Send channel_update messages to direct peers on private channels

fuzz/src/chanmon_consistency.rs

@@ -571,7 +571,12 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 						events::MessageSendEvent::SendFundingLocked { .. } => continue,
 						events::MessageSendEvent::SendAnnouncementSignatures { .. } => continue,
 						events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => continue,
-						_ => panic!("Unhandled message event"),
+						events::MessageSendEvent::SendChannelUpdate { ref node_id, ref msg } => {
+							assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+							if Some(*node_id) == expect_drop_id { panic!("peer_disconnected should drop msgs bound for the disconnected peer"); }
+							*node_id == a_id
+						},
+						_ => panic!("Unhandled message event {:?}", event),
 					};
 					if push_a { ba_events.push(event); } else { bc_events.push(event); }
 				}
@@ -692,7 +697,16 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 							// Can be generated due to a payment forward being rejected due to a
 							// channel having previously failed a monitor update
 						},
-						_ => panic!("Unhandled message event"),
+						events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+							// When we reconnect we will resend a channel_update to make sure our
+							// counterparty has the latest parameters for receiving payments
+							// through us. We do, however, check that the message does not include
+							// the "disabled" bit, as we should never ever have a channel which is
+							// disabled when we send such an update (or it may indicate channel
+							// force-close which we should detect as an error).
+							assert_eq!(msg.contents.flags & 2, 0);
+						},
+						_ => panic!("Unhandled message event {:?}", event),
 					}
 					if $limit_events != ProcessMessages::AllMessages {
 						break;
@@ -722,6 +736,9 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 							events::MessageSendEvent::SendFundingLocked { .. } => {},
 							events::MessageSendEvent::SendAnnouncementSignatures { .. } => {},
 							events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {},
+							events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+								assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+							},
 							_ => panic!("Unhandled message event"),
 						}
 					}
@@ -737,6 +754,9 @@ pub fn do_test<Out: test_logger::Output>(data: &[u8], out: Out) {
 							events::MessageSendEvent::SendFundingLocked { .. } => {},
 							events::MessageSendEvent::SendAnnouncementSignatures { .. } => {},
 							events::MessageSendEvent::PaymentFailureNetworkUpdate { .. } => {},
+							events::MessageSendEvent::SendChannelUpdate { ref msg, .. } => {
+								assert_eq!(msg.contents.flags & 2, 0); // The disable bit must never be set!
+							},
 							_ => panic!("Unhandled message event"),
 						}
 					}

lightning-background-processor/src/lib.rs

@@ -443,9 +443,13 @@ mod tests {
 
 		// Confirm the funding transaction.
 		confirm_transaction(&mut nodes[0], &funding_tx);
+		let as_funding = get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id());
 		confirm_transaction(&mut nodes[1], &funding_tx);
-		nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id()));
-		nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &get_event_msg!(nodes[0], MessageSendEvent::SendFundingLocked, nodes[1].node.get_our_node_id()));
+		let bs_funding = get_event_msg!(nodes[1], MessageSendEvent::SendFundingLocked, nodes[0].node.get_our_node_id());
+		nodes[0].node.handle_funding_locked(&nodes[1].node.get_our_node_id(), &bs_funding);
+		let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
+		nodes[1].node.handle_funding_locked(&nodes[0].node.get_our_node_id(), &as_funding);
+		let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
 
 		assert!(bg_processor.stop().is_ok());
 

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -1158,7 +1158,10 @@ fn test_monitor_update_fail_reestablish() {
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
 
 	nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reestablish);
-	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+	assert_eq!(
+		get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id())
+			.contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected
+
 	nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
 	check_added_monitors!(nodes[1], 1);
 
@@ -1172,10 +1175,15 @@ fn test_monitor_update_fail_reestablish() {
 	assert!(bs_reestablish == get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id()));
 
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reestablish);
+	assert_eq!(
+		get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id())
+			.contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected
 
 	nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reestablish);
 	check_added_monitors!(nodes[1], 0);
-	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+	assert_eq!(
+		get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id())
+			.contents.flags & 2, 0); // The "disabled" bit should be unset as we just reconnected
 
 	*nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Ok(()));
 	let (outpoint, latest_update) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&chan_1.2).unwrap().clone();
@@ -1352,14 +1360,14 @@ fn claim_while_disconnected_monitor_update_fail() {
 	let bs_reconnect = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id());
 
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reconnect);
-	assert!(nodes[0].node.get_and_clear_pending_msg_events().is_empty());
+	let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
 
 	// Now deliver a's reestablish, freeing the claim from the holding cell, but fail the monitor
 	// update.
 	*nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Err(ChannelMonitorUpdateErr::TemporaryFailure));
 
 	nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reconnect);
-	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
+	let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
 	nodes[1].logger.assert_log("lightning::ln::channelmanager".to_string(), "Failed to update ChannelMonitor".to_string(), 1);
 	check_added_monitors!(nodes[1], 1);
 	assert!(nodes[1].node.get_and_clear_pending_msg_events().is_empty());
@@ -1492,7 +1500,9 @@ fn monitor_failed_no_reestablish_response() {
 	let bs_reconnect = get_event_msg!(nodes[1], MessageSendEvent::SendChannelReestablish, nodes[0].node.get_our_node_id());
 
 	nodes[1].node.handle_channel_reestablish(&nodes[0].node.get_our_node_id(), &as_reconnect);
+	let _bs_channel_update = get_event_msg!(nodes[1], MessageSendEvent::SendChannelUpdate, nodes[0].node.get_our_node_id());
 	nodes[0].node.handle_channel_reestablish(&nodes[1].node.get_our_node_id(), &bs_reconnect);
+	let _as_channel_update = get_event_msg!(nodes[0], MessageSendEvent::SendChannelUpdate, nodes[1].node.get_our_node_id());
 
 	*nodes[1].chain_monitor.update_ret.lock().unwrap() = Some(Ok(()));
 	let (outpoint, latest_update) = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap().get(&channel_id).unwrap().clone();