Add trampoline_hops field to Path

To specify Trampoline hops in Path instances, we need to introduce a
third field to the struct, which is a vec of TrampolineHops defined in
the previous commit.

Author: arik-so

fuzz/src/chanmon_consistency.rs

@@ -520,6 +520,7 @@ fn send_payment(
 				cltv_expiry_delta: 200,
 				maybe_announced_channel: true,
 			}],
+			trampoline_hops: vec![],
 			blinded_tail: None,
 		}],
 		route_params: Some(route_params.clone()),
@@ -604,6 +605,7 @@ fn send_hop_payment(
 					maybe_announced_channel: true,
 				},
 			],
+			trampoline_hops: vec![],
 			blinded_tail: None,
 		}],
 		route_params: Some(route_params.clone()),

lightning-background-processor/src/lib.rs

@@ -2540,7 +2540,7 @@ mod tests {
 				fee_msat: 0,
 				cltv_expiry_delta: MIN_CLTV_EXPIRY_DELTA as u32,
 				maybe_announced_channel: true,
-			}], blinded_tail: None };
+			}], trampoline_hops: vec![], blinded_tail: None };
 
 			$nodes[0].scorer.write_lock().expect(TestResult::PaymentFailure { path: path.clone(), short_channel_id: scored_scid });
 			$nodes[0].node.push_pending_event(Event::PaymentPathFailed {

lightning/src/events/mod.rs

@@ -30,7 +30,7 @@ use crate::types::payment::{PaymentPreimage, PaymentHash, PaymentSecret};
 use crate::offers::invoice::Bolt12Invoice;
 use crate::onion_message::messenger::Responder;
 use crate::routing::gossip::NetworkUpdate;
-use crate::routing::router::{BlindedTail, Path, RouteHop, RouteParameters};
+use crate::routing::router::{BlindedTail, Path, RouteHop, RouteParameters, TrampolineHop};
 use crate::sign::SpendableOutputDescriptor;
 use crate::util::errors::APIError;
 use crate::util::ser::{BigSize, FixedLengthReader, Writeable, Writer, MaybeReadable, Readable, RequiredWrapper, UpgradableRequired, WithoutLength};
@@ -1190,12 +1190,12 @@ pub enum Event {
 		/// events generated or serialized by versions prior to 0.0.122.
 		next_user_channel_id: Option<u128>,
 		/// The node id of the previous node.
-		/// 
+		///
 		/// This is only `None` for HTLCs received prior to 0.1 or for events serialized by
 		/// versions prior to 0.1
 		prev_node_id: Option<PublicKey>,
 		/// The node id of the next node.
-		/// 
+		///
 		/// This is only `None` for HTLCs received prior to 0.1 or for events serialized by
 		/// versions prior to 0.1
 		next_node_id: Option<PublicKey>,
@@ -1574,6 +1574,7 @@ impl Writeable for Event {
 					(2, payment_failed_permanently, required),
 					(3, false, required), // all_paths_failed in LDK versions prior to 0.0.114
 					(4, path.blinded_tail, option),
+					(6, path.trampoline_hops, optional_vec),
 					(5, path.hops, required_vec),
 					(7, short_channel_id, option),
 					(9, None::<RouteParameters>, option), // retry in LDK versions prior to 0.0.115
@@ -1665,6 +1666,7 @@ impl Writeable for Event {
 					(2, payment_hash, option),
 					(4, path.hops, required_vec),
 					(6, path.blinded_tail, option),
+					(8, path.trampoline_hops, optional_vec),
 				})
 			},
 			&Event::PaymentFailed { ref payment_id, ref payment_hash, ref reason } => {
@@ -1729,6 +1731,7 @@ impl Writeable for Event {
 					(2, payment_hash, required),
 					(4, path.hops, required_vec),
 					(6, path.blinded_tail, option),
+					(8, path.trampoline_hops, optional_vec),
 				})
 			},
 			&Event::ProbeFailed { ref payment_id, ref payment_hash, ref path, ref short_channel_id } => {
@@ -1739,6 +1742,7 @@ impl Writeable for Event {
 					(4, path.hops, required_vec),
 					(6, short_channel_id, option),
 					(8, path.blinded_tail, option),
+					(10, path.trampoline_hops, optional_vec)
 				})
 			},
 			&Event::HTLCHandlingFailed { ref prev_channel_id, ref failed_next_destination } => {
@@ -1915,6 +1919,7 @@ impl MaybeReadable for Event {
 					let mut network_update = None;
 					let mut blinded_tail: Option<BlindedTail> = None;
 					let mut path: Option<Vec<RouteHop>> = Some(vec![]);
+					let mut trampoline_path: Option<Vec<TrampolineHop>> = Some(vec![]);
 					let mut short_channel_id = None;
 					let mut payment_id = None;
 					let mut failure_opt = None;
@@ -1923,6 +1928,7 @@ impl MaybeReadable for Event {
 						(1, network_update, upgradable_option),
 						(2, payment_failed_permanently, required),
 						(4, blinded_tail, option),
+						(6, trampoline_path, optional_vec),
 						// Added as a part of LDK 0.0.101 and always filled in since.
 						// Defaults to an empty Vec, though likely should have been `Option`al.
 						(5, path, optional_vec),
@@ -1936,7 +1942,7 @@ impl MaybeReadable for Event {
 						payment_hash,
 						payment_failed_permanently,
 						failure,
-						path: Path { hops: path.unwrap(), blinded_tail },
+						path: Path { hops: path.unwrap(), trampoline_hops: trampoline_path.unwrap_or(vec![]), blinded_tail },
 						short_channel_id,
 						#[cfg(test)]
 						error_code,
@@ -2077,11 +2083,12 @@ impl MaybeReadable for Event {
 						(2, payment_hash, option),
 						(4, path, required_vec),
 						(6, blinded_tail, option),
+						(8, trampoline_path, optional_vec),
 					});
 					Ok(Some(Event::PaymentPathSuccessful {
 						payment_id: payment_id.0.unwrap(),
 						payment_hash,
-						path: Path { hops: path, blinded_tail },
+						path: Path { hops: path, trampoline_hops: trampoline_path.unwrap_or(vec![]), blinded_tail },
 					}))
 				};
 				f()
@@ -2157,11 +2164,12 @@ impl MaybeReadable for Event {
 						(2, payment_hash, required),
 						(4, path, required_vec),
 						(6, blinded_tail, option),
+						(8, trampoline_path, optional_vec)
 					});
 					Ok(Some(Event::ProbeSuccessful {
 						payment_id: payment_id.0.unwrap(),
 						payment_hash: payment_hash.0.unwrap(),
-						path: Path { hops: path, blinded_tail },
+						path: Path { hops: path, trampoline_hops: trampoline_path.unwrap_or(vec![]), blinded_tail },
 					}))
 				};
 				f()
@@ -2174,11 +2182,12 @@ impl MaybeReadable for Event {
 						(4, path, required_vec),
 						(6, short_channel_id, option),
 						(8, blinded_tail, option),
+						(10, trampoline_path, optional_vec)
 					});
 					Ok(Some(Event::ProbeFailed {
 						payment_id: payment_id.0.unwrap(),
 						payment_hash: payment_hash.0.unwrap(),
-						path: Path { hops: path, blinded_tail },
+						path: Path { hops: path, trampoline_hops: trampoline_path.unwrap_or(vec![]), blinded_tail },
 						short_channel_id,
 					}))
 				};

lightning/src/ln/blinded_payment_tests.rs

@@ -1504,6 +1504,7 @@ fn route_blinding_spec_test_vector() {
 			cltv_expiry_delta: 42,
 			maybe_announced_channel: false,
 		}],
+		trampoline_hops: vec![],
 		blinded_tail: Some(BlindedTail {
 			hops: blinded_hops,
 			blinding_point: bob_blinding_point,

lightning/src/ln/channel.rs

@@ -10666,7 +10666,7 @@ mod tests {
 			cltv_expiry: 200000000,
 			state: OutboundHTLCState::Committed,
 			source: HTLCSource::OutboundRoute {
-				path: Path { hops: Vec::new(), blinded_tail: None },
+				path: Path { hops: Vec::new(), trampoline_hops: vec![], blinded_tail: None },
 				session_priv: SecretKey::from_slice(&<Vec<u8>>::from_hex("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
 				first_hop_htlc_msat: 548,
 				payment_id: PaymentId([42; 32]),
@@ -11042,6 +11042,7 @@ mod tests {
 					node_features: NodeFeatures::empty(), short_channel_id: 0, fee_msat: 0,
 					cltv_expiry_delta: 0, maybe_announced_channel: false,
 				}],
+				trampoline_hops: vec![],
 				blinded_tail: None
 			},
 			session_priv: test_utils::privkey(42),

lightning/src/ln/channelmanager.rs

@@ -689,7 +689,7 @@ impl HTLCSource {
 	pub fn dummy() -> Self {
 		assert!(cfg!(not(feature = "grind_signatures")));
 		HTLCSource::OutboundRoute {
-			path: Path { hops: Vec::new(), blinded_tail: None },
+			path: Path { hops: Vec::new(), trampoline_hops: Vec::new(), blinded_tail: None },
 			session_priv: SecretKey::from_slice(&[1; 32]).unwrap(),
 			first_hop_htlc_msat: 0,
 			payment_id: PaymentId([2; 32]),
@@ -12618,7 +12618,7 @@ impl Readable for HTLCSource {
 					// instead.
 					payment_id = Some(PaymentId(*session_priv.0.unwrap().as_ref()));
 				}
-				let path = Path { hops: path_hops, blinded_tail };
+				let path = Path { hops: path_hops, trampoline_hops: vec![], blinded_tail };
 				if path.hops.len() == 0 {
 					return Err(DecodeError::InvalidValue);
 				}

lightning/src/ln/functional_tests.rs

@@ -1088,7 +1088,7 @@ fn fake_network_test() {
 	).with_bolt11_features(nodes[1].node.bolt11_invoice_features()).unwrap();
 	let route_params = RouteParameters::from_payment_params_and_value(payment_params, 1000000);
 	let payment_preimage_1 = send_along_route(&nodes[1],
-		Route { paths: vec![Path { hops, blinded_tail: None }], route_params: Some(route_params.clone()) },
+		Route { paths: vec![Path { hops, trampoline_hops: vec![], blinded_tail: None }], route_params: Some(route_params.clone()) },
 			&vec!(&nodes[2], &nodes[3], &nodes[1])[..], 1000000).0;
 
 	let mut hops = Vec::with_capacity(3);
@@ -1122,7 +1122,7 @@ fn fake_network_test() {
 	hops[1].fee_msat = chan_2.1.contents.fee_base_msat as u64 + chan_2.1.contents.fee_proportional_millionths as u64 * hops[2].fee_msat as u64 / 1000000;
 	hops[0].fee_msat = chan_3.1.contents.fee_base_msat as u64 + chan_3.1.contents.fee_proportional_millionths as u64 * hops[1].fee_msat as u64 / 1000000;
 	let payment_hash_2 = send_along_route(&nodes[1],
-		Route { paths: vec![Path { hops, blinded_tail: None }], route_params: Some(route_params) },
+		Route { paths: vec![Path { hops, trampoline_hops: vec![], blinded_tail: None }], route_params: Some(route_params) },
 			&vec!(&nodes[3], &nodes[2], &nodes[1])[..], 1000000).1;
 
 	// Claim the rebalances...

lightning/src/ln/onion_payment.rs

@@ -534,7 +534,7 @@ mod tests {
 		// Ensure the onion will not fit all the payloads by adding a large custom TLV.
 		recipient_onion.custom_tlvs.push((13377331, vec![0; 1156]));
 
-		let path = Path { hops, blinded_tail: None, };
+		let path = Path { hops, trampoline_hops: vec![], blinded_tail: None, };
 		let onion_keys = super::onion_utils::construct_onion_keys(&secp_ctx, &path, &session_priv).unwrap();
 		let (onion_payloads, ..) = super::onion_utils::build_onion_payloads(
 			&path, total_amt_msat, &recipient_onion, cur_height + 1, &Some(keysend_preimage), None
@@ -560,6 +560,7 @@ mod tests {
 
 		let path = Path {
 			hops: hops,
+			trampoline_hops: vec![],
 			blinded_tail: None,
 		};
 

lightning/src/ln/onion_utils.rs

@@ -1350,7 +1350,7 @@ mod tests {
 						channel_features: ChannelFeatures::empty(), node_features: NodeFeatures::empty(),
 						short_channel_id: 0, fee_msat: 0, cltv_expiry_delta: 0, maybe_announced_channel: true, // We fill in the payloads manually instead of generating them from RouteHops.
 					},
-			], blinded_tail: None }],
+			], trampoline_hops: vec![], blinded_tail: None }],
 			route_params: None,
 		};
 

lightning/src/ln/outbound_payment.rs

@@ -2582,7 +2582,7 @@ mod tests {
 				fee_msat: 0,
 				cltv_expiry_delta: 0,
 				maybe_announced_channel: true,
-			}], blinded_tail: None }],
+			}], trampoline_hops: vec![], blinded_tail: None }],
 			route_params: Some(route_params.clone()),
 		};
 		router.expect_find_route(route_params.clone(), Ok(route.clone()));
@@ -2938,6 +2938,7 @@ mod tests {
 								maybe_announced_channel: true,
 							}
 						],
+						trampoline_hops: vec![],
 						blinded_tail: None,
 					}
 				],