Move pending-HTLC-updated ChannelMonitor from ManyChannelMonitor
[rust-lightning] / lightning / src / ln / channelmonitor.rs
index 68674ac3ae098c3db7d70a173755e44232c77c44..eaf207cd2745b49c54d2141ebdf16ab5fdc048f1 100644 (file)
@@ -93,11 +93,13 @@ pub struct MonitorUpdateError(pub &'static str);
 
 /// Simple structure send back by ManyChannelMonitor in case of HTLC detected onchain from a
 /// forward channel and from which info are needed to update HTLC in a backward channel.
+#[derive(Clone, PartialEq)]
 pub struct HTLCUpdate {
        pub(super) payment_hash: PaymentHash,
        pub(super) payment_preimage: Option<PaymentPreimage>,
        pub(super) source: HTLCSource
 }
+impl_writeable!(HTLCUpdate, 0, { payment_hash, payment_preimage, source });
 
 /// Simple trait indicating ability to track a set of ChannelMonitors and multiplex events between
 /// them. Generally should be implemented by keeping a local SimpleManyChannelMonitor and passing
@@ -130,8 +132,12 @@ pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
        fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr>;
 
        /// Used by ChannelManager to get list of HTLC resolved onchain and which needed to be updated
-       /// with success or failure backward
-       fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate>;
+       /// with success or failure.
+       ///
+       /// You should probably just call through to
+       /// ChannelMonitor::get_and_clear_pending_htlcs_updated() for each ChannelMonitor and return
+       /// the full list.
+       fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate>;
 }
 
 /// A simple implementation of a ManyChannelMonitor and ChainListener. Can be used to create a
@@ -153,7 +159,6 @@ pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys> {
        chain_monitor: Arc<ChainWatchInterface>,
        broadcaster: Arc<BroadcasterInterface>,
        pending_events: Mutex<Vec<events::Event>>,
-       pending_htlc_updated: Mutex<HashMap<PaymentHash, Vec<(HTLCSource, Option<PaymentPreimage>)>>>,
        logger: Arc<Logger>,
        fee_estimator: Arc<FeeEstimator>
 }
@@ -162,11 +167,10 @@ impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys> ChainListen
        fn block_connected(&self, header: &BlockHeader, height: u32, txn_matched: &[&Transaction], _indexes_of_txn_matched: &[u32]) {
                let block_hash = header.bitcoin_hash();
                let mut new_events: Vec<events::Event> = Vec::with_capacity(0);
-               let mut htlc_updated_infos = Vec::new();
                {
                        let mut monitors = self.monitors.lock().unwrap();
                        for monitor in monitors.values_mut() {
-                               let (txn_outputs, spendable_outputs, mut htlc_updated) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
+                               let (txn_outputs, spendable_outputs) = monitor.block_connected(txn_matched, height, &block_hash, &*self.broadcaster, &*self.fee_estimator);
                                if spendable_outputs.len() > 0 {
                                        new_events.push(events::Event::SpendableOutputs {
                                                outputs: spendable_outputs,
@@ -178,35 +182,6 @@ impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys> ChainListen
                                                self.chain_monitor.install_watch_outpoint((txid.clone(), idx as u32), &output.script_pubkey);
                                        }
                                }
-                               htlc_updated_infos.append(&mut htlc_updated);
-                       }
-               }
-               {
-                       // ChannelManager will just need to fetch pending_htlc_updated and pass state backward
-                       let mut pending_htlc_updated = self.pending_htlc_updated.lock().unwrap();
-                       for htlc in htlc_updated_infos.drain(..) {
-                               match pending_htlc_updated.entry(htlc.2) {
-                                       hash_map::Entry::Occupied(mut e) => {
-                                               // In case of reorg we may have htlc outputs solved in a different way so
-                                               // we prefer to keep claims but don't store duplicate updates for a given
-                                               // (payment_hash, HTLCSource) pair.
-                                               let mut existing_claim = false;
-                                               e.get_mut().retain(|htlc_data| {
-                                                       if htlc.0 == htlc_data.0 {
-                                                               if htlc_data.1.is_some() {
-                                                                       existing_claim = true;
-                                                                       true
-                                                               } else { false }
-                                                       } else { true }
-                                               });
-                                               if !existing_claim {
-                                                       e.get_mut().push((htlc.0, htlc.1));
-                                               }
-                                       }
-                                       hash_map::Entry::Vacant(e) => {
-                                               e.insert(vec![(htlc.0, htlc.1)]);
-                                       }
-                               }
                        }
                }
                let mut pending_events = self.pending_events.lock().unwrap();
@@ -231,7 +206,6 @@ impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys> Simpl
                        chain_monitor,
                        broadcaster,
                        pending_events: Mutex::new(Vec::new()),
-                       pending_htlc_updated: Mutex::new(HashMap::new()),
                        logger,
                        fee_estimator: feeest,
                };
@@ -284,17 +258,10 @@ impl<ChanSigner: ChannelKeys> ManyChannelMonitor<ChanSigner> for SimpleManyChann
                }
        }
 
-       fn fetch_pending_htlc_updated(&self) -> Vec<HTLCUpdate> {
-               let mut updated = self.pending_htlc_updated.lock().unwrap();
-               let mut pending_htlcs_updated = Vec::with_capacity(updated.len());
-               for (k, v) in updated.drain() {
-                       for htlc_data in v {
-                               pending_htlcs_updated.push(HTLCUpdate {
-                                       payment_hash: k,
-                                       payment_preimage: htlc_data.1,
-                                       source: htlc_data.0,
-                               });
-                       }
+       fn get_and_clear_pending_htlcs_updated(&self) -> Vec<HTLCUpdate> {
+               let mut pending_htlcs_updated = Vec::new();
+               for chan in self.monitors.lock().unwrap().values_mut() {
+                       pending_htlcs_updated.append(&mut chan.get_and_clear_pending_htlcs_updated());
                }
                pending_htlcs_updated
        }
@@ -640,6 +607,8 @@ pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
 
        payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
 
+       pending_htlcs_updated: Vec<HTLCUpdate>,
+
        destination_script: Script,
        // Thanks to data loss protection, we may be able to claim our non-htlc funds
        // back, this is the script we have to spend from but we need to
@@ -750,6 +719,7 @@ impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
                        self.current_remote_commitment_number != other.current_remote_commitment_number ||
                        self.current_local_signed_commitment_tx != other.current_local_signed_commitment_tx ||
                        self.payment_preimages != other.payment_preimages ||
+                       self.pending_htlcs_updated != other.pending_htlcs_updated ||
                        self.destination_script != other.destination_script ||
                        self.to_remote_rescue != other.to_remote_rescue ||
                        self.pending_claim_requests != other.pending_claim_requests ||
@@ -938,6 +908,11 @@ impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
                        writer.write_all(&payment_preimage.0[..])?;
                }
 
+               writer.write_all(&byte_utils::be64_to_array(self.pending_htlcs_updated.len() as u64))?;
+               for data in self.pending_htlcs_updated.iter() {
+                       data.write(writer)?;
+               }
+
                self.last_block_hash.write(writer)?;
                self.destination_script.write(writer)?;
                if let Some((ref to_remote_script, ref local_key)) = self.to_remote_rescue {
@@ -1056,6 +1031,8 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                        current_remote_commitment_number: 1 << 48,
 
                        payment_preimages: HashMap::new(),
+                       pending_htlcs_updated: Vec::new(),
+
                        destination_script: destination_script,
                        to_remote_rescue: None,
 
@@ -1419,6 +1396,14 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                res
        }
 
+       /// Get the list of HTLCs who's status has been updated on chain. This should be called by
+       /// ChannelManager via ManyChannelMonitor::get_and_clear_pending_htlcs_updated().
+       pub fn get_and_clear_pending_htlcs_updated(&mut self) -> Vec<HTLCUpdate> {
+               let mut ret = Vec::new();
+               mem::swap(&mut ret, &mut self.pending_htlcs_updated);
+               ret
+       }
+
        /// Can only fail if idx is < get_min_seen_secret
        pub(super) fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
                for i in 0..self.old_secrets.len() {
@@ -2402,7 +2387,7 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
        /// Eventually this should be pub and, roughly, implement ChainListener, however this requires
        /// &mut self, as well as returns new spendable outputs and outpoints to watch for spending of
        /// on-chain.
-       fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface, fee_estimator: &FeeEstimator)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>, Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)>) {
+       fn block_connected(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface, fee_estimator: &FeeEstimator)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>) {
                for tx in txn_matched {
                        let mut output_val = 0;
                        for out in tx.output.iter() {
@@ -2415,7 +2400,6 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                log_trace!(self, "Block {} at height {} connected with {} txn matched", block_hash, height, txn_matched.len());
                let mut watch_outputs = Vec::new();
                let mut spendable_outputs = Vec::new();
-               let mut htlc_updated = Vec::new();
                let mut bump_candidates = HashSet::new();
                for tx in txn_matched {
                        if tx.input.len() == 1 {
@@ -2474,10 +2458,7 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                        // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
                        // can also be resolved in a few other ways which can have more than one output. Thus,
                        // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
-                       let mut updated = self.is_resolving_htlc_output(&tx, height);
-                       if updated.len() > 0 {
-                               htlc_updated.append(&mut updated);
-                       }
+                       self.is_resolving_htlc_output(&tx, height);
 
                        // Scan all input to verify is one of the outpoint spent is of interest for us
                        let mut claimed_outputs_material = Vec::new();
@@ -2600,7 +2581,11 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                                        },
                                        OnchainEvent::HTLCUpdate { htlc_update } => {
                                                log_trace!(self, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!((htlc_update.1).0));
-                                               htlc_updated.push((htlc_update.0, None, htlc_update.1));
+                                               self.pending_htlcs_updated.push(HTLCUpdate {
+                                                       payment_hash: htlc_update.1,
+                                                       payment_preimage: None,
+                                                       source: htlc_update.0,
+                                               });
                                        },
                                        OnchainEvent::ContentiousOutpoint { outpoint, .. } => {
                                                self.claimable_outpoints.remove(&outpoint);
@@ -2632,7 +2617,7 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                for &(ref txid, ref output_scripts) in watch_outputs.iter() {
                        self.outputs_to_watch.insert(txid.clone(), output_scripts.iter().map(|o| o.script_pubkey.clone()).collect());
                }
-               (watch_outputs, spendable_outputs, htlc_updated)
+               (watch_outputs, spendable_outputs)
        }
 
        fn block_disconnected(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface, fee_estimator: &FeeEstimator) {
@@ -2752,9 +2737,7 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
 
        /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a local
        /// or remote commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
-       fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) -> Vec<(HTLCSource, Option<PaymentPreimage>, PaymentHash)> {
-               let mut htlc_updated = Vec::new();
-
+       fn is_resolving_htlc_output(&mut self, tx: &Transaction, height: u32) {
                'outer_loop: for input in &tx.input {
                        let mut payment_data = None;
                        let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
@@ -2854,10 +2837,18 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                                let mut payment_preimage = PaymentPreimage([0; 32]);
                                if accepted_preimage_claim {
                                        payment_preimage.0.copy_from_slice(&input.witness[3]);
-                                       htlc_updated.push((source, Some(payment_preimage), payment_hash));
+                                       self.pending_htlcs_updated.push(HTLCUpdate {
+                                               source,
+                                               payment_preimage: Some(payment_preimage),
+                                               payment_hash
+                                       });
                                } else if offered_preimage_claim {
                                        payment_preimage.0.copy_from_slice(&input.witness[1]);
-                                       htlc_updated.push((source, Some(payment_preimage), payment_hash));
+                                       self.pending_htlcs_updated.push(HTLCUpdate {
+                                               source,
+                                               payment_preimage: Some(payment_preimage),
+                                               payment_hash
+                                       });
                                } else {
                                        log_info!(self, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height{})", log_bytes!(payment_hash.0), height + ANTI_REORG_DELAY - 1);
                                        match self.onchain_events_waiting_threshold_conf.entry(height + ANTI_REORG_DELAY - 1) {
@@ -2880,7 +2871,6 @@ impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
                                }
                        }
                }
-               htlc_updated
        }
 
        /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize coutnerparty onchain) lays on the assumption of claim transactions getting confirmed before timelock expiration
@@ -3221,6 +3211,12 @@ impl<R: ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
                        }
                }
 
+               let pending_htlcs_updated_len: u64 = Readable::read(reader)?;
+               let mut pending_htlcs_updated = Vec::with_capacity(cmp::min(pending_htlcs_updated_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
+               for _ in 0..pending_htlcs_updated_len {
+                       pending_htlcs_updated.push(Readable::read(reader)?);
+               }
+
                let last_block_hash: Sha256dHash = Readable::read(reader)?;
                let destination_script = Readable::read(reader)?;
                let to_remote_rescue = match <u8 as Readable<R>>::read(reader)? {
@@ -3321,6 +3317,7 @@ impl<R: ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
                        current_remote_commitment_number,
 
                        payment_preimages,
+                       pending_htlcs_updated,
 
                        destination_script,
                        to_remote_rescue,