Merge pull request #78 from MaxFangX/fix-chanman-race-panic

Fix channel manager race panic

Author: jkczyz

src/main.rs

@@ -17,7 +17,7 @@ use lightning::chain;
 use lightning::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator};
 use lightning::chain::keysinterface::{InMemorySigner, KeysInterface, KeysManager, Recipient};
 use lightning::chain::{chainmonitor, ChannelMonitorUpdateStatus};
-use lightning::chain::{BestBlock, Filter, Watch};
+use lightning::chain::{Filter, Watch};
 use lightning::ln::channelmanager;
 use lightning::ln::channelmanager::{
 	ChainParameters, ChannelManagerReadArgs, SimpleArcChannelManager,
@@ -458,7 +458,12 @@ async fn start_ldk() {
 	// Step 7: Read ChannelMonitor state from disk
 	let mut channelmonitors = persister.read_channelmonitors(keys_manager.clone()).unwrap();
 
-	// Step 8: Initialize the ChannelManager
+	// Step 8: Poll for the best chain tip, which may be used by the channel manager & spv client
+	let polled_chain_tip = init::validate_best_block_header(bitcoind_client.as_ref())
+		.await
+		.expect("Failed to fetch best block header and best block");
+
+	// Step 9: Initialize the ChannelManager
 	let mut user_config = UserConfig::default();
 	user_config.channel_handshake_limits.force_announced_channel_preference = false;
 	let mut restarting_node = true;
@@ -481,15 +486,11 @@ async fn start_ldk() {
 		} else {
 			// We're starting a fresh node.
 			restarting_node = false;
-			let getinfo_resp = bitcoind_client.get_blockchain_info().await;
-
-			let chain_params = ChainParameters {
-				network: args.network,
-				best_block: BestBlock::new(
-					getinfo_resp.latest_blockhash,
-					getinfo_resp.latest_height as u32,
-				),
-			};
+
+			let polled_best_block = polled_chain_tip.to_best_block();
+			let polled_best_block_hash = polled_best_block.block_hash();
+			let chain_params =
+				ChainParameters { network: args.network, best_block: polled_best_block };
 			let fresh_channel_manager = channelmanager::ChannelManager::new(
 				fee_estimator.clone(),
 				chain_monitor.clone(),
@@ -499,15 +500,14 @@ async fn start_ldk() {
 				user_config,
 				chain_params,
 			);
-			(getinfo_resp.latest_blockhash, fresh_channel_manager)
+			(polled_best_block_hash, fresh_channel_manager)
 		}
 	};
 
-	// Step 9: Sync ChannelMonitors and ChannelManager to chain tip
+	// Step 10: Sync ChannelMonitors and ChannelManager to chain tip
 	let mut chain_listener_channel_monitors = Vec::new();
 	let mut cache = UnboundedCache::new();
-	let mut chain_tip: Option<poll::ValidatedBlockHeader> = None;
-	if restarting_node {
+	let chain_tip = if restarting_node {
 		let mut chain_listeners = vec![(
 			channel_manager_blockhash,
 			&channel_manager as &(dyn chain::Listen + Send + Sync),
@@ -528,19 +528,20 @@ async fn start_ldk() {
 				&monitor_listener_info.1 as &(dyn chain::Listen + Send + Sync),
 			));
 		}
-		chain_tip = Some(
-			init::synchronize_listeners(
-				bitcoind_client.as_ref(),
-				args.network,
-				&mut cache,
-				chain_listeners,
-			)
-			.await
-			.unwrap(),
-		);
-	}
 
-	// Step 10: Give ChannelMonitors to ChainMonitor
+		init::synchronize_listeners(
+			bitcoind_client.as_ref(),
+			args.network,
+			&mut cache,
+			chain_listeners,
+		)
+		.await
+		.unwrap()
+	} else {
+		polled_chain_tip
+	};
+
+	// Step 11: Give ChannelMonitors to ChainMonitor
 	for item in chain_listener_channel_monitors.drain(..) {
 		let channel_monitor = item.1 .0;
 		let funding_outpoint = item.2;
@@ -550,7 +551,7 @@ async fn start_ldk() {
 		);
 	}
 
-	// Step 11: Optional: Initialize the P2PGossipSync
+	// Step 12: Optional: Initialize the P2PGossipSync
 	let genesis = genesis_block(args.network).header.block_hash();
 	let network_graph_path = format!("{}/network_graph", ldk_data_dir.clone());
 	let network_graph =
@@ -561,7 +562,7 @@ async fn start_ldk() {
 		logger.clone(),
 	));
 
-	// Step 12: Initialize the PeerManager
+	// Step 13: Initialize the PeerManager
 	let channel_manager: Arc<ChannelManager> = Arc::new(channel_manager);
 	let onion_messenger: Arc<OnionMessenger> = Arc::new(OnionMessenger::new(
 		Arc::clone(&keys_manager),
@@ -586,7 +587,7 @@ async fn start_ldk() {
 	));
 
 	// ## Running LDK
-	// Step 13: Initialize networking
+	// Step 14: Initialize networking
 
 	let peer_manager_connection_handler = peer_manager.clone();
 	let listening_port = args.ldk_peer_listening_port;
@@ -612,26 +613,22 @@ async fn start_ldk() {
 		}
 	});
 
-	// Step 14: Connect and Disconnect Blocks
-	if chain_tip.is_none() {
-		chain_tip = Some(init::validate_best_block_header(bitcoind_client.as_ref()).await.unwrap());
-	}
+	// Step 15: Connect and Disconnect Blocks
 	let channel_manager_listener = channel_manager.clone();
 	let chain_monitor_listener = chain_monitor.clone();
 	let bitcoind_block_source = bitcoind_client.clone();
 	let network = args.network;
 	tokio::spawn(async move {
 		let chain_poller = poll::ChainPoller::new(bitcoind_block_source.as_ref(), network);
 		let chain_listener = (chain_monitor_listener, channel_manager_listener);
-		let mut spv_client =
-			SpvClient::new(chain_tip.unwrap(), chain_poller, &mut cache, &chain_listener);
+		let mut spv_client = SpvClient::new(chain_tip, chain_poller, &mut cache, &chain_listener);
 		loop {
 			spv_client.poll_best_tip().await.unwrap();
 			tokio::time::sleep(Duration::from_secs(1)).await;
 		}
 	});
 
-	// Step 15: Handle LDK Events
+	// Step 16: Handle LDK Events
 	let channel_manager_event_listener = channel_manager.clone();
 	let keys_manager_listener = keys_manager.clone();
 	// TODO: persist payment info to disk
@@ -656,15 +653,15 @@ async fn start_ldk() {
 		));
 	};
 
-	// Step 16: Initialize routing ProbabilisticScorer
+	// Step 17: Initialize routing ProbabilisticScorer
 	let scorer_path = format!("{}/scorer", ldk_data_dir.clone());
 	let scorer = Arc::new(Mutex::new(disk::read_scorer(
 		Path::new(&scorer_path),
 		Arc::clone(&network_graph),
 		Arc::clone(&logger),
 	)));
 
-	// Step 17: Create InvoicePayer
+	// Step 18: Create InvoicePayer
 	let router = DefaultRouter::new(
 		network_graph.clone(),
 		logger.clone(),
@@ -679,10 +676,10 @@ async fn start_ldk() {
 		payment::Retry::Timeout(Duration::from_secs(10)),
 	));
 
-	// Step 18: Persist ChannelManager and NetworkGraph
+	// Step 19: Persist ChannelManager and NetworkGraph
 	let persister = Arc::new(FilesystemPersister::new(ldk_data_dir.clone()));
 
-	// Step 19: Background Processing
+	// Step 20: Background Processing
 	let background_processor = BackgroundProcessor::start(
 		persister,
 		invoice_payer.clone(),