From a0d7cc7218f0ec54d099800d8ab6152cd87622f6 Mon Sep 17 00:00:00 2001 From: Valentine Wallace Date: Tue, 12 Sep 2023 14:57:59 -0400 Subject: [PATCH] Pathfinding: ignore blinded route hints where we are the intro node See tests, but the fuzzer found several panics from not fully ignoring these hints. We should support these route hints eventually, but it will involve some reworking of the Path/BlindedTail structs. --- lightning/src/routing/router.rs | 112 +++++++++++++++++++++++++++++++- 1 file changed, 111 insertions(+), 1 deletion(-) diff --git a/lightning/src/routing/router.rs b/lightning/src/routing/router.rs index 156e5e8e4fc..eb567d4dc62 100644 --- a/lightning/src/routing/router.rs +++ b/lightning/src/routing/router.rs @@ -2042,7 +2042,7 @@ where L::Target: Logger { // in the regular network graph. first_hop_targets.get(&intro_node_id).is_some() || network_nodes.get(&intro_node_id).is_some(); - if !have_intro_node_in_graph { continue } + if !have_intro_node_in_graph || our_node_id == intro_node_id { continue } let candidate = if hint.1.blinded_hops.len() == 1 { CandidateRouteHop::OneHopBlinded { hint, hint_idx } } else { CandidateRouteHop::Blinded { hint, hint_idx } }; @@ -7075,6 +7075,116 @@ mod tests { assert_eq!(route.get_total_fees(), blinded_payinfo.fee_base_msat as u64); assert_eq!(route.get_total_amount(), amt_msat); } + + #[test] + fn we_are_intro_node_candidate_hops() { + // This previously led to a panic in the router because we'd generate a Path with only a + // BlindedTail and 0 unblinded hops, due to the only candidate hops being blinded route hints + // where the origin node is the intro node. We now fully disallow considering candidate hops + // where the origin node is the intro node. + let (secp_ctx, network_graph, _, _, logger) = build_graph(); + let (_, our_id, _, nodes) = get_nodes(&secp_ctx); + 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 = 21_7020_5185_1423_0019; + + let blinded_path = BlindedPath { + introduction_node_id: our_id, + blinding_point: ln_test_utils::pubkey(42), + blinded_hops: vec![ + BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }, + BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() } + ], + }; + let blinded_payinfo = BlindedPayInfo { + fee_base_msat: 5052_9027, + fee_proportional_millionths: 5052_9027, + htlc_minimum_msat: 21_7020_5185_1423_0019, + htlc_maximum_msat: 1844_6744_0737_0955_1615, + cltv_expiry_delta: 0, + features: BlindedHopFeatures::empty(), + }; + let mut blinded_hints = vec![ + (blinded_payinfo.clone(), blinded_path.clone()), + (blinded_payinfo.clone(), blinded_path.clone()), + ]; + blinded_hints[1].1.introduction_node_id = nodes[6]; + + let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context(); + let payment_params = PaymentParameters::blinded(blinded_hints.clone()) + .with_bolt12_features(bolt12_features.clone()).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, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes + ) { + assert_eq!(err, "Failed to find a path to the given destination"); + } else { panic!() } + } + + #[test] + fn we_are_intro_node_bp_in_final_path_fee_calc() { + // This previously led to a debug panic in the router because we'd find an invalid Path with + // 0 unblinded hops and a blinded tail, leading to the generation of a final + // PaymentPathHop::fee_msat that included both the blinded path fees and the final value of + // the payment, when it was intended to only include the final value of the payment. + let (secp_ctx, network_graph, _, _, logger) = build_graph(); + let (_, our_id, _, nodes) = get_nodes(&secp_ctx); + 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 = 21_7020_5185_1423_0019; + + let blinded_path = BlindedPath { + introduction_node_id: our_id, + blinding_point: ln_test_utils::pubkey(42), + blinded_hops: vec![ + BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() }, + BlindedHop { blinded_node_id: ln_test_utils::pubkey(42 as u8), encrypted_payload: Vec::new() } + ], + }; + let blinded_payinfo = BlindedPayInfo { + fee_base_msat: 10_4425_1395, + fee_proportional_millionths: 1_6973_9011, + htlc_minimum_msat: 21_7301_9934_9094_0931, + htlc_maximum_msat: 1844_6744_0737_0955_1615, + cltv_expiry_delta: 0, + features: BlindedHopFeatures::empty(), + }; + let mut blinded_hints = vec![ + (blinded_payinfo.clone(), blinded_path.clone()), + (blinded_payinfo.clone(), blinded_path.clone()), + (blinded_payinfo.clone(), blinded_path.clone()), + ]; + blinded_hints[1].0.fee_base_msat = 5052_9027; + blinded_hints[1].0.fee_proportional_millionths = 5052_9027; + blinded_hints[1].0.htlc_minimum_msat = 21_7020_5185_1423_0019; + blinded_hints[1].0.htlc_maximum_msat = 1844_6744_0737_0955_1615; + + blinded_hints[2].1.introduction_node_id = nodes[6]; + + let bolt12_features: Bolt12InvoiceFeatures = channelmanager::provided_invoice_features(&config).to_context(); + let payment_params = PaymentParameters::blinded(blinded_hints.clone()) + .with_bolt12_features(bolt12_features.clone()).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, None, Arc::clone(&logger), &scorer, &(), &random_seed_bytes + ) { + assert_eq!(err, "Failed to find a path to the given destination"); + } else { panic!() } + } } #[cfg(all(any(test, ldk_bench), not(feature = "no-std")))]