multi: update ChannelManager tx broadcaster from Arc to Deref
[rust-lightning] / lightning / src / ln / channelmonitor.rs
index 94d13a8117ae4ac91aa532c3e1b1fb80e1ed4bad..20e8a2fdabe4cbad97cd816fd2b0d35e7e8526a9 100644 (file)
@@ -35,7 +35,7 @@ use ln::chan_utils::{HTLCOutputInCommitment, LocalCommitmentTransaction, HTLCTyp
 use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
 use chain::chaininterface::{ChainListener, ChainWatchInterface, BroadcasterInterface, FeeEstimator, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
 use chain::transaction::OutPoint;
-use chain::keysinterface::SpendableOutputDescriptor;
+use chain::keysinterface::{SpendableOutputDescriptor, ChannelKeys};
 use util::logger::Logger;
 use util::ser::{ReadableArgs, Readable, Writer, Writeable, U48};
 use util::{byte_utils, events};
@@ -43,6 +43,7 @@ use util::{byte_utils, events};
 use std::collections::{HashMap, hash_map, HashSet};
 use std::sync::{Arc,Mutex};
 use std::{hash,cmp, mem};
+use std::ops::Deref;
 
 /// An error enum representing a failure to persist a channel monitor update.
 #[derive(Clone)]
@@ -93,11 +94,13 @@ 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
@@ -114,17 +117,28 @@ pub struct HTLCUpdate {
 /// than calling these methods directly, the user should register implementors as listeners to the
 /// BlockNotifier and call the BlockNotifier's `block_(dis)connected` methods, which will notify
 /// all registered listeners in one go.
-pub trait ManyChannelMonitor: Send + Sync {
+pub trait ManyChannelMonitor<ChanSigner: ChannelKeys>: Send + Sync {
        /// Adds or updates a monitor for the given `funding_txo`.
        ///
-       /// Implementor must also ensure that the funding_txo outpoint is registered with any relevant
-       /// ChainWatchInterfaces such that the provided monitor receives block_connected callbacks with
-       /// any spends of it.
-       fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr>;
+       /// Implementer must also ensure that the funding_txo txid *and* outpoint are registered with
+       /// any relevant ChainWatchInterfaces such that the provided monitor receives block_connected
+       /// callbacks with the funding transaction, or any spends of it.
+       ///
+       /// Further, the implementer must also ensure that each output returned in
+       /// monitor.get_outputs_to_watch() is registered to ensure that the provided monitor learns about
+       /// any spends of any of the outputs.
+       ///
+       /// Any spends of outputs which should have been registered which aren't passed to
+       /// ChannelMonitors via block_connected may result in funds loss.
+       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
@@ -138,29 +152,28 @@ pub trait ManyChannelMonitor: Send + Sync {
 ///
 /// If you're using this for local monitoring of your own channels, you probably want to use
 /// `OutPoint` as the key, which will give you a ManyChannelMonitor implementation.
-pub struct SimpleManyChannelMonitor<Key> {
+pub struct SimpleManyChannelMonitor<Key, ChanSigner: ChannelKeys, T: Deref> where T::Target: BroadcasterInterface {
        #[cfg(test)] // Used in ChannelManager tests to manipulate channels directly
-       pub monitors: Mutex<HashMap<Key, ChannelMonitor>>,
+       pub monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
        #[cfg(not(test))]
-       monitors: Mutex<HashMap<Key, ChannelMonitor>>,
+       monitors: Mutex<HashMap<Key, ChannelMonitor<ChanSigner>>>,
        chain_monitor: Arc<ChainWatchInterface>,
-       broadcaster: Arc<BroadcasterInterface>,
+       broadcaster: T,
        pending_events: Mutex<Vec<events::Event>>,
-       pending_htlc_updated: Mutex<HashMap<PaymentHash, Vec<(HTLCSource, Option<PaymentPreimage>)>>>,
        logger: Arc<Logger>,
        fee_estimator: Arc<FeeEstimator>
 }
 
-impl<'a, Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelMonitor<Key> {
-
+impl<'a, Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref + Sync + Send> ChainListener for SimpleManyChannelMonitor<Key, ChanSigner, T>
+       where T::Target: BroadcasterInterface
+{
        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,
@@ -172,35 +185,6 @@ impl<'a, Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelM
                                                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();
@@ -216,25 +200,26 @@ impl<'a, Key : Send + cmp::Eq + hash::Hash> ChainListener for SimpleManyChannelM
        }
 }
 
-impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key> {
+impl<Key : Send + cmp::Eq + hash::Hash + 'static, ChanSigner: ChannelKeys, T: Deref> SimpleManyChannelMonitor<Key, ChanSigner, T>
+       where T::Target: BroadcasterInterface
+{
        /// Creates a new object which can be used to monitor several channels given the chain
        /// interface with which to register to receive notifications.
-       pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: Arc<BroadcasterInterface>, logger: Arc<Logger>, feeest: Arc<FeeEstimator>) -> Arc<SimpleManyChannelMonitor<Key>> {
-               let res = Arc::new(SimpleManyChannelMonitor {
+       pub fn new(chain_monitor: Arc<ChainWatchInterface>, broadcaster: T, logger: Arc<Logger>, feeest: Arc<FeeEstimator>) -> SimpleManyChannelMonitor<Key, ChanSigner, T> {
+               let res = SimpleManyChannelMonitor {
                        monitors: Mutex::new(HashMap::new()),
                        chain_monitor,
                        broadcaster,
                        pending_events: Mutex::new(Vec::new()),
-                       pending_htlc_updated: Mutex::new(HashMap::new()),
                        logger,
                        fee_estimator: feeest,
-               });
+               };
 
                res
        }
 
        /// Adds or updates the monitor which monitors the channel referred to by the given key.
-       pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor) -> Result<(), MonitorUpdateError> {
+       pub fn add_update_monitor_by_key(&self, key: Key, monitor: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
                let mut monitors = self.monitors.lock().unwrap();
                match monitors.get_mut(&key) {
                        Some(orig_monitor) => {
@@ -260,36 +245,38 @@ impl<Key : Send + cmp::Eq + hash::Hash + 'static> SimpleManyChannelMonitor<Key>
                                self.chain_monitor.watch_all_txn();
                        }
                }
+               for (txid, outputs) in monitor.get_outputs_to_watch().iter() {
+                       for (idx, script) in outputs.iter().enumerate() {
+                               self.chain_monitor.install_watch_outpoint((*txid, idx as u32), script);
+                       }
+               }
                monitors.insert(key, monitor);
                Ok(())
        }
 }
 
-impl ManyChannelMonitor for SimpleManyChannelMonitor<OutPoint> {
-       fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor) -> Result<(), ChannelMonitorUpdateErr> {
+impl<ChanSigner: ChannelKeys, T: Deref + Sync + Send> ManyChannelMonitor<ChanSigner> for SimpleManyChannelMonitor<OutPoint, ChanSigner, T>
+       where T::Target: BroadcasterInterface
+{
+       fn add_update_monitor(&self, funding_txo: OutPoint, monitor: ChannelMonitor<ChanSigner>) -> Result<(), ChannelMonitorUpdateErr> {
                match self.add_update_monitor_by_key(funding_txo, monitor) {
                        Ok(_) => Ok(()),
                        Err(_) => Err(ChannelMonitorUpdateErr::PermanentFailure),
                }
        }
 
-       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
        }
 }
 
-impl<Key : Send + cmp::Eq + hash::Hash> events::EventsProvider for SimpleManyChannelMonitor<Key> {
+impl<Key : Send + cmp::Eq + hash::Hash, ChanSigner: ChannelKeys, T: Deref> events::EventsProvider for SimpleManyChannelMonitor<Key, ChanSigner, T>
+       where T::Target: BroadcasterInterface
+{
        fn get_and_clear_pending_events(&self) -> Vec<events::Event> {
                let mut pending_events = self.pending_events.lock().unwrap();
                let mut ret = Vec::new();
@@ -327,9 +314,10 @@ pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
 /// keeping bumping another claim tx to solve the outpoint.
 pub(crate) const ANTI_REORG_DELAY: u32 = 6;
 
-#[derive(Clone, PartialEq)]
-enum Storage {
+#[derive(Clone)]
+enum Storage<ChanSigner: ChannelKeys> {
        Local {
+               keys: ChanSigner,
                funding_key: SecretKey,
                revocation_base_key: SecretKey,
                htlc_base_key: SecretKey,
@@ -346,6 +334,29 @@ enum Storage {
        }
 }
 
+#[cfg(any(test, feature = "fuzztarget"))]
+impl<ChanSigner: ChannelKeys> PartialEq for Storage<ChanSigner> {
+       fn eq(&self, other: &Self) -> bool {
+               match *self {
+                       Storage::Local { ref keys, .. } => {
+                               let k = keys;
+                               match *other {
+                                       Storage::Local { ref keys, .. } => keys.pubkeys() == k.pubkeys(),
+                                       Storage::Watchtower { .. } => false,
+                               }
+                       },
+                       Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} => {
+                               let (rbk, hbk) = (revocation_base_key, htlc_base_key);
+                               match *other {
+                                       Storage::Local { .. } => false,
+                                       Storage::Watchtower {ref revocation_base_key, ref htlc_base_key} =>
+                                               revocation_base_key == rbk && htlc_base_key == hbk,
+                               }
+                       },
+               }
+       }
+}
+
 #[derive(Clone, PartialEq)]
 struct LocalSignedTx {
        /// txid of the transaction in tx, just used to make comparison faster
@@ -564,10 +575,10 @@ const MIN_SERIALIZATION_VERSION: u8 = 1;
 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
 /// information and are actively monitoring the chain.
 #[derive(Clone)]
-pub struct ChannelMonitor {
+pub struct ChannelMonitor<ChanSigner: ChannelKeys> {
        commitment_transaction_number_obscure_factor: u64,
 
-       key_storage: Storage,
+       key_storage: Storage<ChanSigner>,
        their_htlc_base_key: Option<PublicKey>,
        their_delayed_payment_base_key: Option<PublicKey>,
        funding_redeemscript: Option<Script>,
@@ -605,6 +616,8 @@ pub struct ChannelMonitor {
 
        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
@@ -643,6 +656,12 @@ pub struct ChannelMonitor {
        // actions when we receive a block with given height. Actions depend on OnchainEvent type.
        onchain_events_waiting_threshold_conf: HashMap<u32, Vec<OnchainEvent>>,
 
+       // If we get serialized out and re-read, we need to make sure that the chain monitoring
+       // interface knows about the TXOs that we want to be notified of spends of. We could probably
+       // be smart and derive them from the above storage fields, but its much simpler and more
+       // Obviously Correct (tm) if we just keep track of them explicitly.
+       outputs_to_watch: HashMap<Sha256dHash, Vec<Script>>,
+
        // We simply modify last_block_hash in Channel's block_connected so that serialization is
        // consistent but hopefully the users' copy handles block_connected in a consistent way.
        // (we do *not*, however, update them in insert_combine to ensure any local user copies keep
@@ -691,7 +710,7 @@ macro_rules! subtract_high_prio_fee {
 #[cfg(any(test, feature = "fuzztarget"))]
 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
 /// underlying object
-impl PartialEq for ChannelMonitor {
+impl<ChanSigner: ChannelKeys> PartialEq for ChannelMonitor<ChanSigner> {
        fn eq(&self, other: &Self) -> bool {
                if self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
                        self.key_storage != other.key_storage ||
@@ -709,11 +728,13 @@ impl PartialEq for ChannelMonitor {
                        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 ||
                        self.claimable_outpoints != other.claimable_outpoints ||
-                       self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf
+                       self.onchain_events_waiting_threshold_conf != other.onchain_events_waiting_threshold_conf ||
+                       self.outputs_to_watch != other.outputs_to_watch
                {
                        false
                } else {
@@ -727,12 +748,269 @@ impl PartialEq for ChannelMonitor {
        }
 }
 
-impl ChannelMonitor {
-       pub(super) fn new(funding_key: &SecretKey, revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, shutdown_pubkey: &PublicKey, our_to_self_delay: u16, destination_script: Script, logger: Arc<Logger>) -> ChannelMonitor {
+impl<ChanSigner: ChannelKeys + Writeable> ChannelMonitor<ChanSigner> {
+       /// Serializes into a vec, with various modes for the exposed pub fns
+       fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
+               //TODO: We still write out all the serialization here manually instead of using the fancy
+               //serialization framework we have, we should migrate things over to it.
+               writer.write_all(&[SERIALIZATION_VERSION; 1])?;
+               writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
+
+               // Set in initial Channel-object creation, so should always be set by now:
+               U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
+
+               macro_rules! write_option {
+                       ($thing: expr) => {
+                               match $thing {
+                                       &Some(ref t) => {
+                                               1u8.write(writer)?;
+                                               t.write(writer)?;
+                                       },
+                                       &None => 0u8.write(writer)?,
+                               }
+                       }
+               }
+
+               match self.key_storage {
+                       Storage::Local { ref keys, ref funding_key, ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref funding_info, ref current_remote_commitment_txid, ref prev_remote_commitment_txid } => {
+                               writer.write_all(&[0; 1])?;
+                               keys.write(writer)?;
+                               writer.write_all(&funding_key[..])?;
+                               writer.write_all(&revocation_base_key[..])?;
+                               writer.write_all(&htlc_base_key[..])?;
+                               writer.write_all(&delayed_payment_base_key[..])?;
+                               writer.write_all(&payment_base_key[..])?;
+                               writer.write_all(&shutdown_pubkey.serialize())?;
+                               match funding_info  {
+                                       &Some((ref outpoint, ref script)) => {
+                                               writer.write_all(&outpoint.txid[..])?;
+                                               writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
+                                               script.write(writer)?;
+                                       },
+                                       &None => {
+                                               debug_assert!(false, "Try to serialize a useless Local monitor !");
+                                       },
+                               }
+                               current_remote_commitment_txid.write(writer)?;
+                               prev_remote_commitment_txid.write(writer)?;
+                       },
+                       Storage::Watchtower { .. } => unimplemented!(),
+               }
+
+               writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
+               writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
+               self.funding_redeemscript.as_ref().unwrap().write(writer)?;
+               self.channel_value_satoshis.unwrap().write(writer)?;
+
+               match self.their_cur_revocation_points {
+                       Some((idx, pubkey, second_option)) => {
+                               writer.write_all(&byte_utils::be48_to_array(idx))?;
+                               writer.write_all(&pubkey.serialize())?;
+                               match second_option {
+                                       Some(second_pubkey) => {
+                                               writer.write_all(&second_pubkey.serialize())?;
+                                       },
+                                       None => {
+                                               writer.write_all(&[0; 33])?;
+                                       },
+                               }
+                       },
+                       None => {
+                               writer.write_all(&byte_utils::be48_to_array(0))?;
+                       },
+               }
+
+               writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
+               writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
+
+               for &(ref secret, ref idx) in self.old_secrets.iter() {
+                       writer.write_all(secret)?;
+                       writer.write_all(&byte_utils::be64_to_array(*idx))?;
+               }
+
+               macro_rules! serialize_htlc_in_commitment {
+                       ($htlc_output: expr) => {
+                               writer.write_all(&[$htlc_output.offered as u8; 1])?;
+                               writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
+                               writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
+                               writer.write_all(&$htlc_output.payment_hash.0[..])?;
+                               $htlc_output.transaction_output_index.write(writer)?;
+                       }
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
+               for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
+                       writer.write_all(&txid[..])?;
+                       writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
+                       for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
+                               serialize_htlc_in_commitment!(htlc_output);
+                               write_option!(htlc_source);
+                       }
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
+               for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
+                       writer.write_all(&txid[..])?;
+                       writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
+                       (txouts.len() as u64).write(writer)?;
+                       for script in txouts.iter() {
+                               script.write(writer)?;
+                       }
+               }
+
+               if for_local_storage {
+                       writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
+                       for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
+                               writer.write_all(&payment_hash.0[..])?;
+                               writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
+                       }
+               } else {
+                       writer.write_all(&byte_utils::be64_to_array(0))?;
+               }
+
+               macro_rules! serialize_local_tx {
+                       ($local_tx: expr) => {
+                               $local_tx.tx.write(writer)?;
+                               writer.write_all(&$local_tx.revocation_key.serialize())?;
+                               writer.write_all(&$local_tx.a_htlc_key.serialize())?;
+                               writer.write_all(&$local_tx.b_htlc_key.serialize())?;
+                               writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
+                               writer.write_all(&$local_tx.per_commitment_point.serialize())?;
+
+                               writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
+                               writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
+                               for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
+                                       serialize_htlc_in_commitment!(htlc_output);
+                                       if let &Some(ref their_sig) = sig {
+                                               1u8.write(writer)?;
+                                               writer.write_all(&their_sig.serialize_compact())?;
+                                       } else {
+                                               0u8.write(writer)?;
+                                       }
+                                       write_option!(htlc_source);
+                               }
+                       }
+               }
+
+               if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
+                       writer.write_all(&[1; 1])?;
+                       serialize_local_tx!(prev_local_tx);
+               } else {
+                       writer.write_all(&[0; 1])?;
+               }
+
+               if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
+                       writer.write_all(&[1; 1])?;
+                       serialize_local_tx!(cur_local_tx);
+               } else {
+                       writer.write_all(&[0; 1])?;
+               }
+
+               if for_local_storage {
+                       writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
+               } else {
+                       writer.write_all(&byte_utils::be48_to_array(0))?;
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
+               for payment_preimage in self.payment_preimages.values() {
+                       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 {
+                       writer.write_all(&[1; 1])?;
+                       to_remote_script.write(writer)?;
+                       local_key.write(writer)?;
+               } else {
+                       writer.write_all(&[0; 1])?;
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
+               for (ref ancestor_claim_txid, claim_tx_data) in self.pending_claim_requests.iter() {
+                       ancestor_claim_txid.write(writer)?;
+                       claim_tx_data.write(writer)?;
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.claimable_outpoints.len() as u64))?;
+               for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
+                       outp.write(writer)?;
+                       claim_and_height.0.write(writer)?;
+                       claim_and_height.1.write(writer)?;
+               }
+
+               writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
+               for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
+                       writer.write_all(&byte_utils::be32_to_array(**target))?;
+                       writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
+                       for ev in events.iter() {
+                               match *ev {
+                                       OnchainEvent::Claim { ref claim_request } => {
+                                               writer.write_all(&[0; 1])?;
+                                               claim_request.write(writer)?;
+                                       },
+                                       OnchainEvent::HTLCUpdate { ref htlc_update } => {
+                                               writer.write_all(&[1; 1])?;
+                                               htlc_update.0.write(writer)?;
+                                               htlc_update.1.write(writer)?;
+                                       },
+                                       OnchainEvent::ContentiousOutpoint { ref outpoint, ref input_material } => {
+                                               writer.write_all(&[2; 1])?;
+                                               outpoint.write(writer)?;
+                                               input_material.write(writer)?;
+                                       }
+                               }
+                       }
+               }
+
+               (self.outputs_to_watch.len() as u64).write(writer)?;
+               for (txid, output_scripts) in self.outputs_to_watch.iter() {
+                       txid.write(writer)?;
+                       (output_scripts.len() as u64).write(writer)?;
+                       for script in output_scripts.iter() {
+                               script.write(writer)?;
+                       }
+               }
+
+               Ok(())
+       }
+
+       /// Writes this monitor into the given writer, suitable for writing to disk.
+       ///
+       /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
+       /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
+       /// the "reorg path" (ie not just starting at the same height but starting at the highest
+       /// common block that appears on your best chain as well as on the chain which contains the
+       /// last block hash returned) upon deserializing the object!
+       pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+               self.write(writer, true)
+       }
+
+       /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
+       ///
+       /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
+       /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
+       /// the "reorg path" (ie not just starting at the same height but starting at the highest
+       /// common block that appears on your best chain as well as on the chain which contains the
+       /// last block hash returned) upon deserializing the object!
+       pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+               self.write(writer, false)
+       }
+}
+
+impl<ChanSigner: ChannelKeys> ChannelMonitor<ChanSigner> {
+       pub(super) fn new(keys: ChanSigner, funding_key: &SecretKey, revocation_base_key: &SecretKey, delayed_payment_base_key: &SecretKey, htlc_base_key: &SecretKey, payment_base_key: &SecretKey, shutdown_pubkey: &PublicKey, our_to_self_delay: u16, destination_script: Script, logger: Arc<Logger>) -> ChannelMonitor<ChanSigner> {
                ChannelMonitor {
                        commitment_transaction_number_obscure_factor: 0,
 
                        key_storage: Storage::Local {
+                               keys,
                                funding_key: funding_key.clone(),
                                revocation_base_key: revocation_base_key.clone(),
                                htlc_base_key: htlc_base_key.clone(),
@@ -762,6 +1040,8 @@ impl ChannelMonitor {
                        current_remote_commitment_number: 1 << 48,
 
                        payment_preimages: HashMap::new(),
+                       pending_htlcs_updated: Vec::new(),
+
                        destination_script: destination_script,
                        to_remote_rescue: None,
 
@@ -770,6 +1050,7 @@ impl ChannelMonitor {
                        claimable_outpoints: HashMap::new(),
 
                        onchain_events_waiting_threshold_conf: HashMap::new(),
+                       outputs_to_watch: HashMap::new(),
 
                        last_block_hash: Default::default(),
                        secp_ctx: Secp256k1::new(),
@@ -843,10 +1124,10 @@ impl ChannelMonitor {
        /// needed by local commitment transactions HTCLs nor by remote ones. Unless we haven't already seen remote
        /// commitment transaction's secret, they are de facto pruned (we can use revocation key).
        pub(super) fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
-               let pos = ChannelMonitor::place_secret(idx);
+               let pos = ChannelMonitor::<ChanSigner>::place_secret(idx);
                for i in 0..pos {
                        let (old_secret, old_idx) = self.old_secrets[i as usize];
-                       if ChannelMonitor::derive_secret(secret, pos, old_idx) != old_secret {
+                       if ChannelMonitor::<ChanSigner>::derive_secret(secret, pos, old_idx) != old_secret {
                                return Err(MonitorUpdateError("Previous secret did not match new one"));
                        }
                }
@@ -946,8 +1227,8 @@ impl ChannelMonitor {
 
        pub(super) fn provide_rescue_remote_commitment_tx_info(&mut self, their_revocation_point: PublicKey) {
                match self.key_storage {
-                       Storage::Local { ref payment_base_key, .. } => {
-                               if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &payment_base_key)) {
+                       Storage::Local { ref payment_base_key, ref keys, .. } => {
+                               if let Ok(payment_key) = chan_utils::derive_public_key(&self.secp_ctx, &their_revocation_point, &keys.pubkeys().payment_basepoint) {
                                        let to_remote_script =  Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0)
                                                .push_slice(&Hash160::hash(&payment_key.serialize())[..])
                                                .into_script();
@@ -990,7 +1271,7 @@ impl ChannelMonitor {
        /// Combines this ChannelMonitor with the information contained in the other ChannelMonitor.
        /// After a successful call this ChannelMonitor is up-to-date and is safe to use to monitor the
        /// chain for new blocks/transactions.
-       pub fn insert_combine(&mut self, mut other: ChannelMonitor) -> Result<(), MonitorUpdateError> {
+       pub fn insert_combine(&mut self, mut other: ChannelMonitor<ChanSigner>) -> Result<(), MonitorUpdateError> {
                match self.key_storage {
                        Storage::Local { ref funding_info, .. } => {
                                if funding_info.is_none() { return Err(MonitorUpdateError("Try to combine a Local monitor without funding_info")); }
@@ -1009,359 +1290,134 @@ impl ChannelMonitor {
                        Storage::Watchtower { .. } => {
                                if let Storage::Watchtower { .. } = other.key_storage {
                                        unimplemented!();
-                               } else {
-                                       return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
-                               }
-                       },
-               }
-               let other_min_secret = other.get_min_seen_secret();
-               let our_min_secret = self.get_min_seen_secret();
-               if our_min_secret > other_min_secret {
-                       self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
-               }
-               if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
-                       if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
-                               let our_commitment_number = 0xffffffffffff - ((((local_tx.tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
-                               let other_commitment_number = 0xffffffffffff - ((((other_local_tx.tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (other_local_tx.tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ other.commitment_transaction_number_obscure_factor);
-                               if our_commitment_number >= other_commitment_number {
-                                       self.key_storage = other.key_storage;
-                               }
-                       }
-               }
-               // TODO: We should use current_remote_commitment_number and the commitment number out of
-               // local transactions to decide how to merge
-               if our_min_secret >= other_min_secret {
-                       self.their_cur_revocation_points = other.their_cur_revocation_points;
-                       for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
-                               self.remote_claimable_outpoints.insert(txid, htlcs);
-                       }
-                       if let Some(local_tx) = other.prev_local_signed_commitment_tx {
-                               self.prev_local_signed_commitment_tx = Some(local_tx);
-                       }
-                       if let Some(local_tx) = other.current_local_signed_commitment_tx {
-                               self.current_local_signed_commitment_tx = Some(local_tx);
-                       }
-                       self.payment_preimages = other.payment_preimages;
-                       self.to_remote_rescue = other.to_remote_rescue;
-               }
-
-               self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
-               Ok(())
-       }
-
-       /// Allows this monitor to scan only for transactions which are applicable. Note that this is
-       /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
-       /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
-       /// provides slightly better privacy.
-       /// It's the responsibility of the caller to register outpoint and script with passing the former
-       /// value as key to add_update_monitor.
-       pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
-               match self.key_storage {
-                       Storage::Local { ref mut funding_info, .. } => {
-                               *funding_info = Some(new_funding_info);
-                       },
-                       Storage::Watchtower { .. } => {
-                               panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
-                       }
-               }
-       }
-
-       /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
-       /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
-       pub(super) fn set_basic_channel_info(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey, their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64, commitment_transaction_number_obscure_factor: u64) {
-               self.their_htlc_base_key = Some(their_htlc_base_key.clone());
-               self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
-               self.their_to_self_delay = Some(their_to_self_delay);
-               self.funding_redeemscript = Some(funding_redeemscript);
-               self.channel_value_satoshis = Some(channel_value_satoshis);
-               assert!(commitment_transaction_number_obscure_factor < (1 << 48));
-               self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
-       }
-
-       pub(super) fn unset_funding_info(&mut self) {
-               match self.key_storage {
-                       Storage::Local { ref mut funding_info, .. } => {
-                               *funding_info = None;
-                       },
-                       Storage::Watchtower { .. } => {
-                               panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
-                       },
-               }
-       }
-
-       /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
-       pub fn get_funding_txo(&self) -> Option<OutPoint> {
-               match self.key_storage {
-                       Storage::Local { ref funding_info, .. } => {
-                               match funding_info {
-                                       &Some((outpoint, _)) => Some(outpoint),
-                                       &None => None
-                               }
-                       },
-                       Storage::Watchtower { .. } => {
-                               return None;
-                       }
-               }
-       }
-
-       /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
-       /// Generally useful when deserializing as during normal operation the return values of
-       /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
-       /// that the get_funding_txo outpoint and transaction must also be monitored for!).
-       pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
-               let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
-               for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
-                       for (idx, output) in outputs.iter().enumerate() {
-                               res.push(((*txid).clone(), idx as u32, output));
-                       }
-               }
-               res
-       }
-
-       /// Serializes into a vec, with various modes for the exposed pub fns
-       fn write<W: Writer>(&self, writer: &mut W, for_local_storage: bool) -> Result<(), ::std::io::Error> {
-               //TODO: We still write out all the serialization here manually instead of using the fancy
-               //serialization framework we have, we should migrate things over to it.
-               writer.write_all(&[SERIALIZATION_VERSION; 1])?;
-               writer.write_all(&[MIN_SERIALIZATION_VERSION; 1])?;
-
-               // Set in initial Channel-object creation, so should always be set by now:
-               U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
-
-               macro_rules! write_option {
-                       ($thing: expr) => {
-                               match $thing {
-                                       &Some(ref t) => {
-                                               1u8.write(writer)?;
-                                               t.write(writer)?;
-                                       },
-                                       &None => 0u8.write(writer)?,
-                               }
-                       }
-               }
-
-               match self.key_storage {
-                       Storage::Local { ref funding_key, ref revocation_base_key, ref htlc_base_key, ref delayed_payment_base_key, ref payment_base_key, ref shutdown_pubkey, ref funding_info, ref current_remote_commitment_txid, ref prev_remote_commitment_txid } => {
-                               writer.write_all(&[0; 1])?;
-                               writer.write_all(&funding_key[..])?;
-                               writer.write_all(&revocation_base_key[..])?;
-                               writer.write_all(&htlc_base_key[..])?;
-                               writer.write_all(&delayed_payment_base_key[..])?;
-                               writer.write_all(&payment_base_key[..])?;
-                               writer.write_all(&shutdown_pubkey.serialize())?;
-                               match funding_info  {
-                                       &Some((ref outpoint, ref script)) => {
-                                               writer.write_all(&outpoint.txid[..])?;
-                                               writer.write_all(&byte_utils::be16_to_array(outpoint.index))?;
-                                               script.write(writer)?;
-                                       },
-                                       &None => {
-                                               debug_assert!(false, "Try to serialize a useless Local monitor !");
-                                       },
-                               }
-                               current_remote_commitment_txid.write(writer)?;
-                               prev_remote_commitment_txid.write(writer)?;
-                       },
-                       Storage::Watchtower { .. } => unimplemented!(),
-               }
-
-               writer.write_all(&self.their_htlc_base_key.as_ref().unwrap().serialize())?;
-               writer.write_all(&self.their_delayed_payment_base_key.as_ref().unwrap().serialize())?;
-               self.funding_redeemscript.as_ref().unwrap().write(writer)?;
-               self.channel_value_satoshis.unwrap().write(writer)?;
-
-               match self.their_cur_revocation_points {
-                       Some((idx, pubkey, second_option)) => {
-                               writer.write_all(&byte_utils::be48_to_array(idx))?;
-                               writer.write_all(&pubkey.serialize())?;
-                               match second_option {
-                                       Some(second_pubkey) => {
-                                               writer.write_all(&second_pubkey.serialize())?;
-                                       },
-                                       None => {
-                                               writer.write_all(&[0; 33])?;
-                                       },
+                               } else {
+                                       return Err(MonitorUpdateError("Try to combine a Watchtower monitor with a Local one !"));
                                }
                        },
-                       None => {
-                               writer.write_all(&byte_utils::be48_to_array(0))?;
-                       },
                }
-
-               writer.write_all(&byte_utils::be16_to_array(self.our_to_self_delay))?;
-               writer.write_all(&byte_utils::be16_to_array(self.their_to_self_delay.unwrap()))?;
-
-               for &(ref secret, ref idx) in self.old_secrets.iter() {
-                       writer.write_all(secret)?;
-                       writer.write_all(&byte_utils::be64_to_array(*idx))?;
+               let other_min_secret = other.get_min_seen_secret();
+               let our_min_secret = self.get_min_seen_secret();
+               if our_min_secret > other_min_secret {
+                       self.provide_secret(other_min_secret, other.get_secret(other_min_secret).unwrap())?;
                }
-
-               macro_rules! serialize_htlc_in_commitment {
-                       ($htlc_output: expr) => {
-                               writer.write_all(&[$htlc_output.offered as u8; 1])?;
-                               writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
-                               writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
-                               writer.write_all(&$htlc_output.payment_hash.0[..])?;
-                               $htlc_output.transaction_output_index.write(writer)?;
+               if let Some(ref local_tx) = self.current_local_signed_commitment_tx {
+                       if let Some(ref other_local_tx) = other.current_local_signed_commitment_tx {
+                               let our_commitment_number = 0xffffffffffff - ((((local_tx.tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (local_tx.tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
+                               let other_commitment_number = 0xffffffffffff - ((((other_local_tx.tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (other_local_tx.tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ other.commitment_transaction_number_obscure_factor);
+                               if our_commitment_number >= other_commitment_number {
+                                       self.key_storage = other.key_storage;
+                               }
                        }
                }
-
-               writer.write_all(&byte_utils::be64_to_array(self.remote_claimable_outpoints.len() as u64))?;
-               for (ref txid, ref htlc_infos) in self.remote_claimable_outpoints.iter() {
-                       writer.write_all(&txid[..])?;
-                       writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
-                       for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
-                               serialize_htlc_in_commitment!(htlc_output);
-                               write_option!(htlc_source);
+               // TODO: We should use current_remote_commitment_number and the commitment number out of
+               // local transactions to decide how to merge
+               if our_min_secret >= other_min_secret {
+                       self.their_cur_revocation_points = other.their_cur_revocation_points;
+                       for (txid, htlcs) in other.remote_claimable_outpoints.drain() {
+                               self.remote_claimable_outpoints.insert(txid, htlcs);
                        }
-               }
-
-               writer.write_all(&byte_utils::be64_to_array(self.remote_commitment_txn_on_chain.len() as u64))?;
-               for (ref txid, &(commitment_number, ref txouts)) in self.remote_commitment_txn_on_chain.iter() {
-                       writer.write_all(&txid[..])?;
-                       writer.write_all(&byte_utils::be48_to_array(commitment_number))?;
-                       (txouts.len() as u64).write(writer)?;
-                       for script in txouts.iter() {
-                               script.write(writer)?;
+                       if let Some(local_tx) = other.prev_local_signed_commitment_tx {
+                               self.prev_local_signed_commitment_tx = Some(local_tx);
                        }
-               }
-
-               if for_local_storage {
-                       writer.write_all(&byte_utils::be64_to_array(self.remote_hash_commitment_number.len() as u64))?;
-                       for (ref payment_hash, commitment_number) in self.remote_hash_commitment_number.iter() {
-                               writer.write_all(&payment_hash.0[..])?;
-                               writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
+                       if let Some(local_tx) = other.current_local_signed_commitment_tx {
+                               self.current_local_signed_commitment_tx = Some(local_tx);
                        }
-               } else {
-                       writer.write_all(&byte_utils::be64_to_array(0))?;
+                       self.payment_preimages = other.payment_preimages;
+                       self.to_remote_rescue = other.to_remote_rescue;
                }
 
-               macro_rules! serialize_local_tx {
-                       ($local_tx: expr) => {
-                               $local_tx.tx.write(writer)?;
-                               writer.write_all(&$local_tx.revocation_key.serialize())?;
-                               writer.write_all(&$local_tx.a_htlc_key.serialize())?;
-                               writer.write_all(&$local_tx.b_htlc_key.serialize())?;
-                               writer.write_all(&$local_tx.delayed_payment_key.serialize())?;
-                               writer.write_all(&$local_tx.per_commitment_point.serialize())?;
+               self.current_remote_commitment_number = cmp::min(self.current_remote_commitment_number, other.current_remote_commitment_number);
+               Ok(())
+       }
 
-                               writer.write_all(&byte_utils::be64_to_array($local_tx.feerate_per_kw))?;
-                               writer.write_all(&byte_utils::be64_to_array($local_tx.htlc_outputs.len() as u64))?;
-                               for &(ref htlc_output, ref sig, ref htlc_source) in $local_tx.htlc_outputs.iter() {
-                                       serialize_htlc_in_commitment!(htlc_output);
-                                       if let &Some(ref their_sig) = sig {
-                                               1u8.write(writer)?;
-                                               writer.write_all(&their_sig.serialize_compact())?;
-                                       } else {
-                                               0u8.write(writer)?;
-                                       }
-                                       write_option!(htlc_source);
-                               }
+       /// Allows this monitor to scan only for transactions which are applicable. Note that this is
+       /// optional, without it this monitor cannot be used in an SPV client, but you may wish to
+       /// avoid this (or call unset_funding_info) on a monitor you wish to send to a watchtower as it
+       /// provides slightly better privacy.
+       /// It's the responsibility of the caller to register outpoint and script with passing the former
+       /// value as key to add_update_monitor.
+       pub(super) fn set_funding_info(&mut self, new_funding_info: (OutPoint, Script)) {
+               match self.key_storage {
+                       Storage::Local { ref mut funding_info, .. } => {
+                               *funding_info = Some(new_funding_info);
+                       },
+                       Storage::Watchtower { .. } => {
+                               panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
                        }
                }
+       }
 
-               if let Some(ref prev_local_tx) = self.prev_local_signed_commitment_tx {
-                       writer.write_all(&[1; 1])?;
-                       serialize_local_tx!(prev_local_tx);
-               } else {
-                       writer.write_all(&[0; 1])?;
-               }
-
-               if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
-                       writer.write_all(&[1; 1])?;
-                       serialize_local_tx!(cur_local_tx);
-               } else {
-                       writer.write_all(&[0; 1])?;
-               }
-
-               if for_local_storage {
-                       writer.write_all(&byte_utils::be48_to_array(self.current_remote_commitment_number))?;
-               } else {
-                       writer.write_all(&byte_utils::be48_to_array(0))?;
-               }
-
-               writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
-               for payment_preimage in self.payment_preimages.values() {
-                       writer.write_all(&payment_preimage.0[..])?;
-               }
-
-               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 {
-                       writer.write_all(&[1; 1])?;
-                       to_remote_script.write(writer)?;
-                       local_key.write(writer)?;
-               } else {
-                       writer.write_all(&[0; 1])?;
-               }
-
-               writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
-               for (ref ancestor_claim_txid, claim_tx_data) in self.pending_claim_requests.iter() {
-                       ancestor_claim_txid.write(writer)?;
-                       claim_tx_data.write(writer)?;
-               }
+       /// We log these base keys at channel opening to being able to rebuild redeemscript in case of leaked revoked commit tx
+       /// Panics if commitment_transaction_number_obscure_factor doesn't fit in 48 bits
+       pub(super) fn set_basic_channel_info(&mut self, their_htlc_base_key: &PublicKey, their_delayed_payment_base_key: &PublicKey, their_to_self_delay: u16, funding_redeemscript: Script, channel_value_satoshis: u64, commitment_transaction_number_obscure_factor: u64) {
+               self.their_htlc_base_key = Some(their_htlc_base_key.clone());
+               self.their_delayed_payment_base_key = Some(their_delayed_payment_base_key.clone());
+               self.their_to_self_delay = Some(their_to_self_delay);
+               self.funding_redeemscript = Some(funding_redeemscript);
+               self.channel_value_satoshis = Some(channel_value_satoshis);
+               assert!(commitment_transaction_number_obscure_factor < (1 << 48));
+               self.commitment_transaction_number_obscure_factor = commitment_transaction_number_obscure_factor;
+       }
 
-               writer.write_all(&byte_utils::be64_to_array(self.claimable_outpoints.len() as u64))?;
-               for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
-                       outp.write(writer)?;
-                       claim_and_height.0.write(writer)?;
-                       claim_and_height.1.write(writer)?;
+       pub(super) fn unset_funding_info(&mut self) {
+               match self.key_storage {
+                       Storage::Local { ref mut funding_info, .. } => {
+                               *funding_info = None;
+                       },
+                       Storage::Watchtower { .. } => {
+                               panic!("Channel somehow ended up with its internal ChannelMonitor being in Watchtower mode?");
+                       },
                }
+       }
 
-               writer.write_all(&byte_utils::be64_to_array(self.onchain_events_waiting_threshold_conf.len() as u64))?;
-               for (ref target, ref events) in self.onchain_events_waiting_threshold_conf.iter() {
-                       writer.write_all(&byte_utils::be32_to_array(**target))?;
-                       writer.write_all(&byte_utils::be64_to_array(events.len() as u64))?;
-                       for ev in events.iter() {
-                               match *ev {
-                                       OnchainEvent::Claim { ref claim_request } => {
-                                               writer.write_all(&[0; 1])?;
-                                               claim_request.write(writer)?;
-                                       },
-                                       OnchainEvent::HTLCUpdate { ref htlc_update } => {
-                                               writer.write_all(&[1; 1])?;
-                                               htlc_update.0.write(writer)?;
-                                               htlc_update.1.write(writer)?;
-                                       },
-                                       OnchainEvent::ContentiousOutpoint { ref outpoint, ref input_material } => {
-                                               writer.write_all(&[2; 1])?;
-                                               outpoint.write(writer)?;
-                                               input_material.write(writer)?;
-                                       }
+       /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
+       pub fn get_funding_txo(&self) -> Option<OutPoint> {
+               match self.key_storage {
+                       Storage::Local { ref funding_info, .. } => {
+                               match funding_info {
+                                       &Some((outpoint, _)) => Some(outpoint),
+                                       &None => None
                                }
+                       },
+                       Storage::Watchtower { .. } => {
+                               return None;
                        }
                }
+       }
 
-               Ok(())
+       /// Gets a list of txids, with their output scripts (in the order they appear in the
+       /// transaction), which we must learn about spends of via block_connected().
+       pub fn get_outputs_to_watch(&self) -> &HashMap<Sha256dHash, Vec<Script>> {
+               &self.outputs_to_watch
        }
 
-       /// Writes this monitor into the given writer, suitable for writing to disk.
-       ///
-       /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
-       /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
-       /// the "reorg path" (ie not just starting at the same height but starting at the highest
-       /// common block that appears on your best chain as well as on the chain which contains the
-       /// last block hash returned) upon deserializing the object!
-       pub fn write_for_disk<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
-               self.write(writer, true)
+       /// Gets the sets of all outpoints which this ChannelMonitor expects to hear about spends of.
+       /// Generally useful when deserializing as during normal operation the return values of
+       /// block_connected are sufficient to ensure all relevant outpoints are being monitored (note
+       /// that the get_funding_txo outpoint and transaction must also be monitored for!).
+       pub fn get_monitored_outpoints(&self) -> Vec<(Sha256dHash, u32, &Script)> {
+               let mut res = Vec::with_capacity(self.remote_commitment_txn_on_chain.len() * 2);
+               for (ref txid, &(_, ref outputs)) in self.remote_commitment_txn_on_chain.iter() {
+                       for (idx, output) in outputs.iter().enumerate() {
+                               res.push(((*txid).clone(), idx as u32, output));
+                       }
+               }
+               res
        }
 
-       /// Encodes this monitor into the given writer, suitable for sending to a remote watchtower
-       ///
-       /// Note that the deserializer is only implemented for (Sha256dHash, ChannelMonitor), which
-       /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
-       /// the "reorg path" (ie not just starting at the same height but starting at the highest
-       /// common block that appears on your best chain as well as on the chain which contains the
-       /// last block hash returned) upon deserializing the object!
-       pub fn write_for_watchtower<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
-               self.write(writer, false)
+       /// 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() {
                        if (idx & (!((1 << i) - 1))) == self.old_secrets[i].1 {
-                               return Some(ChannelMonitor::derive_secret(self.old_secrets[i].0, i as u8, idx))
+                               return Some(ChannelMonitor::<ChanSigner>::derive_secret(self.old_secrets[i].0, i as u8, idx))
                        }
                }
                assert!(idx < self.get_min_seen_secret());
@@ -1419,10 +1475,10 @@ impl ChannelMonitor {
                        let secret = self.get_secret(commitment_number).unwrap();
                        let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
                        let (revocation_pubkey, b_htlc_key, local_payment_key) = match self.key_storage {
-                               Storage::Local { ref revocation_base_key, ref htlc_base_key, ref payment_base_key, .. } => {
+                               Storage::Local { ref keys, ref payment_base_key, .. } => {
                                        let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
-                                       (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
-                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))),
+                                       (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint)),
+                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().htlc_basepoint)),
                                        Some(ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, &per_commitment_point, &payment_base_key))))
                                },
                                Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
@@ -1734,9 +1790,9 @@ impl ChannelMonitor {
                                        } else { None };
                                if let Some(revocation_point) = revocation_point_option {
                                        let (revocation_pubkey, b_htlc_key) = match self.key_storage {
-                                               Storage::Local { ref revocation_base_key, ref htlc_base_key, .. } => {
-                                                       (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key))),
-                                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &PublicKey::from_secret_key(&self.secp_ctx, &htlc_base_key))))
+                                               Storage::Local { ref keys, .. } => {
+                                                       (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &keys.pubkeys().revocation_basepoint)),
+                                                       ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, revocation_point, &keys.pubkeys().htlc_basepoint)))
                                                },
                                                Storage::Watchtower { ref revocation_base_key, ref htlc_base_key, .. } => {
                                                        (ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, revocation_point, &revocation_base_key)),
@@ -1772,11 +1828,11 @@ impl ChannelMonitor {
                                        let mut inputs_info = Vec::new();
 
                                        macro_rules! sign_input {
-                                               ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr) => {
+                                               ($sighash_parts: expr, $input: expr, $amount: expr, $preimage: expr, $idx: expr) => {
                                                        {
                                                                let (sig, redeemscript, htlc_key) = match self.key_storage {
                                                                        Storage::Local { ref htlc_base_key, .. } => {
-                                                                               let htlc = &per_commitment_option.unwrap()[$input.sequence as usize].0;
+                                                                               let htlc = &per_commitment_option.unwrap()[$idx as usize].0;
                                                                                let redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(htlc, &a_htlc_key, &b_htlc_key, &revocation_pubkey);
                                                                                let sighash = hash_to_message!(&$sighash_parts.sighash_all(&$input, &redeemscript, $amount)[..]);
                                                                                let htlc_key = ignore_error!(chan_utils::derive_private_key(&self.secp_ctx, revocation_point, &htlc_base_key));
@@ -1811,13 +1867,13 @@ impl ChannelMonitor {
                                                                                        vout: transaction_output_index,
                                                                                },
                                                                                script_sig: Script::new(),
-                                                                               sequence: idx as u32, // reset to 0xfffffffd in sign_input
+                                                                               sequence: 0xff_ff_ff_fd,
                                                                                witness: Vec::new(),
                                                                        };
                                                                        if htlc.cltv_expiry > height + CLTV_SHARED_CLAIM_BUFFER {
                                                                                inputs.push(input);
                                                                                inputs_desc.push(if htlc.offered { InputDescriptors::OfferedHTLC } else { InputDescriptors::ReceivedHTLC });
-                                                                               inputs_info.push((payment_preimage, tx.output[transaction_output_index as usize].value, htlc.cltv_expiry));
+                                                                               inputs_info.push((payment_preimage, tx.output[transaction_output_index as usize].value, htlc.cltv_expiry, idx));
                                                                                total_value += tx.output[transaction_output_index as usize].value;
                                                                        } else {
                                                                                let mut single_htlc_tx = Transaction {
@@ -1834,7 +1890,7 @@ impl ChannelMonitor {
                                                                                let mut used_feerate;
                                                                                if subtract_high_prio_fee!(self, fee_estimator, single_htlc_tx.output[0].value, predicted_weight, used_feerate) {
                                                                                        let sighash_parts = bip143::SighashComponents::new(&single_htlc_tx);
-                                                                                       let (redeemscript, htlc_key) = sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.0.to_vec());
+                                                                                       let (redeemscript, htlc_key) = sign_input!(sighash_parts, single_htlc_tx.input[0], htlc.amount_msat / 1000, payment_preimage.0.to_vec(), idx);
                                                                                        assert!(predicted_weight >= single_htlc_tx.get_weight());
                                                                                        spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
                                                                                                outpoint: BitcoinOutPoint { txid: single_htlc_tx.txid(), vout: 0 },
@@ -1865,7 +1921,7 @@ impl ChannelMonitor {
                                                                                vout: transaction_output_index,
                                                                        },
                                                                        script_sig: Script::new(),
-                                                                       sequence: idx as u32,
+                                                                       sequence: 0xff_ff_ff_fd,
                                                                        witness: Vec::new(),
                                                                };
                                                                let mut timeout_tx = Transaction {
@@ -1882,7 +1938,7 @@ impl ChannelMonitor {
                                                                let mut used_feerate;
                                                                if subtract_high_prio_fee!(self, fee_estimator, timeout_tx.output[0].value, predicted_weight, used_feerate) {
                                                                        let sighash_parts = bip143::SighashComponents::new(&timeout_tx);
-                                                                       let (redeemscript, htlc_key) = sign_input!(sighash_parts, timeout_tx.input[0], htlc.amount_msat / 1000, vec![0]);
+                                                                       let (redeemscript, htlc_key) = sign_input!(sighash_parts, timeout_tx.input[0], htlc.amount_msat / 1000, vec![0], idx);
                                                                        assert!(predicted_weight >= timeout_tx.get_weight());
                                                                        //TODO: track SpendableOutputDescriptor
                                                                        log_trace!(self, "Outpoint {}:{} is being being claimed, if it doesn't succeed, a bumped claiming txn is going to be broadcast at height {}", timeout_tx.input[0].previous_output.txid, timeout_tx.input[0].previous_output.vout, height_timer);
@@ -1934,7 +1990,7 @@ impl ChannelMonitor {
                                        let height_timer = Self::get_height_timer(height, soonest_timelock);
                                        let spend_txid = spend_tx.txid();
                                        for (input, info) in spend_tx.input.iter_mut().zip(inputs_info.iter()) {
-                                               let (redeemscript, htlc_key) = sign_input!(sighash_parts, input, info.1, (info.0).0.to_vec());
+                                               let (redeemscript, htlc_key) = sign_input!(sighash_parts, input, info.1, (info.0).0.to_vec(), info.3);
                                                log_trace!(self, "Outpoint {}:{} is being being claimed, if it doesn't succeed, a bumped claiming txn is going to be broadcast at height {}", input.previous_output.txid, input.previous_output.vout, height_timer);
                                                per_input_material.insert(input.previous_output, InputMaterial::RemoteHTLC { script: redeemscript, key: htlc_key, preimage: Some(*(info.0)), amount: info.1, locktime: 0});
                                                match self.claimable_outpoints.entry(input.previous_output) {
@@ -1989,8 +2045,8 @@ impl ChannelMonitor {
                let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
                let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
                let revocation_pubkey = match self.key_storage {
-                       Storage::Local { ref revocation_base_key, .. } => {
-                               ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &PublicKey::from_secret_key(&self.secp_ctx, &revocation_base_key)))
+                       Storage::Local { ref keys, .. } => {
+                               ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &keys.pubkeys().revocation_basepoint))
                        },
                        Storage::Watchtower { ref revocation_base_key, .. } => {
                                ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &revocation_base_key))
@@ -2058,7 +2114,7 @@ impl ChannelMonitor {
                        assert!(predicted_weight >= spend_tx.get_weight());
                        let outpoint = BitcoinOutPoint { txid: spend_tx.txid(), vout: 0 };
                        let output = spend_tx.output[0].clone();
-                       let height_timer = Self::get_height_timer(height, self.their_to_self_delay.unwrap() as u32); // We can safely unwrap given we are past channel opening
+                       let height_timer = Self::get_height_timer(height, height + self.our_to_self_delay as u32);
                        log_trace!(self, "Outpoint {}:{} is being being claimed, if it doesn't succeed, a bumped claiming txn is going to be broadcast at height {}", spend_tx.input[0].previous_output.txid, spend_tx.input[0].previous_output.vout, height_timer);
                        let mut per_input_material = HashMap::with_capacity(1);
                        per_input_material.insert(spend_tx.input[0].previous_output, InputMaterial::Revoked { script: redeemscript, pubkey: None, key: revocation_key, is_htlc: false, amount: tx.output[0].value });
@@ -2219,7 +2275,8 @@ impl ChannelMonitor {
                                assert!(local_tx.tx.has_local_sig());
                                match self.key_storage {
                                        Storage::Local { ref delayed_payment_base_key, .. } => {
-                                               append_onchain_update!(self.broadcast_by_local_state(local_tx, delayed_payment_base_key, height));
+                                               let mut res = self.broadcast_by_local_state(local_tx, delayed_payment_base_key, height);
+                                               append_onchain_update!(res);
                                        },
                                        Storage::Watchtower { .. } => { }
                                }
@@ -2242,7 +2299,8 @@ impl ChannelMonitor {
                                assert!(local_tx.tx.has_local_sig());
                                match self.key_storage {
                                        Storage::Local { ref delayed_payment_base_key, .. } => {
-                                               append_onchain_update!(self.broadcast_by_local_state(local_tx, delayed_payment_base_key, height));
+                                               let mut res = self.broadcast_by_local_state(local_tx, delayed_payment_base_key, height);
+                                               append_onchain_update!(res);
                                        },
                                        Storage::Watchtower { .. } => { }
                                }
@@ -2333,11 +2391,26 @@ impl ChannelMonitor {
                }
        }
 
-       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)>) {
+       /// Called by SimpleManyChannelMonitor::block_connected, which implements
+       /// ChainListener::block_connected.
+       /// 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<B: Deref>(&mut self, txn_matched: &[&Transaction], height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: &FeeEstimator)-> (Vec<(Sha256dHash, Vec<TxOut>)>, Vec<SpendableOutputDescriptor>)
+               where B::Target: BroadcasterInterface
+       {
+               for tx in txn_matched {
+                       let mut output_val = 0;
+                       for out in tx.output.iter() {
+                               if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
+                               output_val += out.value;
+                               if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
+                       }
+               }
+
                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 {
@@ -2396,10 +2469,7 @@ impl ChannelMonitor {
                        // 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();
@@ -2522,7 +2592,11 @@ impl ChannelMonitor {
                                        },
                                        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);
@@ -2551,10 +2625,16 @@ impl ChannelMonitor {
                        }
                }
                self.last_block_hash = block_hash.clone();
-               (watch_outputs, spendable_outputs, htlc_updated)
+               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)
        }
 
-       fn block_disconnected(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: &BroadcasterInterface, fee_estimator: &FeeEstimator) {
+       fn block_disconnected<B: Deref>(&mut self, height: u32, block_hash: &Sha256dHash, broadcaster: B, fee_estimator: &FeeEstimator)
+               where B::Target: BroadcasterInterface
+       {
+               log_trace!(self, "Block {} at height {} disconnected", block_hash, height);
                let mut bump_candidates = HashMap::new();
                if let Some(events) = self.onchain_events_waiting_threshold_conf.remove(&(height + ANTI_REORG_DELAY - 1)) {
                        //We may discard:
@@ -2670,9 +2750,7 @@ impl ChannelMonitor {
 
        /// 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)
@@ -2772,10 +2850,18 @@ impl ChannelMonitor {
                                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) {
@@ -2798,7 +2884,6 @@ impl ChannelMonitor {
                                }
                        }
                }
-               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
@@ -2869,7 +2954,6 @@ impl ChannelMonitor {
                for per_outp_material in cached_claim_datas.per_input_material.values() {
                        match per_outp_material {
                                &InputMaterial::Revoked { ref script, ref is_htlc, ref amount, .. } => {
-                                       log_trace!(self, "Is HLTC ? {}", is_htlc);
                                        inputs_witnesses_weight += Self::get_witnesses_weight(if !is_htlc { &[InputDescriptors::RevokedOutput] } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::OfferedHTLC) { &[InputDescriptors::RevokedOfferedHTLC] } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::AcceptedHTLC) { &[InputDescriptors::RevokedReceivedHTLC] } else { unreachable!() });
                                        amt += *amount;
                                },
@@ -2942,7 +3026,7 @@ impl ChannelMonitor {
 
 const MAX_ALLOC_SIZE: usize = 64*1024;
 
-impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor) {
+impl<R: ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelMonitor<ChanSigner>) {
        fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
                let secp_ctx = Secp256k1::new();
                macro_rules! unwrap_obj {
@@ -2964,6 +3048,7 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
 
                let key_storage = match <u8 as Readable<R>>::read(reader)? {
                        0 => {
+                               let keys = Readable::read(reader)?;
                                let funding_key = Readable::read(reader)?;
                                let revocation_base_key = Readable::read(reader)?;
                                let htlc_base_key = Readable::read(reader)?;
@@ -2980,6 +3065,7 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
                                let current_remote_commitment_txid = Readable::read(reader)?;
                                let prev_remote_commitment_txid = Readable::read(reader)?;
                                Storage::Local {
+                                       keys,
                                        funding_key,
                                        revocation_base_key,
                                        htlc_base_key,
@@ -3138,6 +3224,12 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
                        }
                }
 
+               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)? {
@@ -3201,6 +3293,20 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
                        onchain_events_waiting_threshold_conf.insert(height_target, events);
                }
 
+               let outputs_to_watch_len: u64 = Readable::read(reader)?;
+               let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Sha256dHash>() + mem::size_of::<Vec<Script>>())));
+               for _ in 0..outputs_to_watch_len {
+                       let txid = Readable::read(reader)?;
+                       let outputs_len: u64 = Readable::read(reader)?;
+                       let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Script>()));
+                       for _ in 0..outputs_len {
+                               outputs.push(Readable::read(reader)?);
+                       }
+                       if let Some(_) = outputs_to_watch.insert(txid, outputs) {
+                               return Err(DecodeError::InvalidValue);
+                       }
+               }
+
                Ok((last_block_hash.clone(), ChannelMonitor {
                        commitment_transaction_number_obscure_factor,
 
@@ -3224,6 +3330,7 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
                        current_remote_commitment_number,
 
                        payment_preimages,
+                       pending_htlcs_updated,
 
                        destination_script,
                        to_remote_rescue,
@@ -3233,6 +3340,7 @@ impl<R: ::std::io::Read> ReadableArgs<R, Arc<Logger>> for (Sha256dHash, ChannelM
                        claimable_outpoints,
 
                        onchain_events_waiting_threshold_conf,
+                       outputs_to_watch,
 
                        last_block_hash,
                        secp_ctx,
@@ -3263,12 +3371,14 @@ mod tests {
        use secp256k1::Secp256k1;
        use rand::{thread_rng,Rng};
        use std::sync::Arc;
+       use chain::keysinterface::InMemoryChannelKeys;
+
 
        #[test]
        fn test_per_commitment_storage() {
                // Test vectors from BOLT 3:
                let mut secrets: Vec<[u8; 32]> = Vec::new();
-               let mut monitor: ChannelMonitor;
+               let mut monitor: ChannelMonitor<InMemoryChannelKeys>;
                let secp_ctx = Secp256k1::new();
                let logger = Arc::new(TestLogger::new());
 
@@ -3284,9 +3394,20 @@ mod tests {
                        };
                }
 
+               let keys = InMemoryChannelKeys::new(
+                       &secp_ctx,
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       [41; 32],
+                       0,
+               );
+
                {
                        // insert_secret correct sequence
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3332,7 +3453,7 @@ mod tests {
 
                {
                        // insert_secret #1 incorrect
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3348,7 +3469,7 @@ mod tests {
 
                {
                        // insert_secret #2 incorrect (#1 derived from incorrect)
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3374,7 +3495,7 @@ mod tests {
 
                {
                        // insert_secret #3 incorrect
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3400,7 +3521,7 @@ mod tests {
 
                {
                        // insert_secret #4 incorrect (1,2,3 derived from incorrect)
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3446,7 +3567,7 @@ mod tests {
 
                {
                        // insert_secret #5 incorrect
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3482,7 +3603,7 @@ mod tests {
 
                {
                        // insert_secret #6 incorrect (5 derived from incorrect)
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3528,7 +3649,7 @@ mod tests {
 
                {
                        // insert_secret #7 incorrect
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3574,7 +3695,7 @@ mod tests {
 
                {
                        // insert_secret #8 incorrect
-                       monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+                       monitor = ChannelMonitor::new(keys.clone(), &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                        secrets.clear();
 
                        secrets.push([0; 32]);
@@ -3687,9 +3808,20 @@ mod tests {
                        }
                }
 
+               let keys = InMemoryChannelKeys::new(
+                       &secp_ctx,
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       SecretKey::from_slice(&[41; 32]).unwrap(),
+                       [41; 32],
+                       0,
+               );
+
                // Prune with one old state and a local commitment tx holding a few overlaps with the
                // old state.
-               let mut monitor = ChannelMonitor::new(&SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
+               let mut monitor = ChannelMonitor::new(keys, &SecretKey::from_slice(&[41; 32]).unwrap(), &SecretKey::from_slice(&[42; 32]).unwrap(), &SecretKey::from_slice(&[43; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &SecretKey::from_slice(&[44; 32]).unwrap(), &PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()), 0, Script::new(), logger.clone());
                monitor.their_to_self_delay = Some(10);
 
                monitor.provide_latest_local_commitment_tx_info(LocalCommitmentTransaction::dummy(), dummy_keys!(), 0, preimages_to_local_htlcs!(preimages[0..10]));
@@ -3800,7 +3932,7 @@ mod tests {
                for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
                        sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
                }
-               assert_eq!(base_weight + ChannelMonitor::get_witnesses_weight(&inputs_des[..]),  claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
+               assert_eq!(base_weight + ChannelMonitor::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]),  claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
 
                // Claim tx with 1 offered HTLCs, 3 received HTLCs
                claim_tx.input.clear();
@@ -3822,7 +3954,7 @@ mod tests {
                for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
                        sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
                }
-               assert_eq!(base_weight + ChannelMonitor::get_witnesses_weight(&inputs_des[..]),  claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
+               assert_eq!(base_weight + ChannelMonitor::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]),  claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_des.len() - sum_actual_sigs));
 
                // Justice tx with 1 revoked HTLC-Success tx output
                claim_tx.input.clear();
@@ -3842,7 +3974,7 @@ mod tests {
                for (idx, inp) in claim_tx.input.iter_mut().zip(inputs_des.iter()).enumerate() {
                        sign_input!(sighash_parts, inp.0, idx as u32, 0, inp.1, sum_actual_sigs);
                }
-               assert_eq!(base_weight + ChannelMonitor::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
+               assert_eq!(base_weight + ChannelMonitor::<InMemoryChannelKeys>::get_witnesses_weight(&inputs_des[..]), claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_des.len() - sum_actual_sigs));
        }
 
        // Further testing is done in the ChannelManager integration tests.