From 5663ebf8d278e171ca5a871b047387a664a13ee8 Mon Sep 17 00:00:00 2001 From: Valentine Wallace Date: Wed, 20 Dec 2023 14:04:04 -0500 Subject: [PATCH] Fix sender double-including shadow offset in outgoing CLTV expiry. The excess delta is included in the final RouteHop::cltv_expiry_delta, so by adding it explicitly to cur_cltv we were erroneously including it twice in the total cltv expiry. This could've add up to an extra MAX_SHADOW_CLTV_DELTA_OFFSET (432) blocks to the total cltv expiry. --- lightning/src/ln/blinded_payment_tests.rs | 2 ++ lightning/src/ln/onion_utils.rs | 3 +-- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/lightning/src/ln/blinded_payment_tests.rs b/lightning/src/ln/blinded_payment_tests.rs index b2094af1d6e..a3126b3b537 100644 --- a/lightning/src/ln/blinded_payment_tests.rs +++ b/lightning/src/ln/blinded_payment_tests.rs @@ -572,6 +572,7 @@ fn do_multi_hop_receiver_fail(check: ReceiveCheckFail) { let route = if check == ReceiveCheckFail::ProcessPendingHTLCsCheck { let mut route = get_route(&nodes[0], &route_params).unwrap(); // Set the final CLTV expiry too low to trigger the failure in process_pending_htlc_forwards. + route.paths[0].hops.last_mut().map(|h| h.cltv_expiry_delta += excess_final_cltv_delta_opt.unwrap() as u32); route.paths[0].blinded_tail.as_mut().map(|bt| bt.excess_final_cltv_expiry_delta = excess_final_cltv_delta_opt.unwrap() as u32); route } else if check == ReceiveCheckFail::PaymentConstraints { @@ -680,6 +681,7 @@ fn do_multi_hop_receiver_fail(check: ReceiveCheckFail) { commitment_signed_dance!(nodes[2], nodes[1], (), false, true, false, false); }, ReceiveCheckFail::ProcessPendingHTLCsCheck => { + assert_eq!(payment_event_1_2.msgs[0].cltv_expiry, nodes[0].best_block_info().1 + 1 + excess_final_cltv_delta_opt.unwrap() as u32); nodes[2].node.handle_update_add_htlc(&nodes[1].node.get_our_node_id(), &payment_event_1_2.msgs[0]); check_added_monitors!(nodes[2], 0); do_commitment_signed_dance(&nodes[2], &nodes[1], &payment_event_1_2.commitment_msg, true, true); diff --git a/lightning/src/ln/onion_utils.rs b/lightning/src/ln/onion_utils.rs index d858ceb88ef..95196c6a12f 100644 --- a/lightning/src/ln/onion_utils.rs +++ b/lightning/src/ln/onion_utils.rs @@ -188,11 +188,10 @@ pub(super) fn build_onion_payloads(path: &Path, total_msat: u64, mut recipient_o for (i, blinded_hop) in hops.iter().enumerate() { if i == hops.len() - 1 { cur_value_msat += final_value_msat; - cur_cltv += excess_final_cltv_expiry_delta; res.push(msgs::OutboundOnionPayload::BlindedReceive { amt_msat: *final_value_msat, total_msat, - outgoing_cltv_value: cur_cltv, + outgoing_cltv_value: cur_cltv + excess_final_cltv_expiry_delta, encrypted_tlvs: blinded_hop.encrypted_payload.clone(), intro_node_blinding_point: blinding_point.take(), });