would put them under remote reserve value".to_owned()
4244         }, false, &[nodes[1].node.get_our_node_id()], 1_000_000);
4245         check_closed_broadcast(&nodes[2], 1, true);
4246         check_added_monitors(&nodes[2], 1);
4247 }
4248
4249 #[test]
4250 fn peel_payment_onion_custom_tlvs() {
4251         let chanmon_cfgs = create_chanmon_cfgs(2);
4252         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
4253         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
4254         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
4255         create_announced_chan_between_nodes(&nodes, 0, 1);
4256         let secp_ctx = Secp256k1::new();
4257
4258         let amt_msat = 1000;
4259         let payment_params = PaymentParameters::for_keysend(nodes[1].node.get_our_node_id(),
4260                 TEST_FINAL_CLTV, false);
4261         let route_params = RouteParameters::from_payment_params_and_value(payment_params, amt_msat);
4262         let route = functional_test_utils::get_route(&nodes[0], &route_params).unwrap();
4263         let mut recipient_onion = RecipientOnionFields::spontaneous_empty()
4264                 .with_custom_tlvs(vec![(414141, vec![42; 1200])]).unwrap();
4265         let prng_seed = chanmon_cfgs[0].keys_manager.get_secure_random_bytes();
4266         let session_priv = SecretKey::from_slice(&prng_seed[..]).expect("RNG is busted");
4267         let keysend_preimage = PaymentPreimage([42; 32]);
4268         let payment_hash = PaymentHash(Sha256::hash(&keysend_preimage.0).to_byte_array());
4269
4270         let (onion_routing_packet, first_hop_msat, cltv_expiry) = onion_utils::create_payment_onion(
4271                 &secp_ctx, &route.paths[0], &session_priv, amt_msat, &recipient_onion,
4272                 nodes[0].best_block_info().1, &payment_hash, &Some(keysend_preimage), prng_seed
4273         ).unwrap();
4274
4275         let update_add = msgs::UpdateAddHTLC {
4276                 channel_id: ChannelId([0; 32]),
4277                 htlc_id: 42,
4278                 amount_msat: first_hop_msat,
4279                 payment_hash,
4280                 cltv_expiry,
4281                 skimmed_fee_msat: None,
4282                 onion_routing_packet,
4283                 blinding_point: None,
4284         };
4285         let peeled_onion = crate::ln::onion_payment::peel_payment_onion(
4286                 &update_add, &&chanmon_cfgs[1].keys_manager, &&chanmon_cfgs[1].logger, &secp_ctx,
4287                 nodes[1].best_block_info().1, true, false
4288         ).unwrap();
4289         assert_eq!(peeled_onion.incoming_amt_msat, Some(amt_msat));
4290         match peeled_onion.routing {
4291                 PendingHTLCRouting::ReceiveKeysend {
4292                         payment_data, payment_metadata, custom_tlvs, ..
4293                 } => {
4294                         #[cfg(not(c_bindings))]
4295                         assert_eq!(&custom_tlvs, recipient_onion.custom_tlvs());
4296                         #[cfg(c_bindings)]
4297                         assert_eq!(custom_tlvs, recipient_onion.custom_tlvs());
4298                         assert!(payment_metadata.is_none());
4299                         assert!(payment_data.is_none());
4300                 },
4301                 _ => panic!()
4302         }
4303 }
4304
4305 #[test]
4306 fn test_non_strict_forwarding() {
4307         let chanmon_cfgs = create_chanmon_cfgs(3);
4308         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4309         let mut config = test_default_channel_config();
4310         config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100;
4311         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[Some(config), Some(config), Some(config)]);
4312         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4313
4314         // Create a routing node with two outbound channels, each of which can forward 2 payments of
4315         // the given value.
4316         let payment_value = 1_500_000;
4317         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 100_000, 0);
4318         let (chan_update_1, _, channel_id_1, _) = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 4_950, 0);
4319         let (chan_update_2, _, channel_id_2, _) = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 5_000, 0);
4320
4321         // Create a route once.
4322         let payment_params = PaymentParameters::from_node_id(nodes[2].node.get_our_node_id(), TEST_FINAL_CLTV)
4323                 .with_bolt11_features(nodes[2].node.bolt11_invoice_features()).unwrap();
4324         let route_params = RouteParameters::from_payment_params_and_value(payment_params, payment_value);
4325         let route = functional_test_utils::get_route(&nodes[0], &route_params).unwrap();
4326
4327         // Send 4 payments over the same route.
4328         for i in 0..4 {
4329                 let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(payment_value), None);
4330                 nodes[0].node.send_payment_with_route(&route, payment_hash,
4331                         RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
4332                 check_added_monitors!(nodes[0], 1);
4333                 let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
4334                 assert_eq!(msg_events.len(), 1);
4335                 let mut send_event = SendEvent::from_event(msg_events.remove(0));
4336                 nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
4337                 commitment_signed_dance!(nodes[1], nodes[0], &send_event.commitment_msg, false);
4338
4339                 expect_pending_htlcs_forwardable!(nodes[1]);
4340                 check_added_monitors!(nodes[1], 1);
4341                 msg_events = nodes[1].node.get_and_clear_pending_msg_events();
4342                 assert_eq!(msg_events.len(), 1);
4343                 send_event = SendEvent::from_event(msg_events.remove(0));
4344                 // The HTLC will be forwarded over the most appropriate channel with the corresponding peer,
4345                 // applying non-strict forwarding.
4346                 // The channel with the least amount of outbound liquidity will be used to maximize the
4347                 // probability of being able to successfully forward a subsequent HTLC.
4348                 assert_eq!(send_event.msgs[0].channel_id, if i < 2 {
4349                         channel_id_1
4350                 } else {
4351                         channel_id_2
4352                 });
4353                 nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &send_event.msgs[0]);
4354                 commitment_signed_dance!(nodes[2], nodes[1], &send_event.commitment_msg, false);
4355
4356                 expect_pending_htlcs_forwardable!(nodes[2]);
4357                 let events = nodes[2].node.get_and_clear_pending_events();
4358                 assert_eq!(events.len(), 1);
4359                 assert!(matches!(events[0], Event::PaymentClaimable { .. }));
4360
4361                 claim_payment_along_route(
4362                         ClaimAlongRouteArgs::new(&nodes[0], &[&[&nodes[1], &nodes[2]]], payment_preimage)
4363                 );
4364         }
4365
4366         // Send a 5th payment which will fail.
4367         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(payment_value), None);
4368         nodes[0].node.send_payment_with_route(&route, payment_hash,
4369                 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)).unwrap();
4370         check_added_monitors!(nodes[0], 1);
4371         let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
4372         assert_eq!(msg_events.len(), 1);
4373         let mut send_event = SendEvent::from_event(msg_events.remove(0));
4374         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &send_event.msgs[0]);
4375         commitment_signed_dance!(nodes[1], nodes[0], &send_event.commitment_msg, false);
4376
4377         expect_pending_htlcs_forwardable!(nodes[1]);
4378         check_added_monitors!(nodes[1], 1);
4379         let routed_scid = route.paths[0].hops[1].short_channel_id;
4380         let routed_channel_id = match routed_scid {
4381                 scid if scid == chan_update_1.contents.short_channel_id => channel_id_1,
4382                 scid if scid == chan_update_2.contents.short_channel_id => channel_id_2,
4383                 _ => panic!("Unexpected short channel id in route"),
4384         };
4385         // The failure to forward will refer to the channel given in the onion.
4386         expect_pending_htlcs_forwardable_conditions(nodes[1].node.get_and_clear_pending_events(),
4387                 &[HTLCDestination::NextHopChannel { node_id: Some(nodes[2].node.get_our_node_id()), channel_id: routed_channel_id }]);
4388
4389         let updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
4390         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
4391         commitment_signed_dance!(nodes[0], nodes[1], updates.commitment_signed, false);
4392         let events = nodes[0].node.get_and_clear_pending_events();
4393         expect_payment_failed_conditions_event(events, payment_hash, false, PaymentFailedConditions::new().blamed_scid(routed_scid));
4394 }