_ 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 chain::{ChannelMonitorUpdateErr, Confirm, Listen, Watch};
  15 use chain::channelmonitor::{ANTI_REORG_DELAY, ChannelMonitor, LATENCY_GRACE_PERIOD_BLOCKS};
  16 use chain::transaction::OutPoint;
  17 use chain::keysinterface::KeysInterface;
  18 use ln::channelmanager::{BREAKDOWN_TIMEOUT, ChannelManager, ChannelManagerReadArgs, MPP_TIMEOUT_TICKS, PaymentId, PaymentSendFailure};
  19 use ln::features::{InitFeatures, InvoiceFeatures};
  20 use ln::msgs;
  21 use ln::msgs::ChannelMessageHandler;
  22 use routing::router::{PaymentParameters, get_route};
  23 use util::events::{ClosureReason, Event, MessageSendEvent, MessageSendEventsProvider};
  24 use util::test_utils;
  25 use util::errors::APIError;
  26 use util::enforcing_trait_impls::EnforcingSigner;
  27 use util::ser::{ReadableArgs, Writeable};
  28 use io;
  29
  30 use bitcoin::{Block, BlockHeader, BlockHash};
  31 use bitcoin::network::constants::Network;
  32
  33 use prelude::*;
  34
  35 use ln::functional_test_utils::*;
  36
  37 #[test]
  38 fn retry_single_path_payment() {
  39         let chanmon_cfgs = create_chanmon_cfgs(3);
  40         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
  41         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
  42         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
  43
  44         let _chan_0 = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
  45         let _chan_1 = create_announced_chan_between_nodes(&nodes, 2, 1, InitFeatures::known(), InitFeatures::known());
  46         // Rebalance to find a route
  47         send_payment(&nodes[2], &vec!(&nodes[1])[..], 3_000_000);
  48
  49         let (route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], 100_000);
  50
  51         // Rebalance so that the first hop fails.
  52         send_payment(&nodes[1], &vec!(&nodes[2])[..], 2_000_000);
  53
  54         // Make sure the payment fails on the first hop.
  55         let payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
  56         check_added_monitors!(nodes[0], 1);
  57         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
  58         assert_eq!(events.len(), 1);
  59         let mut payment_event = SendEvent::from_event(events.pop().unwrap());
  60         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
  61         check_added_monitors!(nodes[1], 0);
  62         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false);
  63         expect_pending_htlcs_forwardable!(nodes[1]);
  64         expect_pending_htlcs_forwardable!(&nodes[1]);
  65         let htlc_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
  66         assert!(htlc_updates.update_add_htlcs.is_empty());
  67         assert_eq!(htlc_updates.update_fail_htlcs.len(), 1);
  68         assert!(htlc_updates.update_fulfill_htlcs.is_empty());
  69         assert!(htlc_updates.update_fail_malformed_htlcs.is_empty());
  70         check_added_monitors!(nodes[1], 1);
  71         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_updates.update_fail_htlcs[0]);
  72         commitment_signed_dance!(nodes[0], nodes[1], htlc_updates.commitment_signed, false);
  73         expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain());
  74
  75         // Rebalance the channel so the retry succeeds.
  76         send_payment(&nodes[2], &vec!(&nodes[1])[..], 3_000_000);
  77
  78         // Mine two blocks (we expire retries after 3, so this will check that we don't expire early)
  79         connect_blocks(&nodes[0], 2);
  80
  81         // Retry the payment and make sure it succeeds.
  82         nodes[0].node.retry_payment(&route, payment_id).unwrap();
  83         check_added_monitors!(nodes[0], 1);
  84         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
  85         assert_eq!(events.len(), 1);
  86         pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], 100_000, payment_hash, Some(payment_secret), events.pop().unwrap(), true, None);
  87         claim_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[2]]], false, payment_preimage);
  88 }
  89
  90 #[test]
  91 fn mpp_failure() {
  92         let chanmon_cfgs = create_chanmon_cfgs(4);
  93         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
  94         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
  95         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
  96
  97         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
  98         let chan_2_id = create_announced_chan_between_nodes(&nodes, 0, 2, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
  99         let chan_3_id = create_announced_chan_between_nodes(&nodes, 1, 3, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 100         let chan_4_id = create_announced_chan_between_nodes(&nodes, 2, 3, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 101
 102         let (mut route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(&nodes[0], nodes[3], 100000);
 103         let path = route.paths[0].clone();
 104         route.paths.push(path);
 105         route.paths[0][0].pubkey = nodes[1].node.get_our_node_id();
 106         route.paths[0][0].short_channel_id = chan_1_id;
 107         route.paths[0][1].short_channel_id = chan_3_id;
 108         route.paths[1][0].pubkey = nodes[2].node.get_our_node_id();
 109         route.paths[1][0].short_channel_id = chan_2_id;
 110         route.paths[1][1].short_channel_id = chan_4_id;
 111         send_along_route_with_secret(&nodes[0], route, &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], 200_000, payment_hash, payment_secret);
 112         fail_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_hash);
 113 }
 114
 115 #[test]
 116 fn mpp_retry() {
 117         let chanmon_cfgs = create_chanmon_cfgs(4);
 118         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 119         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 120         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 121
 122         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 123         let chan_2_id = create_announced_chan_between_nodes(&nodes, 0, 2, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 124         let chan_3_id = create_announced_chan_between_nodes(&nodes, 1, 3, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 125         let chan_4_id = create_announced_chan_between_nodes(&nodes, 3, 2, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 126         // Rebalance
 127         send_payment(&nodes[3], &vec!(&nodes[2])[..], 1_500_000);
 128
 129         let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[3], 1_000_000);
 130         let path = route.paths[0].clone();
 131         route.paths.push(path);
 132         route.paths[0][0].pubkey = nodes[1].node.get_our_node_id();
 133         route.paths[0][0].short_channel_id = chan_1_id;
 134         route.paths[0][1].short_channel_id = chan_3_id;
 135         route.paths[1][0].pubkey = nodes[2].node.get_our_node_id();
 136         route.paths[1][0].short_channel_id = chan_2_id;
 137         route.paths[1][1].short_channel_id = chan_4_id;
 138
 139         // Initiate the MPP payment.
 140         let payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
 141         check_added_monitors!(nodes[0], 2); // one monitor per path
 142         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 143         assert_eq!(events.len(), 2);
 144
 145         // Pass half of the payment along the success path.
 146         let success_path_msgs = events.remove(0);
 147         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 2_000_000, payment_hash, Some(payment_secret), success_path_msgs, false, None);
 148
 149         // Add the HTLC along the first hop.
 150         let fail_path_msgs_1 = events.remove(0);
 151         let (update_add, commitment_signed) = match fail_path_msgs_1 {
 152                 MessageSendEvent::UpdateHTLCs { node_id: _, updates: msgs::CommitmentUpdate { ref update_add_htlcs, ref update_fulfill_htlcs, ref update_fail_htlcs, ref update_fail_malformed_htlcs, ref update_fee, ref commitment_signed } } => {
 153                         assert_eq!(update_add_htlcs.len(), 1);
 154                         assert!(update_fail_htlcs.is_empty());
 155                         assert!(update_fulfill_htlcs.is_empty());
 156                         assert!(update_fail_malformed_htlcs.is_empty());
 157                         assert!(update_fee.is_none());
 158                         (update_add_htlcs[0].clone(), commitment_signed.clone())
 159                 },
 160                 _ => panic!("Unexpected event"),
 161         };
 162         nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add);
 163         commitment_signed_dance!(nodes[2], nodes[0], commitment_signed, false);
 164
 165         // Attempt to forward the payment and complete the 2nd path's failure.
 166         expect_pending_htlcs_forwardable!(&nodes[2]);
 167         expect_pending_htlcs_forwardable!(&nodes[2]);
 168         let htlc_updates = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id());
 169         assert!(htlc_updates.update_add_htlcs.is_empty());
 170         assert_eq!(htlc_updates.update_fail_htlcs.len(), 1);
 171         assert!(htlc_updates.update_fulfill_htlcs.is_empty());
 172         assert!(htlc_updates.update_fail_malformed_htlcs.is_empty());
 173         check_added_monitors!(nodes[2], 1);
 174         nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), &htlc_updates.update_fail_htlcs[0]);
 175         commitment_signed_dance!(nodes[0], nodes[2], htlc_updates.commitment_signed, false);
 176         expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain());
 177
 178         // Rebalance the channel so the second half of the payment can succeed.
 179         send_payment(&nodes[3], &vec!(&nodes[2])[..], 1_500_000);
 180
 181         // Make sure it errors as expected given a too-large amount.
 182         if let Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError { err })) = nodes[0].node.retry_payment(&route, payment_id) {
 183                 assert!(err.contains("over total_payment_amt_msat"));
 184         } else { panic!("Unexpected error"); }
 185
 186         // Make sure it errors as expected given the wrong payment_id.
 187         if let Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError { err })) = nodes[0].node.retry_payment(&route, PaymentId([0; 32])) {
 188                 assert!(err.contains("not found"));
 189         } else { panic!("Unexpected error"); }
 190
 191         // Retry the second half of the payment and make sure it succeeds.
 192         let mut path = route.clone();
 193         path.paths.remove(0);
 194         nodes[0].node.retry_payment(&path, payment_id).unwrap();
 195         check_added_monitors!(nodes[0], 1);
 196         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 197         assert_eq!(events.len(), 1);
 198         pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 2_000_000, payment_hash, Some(payment_secret), events.pop().unwrap(), true, None);
 199         claim_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_preimage);
 200 }
 201
 202 fn do_mpp_receive_timeout(send_partial_mpp: bool) {
 203         let chanmon_cfgs = create_chanmon_cfgs(4);
 204         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 205         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 206         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 207
 208         let chan_1_id = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 209         let chan_2_id = create_announced_chan_between_nodes(&nodes, 0, 2, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 210         let chan_3_id = create_announced_chan_between_nodes(&nodes, 1, 3, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 211         let chan_4_id = create_announced_chan_between_nodes(&nodes, 2, 3, InitFeatures::known(), InitFeatures::known()).0.contents.short_channel_id;
 212
 213         let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[3], 100_000);
 214         let path = route.paths[0].clone();
 215         route.paths.push(path);
 216         route.paths[0][0].pubkey = nodes[1].node.get_our_node_id();
 217         route.paths[0][0].short_channel_id = chan_1_id;
 218         route.paths[0][1].short_channel_id = chan_3_id;
 219         route.paths[1][0].pubkey = nodes[2].node.get_our_node_id();
 220         route.paths[1][0].short_channel_id = chan_2_id;
 221         route.paths[1][1].short_channel_id = chan_4_id;
 222
 223         // Initiate the MPP payment.
 224         let _ = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
 225         check_added_monitors!(nodes[0], 2); // one monitor per path
 226         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 227         assert_eq!(events.len(), 2);
 228
 229         // Pass half of the payment along the first path.
 230         pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 200_000, payment_hash, Some(payment_secret), events.remove(0), false, None);
 231
 232         if send_partial_mpp {
 233                 // Time out the partial MPP
 234                 for _ in 0..MPP_TIMEOUT_TICKS {
 235                         nodes[3].node.timer_tick_occurred();
 236                 }
 237
 238                 // Failed HTLC from node 3 -> 1
 239                 expect_pending_htlcs_forwardable!(nodes[3]);
 240                 let htlc_fail_updates_3_1 = get_htlc_update_msgs!(nodes[3], nodes[1].node.get_our_node_id());
 241                 assert_eq!(htlc_fail_updates_3_1.update_fail_htlcs.len(), 1);
 242                 nodes[1].node.handle_update_fail_htlc(&nodes[3].node.get_our_node_id(), &htlc_fail_updates_3_1.update_fail_htlcs[0]);
 243                 check_added_monitors!(nodes[3], 1);
 244                 commitment_signed_dance!(nodes[1], nodes[3], htlc_fail_updates_3_1.commitment_signed, false);
 245
 246                 // Failed HTLC from node 1 -> 0
 247                 expect_pending_htlcs_forwardable!(nodes[1]);
 248                 let htlc_fail_updates_1_0 = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 249                 assert_eq!(htlc_fail_updates_1_0.update_fail_htlcs.len(), 1);
 250                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_fail_updates_1_0.update_fail_htlcs[0]);
 251                 check_added_monitors!(nodes[1], 1);
 252                 commitment_signed_dance!(nodes[0], nodes[1], htlc_fail_updates_1_0.commitment_signed, false);
 253
 254                 expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain().expected_htlc_error_data(23, &[][..]));
 255         } else {
 256                 // Pass half of the payment along the second path.
 257                 pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 200_000, payment_hash, Some(payment_secret), events.remove(0), true, None);
 258
 259                 // Even after MPP_TIMEOUT_TICKS we should not timeout the MPP if we have all the parts
 260                 for _ in 0..MPP_TIMEOUT_TICKS {
 261                         nodes[3].node.timer_tick_occurred();
 262                 }
 263
 264                 claim_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_preimage);
 265         }
 266 }
 267
 268 #[test]
 269 fn mpp_receive_timeout() {
 270         do_mpp_receive_timeout(true);
 271         do_mpp_receive_timeout(false);
 272 }
 273
 274 #[test]
 275 fn retry_expired_payment() {
 276         let chanmon_cfgs = create_chanmon_cfgs(3);
 277         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 278         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 279         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 280
 281         let _chan_0 = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 282         let _chan_1 = create_announced_chan_between_nodes(&nodes, 2, 1, InitFeatures::known(), InitFeatures::known());
 283         // Rebalance to find a route
 284         send_payment(&nodes[2], &vec!(&nodes[1])[..], 3_000_000);
 285
 286         let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], 100_000);
 287
 288         // Rebalance so that the first hop fails.
 289         send_payment(&nodes[1], &vec!(&nodes[2])[..], 2_000_000);
 290
 291         // Make sure the payment fails on the first hop.
 292         let payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
 293         check_added_monitors!(nodes[0], 1);
 294         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 295         assert_eq!(events.len(), 1);
 296         let mut payment_event = SendEvent::from_event(events.pop().unwrap());
 297         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 298         check_added_monitors!(nodes[1], 0);
 299         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false);
 300         expect_pending_htlcs_forwardable!(nodes[1]);
 301         expect_pending_htlcs_forwardable!(&nodes[1]);
 302         let htlc_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 303         assert!(htlc_updates.update_add_htlcs.is_empty());
 304         assert_eq!(htlc_updates.update_fail_htlcs.len(), 1);
 305         assert!(htlc_updates.update_fulfill_htlcs.is_empty());
 306         assert!(htlc_updates.update_fail_malformed_htlcs.is_empty());
 307         check_added_monitors!(nodes[1], 1);
 308         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_updates.update_fail_htlcs[0]);
 309         commitment_signed_dance!(nodes[0], nodes[1], htlc_updates.commitment_signed, false);
 310         expect_payment_failed!(nodes[0], payment_hash, false);
 311
 312         // Mine blocks so the payment will have expired.
 313         connect_blocks(&nodes[0], 3);
 314
 315         // Retry the payment and make sure it errors as expected.
 316         if let Err(PaymentSendFailure::ParameterError(APIError::APIMisuseError { err })) = nodes[0].node.retry_payment(&route, payment_id) {
 317                 assert!(err.contains("not found"));
 318         } else {
 319                 panic!("Unexpected error");
 320         }
 321 }
 322
 323 #[test]
 324 fn no_pending_leak_on_initial_send_failure() {
 325         // In an earlier version of our payment tracking, we'd have a retry entry even when the initial
 326         // HTLC for payment failed to send due to local channel errors (e.g. peer disconnected). In this
 327         // case, the user wouldn't have a PaymentId to retry the payment with, but we'd think we have a
 328         // pending payment forever and never time it out.
 329         // Here we test exactly that - retrying a payment when a peer was disconnected on the first
 330         // try, and then check that no pending payment is being tracked.
 331         let chanmon_cfgs = create_chanmon_cfgs(2);
 332         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 333         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 334         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 335
 336         create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 337
 338         let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[1], 100_000);
 339
 340         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
 341         nodes[1].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
 342
 343         unwrap_send_err!(nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)),
 344                 true, APIError::ChannelUnavailable { ref err },
 345                 assert_eq!(err, "Peer for first hop currently disconnected/pending monitor update!"));
 346
 347         assert!(!nodes[0].node.has_pending_payments());
 348 }
 349
 350 fn do_retry_with_no_persist(confirm_before_reload: bool) {
 351         // If we send a pending payment and `send_payment` returns success, we should always either
 352         // return a payment failure event or a payment success event, and on failure the payment should
 353         // be retryable.
 354         //
 355         // In order to do so when the ChannelManager isn't immediately persisted (which is normal - its
 356         // always persisted asynchronously), the ChannelManager has to reload some payment data from
 357         // ChannelMonitor(s) in some cases. This tests that reloading.
 358         //
 359         // `confirm_before_reload` confirms the channel-closing commitment transaction on-chain prior
 360         // to reloading the ChannelManager, increasing test coverage in ChannelMonitor HTLC tracking
 361         // which has separate codepaths for "commitment transaction already confirmed" and not.
 362         let chanmon_cfgs = create_chanmon_cfgs(3);
 363         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 364         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 365         let persister: test_utils::TestPersister;
 366         let new_chain_monitor: test_utils::TestChainMonitor;
 367         let nodes_0_deserialized: ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>;
 368         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 369
 370         let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).2;
 371         let (_, _, chan_id_2, _) = create_announced_chan_between_nodes(&nodes, 1, 2, InitFeatures::known(), InitFeatures::known());
 372
 373         // Serialize the ChannelManager prior to sending payments
 374         let nodes_0_serialized = nodes[0].node.encode();
 375
 376         // Send two payments - one which will get to nodes[2] and will be claimed, one which we'll time
 377         // out and retry.
 378         let (route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
 379         let (payment_preimage_1, payment_hash_1, _, payment_id_1) = send_along_route(&nodes[0], route.clone(), &[&nodes[1], &nodes[2]], 1_000_000);
 380         let payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
 381         check_added_monitors!(nodes[0], 1);
 382
 383         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 384         assert_eq!(events.len(), 1);
 385         let payment_event = SendEvent::from_event(events.pop().unwrap());
 386         assert_eq!(payment_event.node_id, nodes[1].node.get_our_node_id());
 387
 388         // We relay the payment to nodes[1] while its disconnected from nodes[2], causing the payment
 389         // to be returned immediately to nodes[0], without having nodes[2] fail the inbound payment
 390         // which would prevent retry.
 391         nodes[1].node.peer_disconnected(&nodes[2].node.get_our_node_id(), false);
 392         nodes[2].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
 393
 394         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 395         commitment_signed_dance!(nodes[1], nodes[0], payment_event.commitment_msg, false, true);
 396         // nodes[1] now immediately fails the HTLC as the next-hop channel is disconnected
 397         let _ = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 398
 399         reconnect_nodes(&nodes[1], &nodes[2], (false, false), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
 400
 401         let as_commitment_tx = get_local_commitment_txn!(nodes[0], chan_id)[0].clone();
 402         if confirm_before_reload {
 403                 mine_transaction(&nodes[0], &as_commitment_tx);
 404                 nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 405         }
 406
 407         // The ChannelMonitor should always be the latest version, as we're required to persist it
 408         // during the `commitment_signed_dance!()`.
 409         let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
 410         get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
 411
 412         persister = test_utils::TestPersister::new();
 413         let keys_manager = &chanmon_cfgs[0].keys_manager;
 414         new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[0].chain_source), nodes[0].tx_broadcaster.clone(), nodes[0].logger, node_cfgs[0].fee_estimator, &persister, keys_manager);
 415         nodes[0].chain_monitor = &new_chain_monitor;
 416         let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
 417         let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
 418                 &mut chan_0_monitor_read, keys_manager).unwrap();
 419         assert!(chan_0_monitor_read.is_empty());
 420
 421         let mut nodes_0_read = &nodes_0_serialized[..];
 422         let (_, nodes_0_deserialized_tmp) = {
 423                 let mut channel_monitors = HashMap::new();
 424                 channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
 425                 <(BlockHash, ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
 426                         default_config: test_default_channel_config(),
 427                         keys_manager,
 428                         fee_estimator: node_cfgs[0].fee_estimator,
 429                         chain_monitor: nodes[0].chain_monitor,
 430                         tx_broadcaster: nodes[0].tx_broadcaster.clone(),
 431                         logger: nodes[0].logger,
 432                         channel_monitors,
 433                 }).unwrap()
 434         };
 435         nodes_0_deserialized = nodes_0_deserialized_tmp;
 436         assert!(nodes_0_read.is_empty());
 437
 438         assert!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor).is_ok());
 439         nodes[0].node = &nodes_0_deserialized;
 440         check_added_monitors!(nodes[0], 1);
 441
 442         // On reload, the ChannelManager should realize it is stale compared to the ChannelMonitor and
 443         // force-close the channel.
 444         check_closed_event!(nodes[0], 1, ClosureReason::OutdatedChannelManager);
 445         assert!(nodes[0].node.list_channels().is_empty());
 446         assert!(nodes[0].node.has_pending_payments());
 447         let as_broadcasted_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 448         assert_eq!(as_broadcasted_txn.len(), 1);
 449         assert_eq!(as_broadcasted_txn[0], as_commitment_tx);
 450
 451         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
 452         nodes[0].node.peer_connected(&nodes[1].node.get_our_node_id(), &msgs::Init { features: InitFeatures::known(), remote_network_address: None });
 453         assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
 454
 455         // Now nodes[1] should send a channel reestablish, which nodes[0] will respond to with an
 456         // error, as the channel has hit the chain.
 457         nodes[1].node.peer_connected(&nodes[0].node.get_our_node_id(), &msgs::Init { features: InitFeatures::known(), remote_network_address: None });
 458         let bs_reestablish = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id());
 459         nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 460         let as_err = nodes[0].node.get_and_clear_pending_msg_events();
 461         assert_eq!(as_err.len(), 1);
 462         match as_err[0] {
 463                 MessageSendEvent::HandleError { node_id, action: msgs::ErrorAction::SendErrorMessage { ref msg } } => {
 464                         assert_eq!(node_id, nodes[1].node.get_our_node_id());
 465                         nodes[1].node.handle_error(&nodes[0].node.get_our_node_id(), msg);
 466                         check_closed_event!(nodes[1], 1, ClosureReason::CounterpartyForceClosed { peer_msg: "Failed to find corresponding channel".to_string() });
 467                         check_added_monitors!(nodes[1], 1);
 468                         assert_eq!(nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0).len(), 1);
 469                 },
 470                 _ => panic!("Unexpected event"),
 471         }
 472         check_closed_broadcast!(nodes[1], false);
 473
 474         // Now claim the first payment, which should allow nodes[1] to claim the payment on-chain when
 475         // we close in a moment.
 476         nodes[2].node.claim_funds(payment_preimage_1);
 477         check_added_monitors!(nodes[2], 1);
 478         expect_payment_claimed!(nodes[2], payment_hash_1, 1_000_000);
 479
 480         let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[2], nodes[1].node.get_our_node_id());
 481         nodes[1].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
 482         check_added_monitors!(nodes[1], 1);
 483         commitment_signed_dance!(nodes[1], nodes[2], htlc_fulfill_updates.commitment_signed, false);
 484
 485         if confirm_before_reload {
 486                 let best_block = nodes[0].blocks.lock().unwrap().last().unwrap().clone();
 487                 nodes[0].node.best_block_updated(&best_block.0.header, best_block.1);
 488         }
 489
 490         // Create a new channel on which to retry the payment before we fail the payment via the
 491         // HTLC-Timeout transaction. This avoids ChannelManager timing out the payment due to us
 492         // connecting several blocks while creating the channel (implying time has passed).
 493         create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 494         assert_eq!(nodes[0].node.list_usable_channels().len(), 1);
 495
 496         mine_transaction(&nodes[1], &as_commitment_tx);
 497         let bs_htlc_claim_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 498         assert_eq!(bs_htlc_claim_txn.len(), 1);
 499         check_spends!(bs_htlc_claim_txn[0], as_commitment_tx);
 500         expect_payment_forwarded!(nodes[1], nodes[0], nodes[2], None, false, false);
 501
 502         if !confirm_before_reload {
 503                 mine_transaction(&nodes[0], &as_commitment_tx);
 504         }
 505         mine_transaction(&nodes[0], &bs_htlc_claim_txn[0]);
 506         expect_payment_sent!(nodes[0], payment_preimage_1);
 507         connect_blocks(&nodes[0], TEST_FINAL_CLTV*4 + 20);
 508         let as_htlc_timeout_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 509         assert_eq!(as_htlc_timeout_txn.len(), 3);
 510         let (first_htlc_timeout_tx, second_htlc_timeout_tx) = if as_htlc_timeout_txn[0] == as_commitment_tx {
 511                 (&as_htlc_timeout_txn[1], &as_htlc_timeout_txn[2])
 512         } else {
 513                 assert_eq!(as_htlc_timeout_txn[2], as_commitment_tx);
 514                 (&as_htlc_timeout_txn[0], &as_htlc_timeout_txn[1])
 515         };
 516         check_spends!(first_htlc_timeout_tx, as_commitment_tx);
 517         check_spends!(second_htlc_timeout_tx, as_commitment_tx);
 518         if first_htlc_timeout_tx.input[0].previous_output == bs_htlc_claim_txn[0].input[0].previous_output {
 519                 confirm_transaction(&nodes[0], &second_htlc_timeout_tx);
 520         } else {
 521                 confirm_transaction(&nodes[0], &first_htlc_timeout_tx);
 522         }
 523         nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().clear();
 524         expect_payment_failed_conditions(&nodes[0], payment_hash, false, PaymentFailedConditions::new().mpp_parts_remain());
 525
 526         // Finally, retry the payment (which was reloaded from the ChannelMonitor when nodes[0] was
 527         // reloaded) via a route over the new channel, which work without issue and eventually be
 528         // received and claimed at the recipient just like any other payment.
 529         let (mut new_route, _, _, _) = get_route_and_payment_hash!(nodes[0], nodes[2], 1_000_000);
 530
 531         // Update the fee on the middle hop to ensure PaymentSent events have the correct (retried) fee
 532         // and not the original fee. We also update node[1]'s relevant config as
 533         // do_claim_payment_along_route expects us to never overpay.
 534         nodes[1].node.channel_state.lock().unwrap().by_id.get_mut(&chan_id_2).unwrap().config.forwarding_fee_base_msat += 100_000;
 535         new_route.paths[0][0].fee_msat += 100_000;
 536
 537         assert!(nodes[0].node.retry_payment(&new_route, payment_id_1).is_err()); // Shouldn't be allowed to retry a fulfilled payment
 538         nodes[0].node.retry_payment(&new_route, payment_id).unwrap();
 539         check_added_monitors!(nodes[0], 1);
 540         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 541         assert_eq!(events.len(), 1);
 542         pass_along_path(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000, payment_hash, Some(payment_secret), events.pop().unwrap(), true, None);
 543         do_claim_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[2]]], false, payment_preimage);
 544         expect_payment_sent!(nodes[0], payment_preimage, Some(new_route.paths[0][0].fee_msat));
 545 }
 546
 547 #[test]
 548 fn retry_with_no_persist() {
 549         do_retry_with_no_persist(true);
 550         do_retry_with_no_persist(false);
 551 }
 552
 553 fn do_test_dup_htlc_onchain_fails_on_reload(persist_manager_post_event: bool, confirm_commitment_tx: bool, payment_timeout: bool) {
 554         // When a Channel is closed, any outbound HTLCs which were relayed through it are simply
 555         // dropped when the Channel is. From there, the ChannelManager relies on the ChannelMonitor
 556         // having a copy of the relevant fail-/claim-back data and processes the HTLC fail/claim when
 557         // the ChannelMonitor tells it to.
 558         //
 559         // If, due to an on-chain event, an HTLC is failed/claimed, we should avoid providing the
 560         // ChannelManager the HTLC event until after the monitor is re-persisted. This should prevent a
 561         // duplicate HTLC fail/claim (e.g. via a PaymentPathFailed event).
 562         let chanmon_cfgs = create_chanmon_cfgs(2);
 563         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 564         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 565         let persister: test_utils::TestPersister;
 566         let new_chain_monitor: test_utils::TestChainMonitor;
 567         let nodes_0_deserialized: ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>;
 568         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 569
 570         let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 571
 572         // Route a payment, but force-close the channel before the HTLC fulfill message arrives at
 573         // nodes[0].
 574         let (payment_preimage, payment_hash, _) = route_payment(&nodes[0], &[&nodes[1]], 10_000_000);
 575         nodes[0].node.force_close_channel(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
 576         check_closed_broadcast!(nodes[0], true);
 577         check_added_monitors!(nodes[0], 1);
 578         check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed);
 579
 580         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
 581         nodes[1].node.peer_disconnected(&nodes[0].node.get_our_node_id(), false);
 582
 583         // Connect blocks until the CLTV timeout is up so that we get an HTLC-Timeout transaction
 584         connect_blocks(&nodes[0], TEST_FINAL_CLTV + LATENCY_GRACE_PERIOD_BLOCKS + 1);
 585         let node_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 586         assert_eq!(node_txn.len(), 3);
 587         assert_eq!(node_txn[0], node_txn[1]);
 588         check_spends!(node_txn[1], funding_tx);
 589         check_spends!(node_txn[2], node_txn[1]);
 590         let timeout_txn = vec![node_txn[2].clone()];
 591
 592         nodes[1].node.claim_funds(payment_preimage);
 593         check_added_monitors!(nodes[1], 1);
 594         expect_payment_claimed!(nodes[1], payment_hash, 10_000_000);
 595
 596         let mut header = BlockHeader { version: 0x20000000, prev_blockhash: nodes[1].best_block_hash(), merkle_root: Default::default(), time: 42, bits: 42, nonce: 42 };
 597         connect_block(&nodes[1], &Block { header, txdata: vec![node_txn[1].clone()]});
 598         check_closed_broadcast!(nodes[1], true);
 599         check_added_monitors!(nodes[1], 1);
 600         check_closed_event!(nodes[1], 1, ClosureReason::CommitmentTxConfirmed);
 601         let claim_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 602         assert_eq!(claim_txn.len(), 3);
 603         check_spends!(claim_txn[0], node_txn[1]);
 604         check_spends!(claim_txn[1], funding_tx);
 605         check_spends!(claim_txn[2], claim_txn[1]);
 606
 607         header.prev_blockhash = nodes[0].best_block_hash();
 608         connect_block(&nodes[0], &Block { header, txdata: vec![node_txn[1].clone()]});
 609
 610         if confirm_commitment_tx {
 611                 connect_blocks(&nodes[0], BREAKDOWN_TIMEOUT as u32 - 1);
 612         }
 613
 614         header.prev_blockhash = nodes[0].best_block_hash();
 615         let claim_block = Block { header, txdata: if payment_timeout { timeout_txn } else { vec![claim_txn[0].clone()] } };
 616
 617         if payment_timeout {
 618                 assert!(confirm_commitment_tx); // Otherwise we're spending below our CSV!
 619                 connect_block(&nodes[0], &claim_block);
 620                 connect_blocks(&nodes[0], ANTI_REORG_DELAY - 2);
 621         }
 622
 623         // Now connect the HTLC claim transaction with the ChainMonitor-generated ChannelMonitor update
 624         // returning TemporaryFailure. This should cause the claim event to never make its way to the
 625         // ChannelManager.
 626         chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap().clear();
 627         chanmon_cfgs[0].persister.set_update_ret(Err(ChannelMonitorUpdateErr::TemporaryFailure));
 628
 629         if payment_timeout {
 630                 connect_blocks(&nodes[0], 1);
 631         } else {
 632                 connect_block(&nodes[0], &claim_block);
 633         }
 634
 635         let funding_txo = OutPoint { txid: funding_tx.txid(), index: 0 };
 636         let mon_updates: Vec<_> = chanmon_cfgs[0].persister.chain_sync_monitor_persistences.lock().unwrap()
 637                 .get_mut(&funding_txo).unwrap().drain().collect();
 638         // If we are using chain::Confirm instead of chain::Listen, we will get the same update twice
 639         assert!(mon_updates.len() == 1 || mon_updates.len() == 2);
 640         assert!(nodes[0].chain_monitor.release_pending_monitor_events().is_empty());
 641         assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
 642
 643         // If we persist the ChannelManager here, we should get the PaymentSent event after
 644         // deserialization.
 645         let mut chan_manager_serialized = test_utils::TestVecWriter(Vec::new());
 646         if !persist_manager_post_event {
 647                 nodes[0].node.write(&mut chan_manager_serialized).unwrap();
 648         }
 649
 650         // Now persist the ChannelMonitor and inform the ChainMonitor that we're done, generating the
 651         // payment sent event.
 652         chanmon_cfgs[0].persister.set_update_ret(Ok(()));
 653         let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
 654         get_monitor!(nodes[0], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
 655         for update in mon_updates {
 656                 nodes[0].chain_monitor.chain_monitor.channel_monitor_updated(funding_txo, update).unwrap();
 657         }
 658         if payment_timeout {
 659                 expect_payment_failed!(nodes[0], payment_hash, true);
 660         } else {
 661                 expect_payment_sent!(nodes[0], payment_preimage);
 662         }
 663
 664         // If we persist the ChannelManager after we get the PaymentSent event, we shouldn't get it
 665         // twice.
 666         if persist_manager_post_event {
 667                 nodes[0].node.write(&mut chan_manager_serialized).unwrap();
 668         }
 669
 670         // Now reload nodes[0]...
 671         persister = test_utils::TestPersister::new();
 672         let keys_manager = &chanmon_cfgs[0].keys_manager;
 673         new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[0].chain_source), nodes[0].tx_broadcaster.clone(), nodes[0].logger, node_cfgs[0].fee_estimator, &persister, keys_manager);
 674         nodes[0].chain_monitor = &new_chain_monitor;
 675         let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
 676         let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
 677                 &mut chan_0_monitor_read, keys_manager).unwrap();
 678         assert!(chan_0_monitor_read.is_empty());
 679
 680         let (_, nodes_0_deserialized_tmp) = {
 681                 let mut channel_monitors = HashMap::new();
 682                 channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
 683                 <(BlockHash, ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>
 684                         ::read(&mut io::Cursor::new(&chan_manager_serialized.0[..]), ChannelManagerReadArgs {
 685                                 default_config: Default::default(),
 686                                 keys_manager,
 687                                 fee_estimator: node_cfgs[0].fee_estimator,
 688                                 chain_monitor: nodes[0].chain_monitor,
 689                                 tx_broadcaster: nodes[0].tx_broadcaster.clone(),
 690                                 logger: nodes[0].logger,
 691                                 channel_monitors,
 692                         }).unwrap()
 693         };
 694         nodes_0_deserialized = nodes_0_deserialized_tmp;
 695
 696         assert!(nodes[0].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor).is_ok());
 697         check_added_monitors!(nodes[0], 1);
 698         nodes[0].node = &nodes_0_deserialized;
 699
 700         if persist_manager_post_event {
 701                 assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
 702         } else if payment_timeout {
 703                 expect_payment_failed!(nodes[0], payment_hash, true);
 704         } else {
 705                 expect_payment_sent!(nodes[0], payment_preimage);
 706         }
 707
 708         // Note that if we re-connect the block which exposed nodes[0] to the payment preimage (but
 709         // which the current ChannelMonitor has not seen), the ChannelManager's de-duplication of
 710         // payment events should kick in, leaving us with no pending events here.
 711         let height = nodes[0].blocks.lock().unwrap().len() as u32 - 1;
 712         nodes[0].chain_monitor.chain_monitor.block_connected(&claim_block, height);
 713         assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
 714 }
 715
 716 #[test]
 717 fn test_dup_htlc_onchain_fails_on_reload() {
 718         do_test_dup_htlc_onchain_fails_on_reload(true, true, true);
 719         do_test_dup_htlc_onchain_fails_on_reload(true, true, false);
 720         do_test_dup_htlc_onchain_fails_on_reload(true, false, false);
 721         do_test_dup_htlc_onchain_fails_on_reload(false, true, true);
 722         do_test_dup_htlc_onchain_fails_on_reload(false, true, false);
 723         do_test_dup_htlc_onchain_fails_on_reload(false, false, false);
 724 }
 725
 726 #[test]
 727 fn test_fulfill_restart_failure() {
 728         // When we receive an update_fulfill_htlc message, we immediately consider the HTLC fully
 729         // fulfilled. At this point, the peer can reconnect and decide to either fulfill the HTLC
 730         // again, or fail it, giving us free money.
 731         //
 732         // Of course probably they won't fail it and give us free money, but because we have code to
 733         // handle it, we should test the logic for it anyway. We do that here.
 734         let chanmon_cfgs = create_chanmon_cfgs(2);
 735         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 736         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 737         let persister: test_utils::TestPersister;
 738         let new_chain_monitor: test_utils::TestChainMonitor;
 739         let nodes_1_deserialized: ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>;
 740         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 741
 742         let chan_id = create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known()).2;
 743         let (payment_preimage, payment_hash, _) = route_payment(&nodes[0], &[&nodes[1]], 100_000);
 744
 745         // The simplest way to get a failure after a fulfill is to reload nodes[1] from a state
 746         // pre-fulfill, which we do by serializing it here.
 747         let mut chan_manager_serialized = test_utils::TestVecWriter(Vec::new());
 748         nodes[1].node.write(&mut chan_manager_serialized).unwrap();
 749         let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
 750         get_monitor!(nodes[1], chan_id).write(&mut chan_0_monitor_serialized).unwrap();
 751
 752         nodes[1].node.claim_funds(payment_preimage);
 753         check_added_monitors!(nodes[1], 1);
 754         expect_payment_claimed!(nodes[1], payment_hash, 100_000);
 755
 756         let htlc_fulfill_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 757         nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &htlc_fulfill_updates.update_fulfill_htlcs[0]);
 758         expect_payment_sent_without_paths!(nodes[0], payment_preimage);
 759
 760         // Now reload nodes[1]...
 761         persister = test_utils::TestPersister::new();
 762         let keys_manager = &chanmon_cfgs[1].keys_manager;
 763         new_chain_monitor = test_utils::TestChainMonitor::new(Some(nodes[1].chain_source), nodes[1].tx_broadcaster.clone(), nodes[1].logger, node_cfgs[1].fee_estimator, &persister, keys_manager);
 764         nodes[1].chain_monitor = &new_chain_monitor;
 765         let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
 766         let (_, mut chan_0_monitor) = <(BlockHash, ChannelMonitor<EnforcingSigner>)>::read(
 767                 &mut chan_0_monitor_read, keys_manager).unwrap();
 768         assert!(chan_0_monitor_read.is_empty());
 769
 770         let (_, nodes_1_deserialized_tmp) = {
 771                 let mut channel_monitors = HashMap::new();
 772                 channel_monitors.insert(chan_0_monitor.get_funding_txo().0, &mut chan_0_monitor);
 773                 <(BlockHash, ChannelManager<EnforcingSigner, &test_utils::TestChainMonitor, &test_utils::TestBroadcaster, &test_utils::TestKeysInterface, &test_utils::TestFeeEstimator, &test_utils::TestLogger>)>
 774                         ::read(&mut io::Cursor::new(&chan_manager_serialized.0[..]), ChannelManagerReadArgs {
 775                                 default_config: Default::default(),
 776                                 keys_manager,
 777                                 fee_estimator: node_cfgs[1].fee_estimator,
 778                                 chain_monitor: nodes[1].chain_monitor,
 779                                 tx_broadcaster: nodes[1].tx_broadcaster.clone(),
 780                                 logger: nodes[1].logger,
 781                                 channel_monitors,
 782                         }).unwrap()
 783         };
 784         nodes_1_deserialized = nodes_1_deserialized_tmp;
 785
 786         assert!(nodes[1].chain_monitor.watch_channel(chan_0_monitor.get_funding_txo().0, chan_0_monitor).is_ok());
 787         check_added_monitors!(nodes[1], 1);
 788         nodes[1].node = &nodes_1_deserialized;
 789
 790         nodes[0].node.peer_disconnected(&nodes[1].node.get_our_node_id(), false);
 791         reconnect_nodes(&nodes[0], &nodes[1], (false, false), (0, 0), (0, 0), (0, 0), (0, 0), (0, 0), (false, false));
 792
 793         nodes[1].node.fail_htlc_backwards(&payment_hash);
 794         expect_pending_htlcs_forwardable!(nodes[1]);
 795         check_added_monitors!(nodes[1], 1);
 796         let htlc_fail_updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 797         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &htlc_fail_updates.update_fail_htlcs[0]);
 798         commitment_signed_dance!(nodes[0], nodes[1], htlc_fail_updates.commitment_signed, false);
 799         // nodes[0] shouldn't generate any events here, while it just got a payment failure completion
 800         // it had already considered the payment fulfilled, and now they just got free money.
 801         assert!(nodes[0].node.get_and_clear_pending_events().is_empty());
 802 }
 803
 804 #[test]
 805 fn get_ldk_payment_preimage() {
 806         // Ensure that `ChannelManager::get_payment_preimage` can successfully be used to claim a payment.
 807         let chanmon_cfgs = create_chanmon_cfgs(2);
 808         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 809         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 810         let mut nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 811         create_announced_chan_between_nodes(&nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
 812
 813         let amt_msat = 60_000;
 814         let expiry_secs = 60 * 60;
 815         let (payment_hash, payment_secret) = nodes[1].node.create_inbound_payment(Some(amt_msat), expiry_secs).unwrap();
 816
 817         let payment_params = PaymentParameters::from_node_id(nodes[1].node.get_our_node_id())
 818                 .with_features(InvoiceFeatures::known());
 819         let scorer = test_utils::TestScorer::with_penalty(0);
 820         let keys_manager = test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
 821         let random_seed_bytes = keys_manager.get_secure_random_bytes();
 822         let route = get_route(
 823                 &nodes[0].node.get_our_node_id(), &payment_params, &nodes[0].network_graph.read_only(),
 824                 Some(&nodes[0].node.list_usable_channels().iter().collect::<Vec<_>>()),
 825                 amt_msat, TEST_FINAL_CLTV, nodes[0].logger, &scorer, &random_seed_bytes).unwrap();
 826         let _payment_id = nodes[0].node.send_payment(&route, payment_hash, &Some(payment_secret)).unwrap();
 827         check_added_monitors!(nodes[0], 1);
 828
 829         // Make sure to use `get_payment_preimage`
 830         let payment_preimage = nodes[1].node.get_payment_preimage(payment_hash, payment_secret).unwrap();
 831         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 832         assert_eq!(events.len(), 1);
 833         pass_along_path(&nodes[0], &[&nodes[1]], amt_msat, payment_hash, Some(payment_secret), events.pop().unwrap(), true, Some(payment_preimage));
 834         claim_payment_along_route(&nodes[0], &[&[&nodes[1]]], false, payment_preimage);
 835 }