.map_or(None, |inc| inc.checked_add(aggregate_next_hops_fee_msat));
aggregate_next_hops_fee_msat = if let Some(val) = hops_fee { val } else { break; };
- let hop_htlc_minimum_msat = candidate.htlc_minimum_msat();
- let hop_htlc_minimum_msat_inc = if let Some(val) = compute_fees(aggregate_next_hops_path_htlc_minimum_msat, hop.fees) { val } else { break; };
- let hops_path_htlc_minimum = aggregate_next_hops_path_htlc_minimum_msat
- .checked_add(hop_htlc_minimum_msat_inc);
- aggregate_next_hops_path_htlc_minimum_msat = if let Some(val) = hops_path_htlc_minimum { cmp::max(hop_htlc_minimum_msat, val) } else { break; };
+ // The next channel will need to relay this channel's min_htlc *plus* the fees taken by
+ // this route hint's source node to forward said min over this channel.
+ aggregate_next_hops_path_htlc_minimum_msat = {
+ let curr_htlc_min = cmp::max(
+ candidate.htlc_minimum_msat(), aggregate_next_hops_path_htlc_minimum_msat
+ );
+ let curr_htlc_min_fee = if let Some(val) = compute_fees(curr_htlc_min, hop.fees) { val } else { break };
+ if let Some(min) = curr_htlc_min.checked_add(curr_htlc_min_fee) { min } else { break }
+ };
if idx == route.0.len() - 1 {
// The last hop in this iterator is the first hop in
assert_eq!(err, "Failed to find a path to the given destination");
} else { panic!() }
}
+
+ #[test]
+ fn min_htlc_overpay_violates_max_htlc() {
+ // Test that if overpaying to meet a later hop's min_htlc and causes us to violate an earlier
+ // hop's max_htlc, we don't consider that candidate hop valid. Previously we would add this hop
+ // to `targets` and build an invalid path with it, and subsquently hit a debug panic asserting
+ // that the used liquidity for a hop was less than its available liquidity limit.
+ let secp_ctx = Secp256k1::new();
+ let logger = Arc::new(ln_test_utils::TestLogger::new());
+ let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
+ let scorer = ln_test_utils::TestScorer::new();
+ let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
+ let random_seed_bytes = keys_manager.get_secure_random_bytes();
+ let config = UserConfig::default();
+
+ // Values are taken from the fuzz input that uncovered this panic.
+ let amt_msat = 7_4009_8048;
+ let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
+ let first_hop_outbound_capacity = 2_7345_2000;
+ let first_hops = vec![get_channel_details(
+ Some(200), nodes[0], channelmanager::provided_init_features(&config),
+ first_hop_outbound_capacity
+ )];
+
+ let base_fee = 1_6778_3453;
+ let htlc_min = 2_5165_8240;
+ let payment_params = {
+ let route_hint = RouteHint(vec![RouteHintHop {
+ src_node_id: nodes[0],
+ short_channel_id: 42,
+ fees: RoutingFees {
+ base_msat: base_fee,
+ proportional_millionths: 0,
+ },
+ cltv_expiry_delta: 10,
+ htlc_minimum_msat: Some(htlc_min),
+ htlc_maximum_msat: None,
+ }]);
+
+ PaymentParameters::from_node_id(nodes[1], 42)
+ .with_route_hints(vec![route_hint]).unwrap()
+ .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
+ };
+
+ let netgraph = network_graph.read_only();
+ let route_params = RouteParameters::from_payment_params_and_value(
+ payment_params, amt_msat);
+ if let Err(LightningError { err, .. }) = get_route(
+ &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
+ Arc::clone(&logger), &scorer, &(), &random_seed_bytes
+ ) {
+ assert_eq!(err, "Failed to find a path to the given destination");
+ } else { panic!() }
+ }
+
+ #[test]
+ fn previously_used_liquidity_violates_max_htlc() {
+ // Test that if a candidate first_hop<>route_hint_src_node channel does not have enough
+ // contribution amount to cover the next hop's min_htlc plus fees, we will not consider that
+ // candidate. In this case, the candidate does not have enough due to a previous path taking up
+ // some of its liquidity. Previously we would construct an invalid path and hit a debug panic
+ // asserting that the used liquidity for a hop was less than its available liquidity limit.
+ let secp_ctx = Secp256k1::new();
+ let logger = Arc::new(ln_test_utils::TestLogger::new());
+ let network_graph = Arc::new(NetworkGraph::new(Network::Testnet, Arc::clone(&logger)));
+ let scorer = ln_test_utils::TestScorer::new();
+ let keys_manager = ln_test_utils::TestKeysInterface::new(&[0u8; 32], Network::Testnet);
+ let random_seed_bytes = keys_manager.get_secure_random_bytes();
+ let config = UserConfig::default();
+
+ // Values are taken from the fuzz input that uncovered this panic.
+ let amt_msat = 52_4288;
+ let (_, our_id, _, nodes) = get_nodes(&secp_ctx);
+ let first_hops = vec![get_channel_details(
+ Some(161), nodes[0], channelmanager::provided_init_features(&config), 486_4000
+ ), get_channel_details(
+ Some(122), nodes[0], channelmanager::provided_init_features(&config), 179_5000
+ )];
+
+ let base_fees = [0, 425_9840, 0, 0];
+ let htlc_mins = [1_4392, 19_7401, 1027, 6_5535];
+ let payment_params = {
+ let mut route_hints = Vec::new();
+ for (idx, (base_fee, htlc_min)) in base_fees.iter().zip(htlc_mins.iter()).enumerate() {
+ route_hints.push(RouteHint(vec![RouteHintHop {
+ src_node_id: nodes[0],
+ short_channel_id: 42 + idx as u64,
+ fees: RoutingFees {
+ base_msat: *base_fee,
+ proportional_millionths: 0,
+ },
+ cltv_expiry_delta: 10,
+ htlc_minimum_msat: Some(*htlc_min),
+ htlc_maximum_msat: Some(htlc_min * 100),
+ }]));
+ }
+ PaymentParameters::from_node_id(nodes[1], 42)
+ .with_route_hints(route_hints).unwrap()
+ .with_bolt11_features(channelmanager::provided_invoice_features(&config)).unwrap()
+ };
+
+ let netgraph = network_graph.read_only();
+ let route_params = RouteParameters::from_payment_params_and_value(
+ payment_params, amt_msat);
+
+ let route = get_route(
+ &our_id, &route_params, &netgraph, Some(&first_hops.iter().collect::<Vec<_>>()),
+ Arc::clone(&logger), &scorer, &(), &random_seed_bytes
+ ).unwrap();
+ assert_eq!(route.paths.len(), 1);
+ assert_eq!(route.get_total_amount(), amt_msat);
+ }
}
#[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]