wip

Author: TheBlueMatt

lightning/Cargo.toml

@@ -23,6 +23,7 @@ _externalize_tests = ["inventory", "_test_utils"]
 # Allow signing of local transactions that may have been revoked or will be revoked, for functional testing (e.g. justice tx handling).
 # This is unsafe to use in production because it may result in the counterparty publishing taking our funds.
 unsafe_revoked_tx_signing = []
+backtrace = []
 
 std = []
 
@@ -46,7 +47,7 @@ hashbrown = { version = "0.13", default-features = false }
 possiblyrandom = { version = "0.2", path = "../possiblyrandom", default-features = false }
 
 regex = { version = "1.5.6", optional = true }
-backtrace = { version = "0.3", optional = true }
+backtrace = { version = "0.3"}
 
 libm = { version = "0.2", default-features = false }
 inventory = { version = "0.3", optional = true  }

lightning/src/ln/blinded_payment_tests.rs

@@ -1857,7 +1857,7 @@ fn test_combined_trampoline_onion_creation_vectors() {
 				short_channel_id: (572330 << 40) + (42 << 16) + 2821,
 				channel_features: ChannelFeatures::empty(),
 				fee_msat: 153_000,
-				cltv_expiry_delta: 0,
+				cltv_expiry_delta: 24 + 36,
 				maybe_announced_channel: false,
 			},
 		],
@@ -1952,7 +1952,7 @@ fn test_trampoline_inbound_payment_decoding() {
 				short_channel_id: (572330 << 40) + (42 << 16) + 2821,
 				channel_features: ChannelFeatures::empty(),
 				fee_msat: 150_153_000,
-				cltv_expiry_delta: 0,
+				cltv_expiry_delta: 24 + 36,
 				maybe_announced_channel: false,
 			},
 		],
@@ -2120,7 +2120,7 @@ fn test_trampoline_forward_payload_encoded_as_receive() {
 		blinded_path::utils::construct_blinded_hops(
 			&secp_ctx, path.into_iter(), &trampoline_session_priv,
 		)
-  };
+	};
 
 	let route = Route {
 		paths: vec![Path {
@@ -2143,7 +2143,7 @@ fn test_trampoline_forward_payload_encoded_as_receive() {
 					short_channel_id: bob_carol_scid,
 					channel_features: ChannelFeatures::empty(),
 					fee_msat: 0,
-					cltv_expiry_delta: 48,
+					cltv_expiry_delta: 24 + 39,
 					maybe_announced_channel: false,
 				}
 			],
@@ -2309,7 +2309,7 @@ fn do_test_trampoline_single_hop_receive(success: bool) {
 					short_channel_id: bob_carol_scid,
 					channel_features: ChannelFeatures::empty(),
 					fee_msat: 0,
-					cltv_expiry_delta: 48,
+					cltv_expiry_delta: 104 + 39,
 					maybe_announced_channel: false,
 				}
 			],
@@ -2797,7 +2797,7 @@ fn test_trampoline_forward_rejection() {
 					short_channel_id: bob_carol_scid,
 					channel_features: ChannelFeatures::empty(),
 					fee_msat: 0,
-					cltv_expiry_delta: 48,
+					cltv_expiry_delta: 24 + 24 + 39,
 					maybe_announced_channel: false,
 				}
 			],

lightning/src/ln/htlc_reserve_unit_tests.rs

@@ -1421,6 +1421,7 @@ pub fn test_update_add_htlc_bolt2_sender_cltv_expiry_too_high() {
 		.unwrap();
 	let (mut route, our_payment_hash, _, our_payment_secret) =
 		get_route_and_payment_hash!(nodes[0], nodes[1], payment_params, 100000000);
+	route.route_params.as_mut().unwrap().payment_params.max_total_cltv_expiry_delta = 500000001;
 	route.paths[0].hops.last_mut().unwrap().cltv_expiry_delta = 500000001;
 
 	let onion = RecipientOnionFields::secret_only(our_payment_secret, 100000000);

lightning/src/ln/onion_payment.rs

@@ -77,6 +77,7 @@ fn check_trampoline_payment_constraints(
 	trampoline_amount: u64,
 ) -> Result<(), InboundHTLCErr> {
 	if outer_hop_data.outgoing_cltv_value < trampoline_cltv_value {
+eprintln!("\n\n{} < {}\n", outer_hop_data.outgoing_cltv_value, trampoline_cltv_value);
 		return Err(InboundHTLCErr {
 			reason: LocalHTLCFailureReason::FinalIncorrectCLTVExpiry,
 			err_data: outer_hop_data.outgoing_cltv_value.to_be_bytes().to_vec(),

lightning/src/ln/onion_route_tests.rs

@@ -1918,7 +1918,7 @@ fn test_trampoline_onion_payload_assembly_values() {
 				short_channel_id: (572330 << 40) + (42 << 16) + 2821,
 				channel_features: ChannelFeatures::empty(),
 				fee_msat: 153_000,
-				cltv_expiry_delta: 0,
+				cltv_expiry_delta: 36 + 24, // Last hop should include the CLTV of the trampoline hops
 				maybe_announced_channel: false,
 			},
 		],
@@ -1974,7 +1974,7 @@ fn test_trampoline_onion_payload_assembly_values() {
 		SecretKey::from_slice(&<Vec<u8>>::from_hex(SECRET_HEX).unwrap()).unwrap().secret_bytes(),
 	);
 	let recipient_onion_fields = RecipientOnionFields::secret_only(payment_secret, amt_msat);
-	let (trampoline_payloads, outer_total_msat, outer_starting_htlc_offset) =
+	let (trampoline_payloads, outer_total_msat, outer_starting_htlc) =
 		onion_utils::build_trampoline_onion_payloads(
 			&path.blinded_tail.as_ref().unwrap(),
 			&recipient_onion_fields,
@@ -1984,7 +1984,7 @@ fn test_trampoline_onion_payload_assembly_values() {
 		.unwrap();
 	assert_eq!(trampoline_payloads.len(), 3);
 	assert_eq!(outer_total_msat, 150_153_000);
-	assert_eq!(outer_starting_htlc_offset, 800_060);
+	assert_eq!(outer_starting_htlc, 800_060);
 
 	let trampoline_carol_payload = &trampoline_payloads[0];
 	let trampoline_dave_payload = &trampoline_payloads[1];
@@ -2042,7 +2042,7 @@ fn test_trampoline_onion_payload_assembly_values() {
 	let (outer_payloads, total_msat, total_htlc_offset) = test_build_onion_payloads(
 		&path,
 		&recipient_onion_fields,
-		outer_starting_htlc_offset,
+		cur_height,
 		&None,
 		None,
 		Some(trampoline_packet),

lightning/src/ln/onion_utils.rs

@@ -158,6 +158,7 @@ impl<'a> PathHop for &'a RouteHop {
 	}
 
 	fn cltv_expiry_delta(&self) -> u32 {
+eprintln!("cltv for hop is {}", self.cltv_expiry_delta);
 		self.cltv_expiry_delta
 	}
 }
@@ -180,6 +181,7 @@ impl<'a> PathHop for &'a TrampolineHop {
 	}
 
 	fn cltv_expiry_delta(&self) -> u32 {
+eprintln!("trampoline hop cltv is {}", self.cltv_expiry_delta);
 		self.cltv_expiry_delta
 	}
 }
@@ -532,18 +534,16 @@ where
 {
 	let mut cur_value_msat = 0u64;
 	let mut cur_cltv = starting_htlc_offset;
+eprintln!("\n{:?}init'd cltv to {starting_htlc_offset}", ::backtrace::Backtrace::new());
 	let mut last_hop_id = None;
 
 	for (idx, hop) in hops.rev().enumerate() {
+eprintln!("\nloop idx {idx}. starting cltv {cur_cltv}");
 		// First hop gets special values so that it can check, on receipt, that everything is
 		// exactly as it should be (and the next hop isn't trying to probe to find out if we're
 		// the intended recipient).
 		let value_msat = if cur_value_msat == 0 { hop.fee_msat() } else { cur_value_msat };
-		let cltv = if cur_cltv == starting_htlc_offset {
-			hop.cltv_expiry_delta().saturating_add(starting_htlc_offset)
-		} else {
-			cur_cltv
-		};
+		let cltv = hop.cltv_expiry_delta().saturating_add(starting_htlc_offset);
 		if idx == 0 {
 			match blinded_tail.take() {
 				Some(BlindedTailDetails::DirectEntry {
@@ -553,6 +553,7 @@ where
 					excess_final_cltv_expiry_delta,
 					..
 				}) => {
+eprintln!("first hop is bp");
 					let mut blinding_point = Some(blinding_point);
 					let hops_len = hops.len();
 					for (i, blinded_hop) in hops.enumerate() {
@@ -586,18 +587,20 @@ where
 					trampoline_packet,
 					final_value_msat,
 				}) => {
+eprintln!("first hop is tramp");
 					cur_value_msat += final_value_msat;
 					callback(
 						PayloadCallbackAction::PushBack,
 						OP::new_trampoline_entry(
 							final_value_msat + hop.fee_msat(),
-							cur_cltv,
+							cltv,
 							&recipient_onion,
 							trampoline_packet,
 						)?,
 					);
 				},
 				None => {
+eprintln!("pushing regular first hop with cltv {cltv}");
 					callback(
 						PayloadCallbackAction::PushBack,
 						OP::new_receive(&recipient_onion, *keysend_preimage, value_msat, cltv)?,
@@ -610,14 +613,15 @@ where
 					err: "Next hop ID must be known for non-final hops".to_string(),
 				})?,
 				value_msat,
-				cltv,
+				cur_cltv,
 			);
 			callback(PayloadCallbackAction::PushFront, payload);
 		}
 		cur_value_msat += hop.fee_msat();
 		if cur_value_msat >= 21000000 * 100000000 * 1000 {
 			return Err(APIError::InvalidRoute { err: "Channel fees overflowed?".to_owned() });
 		}
+		eprintln!("cur cltv added {}", hop.cltv_expiry_delta());
 		cur_cltv = cur_cltv.saturating_add(hop.cltv_expiry_delta() as u32);
 		if cur_cltv >= 500000000 {
 			return Err(APIError::InvalidRoute { err: "Channel CLTV overflowed?".to_owned() });
@@ -2652,6 +2656,7 @@ pub(crate) fn create_payment_onion_internal<T: secp256k1::Signing>(
 		if !blinded_tail.trampoline_hops.is_empty() {
 			let trampoline_payloads;
 			let outer_total_msat;
+eprintln!("building trampoline onion.......");
 			(trampoline_payloads, outer_total_msat, outer_starting_htlc_offset) =
 				build_trampoline_onion_payloads(
 					&blinded_tail,
@@ -2683,14 +2688,16 @@ pub(crate) fn create_payment_onion_internal<T: secp256k1::Signing>(
 		}
 	}
 
+eprintln!("building real onion.......");
 	let (onion_payloads, htlc_msat, htlc_cltv) = build_onion_payloads(
 		&path,
 		outer_onion,
-		outer_starting_htlc_offset,
+		cur_block_height,
 		keysend_preimage,
 		invoice_request,
 		trampoline_packet_option,
 	)?;
+	debug_assert_eq!(htlc_cltv - cur_block_height, path.total_cltv_expiry_delta());
 
 	let onion_keys = construct_onion_keys(&secp_ctx, &path, session_priv);
 	let onion_packet = construct_onion_packet(onion_payloads, onion_keys, prng_seed, payment_hash)

lightning/src/routing/router.rs

@@ -642,6 +642,12 @@ impl Path {
 		}
 	}
 
+	/// Gets the total CLTV expiry delta which will be added to the current block height (plus some
+	/// extra headroom) when sending the HTLC
+	pub fn total_cltv_expiry_delta(&self) -> u32 {
+		self.hops.iter().map(|hop| hop.cltv_expiry_delta).sum()
+	}
+
 	/// True if this [`Path`] has at least one Trampoline hop.
 	pub fn has_trampoline_hops(&self) -> bool {
 		self.blinded_tail.as_ref().is_some_and(|bt| !bt.trampoline_hops.is_empty())
@@ -731,6 +737,17 @@ impl Route {
 					return Err(());
 				}
 
+				let total_cltv_delta = path.total_cltv_expiry_delta();
+				if total_cltv_delta > route_params.payment_params.max_total_cltv_expiry_delta {
+					let err = format!(
+						"Path had a total CLTV of {total_cltv_delta} which is greater than the maximum we're allowed {}",
+						route_params.payment_params.max_total_cltv_expiry_delta,
+					);
+					debug_assert!(false, "{}", err);
+					log_error!(logger, "{}", err);
+					return Err(());
+				}
+
 				if path.hops.len() > route_params.payment_params.max_path_length.into() {
 					let err = format!(
 						"Path had a length of {}, which is greater than the maximum we're allowed ({})",