Add getter for Minimum Relay Fee in FeeEstimator

We need to ensure that we respect minrelayfee when computing
RBF bumped fee.

Author: Antoine Riard

fuzz/fuzz_targets/chanmon_fail_consistency.rs

@@ -59,6 +59,9 @@ impl FeeEstimator for FuzzEstimator {
 	fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u64 {
 		253
 	}
+	fn get_min_relay_sat_per_1000_weight(&self) -> u64 {
+		0
+	}
 }
 
 pub struct TestBroadcaster {}

fuzz/fuzz_targets/full_stack_target.rs

@@ -112,6 +112,12 @@ impl FeeEstimator for FuzzEstimator {
 			None => 0
 		}
 	}
+	fn get_min_relay_sat_per_1000_weight(&self) -> u64 {
+		match self.input.get_slice(2) {
+			Some(slice) => cmp::max(slice_to_be16(slice) as u64, 20),
+			None => 0
+		}
+	}
 }
 
 struct TestBroadcaster {}

src/chain/chaininterface.rs

@@ -109,6 +109,11 @@ pub trait FeeEstimator: Sync + Send {
 	///  * satoshis-per-byte * 250
 	///  * ceil(satoshis-per-kbyte / 4)
 	fn get_est_sat_per_1000_weight(&self, confirmation_target: ConfirmationTarget) -> u64;
+	/// Gets satoshis of minimum relay fee required per 1000 Weight-Units.
+	///
+	/// Give us back the minimum relay fee setup by node mempool. It's should be accounted in generic fee
+	/// computation but in case of RBF we need more granularity on fee composition.
+	fn get_min_relay_sat_per_1000_weight(&self) -> u64;
 }
 
 /// Utility for tracking registered txn/outpoints and checking for matches

src/ln/channel.rs

@@ -3999,12 +3999,16 @@ mod tests {
 	use std::sync::Arc;
 
 	struct TestFeeEstimator {
-		fee_est: u64
+		fee_est: u64,
+		minrelayfee: u64
 	}
 	impl FeeEstimator for TestFeeEstimator {
 		fn get_est_sat_per_1000_weight(&self, _: ConfirmationTarget) -> u64 {
 			self.fee_est
 		}
+		fn get_min_relay_sat_per_1000_weight(&self) -> u64 {
+			self.minrelayfee
+		}
 	}
 
 	#[test]
@@ -4039,7 +4043,7 @@ mod tests {
 	#[test]
 	fn outbound_commitment_test() {
 		// Test vectors from BOLT 3 Appendix C:
-		let feeest = TestFeeEstimator{fee_est: 15000};
+		let feeest = TestFeeEstimator{fee_est: 15000, minrelayfee: 0};
 		let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
 		let secp_ctx = Secp256k1::new();
 

src/ln/functional_test_utils.rs

@@ -837,7 +837,7 @@ pub fn create_network(node_count: usize) -> Vec<Node> {
 
 	for i in 0..node_count {
 		let logger: Arc<Logger> = Arc::new(test_utils::TestLogger::with_id(format!("node {}", i)));
-		let feeest = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 });
+		let feeest = Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0});
 		let chain_monitor = Arc::new(chaininterface::ChainWatchInterfaceUtil::new(Network::Testnet, Arc::clone(&logger)));
 		let tx_broadcaster = Arc::new(test_utils::TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new())});
 		let mut seed = [0; 32];

src/ln/functional_tests.rs

@@ -3218,7 +3218,7 @@ fn test_no_txn_manager_serialize_deserialize() {
 	let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
 	nodes[0].chan_monitor.simple_monitor.monitors.lock().unwrap().iter().next().unwrap().1.write_for_disk(&mut chan_0_monitor_serialized).unwrap();
 
-	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 })));
+	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0})));
 	let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
 	let (_, chan_0_monitor) = <(Sha256dHash, ChannelMonitor)>::read(&mut chan_0_monitor_read, Arc::new(test_utils::TestLogger::new())).unwrap();
 	assert!(chan_0_monitor_read.is_empty());
@@ -3232,7 +3232,7 @@ fn test_no_txn_manager_serialize_deserialize() {
 		<(Sha256dHash, ChannelManager)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
 			default_config: config,
 			keys_manager,
-			fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 }),
+			fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0}),
 			monitor: nodes[0].chan_monitor.clone(),
 			chain_monitor: nodes[0].chain_monitor.clone(),
 			tx_broadcaster: nodes[0].tx_broadcaster.clone(),
@@ -3284,7 +3284,7 @@ fn test_simple_manager_serialize_deserialize() {
 	let mut chan_0_monitor_serialized = test_utils::TestVecWriter(Vec::new());
 	nodes[0].chan_monitor.simple_monitor.monitors.lock().unwrap().iter().next().unwrap().1.write_for_disk(&mut chan_0_monitor_serialized).unwrap();
 
-	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 })));
+	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0})));
 	let mut chan_0_monitor_read = &chan_0_monitor_serialized.0[..];
 	let (_, chan_0_monitor) = <(Sha256dHash, ChannelMonitor)>::read(&mut chan_0_monitor_read, Arc::new(test_utils::TestLogger::new())).unwrap();
 	assert!(chan_0_monitor_read.is_empty());
@@ -3297,7 +3297,7 @@ fn test_simple_manager_serialize_deserialize() {
 		<(Sha256dHash, ChannelManager)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
 			default_config: UserConfig::new(),
 			keys_manager,
-			fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 }),
+			fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0}),
 			monitor: nodes[0].chan_monitor.clone(),
 			chain_monitor: nodes[0].chain_monitor.clone(),
 			tx_broadcaster: nodes[0].tx_broadcaster.clone(),
@@ -3344,7 +3344,7 @@ fn test_manager_serialize_deserialize_inconsistent_monitor() {
 		node_0_monitors_serialized.push(writer.0);
 	}
 
-	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 })));
+	nodes[0].chan_monitor = Arc::new(test_utils::TestChannelMonitor::new(nodes[0].chain_monitor.clone(), nodes[0].tx_broadcaster.clone(), Arc::new(test_utils::TestLogger::new()), Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0})));
 	let mut node_0_monitors = Vec::new();
 	for serialized in node_0_monitors_serialized.iter() {
 		let mut read = &serialized[..];
@@ -3358,7 +3358,7 @@ fn test_manager_serialize_deserialize_inconsistent_monitor() {
 	let (_, nodes_0_deserialized) = <(Sha256dHash, ChannelManager)>::read(&mut nodes_0_read, ChannelManagerReadArgs {
 		default_config: UserConfig::new(),
 		keys_manager,
-		fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253 }),
+		fee_estimator: Arc::new(test_utils::TestFeeEstimator { sat_per_kw: 253, min_relay_sat_per_kw: 0}),
 		monitor: nodes[0].chan_monitor.clone(),
 		chain_monitor: nodes[0].chain_monitor.clone(),
 		tx_broadcaster: nodes[0].tx_broadcaster.clone(),

src/util/test_utils.rs

@@ -33,11 +33,15 @@ impl Writer for TestVecWriter {
 
 pub struct TestFeeEstimator {
 	pub sat_per_kw: u64,
+	pub min_relay_sat_per_kw: u64
 }
 impl chaininterface::FeeEstimator for TestFeeEstimator {
 	fn get_est_sat_per_1000_weight(&self, _confirmation_target: ConfirmationTarget) -> u64 {
 		self.sat_per_kw
 	}
+	fn get_min_relay_sat_per_1000_weight(&self) -> u64 {
+		self.min_relay_sat_per_kw
+	}
 }
 
 pub struct TestChannelMonitor {