_ Git - rust-lightning/blob - lightning/src/ln/blinded_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 use bitcoin::secp256k1::{PublicKey, Secp256k1, SecretKey};
  11 use crate::blinded_path::BlindedPath;
  12 use crate::blinded_path::payment::{ForwardNode, ForwardTlvs, PaymentConstraints, PaymentRelay, ReceiveTlvs};
  13 use crate::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, PaymentFailureReason};
  14 use crate::ln::PaymentSecret;
  15 use crate::ln::channelmanager;
  16 use crate::ln::channelmanager::{PaymentId, RecipientOnionFields};
  17 use crate::ln::features::BlindedHopFeatures;
  18 use crate::ln::functional_test_utils::*;
  19 use crate::ln::msgs;
  20 use crate::ln::msgs::ChannelMessageHandler;
  21 use crate::ln::onion_utils;
  22 use crate::ln::onion_utils::INVALID_ONION_BLINDING;
  23 use crate::ln::outbound_payment::Retry;
  24 use crate::offers::invoice::BlindedPayInfo;
  25 use crate::prelude::*;
  26 use crate::routing::router::{Payee, PaymentParameters, RouteParameters};
  27 use crate::util::config::UserConfig;
  28 use crate::util::test_utils;
  29
  30 fn blinded_payment_path(
  31         payment_secret: PaymentSecret, node_ids: Vec<PublicKey>,
  32         channel_upds: &[&msgs::UnsignedChannelUpdate], keys_manager: &test_utils::TestKeysInterface
  33 ) -> (BlindedPayInfo, BlindedPath) {
  34         let mut intermediate_nodes = Vec::new();
  35         for (node_id, chan_upd) in node_ids.iter().zip(channel_upds) {
  36                 intermediate_nodes.push(ForwardNode {
  37                         node_id: *node_id,
  38                         tlvs: ForwardTlvs {
  39                                 short_channel_id: chan_upd.short_channel_id,
  40                                 payment_relay: PaymentRelay {
  41                                         cltv_expiry_delta: chan_upd.cltv_expiry_delta,
  42                                         fee_proportional_millionths: chan_upd.fee_proportional_millionths,
  43                                         fee_base_msat: chan_upd.fee_base_msat,
  44                                 },
  45                                 payment_constraints: PaymentConstraints {
  46                                         max_cltv_expiry: u32::max_value(),
  47                                         htlc_minimum_msat: chan_upd.htlc_minimum_msat,
  48                                 },
  49                                 features: BlindedHopFeatures::empty(),
  50                         },
  51                         htlc_maximum_msat: chan_upd.htlc_maximum_msat,
  52                 });
  53         }
  54         let payee_tlvs = ReceiveTlvs {
  55                 payment_secret,
  56                 payment_constraints: PaymentConstraints {
  57                         max_cltv_expiry: u32::max_value(),
  58                         htlc_minimum_msat: channel_upds.last().unwrap().htlc_minimum_msat,
  59                 },
  60         };
  61         let mut secp_ctx = Secp256k1::new();
  62         BlindedPath::new_for_payment(
  63                 &intermediate_nodes[..], *node_ids.last().unwrap(), payee_tlvs,
  64                 channel_upds.last().unwrap().htlc_maximum_msat, keys_manager, &secp_ctx
  65         ).unwrap()
  66 }
  67
  68 pub fn get_blinded_route_parameters(
  69         amt_msat: u64, payment_secret: PaymentSecret, node_ids: Vec<PublicKey>,
  70         channel_upds: &[&msgs::UnsignedChannelUpdate], keys_manager: &test_utils::TestKeysInterface
  71 ) -> RouteParameters {
  72         RouteParameters::from_payment_params_and_value(
  73                 PaymentParameters::blinded(vec![
  74                         blinded_payment_path(payment_secret, node_ids, channel_upds, keys_manager)
  75                 ]), amt_msat
  76         )
  77 }
  78
  79 #[test]
  80 fn one_hop_blinded_path() {
  81         do_one_hop_blinded_path(true);
  82         do_one_hop_blinded_path(false);
  83 }
  84
  85 fn do_one_hop_blinded_path(success: bool) {
  86         let chanmon_cfgs = create_chanmon_cfgs(2);
  87         let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
  88         let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
  89         let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
  90         let chan_upd = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0).0.contents;
  91
  92         let amt_msat = 5000;
  93         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[1], Some(amt_msat), None);
  94         let payee_tlvs = ReceiveTlvs {
  95                 payment_secret,
  96                 payment_constraints: PaymentConstraints {
  97                         max_cltv_expiry: u32::max_value(),
  98                         htlc_minimum_msat: chan_upd.htlc_minimum_msat,
  99                 },
 100         };
 101         let mut secp_ctx = Secp256k1::new();
 102         let blinded_path = BlindedPath::one_hop_for_payment(
 103                 nodes[1].node.get_our_node_id(), payee_tlvs, &chanmon_cfgs[1].keys_manager, &secp_ctx
 104         ).unwrap();
 105
 106         let route_params = RouteParameters::from_payment_params_and_value(
 107                 PaymentParameters::blinded(vec![blinded_path]),
 108                 amt_msat,
 109         );
 110         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(),
 111         PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 112         check_added_monitors(&nodes[0], 1);
 113         pass_along_route(&nodes[0], &[&[&nodes[1]]], amt_msat, payment_hash, payment_secret);
 114         if success {
 115                 claim_payment(&nodes[0], &[&nodes[1]], payment_preimage);
 116         } else {
 117                 fail_payment(&nodes[0], &[&nodes[1]], payment_hash);
 118         }
 119 }
 120
 121 #[test]
 122 fn mpp_to_one_hop_blinded_path() {
 123         let chanmon_cfgs = create_chanmon_cfgs(4);
 124         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 125         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
 126         let nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 127         let mut secp_ctx = Secp256k1::new();
 128
 129         create_announced_chan_between_nodes(&nodes, 0, 1);
 130         create_announced_chan_between_nodes(&nodes, 0, 2);
 131         let chan_upd_1_3 = create_announced_chan_between_nodes(&nodes, 1, 3).0.contents;
 132         create_announced_chan_between_nodes(&nodes, 2, 3).0.contents;
 133
 134         let amt_msat = 15_000_000;
 135         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[3], Some(amt_msat), None);
 136         let payee_tlvs = ReceiveTlvs {
 137                 payment_secret,
 138                 payment_constraints: PaymentConstraints {
 139                         max_cltv_expiry: u32::max_value(),
 140                         htlc_minimum_msat: chan_upd_1_3.htlc_minimum_msat,
 141                 },
 142         };
 143         let blinded_path = BlindedPath::one_hop_for_payment(
 144                 nodes[3].node.get_our_node_id(), payee_tlvs, &chanmon_cfgs[3].keys_manager, &secp_ctx
 145         ).unwrap();
 146
 147         let bolt12_features =
 148                 channelmanager::provided_bolt12_invoice_features(&UserConfig::default());
 149         let route_params = RouteParameters::from_payment_params_and_value(
 150                 PaymentParameters::blinded(vec![blinded_path]).with_bolt12_features(bolt12_features).unwrap(),
 151                 amt_msat,
 152         );
 153         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 154         check_added_monitors(&nodes[0], 2);
 155
 156         let expected_route: &[&[&Node]] = &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]];
 157         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 158         assert_eq!(events.len(), 2);
 159
 160         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 161         pass_along_path(&nodes[0], expected_route[0], amt_msat, payment_hash.clone(),
 162                 Some(payment_secret), ev.clone(), false, None);
 163
 164         let ev = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 165         pass_along_path(&nodes[0], expected_route[1], amt_msat, payment_hash.clone(),
 166                 Some(payment_secret), ev.clone(), true, None);
 167         claim_payment_along_route(&nodes[0], expected_route, false, payment_preimage);
 168 }
 169
 170 enum ForwardCheckFail {
 171         // Fail a check on the inbound onion payload. In this case, we underflow when calculating the
 172         // outgoing cltv_expiry.
 173         InboundOnionCheck,
 174         // The forwarding node's payload is encoded as a receive, i.e. the next hop HMAC is [0; 32].
 175         ForwardPayloadEncodedAsReceive,
 176         // Fail a check on the outbound channel. In this case, our next-hop peer is offline.
 177         OutboundChannelCheck,
 178 }
 179
 180 #[test]
 181 fn forward_checks_failure() {
 182         do_forward_checks_failure(ForwardCheckFail::InboundOnionCheck);
 183         do_forward_checks_failure(ForwardCheckFail::ForwardPayloadEncodedAsReceive);
 184         do_forward_checks_failure(ForwardCheckFail::OutboundChannelCheck);
 185 }
 186
 187 fn do_forward_checks_failure(check: ForwardCheckFail) {
 188         // Ensure we'll fail backwards properly if a forwarding check fails on initial update_add
 189         // receipt.
 190         let chanmon_cfgs = create_chanmon_cfgs(3);
 191         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 192         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 193         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 194         // We need the session priv to construct a bogus onion packet later.
 195         *nodes[0].keys_manager.override_random_bytes.lock().unwrap() = Some([3; 32]);
 196         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 197         let chan_upd_1_2 = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0).0.contents;
 198
 199         let amt_msat = 5000;
 200         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 201         let route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 202                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&chan_upd_1_2],
 203                 &chanmon_cfgs[2].keys_manager);
 204
 205         let route = get_route(&nodes[0], &route_params).unwrap();
 206         node_cfgs[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
 207         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 208         check_added_monitors(&nodes[0], 1);
 209
 210         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 211         assert_eq!(events.len(), 1);
 212         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 213         let mut payment_event = SendEvent::from_event(ev);
 214
 215         let mut update_add = &mut payment_event.msgs[0];
 216         match check {
 217                 ForwardCheckFail::InboundOnionCheck => {
 218                         update_add.cltv_expiry = 10; // causes outbound CLTV expiry to underflow
 219                 },
 220                 ForwardCheckFail::ForwardPayloadEncodedAsReceive => {
 221                         let session_priv = SecretKey::from_slice(&[3; 32]).unwrap();
 222                         let onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route.paths[0], &session_priv).unwrap();
 223                         let cur_height = nodes[0].best_block_info().1;
 224                         let (mut onion_payloads, ..) = onion_utils::build_onion_payloads(
 225                                 &route.paths[0], amt_msat, RecipientOnionFields::spontaneous_empty(), cur_height, &None).unwrap();
 226                         // Remove the receive payload so the blinded forward payload is encoded as a final payload
 227                         // (i.e. next_hop_hmac == [0; 32])
 228                         onion_payloads.pop();
 229                         update_add.onion_routing_packet = onion_utils::construct_onion_packet(onion_payloads, onion_keys, [0; 32], &payment_hash).unwrap();
 230                 },
 231                 ForwardCheckFail::OutboundChannelCheck => {
 232                         // The intro node will see that the next-hop peer is disconnected and fail the HTLC backwards.
 233                         nodes[1].node.peer_disconnected(&nodes[2].node.get_our_node_id());
 234                 },
 235         }
 236         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 237         check_added_monitors!(nodes[1], 0);
 238         do_commitment_signed_dance(&nodes[1], &nodes[0], &payment_event.commitment_msg, true, true);
 239
 240         let mut updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 241         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
 242         do_commitment_signed_dance(&nodes[0], &nodes[1], &updates.commitment_signed, false, false);
 243         expect_payment_failed_conditions(&nodes[0], payment_hash, false,
 244                 PaymentFailedConditions::new().expected_htlc_error_data(INVALID_ONION_BLINDING, &[0; 32]));
 245 }
 246
 247 #[test]
 248 fn failed_backwards_to_intro_node() {
 249         // Ensure the intro node will error backwards properly even if the downstream node did not blind
 250         // their error.
 251         let chanmon_cfgs = create_chanmon_cfgs(3);
 252         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 253         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 254         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 255         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 256         let chan_upd_1_2 = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0).0.contents;
 257
 258         let amt_msat = 5000;
 259         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 260         let route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 261                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&chan_upd_1_2],
 262                 &chanmon_cfgs[2].keys_manager);
 263
 264         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 265         check_added_monitors(&nodes[0], 1);
 266
 267         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 268         assert_eq!(events.len(), 1);
 269         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 270         let mut payment_event = SendEvent::from_event(ev);
 271
 272         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 273         check_added_monitors!(nodes[1], 0);
 274         do_commitment_signed_dance(&nodes[1], &nodes[0], &payment_event.commitment_msg, false, false);
 275         expect_pending_htlcs_forwardable!(nodes[1]);
 276         check_added_monitors!(&nodes[1], 1);
 277
 278         let mut events = nodes[1].node.get_and_clear_pending_msg_events();
 279         assert_eq!(events.len(), 1);
 280         let ev = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 281         let mut payment_event = SendEvent::from_event(ev);
 282
 283         // Ensure the final node fails to handle the HTLC.
 284         payment_event.msgs[0].onion_routing_packet.hop_data[0] ^= 1;
 285         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event.msgs[0]);
 286         check_added_monitors!(nodes[2], 0);
 287         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event.commitment_msg, true, true);
 288         nodes[2].node.process_pending_htlc_forwards();
 289
 290         let mut updates = get_htlc_update_msgs!(nodes[2], nodes[1].node.get_our_node_id());
 291         let mut update_malformed = &mut updates.update_fail_malformed_htlcs[0];
 292         // Check that the final node encodes its failure correctly.
 293         assert_eq!(update_malformed.failure_code, INVALID_ONION_BLINDING);
 294         assert_eq!(update_malformed.sha256_of_onion, [0; 32]);
 295
 296         // Modify such the final hop does not correctly blind their error so we can ensure the intro node
 297         // converts it to the correct error.
 298         update_malformed.sha256_of_onion = [1; 32];
 299         nodes[1].node.handle_update_fail_malformed_htlc(&nodes[2].node.get_our_node_id(), update_malformed);
 300         do_commitment_signed_dance(&nodes[1], &nodes[2], &updates.commitment_signed, true, false);
 301
 302         let mut updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 303         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
 304         do_commitment_signed_dance(&nodes[0], &nodes[1], &updates.commitment_signed, false, false);
 305         expect_payment_failed_conditions(&nodes[0], payment_hash, false,
 306                 PaymentFailedConditions::new().expected_htlc_error_data(INVALID_ONION_BLINDING, &[0; 32]));
 307 }
 308
 309 enum ProcessPendingHTLCsCheck {
 310         FwdPeerDisconnected,
 311         FwdChannelClosed,
 312 }
 313
 314 #[test]
 315 fn forward_fail_in_process_pending_htlc_fwds() {
 316         do_forward_fail_in_process_pending_htlc_fwds(ProcessPendingHTLCsCheck::FwdPeerDisconnected);
 317         do_forward_fail_in_process_pending_htlc_fwds(ProcessPendingHTLCsCheck::FwdChannelClosed);
 318 }
 319 fn do_forward_fail_in_process_pending_htlc_fwds(check: ProcessPendingHTLCsCheck) {
 320         // Ensure the intro node will error backwards properly if the HTLC fails in
 321         // process_pending_htlc_forwards.
 322         let chanmon_cfgs = create_chanmon_cfgs(3);
 323         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 324         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 325         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 326         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 327         let (chan_upd_1_2, channel_id) = {
 328                 let chan = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0);
 329                 (chan.0.contents, chan.2)
 330         };
 331
 332         let amt_msat = 5000;
 333         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 334         let route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 335                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&chan_upd_1_2],
 336                 &chanmon_cfgs[2].keys_manager);
 337
 338         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 339         check_added_monitors(&nodes[0], 1);
 340
 341         let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 342         assert_eq!(events.len(), 1);
 343         let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 344         let mut payment_event = SendEvent::from_event(ev);
 345
 346         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 347         check_added_monitors!(nodes[1], 0);
 348         do_commitment_signed_dance(&nodes[1], &nodes[0], &payment_event.commitment_msg, false, false);
 349
 350         match check {
 351                 ProcessPendingHTLCsCheck::FwdPeerDisconnected => {
 352                         // Disconnect the next-hop peer so when we go to forward in process_pending_htlc_forwards, the
 353                         // intro node will error backwards.
 354                         nodes[1].node.peer_disconnected(&nodes[2].node.get_our_node_id());
 355                         expect_pending_htlcs_forwardable!(nodes[1]);
 356                         expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[1],
 357                                 vec![HTLCDestination::NextHopChannel { node_id: Some(nodes[2].node.get_our_node_id()), channel_id }]);
 358                 },
 359                 ProcessPendingHTLCsCheck::FwdChannelClosed => {
 360                         // Force close the next-hop channel so when we go to forward in process_pending_htlc_forwards,
 361                         // the intro node will error backwards.
 362                         nodes[1].node.force_close_broadcasting_latest_txn(&channel_id, &nodes[2].node.get_our_node_id()).unwrap();
 363                         let events = nodes[1].node.get_and_clear_pending_events();
 364                         match events[0] {
 365                                 crate::events::Event::PendingHTLCsForwardable { .. } => {},
 366                                 _ => panic!("Unexpected event {:?}", events),
 367                         };
 368                         match events[1] {
 369                                 crate::events::Event::ChannelClosed { .. } => {},
 370                                 _ => panic!("Unexpected event {:?}", events),
 371                         }
 372
 373                         nodes[1].node.process_pending_htlc_forwards();
 374                         expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[1],
 375                                 vec![HTLCDestination::UnknownNextHop { requested_forward_scid: chan_upd_1_2.short_channel_id }]);
 376                         check_closed_broadcast(&nodes[1], 1, true);
 377                         check_added_monitors!(nodes[1], 1);
 378                         nodes[1].node.process_pending_htlc_forwards();
 379                 },
 380         }
 381
 382         let mut updates = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 383         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fail_htlcs[0]);
 384         check_added_monitors!(nodes[1], 1);
 385         do_commitment_signed_dance(&nodes[0], &nodes[1], &updates.commitment_signed, false, false);
 386
 387         expect_payment_failed_conditions(&nodes[0], payment_hash, false,
 388                 PaymentFailedConditions::new().expected_htlc_error_data(INVALID_ONION_BLINDING, &[0; 32]));
 389 }
 390
 391 #[test]
 392 fn blinded_intercept_payment() {
 393         do_blinded_intercept_payment(true);
 394         do_blinded_intercept_payment(false);
 395 }
 396 fn do_blinded_intercept_payment(intercept_node_fails: bool) {
 397         let chanmon_cfgs = create_chanmon_cfgs(3);
 398         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 399         let mut intercept_forwards_config = test_default_channel_config();
 400         intercept_forwards_config.accept_intercept_htlcs = true;
 401         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, Some(intercept_forwards_config), None]);
 402         let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 403         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 404         let (channel_id, chan_upd) = {
 405                 let chan = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0);
 406                 (chan.2, chan.0.contents)
 407         };
 408
 409         let amt_msat = 5000;
 410         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 411         let intercept_scid = nodes[1].node.get_intercept_scid();
 412         let mut intercept_chan_upd = chan_upd;
 413         intercept_chan_upd.short_channel_id = intercept_scid;
 414         let route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 415                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&intercept_chan_upd],
 416                 &chanmon_cfgs[2].keys_manager);
 417
 418         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(),
 419         PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 420         check_added_monitors(&nodes[0], 1);
 421         let payment_event = {
 422                 let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 423                 assert_eq!(events.len(), 1);
 424                 SendEvent::from_event(events.remove(0))
 425         };
 426         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event.msgs[0]);
 427         commitment_signed_dance!(nodes[1], nodes[0], &payment_event.commitment_msg, false, true);
 428
 429         let events = nodes[1].node.get_and_clear_pending_events();
 430         assert_eq!(events.len(), 1);
 431         let (intercept_id, expected_outbound_amount_msat) = match events[0] {
 432                 crate::events::Event::HTLCIntercepted {
 433                         intercept_id, payment_hash: pmt_hash,
 434                         requested_next_hop_scid: short_channel_id, expected_outbound_amount_msat, ..
 435                 } => {
 436                         assert_eq!(pmt_hash, payment_hash);
 437                         assert_eq!(short_channel_id, intercept_scid);
 438                         (intercept_id, expected_outbound_amount_msat)
 439                 },
 440                 _ => panic!()
 441         };
 442
 443         if intercept_node_fails {
 444                 nodes[1].node.fail_intercepted_htlc(intercept_id).unwrap();
 445                 expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[1], vec![HTLCDestination::UnknownNextHop { requested_forward_scid: intercept_scid }]);
 446                 nodes[1].node.process_pending_htlc_forwards();
 447                 let update_fail = get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id());
 448                 check_added_monitors!(&nodes[1], 1);
 449                 assert!(update_fail.update_fail_htlcs.len() == 1);
 450                 let fail_msg = update_fail.update_fail_htlcs[0].clone();
 451                 nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &fail_msg);
 452                 commitment_signed_dance!(nodes[0], nodes[1], update_fail.commitment_signed, false);
 453                 expect_payment_failed_conditions(&nodes[0], payment_hash, false,
 454                         PaymentFailedConditions::new().expected_htlc_error_data(INVALID_ONION_BLINDING, &[0; 32]));
 455                 return
 456         }
 457
 458         nodes[1].node.forward_intercepted_htlc(intercept_id, &channel_id, nodes[2].node.get_our_node_id(), expected_outbound_amount_msat).unwrap();
 459         expect_pending_htlcs_forwardable!(nodes[1]);
 460
 461         let payment_event = {
 462                 {
 463                         let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 464                         assert_eq!(added_monitors.len(), 1);
 465                         added_monitors.clear();
 466                 }
 467                 let mut events = nodes[1].node.get_and_clear_pending_msg_events();
 468                 assert_eq!(events.len(), 1);
 469                 SendEvent::from_event(events.remove(0))
 470         };
 471         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event.msgs[0]);
 472         commitment_signed_dance!(nodes[2], nodes[1], &payment_event.commitment_msg, false, true);
 473         expect_pending_htlcs_forwardable!(nodes[2]);
 474
 475         expect_payment_claimable!(&nodes[2], payment_hash, payment_secret, amt_msat, None, nodes[2].node.get_our_node_id());
 476         do_claim_payment_along_route(&nodes[0], &vec!(&vec!(&nodes[1], &nodes[2])[..]), false, payment_preimage);
 477         expect_payment_sent(&nodes[0], payment_preimage, Some(Some(1000)), true, true);
 478 }
 479
 480 #[test]
 481 fn two_hop_blinded_path_success() {
 482         let chanmon_cfgs = create_chanmon_cfgs(3);
 483         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 484         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 485         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 486         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 487         let chan_upd_1_2 = create_announced_chan_between_nodes_with_value(&nodes, 1, 2, 1_000_000, 0).0.contents;
 488
 489         let amt_msat = 5000;
 490         let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 491         let route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 492                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&chan_upd_1_2],
 493                 &chanmon_cfgs[2].keys_manager);
 494
 495         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 496         check_added_monitors(&nodes[0], 1);
 497         pass_along_route(&nodes[0], &[&[&nodes[1], &nodes[2]]], amt_msat, payment_hash, payment_secret);
 498         claim_payment(&nodes[0], &[&nodes[1], &nodes[2]], payment_preimage);
 499 }
 500
 501 #[derive(PartialEq)]
 502 enum ReceiveCheckFail {
 503         // The recipient fails the payment upon `PaymentClaimable`.
 504         RecipientFail,
 505         // Failure to decode the recipient's onion payload.
 506         OnionDecodeFail,
 507         // The incoming HTLC did not satisfy our requirements; in this case it underpaid us according to
 508         // the expected receive amount in the onion.
 509         ReceiveRequirements,
 510         // The incoming HTLC errors when added to the Channel, in this case due to the HTLC being
 511         // delivered out-of-order with a shutdown message.
 512         ChannelCheck,
 513         // The HTLC is successfully added to the inbound channel but fails receive checks in
 514         // process_pending_htlc_forwards.
 515         ProcessPendingHTLCsCheck,
 516         // The HTLC violates the `PaymentConstraints` contained within the receiver's encrypted payload.
 517         PaymentConstraints,
 518 }
 519
 520 #[test]
 521 fn multi_hop_receiver_fail() {
 522         do_multi_hop_receiver_fail(ReceiveCheckFail::RecipientFail);
 523         do_multi_hop_receiver_fail(ReceiveCheckFail::OnionDecodeFail);
 524         do_multi_hop_receiver_fail(ReceiveCheckFail::ReceiveRequirements);
 525         do_multi_hop_receiver_fail(ReceiveCheckFail::ChannelCheck);
 526         do_multi_hop_receiver_fail(ReceiveCheckFail::ProcessPendingHTLCsCheck);
 527         do_multi_hop_receiver_fail(ReceiveCheckFail::PaymentConstraints);
 528 }
 529
 530 fn do_multi_hop_receiver_fail(check: ReceiveCheckFail) {
 531         // Test that the receiver to a multihop blinded path fails back correctly.
 532         let chanmon_cfgs = create_chanmon_cfgs(3);
 533         let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
 534         let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
 535         let mut nodes = create_network(3, &node_cfgs, &node_chanmgrs);
 536         // We need the session priv to construct an invalid onion packet later.
 537         let session_priv = [3; 32];
 538         *nodes[0].keys_manager.override_random_bytes.lock().unwrap() = Some(session_priv);
 539         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 540         let (chan_upd_1_2, chan_id_1_2) = {
 541                 let (chan_upd, _, channel_id, ..) = create_announced_chan_between_nodes_with_value(
 542                         &nodes, 1, 2, 1_000_000, 0
 543                 );
 544                 (chan_upd.contents, channel_id)
 545         };
 546
 547         let amt_msat = 5000;
 548         let final_cltv_delta = if check == ReceiveCheckFail::ProcessPendingHTLCsCheck {
 549                 // Set the final CLTV expiry too low to trigger the failure in process_pending_htlc_forwards.
 550                 Some(TEST_FINAL_CLTV as u16 - 2)
 551         } else { None };
 552         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), final_cltv_delta);
 553         let mut route_params = get_blinded_route_parameters(amt_msat, payment_secret,
 554                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&chan_upd_1_2],
 555                 &chanmon_cfgs[2].keys_manager);
 556
 557         let route = if check == ReceiveCheckFail::ProcessPendingHTLCsCheck {
 558                 let mut route = get_route(&nodes[0], &route_params).unwrap();
 559                 // Set the final CLTV expiry too low to trigger the failure in process_pending_htlc_forwards.
 560                 route.paths[0].blinded_tail.as_mut().map(|bt| bt.excess_final_cltv_expiry_delta = TEST_FINAL_CLTV - 2);
 561                 route
 562         } else if check == ReceiveCheckFail::PaymentConstraints {
 563                 // Create a blinded path where the receiver's encrypted payload has an htlc_minimum_msat that is
 564                 // violated by `amt_msat`, and stick it in the route_params without changing the corresponding
 565                 // BlindedPayInfo (to ensure pathfinding still succeeds).
 566                 let high_htlc_min_bp = {
 567                         let mut high_htlc_minimum_upd = chan_upd_1_2.clone();
 568                         high_htlc_minimum_upd.htlc_minimum_msat = amt_msat + 1000;
 569                         let high_htlc_min_params = get_blinded_route_parameters(amt_msat, payment_secret,
 570                                 nodes.iter().skip(1).map(|n| n.node.get_our_node_id()).collect(), &[&high_htlc_minimum_upd],
 571                                 &chanmon_cfgs[2].keys_manager);
 572                         if let Payee::Blinded { route_hints, .. } = high_htlc_min_params.payment_params.payee {
 573                                 route_hints[0].1.clone()
 574                         } else { panic!() }
 575                 };
 576                 if let Payee::Blinded { ref mut route_hints, .. } = route_params.payment_params.payee {
 577                         route_hints[0].1 = high_htlc_min_bp;
 578                 } else { panic!() }
 579                 find_route(&nodes[0], &route_params).unwrap()
 580         } else {
 581                 find_route(&nodes[0], &route_params).unwrap()
 582         };
 583         node_cfgs[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
 584         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params, Retry::Attempts(0)).unwrap();
 585         check_added_monitors(&nodes[0], 1);
 586
 587         let mut payment_event_0_1 = {
 588                 let mut events = nodes[0].node.get_and_clear_pending_msg_events();
 589                 assert_eq!(events.len(), 1);
 590                 let ev = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events);
 591                 SendEvent::from_event(ev)
 592         };
 593         nodes[1].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &payment_event_0_1.msgs[0]);
 594         check_added_monitors!(nodes[1], 0);
 595         do_commitment_signed_dance(&nodes[1], &nodes[0], &payment_event_0_1.commitment_msg, false, false);
 596         expect_pending_htlcs_forwardable!(nodes[1]);
 597         check_added_monitors!(&nodes[1], 1);
 598
 599         let mut payment_event_1_2 = {
 600                 let mut events = nodes[1].node.get_and_clear_pending_msg_events();
 601                 assert_eq!(events.len(), 1);
 602                 let ev = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events);
 603                 SendEvent::from_event(ev)
 604         };
 605
 606         match check {
 607                 ReceiveCheckFail::RecipientFail => {
 608                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event_1_2.msgs[0]);
 609                         check_added_monitors!(nodes[2], 0);
 610                         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true);
 611                         expect_pending_htlcs_forwardable!(nodes[2]);
 612                         check_payment_claimable(
 613                                 &nodes[2].node.get_and_clear_pending_events()[0], payment_hash, payment_secret, amt_msat,
 614                                 None, nodes[2].node.get_our_node_id()
 615                         );
 616                         nodes[2].node.fail_htlc_backwards(&payment_hash);
 617                         expect_pending_htlcs_forwardable_conditions(
 618                                 nodes[2].node.get_and_clear_pending_events(), &[HTLCDestination::FailedPayment { payment_hash }]
 619                         );
 620                         nodes[2].node.process_pending_htlc_forwards();
 621                         check_added_monitors!(nodes[2], 1);
 622                 },
 623                 ReceiveCheckFail::OnionDecodeFail => {
 624                         let session_priv = SecretKey::from_slice(&session_priv).unwrap();
 625                         let mut onion_keys = onion_utils::construct_onion_keys(&Secp256k1::new(), &route.paths[0], &session_priv).unwrap();
 626                         let cur_height = nodes[0].best_block_info().1;
 627                         let (mut onion_payloads, ..) = onion_utils::build_onion_payloads(
 628                                 &route.paths[0], amt_msat, RecipientOnionFields::spontaneous_empty(), cur_height, &None).unwrap();
 629
 630                         let update_add = &mut payment_event_1_2.msgs[0];
 631                         onion_payloads.last_mut().map(|p| {
 632                                 if let msgs::OutboundOnionPayload::BlindedReceive { ref mut intro_node_blinding_point, .. } = p {
 633                                         // The receiver should error if both the update_add blinding_point and the
 634                                         // intro_node_blinding_point are set.
 635                                         assert!(intro_node_blinding_point.is_none() && update_add.blinding_point.is_some());
 636                                         *intro_node_blinding_point = Some(PublicKey::from_slice(&[2; 33]).unwrap());
 637                                 } else { panic!() }
 638                         });
 639                         update_add.onion_routing_packet = onion_utils::construct_onion_packet(
 640                                 vec![onion_payloads.pop().unwrap()], vec![onion_keys.pop().unwrap()], [0; 32],
 641                                 &payment_hash
 642                         ).unwrap();
 643                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), update_add);
 644                         check_added_monitors!(nodes[2], 0);
 645                         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true);
 646                 },
 647                 ReceiveCheckFail::ReceiveRequirements => {
 648                         let update_add = &mut payment_event_1_2.msgs[0];
 649                         update_add.amount_msat -= 1;
 650                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), update_add);
 651                         check_added_monitors!(nodes[2], 0);
 652                         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true);
 653                 },
 654                 ReceiveCheckFail::ChannelCheck => {
 655                         nodes[2].node.close_channel(&chan_id_1_2, &nodes[1].node.get_our_node_id()).unwrap();
 656                         let node_2_shutdown = get_event_msg!(nodes[2], MessageSendEvent::SendShutdown, nodes[1].node.get_our_node_id());
 657                         nodes[1].node.handle_shutdown(&nodes[2].node.get_our_node_id(), &node_2_shutdown);
 658                         let node_1_shutdown = get_event_msg!(nodes[1], MessageSendEvent::SendShutdown, nodes[2].node.get_our_node_id());
 659
 660                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event_1_2.msgs[0]);
 661                         nodes[2].node.handle_commitment_signed(&nodes[1].node.get_our_node_id(), &payment_event_1_2.commitment_msg);
 662                         check_added_monitors!(nodes[2], 1);
 663
 664                         nodes[2].node.handle_shutdown(&nodes[1].node.get_our_node_id(), &node_1_shutdown);
 665                         commitment_signed_dance!(nodes[2], nodes[1], (), false, true, false, false);
 666                 },
 667                 ReceiveCheckFail::ProcessPendingHTLCsCheck => {
 668                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event_1_2.msgs[0]);
 669                         check_added_monitors!(nodes[2], 0);
 670                         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true);
 671                         expect_pending_htlcs_forwardable!(nodes[2]);
 672                         expect_pending_htlcs_forwardable_and_htlc_handling_failed_ignore!(nodes[2],
 673                                 vec![HTLCDestination::FailedPayment { payment_hash }]);
 674                         check_added_monitors!(nodes[2], 1);
 675                 },
 676                 ReceiveCheckFail::PaymentConstraints => {
 677                         nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event_1_2.msgs[0]);
 678                         check_added_monitors!(nodes[2], 0);
 679                         do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true);
 680                 }
 681         }
 682
 683         let updates_2_1 = get_htlc_update_msgs!(nodes[2], nodes[1].node.get_our_node_id());
 684         assert_eq!(updates_2_1.update_fail_malformed_htlcs.len(), 1);
 685         let update_malformed = &updates_2_1.update_fail_malformed_htlcs[0];
 686         assert_eq!(update_malformed.sha256_of_onion, [0; 32]);
 687         assert_eq!(update_malformed.failure_code, INVALID_ONION_BLINDING);
 688         nodes[1].node.handle_update_fail_malformed_htlc(&nodes[2].node.get_our_node_id(), update_malformed);
 689         do_commitment_signed_dance(&nodes[1], &nodes[2], &updates_2_1.commitment_signed, true, false);
 690
 691         let updates_1_0 = if check == ReceiveCheckFail::ChannelCheck {
 692                 let events = nodes[1].node.get_and_clear_pending_msg_events();
 693                 assert_eq!(events.len(), 2);
 694                 events.into_iter().find_map(|ev| {
 695                         match ev {
 696                                 MessageSendEvent:: UpdateHTLCs { node_id, updates } => {
 697                                         assert_eq!(node_id, nodes[0].node.get_our_node_id());
 698                                         return Some(updates)
 699                                 },
 700                                 MessageSendEvent::SendClosingSigned { .. } => None,
 701                                 _ => panic!()
 702                         }
 703                 }).unwrap()
 704         } else { get_htlc_update_msgs!(nodes[1], nodes[0].node.get_our_node_id()) };
 705         assert_eq!(updates_1_0.update_fail_htlcs.len(), 1);
 706         nodes[0].node.handle_update_fail_htlc(&nodes[1].node.get_our_node_id(), &updates_1_0.update_fail_htlcs[0]);
 707         do_commitment_signed_dance(&nodes[0], &nodes[1], &updates_1_0.commitment_signed, false, false);
 708         expect_payment_failed_conditions(&nodes[0], payment_hash, false,
 709                 PaymentFailedConditions::new().expected_htlc_error_data(INVALID_ONION_BLINDING, &[0; 32]));
 710 }
 711
 712 #[test]
 713 fn blinded_path_retries() {
 714         let chanmon_cfgs = create_chanmon_cfgs(4);
 715         // Make one blinded path's fees slightly higher so they are tried in a deterministic order.
 716         let mut higher_fee_chan_cfg = test_default_channel_config();
 717         higher_fee_chan_cfg.channel_config.forwarding_fee_base_msat += 1;
 718         let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
 719         let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, Some(higher_fee_chan_cfg), None]);
 720         let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);
 721
 722         // Create this network topology so nodes[0] has a blinded route hint to retry over.
 723         //      n1
 724         //    /    \
 725         // n0       n3
 726         //    \    /
 727         //      n2
 728         create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 1_000_000, 0);
 729         create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
 730         let chan_1_3 = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 1_000_000, 0);
 731         let chan_2_3 = create_announced_chan_between_nodes_with_value(&nodes, 2, 3, 1_000_000, 0);
 732
 733         let amt_msat = 5000;
 734         let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[3], Some(amt_msat), None);
 735         let route_params = {
 736                 let pay_params = PaymentParameters::blinded(
 737                         vec![
 738                                 blinded_payment_path(payment_secret,
 739                                         vec![nodes[1].node.get_our_node_id(), nodes[3].node.get_our_node_id()], &[&chan_1_3.0.contents],
 740                                         &chanmon_cfgs[3].keys_manager
 741                                 ),
 742                                 blinded_payment_path(payment_secret,
 743                                         vec![nodes[2].node.get_our_node_id(), nodes[3].node.get_our_node_id()], &[&chan_2_3.0.contents],
 744                                         &chanmon_cfgs[3].keys_manager
 745                                 ),
 746                         ]
 747                 )
 748                         .with_bolt12_features(channelmanager::provided_bolt12_invoice_features(&UserConfig::default()))
 749                         .unwrap();
 750                 RouteParameters::from_payment_params_and_value(pay_params, amt_msat)
 751         };
 752
 753         nodes[0].node.send_payment(payment_hash, RecipientOnionFields::spontaneous_empty(), PaymentId(payment_hash.0), route_params.clone(), Retry::Attempts(2)).unwrap();
 754         check_added_monitors(&nodes[0], 1);
 755         pass_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]]], amt_msat, payment_hash, payment_secret);
 756
 757         macro_rules! fail_payment_back {
 758                 ($intro_node: expr) => {
 759                         nodes[3].node.fail_htlc_backwards(&payment_hash);
 760                         expect_pending_htlcs_forwardable_conditions(
 761                                 nodes[3].node.get_and_clear_pending_events(), &[HTLCDestination::FailedPayment { payment_hash }]
 762                         );
 763                         nodes[3].node.process_pending_htlc_forwards();
 764                         check_added_monitors!(nodes[3], 1);
 765
 766                         let updates = get_htlc_update_msgs!(nodes[3], $intro_node.node.get_our_node_id());
 767                         assert_eq!(updates.update_fail_malformed_htlcs.len(), 1);
 768                         let update_malformed = &updates.update_fail_malformed_htlcs[0];
 769                         assert_eq!(update_malformed.sha256_of_onion, [0; 32]);
 770                         assert_eq!(update_malformed.failure_code, INVALID_ONION_BLINDING);
 771                         $intro_node.node.handle_update_fail_malformed_htlc(&nodes[3].node.get_our_node_id(), update_malformed);
 772                         do_commitment_signed_dance(&$intro_node, &nodes[3], &updates.commitment_signed, true, false);
 773
 774                         let updates =  get_htlc_update_msgs!($intro_node, nodes[0].node.get_our_node_id());
 775                         assert_eq!(updates.update_fail_htlcs.len(), 1);
 776                         nodes[0].node.handle_update_fail_htlc(&$intro_node.node.get_our_node_id(), &updates.update_fail_htlcs[0]);
 777                         do_commitment_signed_dance(&nodes[0], &$intro_node, &updates.commitment_signed, false, false);
 778
 779                         let mut events = nodes[0].node.get_and_clear_pending_events();
 780                         assert_eq!(events.len(), 2);
 781                         match events[0] {
 782                                 Event::PaymentPathFailed { payment_hash: ev_payment_hash, payment_failed_permanently, ..  } => {
 783                                         assert_eq!(payment_hash, ev_payment_hash);
 784                                         assert_eq!(payment_failed_permanently, false);
 785                                 },
 786                                 _ => panic!("Unexpected event"),
 787                         }
 788                         match events[1] {
 789                                 Event::PendingHTLCsForwardable { .. } => {},
 790                                 _ => panic!("Unexpected event"),
 791                         }
 792                         nodes[0].node.process_pending_htlc_forwards();
 793                 }
 794         }
 795
 796         fail_payment_back!(nodes[1]);
 797
 798         // Pass the retry along.
 799         check_added_monitors!(nodes[0], 1);
 800         let mut msg_events = nodes[0].node.get_and_clear_pending_msg_events();
 801         assert_eq!(msg_events.len(), 1);
 802         pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], amt_msat, payment_hash, Some(payment_secret), msg_events.pop().unwrap(), true, None);
 803
 804         fail_payment_back!(nodes[2]);
 805         let evs = nodes[0].node.get_and_clear_pending_events();
 806         assert_eq!(evs.len(), 1);
 807         match evs[0] {
 808                 Event::PaymentFailed { payment_hash: ev_payment_hash, reason, .. } => {
 809                         assert_eq!(ev_payment_hash, payment_hash);
 810                         // We have 1 retry attempt remaining, but we're out of blinded paths to try.
 811                         assert_eq!(reason, Some(PaymentFailureReason::RouteNotFound));
 812                 },
 813                 _ => panic!()
 814         }
 815 }