Merge pull request #1353 from dunxen/2022-03-mpp-receive-timeout

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

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index bf01ee1953cfcc37b8caacd1836199d1b47cd175..2b10fad53976d90667010cefbeb3f582e9514343 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -441,6 +441,7 @@ struct ClaimableHTLC {
        cltv_expiry: u32,
        value: u64,
        onion_payload: OnionPayload,
+       timer_ticks: u8,
 }
 
 /// A payment identifier used to uniquely identify a payment to LDK.
@@ -1148,6 +1149,9 @@ const CHECK_CLTV_EXPIRY_SANITY_2: u32 = MIN_CLTV_EXPIRY_DELTA as u32 - LATENCY_G
 /// pending HTLCs in flight.
 pub(crate) const PAYMENT_EXPIRY_BLOCKS: u32 = 3;
 
+/// The number of ticks of [`ChannelManager::timer_tick_occurred`] until expiry of incomplete MPPs
+pub(crate) const MPP_TIMEOUT_TICKS: u8 = 3;
+
 /// Information needed for constructing an invoice route hint for this channel.
 #[derive(Clone, Debug, PartialEq)]
 pub struct CounterpartyForwardingInfo {
@@ -3326,6 +3330,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                                phantom_shared_secret,
                                                                        },
                                                                        value: amt_to_forward,
+                                                                       timer_ticks: 0,
                                                                        cltv_expiry,
                                                                        onion_payload,
                                                                };
@@ -3620,6 +3625,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        let new_feerate = self.fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 
                        let mut handle_errors = Vec::new();
+                       let mut timed_out_mpp_htlcs = Vec::new();
                        {
                                let mut channel_state_lock = self.channel_state.lock().unwrap();
                                let channel_state = &mut *channel_state_lock;
@@ -3668,6 +3674,32 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                                        true
                                });
+
+                               channel_state.claimable_htlcs.retain(|payment_hash, htlcs| {
+                                       if htlcs.is_empty() {
+                                               // This should be unreachable
+                                               debug_assert!(false);
+                                               return false;
+                                       }
+                                       if let OnionPayload::Invoice(ref final_hop_data) = htlcs[0].onion_payload {
+                                               // Check if we've received all the parts we need for an MPP (the value of the parts adds to total_msat).
+                                               // In this case we're not going to handle any timeouts of the parts here.
+                                               if final_hop_data.total_msat == htlcs.iter().fold(0, |total, htlc| total + htlc.value) {
+                                                       return true;
+                                               } else if htlcs.into_iter().any(|htlc| {
+                                                       htlc.timer_ticks += 1;
+                                                       return htlc.timer_ticks >= MPP_TIMEOUT_TICKS
+                                               }) {
+                                                       timed_out_mpp_htlcs.extend(htlcs.into_iter().map(|htlc| (htlc.prev_hop.clone(), payment_hash.clone())));
+                                                       return false;
+                                               }
+                                       }
+                                       true
+                               });
+                       }
+
+                       for htlc_source in timed_out_mpp_htlcs.drain(..) {
+                               self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), HTLCSource::PreviousHopData(htlc_source.0), &htlc_source.1, HTLCFailReason::Reason { failure_code: 23, data: Vec::new() });
                        }
 
                        for (err, counterparty_node_id) in handle_errors.drain(..) {
@@ -6240,6 +6272,7 @@ impl Readable for ClaimableHTLC {
                };
                Ok(Self {
                        prev_hop: prev_hop.0.unwrap(),
+                       timer_ticks: 0,
                        value,
                        onion_payload,
                        cltv_expiry,