Merge pull request #1119 from TheBlueMatt/2021-10-less-aggressive-htlc-timeouts

[rust-lightning] / lightning / src / ln / channel.rs

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index e39478bd740c063ce1f29a7dc853238ec75fcf48..2976882c8dd5888ec0e1f0fdc6b74ef5d008e892 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -32,7 +32,7 @@ use ln::chan_utils::{CounterpartyCommitmentSecrets, TxCreationKeys, HTLCOutputIn
 use ln::chan_utils;
 use chain::BestBlock;
 use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
-use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};
+use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS};
 use chain::transaction::{OutPoint, TransactionData};
 use chain::keysinterface::{Sign, KeysInterface};
 use util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
@@ -4197,7 +4197,10 @@ impl<Signer: Sign> Channel<Signer> {
        pub fn best_block_updated<L: Deref>(&mut self, height: u32, highest_header_time: u32, logger: &L)
                        -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> where L::Target: Logger {
                let mut timed_out_htlcs = Vec::new();
-               let unforwarded_htlc_cltv_limit = height + HTLC_FAIL_BACK_BUFFER;
+               // This mirrors the check in ChannelManager::decode_update_add_htlc_onion, refusing to
+               // forward an HTLC when our counterparty should almost certainly just fail it for expiring
+               // ~now.
+               let unforwarded_htlc_cltv_limit = height + LATENCY_GRACE_PERIOD_BLOCKS;
                self.holding_cell_htlc_updates.retain(|htlc_update| {
                        match htlc_update {
                                &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {