Time out AwatingRemoteRAA outgoing HTLCs when we reach cltv_expiry

In case of committing out-of-time outgoing HTLCs, we force
ourselves to close the channel to avoid remote peer claims on a
non-backed HTLC

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index ac072c0ea4f4f3de84fa6ca2fcfcfeda16085930..f44109432a581c2f28a7b3797cc187d24546ed31 100644 (file)
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -18,7 +18,7 @@ use secp256k1;
 use ln::features::{ChannelFeatures, InitFeatures};
 use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};
 use ln::features::{ChannelFeatures, InitFeatures};
 use ln::msgs;
 use ln::msgs::{DecodeError, OptionalField, DataLossProtect};

-use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep};
+use ln::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER};

 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 use ln::chan_utils::{CounterpartyCommitmentSecrets, LocalCommitmentTransaction, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys};
 use ln::chan_utils;
 use ln::channelmanager::{PendingHTLCStatus, HTLCSource, HTLCFailReason, HTLCFailureMsg, PendingHTLCInfo, RAACommitmentOrder, PaymentPreimage, PaymentHash, BREAKDOWN_TIMEOUT, MAX_LOCAL_BREAKDOWN_TIMEOUT};
 use ln::chan_utils::{CounterpartyCommitmentSecrets, LocalCommitmentTransaction, TxCreationKeys, HTLCOutputInCommitment, HTLC_SUCCESS_TX_WEIGHT, HTLC_TIMEOUT_TX_WEIGHT, make_funding_redeemscript, ChannelPublicKeys};
 use ln::chan_utils;


@@ -3154,13 +3154,33 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                self.network_sync == UpdateStatus::DisabledMarked
        }
 
                self.network_sync == UpdateStatus::DisabledMarked
        }
 

-       /// Called by channelmanager based on chain blocks being connected.
-       /// Note that we only need to use this to detect funding_signed, anything else is handled by
-       /// the channel_monitor.
-       /// In case of Err, the channel may have been closed, at which point the standard requirements
-       /// apply - no calls may be made except those explicitly stated to be allowed post-shutdown.
+       /// When we receive a new block, we (a) check whether the block contains the funding
+       /// transaction (which would start us counting blocks until we send the funding_signed), and
+       /// (b) check the height of the block against outbound holding cell HTLCs in case we need to
+       /// give up on them prematurely and time them out. Everything else (e.g. commitment
+       /// transaction broadcasts, channel closure detection, HTLC transaction broadcasting, etc) is
+       /// handled by the ChannelMonitor.
+       ///
+       /// If we return Err, the channel may have been closed, at which point the standard
+       /// requirements apply - no calls may be made except those explicitly stated to be allowed
+       /// post-shutdown.

        /// Only returns an ErrorAction of DisconnectPeer, if Err.
        /// Only returns an ErrorAction of DisconnectPeer, if Err.

-       pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) -> Result<Option<msgs::FundingLocked>, msgs::ErrorMessage> {
+       ///
+       /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
+       /// back.
+       pub fn block_connected(&mut self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], indexes_of_txn_matched: &[u32]) -> Result<(Option<msgs::FundingLocked>, Vec<(HTLCSource, PaymentHash)>), msgs::ErrorMessage> {
+               let mut timed_out_htlcs = Vec::new();
+               self.holding_cell_htlc_updates.retain(|htlc_update| {
+                       match htlc_update {
+                               &HTLCUpdateAwaitingACK::AddHTLC { ref payment_hash, ref source, ref cltv_expiry, .. } => {
+                                       if *cltv_expiry <= height + HTLC_FAIL_BACK_BUFFER {
+                                               timed_out_htlcs.push((source.clone(), payment_hash.clone()));
+                                               false
+                                       } else { true }
+                               },
+                               _ => true
+                       }
+               });

                let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
                if header.bitcoin_hash() != self.last_block_connected {
                        if self.funding_tx_confirmations > 0 {
                let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
                if header.bitcoin_hash() != self.last_block_connected {
                        if self.funding_tx_confirmations > 0 {


@@ -3243,19 +3263,19 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
                                                if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
                                                        let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
                                                        let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);
                                                if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
                                                        let next_per_commitment_secret = self.build_local_commitment_secret(self.cur_local_commitment_transaction_number);
                                                        let next_per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &next_per_commitment_secret);

-                                                       return Ok(Some(msgs::FundingLocked {
+                                                       return Ok((Some(msgs::FundingLocked {

                                                                channel_id: self.channel_id,
                                                                next_per_commitment_point: next_per_commitment_point,
                                                                channel_id: self.channel_id,
                                                                next_per_commitment_point: next_per_commitment_point,

-                                                       }));
+                                                       }), timed_out_htlcs));

                                                } else {
                                                        self.monitor_pending_funding_locked = true;
                                                } else {
                                                        self.monitor_pending_funding_locked = true;

-                                                       return Ok(None);
+                                                       return Ok((None, timed_out_htlcs));

                                                }
                                        }
                                }
                        }
                }
                                                }
                                        }
                                }
                        }
                }

-               Ok(None)
+               Ok((None, timed_out_htlcs))

        }
 
        /// Called by channelmanager based on chain blocks being disconnected.
        }
 
        /// Called by channelmanager based on chain blocks being disconnected.

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index 6835522241bc0337238821b9549e1a969a69c016..cbcccb82f933f7416c7ad5a44e3a5c196ec51391 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -2962,23 +2962,32 @@ impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K:
                        let short_to_id = &mut channel_state.short_to_id;
                        let pending_msg_events = &mut channel_state.pending_msg_events;
                        channel_state.by_id.retain(|_, channel| {
                        let short_to_id = &mut channel_state.short_to_id;
                        let pending_msg_events = &mut channel_state.pending_msg_events;
                        channel_state.by_id.retain(|_, channel| {

-                               let chan_res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
-                               if let Ok(Some(funding_locked)) = chan_res {
-                                       pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {
-                                               node_id: channel.get_their_node_id(),
-                                               msg: funding_locked,
-                                       });
-                                       if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
-                                               log_trace!(self, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
-                                               pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
+                               let res = channel.block_connected(header, height, txn_matched, indexes_of_txn_matched);
+                               if let Ok((chan_res, mut timed_out_pending_htlcs)) = res {
+                                       for (source, payment_hash) in timed_out_pending_htlcs.drain(..) {
+                                               let chan_update = self.get_channel_update(&channel).map(|u| u.encode_with_len()).unwrap(); // Cannot add/recv HTLCs before we have a short_id so unwrap is safe
+                                               timed_out_htlcs.push((source, payment_hash,  HTLCFailReason::Reason {
+                                                       failure_code: 0x1000 | 14, // expiry_too_soon, or at least it is now
+                                                       data: chan_update,
+                                               }));
+                                       }
+                                       if let Some(funding_locked) = chan_res {
+                                               pending_msg_events.push(events::MessageSendEvent::SendFundingLocked {

                                                        node_id: channel.get_their_node_id(),
                                                        node_id: channel.get_their_node_id(),

-                                                       msg: announcement_sigs,
+                                                       msg: funding_locked,

                                                });
                                                });

-                                       } else {
-                                               log_trace!(self, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
+                                               if let Some(announcement_sigs) = self.get_announcement_sigs(channel) {
+                                                       log_trace!(self, "Sending funding_locked and announcement_signatures for {}", log_bytes!(channel.channel_id()));
+                                                       pending_msg_events.push(events::MessageSendEvent::SendAnnouncementSignatures {
+                                                               node_id: channel.get_their_node_id(),
+                                                               msg: announcement_sigs,
+                                                       });
+                                               } else {
+                                                       log_trace!(self, "Sending funding_locked WITHOUT announcement_signatures for {}", log_bytes!(channel.channel_id()));
+                                               }
+                                               short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());

                                        }
                                        }

-                                       short_to_id.insert(channel.get_short_channel_id().unwrap(), channel.channel_id());
-                               } else if let Err(e) = chan_res {
+                               } else if let Err(e) = res {

                                        pending_msg_events.push(events::MessageSendEvent::HandleError {
                                                node_id: channel.get_their_node_id(),
                                                action: msgs::ErrorAction::SendErrorMessage { msg: e },
                                        pending_msg_events.push(events::MessageSendEvent::HandleError {
                                                node_id: channel.get_their_node_id(),
                                                action: msgs::ErrorAction::SendErrorMessage { msg: e },


@@ -3049,8 +3058,6 @@ impl<ChanSigner: ChannelKeys, M: Deref + Sync + Send, T: Deref + Sync + Send, K:
                }
 
                for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {
                }
 
                for (source, payment_hash, reason) in timed_out_htlcs.drain(..) {

-                       // Call it incorrect_or_unknown_payment_details as the issue, ultimately, is that the
-                       // user failed to provide us a preimage within the cltv_expiry time window.

                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
                }
                self.latest_block_height.store(height as usize, Ordering::Release);
                        self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), source, &payment_hash, reason);
                }
                self.latest_block_height.store(height as usize, Ordering::Release);