Merge pull request #1791 from valentinewallace/2022-10-we-are-intro-node
[rust-lightning] / lightning / src / ln / channelmanager.rs
index 8c12f5470b9ca0fd36f2e5410efeece305c99d71..358af825dd4b18155e692269c465ded24db40d49 100644 (file)
@@ -34,39 +34,39 @@ use bitcoin::secp256k1::Secp256k1;
 use bitcoin::secp256k1::ecdh::SharedSecret;
 use bitcoin::{LockTime, secp256k1, Sequence};
 
-use chain;
-use chain::{Confirm, ChannelMonitorUpdateErr, Watch, BestBlock};
-use chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator, LowerBoundedFeeEstimator};
-use chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent, CLOSED_CHANNEL_UPDATE_ID};
-use chain::transaction::{OutPoint, TransactionData};
+use crate::chain;
+use crate::chain::{Confirm, ChannelMonitorUpdateStatus, Watch, BestBlock};
+use crate::chain::chaininterface::{BroadcasterInterface, ConfirmationTarget, FeeEstimator, LowerBoundedFeeEstimator};
+use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, HTLC_FAIL_BACK_BUFFER, CLTV_CLAIM_BUFFER, LATENCY_GRACE_PERIOD_BLOCKS, ANTI_REORG_DELAY, MonitorEvent, CLOSED_CHANNEL_UPDATE_ID};
+use crate::chain::transaction::{OutPoint, TransactionData};
 // Since this struct is returned in `list_channels` methods, expose it here in case users want to
 // construct one themselves.
-use ln::{inbound_payment, PaymentHash, PaymentPreimage, PaymentSecret};
-use ln::channel::{Channel, ChannelError, ChannelUpdateStatus, UpdateFulfillCommitFetch};
-use ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
+use crate::ln::{inbound_payment, PaymentHash, PaymentPreimage, PaymentSecret};
+use crate::ln::channel::{Channel, ChannelError, ChannelUpdateStatus, UpdateFulfillCommitFetch};
+use crate::ln::features::{ChannelFeatures, ChannelTypeFeatures, InitFeatures, NodeFeatures};
 #[cfg(any(feature = "_test_utils", test))]
-use ln::features::InvoiceFeatures;
-use routing::router::{PaymentParameters, Route, RouteHop, RoutePath, RouteParameters};
-use ln::msgs;
-use ln::onion_utils;
-use ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, MAX_VALUE_MSAT};
-use ln::wire::Encode;
-use chain::keysinterface::{Sign, KeysInterface, KeysManager, InMemorySigner, Recipient};
-use util::config::{UserConfig, ChannelConfig};
-use util::events::{EventHandler, EventsProvider, MessageSendEvent, MessageSendEventsProvider, ClosureReason, HTLCDestination};
-use util::{byte_utils, events};
-use util::wakers::{Future, Notifier};
-use util::scid_utils::fake_scid;
-use util::ser::{BigSize, FixedLengthReader, Readable, ReadableArgs, MaybeReadable, Writeable, Writer, VecWriter};
-use util::logger::{Level, Logger};
-use util::errors::APIError;
-
-use io;
-use prelude::*;
+use crate::ln::features::InvoiceFeatures;
+use crate::routing::router::{PaymentParameters, Route, RouteHop, RoutePath, RouteParameters};
+use crate::ln::msgs;
+use crate::ln::onion_utils;
+use crate::ln::msgs::{ChannelMessageHandler, DecodeError, LightningError, MAX_VALUE_MSAT};
+use crate::ln::wire::Encode;
+use crate::chain::keysinterface::{Sign, KeysInterface, KeysManager, Recipient};
+use crate::util::config::{UserConfig, ChannelConfig};
+use crate::util::events::{EventHandler, EventsProvider, MessageSendEvent, MessageSendEventsProvider, ClosureReason, HTLCDestination};
+use crate::util::{byte_utils, events};
+use crate::util::wakers::{Future, Notifier};
+use crate::util::scid_utils::fake_scid;
+use crate::util::ser::{BigSize, FixedLengthReader, Readable, ReadableArgs, MaybeReadable, Writeable, Writer, VecWriter};
+use crate::util::logger::{Level, Logger};
+use crate::util::errors::APIError;
+
+use crate::io;
+use crate::prelude::*;
 use core::{cmp, mem};
 use core::cell::RefCell;
-use io::Read;
-use sync::{Arc, Mutex, MutexGuard, RwLock, RwLockReadGuard};
+use crate::io::Read;
+use crate::sync::{Arc, Mutex, MutexGuard, RwLock, RwLockReadGuard};
 use core::sync::atomic::{AtomicUsize, Ordering};
 use core::time::Duration;
 use core::ops::Deref;
@@ -617,7 +617,7 @@ impl PendingOutboundPayment {
 /// concrete type of the KeysManager.
 ///
 /// (C-not exported) as Arcs don't make sense in bindings
-pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<InMemorySigner, Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>;
+pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<Arc<M>, Arc<T>, Arc<KeysManager>, Arc<F>, Arc<L>>;
 
 /// SimpleRefChannelManager is a type alias for a ChannelManager reference, and is the reference
 /// counterpart to the SimpleArcChannelManager type alias. Use this type by default when you don't
@@ -629,7 +629,7 @@ pub type SimpleArcChannelManager<M, T, F, L> = ChannelManager<InMemorySigner, Ar
 /// concrete type of the KeysManager.
 ///
 /// (C-not exported) as Arcs don't make sense in bindings
-pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<InMemorySigner, &'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
+pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManager<&'a M, &'b T, &'c KeysManager, &'d F, &'e L>;
 
 /// Manager which keeps track of a number of channels and sends messages to the appropriate
 /// channel, also tracking HTLC preimages and forwarding onion packets appropriately.
@@ -699,10 +699,10 @@ pub type SimpleRefChannelManager<'a, 'b, 'c, 'd, 'e, M, T, F, L> = ChannelManage
 //  |                   |
 //  |                   |__`pending_background_events`
 //
-pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
-       where M::Target: chain::Watch<Signer>,
+pub struct ChannelManager<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
                                L::Target: Logger,
 {
@@ -721,9 +721,9 @@ pub struct ChannelManager<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref,
 
        /// See `ChannelManager` struct-level documentation for lock order requirements.
        #[cfg(any(test, feature = "_test_utils"))]
-       pub(super) channel_state: Mutex<ChannelHolder<Signer>>,
+       pub(super) channel_state: Mutex<ChannelHolder<<K::Target as KeysInterface>::Signer>>,
        #[cfg(not(any(test, feature = "_test_utils")))]
-       channel_state: Mutex<ChannelHolder<Signer>>,
+       channel_state: Mutex<ChannelHolder<<K::Target as KeysInterface>::Signer>>,
 
        /// Storage for PaymentSecrets and any requirements on future inbound payments before we will
        /// expose them to users via a PaymentReceived event. HTLCs which do not meet the requirements
@@ -1212,13 +1212,13 @@ pub enum PaymentSendFailure {
        /// in over-/re-payment.
        ///
        /// The results here are ordered the same as the paths in the route object which was passed to
-       /// send_payment, and any Errs which are not APIError::MonitorUpdateFailed can be safely
-       /// retried (though there is currently no API with which to do so).
+       /// send_payment, and any `Err`s which are not [`APIError::MonitorUpdateInProgress`] can be
+       /// safely retried via [`ChannelManager::retry_payment`].
        ///
-       /// Any entries which contain Err(APIError::MonitorUpdateFailed) or Ok(()) MUST NOT be retried
-       /// as they will result in over-/re-payment. These HTLCs all either successfully sent (in the
-       /// case of Ok(())) or will send once channel_monitor_updated is called on the next-hop channel
-       /// with the latest update_id.
+       /// Any entries which contain `Err(APIError::MonitorUpdateInprogress)` or `Ok(())` MUST NOT be
+       /// retried as they will result in over-/re-payment. These HTLCs all either successfully sent
+       /// (in the case of `Ok(())`) or will send once a [`MonitorEvent::Completed`] is provided for
+       /// the next-hop channel with the latest update_id.
        PartialFailure {
                /// The errors themselves, in the same order as the route hops.
                results: Vec<Result<(), APIError>>,
@@ -1375,11 +1375,11 @@ macro_rules! remove_channel {
        }
 }
 
-macro_rules! handle_monitor_err {
+macro_rules! handle_monitor_update_res {
        ($self: ident, $err: expr, $short_to_chan_info: expr, $chan: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $resend_channel_ready: expr, $failed_forwards: expr, $failed_fails: expr, $failed_finalized_fulfills: expr, $chan_id: expr) => {
                match $err {
-                       ChannelMonitorUpdateErr::PermanentFailure => {
-                               log_error!($self.logger, "Closing channel {} due to monitor update ChannelMonitorUpdateErr::PermanentFailure", log_bytes!($chan_id[..]));
+                       ChannelMonitorUpdateStatus::PermanentFailure => {
+                               log_error!($self.logger, "Closing channel {} due to monitor update ChannelMonitorUpdateStatus::PermanentFailure", log_bytes!($chan_id[..]));
                                update_maps_on_chan_removal!($self, $short_to_chan_info, $chan);
                                // TODO: $failed_fails is dropped here, which will cause other channels to hit the
                                // chain in a confused state! We need to move them into the ChannelMonitor which
@@ -1391,11 +1391,11 @@ macro_rules! handle_monitor_err {
                                // given up the preimage yet, so might as well just wait until the payment is
                                // retried, avoiding the on-chain fees.
                                let res: Result<(), _> = Err(MsgHandleErrInternal::from_finish_shutdown("ChannelMonitor storage failure".to_owned(), *$chan_id, $chan.get_user_id(),
-                                               $chan.force_shutdown(true), $self.get_channel_update_for_broadcast(&$chan).ok() ));
+                                               $chan.force_shutdown(false), $self.get_channel_update_for_broadcast(&$chan).ok() ));
                                (res, true)
                        },
-                       ChannelMonitorUpdateErr::TemporaryFailure => {
-                               log_info!($self.logger, "Disabling channel {} due to monitor update TemporaryFailure. On restore will send {} and process {} forwards, {} fails, and {} fulfill finalizations",
+                       ChannelMonitorUpdateStatus::InProgress => {
+                               log_info!($self.logger, "Disabling channel {} due to monitor update in progress. On restore will send {} and process {} forwards, {} fails, and {} fulfill finalizations",
                                                log_bytes!($chan_id[..]),
                                                if $resend_commitment && $resend_raa {
                                                                match $action_type {
@@ -1414,13 +1414,16 @@ macro_rules! handle_monitor_err {
                                if !$resend_raa {
                                        debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst || !$resend_commitment);
                                }
-                               $chan.monitor_update_failed($resend_raa, $resend_commitment, $resend_channel_ready, $failed_forwards, $failed_fails, $failed_finalized_fulfills);
+                               $chan.monitor_updating_paused($resend_raa, $resend_commitment, $resend_channel_ready, $failed_forwards, $failed_fails, $failed_finalized_fulfills);
                                (Err(MsgHandleErrInternal::from_chan_no_close(ChannelError::Ignore("Failed to update ChannelMonitor".to_owned()), *$chan_id)), false)
                        },
+                       ChannelMonitorUpdateStatus::Completed => {
+                               (Ok(()), false)
+                       },
                }
        };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $resend_channel_ready: expr, $failed_forwards: expr, $failed_fails: expr, $failed_finalized_fulfills: expr) => { {
-               let (res, drop) = handle_monitor_err!($self, $err, $channel_state.short_to_chan_info, $entry.get_mut(), $action_type, $resend_raa, $resend_commitment, $resend_channel_ready, $failed_forwards, $failed_fails, $failed_finalized_fulfills, $entry.key());
+               let (res, drop) = handle_monitor_update_res!($self, $err, $channel_state.short_to_chan_info, $entry.get_mut(), $action_type, $resend_raa, $resend_commitment, $resend_channel_ready, $failed_forwards, $failed_fails, $failed_finalized_fulfills, $entry.key());
                if drop {
                        $entry.remove_entry();
                }
@@ -1428,41 +1431,20 @@ macro_rules! handle_monitor_err {
        } };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $chan_id: expr, COMMITMENT_UPDATE_ONLY) => { {
                debug_assert!($action_type == RAACommitmentOrder::CommitmentFirst);
-               handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, false, true, false, Vec::new(), Vec::new(), Vec::new(), $chan_id)
+               handle_monitor_update_res!($self, $err, $channel_state, $entry, $action_type, false, true, false, Vec::new(), Vec::new(), Vec::new(), $chan_id)
        } };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $chan_id: expr, NO_UPDATE) => {
-               handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, false, false, false, Vec::new(), Vec::new(), Vec::new(), $chan_id)
+               handle_monitor_update_res!($self, $err, $channel_state, $entry, $action_type, false, false, false, Vec::new(), Vec::new(), Vec::new(), $chan_id)
        };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_channel_ready: expr, OPTIONALLY_RESEND_FUNDING_LOCKED) => {
-               handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, false, false, $resend_channel_ready, Vec::new(), Vec::new(), Vec::new())
+               handle_monitor_update_res!($self, $err, $channel_state, $entry, $action_type, false, false, $resend_channel_ready, Vec::new(), Vec::new(), Vec::new())
        };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
-               handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, false, Vec::new(), Vec::new(), Vec::new())
+               handle_monitor_update_res!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, false, Vec::new(), Vec::new(), Vec::new())
        };
        ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
-               handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, false, $failed_forwards, $failed_fails, Vec::new())
-       };
-}
-
-macro_rules! return_monitor_err {
-       ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
-               return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment);
+               handle_monitor_update_res!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, false, $failed_forwards, $failed_fails, Vec::new())
        };
-       ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr, $failed_forwards: expr, $failed_fails: expr) => {
-               return handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment, $failed_forwards, $failed_fails);
-       }
-}
-
-// Does not break in case of TemporaryFailure!
-macro_rules! maybe_break_monitor_err {
-       ($self: ident, $err: expr, $channel_state: expr, $entry: expr, $action_type: path, $resend_raa: expr, $resend_commitment: expr) => {
-               match (handle_monitor_err!($self, $err, $channel_state, $entry, $action_type, $resend_raa, $resend_commitment), $err) {
-                       (e, ChannelMonitorUpdateErr::PermanentFailure) => {
-                               break e;
-                       },
-                       (_, ChannelMonitorUpdateErr::TemporaryFailure) => { },
-               }
-       }
 }
 
 macro_rules! send_channel_ready {
@@ -1539,15 +1521,18 @@ macro_rules! handle_chan_restoration_locked {
                                // only case where we can get a new ChannelMonitorUpdate would be if we also
                                // have some commitment updates to send as well.
                                assert!($commitment_update.is_some());
-                               if let Err(e) = $self.chain_monitor.update_channel($channel_entry.get().get_funding_txo().unwrap(), monitor_update) {
-                                       // channel_reestablish doesn't guarantee the order it returns is sensical
-                                       // for the messages it returns, but if we're setting what messages to
-                                       // re-transmit on monitor update success, we need to make sure it is sane.
-                                       let mut order = $order;
-                                       if $raa.is_none() {
-                                               order = RAACommitmentOrder::CommitmentFirst;
+                               match $self.chain_monitor.update_channel($channel_entry.get().get_funding_txo().unwrap(), monitor_update) {
+                                       ChannelMonitorUpdateStatus::Completed => {},
+                                       e => {
+                                               // channel_reestablish doesn't guarantee the order it returns is sensical
+                                               // for the messages it returns, but if we're setting what messages to
+                                               // re-transmit on monitor update success, we need to make sure it is sane.
+                                               let mut order = $order;
+                                               if $raa.is_none() {
+                                                       order = RAACommitmentOrder::CommitmentFirst;
+                                               }
+                                               break handle_monitor_update_res!($self, e, $channel_state, $channel_entry, order, $raa.is_some(), true);
                                        }
-                                       break handle_monitor_err!($self, e, $channel_state, $channel_entry, order, $raa.is_some(), true);
                                }
                        }
 
@@ -1607,10 +1592,10 @@ macro_rules! post_handle_chan_restoration {
        } }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<Signer, M, T, K, F, L>
-       where M::Target: chain::Watch<Signer>,
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F, L>
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
@@ -1776,7 +1761,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                Ok(temporary_channel_id)
        }
 
-       fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<Signer>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
+       fn list_channels_with_filter<Fn: FnMut(&(&[u8; 32], &Channel<<K::Target as KeysInterface>::Signer>)) -> bool>(&self, f: Fn) -> Vec<ChannelDetails> {
                let mut res = Vec::new();
                {
                        let channel_state = self.channel_state.lock().unwrap();
@@ -1858,7 +1843,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        }
 
        /// Helper function that issues the channel close events
-       fn issue_channel_close_events(&self, channel: &Channel<Signer>, closure_reason: ClosureReason) {
+       fn issue_channel_close_events(&self, channel: &Channel<<K::Target as KeysInterface>::Signer>, closure_reason: ClosureReason) {
                let mut pending_events_lock = self.pending_events.lock().unwrap();
                match channel.unbroadcasted_funding() {
                        Some(transaction) => {
@@ -1898,13 +1883,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                                        // Update the monitor with the shutdown script if necessary.
                                        if let Some(monitor_update) = monitor_update {
-                                               if let Err(e) = self.chain_monitor.update_channel(chan_entry.get().get_funding_txo().unwrap(), monitor_update) {
-                                                       let (result, is_permanent) =
-                                                               handle_monitor_err!(self, e, channel_state.short_to_chan_info, chan_entry.get_mut(), RAACommitmentOrder::CommitmentFirst, chan_entry.key(), NO_UPDATE);
-                                                       if is_permanent {
-                                                               remove_channel!(self, channel_state, chan_entry);
-                                                               break result;
-                                                       }
+                                               let update_res = self.chain_monitor.update_channel(chan_entry.get().get_funding_txo().unwrap(), monitor_update);
+                                               let (result, is_permanent) =
+                                                       handle_monitor_update_res!(self, update_res, channel_state.short_to_chan_info, chan_entry.get_mut(), RAACommitmentOrder::CommitmentFirst, chan_entry.key(), NO_UPDATE);
+                                               if is_permanent {
+                                                       remove_channel!(self, channel_state, chan_entry);
+                                                       break result;
                                                }
                                        }
 
@@ -1987,7 +1971,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                log_debug!(self.logger, "Finishing force-closure of channel with {} HTLCs to fail", failed_htlcs.len());
                for htlc_source in failed_htlcs.drain(..) {
                        let (source, payment_hash, counterparty_node_id, channel_id) = htlc_source;
-                       let receiver = HTLCDestination::NextHopChannel { node_id: Some(counterparty_node_id), channel_id: channel_id };
+                       let receiver = HTLCDestination::NextHopChannel { node_id: Some(counterparty_node_id), channel_id };
                        self.fail_htlc_backwards_internal(source, &payment_hash, HTLCFailReason::Reason { failure_code: 0x4000 | 8, data: Vec::new() }, receiver);
                }
                if let Some((funding_txo, monitor_update)) = monitor_update_option {
@@ -2395,7 +2379,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// [`MessageSendEvent::BroadcastChannelUpdate`] event.
        ///
        /// May be called with channel_state already locked!
-       fn get_channel_update_for_broadcast(&self, chan: &Channel<Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
+       fn get_channel_update_for_broadcast(&self, chan: &Channel<<K::Target as KeysInterface>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
                if !chan.should_announce() {
                        return Err(LightningError {
                                err: "Cannot broadcast a channel_update for a private channel".to_owned(),
@@ -2414,7 +2398,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// and thus MUST NOT be called unless the recipient of the resulting message has already
        /// provided evidence that they know about the existence of the channel.
        /// May be called with channel_state already locked!
-       fn get_channel_update_for_unicast(&self, chan: &Channel<Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
+       fn get_channel_update_for_unicast(&self, chan: &Channel<<K::Target as KeysInterface>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
                log_trace!(self.logger, "Attempting to generate channel update for channel {}", log_bytes!(chan.channel_id()));
                let short_channel_id = match chan.get_short_channel_id().or(chan.latest_inbound_scid_alias()) {
                        None => return Err(LightningError{err: "Channel not yet established".to_owned(), action: msgs::ErrorAction::IgnoreError}),
@@ -2423,7 +2407,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                self.get_channel_update_for_onion(short_channel_id, chan)
        }
-       fn get_channel_update_for_onion(&self, short_channel_id: u64, chan: &Channel<Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
+       fn get_channel_update_for_onion(&self, short_channel_id: u64, chan: &Channel<<K::Target as KeysInterface>::Signer>) -> Result<msgs::ChannelUpdate, LightningError> {
                log_trace!(self.logger, "Generating channel update for channel {}", log_bytes!(chan.channel_id()));
                let were_node_one = PublicKey::from_secret_key(&self.secp_ctx, &self.our_network_key).serialize()[..] < chan.get_counterparty_node_id().serialize()[..];
 
@@ -2520,19 +2504,30 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        channel_state, chan)
                                } {
                                        Some((update_add, commitment_signed, monitor_update)) => {
-                                               if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                                       maybe_break_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true);
-                                                       // Note that MonitorUpdateFailed here indicates (per function docs)
-                                                       // that we will resend the commitment update once monitor updating
-                                                       // is restored. Therefore, we must return an error indicating that
-                                                       // it is unsafe to retry the payment wholesale, which we do in the
-                                                       // send_payment check for MonitorUpdateFailed, below.
-                                                       insert_outbound_payment!(); // Only do this after possibly break'ing on Perm failure above.
-                                                       return Err(APIError::MonitorUpdateFailed);
+                                               let update_err = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update);
+                                               let chan_id = chan.get().channel_id();
+                                               match (update_err,
+                                                       handle_monitor_update_res!(self, update_err, channel_state, chan,
+                                                               RAACommitmentOrder::CommitmentFirst, false, true))
+                                               {
+                                                       (ChannelMonitorUpdateStatus::PermanentFailure, Err(e)) => break Err(e),
+                                                       (ChannelMonitorUpdateStatus::Completed, Ok(())) => {
+                                                               insert_outbound_payment!();
+                                                       },
+                                                       (ChannelMonitorUpdateStatus::InProgress, Err(_)) => {
+                                                               // Note that MonitorUpdateInProgress here indicates (per function
+                                                               // docs) that we will resend the commitment update once monitor
+                                                               // updating completes. Therefore, we must return an error
+                                                               // indicating that it is unsafe to retry the payment wholesale,
+                                                               // which we do in the send_payment check for
+                                                               // MonitorUpdateInProgress, below.
+                                                               insert_outbound_payment!(); // Only do this after possibly break'ing on Perm failure above.
+                                                               return Err(APIError::MonitorUpdateInProgress);
+                                                       },
+                                                       _ => unreachable!(),
                                                }
-                                               insert_outbound_payment!();
 
-                                               log_debug!(self.logger, "Sending payment along path resulted in a commitment_signed for channel {}", log_bytes!(chan.get().channel_id()));
+                                               log_debug!(self.logger, "Sending payment along path resulted in a commitment_signed for channel {}", log_bytes!(chan_id));
                                                channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
                                                        node_id: path.first().unwrap().pubkey,
                                                        updates: msgs::CommitmentUpdate {
@@ -2578,12 +2573,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        /// PaymentSendFailure for more info.
        ///
        /// In general, a path may raise:
-       ///  * APIError::RouteError when an invalid route or forwarding parameter (cltv_delta, fee,
+       ///  * [`APIError::RouteError`] when an invalid route or forwarding parameter (cltv_delta, fee,
        ///    node public key) is specified.
-       ///  * APIError::ChannelUnavailable if the next-hop channel is not available for updates
+       ///  * [`APIError::ChannelUnavailable`] if the next-hop channel is not available for updates
        ///    (including due to previous monitor update failure or new permanent monitor update
        ///    failure).
-       ///  * APIError::MonitorUpdateFailed if a new monitor update failure prevented sending the
+       ///  * [`APIError::MonitorUpdateInProgress`] if a new monitor update failure prevented sending the
        ///    relevant updates.
        ///
        /// Note that depending on the type of the PaymentSendFailure the HTLC may have been
@@ -2647,8 +2642,8 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                for (res, path) in results.iter().zip(route.paths.iter()) {
                        if res.is_ok() { has_ok = true; }
                        if res.is_err() { has_err = true; }
-                       if let &Err(APIError::MonitorUpdateFailed) = res {
-                               // MonitorUpdateFailed is inherently unsafe to retry, so we call it a
+                       if let &Err(APIError::MonitorUpdateInProgress) = res {
+                               // MonitorUpdateInProgress is inherently unsafe to retry, so we call it a
                                // PartialFailure.
                                has_err = true;
                                has_ok = true;
@@ -2837,7 +2832,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
        /// Handles the generation of a funding transaction, optionally (for tests) with a function
        /// which checks the correctness of the funding transaction given the associated channel.
-       fn funding_transaction_generated_intern<FundingOutput: Fn(&Channel<Signer>, &Transaction) -> Result<OutPoint, APIError>>(
+       fn funding_transaction_generated_intern<FundingOutput: Fn(&Channel<<K::Target as KeysInterface>::Signer>, &Transaction) -> Result<OutPoint, APIError>>(
                &self, temporary_channel_id: &[u8; 32], _counterparty_node_id: &PublicKey, funding_transaction: Transaction, find_funding_output: FundingOutput
        ) -> Result<(), APIError> {
                let (chan, msg) = {
@@ -3250,9 +3245,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                        continue;
                                                                }
                                                        };
-                                                       if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                                               handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
-                                                               continue;
+                                                       match self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
+                                                               ChannelMonitorUpdateStatus::Completed => {},
+                                                               e => {
+                                                                       handle_errors.push((chan.get().get_counterparty_node_id(), handle_monitor_update_res!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, true)));
+                                                                       continue;
+                                                               }
                                                        }
                                                        log_debug!(self.logger, "Forwarding HTLCs resulted in a commitment update with {} HTLCs added and {} HTLCs failed for channel {}",
                                                                add_htlc_msgs.len(), fail_htlc_msgs.len(), log_bytes!(chan.get().channel_id()));
@@ -3494,7 +3492,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                self.process_background_events();
        }
 
-       fn update_channel_fee(&self, short_to_chan_info: &mut HashMap<u64, (PublicKey, [u8; 32])>, pending_msg_events: &mut Vec<events::MessageSendEvent>, chan_id: &[u8; 32], chan: &mut Channel<Signer>, new_feerate: u32) -> (bool, NotifyOption, Result<(), MsgHandleErrInternal>) {
+       fn update_channel_fee(&self, short_to_chan_info: &mut HashMap<u64, (PublicKey, [u8; 32])>, pending_msg_events: &mut Vec<events::MessageSendEvent>, chan_id: &[u8; 32], chan: &mut Channel<<K::Target as KeysInterface>::Signer>, new_feerate: u32) -> (bool, NotifyOption, Result<(), MsgHandleErrInternal>) {
                if !chan.is_outbound() { return (true, NotifyOption::SkipPersist, Ok(())); }
                // If the feerate has decreased by less than half, don't bother
                if new_feerate <= chan.get_feerate() && new_feerate * 2 > chan.get_feerate() {
@@ -3521,23 +3519,26 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                };
                let ret_err = match res {
                        Ok(Some((update_fee, commitment_signed, monitor_update))) => {
-                               if let Err(e) = self.chain_monitor.update_channel(chan.get_funding_txo().unwrap(), monitor_update) {
-                                       let (res, drop) = handle_monitor_err!(self, e, short_to_chan_info, chan, RAACommitmentOrder::CommitmentFirst, chan_id, COMMITMENT_UPDATE_ONLY);
-                                       if drop { retain_channel = false; }
-                                       res
-                               } else {
-                                       pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
-                                               node_id: chan.get_counterparty_node_id(),
-                                               updates: msgs::CommitmentUpdate {
-                                                       update_add_htlcs: Vec::new(),
-                                                       update_fulfill_htlcs: Vec::new(),
-                                                       update_fail_htlcs: Vec::new(),
-                                                       update_fail_malformed_htlcs: Vec::new(),
-                                                       update_fee: Some(update_fee),
-                                                       commitment_signed,
-                                               },
-                                       });
-                                       Ok(())
+                               match self.chain_monitor.update_channel(chan.get_funding_txo().unwrap(), monitor_update) {
+                                       ChannelMonitorUpdateStatus::Completed => {
+                                               pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
+                                                       node_id: chan.get_counterparty_node_id(),
+                                                       updates: msgs::CommitmentUpdate {
+                                                               update_add_htlcs: Vec::new(),
+                                                               update_fulfill_htlcs: Vec::new(),
+                                                               update_fail_htlcs: Vec::new(),
+                                                               update_fail_malformed_htlcs: Vec::new(),
+                                                               update_fee: Some(update_fee),
+                                                               commitment_signed,
+                                                       },
+                                               });
+                                               Ok(())
+                                       },
+                                       e => {
+                                               let (res, drop) = handle_monitor_update_res!(self, e, short_to_chan_info, chan, RAACommitmentOrder::CommitmentFirst, chan_id, COMMITMENT_UPDATE_ONLY);
+                                               if drop { retain_channel = false; }
+                                               res
+                                       }
                                }
                        },
                        Ok(None) => Ok(()),
@@ -3722,7 +3723,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        ///
        /// This is for failures on the channel on which the HTLC was *received*, not failures
        /// forwarding
-       fn get_htlc_inbound_temp_fail_err_and_data(&self, desired_err_code: u16, chan: &Channel<Signer>) -> (u16, Vec<u8>) {
+       fn get_htlc_inbound_temp_fail_err_and_data(&self, desired_err_code: u16, chan: &Channel<<K::Target as KeysInterface>::Signer>) -> (u16, Vec<u8>) {
                // We can't be sure what SCID was used when relaying inbound towards us, so we have to
                // guess somewhat. If its a public channel, we figure best to just use the real SCID (as
                // we're not leaking that we have a channel with the counterparty), otherwise we try to use
@@ -3742,7 +3743,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
        /// Gets an HTLC onion failure code and error data for an `UPDATE` error, given the error code
        /// that we want to return and a channel.
-       fn get_htlc_temp_fail_err_and_data(&self, desired_err_code: u16, scid: u64, chan: &Channel<Signer>) -> (u16, Vec<u8>) {
+       fn get_htlc_temp_fail_err_and_data(&self, desired_err_code: u16, scid: u64, chan: &Channel<<K::Target as KeysInterface>::Signer>) -> (u16, Vec<u8>) {
                debug_assert_eq!(desired_err_code & 0x1000, 0x1000);
                if let Ok(upd) = self.get_channel_update_for_onion(scid, chan) {
                        let mut enc = VecWriter(Vec::with_capacity(upd.serialized_length() + 6));
@@ -3861,7 +3862,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                                }
                                                        } else {
                                                                events::Event::ProbeFailed {
-                                                                       payment_id: payment_id,
+                                                                       payment_id,
                                                                        payment_hash: payment_hash.clone(),
                                                                        path: path.clone(),
                                                                        short_channel_id,
@@ -3908,7 +3909,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                                                if self.payment_is_probe(payment_hash, &payment_id) {
                                                        events::Event::ProbeFailed {
-                                                               payment_id: payment_id,
+                                                               payment_id,
                                                                payment_hash: payment_hash.clone(),
                                                                path: path.clone(),
                                                                short_channel_id: Some(scid),
@@ -4112,7 +4113,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
        }
 
-       fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<Signer>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> ClaimFundsFromHop {
+       fn claim_funds_from_hop(&self, channel_state_lock: &mut MutexGuard<ChannelHolder<<K::Target as KeysInterface>::Signer>>, prev_hop: HTLCPreviousHopData, payment_preimage: PaymentPreimage) -> ClaimFundsFromHop {
                //TODO: Delay the claimed_funds relaying just like we do outbound relay!
                let channel_state = &mut **channel_state_lock;
                let chan_id = match channel_state.short_to_chan_info.get(&prev_hop.short_channel_id) {
@@ -4126,15 +4127,18 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                        match chan.get_mut().get_update_fulfill_htlc_and_commit(prev_hop.htlc_id, payment_preimage, &self.logger) {
                                Ok(msgs_monitor_option) => {
                                        if let UpdateFulfillCommitFetch::NewClaim { msgs, htlc_value_msat, monitor_update } = msgs_monitor_option {
-                                               if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                                       log_given_level!(self.logger, if e == ChannelMonitorUpdateErr::PermanentFailure { Level::Error } else { Level::Debug },
-                                                               "Failed to update channel monitor with preimage {:?}: {:?}",
-                                                               payment_preimage, e);
-                                                       return ClaimFundsFromHop::MonitorUpdateFail(
-                                                               chan.get().get_counterparty_node_id(),
-                                                               handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err(),
-                                                               Some(htlc_value_msat)
-                                                       );
+                                               match self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
+                                                       ChannelMonitorUpdateStatus::Completed => {},
+                                                       e => {
+                                                               log_given_level!(self.logger, if e == ChannelMonitorUpdateStatus::PermanentFailure { Level::Error } else { Level::Debug },
+                                                                       "Failed to update channel monitor with preimage {:?}: {:?}",
+                                                                       payment_preimage, e);
+                                                               return ClaimFundsFromHop::MonitorUpdateFail(
+                                                                       chan.get().get_counterparty_node_id(),
+                                                                       handle_monitor_update_res!(self, e, channel_state, chan, RAACommitmentOrder::CommitmentFirst, false, msgs.is_some()).unwrap_err(),
+                                                                       Some(htlc_value_msat)
+                                                               );
+                                                       }
                                                }
                                                if let Some((msg, commitment_signed)) = msgs {
                                                        log_debug!(self.logger, "Claiming funds for HTLC with preimage {} resulted in a commitment_signed for channel {}",
@@ -4157,10 +4161,13 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        }
                                },
                                Err((e, monitor_update)) => {
-                                       if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                               log_given_level!(self.logger, if e == ChannelMonitorUpdateErr::PermanentFailure { Level::Error } else { Level::Info },
-                                                       "Failed to update channel monitor with preimage {:?} immediately prior to force-close: {:?}",
-                                                       payment_preimage, e);
+                                       match self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
+                                               ChannelMonitorUpdateStatus::Completed => {},
+                                               e => {
+                                                       log_given_level!(self.logger, if e == ChannelMonitorUpdateStatus::PermanentFailure { Level::Error } else { Level::Info },
+                                                               "Failed to update channel monitor with preimage {:?} immediately prior to force-close: {:?}",
+                                                               payment_preimage, e);
+                                               },
                                        }
                                        let counterparty_node_id = chan.get().get_counterparty_node_id();
                                        let (drop, res) = convert_chan_err!(self, e, channel_state.short_to_chan_info, chan.get_mut(), &chan_id);
@@ -4199,7 +4206,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                }
        }
 
-       fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage, forwarded_htlc_value_msat: Option<u64>, from_onchain: bool, next_channel_id: [u8; 32]) {
+       fn claim_funds_internal(&self, mut channel_state_lock: MutexGuard<ChannelHolder<<K::Target as KeysInterface>::Signer>>, source: HTLCSource, payment_preimage: PaymentPreimage, forwarded_htlc_value_msat: Option<u64>, from_onchain: bool, next_channel_id: [u8; 32]) {
                match source {
                        HTLCSource::OutboundRoute { session_priv, payment_id, path, .. } => {
                                mem::drop(channel_state_lock);
@@ -4267,9 +4274,14 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        // We update the ChannelMonitor on the backward link, after
                                        // receiving an offchain preimage event from the forward link (the
                                        // event being update_fulfill_htlc).
-                                       if let Err(e) = self.chain_monitor.update_channel(prev_outpoint, preimage_update) {
+                                       let update_res = self.chain_monitor.update_channel(prev_outpoint, preimage_update);
+                                       if update_res != ChannelMonitorUpdateStatus::Completed {
+                                               // TODO: This needs to be handled somehow - if we receive a monitor update
+                                               // with a preimage we *must* somehow manage to propagate it to the upstream
+                                               // channel, or we must have an ability to receive the same event and try
+                                               // again on restart.
                                                log_error!(self.logger, "Critical error: failed to update channel monitor with preimage {:?}: {:?}",
-                                                                                        payment_preimage, e);
+                                                       payment_preimage, update_res);
                                        }
                                        // Note that we do *not* set `claimed_htlc` to false here. In fact, this
                                        // totally could be a duplicate claim, but we have no way of knowing
@@ -4534,29 +4546,28 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                };
                // Because we have exclusive ownership of the channel here we can release the channel_state
                // lock before watch_channel
-               if let Err(e) = self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor) {
-                       match e {
-                               ChannelMonitorUpdateErr::PermanentFailure => {
-                                       // Note that we reply with the new channel_id in error messages if we gave up on the
-                                       // channel, not the temporary_channel_id. This is compatible with ourselves, but the
-                                       // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
-                                       // any messages referencing a previously-closed channel anyway.
-                                       // We do not do a force-close here as that would generate a monitor update for
-                                       // a monitor that we didn't manage to store (and that we don't care about - we
-                                       // don't respond with the funding_signed so the channel can never go on chain).
-                                       let (_monitor_update, failed_htlcs) = chan.force_shutdown(true);
-                                       assert!(failed_htlcs.is_empty());
-                                       return Err(MsgHandleErrInternal::send_err_msg_no_close("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id));
-                               },
-                               ChannelMonitorUpdateErr::TemporaryFailure => {
-                                       // There's no problem signing a counterparty's funding transaction if our monitor
-                                       // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
-                                       // accepted payment from yet. We do, however, need to wait to send our channel_ready
-                                       // until we have persisted our monitor.
-                                       chan.monitor_update_failed(false, false, channel_ready.is_some(), Vec::new(), Vec::new(), Vec::new());
-                                       channel_ready = None; // Don't send the channel_ready now
-                               },
-                       }
+               match self.chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor) {
+                       ChannelMonitorUpdateStatus::Completed => {},
+                       ChannelMonitorUpdateStatus::PermanentFailure => {
+                               // Note that we reply with the new channel_id in error messages if we gave up on the
+                               // channel, not the temporary_channel_id. This is compatible with ourselves, but the
+                               // spec is somewhat ambiguous here. Not a huge deal since we'll send error messages for
+                               // any messages referencing a previously-closed channel anyway.
+                               // We do not propagate the monitor update to the user as it would be for a monitor
+                               // that we didn't manage to store (and that we don't care about - we don't respond
+                               // with the funding_signed so the channel can never go on chain).
+                               let (_monitor_update, failed_htlcs) = chan.force_shutdown(false);
+                               assert!(failed_htlcs.is_empty());
+                               return Err(MsgHandleErrInternal::send_err_msg_no_close("ChannelMonitor storage failure".to_owned(), funding_msg.channel_id));
+                       },
+                       ChannelMonitorUpdateStatus::InProgress => {
+                               // There's no problem signing a counterparty's funding transaction if our monitor
+                               // hasn't persisted to disk yet - we can't lose money on a transaction that we haven't
+                               // accepted payment from yet. We do, however, need to wait to send our channel_ready
+                               // until we have persisted our monitor.
+                               chan.monitor_updating_paused(false, false, channel_ready.is_some(), Vec::new(), Vec::new(), Vec::new());
+                               channel_ready = None; // Don't send the channel_ready now
+                       },
                }
                let mut channel_state_lock = self.channel_state.lock().unwrap();
                let channel_state = &mut *channel_state_lock;
@@ -4603,17 +4614,20 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                Ok(update) => update,
                                                Err(e) => try_chan_entry!(self, Err(e), channel_state, chan),
                                        };
-                                       if let Err(e) = self.chain_monitor.watch_channel(chan.get().get_funding_txo().unwrap(), monitor) {
-                                               let mut res = handle_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, channel_ready.is_some(), OPTIONALLY_RESEND_FUNDING_LOCKED);
-                                               if let Err(MsgHandleErrInternal { ref mut shutdown_finish, .. }) = res {
-                                                       // We weren't able to watch the channel to begin with, so no updates should be made on
-                                                       // it. Previously, full_stack_target found an (unreachable) panic when the
-                                                       // monitor update contained within `shutdown_finish` was applied.
-                                                       if let Some((ref mut shutdown_finish, _)) = shutdown_finish {
-                                                               shutdown_finish.0.take();
+                                       match self.chain_monitor.watch_channel(chan.get().get_funding_txo().unwrap(), monitor) {
+                                               ChannelMonitorUpdateStatus::Completed => {},
+                                               e => {
+                                                       let mut res = handle_monitor_update_res!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, channel_ready.is_some(), OPTIONALLY_RESEND_FUNDING_LOCKED);
+                                                       if let Err(MsgHandleErrInternal { ref mut shutdown_finish, .. }) = res {
+                                                               // We weren't able to watch the channel to begin with, so no updates should be made on
+                                                               // it. Previously, full_stack_target found an (unreachable) panic when the
+                                                               // monitor update contained within `shutdown_finish` was applied.
+                                                               if let Some((ref mut shutdown_finish, _)) = shutdown_finish {
+                                                                       shutdown_finish.0.take();
+                                                               }
                                                        }
-                                               }
-                                               return res
+                                                       return res
+                                               },
                                        }
                                        if let Some(msg) = channel_ready {
                                                send_channel_ready!(channel_state.short_to_chan_info, channel_state.pending_msg_events, chan.get(), msg);
@@ -4687,13 +4701,12 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
 
                                        // Update the monitor with the shutdown script if necessary.
                                        if let Some(monitor_update) = monitor_update {
-                                               if let Err(e) = self.chain_monitor.update_channel(chan_entry.get().get_funding_txo().unwrap(), monitor_update) {
-                                                       let (result, is_permanent) =
-                                                               handle_monitor_err!(self, e, channel_state.short_to_chan_info, chan_entry.get_mut(), RAACommitmentOrder::CommitmentFirst, chan_entry.key(), NO_UPDATE);
-                                                       if is_permanent {
-                                                               remove_channel!(self, channel_state, chan_entry);
-                                                               break result;
-                                                       }
+                                               let update_res = self.chain_monitor.update_channel(chan_entry.get().get_funding_txo().unwrap(), monitor_update);
+                                               let (result, is_permanent) =
+                                                       handle_monitor_update_res!(self, update_res, channel_state.short_to_chan_info, chan_entry.get_mut(), RAACommitmentOrder::CommitmentFirst, chan_entry.key(), NO_UPDATE);
+                                               if is_permanent {
+                                                       remove_channel!(self, channel_state, chan_entry);
+                                                       break result;
                                                }
                                        }
 
@@ -4782,7 +4795,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        return Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
                                }
 
-                               let create_pending_htlc_status = |chan: &Channel<Signer>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
+                               let create_pending_htlc_status = |chan: &Channel<<K::Target as KeysInterface>::Signer>, pending_forward_info: PendingHTLCStatus, error_code: u16| {
                                        // If the update_add is completely bogus, the call will Err and we will close,
                                        // but if we've sent a shutdown and they haven't acknowledged it yet, we just
                                        // want to reject the new HTLC and fail it backwards instead of forwarding.
@@ -4882,9 +4895,11 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                },
                                                Ok(res) => res
                                        };
-                               if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update) {
-                                       return_monitor_err!(self, e, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some());
+                               let update_res = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), monitor_update);
+                               if let Err(e) = handle_monitor_update_res!(self, update_res, channel_state, chan, RAACommitmentOrder::RevokeAndACKFirst, true, commitment_signed.is_some()) {
+                                       return Err(e);
                                }
+
                                channel_state.pending_msg_events.push(events::MessageSendEvent::SendRevokeAndACK {
                                        node_id: counterparty_node_id.clone(),
                                        msg: revoke_and_ack,
@@ -4956,26 +4971,27 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                        if chan.get().get_counterparty_node_id() != *counterparty_node_id {
                                                break Err(MsgHandleErrInternal::send_err_msg_no_close("Got a message for a channel from the wrong node!".to_owned(), msg.channel_id));
                                        }
-                                       let was_frozen_for_monitor = chan.get().is_awaiting_monitor_update();
+                                       let was_paused_for_mon_update = chan.get().is_awaiting_monitor_update();
                                        let raa_updates = break_chan_entry!(self,
                                                chan.get_mut().revoke_and_ack(&msg, &self.logger), channel_state, chan);
                                        htlcs_to_fail = raa_updates.holding_cell_failed_htlcs;
-                                       if let Err(e) = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), raa_updates.monitor_update) {
-                                               if was_frozen_for_monitor {
-                                                       assert!(raa_updates.commitment_update.is_none());
-                                                       assert!(raa_updates.accepted_htlcs.is_empty());
-                                                       assert!(raa_updates.failed_htlcs.is_empty());
-                                                       assert!(raa_updates.finalized_claimed_htlcs.is_empty());
-                                                       break Err(MsgHandleErrInternal::ignore_no_close("Previous monitor update failure prevented responses to RAA".to_owned()));
-                                               } else {
-                                                       if let Err(e) = handle_monitor_err!(self, e, channel_state, chan,
-                                                                       RAACommitmentOrder::CommitmentFirst, false,
-                                                                       raa_updates.commitment_update.is_some(), false,
-                                                                       raa_updates.accepted_htlcs, raa_updates.failed_htlcs,
-                                                                       raa_updates.finalized_claimed_htlcs) {
-                                                               break Err(e);
-                                                       } else { unreachable!(); }
-                                               }
+                                       let update_res = self.chain_monitor.update_channel(chan.get().get_funding_txo().unwrap(), raa_updates.monitor_update);
+                                       if was_paused_for_mon_update {
+                                               assert!(update_res != ChannelMonitorUpdateStatus::Completed);
+                                               assert!(raa_updates.commitment_update.is_none());
+                                               assert!(raa_updates.accepted_htlcs.is_empty());
+                                               assert!(raa_updates.failed_htlcs.is_empty());
+                                               assert!(raa_updates.finalized_claimed_htlcs.is_empty());
+                                               break Err(MsgHandleErrInternal::ignore_no_close("Existing pending monitor update prevented responses to RAA".to_owned()));
+                                       }
+                                       if update_res != ChannelMonitorUpdateStatus::Completed {
+                                               if let Err(e) = handle_monitor_update_res!(self, update_res, channel_state, chan,
+                                                               RAACommitmentOrder::CommitmentFirst, false,
+                                                               raa_updates.commitment_update.is_some(), false,
+                                                               raa_updates.accepted_htlcs, raa_updates.failed_htlcs,
+                                                               raa_updates.finalized_claimed_htlcs) {
+                                                       break Err(e);
+                                               } else { unreachable!(); }
                                        }
                                        if let Some(updates) = raa_updates.commitment_update {
                                                channel_state.pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
@@ -5188,7 +5204,7 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                        });
                                                }
                                        },
-                                       MonitorEvent::UpdateCompleted { funding_txo, monitor_update_id } => {
+                                       MonitorEvent::Completed { funding_txo, monitor_update_id } => {
                                                self.channel_monitor_updated(&funding_txo, monitor_update_id);
                                        },
                                }
@@ -5240,16 +5256,19 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
                                                        ));
                                                }
                                                if let Some((commitment_update, monitor_update)) = commitment_opt {
-                                                       if let Err(e) = self.chain_monitor.update_channel(chan.get_funding_txo().unwrap(), monitor_update) {
-                                                               has_monitor_update = true;
-                                                               let (res, close_channel) = handle_monitor_err!(self, e, short_to_chan_info, chan, RAACommitmentOrder::CommitmentFirst, channel_id, COMMITMENT_UPDATE_ONLY);
-                                                               handle_errors.push((chan.get_counterparty_node_id(), res));
-                                                               if close_channel { return false; }
-                                                       } else {
-                                                               pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
-                                                                       node_id: chan.get_counterparty_node_id(),
-                                                                       updates: commitment_update,
-                                                               });
+                                                       match self.chain_monitor.update_channel(chan.get_funding_txo().unwrap(), monitor_update) {
+                                                               ChannelMonitorUpdateStatus::Completed => {
+                                                                       pending_msg_events.push(events::MessageSendEvent::UpdateHTLCs {
+                                                                               node_id: chan.get_counterparty_node_id(),
+                                                                               updates: commitment_update,
+                                                                       });
+                                                               },
+                                                               e => {
+                                                                       has_monitor_update = true;
+                                                                       let (res, close_channel) = handle_monitor_update_res!(self, e, short_to_chan_info, chan, RAACommitmentOrder::CommitmentFirst, channel_id, COMMITMENT_UPDATE_ONLY);
+                                                                       handle_errors.push((chan.get_counterparty_node_id(), res));
+                                                                       if close_channel { return false; }
+                                                               },
                                                        }
                                                }
                                                true
@@ -5549,10 +5568,10 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelMana
        }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> MessageSendEventsProvider for ChannelManager<Signer, M, T, K, F, L>
-       where M::Target: chain::Watch<Signer>,
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> MessageSendEventsProvider for ChannelManager<M, T, K, F, L>
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
                                L::Target: Logger,
 {
@@ -5588,11 +5607,11 @@ impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> MessageSend
        }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> EventsProvider for ChannelManager<Signer, M, T, K, F, L>
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> EventsProvider for ChannelManager<M, T, K, F, L>
 where
-       M::Target: chain::Watch<Signer>,
+       M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
        T::Target: BroadcasterInterface,
-       K::Target: KeysInterface<Signer = Signer>,
+       K::Target: KeysInterface,
        F::Target: FeeEstimator,
        L::Target: Logger,
 {
@@ -5624,11 +5643,11 @@ where
        }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Listen for ChannelManager<Signer, M, T, K, F, L>
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Listen for ChannelManager<M, T, K, F, L>
 where
-       M::Target: chain::Watch<Signer>,
+       M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
        T::Target: BroadcasterInterface,
-       K::Target: KeysInterface<Signer = Signer>,
+       K::Target: KeysInterface,
        F::Target: FeeEstimator,
        L::Target: Logger,
 {
@@ -5661,11 +5680,11 @@ where
        }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Confirm for ChannelManager<Signer, M, T, K, F, L>
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> chain::Confirm for ChannelManager<M, T, K, F, L>
 where
-       M::Target: chain::Watch<Signer>,
+       M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
        T::Target: BroadcasterInterface,
-       K::Target: KeysInterface<Signer = Signer>,
+       K::Target: KeysInterface,
        F::Target: FeeEstimator,
        L::Target: Logger,
 {
@@ -5763,18 +5782,18 @@ where
        }
 }
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<Signer, M, T, K, F, L>
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> ChannelManager<M, T, K, F, L>
 where
-       M::Target: chain::Watch<Signer>,
+       M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
        T::Target: BroadcasterInterface,
-       K::Target: KeysInterface<Signer = Signer>,
+       K::Target: KeysInterface,
        F::Target: FeeEstimator,
        L::Target: Logger,
 {
        /// Calls a function which handles an on-chain event (blocks dis/connected, transactions
        /// un/confirmed, etc) on each channel, handling any resulting errors or messages generated by
        /// the function.
-       fn do_chain_event<FN: Fn(&mut Channel<Signer>) -> Result<(Option<msgs::ChannelReady>, Vec<(HTLCSource, PaymentHash)>, Option<msgs::AnnouncementSignatures>), ClosureReason>>
+       fn do_chain_event<FN: Fn(&mut Channel<<K::Target as KeysInterface>::Signer>) -> Result<(Option<msgs::ChannelReady>, Vec<(HTLCSource, PaymentHash)>, Option<msgs::AnnouncementSignatures>), ClosureReason>>
                        (&self, height_opt: Option<u32>, f: FN) {
                // Note that we MUST NOT end up calling methods on self.chain_monitor here - we're called
                // during initialization prior to the chain_monitor being fully configured in some cases.
@@ -5932,11 +5951,11 @@ where
        }
 }
 
-impl<Signer: Sign, M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
-       ChannelMessageHandler for ChannelManager<Signer, M, T, K, F, L>
-       where M::Target: chain::Watch<Signer>,
+impl<M: Deref , T: Deref , K: Deref , F: Deref , L: Deref >
+       ChannelMessageHandler for ChannelManager<M, T, K, F, L>
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
@@ -6409,7 +6428,7 @@ impl Writeable for ClaimableHTLC {
 
 impl Readable for ClaimableHTLC {
        fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
-               let mut prev_hop = ::util::ser::OptionDeserWrapper(None);
+               let mut prev_hop = crate::util::ser::OptionDeserWrapper(None);
                let mut value = 0;
                let mut payment_data: Option<msgs::FinalOnionHopData> = None;
                let mut cltv_expiry = 0;
@@ -6459,7 +6478,7 @@ impl Readable for HTLCSource {
                let id: u8 = Readable::read(reader)?;
                match id {
                        0 => {
-                               let mut session_priv: ::util::ser::OptionDeserWrapper<SecretKey> = ::util::ser::OptionDeserWrapper(None);
+                               let mut session_priv: crate::util::ser::OptionDeserWrapper<SecretKey> = crate::util::ser::OptionDeserWrapper(None);
                                let mut first_hop_htlc_msat: u64 = 0;
                                let mut path = Some(Vec::new());
                                let mut payment_id = None;
@@ -6480,7 +6499,7 @@ impl Readable for HTLCSource {
                                }
                                Ok(HTLCSource::OutboundRoute {
                                        session_priv: session_priv.0.unwrap(),
-                                       first_hop_htlc_msat: first_hop_htlc_msat,
+                                       first_hop_htlc_msat,
                                        path: path.unwrap(),
                                        payment_id: payment_id.unwrap(),
                                        payment_secret,
@@ -6494,7 +6513,7 @@ impl Readable for HTLCSource {
 }
 
 impl Writeable for HTLCSource {
-       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::io::Error> {
+       fn write<W: Writer>(&self, writer: &mut W) -> Result<(), crate::io::Error> {
                match self {
                        HTLCSource::OutboundRoute { ref session_priv, ref first_hop_htlc_msat, ref path, payment_id, payment_secret, payment_params } => {
                                0u8.write(writer)?;
@@ -6571,10 +6590,10 @@ impl_writeable_tlv_based_enum_upgradable!(PendingOutboundPayment,
        },
 );
 
-impl<Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<Signer, M, T, K, F, L>
-       where M::Target: chain::Watch<Signer>,
+impl<M: Deref, T: Deref, K: Deref, F: Deref, L: Deref> Writeable for ChannelManager<M, T, K, F, L>
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
@@ -6820,29 +6839,29 @@ impl<'a, Signer: 'a + Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
 
 // Implement ReadableArgs for an Arc'd ChannelManager to make it a bit easier to work with the
 // SipmleArcChannelManager type:
-impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
-       ReadableArgs<ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<Signer, M, T, K, F, L>>)
-       where M::Target: chain::Watch<Signer>,
+impl<'a, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
+       ReadableArgs<ChannelManagerReadArgs<'a, <K::Target as KeysInterface>::Signer, M, T, K, F, L>> for (BlockHash, Arc<ChannelManager<M, T, K, F, L>>)
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       fn read<R: io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
-               let (blockhash, chan_manager) = <(BlockHash, ChannelManager<Signer, M, T, K, F, L>)>::read(reader, args)?;
+       fn read<R: io::Read>(reader: &mut R, args: ChannelManagerReadArgs<'a, <K::Target as KeysInterface>::Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
+               let (blockhash, chan_manager) = <(BlockHash, ChannelManager<M, T, K, F, L>)>::read(reader, args)?;
                Ok((blockhash, Arc::new(chan_manager)))
        }
 }
 
-impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
-       ReadableArgs<ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>> for (BlockHash, ChannelManager<Signer, M, T, K, F, L>)
-       where M::Target: chain::Watch<Signer>,
+impl<'a, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
+       ReadableArgs<ChannelManagerReadArgs<'a, <K::Target as KeysInterface>::Signer, M, T, K, F, L>> for (BlockHash, ChannelManager<M, T, K, F, L>)
+       where M::Target: chain::Watch<<K::Target as KeysInterface>::Signer>,
         T::Target: BroadcasterInterface,
-        K::Target: KeysInterface<Signer = Signer>,
+        K::Target: KeysInterface,
         F::Target: FeeEstimator,
         L::Target: Logger,
 {
-       fn read<R: io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
+       fn read<R: io::Read>(reader: &mut R, mut args: ChannelManagerReadArgs<'a, <K::Target as KeysInterface>::Signer, M, T, K, F, L>) -> Result<Self, DecodeError> {
                let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
 
                let genesis_hash: BlockHash = Readable::read(reader)?;
@@ -6858,7 +6877,7 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                let mut short_to_chan_info = HashMap::with_capacity(cmp::min(channel_count as usize, 128));
                let mut channel_closures = Vec::new();
                for _ in 0..channel_count {
-                       let mut channel: Channel<Signer> = Channel::read(reader, (&args.keys_manager, best_block_height))?;
+                       let mut channel: Channel<<K::Target as KeysInterface>::Signer> = Channel::read(reader, (&args.keys_manager, best_block_height))?;
                        let funding_txo = channel.get_funding_txo().ok_or(DecodeError::InvalidValue)?;
                        funding_txo_set.insert(funding_txo.clone());
                        if let Some(ref mut monitor) = args.channel_monitors.get_mut(&funding_txo) {
@@ -6902,6 +6921,16 @@ impl<'a, Signer: Sign, M: Deref, T: Deref, K: Deref, F: Deref, L: Deref>
                                        }
                                        by_id.insert(channel.channel_id(), channel);
                                }
+                       } else if channel.is_awaiting_initial_mon_persist() {
+                               // If we were persisted and shut down while the initial ChannelMonitor persistence
+                               // was in-progress, we never broadcasted the funding transaction and can still
+                               // safely discard the channel.
+                               let _ = channel.force_shutdown(false);
+                               channel_closures.push(events::Event::ChannelClosed {
+                                       channel_id: channel.channel_id(),
+                                       user_channel_id: channel.get_user_id(),
+                                       reason: ClosureReason::DisconnectedPeer,
+                               });
                        } else {
                                log_error!(args.logger, "Missing ChannelMonitor for channel {} needed by ChannelManager.", log_bytes!(channel.channel_id()));
                                log_error!(args.logger, " The chain::Watch API *requires* that monitors are persisted durably before returning,");
@@ -7276,16 +7305,16 @@ mod tests {
        use bitcoin::hashes::sha256::Hash as Sha256;
        use core::time::Duration;
        use core::sync::atomic::Ordering;
-       use ln::{PaymentPreimage, PaymentHash, PaymentSecret};
-       use ln::channelmanager::{self, inbound_payment, PaymentId, PaymentSendFailure};
-       use ln::functional_test_utils::*;
-       use ln::msgs;
-       use ln::msgs::ChannelMessageHandler;
-       use routing::router::{PaymentParameters, RouteParameters, find_route};
-       use util::errors::APIError;
-       use util::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
-       use util::test_utils;
-       use chain::keysinterface::KeysInterface;
+       use crate::ln::{PaymentPreimage, PaymentHash, PaymentSecret};
+       use crate::ln::channelmanager::{self, inbound_payment, PaymentId, PaymentSendFailure};
+       use crate::ln::functional_test_utils::*;
+       use crate::ln::msgs;
+       use crate::ln::msgs::ChannelMessageHandler;
+       use crate::routing::router::{PaymentParameters, RouteParameters, find_route};
+       use crate::util::errors::APIError;
+       use crate::util::events::{Event, HTLCDestination, MessageSendEvent, MessageSendEventsProvider, ClosureReason};
+       use crate::util::test_utils;
+       use crate::chain::keysinterface::KeysInterface;
 
        #[test]
        fn test_notify_limits() {
@@ -7843,34 +7872,33 @@ mod tests {
 
 #[cfg(all(any(test, feature = "_test_utils"), feature = "_bench_unstable"))]
 pub mod bench {
-       use chain::Listen;
-       use chain::chainmonitor::{ChainMonitor, Persist};
-       use chain::keysinterface::{KeysManager, KeysInterface, InMemorySigner};
-       use ln::channelmanager::{self, BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage};
-       use ln::features::{InitFeatures, InvoiceFeatures};
-       use ln::functional_test_utils::*;
-       use ln::msgs::{ChannelMessageHandler, Init};
-       use routing::gossip::NetworkGraph;
-       use routing::router::{PaymentParameters, get_route};
-       use util::test_utils;
-       use util::config::UserConfig;
-       use util::events::{Event, MessageSendEvent, MessageSendEventsProvider};
+       use crate::chain::Listen;
+       use crate::chain::chainmonitor::{ChainMonitor, Persist};
+       use crate::chain::keysinterface::{KeysManager, KeysInterface, InMemorySigner};
+       use crate::ln::channelmanager::{self, BestBlock, ChainParameters, ChannelManager, PaymentHash, PaymentPreimage};
+       use crate::ln::functional_test_utils::*;
+       use crate::ln::msgs::{ChannelMessageHandler, Init};
+       use crate::routing::gossip::NetworkGraph;
+       use crate::routing::router::{PaymentParameters, get_route};
+       use crate::util::test_utils;
+       use crate::util::config::UserConfig;
+       use crate::util::events::{Event, MessageSendEvent, MessageSendEventsProvider};
 
        use bitcoin::hashes::Hash;
        use bitcoin::hashes::sha256::Hash as Sha256;
        use bitcoin::{Block, BlockHeader, PackedLockTime, Transaction, TxMerkleNode, TxOut};
 
-       use sync::{Arc, Mutex};
+       use crate::sync::{Arc, Mutex};
 
        use test::Bencher;
 
        struct NodeHolder<'a, P: Persist<InMemorySigner>> {
-               node: &'a ChannelManager<InMemorySigner,
+               node: &'a ChannelManager<
                        &'a ChainMonitor<InMemorySigner, &'a test_utils::TestChainSource,
                                &'a test_utils::TestBroadcaster, &'a test_utils::TestFeeEstimator,
                                &'a test_utils::TestLogger, &'a P>,
                        &'a test_utils::TestBroadcaster, &'a KeysManager,
-                       &'a test_utils::TestFeeEstimator, &'a test_utils::TestLogger>
+                       &'a test_utils::TestFeeEstimator, &'a test_utils::TestLogger>,
        }
 
        #[cfg(test)]