Filter on a per-channel basis.

Author: tnull

lightning/src/routing/router.rs

@@ -1810,18 +1810,24 @@ fn build_route_from_hops_internal<L: Deref>(
 	network_graph: &ReadOnlyNetworkGraph, final_value_msat: u64, final_cltv_expiry_delta: u32,
 	logger: L, random_seed_bytes: &[u8; 32]) -> Result<Route, LightningError> where L::Target: Logger {
 
-	let filter_by_nodeids = |_short_channel_id: u64, _send_amt_msat: u64, _capacity_msat: u64,
+	let filter_channels = |_short_channel_id: u64, _send_amt_msat: u64, _capacity_msat: u64,
 		source: &NodeId, target: &NodeId| {
-		let mut hop_iter = core::iter::once(NodeId::from_pubkey(&our_node_pubkey)).chain(hops.iter().map(|hop_pubkey| NodeId::from_pubkey(&hop_pubkey)));
-			if hop_iter.clone().find(|x| *x == *source).is_some()
-				&& hop_iter.find(|x| *x == *target).is_some() {
-					0
-				} else {
-					u64::max_value()
-				}
+
+		let node_ids_iter = hops.iter().map(|hop_pubkey| NodeId::from_pubkey(&hop_pubkey));
+		let mut hop_iter = core::iter::once(NodeId::from_pubkey(&our_node_pubkey))
+			.chain(node_ids_iter.clone())
+			.zip(node_ids_iter);
+
+		match hop_iter.find(|(cur_id, next_id)| {
+			(*cur_id == *source && *next_id == *target) ||
+			(*cur_id == *target && *next_id == *source) })
+		{
+			Some(_) => 0,
+			None => u64::max_value()
+		}
 	};
 
-	let scorer = DynamicPenaltyScorer::with_penalty_func(filter_by_nodeids);
+	let scorer = DynamicPenaltyScorer::with_penalty_func(filter_channels);
 
 	get_route(our_node_pubkey, payment_params, network_graph, None, final_value_msat,
 		final_cltv_expiry_delta, logger, &scorer, random_seed_bytes)