From 6765767cbc2b8e4a8fbe04c4a2b2e982809f5604 Mon Sep 17 00:00:00 2001 From: Elias Rohrer Date: Tue, 26 Sep 2023 15:30:39 +0200 Subject: [PATCH] Test `max_total_routing_fee_msat` handling when retrying overpaid paths We setup an MPP scenario with two paths in which we need to overpay to reach `htlc_minimum_msat`. We then fail the overpaid path and check that on retry our `max_total_routing_fee_msat` only accounts for the path fees, but not for the fees overpaid in the first attempt. --- lightning/src/ln/payment_tests.rs | 136 ++++++++++++++++++++++++++++++ 1 file changed, 136 insertions(+) diff --git a/lightning/src/ln/payment_tests.rs b/lightning/src/ln/payment_tests.rs index 2833ba8e..94c3bf66 100644 --- a/lightning/src/ln/payment_tests.rs +++ b/lightning/src/ln/payment_tests.rs @@ -166,6 +166,142 @@ fn mpp_retry() { claim_payment_along_route(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_preimage); } +#[test] +fn mpp_retry_overpay() { + // We create an MPP scenario with two paths in which we need to overpay to reach + // htlc_minimum_msat. We then fail the overpaid path and check that on retry our + // max_total_routing_fee_msat only accounts for the path's fees, but not for the fees overpaid + // in the first attempt. + let chanmon_cfgs = create_chanmon_cfgs(4); + let node_cfgs = create_node_cfgs(4, &chanmon_cfgs); + let mut user_config = test_default_channel_config(); + user_config.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 100; + let mut limited_config_1 = user_config.clone(); + limited_config_1.channel_handshake_config.our_htlc_minimum_msat = 35_000_000; + let mut limited_config_2 = user_config.clone(); + limited_config_2.channel_handshake_config.our_htlc_minimum_msat = 34_500_000; + let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, + &[Some(user_config), Some(limited_config_1), Some(limited_config_2), Some(user_config)]); + let nodes = create_network(4, &node_cfgs, &node_chanmgrs); + + let (chan_1_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 0, 1, 40_000, 0); + let (chan_2_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 40_000, 0); + let (_chan_3_update, _, _, _) = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 40_000, 0); + let (chan_4_update, _, chan_4_id, _) = create_announced_chan_between_nodes_with_value(&nodes, 3, 2, 40_000, 0); + + let amt_msat = 70_000_000; + let max_total_routing_fee_msat = Some(1_000_000); + + let payment_params = PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV) + .with_bolt11_features(nodes[3].node.invoice_features()).unwrap(); + let (mut route, payment_hash, payment_preimage, payment_secret) = get_route_and_payment_hash!( + nodes[0], nodes[3], payment_params, amt_msat, max_total_routing_fee_msat); + + // Check we overpay on the second path which we're about to fail. + assert_eq!(chan_1_update.contents.fee_proportional_millionths, 0); + let overpaid_amount_1 = route.paths[0].fee_msat() as u32 - chan_1_update.contents.fee_base_msat; + assert_eq!(overpaid_amount_1, 0); + + assert_eq!(chan_2_update.contents.fee_proportional_millionths, 0); + let overpaid_amount_2 = route.paths[1].fee_msat() as u32 - chan_2_update.contents.fee_base_msat; + + let total_overpaid_amount = overpaid_amount_1 + overpaid_amount_2; + + // Initiate the payment. + let payment_id = PaymentId(payment_hash.0); + let mut route_params = route.route_params.clone().unwrap(); + + nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone())); + nodes[0].node.send_payment(payment_hash, RecipientOnionFields::secret_only(payment_secret), + payment_id, route_params.clone(), Retry::Attempts(1)).unwrap(); + check_added_monitors!(nodes[0], 2); // one monitor per path + let mut events = nodes[0].node.get_and_clear_pending_msg_events(); + assert_eq!(events.len(), 2); + + // Pass half of the payment along the success path. + let success_path_msgs = remove_first_msg_event_to_node(&nodes[1].node.get_our_node_id(), &mut events); + pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], amt_msat, payment_hash, + Some(payment_secret), success_path_msgs, false, None); + + // Add the HTLC along the first hop. + let fail_path_msgs_1 = remove_first_msg_event_to_node(&nodes[2].node.get_our_node_id(), &mut events); + let (update_add, commitment_signed) = match fail_path_msgs_1 { + 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 + } + } => { + assert_eq!(update_add_htlcs.len(), 1); + assert!(update_fail_htlcs.is_empty()); + assert!(update_fulfill_htlcs.is_empty()); + assert!(update_fail_malformed_htlcs.is_empty()); + assert!(update_fee.is_none()); + (update_add_htlcs[0].clone(), commitment_signed.clone()) + }, + _ => panic!("Unexpected event"), + }; + nodes[2].node.handle_update_add_htlc(&nodes[0].node.get_our_node_id(), &update_add); + commitment_signed_dance!(nodes[2], nodes[0], commitment_signed, false); + + // Attempt to forward the payment and complete the 2nd path's failure. + expect_pending_htlcs_forwardable!(&nodes[2]); + expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[2], + vec![HTLCDestination::NextHopChannel { + node_id: Some(nodes[3].node.get_our_node_id()), channel_id: chan_4_id + }] + ); + let htlc_updates = get_htlc_update_msgs!(nodes[2], nodes[0].node.get_our_node_id()); + assert!(htlc_updates.update_add_htlcs.is_empty()); + assert_eq!(htlc_updates.update_fail_htlcs.len(), 1); + assert!(htlc_updates.update_fulfill_htlcs.is_empty()); + assert!(htlc_updates.update_fail_malformed_htlcs.is_empty()); + check_added_monitors!(nodes[2], 1); + nodes[0].node.handle_update_fail_htlc(&nodes[2].node.get_our_node_id(), + &htlc_updates.update_fail_htlcs[0]); + commitment_signed_dance!(nodes[0], nodes[2], htlc_updates.commitment_signed, false); + let mut events = nodes[0].node.get_and_clear_pending_events(); + match events[1] { + Event::PendingHTLCsForwardable { .. } => {}, + _ => panic!("Unexpected event") + } + events.remove(1); + expect_payment_failed_conditions_event(events, payment_hash, false, + PaymentFailedConditions::new().mpp_parts_remain()); + + // Rebalance the channel so the second half of the payment can succeed. + send_payment(&nodes[3], &vec!(&nodes[2])[..], 38_000_000); + + // Retry the second half of the payment and make sure it succeeds. + let first_path_value = route.paths[0].final_value_msat(); + assert_eq!(first_path_value, 36_000_000); + + route.paths.remove(0); + route_params.final_value_msat -= first_path_value; + route_params.payment_params.previously_failed_channels.push(chan_4_update.contents.short_channel_id); + + // Check the remaining max total routing fee for the second attempt accounts only for 1_000 msat + // base fee, but not for overpaid value of the first try. + route_params.max_total_routing_fee_msat.as_mut().map(|m| *m -= 1000); + nodes[0].router.expect_find_route(route_params, Ok(route)); + nodes[0].node.process_pending_htlc_forwards(); + + check_added_monitors!(nodes[0], 1); + let mut events = nodes[0].node.get_and_clear_pending_msg_events(); + assert_eq!(events.len(), 1); + pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], amt_msat, payment_hash, + Some(payment_secret), events.pop().unwrap(), true, None); + + // Can't use claim_payment_along_route as it doesn't support overpayment, so we break out the + // individual steps here. + let extra_fees = vec![0, total_overpaid_amount]; + let expected_total_fee_msat = do_claim_payment_along_route_with_extra_penultimate_hop_fees( + &nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], &extra_fees[..], false, + payment_preimage); + expect_payment_sent!(&nodes[0], payment_preimage, Some(expected_total_fee_msat)); +} + fn do_mpp_receive_timeout(send_partial_mpp: bool) { let chanmon_cfgs = create_chanmon_cfgs(4); let node_cfgs = create_node_cfgs(4, &chanmon_cfgs); -- 2.30.2