-f inbound htlc, autoclose only if pending payment

Author: Antoine Riard

lightning/src/ln/channel.rs

@@ -27,7 +27,7 @@ use ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures};
 use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
 use ln::script::{self, ShutdownScript};
-use ln::channelmanager::{CounterpartyForwardingInfo, PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
+use ln::channelmanager::{CounterpartyForwardingInfo, PendingHTLCStatus, PendingInboundPayment, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, BREAKDOWN_TIMEOUT, MIN_CLTV_EXPIRY_DELTA, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys, CommitmentTransaction, HolderCommitmentTransaction, ChannelTransactionParameters, CounterpartyChannelTransactionParameters, MAX_HTLCS, get_commitment_transaction_number_obscure_factor, ClosingTransaction};
 use ln::chan_utils;
 use chain::BestBlock;
@@ -47,7 +47,7 @@ use prelude::*;
 use core::{cmp,mem,fmt};
 use core::ops::Deref;
 #[cfg(any(test, feature = "fuzztarget", debug_assertions))]
-use sync::Mutex;
+use sync::{Mutex, MutexGuard};
 use bitcoin::hashes::hex::ToHex;
 
 #[cfg(test)]
@@ -3398,7 +3398,7 @@ impl<Signer: Sign> Channel<Signer> {
 	/// If the auto-close timer is reached following the triggering of a auto-close condition
 	/// (i.e a non-satisfying feerate to ensure efficient confirmation), we force-close
 	/// channel, hopefully narrowing the safety risks for the user funds.
-	pub fn check_autoclose(&mut self, new_feerate: u32) -> Result<(), ChannelError> {
+	pub fn check_autoclose(&mut self, new_feerate: u32, pending_inbound_payments: MutexGuard<HashMap<PaymentHash, PendingInboundPayment>>) -> Result<(), ChannelError> {
 		if self.autoclose_timer	> 0 && self.autoclose_timer < AUTOCLOSE_TIMEOUT {
 			// Again, check at each autoclose tick that mempool feerate hasn't fall back
 			// more in-sync to the current channel feerate. Otherwise, reset autoclose
@@ -3410,10 +3410,18 @@ impl<Signer: Sign> Channel<Signer> {
 			}
 		}
 		if self.autoclose_timer == AUTOCLOSE_TIMEOUT {
-			let inbound_stats = self.get_inbound_pending_htlc_stats(None);
+			let mut pending_inbound = false;
+			for htlc in self.pending_inbound_htlcs.iter() {
+				let exposure_dust_limit_success_sats = (self.get_dust_buffer_feerate(None) as u64 * HTLC_SUCCESS_TX_WEIGHT / 1000) + self.holder_dust_limit_satoshis;
+				if htlc.amount_msat / 1000 > exposure_dust_limit_success_sats {
+					if pending_inbound_payments.get(&htlc.payment_hash).is_some() {
+						pending_inbound = true;
+					}
+				}
+			}
 			let outbound_stats = self.get_outbound_pending_htlc_stats(None);
 			// If the channel has pending *included* HTLCs to claim on-chain and `should_autoclose`=y, close the channel
-			if inbound_stats.on_holder_tx_included_htlcs + outbound_stats.on_holder_tx_included_htlcs > 0 && self.config.should_autoclose {
+			if (outbound_stats.on_holder_tx_included_htlcs > 0 || pending_inbound) && self.config.should_autoclose {
 				return Err(ChannelError::Close("Channel has time-sensitive outputs and the auto-close timer has been reached".to_owned()));
 			}
 			// Otherwise, do not reset the autoclose timer as a substantial HTLC can be committed

lightning/src/ln/channelmanager.rs

@@ -416,7 +416,7 @@ struct PeerState {
 ///
 /// Note that this struct will be removed entirely soon, in favor of storing no inbound payment data
 /// and instead encoding it in the payment secret.
-struct PendingInboundPayment {
+pub(crate) struct PendingInboundPayment {
 	/// The payment secret that the sender must use for us to accept this payment
 	payment_secret: PaymentSecret,
 	/// Time at which this HTLC expires - blocks with a header time above this value will result in
@@ -3089,15 +3089,17 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
 					let mut retain_channel = true;
 					let mut chan_needs_persist = NotifyOption::SkipPersist;
-					let res = match chan.check_autoclose(new_feerate) {
-						Ok(res) => Ok(res),
-						Err(e) => {
-							let (drop, res) = convert_chan_err!(self, e, short_to_id, chan, chan_id);
-							if drop {
-								retain_channel = false;
-								chan_needs_persist = NotifyOption::DoPersist;
+					let res = {
+						match chan.check_autoclose(new_feerate, self.pending_inbound_payments.lock().unwrap()) {
+							Ok(res) => Ok(res),
+							Err(e) => {
+								let (drop, res) = convert_chan_err!(self, e, short_to_id, chan, chan_id);
+								if drop {
+									retain_channel = false;
+									chan_needs_persist = NotifyOption::DoPersist;
+								}
+								Err(res)
 							}
-							Err(res)
 						}
 					};