Accept multi-hop route hints in get_route

Lightning invoices allow for zero or more multi-hop route hints. Update
get_route's interface to accept such hints, although only the last hop
from each is used for the time being.

Requires converting from lightning-invoice's RouteHint abstraction to
the wrapped RouteHintHop vector.

Author: jkczyz

fuzz/src/full_stack.rs

@@ -424,7 +424,7 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
 			},
 			4 => {
 				let value = slice_to_be24(get_slice!(3)) as u64;
-				let route = match get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &get_pubkey!(), None, None, &Vec::new(), value, 42, Arc::clone(&logger)) {
+				let route = match get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &get_pubkey!(), None, None, Vec::new(), value, 42, Arc::clone(&logger)) {
 					Ok(route) => route,
 					Err(_) => return,
 				};
@@ -441,7 +441,7 @@ pub fn do_test(data: &[u8], logger: &Arc<dyn Logger>) {
 			},
 			15 => {
 				let value = slice_to_be24(get_slice!(3)) as u64;
-				let mut route = match get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &get_pubkey!(), None, None, &Vec::new(), value, 42, Arc::clone(&logger)) {
+				let mut route = match get_route(&our_id, &net_graph_msg_handler.network_graph.read().unwrap(), &get_pubkey!(), None, None, Vec::new(), value, 42, Arc::clone(&logger)) {
 					Ok(route) => route,
 					Err(_) => return,
 				};

fuzz/src/router.rs

@@ -247,7 +247,7 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 				let last_hops = &last_hops_vec[..];
 				for target in node_pks.iter() {
 					let _ = get_route(&our_pubkey, &net_graph, target, None, first_hops,
-						&last_hops.iter().collect::<Vec<_>>(),
+						last_hops.iter().map(|hop| std::slice::from_ref(hop)).collect::<Vec<_>>(),
 						slice_to_be64(get_slice!(8)), slice_to_be32(get_slice!(4)), Arc::clone(&logger));
 				}
 			},

lightning-invoice/src/utils.rs

@@ -112,14 +112,9 @@ mod test {
 		assert_eq!(invoice.min_final_cltv_expiry(), MIN_FINAL_CLTV_EXPIRY as u64);
 		assert_eq!(invoice.description(), InvoiceDescription::Direct(&Description("test".to_string())));
 
-		let mut route_hints = invoice.routes().clone();
-		let mut last_hops = Vec::new();
-		for hint in route_hints.drain(..) {
-			last_hops.push(hint[hint.len() - 1].clone());
-		}
 		let amt_msat = invoice.amount_pico_btc().unwrap() / 10;
-
 		let first_hops = nodes[0].node.list_usable_channels();
+		let last_hops = invoice.routes().into_iter().map(|route| &(**route)[..]).collect();
 		let network_graph = nodes[0].net_graph_msg_handler.network_graph.read().unwrap();
 		let logger = test_utils::TestLogger::new();
 		let route = router::get_route(
@@ -128,7 +123,7 @@ mod test {
 			&invoice.recover_payee_pub_key(),
 			Some(invoice.features().unwrap().clone()),
 			Some(&first_hops),
-			&last_hops.iter().collect::<Vec<_>>(),
+			last_hops,
 			amt_msat,
 			invoice.min_final_cltv_expiry() as u32,
 			&logger,

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -4951,7 +4951,7 @@ pub mod bench {
 			($node_a: expr, $node_b: expr) => {
 				let usable_channels = $node_a.list_usable_channels();
 				let route = get_route(&$node_a.get_our_node_id(), &dummy_graph, &$node_b.get_our_node_id(), Some(InvoiceFeatures::known()),
-					Some(&usable_channels), &[], 10_000, TEST_FINAL_CLTV, &logger_a).unwrap();
+					Some(&usable_channels), Vec::new(), 10_000, TEST_FINAL_CLTV, &logger_a).unwrap();
 
 				let mut payment_preimage = PaymentPreimage([0; 32]);
 				payment_preimage.0[0..8].copy_from_slice(&payment_count.to_le_bytes());

lightning/src/ln/channelmanager.rs

@@ -945,7 +945,7 @@ macro_rules! get_route_and_payment_hash {
 		let net_graph_msg_handler = &$send_node.net_graph_msg_handler;
 		let route = get_route(&$send_node.node.get_our_node_id(),
 			&net_graph_msg_handler.network_graph.read().unwrap(),
-			&$recv_node.node.get_our_node_id(), None, None, &Vec::new(), $recv_value, TEST_FINAL_CLTV, $send_node.logger).unwrap();
+			&$recv_node.node.get_our_node_id(), None, None, Vec::new(), $recv_value, TEST_FINAL_CLTV, $send_node.logger).unwrap();
 		(route, payment_hash, payment_preimage, payment_secret)
 	}}
 }
@@ -1180,7 +1180,7 @@ pub const TEST_FINAL_CLTV: u32 = 70;
 pub fn route_payment<'a, 'b, 'c>(origin_node: &Node<'a, 'b, 'c>, expected_route: &[&Node<'a, 'b, 'c>], recv_value: u64) -> (PaymentPreimage, PaymentHash, PaymentSecret) {
 	let net_graph_msg_handler = &origin_node.net_graph_msg_handler;
 	let logger = test_utils::TestLogger::new();
-	let route = get_route(&origin_node.node.get_our_node_id(), &net_graph_msg_handler.network_graph.read().unwrap(), &expected_route.last().unwrap().node.get_our_node_id(), Some(InvoiceFeatures::known()), None, &Vec::new(), recv_value, TEST_FINAL_CLTV, &logger).unwrap();
+	let route = get_route(&origin_node.node.get_our_node_id(), &net_graph_msg_handler.network_graph.read().unwrap(), &expected_route.last().unwrap().node.get_our_node_id(), Some(InvoiceFeatures::known()), None, Vec::new(), recv_value, TEST_FINAL_CLTV, &logger).unwrap();
 	assert_eq!(route.paths.len(), 1);
 	assert_eq!(route.paths[0].len(), expected_route.len());
 	for (node, hop) in expected_route.iter().zip(route.paths[0].iter()) {
@@ -1193,7 +1193,7 @@ pub fn route_payment<'a, 'b, 'c>(origin_node: &Node<'a, 'b, 'c>, expected_route:
 pub fn route_over_limit<'a, 'b, 'c>(origin_node: &Node<'a, 'b, 'c>, expected_route: &[&Node<'a, 'b, 'c>], recv_value: u64)  {
 	let logger = test_utils::TestLogger::new();
 	let net_graph_msg_handler = &origin_node.net_graph_msg_handler;
-	let route = get_route(&origin_node.node.get_our_node_id(), &net_graph_msg_handler.network_graph.read().unwrap(), &expected_route.last().unwrap().node.get_our_node_id(), Some(InvoiceFeatures::known()), None, &Vec::new(), recv_value, TEST_FINAL_CLTV, &logger).unwrap();
+	let route = get_route(&origin_node.node.get_our_node_id(), &net_graph_msg_handler.network_graph.read().unwrap(), &expected_route.last().unwrap().node.get_our_node_id(), Some(InvoiceFeatures::known()), None, Vec::new(), recv_value, TEST_FINAL_CLTV, &logger).unwrap();
 	assert_eq!(route.paths.len(), 1);
 	assert_eq!(route.paths[0].len(), expected_route.len());
 	for (node, hop) in expected_route.iter().zip(route.paths[0].iter()) {