Add a message field to ClosureReason::HolderForceClosed

In d17e759 we added the ability
for users to decide which message to send to peers when we
force-close a channel. Here we pipe that message back out through
the channel closure event via a new `message` field in
`ClosureReason::HolderForceClosed`.

This is nice to have but more importantly will be used in a coming
commit to simplify the internal interface to the force-closure
logic.

Author: TheBlueMatt

lightning-persister/src/fs_store.rs

@@ -592,23 +592,19 @@ mod tests {
 		let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+
+		let node_a_id = nodes[0].node.get_our_node_id();
+
 		let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
-		let error_message = "Channel force-closed";
+
+		let message = "Channel force-closed".to_owned();
 		nodes[1]
 			.node
-			.force_close_broadcasting_latest_txn(
-				&chan.2,
-				&nodes[0].node.get_our_node_id(),
-				error_message.to_string(),
-			)
+			.force_close_broadcasting_latest_txn(&chan.2, &node_a_id, message.clone())
 			.unwrap();
-		check_closed_event!(
-			nodes[1],
-			1,
-			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) },
-			[nodes[0].node.get_our_node_id()],
-			100000
-		);
+		let reason =
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
+		check_closed_event!(nodes[1], 1, reason, [node_a_id], 100000);
 		let mut added_monitors = nodes[1].chain_monitor.added_monitors.lock().unwrap();
 
 		// Set the store's directory to read-only, which should result in
@@ -640,23 +636,19 @@ mod tests {
 		let node_cfgs = create_node_cfgs(2, &chanmon_cfgs);
 		let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 		let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
+
+		let node_a_id = nodes[0].node.get_our_node_id();
+
 		let chan = create_announced_chan_between_nodes(&nodes, 0, 1);
-		let error_message = "Channel force-closed";
+
+		let message = "Channel force-closed".to_owned();
 		nodes[1]
 			.node
-			.force_close_broadcasting_latest_txn(
-				&chan.2,
-				&nodes[0].node.get_our_node_id(),
-				error_message.to_string(),
-			)
+			.force_close_broadcasting_latest_txn(&chan.2, &node_a_id, message.clone())
 			.unwrap();
-		check_closed_event!(
-			nodes[1],
-			1,
-			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) },
-			[nodes[0].node.get_our_node_id()],
-			100000
-		);
+		let reason =
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
+		check_closed_event!(nodes[1], 1, reason, [node_a_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();
 		let update_id = update_map.get(&added_monitors[0].1.channel_id()).unwrap();

lightning-persister/src/test_utils.rs

@@ -137,6 +137,8 @@ pub(crate) fn do_test_store<K: KVStore + Sync>(store_0: &K, store_1: &K) {
 	let node_chanmgrs = create_node_chanmgrs(2, &node_cfgs, &[None, None]);
 	let nodes = create_network(2, &node_cfgs, &node_chanmgrs);
 
+	let node_b_id = nodes[1].node.get_our_node_id();
+
 	// Check that the persisted channel data is empty before any channels are
 	// open.
 	let mut persisted_chan_data_0 =
@@ -178,22 +180,14 @@ pub(crate) fn do_test_store<K: KVStore + Sync>(store_0: &K, store_1: &K) {
 
 	// Force close because cooperative close doesn't result in any persisted
 	// updates.
-	let error_message = "Channel force-closed";
+	let message = "Channel force-closed".to_owned();
+	let chan_id = nodes[0].node.list_channels()[0].channel_id;
 	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(),
-		)
+		.force_close_broadcasting_latest_txn(&chan_id, &node_b_id, message.clone())
 		.unwrap();
-	check_closed_event!(
-		nodes[0],
-		1,
-		ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) },
-		[nodes[1].node.get_our_node_id()],
-		100000
-	);
+	let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
+	check_closed_event!(nodes[0], 1, reason, [node_b_id], 100000);
 	check_closed_broadcast!(nodes[0], true);
 	check_added_monitors!(nodes[0], 1);
 

lightning/src/chain/chainmonitor.rs

@@ -1458,12 +1458,13 @@ mod tests {
 
 		// Test that monitors with pending_claims are persisted on every block.
 		// Now, close channel_2 i.e. b/w node-0 and node-2 to create pending_claim in node[0].
+		let message = "Channel force-closed".to_owned();
 		nodes[0]
 			.node
-			.force_close_broadcasting_latest_txn(&channel_2, &node_c_id, "closed".to_string())
+			.force_close_broadcasting_latest_txn(&channel_2, &node_c_id, message.clone())
 			.unwrap();
 		let closure_reason =
-			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 		check_closed_event!(&nodes[0], 1, closure_reason, false, [node_c_id], 1000000);
 		check_closed_broadcast(&nodes[0], 1, true);
 		let close_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);

lightning/src/chain/channelmonitor.rs

@@ -3551,7 +3551,11 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
 		F::Target: FeeEstimator,
 		L::Target: Logger,
 	{
-		let (claimable_outpoints, _) = self.generate_claimable_outpoints_and_watch_outputs(ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) });
+		let reason = ClosureReason::HolderForceClosed {
+			broadcasted_latest_txn: Some(true),
+			message: "ChannelMonitor-initiated commitment transaction broadcast".to_owned(),
+		};
+		let (claimable_outpoints, _) = self.generate_claimable_outpoints_and_watch_outputs(reason);
 		let conf_target = self.closure_conf_target();
 		self.onchain_tx_handler.update_claims_view_from_requests(
 			claimable_outpoints, self.best_block.height, self.best_block.height, broadcaster,

lightning/src/events/mod.rs

@@ -318,9 +318,11 @@ pub enum ClosureReason {
 		/// [`UntrustedString`]: crate::util::string::UntrustedString
 		peer_msg: UntrustedString,
 	},
-	/// Closure generated from [`ChannelManager::force_close_channel`], called by the user.
+	/// Closure generated from [`ChannelManager::force_close_broadcasting_latest_txn`] or
+	/// [`ChannelManager::force_close_all_channels_broadcasting_latest_txn`], called by the user.
 	///
-	/// [`ChannelManager::force_close_channel`]: crate::ln::channelmanager::ChannelManager::force_close_channel.
+	/// [`ChannelManager::force_close_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_broadcasting_latest_txn
+	/// [`ChannelManager::force_close_all_channels_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_all_channels_broadcasting_latest_txn
 	HolderForceClosed {
 		/// Whether or not the latest transaction was broadcasted when the channel was force
 		/// closed.
@@ -335,6 +337,14 @@ pub enum ClosureReason {
 		/// [`ChannelManager::force_close_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_broadcasting_latest_txn.
 		/// [`ChannelManager::force_close_without_broadcasting_txn`]: crate::ln::channelmanager::ChannelManager::force_close_without_broadcasting_txn.
 		broadcasted_latest_txn: Option<bool>,
+		/// The error message provided to [`ChannelManager::force_close_broadcasting_latest_txn`] or
+		/// [`ChannelManager::force_close_all_channels_broadcasting_latest_txn`].
+		///
+		/// This will be the empty string for objects generated or written by LDK 0.1 and earlier.
+		///
+		/// [`ChannelManager::force_close_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_broadcasting_latest_txn
+		/// [`ChannelManager::force_close_all_channels_broadcasting_latest_txn`]: crate::ln::channelmanager::ChannelManager::force_close_all_channels_broadcasting_latest_txn
+		message: String,
 	},
 	/// The channel was closed after negotiating a cooperative close and we've now broadcasted
 	/// the cooperative close transaction. Note the shutdown may have been initiated by us.
@@ -419,12 +429,13 @@ impl core::fmt::Display for ClosureReason {
 			ClosureReason::CounterpartyForceClosed { peer_msg } => {
 				f.write_fmt(format_args!("counterparty force-closed with message: {}", peer_msg))
 			},
-			ClosureReason::HolderForceClosed { broadcasted_latest_txn } => {
-				f.write_str("user force-closed the channel")?;
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn, message } => {
+				f.write_str("user force-closed the channel with the message \"")?;
+				f.write_str(message)?;
 				if let Some(brodcasted) = broadcasted_latest_txn {
 					write!(
 						f,
-						" and {} the latest transaction",
+						"\" and {} the latest transaction",
 						if *brodcasted { "broadcasted" } else { "elected not to broadcast" }
 					)
 				} else {
@@ -482,7 +493,10 @@ impl core::fmt::Display for ClosureReason {
 impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
 	(0, CounterpartyForceClosed) => { (1, peer_msg, required) },
 	(1, FundingTimedOut) => {},
-	(2, HolderForceClosed) => { (1, broadcasted_latest_txn, option) },
+	(2, HolderForceClosed) => {
+		(1, broadcasted_latest_txn, option),
+		(3, message, (default_value, String::new())),
+	},
 	(6, CommitmentTxConfirmed) => {},
 	(4, LegacyCooperativeClosure) => {},
 	(8, ProcessingError) => { (1, err, required) },

lightning/src/ln/async_signer_tests.rs

@@ -1011,17 +1011,18 @@ 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";
 
 	if remote_commitment {
+		let message = "Channel force-closed".to_owned();
 		// Make the counterparty broadcast its latest commitment.
 		nodes[1]
 			.node
-			.force_close_broadcasting_latest_txn(&chan_id, &node_a_id, error_message.to_string())
+			.force_close_broadcasting_latest_txn(&chan_id, &node_a_id, message.clone())
 			.unwrap();
 		check_added_monitors(&nodes[1], 1);
 		check_closed_broadcast(&nodes[1], 1, true);
-		let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+		let reason =
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 		check_closed_event(&nodes[1], 1, reason, false, &[node_a_id], 100_000);
 	} else {
 		nodes[0].disable_channel_signer_op(&node_b_id, &chan_id, SignerOp::SignHolderCommitment);

lightning/src/ln/chanmon_update_fail_tests.rs

@@ -261,16 +261,19 @@ fn do_test_simple_monitor_temporary_update_fail(disconnect: bool) {
 	}
 
 	// ...and make sure we can force-close a frozen channel
-	let err_msg = "Channel force-closed".to_owned();
-	nodes[0].node.force_close_broadcasting_latest_txn(&channel_id, &node_b_id, err_msg).unwrap();
+	let message = "Channel force-closed".to_owned();
+	let reason = ClosureReason::HolderForceClosed {
+		broadcasted_latest_txn: Some(true),
+		message: message.clone(),
+	};
+	nodes[0].node.force_close_broadcasting_latest_txn(&channel_id, &node_b_id, message).unwrap();
 	check_added_monitors!(nodes[0], 1);
 	check_closed_broadcast!(nodes[0], true);
 
 	// TODO: Once we hit the chain with the failure transaction we should check that we get a
 	// PaymentPathFailed event
 
 	assert_eq!(nodes[0].node.list_channels().len(), 0);
-	let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
 	check_closed_event!(nodes[0], 1, reason, [node_b_id], 100000);
 }
 
@@ -3757,27 +3760,30 @@ fn do_test_durable_preimages_on_closed_channel(
 	let _ = get_revoke_commit_msgs!(nodes[1], node_c_id);
 
 	let mon_bc = get_monitor!(nodes[1], chan_id_bc).encode();
-	let err_msg = "Channel force-closed".to_owned();
 
 	if close_chans_before_reload {
 		if !close_only_a {
 			chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+			let message = "Channel force-closed".to_owned();
 			nodes[1]
 				.node
-				.force_close_broadcasting_latest_txn(&chan_id_bc, &node_c_id, err_msg.clone())
+				.force_close_broadcasting_latest_txn(&chan_id_bc, &node_c_id, message.clone())
 				.unwrap();
 			check_closed_broadcast(&nodes[1], 1, true);
-			let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+			let reason =
+				ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 			check_closed_event(&nodes[1], 1, reason, false, &[node_c_id], 100000);
 		}
 
 		chanmon_cfgs[1].persister.set_update_ret(ChannelMonitorUpdateStatus::InProgress);
+		let message = "Channel force-closed".to_owned();
 		nodes[1]
 			.node
-			.force_close_broadcasting_latest_txn(&chan_id_ab, &node_a_id, err_msg)
+			.force_close_broadcasting_latest_txn(&chan_id_ab, &node_a_id, message.clone())
 			.unwrap();
 		check_closed_broadcast(&nodes[1], 1, true);
-		let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+		let reason =
+			ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 		check_closed_event(&nodes[1], 1, reason, false, &[node_a_id], 100000);
 	}
 
@@ -3799,8 +3805,11 @@ fn do_test_durable_preimages_on_closed_channel(
 	}
 
 	let err_msg = "Channel force-closed".to_owned();
+	let reason = ClosureReason::HolderForceClosed {
+		broadcasted_latest_txn: Some(true),
+		message: err_msg.clone(),
+	};
 	nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &node_b_id, err_msg).unwrap();
-	let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
 	check_closed_event(&nodes[0], 1, reason, false, &[node_b_id], 100000);
 	let as_closing_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 	assert_eq!(as_closing_tx.len(), 1);
@@ -3964,10 +3973,13 @@ fn do_test_reload_mon_update_completion_actions(close_during_reload: bool) {
 	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).
+		let reason = ClosureReason::HolderForceClosed {
+			broadcasted_latest_txn: Some(true),
+			message: msg.clone(),
+		};
 		nodes[0].node.force_close_broadcasting_latest_txn(&chan_id_ab, &node_b_id, msg).unwrap();
 		check_added_monitors!(nodes[0], 1);
 		check_closed_broadcast!(nodes[0], true);
-		let reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
 		check_closed_event(&nodes[0], 1, reason, false, &[node_b_id], 100_000);
 		let as_closing_tx = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
 		mine_transaction_without_consistency_checks(&nodes[1], &as_closing_tx[0]);
@@ -4292,12 +4304,13 @@ fn test_claim_to_closed_channel_blocks_forwarded_preimage_removal() {
 	let (payment_preimage, payment_hash, ..) =
 		route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000);
 
+	let message = "Channel force-closed".to_owned();
 	nodes[0]
 		.node
-		.force_close_broadcasting_latest_txn(&chan_a.2, &node_b_id, String::new())
+		.force_close_broadcasting_latest_txn(&chan_a.2, &node_b_id, message.clone())
 		.unwrap();
 	check_added_monitors!(nodes[0], 1);
-	let a_reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+	let a_reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 	check_closed_event!(nodes[0], 1, a_reason, [node_b_id], 1000000);
 	check_closed_broadcast!(nodes[0], true);
 
@@ -4367,12 +4380,13 @@ fn test_claim_to_closed_channel_blocks_claimed_event() {
 
 	let (payment_preimage, payment_hash, ..) = route_payment(&nodes[0], &[&nodes[1]], 1_000_000);
 
+	let message = "Channel force-closed".to_owned();
 	nodes[0]
 		.node
-		.force_close_broadcasting_latest_txn(&chan_a.2, &node_b_id, String::new())
+		.force_close_broadcasting_latest_txn(&chan_a.2, &node_b_id, message.clone())
 		.unwrap();
 	check_added_monitors!(nodes[0], 1);
-	let a_reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true) };
+	let a_reason = ClosureReason::HolderForceClosed { broadcasted_latest_txn: Some(true), message };
 	check_closed_event!(nodes[0], 1, a_reason, [node_b_id], 1000000);
 	check_closed_broadcast!(nodes[0], true);