X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fln%2Fchannel.rs;h=47936ea61d1b18bcfc69f76a9a32db125e6f3ed8;hb=95830edac76531fe20f9177eca532e9d73de5179;hp=dece3649e5e89d27c361eb3985be459c8234b7ad;hpb=8c69bb11b8e6c53f69e9a27f6657d69bee1b7e5e;p=rust-lightning

diff --git a/lightning/src/ln/channel.rs b/lightning/src/ln/channel.rs
index dece3649..47936ea6 100644
--- a/lightning/src/ln/channel.rs
+++ b/lightning/src/ln/channel.rs
@@ -35,6 +35,7 @@ use std;
 use std::default::Default;
 use std::{cmp,mem,fmt};
 use std::sync::{Arc};
+use std::ops::Deref;
 
 #[cfg(test)]
 pub struct ChannelValueStat {
@@ -247,6 +248,7 @@ pub(super) struct Channel<ChanSigner: ChannelKeys> {
 	#[cfg(test)]
 	pub(super) local_keys: ChanSigner,
 	shutdown_pubkey: PublicKey,
+	destination_script: Script,
 
 	// Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
 	// generation start at 0 and count up...this simplifies some parts of implementation at the
@@ -293,7 +295,7 @@ pub(super) struct Channel<ChanSigner: ChannelKeys> {
 	holding_cell_update_fee: Option<u64>,
 	next_local_htlc_id: u64,
 	next_remote_htlc_id: u64,
-	channel_update_count: u32,
+	update_time_counter: u32,
 	feerate_per_kw: u64,
 
 	#[cfg(debug_assertions)]
@@ -351,7 +353,9 @@ pub(super) struct Channel<ChanSigner: ChannelKeys> {
 
 	their_shutdown_scriptpubkey: Option<Script>,
 
-	channel_monitor: ChannelMonitor<ChanSigner>,
+	/// Used exclusively to broadcast the latest local state, mostly a historical quirk that this
+	/// is here:
+	channel_monitor: Option<ChannelMonitor<ChanSigner>>,
 	commitment_secrets: CounterpartyCommitmentSecrets,
 
 	network_sync: UpdateStatus,
@@ -383,16 +387,16 @@ pub const MAX_FUNDING_SATOSHIS: u64 = (1 << 24);
 /// Used to return a simple Error back to ChannelManager. Will get converted to a
 /// msgs::ErrorAction::SendErrorMessage or msgs::ErrorAction::IgnoreError as appropriate with our
 /// channel_id in ChannelManager.
-pub(super) enum ChannelError<ChanSigner: ChannelKeys> {
+pub(super) enum ChannelError {
 	Ignore(&'static str),
 	Close(&'static str),
 	CloseDelayBroadcast {
 		msg: &'static str,
-		update: Option<ChannelMonitor<ChanSigner>>,
+		update: ChannelMonitorUpdate,
 	},
 }
 
-impl<ChanSigner: ChannelKeys> fmt::Debug for ChannelError<ChanSigner> {
+impl fmt::Debug for ChannelError {
 	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
 		match self {
 			&ChannelError::Ignore(e) => write!(f, "Ignore : {}", e),
@@ -429,12 +433,11 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		cmp::max(at_open_background_feerate * B_OUTPUT_PLUS_SPENDING_INPUT_WEIGHT / 1000, 546) //TODO
 	}
 
-	fn derive_our_htlc_minimum_msat(_at_open_channel_feerate_per_kw: u64) -> u64 {
-		1000 // TODO
-	}
-
 	// Constructors:
-	pub fn new_outbound(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface<ChanKeySigner = ChanSigner>>, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel<ChanSigner>, APIError> {
+	pub fn new_outbound<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, their_node_id: PublicKey, channel_value_satoshis: u64, push_msat: u64, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel<ChanSigner>, APIError>
+	where K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
+	      F::Target: FeeEstimator,
+	{
 		let chan_keys = keys_provider.get_channel_keys(false, channel_value_satoshis);
 
 		if channel_value_satoshis >= MAX_FUNDING_SATOSHIS {
@@ -456,12 +459,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 		let feerate = fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Normal);
 
-		let secp_ctx = Secp256k1::new();
-		let channel_monitor = ChannelMonitor::new(chan_keys.clone(),
-		                                          chan_keys.funding_key(), chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(),
-		                                          chan_keys.htlc_base_key(), chan_keys.payment_base_key(), &keys_provider.get_shutdown_pubkey(), config.own_channel_config.our_to_self_delay,
-		                                          keys_provider.get_destination_script(), logger.clone());
-
 		Ok(Channel {
 			user_id: user_id,
 			config: config.channel_options.clone(),
@@ -469,13 +466,15 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			channel_id: keys_provider.get_channel_id(),
 			channel_state: ChannelState::OurInitSent as u32,
 			channel_outbound: true,
-			secp_ctx: secp_ctx,
+			secp_ctx: Secp256k1::new(),
 			channel_value_satoshis: channel_value_satoshis,
 
 			latest_monitor_update_id: 0,
 
 			local_keys: chan_keys,
 			shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
+			destination_script: keys_provider.get_destination_script(),
+
 			cur_local_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 			cur_remote_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 			value_to_self_msat: channel_value_satoshis * 1000 - push_msat,
@@ -487,7 +486,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			holding_cell_update_fee: None,
 			next_local_htlc_id: 0,
 			next_remote_htlc_id: 0,
-			channel_update_count: 1,
+			update_time_counter: 1,
 
 			resend_order: RAACommitmentOrder::CommitmentFirst,
 
@@ -516,7 +515,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			their_max_htlc_value_in_flight_msat: 0,
 			their_channel_reserve_satoshis: 0,
 			their_htlc_minimum_msat: 0,
-			our_htlc_minimum_msat: Channel::<ChanSigner>::derive_our_htlc_minimum_msat(feerate),
+			our_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 			their_to_self_delay: 0,
 			our_to_self_delay: config.own_channel_config.our_to_self_delay,
 			their_max_accepted_htlcs: 0,
@@ -530,7 +529,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 			their_shutdown_scriptpubkey: None,
 
-			channel_monitor: channel_monitor,
+			channel_monitor: None,
 			commitment_secrets: CounterpartyCommitmentSecrets::new(),
 
 			network_sync: UpdateStatus::Fresh,
@@ -539,7 +538,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		})
 	}
 
-	fn check_remote_fee(fee_estimator: &FeeEstimator, feerate_per_kw: u32) -> Result<(), ChannelError<ChanSigner>> {
+	fn check_remote_fee<F: Deref>(fee_estimator: &F, feerate_per_kw: u32) -> Result<(), ChannelError>
+		where F::Target: FeeEstimator
+	{
 		if (feerate_per_kw as u64) < fee_estimator.get_est_sat_per_1000_weight(ConfirmationTarget::Background) {
 			return Err(ChannelError::Close("Peer's feerate much too low"));
 		}
@@ -551,7 +552,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	/// Creates a new channel from a remote sides' request for one.
 	/// Assumes chain_hash has already been checked and corresponds with what we expect!
-	pub fn new_from_req(fee_estimator: &FeeEstimator, keys_provider: &Arc<KeysInterface<ChanKeySigner = ChanSigner>>, their_node_id: PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel<ChanSigner>, ChannelError<ChanSigner>> {
+	pub fn new_from_req<K: Deref, F: Deref>(fee_estimator: &F, keys_provider: &K, their_node_id: PublicKey, their_features: InitFeatures, msg: &msgs::OpenChannel, user_id: u64, logger: Arc<Logger>, config: &UserConfig) -> Result<Channel<ChanSigner>, ChannelError>
+		where K::Target: KeysInterface<ChanKeySigner = ChanSigner>,
+          F::Target: FeeEstimator
+	{
 		let mut chan_keys = keys_provider.get_channel_keys(true, msg.funding_satoshis);
 		let their_pubkeys = ChannelPublicKeys {
 			funding_pubkey: msg.funding_pubkey,
@@ -659,12 +663,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			return Err(ChannelError::Close("Insufficient funding amount for initial commitment"));
 		}
 
-		let secp_ctx = Secp256k1::new();
-		let channel_monitor = ChannelMonitor::new(chan_keys.clone(),
-		                                          chan_keys.funding_key(), chan_keys.revocation_base_key(), chan_keys.delayed_payment_base_key(),
-		                                          chan_keys.htlc_base_key(), chan_keys.payment_base_key(), &keys_provider.get_shutdown_pubkey(), config.own_channel_config.our_to_self_delay,
-		                                          keys_provider.get_destination_script(), logger.clone());
-
 		let their_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
 			match &msg.shutdown_scriptpubkey {
 				&OptionalField::Present(ref script) => {
@@ -686,19 +684,21 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			}
 		} else { None };
 
-		let mut chan = Channel {
+		let chan = Channel {
 			user_id: user_id,
 			config: local_config,
 
 			channel_id: msg.temporary_channel_id,
 			channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
 			channel_outbound: false,
-			secp_ctx: secp_ctx,
+			secp_ctx: Secp256k1::new(),
 
 			latest_monitor_update_id: 0,
 
 			local_keys: chan_keys,
 			shutdown_pubkey: keys_provider.get_shutdown_pubkey(),
+			destination_script: keys_provider.get_destination_script(),
+
 			cur_local_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 			cur_remote_commitment_transaction_number: INITIAL_COMMITMENT_NUMBER,
 			value_to_self_msat: msg.push_msat,
@@ -710,7 +710,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			holding_cell_update_fee: None,
 			next_local_htlc_id: 0,
 			next_remote_htlc_id: 0,
-			channel_update_count: 1,
+			update_time_counter: 1,
 
 			resend_order: RAACommitmentOrder::CommitmentFirst,
 
@@ -740,7 +740,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			their_max_htlc_value_in_flight_msat: cmp::min(msg.max_htlc_value_in_flight_msat, msg.funding_satoshis * 1000),
 			their_channel_reserve_satoshis: msg.channel_reserve_satoshis,
 			their_htlc_minimum_msat: msg.htlc_minimum_msat,
-			our_htlc_minimum_msat: Channel::<ChanSigner>::derive_our_htlc_minimum_msat(msg.feerate_per_kw as u64),
+			our_htlc_minimum_msat: if config.own_channel_config.our_htlc_minimum_msat == 0 { 1 } else { config.own_channel_config.our_htlc_minimum_msat },
 			their_to_self_delay: msg.to_self_delay,
 			our_to_self_delay: config.own_channel_config.our_to_self_delay,
 			their_max_accepted_htlcs: msg.max_accepted_htlcs,
@@ -754,7 +754,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 			their_shutdown_scriptpubkey,
 
-			channel_monitor: channel_monitor,
+			channel_monitor: None,
 			commitment_secrets: CounterpartyCommitmentSecrets::new(),
 
 			network_sync: UpdateStatus::Fresh,
@@ -762,10 +762,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			logger,
 		};
 
-		let obscure_factor = chan.get_commitment_transaction_number_obscure_factor();
-		let funding_redeemscript = chan.get_funding_redeemscript();
-		chan.channel_monitor.set_basic_channel_info(&msg.htlc_basepoint, &msg.delayed_payment_basepoint, msg.to_self_delay, funding_redeemscript, msg.funding_satoshis, obscure_factor);
-
 		Ok(chan)
 	}
 
@@ -1102,7 +1098,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// our counterparty!)
 	/// The result is a transaction which we can revoke ownership of (ie a "local" transaction)
 	/// TODO Some magic rust shit to compile-time check this?
-	fn build_local_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError<ChanSigner>> {
+	fn build_local_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
 		let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(commitment_number));
 		let delayed_payment_base = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.delayed_payment_base_key());
 		let htlc_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.htlc_base_key());
@@ -1115,7 +1111,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// Creates a set of keys for build_commitment_transaction to generate a transaction which we
 	/// will sign and send to our counterparty.
 	/// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
-	fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError<ChanSigner>> {
+	fn build_remote_transaction_keys(&self) -> Result<TxCreationKeys, ChannelError> {
 		//TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
 		//may see payments to it!
 		let payment_basepoint = PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.payment_base_key());
@@ -1142,9 +1138,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	}
 
 	/// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
-	/// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
-	/// Ok(_) if debug assertions are turned on and preconditions are met.
-	fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitor<ChanSigner>>), ChannelError<ChanSigner>> {
+	/// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
+	/// return Ok(_) if debug assertions are turned on or preconditions are met.
+	///
+	/// Note that it is still possible to hit these assertions in case we find a preimage on-chain
+	/// but then have a reorg which settles on an HTLC-failure on chain.
+	fn get_update_fulfill_htlc(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage) -> Result<(Option<msgs::UpdateFulfillHTLC>, Option<ChannelMonitorUpdate>), ChannelError> {
 		// Either ChannelFunded got set (which means it won't be unset) or there is no way any
 		// caller thought we could have something claimed (cause we wouldn't have accepted in an
 		// incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
@@ -1171,6 +1170,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						} else {
 							log_warn!(self, "Have preimage and want to fulfill HTLC with payment hash {} we already failed against channel {}", log_bytes!(htlc.payment_hash.0), log_bytes!(self.channel_id()));
 						}
+						debug_assert!(false, "Tried to fulfill an HTLC that was already fail/fulfilled");
 						return Ok((None, None));
 					},
 					_ => {
@@ -1190,13 +1190,23 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		//
 		// We have to put the payment_preimage in the channel_monitor right away here to ensure we
 		// can claim it even if the channel hits the chain before we see their next commitment.
-		self.channel_monitor.provide_payment_preimage(&payment_hash_calc, &payment_preimage_arg);
+		self.latest_monitor_update_id += 1;
+		let monitor_update = ChannelMonitorUpdate {
+			update_id: self.latest_monitor_update_id,
+			updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
+				payment_preimage: payment_preimage_arg.clone(),
+			}],
+		};
+		self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
 
 		if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateFailed as u32)) != 0 {
 			for pending_update in self.holding_cell_htlc_updates.iter() {
 				match pending_update {
 					&HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
 						if htlc_id_arg == htlc_id {
+							// Make sure we don't leave latest_monitor_update_id incremented here:
+							self.latest_monitor_update_id -= 1;
+							debug_assert!(false, "Tried to fulfill an HTLC that was already fulfilled");
 							return Ok((None, None));
 						}
 					},
@@ -1205,7 +1215,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 							log_warn!(self, "Have preimage and want to fulfill HTLC with pending failure against channel {}", log_bytes!(self.channel_id()));
 							// TODO: We may actually be able to switch to a fulfill here, though its
 							// rare enough it may not be worth the complexity burden.
-							return Ok((None, Some(self.channel_monitor.clone())));
+							debug_assert!(false, "Tried to fulfill an HTLC that was already failed");
+							return Ok((None, Some(monitor_update)));
 						}
 					},
 					_ => {}
@@ -1215,7 +1226,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			self.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
 				payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
 			});
-			return Ok((None, Some(self.channel_monitor.clone())));
+			return Ok((None, Some(monitor_update)));
 		}
 
 		{
@@ -1223,7 +1234,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			if let InboundHTLCState::Committed = htlc.state {
 			} else {
 				debug_assert!(false, "Have an inbound HTLC we tried to claim before it was fully committed to");
-				return Ok((None, Some(self.channel_monitor.clone())));
+				return Ok((None, Some(monitor_update)));
 			}
 			log_trace!(self, "Upgrading HTLC {} to LocalRemoved with a Fulfill!", log_bytes!(htlc.payment_hash.0));
 			htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(payment_preimage_arg.clone()));
@@ -1233,24 +1244,35 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			channel_id: self.channel_id(),
 			htlc_id: htlc_id_arg,
 			payment_preimage: payment_preimage_arg,
-		}), Some(self.channel_monitor.clone())))
+		}), Some(monitor_update)))
 	}
 
-	pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitor<ChanSigner>>), ChannelError<ChanSigner>> {
+	pub fn get_update_fulfill_htlc_and_commit(&mut self, htlc_id: u64, payment_preimage: PaymentPreimage) -> Result<(Option<(msgs::UpdateFulfillHTLC, msgs::CommitmentSigned)>, Option<ChannelMonitorUpdate>), ChannelError> {
 		match self.get_update_fulfill_htlc(htlc_id, payment_preimage)? {
-			(Some(update_fulfill_htlc), _) => {
+			(Some(update_fulfill_htlc), Some(mut monitor_update)) => {
+				let (commitment, mut additional_update) = self.send_commitment_no_status_check()?;
+				// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
+				// strictly increasing by one, so decrement it here.
+				self.latest_monitor_update_id = monitor_update.update_id;
+				monitor_update.updates.append(&mut additional_update.updates);
+				Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
+			},
+			(Some(update_fulfill_htlc), None) => {
 				let (commitment, monitor_update) = self.send_commitment_no_status_check()?;
 				Ok((Some((update_fulfill_htlc, commitment)), Some(monitor_update)))
 			},
-			(None, Some(channel_monitor)) => Ok((None, Some(channel_monitor))),
+			(None, Some(monitor_update)) => Ok((None, Some(monitor_update))),
 			(None, None) => Ok((None, None))
 		}
 	}
 
 	/// Per HTLC, only one get_update_fail_htlc or get_update_fulfill_htlc call may be made.
-	/// In such cases we debug_assert!(false) and return an IgnoreError. Thus, will always return
-	/// Ok(_) if debug assertions are turned on and preconditions are met.
-	pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError<ChanSigner>> {
+	/// In such cases we debug_assert!(false) and return a ChannelError::Ignore. Thus, will always
+	/// return Ok(_) if debug assertions are turned on or preconditions are met.
+	///
+	/// Note that it is still possible to hit these assertions in case we find a preimage on-chain
+	/// but then have a reorg which settles on an HTLC-failure on chain.
+	pub fn get_update_fail_htlc(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			panic!("Was asked to fail an HTLC when channel was not in an operational state");
 		}
@@ -1266,6 +1288,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				match htlc.state {
 					InboundHTLCState::Committed => {},
 					InboundHTLCState::LocalRemoved(_) => {
+						debug_assert!(false, "Tried to fail an HTLC that was already fail/fulfilled");
 						return Ok(None);
 					},
 					_ => {
@@ -1286,11 +1309,13 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				match pending_update {
 					&HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
 						if htlc_id_arg == htlc_id {
+							debug_assert!(false, "Tried to fail an HTLC that was already fulfilled");
 							return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
 						}
 					},
 					&HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
 						if htlc_id_arg == htlc_id {
+							debug_assert!(false, "Tried to fail an HTLC that was already failed");
 							return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID"));
 						}
 					},
@@ -1318,7 +1343,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	// Message handlers:
 
-	pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, config: &UserConfig, their_features: InitFeatures) -> Result<(), ChannelError> {
 		// Check sanity of message fields:
 		if !self.channel_outbound {
 			return Err(ChannelError::Close("Got an accept_channel message from an inbound peer"));
@@ -1420,16 +1445,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		self.their_cur_commitment_point = Some(msg.first_per_commitment_point);
 		self.their_shutdown_scriptpubkey = their_shutdown_scriptpubkey;
 
-		let obscure_factor = self.get_commitment_transaction_number_obscure_factor();
-		let funding_redeemscript = self.get_funding_redeemscript();
-		self.channel_monitor.set_basic_channel_info(&msg.htlc_basepoint, &msg.delayed_payment_basepoint, msg.to_self_delay, funding_redeemscript, self.channel_value_satoshis, obscure_factor);
-
 		self.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
 
 		Ok(())
 	}
 
-	fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, LocalCommitmentTransaction, Signature, TxCreationKeys), ChannelError<ChanSigner>> {
+	fn funding_created_signature(&mut self, sig: &Signature) -> Result<(Transaction, LocalCommitmentTransaction, Signature, TxCreationKeys), ChannelError> {
 		let funding_script = self.get_funding_redeemscript();
 
 		let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
@@ -1454,7 +1475,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		&self.their_pubkeys.as_ref().expect("their_funding_pubkey() only allowed after accept_channel").funding_pubkey
 	}
 
-	pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	pub fn funding_created(&mut self, msg: &msgs::FundingCreated) -> Result<(msgs::FundingSigned, ChannelMonitor<ChanSigner>), ChannelError> {
 		if self.channel_outbound {
 			return Err(ChannelError::Close("Received funding_created for an outbound channel?"));
 		}
@@ -1481,13 +1502,30 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			}
 		};
 
-		let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
-		self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
-
 		// Now that we're past error-generating stuff, update our local state:
 
-		self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_initial_commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
-		self.channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx, local_keys, self.feerate_per_kw, Vec::new()).unwrap();
+		let their_pubkeys = self.their_pubkeys.as_ref().unwrap();
+		let funding_redeemscript = self.get_funding_redeemscript();
+		let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+		macro_rules! create_monitor {
+			() => { {
+				let mut channel_monitor = ChannelMonitor::new(self.local_keys.clone(),
+				                                              &self.shutdown_pubkey, self.our_to_self_delay,
+				                                              &self.destination_script, (funding_txo, funding_txo_script.clone()),
+				                                              &their_pubkeys.htlc_basepoint, &their_pubkeys.delayed_payment_basepoint,
+				                                              self.their_to_self_delay, funding_redeemscript.clone(), self.channel_value_satoshis,
+				                                              self.get_commitment_transaction_number_obscure_factor(),
+				                                              self.logger.clone());
+
+				channel_monitor.provide_latest_remote_commitment_tx_info(&remote_initial_commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
+				channel_monitor.provide_latest_local_commitment_tx_info(local_initial_commitment_tx.clone(), local_keys.clone(), self.feerate_per_kw, Vec::new()).unwrap();
+				channel_monitor
+			} }
+		}
+
+		self.channel_monitor = Some(create_monitor!());
+		let channel_monitor = create_monitor!();
+
 		self.channel_state = ChannelState::FundingSent as u32;
 		self.channel_id = funding_txo.to_channel_id();
 		self.cur_remote_commitment_transaction_number -= 1;
@@ -1496,17 +1534,17 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		Ok((msgs::FundingSigned {
 			channel_id: self.channel_id,
 			signature: our_signature
-		}, self.channel_monitor.clone()))
+		}, channel_monitor))
 	}
 
 	/// Handles a funding_signed message from the remote end.
 	/// If this call is successful, broadcast the funding transaction (and not before!)
-	pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result<ChannelMonitorUpdate, ChannelError<ChanSigner>> {
+	pub fn funding_signed(&mut self, msg: &msgs::FundingSigned) -> Result<ChannelMonitorUpdate, (Option<ChannelMonitorUpdate>, ChannelError)> {
 		if !self.channel_outbound {
-			return Err(ChannelError::Close("Received funding_signed for an inbound channel?"));
+			return Err((None, ChannelError::Close("Received funding_signed for an inbound channel?")));
 		}
 		if self.channel_state & !(ChannelState::MonitorUpdateFailed as u32) != ChannelState::FundingCreated as u32 {
-			return Err(ChannelError::Close("Received funding_signed in strange state!"));
+			return Err((None, ChannelError::Close("Received funding_signed in strange state!")));
 		}
 		if self.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
 				self.cur_remote_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER - 1 ||
@@ -1516,14 +1554,16 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 		let funding_script = self.get_funding_redeemscript();
 
-		let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
+		let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number).map_err(|e| (None, e))?;
 		let local_initial_commitment_tx = self.build_commitment_transaction(self.cur_local_commitment_transaction_number, &local_keys, true, false, self.feerate_per_kw).0;
 		let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_initial_commitment_tx).sighash_all(&local_initial_commitment_tx.input[0], &funding_script, self.channel_value_satoshis)[..]);
 
 		let their_funding_pubkey = &self.their_pubkeys.as_ref().unwrap().funding_pubkey;
 
 		// They sign the "local" commitment transaction, allowing us to broadcast the tx if we wish.
-		secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, their_funding_pubkey), "Invalid funding_signed signature from peer");
+		if let Err(_) = self.secp_ctx.verify(&local_sighash, &msg.signature, their_funding_pubkey) {
+			return Err((None, ChannelError::Close("Invalid funding_signed signature from peer")));
+		}
 
 		self.latest_monitor_update_id += 1;
 		let monitor_update = ChannelMonitorUpdate {
@@ -1533,18 +1573,19 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				local_keys, feerate_per_kw: self.feerate_per_kw, htlc_outputs: Vec::new(),
 			}]
 		};
-		self.channel_monitor.update_monitor(monitor_update.clone()).unwrap();
+		self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
 		self.channel_state = ChannelState::FundingSent as u32 | (self.channel_state & (ChannelState::MonitorUpdateFailed as u32));
 		self.cur_local_commitment_transaction_number -= 1;
 
 		if self.channel_state & (ChannelState::MonitorUpdateFailed as u32) == 0 {
 			Ok(monitor_update)
 		} else {
-			Err(ChannelError::Ignore("Previous monitor update failure prevented funding_signed from allowing funding broadcast"))
+			Err((Some(monitor_update),
+				ChannelError::Ignore("Previous monitor update failure prevented funding_signed from allowing funding broadcast")))
 		}
 	}
 
-	pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn funding_locked(&mut self, msg: &msgs::FundingLocked) -> Result<(), ChannelError> {
 		if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
 			return Err(ChannelError::Close("Peer sent funding_locked when we needed a channel_reestablish"));
 		}
@@ -1555,7 +1596,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			self.channel_state |= ChannelState::TheirFundingLocked as u32;
 		} else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
 			self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
-			self.channel_update_count += 1;
+			self.update_time_counter += 1;
 		} else if (self.channel_state & (ChannelState::ChannelFunded as u32) != 0 &&
 				 // Note that funding_signed/funding_created will have decremented both by 1!
 				 self.cur_local_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
@@ -1615,7 +1656,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		cmp::min(self.value_to_self_msat as i64 - self.get_outbound_pending_htlc_stats().1 as i64, 0) as u64)
 	}
 
-	pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, pending_forward_state: PendingHTLCStatus) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn update_add_htlc(&mut self, msg: &msgs::UpdateAddHTLC, pending_forward_state: PendingHTLCStatus) -> Result<(), ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state"));
 		}
@@ -1625,6 +1666,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		if msg.amount_msat > self.channel_value_satoshis * 1000 {
 			return Err(ChannelError::Close("Remote side tried to send more than the total value of the channel"));
 		}
+		if msg.amount_msat == 0 {
+			return Err(ChannelError::Close("Remote side tried to send a 0-msat HTLC"));
+		}
 		if msg.amount_msat < self.our_htlc_minimum_msat {
 			return Err(ChannelError::Close("Remote side tried to send less than our minimum HTLC value"));
 		}
@@ -1689,7 +1733,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	/// Marks an outbound HTLC which we have received update_fail/fulfill/malformed
 	#[inline]
-	fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError<ChanSigner>> {
+	fn mark_outbound_htlc_removed(&mut self, htlc_id: u64, check_preimage: Option<PaymentHash>, fail_reason: Option<HTLCFailReason>) -> Result<&HTLCSource, ChannelError> {
 		for htlc in self.pending_outbound_htlcs.iter_mut() {
 			if htlc.htlc_id == htlc_id {
 				match check_preimage {
@@ -1714,7 +1758,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find"))
 	}
 
-	pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError<ChanSigner>> {
+	pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<HTLCSource, ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state"));
 		}
@@ -1726,7 +1770,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		self.mark_outbound_htlc_removed(msg.htlc_id, Some(payment_hash), None).map(|source| source.clone())
 	}
 
-	pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state"));
 		}
@@ -1738,7 +1782,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		Ok(())
 	}
 
-	pub fn update_fail_malformed_htlc<'a>(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn update_fail_malformed_htlc<'a>(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state"));
 		}
@@ -1750,20 +1794,20 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		Ok(())
 	}
 
-	pub fn commitment_signed(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &FeeEstimator) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	pub fn commitment_signed<F: Deref>(&mut self, msg: &msgs::CommitmentSigned, fee_estimator: &F) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)> where F::Target: FeeEstimator {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
-			return Err(ChannelError::Close("Got commitment signed message when channel was not in an operational state"));
+			return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state")));
 		}
 		if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
-			return Err(ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish"));
+			return Err((None, ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish")));
 		}
 		if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.last_sent_closing_fee.is_some() {
-			return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds"));
+			return Err((None, ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds")));
 		}
 
 		let funding_script = self.get_funding_redeemscript();
 
-		let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number)?;
+		let local_keys = self.build_local_transaction_keys(self.cur_local_commitment_transaction_number).map_err(|e| (None, e))?;
 
 		let mut update_fee = false;
 		let feerate_per_kw = if !self.channel_outbound && self.pending_update_fee.is_some() {
@@ -1781,7 +1825,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		let local_commitment_txid = local_commitment_tx.0.txid();
 		let local_sighash = hash_to_message!(&bip143::SighashComponents::new(&local_commitment_tx.0).sighash_all(&local_commitment_tx.0.input[0], &funding_script, self.channel_value_satoshis)[..]);
 		log_trace!(self, "Checking commitment tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.signature.serialize_compact()[..]), log_bytes!(self.their_funding_pubkey().serialize()), encode::serialize_hex(&local_commitment_tx.0), encode::serialize_hex(&funding_script));
-		secp_check!(self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey()), "Invalid commitment tx signature from peer");
+		if let Err(_) = self.secp_ctx.verify(&local_sighash, &msg.signature, &self.their_funding_pubkey()) {
+			return Err((None, ChannelError::Close("Invalid commitment tx signature from peer")));
+		}
 
 		//If channel fee was updated by funder confirm funder can afford the new fee rate when applied to the current local commitment transaction
 		if update_fee {
@@ -1789,12 +1835,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			let total_fee: u64 = feerate_per_kw as u64 * (COMMITMENT_TX_BASE_WEIGHT + (num_htlcs as u64) * COMMITMENT_TX_WEIGHT_PER_HTLC) / 1000;
 
 			if self.channel_value_satoshis - self.value_to_self_msat / 1000 < total_fee + self.their_channel_reserve_satoshis {
-				return Err(ChannelError::Close("Funding remote cannot afford proposed new fee"));
+				return Err((None, ChannelError::Close("Funding remote cannot afford proposed new fee")));
 			}
 		}
 
 		if msg.htlc_signatures.len() != local_commitment_tx.1 {
-			return Err(ChannelError::Close("Got wrong number of HTLC signatures from remote"));
+			return Err((None, ChannelError::Close("Got wrong number of HTLC signatures from remote")));
 		}
 
 		let mut htlcs_and_sigs = Vec::with_capacity(local_commitment_tx.2.len());
@@ -1804,7 +1850,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &local_keys);
 				log_trace!(self, "Checking HTLC tx signature {} by key {} against tx {} with redeemscript {}", log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(local_keys.b_htlc_key.serialize()), encode::serialize_hex(&htlc_tx), encode::serialize_hex(&htlc_redeemscript));
 				let htlc_sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
-				secp_check!(self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key), "Invalid HTLC tx signature from peer");
+				if let Err(_) = self.secp_ctx.verify(&htlc_sighash, &msg.htlc_signatures[idx], &local_keys.b_htlc_key) {
+					return Err((None, ChannelError::Close("Invalid HTLC tx signature from peer")));
+				}
 				htlcs_and_sigs.push((htlc, Some(msg.htlc_signatures[idx]), source));
 			} else {
 				htlcs_and_sigs.push((htlc, None, source));
@@ -1831,9 +1879,15 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 		let their_funding_pubkey = self.their_pubkeys.as_ref().unwrap().funding_pubkey;
 
-		self.channel_monitor.provide_latest_local_commitment_tx_info(
-			LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), &their_funding_pubkey),
-			local_keys, self.feerate_per_kw, htlcs_and_sigs).unwrap();
+		self.latest_monitor_update_id += 1;
+		let mut monitor_update = ChannelMonitorUpdate {
+			update_id: self.latest_monitor_update_id,
+			updates: vec![ChannelMonitorUpdateStep::LatestLocalCommitmentTXInfo {
+				commitment_tx: LocalCommitmentTransaction::new_missing_local_sig(local_commitment_tx.0, &msg.signature, &PublicKey::from_secret_key(&self.secp_ctx, self.local_keys.funding_key()), &their_funding_pubkey),
+				local_keys, feerate_per_kw: self.feerate_per_kw, htlc_outputs: htlcs_and_sigs
+			}]
+		};
+		self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
 
 		for htlc in self.pending_inbound_htlcs.iter_mut() {
 			let new_forward = if let &InboundHTLCState::RemoteAnnounced(ref forward_info) = &htlc.state {
@@ -1866,26 +1920,31 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				// If we were going to send a commitment_signed after the RAA, go ahead and do all
 				// the corresponding HTLC status updates so that get_last_commitment_update
 				// includes the right HTLCs.
-				// Note that this generates a monitor update that we ignore! This is OK since we
-				// won't actually send the commitment_signed that generated the update to the other
-				// side until the latest monitor has been pulled from us and stored.
 				self.monitor_pending_commitment_signed = true;
-				self.send_commitment_no_status_check()?;
+				let (_, mut additional_update) = self.send_commitment_no_status_check().map_err(|e| (None, e))?;
+				// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
+				// strictly increasing by one, so decrement it here.
+				self.latest_monitor_update_id = monitor_update.update_id;
+				monitor_update.updates.append(&mut additional_update.updates);
 			}
 			// TODO: Call maybe_propose_first_closing_signed on restoration (or call it here and
 			// re-send the message on restoration)
-			return Err(ChannelError::Ignore("Previous monitor update failure prevented generation of RAA"));
+			return Err((Some(monitor_update), ChannelError::Ignore("Previous monitor update failure prevented generation of RAA")));
 		}
 
-		let (our_commitment_signed, monitor_update, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
+		let (our_commitment_signed, closing_signed) = if need_our_commitment && (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
 			// If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
 			// we'll send one right away when we get the revoke_and_ack when we
 			// free_holding_cell_htlcs().
-			let (msg, monitor) = self.send_commitment_no_status_check()?;
-			(Some(msg), monitor, None)
+			let (msg, mut additional_update) = self.send_commitment_no_status_check().map_err(|e| (None, e))?;
+			// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
+			// strictly increasing by one, so decrement it here.
+			self.latest_monitor_update_id = monitor_update.update_id;
+			monitor_update.updates.append(&mut additional_update.updates);
+			(Some(msg), None)
 		} else if !need_our_commitment {
-			(None, self.channel_monitor.clone(), self.maybe_propose_first_closing_signed(fee_estimator))
-		} else { (None, self.channel_monitor.clone(), None) };
+			(None, self.maybe_propose_first_closing_signed(fee_estimator))
+		} else { (None, None) };
 
 		Ok((msgs::RevokeAndACK {
 			channel_id: self.channel_id,
@@ -1896,11 +1955,16 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	/// Used to fulfill holding_cell_htlcs when we get a remote ack (or implicitly get it by them
 	/// fulfilling or failing the last pending HTLC)
-	fn free_holding_cell_htlcs(&mut self) -> Result<Option<(msgs::CommitmentUpdate, ChannelMonitor<ChanSigner>)>, ChannelError<ChanSigner>> {
+	fn free_holding_cell_htlcs(&mut self) -> Result<Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, ChannelError> {
 		assert_eq!(self.channel_state & ChannelState::MonitorUpdateFailed as u32, 0);
 		if self.holding_cell_htlc_updates.len() != 0 || self.holding_cell_update_fee.is_some() {
 			log_trace!(self, "Freeing holding cell with {} HTLC updates{}", self.holding_cell_htlc_updates.len(), if self.holding_cell_update_fee.is_some() { " and a fee update" } else { "" });
 
+			let mut monitor_update = ChannelMonitorUpdate {
+				update_id: self.latest_monitor_update_id + 1, // We don't increment this yet!
+				updates: Vec::new(),
+			};
+
 			let mut htlc_updates = Vec::new();
 			mem::swap(&mut htlc_updates, &mut self.holding_cell_htlc_updates);
 			let mut update_add_htlcs = Vec::with_capacity(htlc_updates.len());
@@ -1935,7 +1999,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						},
 						&HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
 							match self.get_update_fulfill_htlc(htlc_id, *payment_preimage) {
-								Ok(update_fulfill_msg_option) => update_fulfill_htlcs.push(update_fulfill_msg_option.0.unwrap()),
+								Ok((update_fulfill_msg_option, additional_monitor_update_opt)) => {
+									update_fulfill_htlcs.push(update_fulfill_msg_option.unwrap());
+									if let Some(mut additional_monitor_update) = additional_monitor_update_opt {
+										monitor_update.updates.append(&mut additional_monitor_update.updates);
+									}
+								},
 								Err(e) => {
 									if let ChannelError::Ignore(_) = e {}
 									else {
@@ -1985,7 +2054,13 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						} else {
 							None
 						};
-					let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
+
+					let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check()?;
+					// send_commitment_no_status_check and get_update_fulfill_htlc may bump latest_monitor_id
+					// but we want them to be strictly increasing by one, so reset it here.
+					self.latest_monitor_update_id = monitor_update.update_id;
+					monitor_update.updates.append(&mut additional_update.updates);
+
 					Ok(Some((msgs::CommitmentUpdate {
 						update_add_htlcs,
 						update_fulfill_htlcs,
@@ -2007,7 +2082,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// waiting on this revoke_and_ack. The generation of this new commitment_signed may also fail,
 	/// generating an appropriate error *after* the channel state has been updated based on the
 	/// revoke_and_ack message.
-	pub fn revoke_and_ack(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &FeeEstimator) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<msgs::ClosingSigned>, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	pub fn revoke_and_ack<F: Deref>(&mut self, msg: &msgs::RevokeAndACK, fee_estimator: &F) -> Result<(Option<msgs::CommitmentUpdate>, Vec<(PendingHTLCInfo, u64)>, Vec<(HTLCSource, PaymentHash, HTLCFailReason)>, Option<msgs::ClosingSigned>, ChannelMonitorUpdate), ChannelError>
+		where F::Target: FeeEstimator
+	{
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state"));
 		}
@@ -2023,10 +2100,6 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				return Err(ChannelError::Close("Got a revoke commitment secret which didn't correspond to their current pubkey"));
 			}
 		}
-		self.commitment_secrets.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret)
-			.map_err(|_| ChannelError::Close("Previous secrets did not match new one"))?;
-		self.channel_monitor.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret)
-			.unwrap();
 
 		if self.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
 			// Our counterparty seems to have burned their coins to us (by revoking a state when we
@@ -2039,6 +2112,18 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			return Err(ChannelError::Close("Received an unexpected revoke_and_ack"));
 		}
 
+		self.commitment_secrets.provide_secret(self.cur_remote_commitment_transaction_number + 1, msg.per_commitment_secret)
+			.map_err(|_| ChannelError::Close("Previous secrets did not match new one"))?;
+		self.latest_monitor_update_id += 1;
+		let mut monitor_update = ChannelMonitorUpdate {
+			update_id: self.latest_monitor_update_id,
+			updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
+				idx: self.cur_remote_commitment_transaction_number + 1,
+				secret: msg.per_commitment_secret,
+			}],
+		};
+		self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
+
 		// Update state now that we've passed all the can-fail calls...
 		// (note that we may still fail to generate the new commitment_signed message, but that's
 		// OK, we step the channel here and *then* if the new generation fails we can fail the
@@ -2164,28 +2249,44 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				// When the monitor updating is restored we'll call get_last_commitment_update(),
 				// which does not update state, but we're definitely now awaiting a remote revoke
 				// before we can step forward any more, so set it here.
-				self.send_commitment_no_status_check()?;
+				let (_, mut additional_update) = self.send_commitment_no_status_check()?;
+				// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
+				// strictly increasing by one, so decrement it here.
+				self.latest_monitor_update_id = monitor_update.update_id;
+				monitor_update.updates.append(&mut additional_update.updates);
 			}
 			self.monitor_pending_forwards.append(&mut to_forward_infos);
 			self.monitor_pending_failures.append(&mut revoked_htlcs);
-			return Ok((None, Vec::new(), Vec::new(), None, self.channel_monitor.clone()));
+			return Ok((None, Vec::new(), Vec::new(), None, monitor_update))
 		}
 
 		match self.free_holding_cell_htlcs()? {
-			Some(mut commitment_update) => {
-				commitment_update.0.update_fail_htlcs.reserve(update_fail_htlcs.len());
+			Some((mut commitment_update, mut additional_update)) => {
+				commitment_update.update_fail_htlcs.reserve(update_fail_htlcs.len());
 				for fail_msg in update_fail_htlcs.drain(..) {
-					commitment_update.0.update_fail_htlcs.push(fail_msg);
+					commitment_update.update_fail_htlcs.push(fail_msg);
 				}
-				commitment_update.0.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
+				commitment_update.update_fail_malformed_htlcs.reserve(update_fail_malformed_htlcs.len());
 				for fail_msg in update_fail_malformed_htlcs.drain(..) {
-					commitment_update.0.update_fail_malformed_htlcs.push(fail_msg);
+					commitment_update.update_fail_malformed_htlcs.push(fail_msg);
 				}
-				Ok((Some(commitment_update.0), to_forward_infos, revoked_htlcs, None, commitment_update.1))
+
+				// free_holding_cell_htlcs may bump latest_monitor_id multiple times but we want them to be
+				// strictly increasing by one, so decrement it here.
+				self.latest_monitor_update_id = monitor_update.update_id;
+				monitor_update.updates.append(&mut additional_update.updates);
+
+				Ok((Some(commitment_update), to_forward_infos, revoked_htlcs, None, monitor_update))
 			},
 			None => {
 				if require_commitment {
-					let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
+					let (commitment_signed, mut additional_update) = self.send_commitment_no_status_check()?;
+
+					// send_commitment_no_status_check may bump latest_monitor_id but we want them to be
+					// strictly increasing by one, so decrement it here.
+					self.latest_monitor_update_id = monitor_update.update_id;
+					monitor_update.updates.append(&mut additional_update.updates);
+
 					Ok((Some(msgs::CommitmentUpdate {
 						update_add_htlcs: Vec::new(),
 						update_fulfill_htlcs: Vec::new(),
@@ -2195,7 +2296,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						commitment_signed
 					}), to_forward_infos, revoked_htlcs, None, monitor_update))
 				} else {
-					Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), self.channel_monitor.clone()))
+					Ok((None, to_forward_infos, revoked_htlcs, self.maybe_propose_first_closing_signed(fee_estimator), monitor_update))
 				}
 			}
 		}
@@ -2230,7 +2331,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		})
 	}
 
-	pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitor<ChanSigner>)>, ChannelError<ChanSigner>> {
+	pub fn send_update_fee_and_commit(&mut self, feerate_per_kw: u64) -> Result<Option<(msgs::UpdateFee, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> {
 		match self.send_update_fee(feerate_per_kw) {
 			Some(update_fee) => {
 				let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
@@ -2381,7 +2482,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		(raa, commitment_update, order, forwards, failures, needs_broadcast_safe, funding_locked)
 	}
 
-	pub fn update_fee(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::UpdateFee) -> Result<(), ChannelError<ChanSigner>> {
+	pub fn update_fee<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
+		where F::Target: FeeEstimator
+	{
 		if self.channel_outbound {
 			return Err(ChannelError::Close("Non-funding remote tried to update channel fee"));
 		}
@@ -2390,7 +2493,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		}
 		Channel::<ChanSigner>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
 		self.pending_update_fee = Some(msg.feerate_per_kw as u64);
-		self.channel_update_count += 1;
+		self.update_time_counter += 1;
 		Ok(())
 	}
 
@@ -2463,7 +2566,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	/// May panic if some calls other than message-handling calls (which will all Err immediately)
 	/// have been called between remove_uncommitted_htlcs_and_mark_paused and this call.
-	pub fn channel_reestablish(&mut self, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitor<ChanSigner>>, RAACommitmentOrder, Option<msgs::Shutdown>), ChannelError<ChanSigner>> {
+	pub fn channel_reestablish(&mut self, msg: &msgs::ChannelReestablish) -> Result<(Option<msgs::FundingLocked>, Option<msgs::RevokeAndACK>, Option<msgs::CommitmentUpdate>, Option<ChannelMonitorUpdate>, RAACommitmentOrder, Option<msgs::Shutdown>), ChannelError> {
 		if self.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
 			// While BOLT 2 doesn't indicate explicitly we should error this channel here, it
 			// almost certainly indicates we are going to end up out-of-sync in some way, so we
@@ -2483,8 +2586,18 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided"));
 					}
 					if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.cur_local_commitment_transaction_number {
-						self.channel_monitor.provide_rescue_remote_commitment_tx_info(data_loss.my_current_per_commitment_point);
-						return Err(ChannelError::CloseDelayBroadcast { msg: "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting", update: Some(self.channel_monitor.clone())});
+						self.latest_monitor_update_id += 1;
+						let monitor_update = ChannelMonitorUpdate {
+							update_id: self.latest_monitor_update_id,
+							updates: vec![ChannelMonitorUpdateStep::RescueRemoteCommitmentTXInfo {
+								their_current_per_commitment_point: data_loss.my_current_per_commitment_point
+							}]
+						};
+						self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
+						return Err(ChannelError::CloseDelayBroadcast {
+							msg: "We have fallen behind - we have received proof that if we broadcast remote is going to claim our funds - we can't do any automated broadcasting",
+							update: monitor_update
+						});
 					}
 				},
 				OptionalField::Absent => {}
@@ -2568,7 +2681,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				match self.free_holding_cell_htlcs() {
 					Err(ChannelError::Close(msg)) => return Err(ChannelError::Close(msg)),
 					Err(ChannelError::Ignore(_)) | Err(ChannelError::CloseDelayBroadcast { .. }) => panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
-					Ok(Some((commitment_update, channel_monitor))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(channel_monitor), self.resend_order.clone(), shutdown_msg)),
+					Ok(Some((commitment_update, monitor_update))) => return Ok((resend_funding_locked, required_revoke, Some(commitment_update), Some(monitor_update), self.resend_order.clone(), shutdown_msg)),
 					Ok(None) => return Ok((resend_funding_locked, required_revoke, None, None, self.resend_order.clone(), shutdown_msg)),
 				}
 			} else {
@@ -2592,7 +2705,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		}
 	}
 
-	fn maybe_propose_first_closing_signed(&mut self, fee_estimator: &FeeEstimator) -> Option<msgs::ClosingSigned> {
+	fn maybe_propose_first_closing_signed<F: Deref>(&mut self, fee_estimator: &F) -> Option<msgs::ClosingSigned>
+		where F::Target: FeeEstimator
+	{
 		if !self.channel_outbound || !self.pending_inbound_htlcs.is_empty() || !self.pending_outbound_htlcs.is_empty() ||
 				self.channel_state & (BOTH_SIDES_SHUTDOWN_MASK | ChannelState::AwaitingRemoteRevoke as u32) != BOTH_SIDES_SHUTDOWN_MASK ||
 				self.last_sent_closing_fee.is_some() || self.pending_update_fee.is_some() {
@@ -2620,7 +2735,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		})
 	}
 
-	pub fn shutdown(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError<ChanSigner>> {
+	pub fn shutdown<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::Shutdown) -> Result<(Option<msgs::Shutdown>, Option<msgs::ClosingSigned>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
+		where F::Target: FeeEstimator
+	{
 		if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
 			return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish"));
 		}
@@ -2659,7 +2776,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		// From here on out, we may not fail!
 
 		self.channel_state |= ChannelState::RemoteShutdownSent as u32;
-		self.channel_update_count += 1;
+		self.update_time_counter += 1;
 
 		// We can't send our shutdown until we've committed all of our pending HTLCs, but the
 		// remote side is unlikely to accept any new HTLCs, so we go ahead and "free" any holding
@@ -2689,7 +2806,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		};
 
 		self.channel_state |= ChannelState::LocalShutdownSent as u32;
-		self.channel_update_count += 1;
+		self.update_time_counter += 1;
 
 		Ok((our_shutdown, self.maybe_propose_first_closing_signed(fee_estimator), dropped_outbound_htlcs))
 	}
@@ -2716,7 +2833,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		tx.input[0].witness.push(self.get_funding_redeemscript().into_bytes());
 	}
 
-	pub fn closing_signed(&mut self, fee_estimator: &FeeEstimator, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError<ChanSigner>> {
+	pub fn closing_signed<F: Deref>(&mut self, fee_estimator: &F, msg: &msgs::ClosingSigned) -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
+		where F::Target: FeeEstimator
+	{
 		if self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
 			return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown"));
 		}
@@ -2754,7 +2873,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			if last_fee == msg.fee_satoshis {
 				self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &our_sig);
 				self.channel_state = ChannelState::ShutdownComplete as u32;
-				self.channel_update_count += 1;
+				self.update_time_counter += 1;
 				return Ok((None, Some(closing_tx)));
 			}
 		}
@@ -2804,7 +2923,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &our_sig);
 
 		self.channel_state = ChannelState::ShutdownComplete as u32;
-		self.channel_update_count += 1;
+		self.update_time_counter += 1;
 
 		Ok((Some(msgs::ClosingSigned {
 			channel_id: self.channel_id,
@@ -2830,7 +2949,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		if self.channel_state < ChannelState::FundingCreated as u32 {
 			panic!("Can't get a channel monitor until funding has been created");
 		}
-		&mut self.channel_monitor
+		self.channel_monitor.as_mut().unwrap()
 	}
 
 	/// Guaranteed to be Some after both FundingLocked messages have been exchanged (and, thus,
@@ -2916,8 +3035,8 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	}
 
 	/// Allowed in any state (including after shutdown)
-	pub fn get_channel_update_count(&self) -> u32 {
-		self.channel_update_count
+	pub fn get_update_time_counter(&self) -> u32 {
+		self.update_time_counter
 	}
 
 	pub fn get_latest_monitor_update_id(&self) -> u64 {
@@ -2934,7 +3053,9 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 
 	/// Gets the fee we'd want to charge for adding an HTLC output to this Channel
 	/// Allowed in any state (including after shutdown)
-	pub fn get_our_fee_base_msat(&self, fee_estimator: &FeeEstimator) -> u32 {
+	pub fn get_our_fee_base_msat<F: Deref>(&self, fee_estimator: &F) -> u32
+		where F::Target: FeeEstimator
+	{
 		// For lack of a better metric, we calculate what it would cost to consolidate the new HTLC
 		// output value back into a transaction with the regular channel output:
 
@@ -3041,7 +3162,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 							panic!("Client called ChannelManager::funding_transaction_generated with bogus transaction!");
 						}
 						self.channel_state = ChannelState::ShutdownComplete as u32;
-						self.channel_update_count += 1;
+						self.update_time_counter += 1;
 						return Err(msgs::ErrorMessage {
 							channel_id: self.channel_id(),
 							data: "funding tx had wrong script/value".to_owned()
@@ -3067,7 +3188,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		}
 		if header.bitcoin_hash() != self.last_block_connected {
 			self.last_block_connected = header.bitcoin_hash();
-			self.channel_monitor.last_block_hash = self.last_block_connected;
+			self.update_time_counter = cmp::max(self.update_time_counter, header.time);
+			if let Some(channel_monitor) = self.channel_monitor.as_mut() {
+				channel_monitor.last_block_hash = self.last_block_connected;
+			}
 			if self.funding_tx_confirmations > 0 {
 				if self.funding_tx_confirmations == self.minimum_depth as u64 {
 					let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
@@ -3075,7 +3199,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 						true
 					} else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirFundingLocked as u32) {
 						self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
-						self.channel_update_count += 1;
+						self.update_time_counter += 1;
 						true
 					} else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurFundingLocked as u32) {
 						// We got a reorg but not enough to trigger a force close, just update
@@ -3127,14 +3251,18 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			self.funding_tx_confirmations = self.minimum_depth as u64 - 1;
 		}
 		self.last_block_connected = header.bitcoin_hash();
-		self.channel_monitor.last_block_hash = self.last_block_connected;
+		if let Some(channel_monitor) = self.channel_monitor.as_mut() {
+			channel_monitor.last_block_hash = self.last_block_connected;
+		}
 		false
 	}
 
 	// Methods to get unprompted messages to send to the remote end (or where we already returned
 	// something in the handler for the message that prompted this message):
 
-	pub fn get_open_channel(&self, chain_hash: Sha256dHash, fee_estimator: &FeeEstimator) -> msgs::OpenChannel {
+	pub fn get_open_channel<F: Deref>(&self, chain_hash: Sha256dHash, fee_estimator: &F) -> msgs::OpenChannel
+		where F::Target: FeeEstimator
+	{
 		if !self.channel_outbound {
 			panic!("Tried to open a channel for an inbound channel?");
 		}
@@ -3204,7 +3332,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	}
 
 	/// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
-	fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), ChannelError<ChanSigner>> {
+	fn get_outbound_funding_created_signature(&mut self) -> Result<(Signature, Transaction), ChannelError> {
 		let remote_keys = self.build_remote_transaction_keys()?;
 		let remote_initial_commitment_tx = self.build_commitment_transaction(self.cur_remote_commitment_transaction_number, &remote_keys, false, false, self.feerate_per_kw).0;
 		Ok((self.local_keys.sign_remote_commitment(self.feerate_per_kw, &remote_initial_commitment_tx, &remote_keys, &Vec::new(), self.our_to_self_delay, &self.secp_ctx)
@@ -3218,7 +3346,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// Note that channel_id changes during this call!
 	/// Do NOT broadcast the funding transaction until after a successful funding_signed call!
 	/// If an Err is returned, it is a ChannelError::Close.
-	pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	pub fn get_outbound_funding_created(&mut self, funding_txo: OutPoint) -> Result<(msgs::FundingCreated, ChannelMonitor<ChanSigner>), ChannelError> {
 		if !self.channel_outbound {
 			panic!("Tried to create outbound funding_created message on an inbound channel!");
 		}
@@ -3241,12 +3369,31 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			}
 		};
 
-		let funding_txo_script = self.get_funding_redeemscript().to_v0_p2wsh();
-		self.channel_monitor.set_funding_info((funding_txo, funding_txo_script));
 		let temporary_channel_id = self.channel_id;
 
 		// Now that we're past error-generating stuff, update our local state:
-		self.channel_monitor.provide_latest_remote_commitment_tx_info(&commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
+
+		let their_pubkeys = self.their_pubkeys.as_ref().unwrap();
+		let funding_redeemscript = self.get_funding_redeemscript();
+		let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+		macro_rules! create_monitor {
+			() => { {
+				let mut channel_monitor = ChannelMonitor::new(self.local_keys.clone(),
+				                                              &self.shutdown_pubkey, self.our_to_self_delay,
+				                                              &self.destination_script, (funding_txo, funding_txo_script.clone()),
+				                                              &their_pubkeys.htlc_basepoint, &their_pubkeys.delayed_payment_basepoint,
+				                                              self.their_to_self_delay, funding_redeemscript.clone(), self.channel_value_satoshis,
+				                                              self.get_commitment_transaction_number_obscure_factor(),
+				                                              self.logger.clone());
+
+				channel_monitor.provide_latest_remote_commitment_tx_info(&commitment_tx, Vec::new(), self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
+				channel_monitor
+			} }
+		}
+
+		self.channel_monitor = Some(create_monitor!());
+		let channel_monitor = create_monitor!();
+
 		self.channel_state = ChannelState::FundingCreated as u32;
 		self.channel_id = funding_txo.to_channel_id();
 		self.cur_remote_commitment_transaction_number -= 1;
@@ -3256,7 +3403,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 			funding_txid: funding_txo.txid,
 			funding_output_index: funding_txo.index,
 			signature: our_signature
-		}, self.channel_monitor.clone()))
+		}, channel_monitor))
 	}
 
 	/// Gets an UnsignedChannelAnnouncement, as well as a signature covering it using our
@@ -3267,7 +3414,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// closing).
 	/// Note that the "channel must be funded" requirement is stricter than BOLT 7 requires - see
 	/// https://github.com/lightningnetwork/lightning-rfc/issues/468
-	pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: Sha256dHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError<ChanSigner>> {
+	pub fn get_channel_announcement(&self, our_node_id: PublicKey, chain_hash: Sha256dHash) -> Result<(msgs::UnsignedChannelAnnouncement, Signature), ChannelError> {
 		if !self.config.announced_channel {
 			return Err(ChannelError::Ignore("Channel is not available for public announcements"));
 		}
@@ -3311,10 +3458,10 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 				my_current_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number + 1))
 			})
 		} else {
-			log_debug!(self, "We don't seen yet any revoked secret, if this channnel has already been updated it means we are fallen-behind, you should wait for other peer closing");
+			log_info!(self, "Sending a data_loss_protect with no previous remote per_commitment_secret");
 			OptionalField::Present(DataLossProtect {
 				your_last_per_commitment_secret: [0;32],
-				my_current_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number))
+				my_current_per_commitment_point: PublicKey::from_secret_key(&self.secp_ctx, &self.build_local_commitment_secret(self.cur_local_commitment_transaction_number + 1))
 			})
 		};
 		msgs::ChannelReestablish {
@@ -3351,7 +3498,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// HTLCs on the wire or we wouldn't be able to determine what they actually ACK'ed.
 	/// You MUST call send_commitment prior to any other calls on this Channel
 	/// If an Err is returned, it's a ChannelError::Ignore!
-	pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError<ChanSigner>> {
+	pub fn send_htlc(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
 			return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down"));
 		}
@@ -3359,6 +3506,11 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		if amount_msat > self.channel_value_satoshis * 1000 {
 			return Err(ChannelError::Ignore("Cannot send more than the total value of the channel"));
 		}
+
+		if amount_msat == 0 {
+			return Err(ChannelError::Ignore("Cannot send 0-msat HTLC"));
+		}
+
 		if amount_msat < self.their_htlc_minimum_msat {
 			return Err(ChannelError::Ignore("Cannot send less than their minimum HTLC value"));
 		}
@@ -3428,7 +3580,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// Always returns a ChannelError::Close if an immediately-preceding (read: the
 	/// last call to this Channel) send_htlc returned Ok(Some(_)) and there is an Err.
 	/// May panic if called except immediately after a successful, Ok(Some(_))-returning send_htlc.
-	pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	pub fn send_commitment(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> {
 		if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
 			panic!("Cannot create commitment tx until channel is fully established");
 		}
@@ -3460,7 +3612,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		self.send_commitment_no_status_check()
 	}
 	/// Only fails in case of bad keys
-	fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitor<ChanSigner>), ChannelError<ChanSigner>> {
+	fn send_commitment_no_status_check(&mut self) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> {
 		// We can upgrade the status of some HTLCs that are waiting on a commitment, even if we
 		// fail to generate this, we still are at least at a position where upgrading their status
 		// is acceptable.
@@ -3484,20 +3636,31 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		let (res, remote_commitment_tx, htlcs) = match self.send_commitment_no_state_update() {
 			Ok((res, (remote_commitment_tx, mut htlcs))) => {
 				// Update state now that we've passed all the can-fail calls...
-				let htlcs_no_ref = htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
+				let htlcs_no_ref: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)> =
+					htlcs.drain(..).map(|(htlc, htlc_source)| (htlc, htlc_source.map(|source_ref| Box::new(source_ref.clone())))).collect();
 				(res, remote_commitment_tx, htlcs_no_ref)
 			},
 			Err(e) => return Err(e),
 		};
 
-		self.channel_monitor.provide_latest_remote_commitment_tx_info(&remote_commitment_tx, htlcs, self.cur_remote_commitment_transaction_number, self.their_cur_commitment_point.unwrap());
+		self.latest_monitor_update_id += 1;
+		let monitor_update = ChannelMonitorUpdate {
+			update_id: self.latest_monitor_update_id,
+			updates: vec![ChannelMonitorUpdateStep::LatestRemoteCommitmentTXInfo {
+				unsigned_commitment_tx: remote_commitment_tx.clone(),
+				htlc_outputs: htlcs.clone(),
+				commitment_number: self.cur_remote_commitment_transaction_number,
+				their_revocation_point: self.their_cur_commitment_point.unwrap()
+			}]
+		};
+		self.channel_monitor.as_mut().unwrap().update_monitor_ooo(monitor_update.clone()).unwrap();
 		self.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
-		Ok((res, self.channel_monitor.clone()))
+		Ok((res, monitor_update))
 	}
 
 	/// Only fails in case of bad keys. Used for channel_reestablish commitment_signed generation
 	/// when we shouldn't change HTLC/channel state.
-	fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError<ChanSigner>> {
+	fn send_commitment_no_state_update(&self) -> Result<(msgs::CommitmentSigned, (Transaction, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> {
 		let mut feerate_per_kw = self.feerate_per_kw;
 		if let Some(feerate) = self.pending_update_fee {
 			if self.channel_outbound {
@@ -3545,7 +3708,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// to send to the remote peer in one go.
 	/// Shorthand for calling send_htlc() followed by send_commitment(), see docs on those for
 	/// more info.
-	pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitor<ChanSigner>)>, ChannelError<ChanSigner>> {
+	pub fn send_htlc_and_commit(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket) -> Result<Option<(msgs::UpdateAddHTLC, msgs::CommitmentSigned, ChannelMonitorUpdate)>, ChannelError> {
 		match self.send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet)? {
 			Some(update_add_htlc) => {
 				let (commitment_signed, monitor_update) = self.send_commitment_no_status_check()?;
@@ -3584,7 +3747,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		} else {
 			self.channel_state |= ChannelState::LocalShutdownSent as u32;
 		}
-		self.channel_update_count += 1;
+		self.update_time_counter += 1;
 
 		// Go ahead and drop holding cell updates as we'd rather fail payments than wait to send
 		// our shutdown until we've committed all of the pending changes.
@@ -3611,7 +3774,7 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 	/// those explicitly stated to be allowed after shutdown completes, eg some simple getters).
 	/// Also returns the list of payment_hashes for channels which we can safely fail backwards
 	/// immediately (others we will have to allow to time out).
-	pub fn force_shutdown(&mut self) -> (Vec<Transaction>, Vec<(HTLCSource, PaymentHash)>) {
+	pub fn force_shutdown(&mut self, should_broadcast: bool) -> (Option<OutPoint>, ChannelMonitorUpdate, Vec<(HTLCSource, PaymentHash)>) {
 		assert!(self.channel_state != ChannelState::ShutdownComplete as u32);
 
 		// We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
@@ -3633,8 +3796,12 @@ impl<ChanSigner: ChannelKeys> Channel<ChanSigner> {
 		}
 
 		self.channel_state = ChannelState::ShutdownComplete as u32;
-		self.channel_update_count += 1;
-		(self.channel_monitor.get_latest_local_commitment_txn(), dropped_outbound_htlcs)
+		self.update_time_counter += 1;
+		self.latest_monitor_update_id += 1;
+		(self.funding_txo.clone(), ChannelMonitorUpdate {
+			update_id: self.latest_monitor_update_id,
+			updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
+		}, dropped_outbound_htlcs)
 	}
 }
 
@@ -3662,9 +3829,9 @@ impl Writeable for InboundHTLCRemovalReason {
 	}
 }
 
-impl<R: ::std::io::Read> Readable<R> for InboundHTLCRemovalReason {
-	fn read(reader: &mut R) -> Result<Self, DecodeError> {
-		Ok(match <u8 as Readable<R>>::read(reader)? {
+impl Readable for InboundHTLCRemovalReason {
+	fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+		Ok(match <u8 as Readable>::read(reader)? {
 			0 => InboundHTLCRemovalReason::FailRelay(Readable::read(reader)?),
 			1 => InboundHTLCRemovalReason::FailMalformed((Readable::read(reader)?, Readable::read(reader)?)),
 			2 => InboundHTLCRemovalReason::Fulfill(Readable::read(reader)?),
@@ -3693,6 +3860,7 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 
 		self.local_keys.write(writer)?;
 		self.shutdown_pubkey.write(writer)?;
+		self.destination_script.write(writer)?;
 
 		self.cur_local_commitment_transaction_number.write(writer)?;
 		self.cur_remote_commitment_transaction_number.write(writer)?;
@@ -3733,18 +3901,6 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 			}
 		}
 
-		macro_rules! write_option {
-			($thing: expr) => {
-				match &$thing {
-					&None => 0u8.write(writer)?,
-					&Some(ref v) => {
-						1u8.write(writer)?;
-						v.write(writer)?;
-					},
-				}
-			}
-		}
-
 		(self.pending_outbound_htlcs.len() as u64).write(writer)?;
 		for htlc in self.pending_outbound_htlcs.iter() {
 			htlc.htlc_id.write(writer)?;
@@ -3762,15 +3918,15 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 				},
 				&OutboundHTLCState::RemoteRemoved(ref fail_reason) => {
 					2u8.write(writer)?;
-					write_option!(*fail_reason);
+					fail_reason.write(writer)?;
 				},
 				&OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref fail_reason) => {
 					3u8.write(writer)?;
-					write_option!(*fail_reason);
+					fail_reason.write(writer)?;
 				},
 				&OutboundHTLCState::AwaitingRemovedRemoteRevoke(ref fail_reason) => {
 					4u8.write(writer)?;
-					write_option!(*fail_reason);
+					fail_reason.write(writer)?;
 				},
 			}
 		}
@@ -3821,12 +3977,12 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 			fail_reason.write(writer)?;
 		}
 
-		write_option!(self.pending_update_fee);
-		write_option!(self.holding_cell_update_fee);
+		self.pending_update_fee.write(writer)?;
+		self.holding_cell_update_fee.write(writer)?;
 
 		self.next_local_htlc_id.write(writer)?;
 		(self.next_remote_htlc_id - dropped_inbound_htlcs).write(writer)?;
-		self.channel_update_count.write(writer)?;
+		self.update_time_counter.write(writer)?;
 		self.feerate_per_kw.write(writer)?;
 
 		match self.last_sent_closing_fee {
@@ -3839,9 +3995,9 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 			None => 0u8.write(writer)?,
 		}
 
-		write_option!(self.funding_txo);
-		write_option!(self.funding_tx_confirmed_in);
-		write_option!(self.short_channel_id);
+		self.funding_txo.write(writer)?;
+		self.funding_tx_confirmed_in.write(writer)?;
+		self.short_channel_id.write(writer)?;
 
 		self.last_block_connected.write(writer)?;
 		self.funding_tx_confirmations.write(writer)?;
@@ -3857,23 +4013,23 @@ impl<ChanSigner: ChannelKeys + Writeable> Writeable for Channel<ChanSigner> {
 		self.their_max_accepted_htlcs.write(writer)?;
 		self.minimum_depth.write(writer)?;
 
-		write_option!(self.their_pubkeys);
-		write_option!(self.their_cur_commitment_point);
+		self.their_pubkeys.write(writer)?;
+		self.their_cur_commitment_point.write(writer)?;
 
-		write_option!(self.their_prev_commitment_point);
+		self.their_prev_commitment_point.write(writer)?;
 		self.their_node_id.write(writer)?;
 
-		write_option!(self.their_shutdown_scriptpubkey);
+		self.their_shutdown_scriptpubkey.write(writer)?;
 
 		self.commitment_secrets.write(writer)?;
 
-		self.channel_monitor.write_for_disk(writer)?;
+		self.channel_monitor.as_ref().unwrap().write_for_disk(writer)?;
 		Ok(())
 	}
 }
 
-impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R, Arc<Logger>> for Channel<ChanSigner> {
-	fn read(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
+impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for Channel<ChanSigner> {
+	fn read<R : ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
 		let _ver: u8 = Readable::read(reader)?;
 		let min_ver: u8 = Readable::read(reader)?;
 		if min_ver > SERIALIZATION_VERSION {
@@ -3892,6 +4048,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 
 		let local_keys = Readable::read(reader)?;
 		let shutdown_pubkey = Readable::read(reader)?;
+		let destination_script = Readable::read(reader)?;
 
 		let cur_local_commitment_transaction_number = Readable::read(reader)?;
 		let cur_remote_commitment_transaction_number = Readable::read(reader)?;
@@ -3905,7 +4062,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 				amount_msat: Readable::read(reader)?,
 				cltv_expiry: Readable::read(reader)?,
 				payment_hash: Readable::read(reader)?,
-				state: match <u8 as Readable<R>>::read(reader)? {
+				state: match <u8 as Readable>::read(reader)? {
 					1 => InboundHTLCState::AwaitingRemoteRevokeToAnnounce(Readable::read(reader)?),
 					2 => InboundHTLCState::AwaitingAnnouncedRemoteRevoke(Readable::read(reader)?),
 					3 => InboundHTLCState::Committed,
@@ -3924,7 +4081,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 				cltv_expiry: Readable::read(reader)?,
 				payment_hash: Readable::read(reader)?,
 				source: Readable::read(reader)?,
-				state: match <u8 as Readable<R>>::read(reader)? {
+				state: match <u8 as Readable>::read(reader)? {
 					0 => OutboundHTLCState::LocalAnnounced(Box::new(Readable::read(reader)?)),
 					1 => OutboundHTLCState::Committed,
 					2 => OutboundHTLCState::RemoteRemoved(Readable::read(reader)?),
@@ -3938,7 +4095,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 		let holding_cell_htlc_update_count: u64 = Readable::read(reader)?;
 		let mut holding_cell_htlc_updates = Vec::with_capacity(cmp::min(holding_cell_htlc_update_count as usize, OUR_MAX_HTLCS as usize*2));
 		for _ in 0..holding_cell_htlc_update_count {
-			holding_cell_htlc_updates.push(match <u8 as Readable<R>>::read(reader)? {
+			holding_cell_htlc_updates.push(match <u8 as Readable>::read(reader)? {
 				0 => HTLCUpdateAwaitingACK::AddHTLC {
 					amount_msat: Readable::read(reader)?,
 					cltv_expiry: Readable::read(reader)?,
@@ -3958,7 +4115,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 			});
 		}
 
-		let resend_order = match <u8 as Readable<R>>::read(reader)? {
+		let resend_order = match <u8 as Readable>::read(reader)? {
 			0 => RAACommitmentOrder::CommitmentFirst,
 			1 => RAACommitmentOrder::RevokeAndACKFirst,
 			_ => return Err(DecodeError::InvalidValue),
@@ -3985,10 +4142,10 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 
 		let next_local_htlc_id = Readable::read(reader)?;
 		let next_remote_htlc_id = Readable::read(reader)?;
-		let channel_update_count = Readable::read(reader)?;
+		let update_time_counter = Readable::read(reader)?;
 		let feerate_per_kw = Readable::read(reader)?;
 
-		let last_sent_closing_fee = match <u8 as Readable<R>>::read(reader)? {
+		let last_sent_closing_fee = match <u8 as Readable>::read(reader)? {
 			0 => None,
 			1 => Some((Readable::read(reader)?, Readable::read(reader)?, Readable::read(reader)?)),
 			_ => return Err(DecodeError::InvalidValue),
@@ -4042,6 +4199,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 
 			local_keys,
 			shutdown_pubkey,
+			destination_script,
 
 			cur_local_commitment_transaction_number,
 			cur_remote_commitment_transaction_number,
@@ -4063,7 +4221,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 			holding_cell_update_fee,
 			next_local_htlc_id,
 			next_remote_htlc_id,
-			channel_update_count,
+			update_time_counter,
 			feerate_per_kw,
 
 			#[cfg(debug_assertions)]
@@ -4098,7 +4256,7 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 
 			their_shutdown_scriptpubkey,
 
-			channel_monitor,
+			channel_monitor: Some(channel_monitor),
 			commitment_secrets,
 
 			network_sync: UpdateStatus::Fresh,
@@ -4110,22 +4268,28 @@ impl<R : ::std::io::Read, ChanSigner: ChannelKeys + Readable<R>> ReadableArgs<R,
 
 #[cfg(test)]
 mod tests {
+	use bitcoin::BitcoinHash;
 	use bitcoin::util::bip143;
 	use bitcoin::consensus::encode::serialize;
 	use bitcoin::blockdata::script::{Script, Builder};
-	use bitcoin::blockdata::transaction::Transaction;
+	use bitcoin::blockdata::transaction::{Transaction, TxOut};
+	use bitcoin::blockdata::constants::genesis_block;
 	use bitcoin::blockdata::opcodes;
+	use bitcoin::network::constants::Network;
 	use bitcoin_hashes::hex::FromHex;
 	use hex;
 	use ln::channelmanager::{HTLCSource, PaymentPreimage, PaymentHash};
 	use ln::channel::{Channel,ChannelKeys,InboundHTLCOutput,OutboundHTLCOutput,InboundHTLCState,OutboundHTLCState,HTLCOutputInCommitment,TxCreationKeys};
 	use ln::channel::MAX_FUNDING_SATOSHIS;
+	use ln::features::InitFeatures;
+	use ln::msgs::{OptionalField, DataLossProtect};
 	use ln::chan_utils;
 	use ln::chan_utils::{LocalCommitmentTransaction, ChannelPublicKeys};
 	use chain::chaininterface::{FeeEstimator,ConfirmationTarget};
 	use chain::keysinterface::{InMemoryChannelKeys, KeysInterface};
 	use chain::transaction::OutPoint;
 	use util::config::UserConfig;
+	use util::enforcing_trait_impls::EnforcingChannelKeys;
 	use util::test_utils;
 	use util::logger::Logger;
 	use secp256k1::{Secp256k1, Message, Signature, All};
@@ -4135,6 +4299,7 @@ mod tests {
 	use bitcoin_hashes::hash160::Hash as Hash160;
 	use bitcoin_hashes::Hash;
 	use std::sync::Arc;
+	use rand::{thread_rng,Rng};
 
 	struct TestFeeEstimator {
 		fee_est: u64
@@ -4182,6 +4347,70 @@ mod tests {
 		PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
 	}
 
+	#[test]
+	fn channel_reestablish_no_updates() {
+		let feeest = TestFeeEstimator{fee_est: 15000};
+		let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
+		let secp_ctx = Secp256k1::new();
+		let mut seed = [0; 32];
+		let mut rng = thread_rng();
+		rng.fill_bytes(&mut seed);
+		let network = Network::Testnet;
+		let keys_provider = test_utils::TestKeysInterface::new(&seed, network, logger.clone() as Arc<Logger>);
+
+		// Go through the flow of opening a channel between two nodes.
+
+		// Create Node A's channel
+		let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
+		let config = UserConfig::default();
+		let mut node_a_chan = Channel::<EnforcingChannelKeys>::new_outbound(&&feeest, &&keys_provider, node_a_node_id, 10000000, 100000, 42, Arc::clone(&logger), &config).unwrap();
+
+		// Create Node B's channel by receiving Node A's open_channel message
+		let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.bitcoin_hash(), &&feeest);
+		let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
+		let mut node_b_chan = Channel::<EnforcingChannelKeys>::new_from_req(&&feeest, &&keys_provider, node_b_node_id, InitFeatures::supported(), &open_channel_msg, 7, logger, &config).unwrap();
+
+		// Node B --> Node A: accept channel
+		let accept_channel_msg = node_b_chan.get_accept_channel();
+		node_a_chan.accept_channel(&accept_channel_msg, &config, InitFeatures::supported()).unwrap();
+
+		// Node A --> Node B: funding created
+		let output_script = node_a_chan.get_funding_redeemscript();
+		let tx = Transaction { version: 1, lock_time: 0, input: Vec::new(), output: vec![TxOut {
+			value: 10000000, script_pubkey: output_script.clone(),
+		}]};
+		let funding_outpoint = OutPoint::new(tx.txid(), 0);
+		let (funding_created_msg, _) = node_a_chan.get_outbound_funding_created(funding_outpoint).unwrap();
+		let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg).unwrap();
+
+		// Node B --> Node A: funding signed
+		let _ = node_a_chan.funding_signed(&funding_signed_msg);
+
+		// Now disconnect the two nodes and check that the commitment point in
+		// Node B's channel_reestablish message is sane.
+		node_b_chan.remove_uncommitted_htlcs_and_mark_paused();
+		let expected_commitment_point = PublicKey::from_secret_key(&secp_ctx, &node_b_chan.build_local_commitment_secret(node_b_chan.cur_local_commitment_transaction_number + 1));
+		let msg = node_b_chan.get_channel_reestablish();
+		match msg.data_loss_protect {
+			OptionalField::Present(DataLossProtect { my_current_per_commitment_point, .. }) => {
+				assert_eq!(expected_commitment_point, my_current_per_commitment_point);
+			},
+			_ => panic!()
+		}
+
+		// Check that the commitment point in Node A's channel_reestablish message
+		// is sane.
+		node_a_chan.remove_uncommitted_htlcs_and_mark_paused();
+		let expected_commitment_point = PublicKey::from_secret_key(&secp_ctx, &node_a_chan.build_local_commitment_secret(node_a_chan.cur_local_commitment_transaction_number + 1));
+		let msg = node_a_chan.get_channel_reestablish();
+		match msg.data_loss_protect {
+			OptionalField::Present(DataLossProtect { my_current_per_commitment_point, .. }) => {
+				assert_eq!(expected_commitment_point, my_current_per_commitment_point);
+			},
+			_ => panic!()
+		}
+	}
+
 	#[test]
 	fn outbound_commitment_test() {
 		// Test vectors from BOLT 3 Appendix C:
@@ -4204,12 +4433,12 @@ mod tests {
 
 		assert_eq!(PublicKey::from_secret_key(&secp_ctx, chan_keys.funding_key()).serialize()[..],
 				hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
-		let keys_provider: Arc<KeysInterface<ChanKeySigner = InMemoryChannelKeys>> = Arc::new(Keys { chan_keys });
+		let keys_provider = Keys { chan_keys: chan_keys.clone() };
 
 		let their_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
 		let mut config = UserConfig::default();
 		config.channel_options.announced_channel = false;
-		let mut chan = Channel::<InMemoryChannelKeys>::new_outbound(&feeest, &keys_provider, their_node_id, 10000000, 100000, 42, Arc::clone(&logger), &config).unwrap(); // Nothing uses their network key in this test
+		let mut chan = Channel::<InMemoryChannelKeys>::new_outbound(&&feeest, &&keys_provider, their_node_id, 10000000, 100000, 42, Arc::clone(&logger), &config).unwrap(); // Nothing uses their network key in this test
 		chan.their_to_self_delay = 144;
 		chan.our_dust_limit_satoshis = 546;
 
@@ -4246,6 +4475,7 @@ mod tests {
 
 		let mut unsigned_tx: (Transaction, Vec<HTLCOutputInCommitment>);
 
+		let mut localtx;
 		macro_rules! test_commitment {
 			( $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
 				unsigned_tx = {
@@ -4260,8 +4490,8 @@ mod tests {
 				let sighash = Message::from_slice(&bip143::SighashComponents::new(&unsigned_tx.0).sighash_all(&unsigned_tx.0.input[0], &redeemscript, chan.channel_value_satoshis)[..]).unwrap();
 				secp_ctx.verify(&sighash, &their_signature, chan.their_funding_pubkey()).unwrap();
 
-				let mut localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey());
-				localtx.add_local_sig(chan.local_keys.funding_key(), &redeemscript, chan.channel_value_satoshis, &chan.secp_ctx);
+				localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey());
+				chan_keys.sign_local_commitment(&mut localtx, &redeemscript, chan.channel_value_satoshis, &chan.secp_ctx);
 
 				assert_eq!(serialize(localtx.with_valid_witness())[..],
 						hex::decode($tx_hex).unwrap()[..]);
@@ -4269,11 +4499,11 @@ mod tests {
 		}
 
 		macro_rules! test_htlc_output {
-			( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr ) => {
+			( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
 				let remote_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
 
 				let ref htlc = unsigned_tx.1[$htlc_idx];
-				let mut htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
+				let htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
 				let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
 				let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap();
 				secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.b_htlc_key).unwrap();
@@ -4290,8 +4520,12 @@ mod tests {
 					assert!(preimage.is_some());
 				}
 
-				chan_utils::sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys.a_htlc_key, &keys.b_htlc_key, &keys.revocation_key, &keys.per_commitment_point, chan.local_keys.htlc_base_key(), &chan.secp_ctx).unwrap();
-				assert_eq!(serialize(&htlc_tx)[..],
+				let mut per_htlc = Vec::new();
+				per_htlc.push((htlc.clone(), Some(remote_signature), None));
+				localtx.set_htlc_cache(keys.clone(), chan.feerate_per_kw, per_htlc);
+				chan_keys.sign_htlc_transaction(&mut localtx, $htlc_idx, preimage, chan.their_to_self_delay, &chan.secp_ctx);
+
+				assert_eq!(serialize(localtx.htlc_with_valid_witness($htlc_idx).as_ref().unwrap())[..],
 						hex::decode($tx_hex).unwrap()[..]);
 			};
 		}