Merge pull request #1029 from TheBlueMatt/2021-07-log-channel-close
[rust-lightning] / lightning / src / ln / channelmanager.rs
index c5db4075626fb93972037d10e1e5f60d68a57404..24c0c688cf0843274a61954433098d31324810a5 100644 (file)
@@ -60,10 +60,11 @@ use util::chacha20::{ChaCha20, ChaChaReader};
 use util::logger::{Logger, Level};
 use util::errors::APIError;
 
+use io;
 use prelude::*;
 use core::{cmp, mem};
 use core::cell::RefCell;
-use std::io::{Cursor, Read};
+use io::{Cursor, Read};
 use sync::{Arc, Condvar, Mutex, MutexGuard, RwLock, RwLockReadGuard};
 use core::sync::atomic::{AtomicUsize, Ordering};
 use core::time::Duration;
@@ -207,6 +208,14 @@ pub(super) enum HTLCFailReason {
        }
 }
 
+/// Return value for claim_funds_from_hop
+enum ClaimFundsFromHop {
+       PrevHopForceClosed,
+       MonitorUpdateFail(PublicKey, MsgHandleErrInternal, Option<u64>),
+       Success(u64),
+       DuplicateClaim,
+}
+
 type ShutdownResult = (Option<(OutPoint, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>);
 
 /// Error type returned across the channel_state mutex boundary. When an Err is generated for a
@@ -2787,16 +2796,22 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                         HTLCFailReason::Reason { failure_code: 0x4000|15, data: htlc_msat_height_data });
                                } else {
                                        match self.claim_funds_from_hop(channel_state.as_mut().unwrap(), htlc.prev_hop, payment_preimage) {
-                                               Err(Some(e)) => {
-                                                       if let msgs::ErrorAction::IgnoreError = e.1.err.action {
+                                               ClaimFundsFromHop::MonitorUpdateFail(pk, err, _) => {
+                                                       if let msgs::ErrorAction::IgnoreError = err.err.action {
                                                                // We got a temporary failure updating monitor, but will claim the
                                                                // HTLC when the monitor updating is restored (or on chain).
-                                                               log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", e.1.err.err);
+                                                               log_error!(self.logger, "Temporary failure claiming HTLC, treating as success: {}", err.err.err);
                                                                claimed_any_htlcs = true;
-                                                       } else { errs.push(e); }
+                                                       } else { errs.push((pk, err)); }
+                                               },
+                                               ClaimFundsFromHop::PrevHopForceClosed => unreachable!("We already checked for channel existence, we can't fail here!"),
+                                               ClaimFundsFromHop::DuplicateClaim => {
+                                                       // While we should never get here in most cases, if we do, it likely
+                                                       // indicates that the HTLC was timed out some time ago and is no longer
+                                                       // available to be claimed. Thus, it does not make sense to set
+                                                       // `claimed_any_htlcs`.
                                                },
-                                               Err(None) => unreachable!("We already checked for channel existence, we can't fail here!"),
-                                               Ok(()) => claimed_any_htlcs = true,
+                                               ClaimFundsFromHop::Success(_) => claimed_any_htlcs = true,
                                        }
                                }
                        }
@@ -2814,28 +2829,29 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                } else { false }
        }
 
-       fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<Signer>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> Result<(), Option<(PublicKey, MsgHandleErrInternal)>> {
+       fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<Signer>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> ClaimFundsFromHop {
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
                let channel_state = &mut **channel_state_lock;
                let chan_id = match channel_state.short_to_id.get(&prev_hop.short_channel_id) {
                        Some(chan_id) => chan_id.clone(),
                        None => {
-                               return Err(None)
+                               return ClaimFundsFromHop::PrevHopForceClosed
                        }
                };
 
                if let hash_map::Entry::Occupied(mut chan) = channel_state.by_id.entry(chan_id) {
                        match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
                                Ok(msgs_monitor_option) => {
-                                       if let UpdateFulfillCommitFetch::NewClaim { msgs, monitor_update } = msgs_monitor_option {
+                                       if let UpdateFulfillCommitFetch::NewClaim { msgs, htlc_value_msat, monitor_update } = msgs_monitor_option {
                                                if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
                                                        log_given_level!(self.logger, if e == ChannelMonitorUpdateErr::PermanentFailure { Level::Error } else { Level::Debug },
                                                                "Failed to update channel monitor with preimage {:?}: {:?}",
                                                                payment_preimage, e);
-                                                       return Err(Some((
+                                                       return ClaimFundsFromHop::MonitorUpdateFail(
                                                                chan.get().get_counterparty_node_id(),
                                                                handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err(),
-                                                       )));
+                                                               Some(htlc_value_msat)
+                                                       );
                                                }
                                                if let Some((msg, commitment_signed)) = msgs {
                                                        log_debug!(self.logger, "Claiming funds for HTLC with preimage {} resulted in a commitment_signed for channel {}",
@@ -2852,8 +2868,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                }
                                                        });
                                                }
+                                               return ClaimFundsFromHop::Success(htlc_value_msat);
+                                       } else {
+                                               return ClaimFundsFromHop::DuplicateClaim;
                                        }
-                                       return Ok(())
                                },
                                Err((e, monitor_update)) => {
                                        if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
@@ -2866,13 +2884,13 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        if drop {
                                                chan.remove_entry();
                                        }
-                                       return Err(Some((counterparty_node_id, res)));
+                                       return ClaimFundsFromHop::MonitorUpdateFail(counterparty_node_id, res, None);
                                },
                        }
                } else { unreachable!(); }
        }
 
-       fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage) {
+       fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage, forwarded_htlc_value_msat: Option<u64>, from_onchain: bool) {
                match source {
                        HTLCSource::OutboundRoute { session_priv, .. } => {
                                mem::drop(channel_state_lock);
@@ -2891,29 +2909,51 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        },
                        HTLCSource::PreviousHopData(hop_data) => {
                                let prev_outpoint = hop_data.outpoint;
-                               if let Err((counterparty_node_id, err)) = match self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage) {
-                                       Ok(()) => Ok(()),
-                                       Err(None) => {
-                                               let preimage_update = ChannelMonitorUpdate {
-                                                       update_id: CLOSED_CHANNEL_UPDATE_ID,
-                                                       updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
-                                                               payment_preimage: payment_preimage.clone(),
-                                                       }],
-                                               };
-                                               // We update the ChannelMonitor on the backward link, after
-                                               // receiving an offchain preimage event from the forward link (the
-                                               // event being update_fulfill_htlc).
-                                               if let Err(e) = self.chain_monitor.update_channel(prev_outpoint, preimage_update) {
-                                                       log_error!(self.logger, "Critical error: failed to update channel monitor with preimage {:?}: {:?}",
-                                                                  payment_preimage, e);
-                                               }
-                                               Ok(())
-                                       },
-                                       Err(Some(res)) => Err(res),
-                               } {
-                                       mem::drop(channel_state_lock);
-                                       let res: Result<(), _> = Err(err);
-                                       let _ = handle_error!(self, res, counterparty_node_id);
+                               let res = self.claim_funds_from_hop(&mut channel_state_lock, hop_data, payment_preimage);
+                               let claimed_htlc = if let ClaimFundsFromHop::DuplicateClaim = res { false } else { true };
+                               let htlc_claim_value_msat = match res {
+                                       ClaimFundsFromHop::MonitorUpdateFail(_, _, amt_opt) => amt_opt,
+                                       ClaimFundsFromHop::Success(amt) => Some(amt),
+                                       _ => None,
+                               };
+                               if let ClaimFundsFromHop::PrevHopForceClosed = res {
+                                       let preimage_update = ChannelMonitorUpdate {
+                                               update_id: CLOSED_CHANNEL_UPDATE_ID,
+                                               updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
+                                                       payment_preimage: payment_preimage.clone(),
+                                               }],
+                                       };
+                                       // We update the ChannelMonitor on the backward link, after
+                                       // receiving an offchain preimage event from the forward link (the
+                                       // event being update_fulfill_htlc).
+                                       if let Err(e) = self.chain_monitor.update_channel(prev_outpoint, preimage_update) {
+                                               log_error!(self.logger, "Critical error: failed to update channel monitor with preimage {:?}: {:?}",
+                                                                                        payment_preimage, e);
+                                       }
+                                       // Note that we do *not* set `claimed_htlc` to false here. In fact, this
+                                       // totally could be a duplicate claim, but we have no way of knowing
+                                       // without interrogating the `ChannelMonitor` we've provided the above
+                                       // update to. Instead, we simply document in `PaymentForwarded` that this
+                                       // can happen.
+                               }
+                               mem::drop(channel_state_lock);
+                               if let ClaimFundsFromHop::MonitorUpdateFail(pk, err, _) = res {
+                                       let result: Result<(), _> = Err(err);
+                                       let _ = handle_error!(self, result, pk);
+                               }
+
+                               if claimed_htlc {
+                                       if let Some(forwarded_htlc_value) = forwarded_htlc_value_msat {
+                                               let fee_earned_msat = if let Some(claimed_htlc_value) = htlc_claim_value_msat {
+                                                       Some(claimed_htlc_value - forwarded_htlc_value)
+                                               } else { None };
+
+                                               let mut pending_events = self.pending_events.lock().unwrap();
+                                               pending_events.push(events::Event::PaymentForwarded {
+                                                       fee_earned_msat,
+                                                       claim_from_onchain_tx: from_onchain,
+                                               });
+                                       }
                                }
                        },
                }
@@ -3309,7 +3349,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
        fn internal_update_fulfill_htlc(&self, counterparty_node_id: &PublicKey, msg: &msgs::UpdateFulfillHTLC) -> Result<(), MsgHandleErrInternal> {
                let mut channel_lock = self.channel_state.lock().unwrap();
-               let htlc_source = {
+               let (htlc_source, forwarded_htlc_value) = {
                        let channel_state = &mut *channel_lock;
                        match channel_state.by_id.entry(msg.channel_id) {
                                hash_map::Entry::Occupied(mut chan) => {
@@ -3321,7 +3361,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                hash_map::Entry::Vacant(_) => return Err(MsgHandleErrInternal::send_err_msg_no_close("Failed to find corresponding channel".to_owned(), msg.channel_id))
                        }
                };
-               self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone());
+               self.claim_funds_internal(channel_lock, htlc_source, msg.payment_preimage.clone(), Some(forwarded_htlc_value), false);
                Ok(())
        }
 
@@ -3688,14 +3728,14 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// Process pending events from the `chain::Watch`, returning whether any events were processed.
        fn process_pending_monitor_events(&self) -> bool {
                let mut failed_channels = Vec::new();
-               let pending_monitor_events = self.chain_monitor.release_pending_monitor_events();
+               let mut pending_monitor_events = self.chain_monitor.release_pending_monitor_events();
                let has_pending_monitor_events = !pending_monitor_events.is_empty();
-               for monitor_event in pending_monitor_events {
+               for monitor_event in pending_monitor_events.drain(..) {
                        match monitor_event {
                                MonitorEvent::HTLCEvent(htlc_update) => {
                                        if let Some(preimage) = htlc_update.payment_preimage {
                                                log_trace!(self.logger, "Claiming HTLC with preimage {} from our monitor", log_bytes!(preimage.0));
-                                               self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage);
+                                               self.claim_funds_internal(self.channel_state.lock().unwrap(), htlc_update.source, preimage, htlc_update.onchain_value_satoshis.map(|v| v * 1000), true);
                                        } else {
                                                log_trace!(self.logger, "Failing HTLC with hash {} from our monitor", log_bytes!(htlc_update.payment_hash.0));
                                                self.fail_htlc_backwards_internal(self.channel_state.lock().unwrap(), htlc_update.source, &htlc_update.payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() });
@@ -3990,7 +4030,7 @@ where
                                result = NotifyOption::DoPersist;
                        }
 
-                       let mut pending_events = std::mem::replace(&mut *self.pending_events.lock().unwrap(), vec![]);
+                       let mut pending_events = mem::replace(&mut *self.pending_events.lock().unwrap(), vec![]);
                        if !pending_events.is_empty() {
                                result = NotifyOption::DoPersist;
                        }
@@ -4610,7 +4650,7 @@ impl_writeable_tlv_based!(HTLCPreviousHopData, {
 });
 
 impl Writeable for ClaimableHTLC {
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
                let payment_data = match &self.onion_payload {
                        OnionPayload::Invoice(data) => Some(data.clone()),
                        _ => None,
@@ -4714,7 +4754,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable f
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
                let _consistency_lock = self.total_consistency_lock.write().unwrap();
 
                write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
@@ -4910,7 +4950,7 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       fn read<R: ::std::io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
+       fn read<R: io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
                let (blockhash, chan_manager) = <(BlockHash, ChannelManager<Signer, M, T, K, F, L>)>::read(reader, args)?;
                Ok((blockhash, Arc::new(chan_manager)))
        }
@@ -4924,7 +4964,7 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       fn read<R: ::std::io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
+       fn read<R: io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
                let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
 
                let genesis_hash: BlockHash = Readable::read(reader)?;