Allowing user-specified error message during force close channel

In this commit i added additional parameter `error_message` to
`force_close_sending_error`. This parameter will allow users to
configure error message and send to peers during the force closing
of channel.I have also updated the tests for this updated function.

fuzz/src/full_stack.rs

@@ -731,9 +731,10 @@ pub fn do_test(mut data: &[u8], logger: &Arc<dyn Logger>) {
 			14 => {
 				let mut channels = channelmanager.list_channels();
 				let channel_id = get_slice!(1)[0] as usize;
+				let error_message = "Channel force-closed";
 				if channel_id >= channels.len() { return; }
 				channels.sort_by(|a, b| { a.channel_id.cmp(&b.channel_id) });
-				channelmanager.force_close_broadcasting_latest_txn(&channels[channel_id].channel_id, &channels[channel_id].counterparty.node_id).unwrap();
+				channelmanager.force_close_broadcasting_latest_txn(&channels[channel_id].channel_id, &channels[channel_id].counterparty.node_id, error_message.to_string()).unwrap();
 			},
 			// 15, 16, 17, 18 is above
 			19 => {

lightning-background-processor/src/lib.rs

@@ -1415,7 +1415,8 @@ mod tests {
 		}
 
 		// Force-close the channel.
-		nodes[0].node.force_close_broadcasting_latest_txn(&ChannelId::v1_from_funding_outpoint(OutPoint { txid: tx.txid(), index: 0 }), &nodes[1].node.get_our_node_id()).unwrap();
+		let error_message = "Channel force-closed";
+		nodes[0].node.force_close_broadcasting_latest_txn(&ChannelId::v1_from_funding_outpoint(OutPoint { txid: tx.txid(), index: 0 }), &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 
 		// Check that the force-close updates are persisted.
 		check_persisted_data!(nodes[0].node, filepath.clone());
@@ -1608,7 +1609,8 @@ mod tests {
 		let bg_processor = BackgroundProcessor::start(persister, event_handler, nodes[0].chain_monitor.clone(), nodes[0].node.clone(), nodes[0].no_gossip_sync(), nodes[0].peer_manager.clone(), nodes[0].logger.clone(), Some(nodes[0].scorer.clone()));
 
 		// Force close the channel and check that the SpendableOutputs event was handled.
-		nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
+		let error_message = "Channel force-closed";
+		nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 		let commitment_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().pop().unwrap();
 		confirm_transaction_depth(&mut nodes[0], &commitment_tx, BREAKDOWN_TIMEOUT as u32);
 

lightning-persister/src/fs_store.rs

@@ -446,7 +446,8 @@ mod tests {
 		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 		let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
-		nodes[1].node.force_close_broadcasting_latest_txn(&chan.2, &nodes[0].node.get_our_node_id()).unwrap();
+		let error_message = "Channel force-closed";
+		nodes[1].node.force_close_broadcasting_latest_txn(&chan.2, &nodes[0].node.get_our_node_id(), error_message.to_string()).unwrap();
 		check_closed_event!(nodes[1], 1, ClosureReason::HolderForceClosed, [nodes[0].node.get_our_node_id()], 100000);
 		let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 		let update_map = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap();
@@ -485,7 +486,8 @@ mod tests {
 		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 		let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
-		nodes[1].node.force_close_broadcasting_latest_txn(&chan.2, &nodes[0].node.get_our_node_id()).unwrap();
+		let error_message = "Channel force-closed";
+		nodes[1].node.force_close_broadcasting_latest_txn(&chan.2, &nodes[0].node.get_our_node_id(), error_message.to_string()).unwrap();
 		check_closed_event!(nodes[1], 1, ClosureReason::HolderForceClosed, [nodes[0].node.get_our_node_id()], 100000);
 		let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 		let update_map = nodes[1].chain_monitor.latest_monitor_update_id.lock().unwrap();

lightning-persister/src/test_utils.rs

@@ -104,7 +104,8 @@ pub(crate) fn do_test_store<K: KVStore>(store_0: &K, store_1: &K) {
 
 	// Force close because cooperative close doesn't result in any persisted
 	// updates.
-	nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id()).unwrap();
+	let error_message = "Channel force-closed";
+	nodes[0].node.force_close_broadcasting_latest_txn(&nodes[0].node.list_channels()[0].channel_id, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 	check_closed_event!(nodes[0], 1, ClosureReason::HolderForceClosed, [nodes[1].node.get_our_node_id()], 100000);
 	check_closed_broadcast!(nodes[0], true);
 	check_added_monitors!(nodes[0], 1);

lightning/src/ln/async_signer_tests.rs

@@ -363,12 +363,13 @@ fn do_test_async_holder_signatures(anchors: bool, remote_commitment: bool) {
 	// Route an HTLC and set the signer as unavailable.
 	let (_, _, chan_id, funding_tx) = create_announced_chan_between_nodes(&nodes, 0, 1);
 	route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
+	let error_message = "Channel force-closed";
 
 	nodes[0].set_channel_signer_available(&nodes[1].node.get_our_node_id(), &chan_id, false);
 
 	if remote_commitment {
 		// Make the counterparty broadcast its latest commitment.
-		nodes[1].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[0].node.get_our_node_id()).unwrap();
+		nodes[1].node.force_close_broadcasting_latest_txn(&chan_id, &nodes[0].node.get_our_node_id(), error_message.to_string()).unwrap();
 		check_added_monitors(&nodes[1], 1);
 		check_closed_broadcast(&nodes[1], 1, true);
 		check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[0].node.get_our_node_id()], 100_000);

lightning/src/ln/blinded_payment_tests.rs

@@ -457,6 +457,7 @@ fn do_forward_fail_in_process_pending_htlc_fwds(check: ProcessPendingHTLCsCheck,
 		(chan.0.contents, chan.2)
 	};
 
+	let error_message = "Channel force-closed";
 	let amt_msat = 5000;
 	let (_, payment_hash, payment_secret) = get_payment_preimage_hash(&nodes[2], Some(amt_msat), None);
 	let route_params = get_blinded_route_parameters(amt_msat, payment_secret, 1, 1_0000_0000,
@@ -489,7 +490,7 @@ fn do_forward_fail_in_process_pending_htlc_fwds(check: ProcessPendingHTLCsCheck,
 				ProcessPendingHTLCsCheck::FwdChannelClosed => {
 					// Force close the next-hop channel so when we go to forward in process_pending_htlc_forwards,
 					// the intro node will error backwards.
-					$curr_node.node.force_close_broadcasting_latest_txn(&$failed_chan_id, &$next_node.node.get_our_node_id()).unwrap();
+					$curr_node.node.force_close_broadcasting_latest_txn(&$failed_chan_id, &$next_node.node.get_our_node_id(), error_message.to_string()).unwrap();
 					let events = $curr_node.node.get_and_clear_pending_events();
 					match events[0] {
 						crate::events::Event::PendingHTLCsForwardable { .. } => {},

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -206,7 +206,8 @@ fn do_test_simple_monitor_temporary_update_fail(disconnect: bool) {
 	}
 
 	// ...and make sure we can force-close a frozen channel
-	nodes[0].node.force_close_broadcasting_latest_txn(&channel_id, &nodes[1].node.get_our_node_id()).unwrap();
+	let error_message = "Channel force-closed";
+	nodes[0].node.force_close_broadcasting_latest_txn(&channel_id, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 	check_added_monitors!(nodes[0], 1);
 	check_closed_broadcast!(nodes[0], true);
 
@@ -3221,17 +3222,18 @@ fn do_test_durable_preimages_on_closed_channel(close_chans_before_reload: bool,
 	let _ = get_revoke_commit_msgs!(nodes[1], nodes[2].node.get_our_node_id());
 
 	let mon_bc = get_monitor!(nodes[1], chan_id_bc).encode();
+	let error_message = "Channel force-closed";
 
 	if close_chans_before_reload {
 		if !close_only_a {
 			chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
-			nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_bc, &nodes[2].node.get_our_node_id()).unwrap();
+			nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_bc, &nodes[2].node.get_our_node_id(), error_message.to_string()).unwrap();
 			check_closed_broadcast(&nodes[1], 1, true);
 			check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[2].node.get_our_node_id()], 100000);
 		}
 
 		chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
-		nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[0].node.get_our_node_id()).unwrap();
+		nodes[1].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[0].node.get_our_node_id(), error_message.to_string()).unwrap();
 		check_closed_broadcast(&nodes[1], 1, true);
 		check_closed_event(&nodes[1], 1, ClosureReason::HolderForceClosed, false, &[nodes[0].node.get_our_node_id()], 100000);
 	}
@@ -3252,8 +3254,9 @@ fn do_test_durable_preimages_on_closed_channel(close_chans_before_reload: bool,
 			assert_eq!(bs_close_txn.len(), 3);
 		}
 	}
+	let error_message = "Channel force-closed";
 
-	nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id()).unwrap();
+	nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 	check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100000);
 	let as_closing_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 	assert_eq!(as_closing_tx.len(), 1);
@@ -3390,10 +3393,11 @@ fn do_test_reload_mon_update_completion_actions(close_during_reload: bool) {
 	let manager_b = nodes[1].node.encode();
 	reload_node!(nodes[1], &manager_b, &[&mon_ab, &mon_bc], persister, new_chain_monitor, nodes_1_deserialized);
 
+	let error_message = "Channel force-closed";
 	if close_during_reload {
 		// Test that we still free the B<->C channel if the A<->B channel closed while we reloaded
 		// (as learned about during the on-reload block connection).
-		nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id()).unwrap();
+		nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &nodes[1].node.get_our_node_id(), error_message.to_string()).unwrap();
 		check_added_monitors!(nodes[0], 1);
 		check_closed_broadcast!(nodes[0], true);
 		check_closed_event(&nodes[0], 1, ClosureReason::HolderForceClosed, false, &[nodes[1].node.get_our_node_id()], 100_000);