Remove unreachable `Err` cases when constructing `TxCreationKeys`
[rust-lightning] / lightning / src / ln / channel.rs
index 7af90c4f843e00ee1bf4aa30aa0eb0796ebbf15b..dcbaa771f93e1f1798dccb0d7c8eea47a0d80498 100644 (file)
@@ -244,9 +244,9 @@ enum HTLCUpdateAwaitingACK {
 /// There are a few "states" and then a number of flags which can be applied:
 /// We first move through init with OurInitSent -> TheirInitSent -> FundingCreated -> FundingSent.
 /// TheirChannelReady and OurChannelReady then get set on FundingSent, and when both are set we
-/// move on to ChannelFunded.
-/// Note that PeerDisconnected can be set on both ChannelFunded and FundingSent.
-/// ChannelFunded can then get all remaining flags set on it, until we finish shutdown, then we
+/// move on to ChannelReady.
+/// Note that PeerDisconnected can be set on both ChannelReady and FundingSent.
+/// ChannelReady can then get all remaining flags set on it, until we finish shutdown, then we
 /// move on to ShutdownComplete, at which point most calls into this channel are disallowed.
 enum ChannelState {
        /// Implies we have (or are prepared to) send our open_channel/accept_channel message
@@ -262,17 +262,17 @@ enum ChannelState {
        /// and our counterparty consider the funding transaction confirmed.
        FundingSent = 8,
        /// Flag which can be set on FundingSent to indicate they sent us a channel_ready message.
-       /// Once both TheirChannelReady and OurChannelReady are set, state moves on to ChannelFunded.
+       /// Once both TheirChannelReady and OurChannelReady are set, state moves on to ChannelReady.
        TheirChannelReady = 1 << 4,
        /// Flag which can be set on FundingSent to indicate we sent them a channel_ready message.
-       /// Once both TheirChannelReady and OurChannelReady are set, state moves on to ChannelFunded.
+       /// Once both TheirChannelReady and OurChannelReady are set, state moves on to ChannelReady.
        OurChannelReady = 1 << 5,
-       ChannelFunded = 64,
-       /// Flag which is set on ChannelFunded and FundingSent indicating remote side is considered
+       ChannelReady = 64,
+       /// Flag which is set on ChannelReady and FundingSent indicating remote side is considered
        /// "disconnected" and no updates are allowed until after we've done a channel_reestablish
        /// dance.
        PeerDisconnected = 1 << 7,
-       /// Flag which is set on ChannelFunded, FundingCreated, and FundingSent indicating the user has
+       /// Flag which is set on ChannelReady, FundingCreated, and FundingSent indicating the user has
        /// told us a ChannelMonitor update is pending async persistence somewhere and we should pause
        /// sending any outbound messages until they've managed to finish.
        MonitorUpdateInProgress = 1 << 8,
@@ -281,13 +281,13 @@ enum ChannelState {
        /// messages as then we will be unable to determine which HTLCs they included in their
        /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
        /// later.
-       /// Flag is set on ChannelFunded.
+       /// Flag is set on ChannelReady.
        AwaitingRemoteRevoke = 1 << 9,
-       /// Flag which is set on ChannelFunded or FundingSent after receiving a shutdown message from
+       /// Flag which is set on ChannelReady or FundingSent after receiving a shutdown message from
        /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
        /// to respond with our own shutdown message when possible.
        RemoteShutdownSent = 1 << 10,
-       /// Flag which is set on ChannelFunded or FundingSent after sending a shutdown message. At this
+       /// Flag which is set on ChannelReady or FundingSent after sending a shutdown message. At this
        /// point, we may not add any new HTLCs to the channel.
        LocalShutdownSent = 1 << 11,
        /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
@@ -439,8 +439,6 @@ pub(super) struct ReestablishResponses {
        pub raa: Option<msgs::RevokeAndACK>,
        pub commitment_update: Option<msgs::CommitmentUpdate>,
        pub order: RAACommitmentOrder,
-       pub mon_update: Option<ChannelMonitorUpdate>,
-       pub holding_cell_failed_htlcs: Vec<(HTLCSource, PaymentHash)>,
        pub announcement_sigs: Option<msgs::AnnouncementSignatures>,
        pub shutdown_msg: Option<msgs::Shutdown>,
 }
@@ -509,7 +507,7 @@ pub(super) struct Channel<Signer: Sign> {
 
        inbound_handshake_limits_override: Option<ChannelHandshakeLimits>,
 
-       user_id: u64,
+       user_id: u128,
 
        channel_id: [u8; 32],
        channel_state: u32,
@@ -736,6 +734,9 @@ pub(super) struct Channel<Signer: Sign> {
        // don't currently support node id aliases and eventually privacy should be provided with
        // blinded paths instead of simple scid+node_id aliases.
        outbound_scid_alias: u64,
+
+       // We track whether we already emitted a `ChannelReady` event.
+       channel_ready_event_emitted: bool,
 }
 
 #[cfg(any(test, fuzzing))]
@@ -899,7 +900,7 @@ impl<Signer: Sign> Channel<Signer> {
        // Constructors:
        pub fn new_outbound<K: Deref, F: Deref>(
                fee_estimator: &LowerBoundedFeeEstimator<F>, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
-               channel_value_satoshis: u64, push_msat: u64, user_id: u64, config: &UserConfig, current_chain_height: u32,
+               channel_value_satoshis: u64, push_msat: u64, user_id: u128, config: &UserConfig, current_chain_height: u32,
                outbound_scid_alias: u64
        ) -> Result<Channel<Signer>, APIError>
        where K::Target: KeysInterface<Signer = Signer>,
@@ -1037,6 +1038,7 @@ impl<Signer: Sign> Channel<Signer> {
                                counterparty_parameters: None,
                                funding_outpoint: None,
                                opt_anchors: if opt_anchors { Some(()) } else { None },
+                               opt_non_zero_fee_anchors: None
                        },
                        funding_transaction: None,
 
@@ -1063,6 +1065,8 @@ impl<Signer: Sign> Channel<Signer> {
                        latest_inbound_scid_alias: None,
                        outbound_scid_alias,
 
+                       channel_ready_event_emitted: false,
+
                        #[cfg(any(test, fuzzing))]
                        historical_inbound_htlc_fulfills: HashSet::new(),
 
@@ -1070,8 +1074,9 @@ impl<Signer: Sign> Channel<Signer> {
                })
        }
 
-       fn check_remote_fee<F: Deref>(fee_estimator: &LowerBoundedFeeEstimator<F>, feerate_per_kw: u32) -> Result<(), ChannelError>
-               where F::Target: FeeEstimator
+       fn check_remote_fee<F: Deref, L: Deref>(fee_estimator: &LowerBoundedFeeEstimator<F>,
+               feerate_per_kw: u32, cur_feerate_per_kw: Option<u32>, logger: &L)
+               -> Result<(), ChannelError> where F::Target: FeeEstimator, L::Target: Logger,
        {
                // We only bound the fee updates on the upper side to prevent completely absurd feerates,
                // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
@@ -1088,6 +1093,14 @@ impl<Signer: Sign> Channel<Signer> {
                // of 1.1 sat/vbyte and a receiver that wants 1.1 rounded up to 2. Thus, we always add 250
                // sat/kw before the comparison here.
                if feerate_per_kw + 250 < lower_limit {
+                       if let Some(cur_feerate) = cur_feerate_per_kw {
+                               if feerate_per_kw > cur_feerate {
+                                       log_warn!(logger,
+                                               "Accepting feerate that may prevent us from closing this channel because it's higher than what we have now. Had {} s/kW, now {} s/kW.",
+                                               cur_feerate, feerate_per_kw);
+                                       return Ok(());
+                               }
+                       }
                        return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {} (- 250)", feerate_per_kw, lower_limit)));
                }
                Ok(())
@@ -1097,7 +1110,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// Assumes chain_hash has already been checked and corresponds with what we expect!
        pub fn new_from_req<K: Deref, F: Deref, L: Deref>(
                fee_estimator: &LowerBoundedFeeEstimator<F>, keys_provider: &K, counterparty_node_id: PublicKey, their_features: &InitFeatures,
-               msg: &msgs::OpenChannel, user_id: u64, config: &UserConfig, current_chain_height: u32, logger: &L,
+               msg: &msgs::OpenChannel, user_id: u128, config: &UserConfig, current_chain_height: u32, logger: &L,
                outbound_scid_alias: u64
        ) -> Result<Channel<Signer>, ChannelError>
                where K::Target: KeysInterface<Signer = Signer>,
@@ -1174,7 +1187,7 @@ impl<Signer: Sign> Channel<Signer> {
                if msg.htlc_minimum_msat >= full_channel_value_msat {
                        return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
                }
-               Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
+               Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw, None, logger)?;
 
                let max_counterparty_selected_contest_delay = u16::min(config.channel_handshake_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
                if msg.to_self_delay > max_counterparty_selected_contest_delay {
@@ -1371,6 +1384,7 @@ impl<Signer: Sign> Channel<Signer> {
                                }),
                                funding_outpoint: None,
                                opt_anchors: if opt_anchors { Some(()) } else { None },
+                               opt_non_zero_fee_anchors: None
                        },
                        funding_transaction: None,
 
@@ -1397,6 +1411,8 @@ impl<Signer: Sign> Channel<Signer> {
                        latest_inbound_scid_alias: None,
                        outbound_scid_alias,
 
+                       channel_ready_event_emitted: false,
+
                        #[cfg(any(test, fuzzing))]
                        historical_inbound_htlc_fulfills: HashSet::new(),
 
@@ -1733,27 +1749,27 @@ impl<Signer: Sign> Channel<Signer> {
        /// our counterparty!)
        /// The result is a transaction which we can revoke broadcastership of (ie a "local" transaction)
        /// TODO Some magic rust shit to compile-time check this?
-       fn build_holder_transaction_keys(&self, commitment_number: u64) -> Result<TxCreationKeys, ChannelError> {
+       fn build_holder_transaction_keys(&self, commitment_number: u64) -> TxCreationKeys {
                let per_commitment_point = self.holder_signer.get_per_commitment_point(commitment_number, &self.secp_ctx);
                let delayed_payment_base = &self.get_holder_pubkeys().delayed_payment_basepoint;
                let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
                let counterparty_pubkeys = self.get_counterparty_pubkeys();
 
-               Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint), "Local tx keys generation got bogus keys".to_owned()))
+               TxCreationKeys::derive_new(&self.secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint)
        }
 
        #[inline]
        /// 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> {
+       fn build_remote_transaction_keys(&self) -> TxCreationKeys {
                //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
                //may see payments to it!
                let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
                let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
                let counterparty_pubkeys = self.get_counterparty_pubkeys();
 
-               Ok(secp_check!(TxCreationKeys::derive_new(&self.secp_ctx, &self.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint), "Remote tx keys generation got bogus keys".to_owned()))
+               TxCreationKeys::derive_new(&self.secp_ctx, &self.counterparty_cur_commitment_point.unwrap(), &counterparty_pubkeys.delayed_payment_basepoint, &counterparty_pubkeys.htlc_basepoint, revocation_basepoint, htlc_basepoint)
        }
 
        /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
@@ -1786,11 +1802,11 @@ impl<Signer: Sign> Channel<Signer> {
        }
 
        fn get_update_fulfill_htlc<L: Deref>(&mut self, htlc_id_arg: u64, payment_preimage_arg: PaymentPreimage, logger: &L) -> UpdateFulfillFetch where L::Target: Logger {
-               // Either ChannelFunded got set (which means it won't be unset) or there is no way any
+               // Either ChannelReady 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,
                // either.
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
                }
                assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
@@ -1933,7 +1949,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// If we do fail twice, we debug_assert!(false) and return Ok(None). Thus, will always return
        /// Ok(_) if debug assertions are turned on or preconditions are met.
        pub fn get_update_fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, logger: &L) -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        panic!("Was asked to fail an HTLC when channel was not in an operational state");
                }
                assert_eq!(self.channel_state & ChannelState::ShutdownComplete as u32, 0);
@@ -2141,7 +2157,7 @@ impl<Signer: Sign> Channel<Signer> {
        fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(Txid, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
                let funding_script = self.get_funding_redeemscript();
 
-               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
+               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number);
                let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger).tx;
                {
                        let trusted_tx = initial_commitment_tx.trust();
@@ -2155,7 +2171,7 @@ impl<Signer: Sign> Channel<Signer> {
                        secp_check!(self.secp_ctx.verify_ecdsa(&sighash, &sig, self.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
                }
 
-               let counterparty_keys = self.build_remote_transaction_keys()?;
+               let counterparty_keys = self.build_remote_transaction_keys();
                let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
 
                let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
@@ -2269,7 +2285,7 @@ impl<Signer: Sign> Channel<Signer> {
 
                let funding_script = self.get_funding_redeemscript();
 
-               let counterparty_keys = self.build_remote_transaction_keys()?;
+               let counterparty_keys = self.build_remote_transaction_keys();
                let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
                let counterparty_trusted_tx = counterparty_initial_commitment_tx.trust();
                let counterparty_initial_bitcoin_tx = counterparty_trusted_tx.built_transaction();
@@ -2277,7 +2293,7 @@ impl<Signer: Sign> Channel<Signer> {
                log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
                        log_bytes!(self.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
 
-               let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
+               let holder_signer = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number);
                let initial_commitment_tx = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).tx;
                {
                        let trusted_tx = initial_commitment_tx.trust();
@@ -2349,9 +2365,9 @@ impl<Signer: Sign> Channel<Signer> {
                if non_shutdown_state == ChannelState::FundingSent as u32 {
                        self.channel_state |= ChannelState::TheirChannelReady as u32;
                } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
-                       self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
+                       self.channel_state = ChannelState::ChannelReady as u32 | (self.channel_state & MULTI_STATE_FLAGS);
                        self.update_time_counter += 1;
-               } else if self.channel_state & (ChannelState::ChannelFunded as u32) != 0 ||
+               } else if self.channel_state & (ChannelState::ChannelReady as u32) != 0 ||
                        // If we reconnected before sending our `channel_ready` they may still resend theirs:
                        (self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) ==
                                              (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32))
@@ -2712,12 +2728,12 @@ impl<Signer: Sign> Channel<Signer> {
        pub fn update_add_htlc<F, L: Deref>(&mut self, msg: &msgs::UpdateAddHTLC, mut pending_forward_status: PendingHTLCStatus, create_pending_htlc_status: F, logger: &L) -> Result<(), ChannelError>
        where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus, L::Target: Logger {
                // We can't accept HTLCs sent after we've sent a shutdown.
-               let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
+               let local_sent_shutdown = (self.channel_state & (ChannelState::ChannelReady as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelReady as u32);
                if local_sent_shutdown {
                        pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
                }
                // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
-               let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelFunded as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelFunded as u32);
+               let remote_sent_shutdown = (self.channel_state & (ChannelState::ChannelReady as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelReady as u32);
                if remote_sent_shutdown {
                        return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
                }
@@ -2894,7 +2910,7 @@ impl<Signer: Sign> Channel<Signer> {
        }
 
        pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
                }
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
@@ -2905,7 +2921,7 @@ impl<Signer: Sign> Channel<Signer> {
        }
 
        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) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
                }
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
@@ -2917,7 +2933,7 @@ impl<Signer: Sign> Channel<Signer> {
        }
 
        pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
                }
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
@@ -2931,7 +2947,7 @@ impl<Signer: Sign> Channel<Signer> {
        pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<(msgs::RevokeAndACK, Option<msgs::CommitmentSigned>, ChannelMonitorUpdate), (Option<ChannelMonitorUpdate>, ChannelError)>
                where L::Target: Logger
        {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        return Err((None, ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned())));
                }
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
@@ -2943,7 +2959,7 @@ impl<Signer: Sign> Channel<Signer> {
 
                let funding_script = self.get_funding_redeemscript();
 
-               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number).map_err(|e| (None, e))?;
+               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number);
 
                let commitment_stats = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, false, logger);
                let commitment_txid = {
@@ -3002,7 +3018,7 @@ impl<Signer: Sign> Channel<Signer> {
                        if let Some(_) = htlc.transaction_output_index {
                                let htlc_tx = chan_utils::build_htlc_transaction(&commitment_txid, commitment_stats.feerate_per_kw,
                                        self.get_counterparty_selected_contest_delay().unwrap(), &htlc, self.opt_anchors(),
-                                       &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
+                                       false, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
 
                                let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, self.opt_anchors(), &keys);
                                let htlc_sighashtype = if self.opt_anchors() { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };
@@ -3124,7 +3140,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// If we're not in a state where freeing the holding cell makes sense, this is a no-op and
        /// returns `(None, Vec::new())`.
        pub fn maybe_free_holding_cell_htlcs<L: Deref>(&mut self, logger: &L) -> Result<(Option<(msgs::CommitmentUpdate, ChannelMonitorUpdate)>, Vec<(HTLCSource, PaymentHash)>), ChannelError> where L::Target: Logger {
-               if self.channel_state >= ChannelState::ChannelFunded as u32 &&
+               if self.channel_state >= ChannelState::ChannelReady as u32 &&
                   (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) == 0 {
                        self.free_holding_cell_htlcs(logger)
                } else { Ok((None, Vec::new())) }
@@ -3252,7 +3268,7 @@ impl<Signer: Sign> Channel<Signer> {
        pub fn revoke_and_ack<L: Deref>(&mut self, msg: &msgs::RevokeAndACK, logger: &L) -> Result<RAAUpdates, ChannelError>
                where L::Target: Logger,
        {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
                }
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
@@ -3535,7 +3551,7 @@ impl<Signer: Sign> Channel<Signer> {
                // Before proposing a feerate update, check that we can actually afford the new fee.
                let inbound_stats = self.get_inbound_pending_htlc_stats(Some(feerate_per_kw));
                let outbound_stats = self.get_outbound_pending_htlc_stats(Some(feerate_per_kw));
-               let keys = if let Ok(keys) = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number) { keys } else { return None; };
+               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number);
                let commitment_stats = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger);
                let buffer_fee_msat = Channel::<Signer>::commit_tx_fee_sat(feerate_per_kw, commitment_stats.num_nondust_htlcs + outbound_stats.on_holder_tx_holding_cell_htlcs_count as usize + CONCURRENT_INBOUND_HTLC_FEE_BUFFER as usize, self.opt_anchors()) * 1000;
                let holder_balance_msat = commitment_stats.local_balance_msat - outbound_stats.holding_cell_msat;
@@ -3696,7 +3712,7 @@ impl<Signer: Sign> Channel<Signer> {
                        } else { None };
                // That said, if the funding transaction is already confirmed (ie we're active with a
                // minimum_depth over 0) don't bother re-broadcasting the confirmed funding tx.
-               if self.channel_state & !MULTI_STATE_FLAGS >= ChannelState::ChannelFunded as u32 && self.minimum_depth != Some(0) {
+               if self.channel_state & !MULTI_STATE_FLAGS >= ChannelState::ChannelReady as u32 && self.minimum_depth != Some(0) {
                        funding_broadcastable = None;
                }
 
@@ -3755,8 +3771,8 @@ impl<Signer: Sign> Channel<Signer> {
                }
        }
 
-       pub fn update_fee<F: Deref>(&mut self, fee_estimator: &LowerBoundedFeeEstimator<F>, msg: &msgs::UpdateFee) -> Result<(), ChannelError>
-               where F::Target: FeeEstimator
+       pub fn update_fee<F: Deref, L: Deref>(&mut self, fee_estimator: &LowerBoundedFeeEstimator<F>, msg: &msgs::UpdateFee, logger: &L) -> Result<(), ChannelError>
+               where F::Target: FeeEstimator, L::Target: Logger
        {
                if self.is_outbound() {
                        return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
@@ -3764,7 +3780,7 @@ impl<Signer: Sign> Channel<Signer> {
                if self.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
                        return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
                }
-               Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw)?;
+               Channel::<Signer>::check_remote_fee(fee_estimator, msg.feerate_per_kw, Some(self.feerate_per_kw), logger)?;
                let feerate_over_dust_buffer = msg.feerate_per_kw > self.get_dust_buffer_feerate(None);
 
                self.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
@@ -3948,9 +3964,8 @@ impl<Signer: Sign> Channel<Signer> {
                                // Short circuit the whole handler as there is nothing we can resend them
                                return Ok(ReestablishResponses {
                                        channel_ready: None,
-                                       raa: None, commitment_update: None, mon_update: None,
+                                       raa: None, commitment_update: None,
                                        order: RAACommitmentOrder::CommitmentFirst,
-                                       holding_cell_failed_htlcs: Vec::new(),
                                        shutdown_msg, announcement_sigs,
                                });
                        }
@@ -3963,9 +3978,8 @@ impl<Signer: Sign> Channel<Signer> {
                                        next_per_commitment_point,
                                        short_channel_id_alias: Some(self.outbound_scid_alias),
                                }),
-                               raa: None, commitment_update: None, mon_update: None,
+                               raa: None, commitment_update: None,
                                order: RAACommitmentOrder::CommitmentFirst,
-                               holding_cell_failed_htlcs: Vec::new(),
                                shutdown_msg, announcement_sigs,
                        });
                }
@@ -4008,46 +4022,12 @@ impl<Signer: Sign> Channel<Signer> {
                                log_debug!(logger, "Reconnected channel {} with no loss", log_bytes!(self.channel_id()));
                        }
 
-                       if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) == 0 {
-                               // We're up-to-date and not waiting on a remote revoke (if we are our
-                               // channel_reestablish should result in them sending a revoke_and_ack), but we may
-                               // have received some updates while we were disconnected. Free the holding cell
-                               // now!
-                               match self.free_holding_cell_htlcs(logger) {
-                                       Err(ChannelError::Close(msg)) => Err(ChannelError::Close(msg)),
-                                       Err(ChannelError::Warn(_)) | Err(ChannelError::Ignore(_)) =>
-                                               panic!("Got non-channel-failing result from free_holding_cell_htlcs"),
-                                       Ok((Some((commitment_update, monitor_update)), holding_cell_failed_htlcs)) => {
-                                               Ok(ReestablishResponses {
-                                                       channel_ready, shutdown_msg, announcement_sigs,
-                                                       raa: required_revoke,
-                                                       commitment_update: Some(commitment_update),
-                                                       order: self.resend_order.clone(),
-                                                       mon_update: Some(monitor_update),
-                                                       holding_cell_failed_htlcs,
-                                               })
-                                       },
-                                       Ok((None, holding_cell_failed_htlcs)) => {
-                                               Ok(ReestablishResponses {
-                                                       channel_ready, shutdown_msg, announcement_sigs,
-                                                       raa: required_revoke,
-                                                       commitment_update: None,
-                                                       order: self.resend_order.clone(),
-                                                       mon_update: None,
-                                                       holding_cell_failed_htlcs,
-                                               })
-                                       },
-                               }
-                       } else {
-                               Ok(ReestablishResponses {
-                                       channel_ready, shutdown_msg, announcement_sigs,
-                                       raa: required_revoke,
-                                       commitment_update: None,
-                                       order: self.resend_order.clone(),
-                                       mon_update: None,
-                                       holding_cell_failed_htlcs: Vec::new(),
-                               })
-                       }
+                       Ok(ReestablishResponses {
+                               channel_ready, shutdown_msg, announcement_sigs,
+                               raa: required_revoke,
+                               commitment_update: None,
+                               order: self.resend_order.clone(),
+                       })
                } else if msg.next_local_commitment_number == next_counterparty_commitment_number - 1 {
                        if required_revoke.is_some() {
                                log_debug!(logger, "Reconnected channel {} with lost outbound RAA and lost remote commitment tx", log_bytes!(self.channel_id()));
@@ -4059,9 +4039,8 @@ impl<Signer: Sign> Channel<Signer> {
                                self.monitor_pending_commitment_signed = true;
                                Ok(ReestablishResponses {
                                        channel_ready, shutdown_msg, announcement_sigs,
-                                       commitment_update: None, raa: None, mon_update: None,
+                                       commitment_update: None, raa: None,
                                        order: self.resend_order.clone(),
-                                       holding_cell_failed_htlcs: Vec::new(),
                                })
                        } else {
                                Ok(ReestablishResponses {
@@ -4069,8 +4048,6 @@ impl<Signer: Sign> Channel<Signer> {
                                        raa: required_revoke,
                                        commitment_update: Some(self.get_last_commitment_update(logger)),
                                        order: self.resend_order.clone(),
-                                       mon_update: None,
-                                       holding_cell_failed_htlcs: Vec::new(),
                                })
                        }
                } else {
@@ -4198,7 +4175,7 @@ impl<Signer: Sign> Channel<Signer> {
        pub fn shutdown<K: Deref>(
                &mut self, keys_provider: &K, their_features: &InitFeatures, msg: &msgs::Shutdown
        ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
-       where K::Target: KeysInterface<Signer = Signer>
+       where K::Target: KeysInterface
        {
                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".to_owned()));
@@ -4475,7 +4452,7 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// Gets the "user_id" value passed into the construction of this channel. It has no special
        /// meaning and exists only to allow users to have a persistent identifier of a channel.
-       pub fn get_user_id(&self) -> u64 {
+       pub fn get_user_id(&self) -> u128 {
                self.user_id
        }
 
@@ -4513,6 +4490,21 @@ impl<Signer: Sign> Channel<Signer> {
                self.channel_transaction_parameters.funding_outpoint
        }
 
+       /// Returns the block hash in which our funding transaction was confirmed.
+       pub fn get_funding_tx_confirmed_in(&self) -> Option<BlockHash> {
+               self.funding_tx_confirmed_in
+       }
+
+       /// Returns the current number of confirmations on the funding transaction.
+       pub fn get_funding_tx_confirmations(&self, height: u32) -> u32 {
+               if self.funding_tx_confirmation_height == 0 {
+                       // We either haven't seen any confirmation yet, or observed a reorg.
+                       return 0;
+               }
+
+               height.checked_sub(self.funding_tx_confirmation_height).map_or(0, |c| c + 1)
+       }
+
        fn get_holder_selected_contest_delay(&self) -> u16 {
                self.channel_transaction_parameters.holder_selected_contest_delay
        }
@@ -4598,6 +4590,16 @@ impl<Signer: Sign> Channel<Signer> {
                self.prev_config.map(|prev_config| prev_config.0)
        }
 
+       // Checks whether we should emit a `ChannelReady` event.
+       pub(crate) fn should_emit_channel_ready_event(&mut self) -> bool {
+               self.is_usable() && !self.channel_ready_event_emitted
+       }
+
+       // Remembers that we already emitted a `ChannelReady` event.
+       pub(crate) fn set_channel_ready_event_emitted(&mut self) {
+               self.channel_ready_event_emitted = true;
+       }
+
        /// Tracks the number of ticks elapsed since the previous [`ChannelConfig`] was updated. Once
        /// [`EXPIRE_PREV_CONFIG_TICKS`] is reached, the previous config is considered expired and will
        /// no longer be considered when forwarding HTLCs.
@@ -4766,8 +4768,8 @@ impl<Signer: Sign> Channel<Signer> {
        /// Returns true if this channel is fully established and not known to be closing.
        /// Allowed in any state (including after shutdown)
        pub fn is_usable(&self) -> bool {
-               let mask = ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK;
-               (self.channel_state & mask) == (ChannelState::ChannelFunded as u32) && !self.monitor_pending_channel_ready
+               let mask = ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK;
+               (self.channel_state & mask) == (ChannelState::ChannelReady as u32) && !self.monitor_pending_channel_ready
        }
 
        /// Returns true if this channel is currently available for use. This is a superset of
@@ -4826,7 +4828,7 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// Returns true if our channel_ready has been sent
        pub fn is_our_channel_ready(&self) -> bool {
-               (self.channel_state & ChannelState::OurChannelReady as u32) != 0 || self.channel_state >= ChannelState::ChannelFunded as u32
+               (self.channel_state & ChannelState::OurChannelReady as u32) != 0 || self.channel_state >= ChannelState::ChannelReady as u32
        }
 
        /// Returns true if our peer has either initiated or agreed to shut down the channel.
@@ -4880,14 +4882,14 @@ impl<Signer: Sign> Channel<Signer> {
                        self.channel_state |= ChannelState::OurChannelReady as u32;
                        true
                } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) {
-                       self.channel_state = ChannelState::ChannelFunded as u32 | (self.channel_state & MULTI_STATE_FLAGS);
+                       self.channel_state = ChannelState::ChannelReady as u32 | (self.channel_state & MULTI_STATE_FLAGS);
                        self.update_time_counter += 1;
                        true
                } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
                        // We got a reorg but not enough to trigger a force close, just ignore.
                        false
                } else {
-                       if self.funding_tx_confirmation_height != 0 && self.channel_state < ChannelState::ChannelFunded as u32 {
+                       if self.funding_tx_confirmation_height != 0 && self.channel_state < ChannelState::ChannelReady as u32 {
                                // We should never see a funding transaction on-chain until we've received
                                // funding_signed (if we're an outbound channel), or seen funding_generated (if we're
                                // an inbound channel - before that we have no known funding TXID). The fuzzer,
@@ -5031,7 +5033,7 @@ impl<Signer: Sign> Channel<Signer> {
                }
 
                let non_shutdown_state = self.channel_state & (!MULTI_STATE_FLAGS);
-               if non_shutdown_state >= ChannelState::ChannelFunded as u32 ||
+               if non_shutdown_state >= ChannelState::ChannelReady as u32 ||
                   (non_shutdown_state & ChannelState::OurChannelReady as u32) == ChannelState::OurChannelReady as u32 {
                        let mut funding_tx_confirmations = height as i64 - self.funding_tx_confirmation_height as i64 + 1;
                        if self.funding_tx_confirmation_height == 0 {
@@ -5059,7 +5061,7 @@ impl<Signer: Sign> Channel<Signer> {
                                height >= self.channel_creation_height + FUNDING_CONF_DEADLINE_BLOCKS {
                        log_info!(logger, "Closing channel {} due to funding timeout", log_bytes!(self.channel_id));
                        // If funding_tx_confirmed_in is unset, the channel must not be active
-                       assert!(non_shutdown_state <= ChannelState::ChannelFunded as u32);
+                       assert!(non_shutdown_state <= ChannelState::ChannelReady as u32);
                        assert_eq!(non_shutdown_state & ChannelState::OurChannelReady as u32, 0);
                        return Err(ClosureReason::FundingTimedOut);
                }
@@ -5156,7 +5158,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// should be sent back to the counterparty node.
        ///
        /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
-       pub fn accept_inbound_channel(&mut self, user_id: u64) -> msgs::AcceptChannel {
+       pub fn accept_inbound_channel(&mut self, user_id: u128) -> msgs::AcceptChannel {
                if self.is_outbound() {
                        panic!("Tried to send accept_channel for an outbound channel?");
                }
@@ -5219,7 +5221,7 @@ impl<Signer: Sign> Channel<Signer> {
 
        /// If an Err is returned, it is a ChannelError::Close (for get_outbound_funding_created)
        fn get_outbound_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
-               let counterparty_keys = self.build_remote_transaction_keys()?;
+               let counterparty_keys = self.build_remote_transaction_keys();
                let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
                Ok(self.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.secp_ctx)
                                .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
@@ -5484,7 +5486,7 @@ impl<Signer: Sign> Channel<Signer> {
        ///
        /// If an Err is returned, it's a ChannelError::Ignore!
        pub fn send_htlc<L: Deref>(&mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource, onion_routing_packet: msgs::OnionPacket, logger: &L) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError> where L::Target: Logger {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelReady as u32) {
                        return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
                }
                let channel_total_msat = self.channel_value_satoshis * 1000;
@@ -5520,7 +5522,7 @@ impl<Signer: Sign> Channel<Signer> {
                        return Err(ChannelError::Ignore(format!("Cannot send value that would put us over the max HTLC value in flight our peer will accept ({})", self.counterparty_max_htlc_value_in_flight_msat)));
                }
 
-               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number)?;
+               let keys = self.build_holder_transaction_keys(self.cur_holder_commitment_transaction_number);
                let commitment_stats = self.build_commitment_transaction(self.cur_holder_commitment_transaction_number, &keys, true, true, logger);
                if !self.is_outbound() {
                        // Check that we won't violate the remote channel reserve by adding this HTLC.
@@ -5617,7 +5619,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// 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<L: Deref>(&mut self, logger: &L) -> Result<(msgs::CommitmentSigned, ChannelMonitorUpdate), ChannelError> where L::Target: Logger {
-               if (self.channel_state & (ChannelState::ChannelFunded as u32)) != (ChannelState::ChannelFunded as u32) {
+               if (self.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
                        panic!("Cannot create commitment tx until channel is fully established");
                }
                if (self.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == (ChannelState::AwaitingRemoteRevoke as u32) {
@@ -5712,7 +5714,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// 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<L: Deref>(&self, logger: &L) -> Result<(msgs::CommitmentSigned, (Txid, Vec<(HTLCOutputInCommitment, Option<&HTLCSource>)>)), ChannelError> where L::Target: Logger {
-               let counterparty_keys = self.build_remote_transaction_keys()?;
+               let counterparty_keys = self.build_remote_transaction_keys();
                let commitment_stats = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, true, logger);
                let counterparty_commitment_txid = commitment_stats.tx.trust().txid();
                let (signature, htlc_signatures);
@@ -5753,7 +5755,7 @@ impl<Signer: Sign> Channel<Signer> {
 
                        for (ref htlc_sig, ref htlc) in htlc_signatures.iter().zip(htlcs) {
                                log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
-                                       encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, commitment_stats.feerate_per_kw, self.get_holder_selected_contest_delay(), htlc, self.opt_anchors(), &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
+                                       encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, commitment_stats.feerate_per_kw, self.get_holder_selected_contest_delay(), htlc, self.opt_anchors(), false, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
                                        encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, self.opt_anchors(), &counterparty_keys)),
                                        log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
                                        log_bytes!(htlc_sig.serialize_compact()[..]), log_bytes!(self.channel_id()));
@@ -5803,7 +5805,7 @@ impl<Signer: Sign> Channel<Signer> {
        /// holding cell HTLCs for payment failure.
        pub fn get_shutdown<K: Deref>(&mut self, keys_provider: &K, their_features: &InitFeatures, target_feerate_sats_per_kw: Option<u32>)
        -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
-       where K::Target: KeysInterface<Signer = Signer> {
+       where K::Target: KeysInterface {
                for htlc in self.pending_outbound_htlcs.iter() {
                        if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
                                return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
@@ -5906,7 +5908,7 @@ impl<Signer: Sign> Channel<Signer> {
                        // funding transaction, don't return a funding txo (which prevents providing the
                        // monitor update to the user, even if we return one).
                        // See test_duplicate_chan_id and test_pre_lockin_no_chan_closed_update for more.
-                       if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelFunded as u32 | ChannelState::ShutdownComplete as u32) != 0 {
+                       if self.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelReady as u32 | ChannelState::ShutdownComplete as u32) != 0 {
                                self.latest_monitor_update_id += 1;
                                Some((funding_txo, ChannelMonitorUpdate {
                                        update_id: self.latest_monitor_update_id,
@@ -5919,6 +5921,17 @@ impl<Signer: Sign> Channel<Signer> {
                self.update_time_counter += 1;
                (monitor_update, dropped_outbound_htlcs)
        }
+
+       pub fn inflight_htlc_sources(&self) -> impl Iterator<Item=&HTLCSource> {
+               self.holding_cell_htlc_updates.iter()
+                       .flat_map(|htlc_update| {
+                               match htlc_update {
+                                       HTLCUpdateAwaitingACK::AddHTLC { source, .. } => { Some(source) }
+                                       _ => None
+                               }
+                       })
+                       .chain(self.pending_outbound_htlcs.iter().map(|htlc| &htlc.source))
+       }
 }
 
 const SERIALIZATION_VERSION: u8 = 2;
@@ -5985,7 +5998,11 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 
                write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
 
-               self.user_id.write(writer)?;
+               // `user_id` used to be a single u64 value. In order to remain backwards compatible with
+               // versions prior to 0.0.113, the u128 is serialized as two separate u64 values. We write
+               // the low bytes now and the optional high bytes later.
+               let user_id_low = self.user_id as u64;
+               user_id_low.write(writer)?;
 
                // Version 1 deserializers expected to read parts of the config object here. Version 2
                // deserializers (0.0.99) now read config through TLVs, and as we now require them for
@@ -6230,6 +6247,13 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
                        if self.holder_max_htlc_value_in_flight_msat != Self::get_holder_max_htlc_value_in_flight_msat(self.channel_value_satoshis, &old_max_in_flight_percent_config)
                        { Some(self.holder_max_htlc_value_in_flight_msat) } else { None };
 
+               let channel_ready_event_emitted = Some(self.channel_ready_event_emitted);
+
+               // `user_id` used to be a single u64 value. In order to remain backwards compatible with
+               // versions prior to 0.0.113, the u128 is serialized as two separate u64 values. Therefore,
+               // we write the high bytes as an option here.
+               let user_id_high_opt = Some((self.user_id >> 64) as u64);
+
                write_tlv_fields!(writer, {
                        (0, self.announcement_sigs, option),
                        // minimum_depth and counterparty_selected_channel_reserve_satoshis used to have a
@@ -6252,6 +6276,8 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
                        (17, self.announcement_sigs_state, required),
                        (19, self.latest_inbound_scid_alias, option),
                        (21, self.outbound_scid_alias, required),
+                       (23, channel_ready_event_emitted, option),
+                       (25, user_id_high_opt, option),
                });
 
                Ok(())
@@ -6259,13 +6285,16 @@ impl<Signer: Sign> Writeable for Channel<Signer> {
 }
 
 const MAX_ALLOC_SIZE: usize = 64*1024;
-impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
-               where K::Target: KeysInterface<Signer = Signer> {
+impl<'a, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<<K::Target as KeysInterface>::Signer>
+               where K::Target: KeysInterface {
        fn read<R : io::Read>(reader: &mut R, args: (&'a K, u32)) -> Result<Self, DecodeError> {
                let (keys_source, serialized_height) = args;
                let ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
 
-               let user_id = Readable::read(reader)?;
+               // `user_id` used to be a single u64 value. In order to remain backwards compatible with
+               // versions prior to 0.0.113, the u128 is serialized as two separate u64 values. We read
+               // the low bytes now and the high bytes later.
+               let user_id_low: u64 = Readable::read(reader)?;
 
                let mut config = Some(LegacyChannelConfig::default());
                if ver == 1 {
@@ -6509,6 +6538,9 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
                let mut announcement_sigs_state = Some(AnnouncementSigsState::NotSent);
                let mut latest_inbound_scid_alias = None;
                let mut outbound_scid_alias = None;
+               let mut channel_ready_event_emitted = None;
+
+               let mut user_id_high_opt: Option<u64> = None;
 
                read_tlv_fields!(reader, {
                        (0, announcement_sigs, option),
@@ -6526,6 +6558,8 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
                        (17, announcement_sigs_state, option),
                        (19, latest_inbound_scid_alias, option),
                        (21, outbound_scid_alias, option),
+                       (23, channel_ready_event_emitted, option),
+                       (25, user_id_high_opt, option),
                });
 
                if let Some(preimages) = preimages_opt {
@@ -6562,6 +6596,11 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
                let mut secp_ctx = Secp256k1::new();
                secp_ctx.seeded_randomize(&keys_source.get_secure_random_bytes());
 
+               // `user_id` used to be a single u64 value. In order to remain backwards
+               // compatible with versions prior to 0.0.113, the u128 is serialized as two
+               // separate u64 values.
+               let user_id = user_id_low as u128 + ((user_id_high_opt.unwrap_or(0) as u128) << 64);
+
                Ok(Channel {
                        user_id,
 
@@ -6666,6 +6705,8 @@ impl<'a, Signer: Sign, K: Deref> ReadableArgs<(&'a K, u32)> for Channel<Signer>
                        // Later in the ChannelManager deserialization phase we scan for channels and assign scid aliases if its missing
                        outbound_scid_alias: outbound_scid_alias.unwrap_or(0),
 
+                       channel_ready_event_emitted: channel_ready_event_emitted.unwrap_or(true),
+
                        #[cfg(any(test, fuzzing))]
                        historical_inbound_htlc_fulfills,
 
@@ -6736,7 +6777,8 @@ mod tests {
                // arithmetic, causing a panic with debug assertions enabled.
                let fee_est = TestFeeEstimator { fee_est: 42 };
                let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_est);
-               assert!(Channel::<InMemorySigner>::check_remote_fee(&bounded_fee_estimator, u32::max_value()).is_err());
+               assert!(Channel::<InMemorySigner>::check_remote_fee(&bounded_fee_estimator,
+                       u32::max_value(), None, &&test_utils::TestLogger::new()).is_err());
        }
 
        struct Keys {
@@ -7220,7 +7262,7 @@ mod tests {
                        // These aren't set in the test vectors:
                        [0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
                        10_000_000,
-                       [0; 32]
+                       [0; 32],
                );
 
                assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
@@ -7267,7 +7309,7 @@ mod tests {
                let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
                let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
                let htlc_basepoint = &chan.holder_signer.pubkeys().htlc_basepoint;
-               let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint).unwrap();
+               let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint);
 
                macro_rules! test_commitment {
                        ( $counterparty_sig_hex: expr, $sig_hex: expr, $tx_hex: expr, $($remain:tt)* ) => {
@@ -7338,7 +7380,7 @@ mod tests {
                                        let ref htlc = htlcs[$htlc_idx];
                                        let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.feerate_per_kw,
                                                chan.get_counterparty_selected_contest_delay().unwrap(),
-                                               &htlc, $opt_anchors, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
+                                               &htlc, $opt_anchors, false, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
                                        let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, $opt_anchors, &keys);
                                        let htlc_sighashtype = if $opt_anchors { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };
                                        let htlc_sighash = Message::from_slice(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, htlc_sighashtype).unwrap()[..]).unwrap();
@@ -7920,16 +7962,16 @@ mod tests {
                let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
                assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
 
-               assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
+               assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).serialize()[..],
                                hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
 
-               assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret).unwrap(),
+               assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret),
                                SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
 
-               assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).unwrap().serialize()[..],
+               assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).serialize()[..],
                                hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
 
-               assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret).unwrap(),
+               assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret),
                                SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
        }