};
debug_assert!(!sources.is_empty());
- // If we are claiming an MPP payment, we check that all channels which contain a claimable
- // HTLC still exist. While this isn't guaranteed to remain true if a channel closes while
- // we're claiming (or even after we claim, before the commitment update dance completes),
- // it should be a relatively rare race, and we'd rather not claim HTLCs that require us to
- // go on-chain (and lose the on-chain fee to do so) than just reject the payment.
- //
- // Note that we'll still always get our funds - as long as the generated
- // `ChannelMonitorUpdate` makes it out to the relevant monitor we can claim on-chain.
- //
- // If we find an HTLC which we would need to claim but for which we do not have a
- // channel, we will fail all parts of the MPP payment. While we could wait and see if
- // the sender retries the already-failed path(s), it should be a pretty rare case where
- // we got all the HTLCs and then a channel closed while we were waiting for the user to
- // provide the preimage, so worrying too much about the optimal handling isn't worth
- // it.
+ // Just in case one HTLC has been failed between when we generated the `PaymentClaimable`
+ // and when we got here we need to check that the amount we're about to claim matches the
+ // amount we told the user in the last `PaymentClaimable`. We also do a sanity-check that
+ // the MPP parts all have the same `total_msat`.
let mut claimable_amt_msat = 0;
let mut prev_total_msat = None;
let mut expected_amt_msat = None;
let mut errs = Vec::new();
let per_peer_state = self.per_peer_state.read().unwrap();
for htlc in sources.iter() {
- let (counterparty_node_id, chan_id) = match self.short_to_chan_info.read().unwrap().get(&htlc.prev_hop.short_channel_id) {
- Some((cp_id, chan_id)) => (cp_id.clone(), chan_id.clone()),
- None => {
- valid_mpp = false;
- break;
- }
- };
-
- let peer_state_mutex_opt = per_peer_state.get(&counterparty_node_id);
- if peer_state_mutex_opt.is_none() {
- valid_mpp = false;
- break;
- }
-
- let mut peer_state_lock = peer_state_mutex_opt.unwrap().lock().unwrap();
- let peer_state = &mut *peer_state_lock;
-
- if peer_state.channel_by_id.get(&chan_id).is_none() {
- valid_mpp = false;
- break;
- }
-
if prev_total_msat.is_some() && prev_total_msat != Some(htlc.total_msat) {
log_error!(self.logger, "Somehow ended up with an MPP payment with different expected total amounts - this should not be reachable!");
debug_assert!(false);
//! payments thereafter.
use crate::chain::{ChannelMonitorUpdateStatus, Confirm, Listen, Watch};
-use crate::chain::channelmonitor::{ANTI_REORG_DELAY, LATENCY_GRACE_PERIOD_BLOCKS};
+use crate::chain::channelmonitor::{ANTI_REORG_DELAY, HTLC_FAIL_BACK_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS};
use crate::chain::keysinterface::EntropySource;
use crate::chain::transaction::OutPoint;
use crate::events::{ClosureReason, Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, PathFailure};
use crate::ln::msgs::ChannelMessageHandler;
use crate::ln::outbound_payment::Retry;
use crate::routing::gossip::{EffectiveCapacity, RoutingFees};
-use crate::routing::router::{get_route, PaymentParameters, Route, RouteHint, RouteHintHop, RouteHop, RouteParameters};
+use crate::routing::router::{get_route, PaymentParameters, Route, Router, RouteHint, RouteHintHop, RouteHop, RouteParameters};
use crate::routing::scoring::ChannelUsage;
use crate::util::test_utils;
use crate::util::errors::APIError;
do_no_missing_sent_on_midpoint_reload(false);
do_no_missing_sent_on_midpoint_reload(true);
}
+
+fn do_claim_from_closed_chan(fail_payment: bool) {
+ // Previously, LDK would refuse to claim a payment if a channel on which the payment was
+ // received had been closed between when the HTLC was received and when we went to claim it.
+ // This makes sense in the payment case - why pay an on-chain fee to claim the HTLC when
+ // presumably the sender may retry later. Long ago it also reduced total code in the claim
+ // pipeline.
+ //
+ // However, this doesn't make sense if you're trying to do an atomic swap or some other
+ // protocol that requires atomicity with some other action - if your money got claimed
+ // elsewhere you need to be able to claim the HTLC in lightning no matter what. Further, this
+ // is an over-optimization - there should be a very, very low likelihood that a channel closes
+ // between when we receive the last HTLC for a payment and the user goes to claim the payment.
+ // Since we now have code to handle this anyway we should allow it.
+
+ // Build 4 nodes and send an MPP payment across two paths. By building a route manually set the
+ // CLTVs on the paths to different value resulting in a different claim deadline.
+ let chanmon_cfgs = create_chanmon_cfgs(4);
+ let node_cfgs = create_node_cfgs(4, &chanmon_cfgs);
+ let node_chanmgrs = create_node_chanmgrs(4, &node_cfgs, &[None, None, None, None]);
+ let mut nodes = create_network(4, &node_cfgs, &node_chanmgrs);
+
+ create_announced_chan_between_nodes(&nodes, 0, 1);
+ create_announced_chan_between_nodes_with_value(&nodes, 0, 2, 1_000_000, 0);
+ let chan_bd = create_announced_chan_between_nodes_with_value(&nodes, 1, 3, 1_000_000, 0).2;
+ create_announced_chan_between_nodes(&nodes, 2, 3);
+
+ let (payment_preimage, payment_hash, payment_secret) = get_payment_preimage_hash!(nodes[3]);
+ let mut route_params = RouteParameters {
+ payment_params: PaymentParameters::from_node_id(nodes[3].node.get_our_node_id(), TEST_FINAL_CLTV)
+ .with_features(nodes[1].node.invoice_features()),
+ final_value_msat: 10_000_000,
+ };
+ let mut route = nodes[0].router.find_route(&nodes[0].node.get_our_node_id(), &route_params,
+ None, &nodes[0].node.compute_inflight_htlcs()).unwrap();
+ // Make sure the route is ordered as the B->D path before C->D
+ route.paths.sort_by(|a, _| if a[0].pubkey == nodes[1].node.get_our_node_id() {
+ std::cmp::Ordering::Less } else { std::cmp::Ordering::Greater });
+
+ // Note that we add an extra 1 in the send pipeline to compensate for any blocks found while
+ // the HTLC is being relayed.
+ route.paths[0][1].cltv_expiry_delta = TEST_FINAL_CLTV + 8;
+ route.paths[1][1].cltv_expiry_delta = TEST_FINAL_CLTV + 12;
+ let final_cltv = nodes[0].best_block_info().1 + TEST_FINAL_CLTV + 8 + 1;
+
+ nodes[0].router.expect_find_route(route_params.clone(), Ok(route.clone()));
+ nodes[0].node.send_payment_with_retry(payment_hash, &Some(payment_secret),
+ PaymentId(payment_hash.0), route_params.clone(), Retry::Attempts(1)).unwrap();
+ check_added_monitors(&nodes[0], 2);
+ let mut send_msgs = nodes[0].node.get_and_clear_pending_msg_events();
+ send_msgs.sort_by(|a, _| {
+ let a_node_id =
+ if let MessageSendEvent::UpdateHTLCs { node_id, .. } = a { node_id } else { panic!() };
+ let node_b_id = nodes[1].node.get_our_node_id();
+ if *a_node_id == node_b_id { std::cmp::Ordering::Less } else { std::cmp::Ordering::Greater }
+ });
+
+ assert_eq!(send_msgs.len(), 2);
+ pass_along_path(&nodes[0], &[&nodes[1], &nodes[3]], 10_000_000,
+ payment_hash, Some(payment_secret), send_msgs.remove(0), false, None);
+ pass_along_path(&nodes[0], &[&nodes[2], &nodes[3]], 10_000_000,
+ payment_hash, Some(payment_secret), send_msgs.remove(0), true, None);
+
+ // Ensure that the claim_deadline is correct, with the payment failing at exactly the given
+ // height.
+ connect_blocks(&nodes[3], final_cltv - HTLC_FAIL_BACK_BUFFER - nodes[3].best_block_info().1
+ - if fail_payment { 0 } else { 2 });
+ if fail_payment {
+ // We fail the HTLC on the A->B->D path first as it expires 4 blocks earlier. We go ahead
+ // and expire both immediately, though, by connecting another 4 blocks.
+ let reason = HTLCDestination::FailedPayment { payment_hash };
+ expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[3], [reason.clone()]);
+ connect_blocks(&nodes[3], 4);
+ expect_pending_htlcs_forwardable_and_htlc_handling_failed!(&nodes[3], [reason]);
+ pass_failed_payment_back(&nodes[0], &[&[&nodes[1], &nodes[3]], &[&nodes[2], &nodes[3]]], false, payment_hash);
+ } else {
+ nodes[1].node.force_close_broadcasting_latest_txn(&chan_bd, &nodes[3].node.get_our_node_id()).unwrap();
+ check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false);
+ check_closed_broadcast(&nodes[1], 1, true);
+ let bs_tx = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+ assert_eq!(bs_tx.len(), 1);
+
+ mine_transaction(&nodes[3], &bs_tx[0]);
+ check_added_monitors(&nodes[3], 1);
+ check_closed_broadcast(&nodes[3], 1, true);
+ check_closed_event(&nodes[3], 1, ClosureReason::CommitmentTxConfirmed, false);
+
+ nodes[3].node.claim_funds(payment_preimage);
+ check_added_monitors(&nodes[3], 2);
+ expect_payment_claimed!(nodes[3], payment_hash, 10_000_000);
+
+ let ds_tx = nodes[3].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
+ assert_eq!(ds_tx.len(), 1);
+ check_spends!(&ds_tx[0], &bs_tx[0]);
+
+ mine_transactions(&nodes[1], &[&bs_tx[0], &ds_tx[0]]);
+ check_added_monitors(&nodes[1], 1);
+ expect_payment_forwarded!(nodes[1], nodes[0], nodes[3], Some(1000), false, true);
+
+ let bs_claims = nodes[1].node.get_and_clear_pending_msg_events();
+ check_added_monitors(&nodes[1], 1);
+ assert_eq!(bs_claims.len(), 1);
+ if let MessageSendEvent::UpdateHTLCs { updates, .. } = &bs_claims[0] {
+ nodes[0].node.handle_update_fulfill_htlc(&nodes[1].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
+ commitment_signed_dance!(nodes[0], nodes[1], updates.commitment_signed, false, true);
+ } else { panic!(); }
+
+ expect_payment_sent!(nodes[0], payment_preimage);
+
+ let ds_claim_msgs = nodes[3].node.get_and_clear_pending_msg_events();
+ assert_eq!(ds_claim_msgs.len(), 1);
+ let cs_claim_msgs = if let MessageSendEvent::UpdateHTLCs { updates, .. } = &ds_claim_msgs[0] {
+ nodes[2].node.handle_update_fulfill_htlc(&nodes[3].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
+ let cs_claim_msgs = nodes[2].node.get_and_clear_pending_msg_events();
+ check_added_monitors(&nodes[2], 1);
+ commitment_signed_dance!(nodes[2], nodes[3], updates.commitment_signed, false, true);
+ expect_payment_forwarded!(nodes[2], nodes[0], nodes[3], Some(1000), false, false);
+ cs_claim_msgs
+ } else { panic!(); };
+
+ assert_eq!(cs_claim_msgs.len(), 1);
+ if let MessageSendEvent::UpdateHTLCs { updates, .. } = &cs_claim_msgs[0] {
+ nodes[0].node.handle_update_fulfill_htlc(&nodes[2].node.get_our_node_id(), &updates.update_fulfill_htlcs[0]);
+ commitment_signed_dance!(nodes[0], nodes[2], updates.commitment_signed, false, true);
+ } else { panic!(); }
+
+ expect_payment_path_successful!(nodes[0]);
+ }
+}
+
+#[test]
+fn claim_from_closed_chan() {
+ do_claim_from_closed_chan(true);
+ do_claim_from_closed_chan(false);
+}
projects / rust-lightning / commitdiff