Document nonzero anchors in features module.
[rust-lightning] / lightning / src / ln / channel.rs
index 7e983fa7788643b30407aaf55303d5fb5165f91f..c6fd47ebcc8d6e24fc243f3553c560ee97d17aa6 100644 (file)
@@ -374,6 +374,16 @@ impl fmt::Debug for ChannelError {
        }
 }
 
+impl fmt::Display for ChannelError {
+       fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+               match self {
+                       &ChannelError::Ignore(ref e) => write!(f, "{}", e),
+                       &ChannelError::Warn(ref e) => write!(f, "{}", e),
+                       &ChannelError::Close(ref e) => write!(f, "{}", e),
+               }
+       }
+}
+
 macro_rules! secp_check {
        ($res: expr, $err: expr) => {
                match $res {
@@ -1412,7 +1422,7 @@ impl<Signer: ChannelSigner> ChannelContext<Signer> {
 
        /// Gets the redeemscript for the funding transaction output (ie the funding transaction output
        /// pays to get_funding_redeemscript().to_v0_p2wsh()).
-       /// Panics if called before accept_channel/new_from_req
+       /// Panics if called before accept_channel/InboundV1Channel::new
        pub fn get_funding_redeemscript(&self) -> Script {
                make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
        }
@@ -1874,6 +1884,52 @@ impl<Signer: ChannelSigner> ChannelContext<Signer> {
                        None
                }
        }
+
+       /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
+       /// shutdown of this channel - no more calls into this Channel may be made afterwards except
+       /// 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, should_broadcast: bool) -> ShutdownResult {
+               // Note that we MUST only generate a monitor update that indicates force-closure - we're
+               // called during initialization prior to the chain_monitor in the encompassing ChannelManager
+               // being fully configured in some cases. Thus, its likely any monitor events we generate will
+               // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
+               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
+               // return them to fail the payment.
+               let mut dropped_outbound_htlcs = Vec::with_capacity(self.holding_cell_htlc_updates.len());
+               let counterparty_node_id = self.get_counterparty_node_id();
+               for htlc_update in self.holding_cell_htlc_updates.drain(..) {
+                       match htlc_update {
+                               HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
+                                       dropped_outbound_htlcs.push((source, payment_hash, counterparty_node_id, self.channel_id));
+                               },
+                               _ => {}
+                       }
+               }
+               let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
+                       // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
+                       // returning a channel monitor update here would imply a channel monitor update before
+                       // we even registered the channel monitor to begin with, which is invalid.
+                       // Thus, if we aren't actually at a point where we could conceivably broadcast the
+                       // 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::ChannelReady as u32 | ChannelState::ShutdownComplete as u32) != 0 {
+                               self.latest_monitor_update_id = CLOSED_CHANNEL_UPDATE_ID;
+                               Some((self.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
+                                       update_id: self.latest_monitor_update_id,
+                                       updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
+                               }))
+                       } else { None }
+               } else { None };
+
+               self.channel_state = ChannelState::ShutdownComplete as u32;
+               self.update_time_counter += 1;
+               (monitor_update, dropped_outbound_htlcs)
+       }
 }
 
 // Internal utility functions for channels
@@ -1954,38 +2010,6 @@ struct CommitmentTxInfoCached {
 }
 
 impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
-       /// If we receive an error message, it may only be a rejection of the channel type we tried,
-       /// not of our ability to open any channel at all. Thus, on error, we should first call this
-       /// and see if we get a new `OpenChannel` message, otherwise the channel is failed.
-       pub(crate) fn maybe_handle_error_without_close(&mut self, chain_hash: BlockHash) -> Result<msgs::OpenChannel, ()> {
-               if !self.context.is_outbound() || self.context.channel_state != ChannelState::OurInitSent as u32 { return Err(()); }
-               if self.context.channel_type == ChannelTypeFeatures::only_static_remote_key() {
-                       // We've exhausted our options
-                       return Err(());
-               }
-               // We support opening a few different types of channels. Try removing our additional
-               // features one by one until we've either arrived at our default or the counterparty has
-               // accepted one.
-               //
-               // Due to the order below, we may not negotiate `option_anchors_zero_fee_htlc_tx` if the
-               // counterparty doesn't support `option_scid_privacy`. Since `get_initial_channel_type`
-               // checks whether the counterparty supports every feature, this would only happen if the
-               // counterparty is advertising the feature, but rejecting channels proposing the feature for
-               // whatever reason.
-               if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
-                       self.context.channel_type.clear_anchors_zero_fee_htlc_tx();
-                       assert!(self.context.channel_transaction_parameters.opt_non_zero_fee_anchors.is_none());
-                       self.context.channel_transaction_parameters.opt_anchors = None;
-               } else if self.context.channel_type.supports_scid_privacy() {
-                       self.context.channel_type.clear_scid_privacy();
-               } else {
-                       self.context.channel_type = ChannelTypeFeatures::only_static_remote_key();
-               }
-               Ok(self.get_open_channel(chain_hash))
-       }
-
-       // Constructors:
-
        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,
@@ -2396,340 +2420,88 @@ impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
 
        // Message handlers:
 
-       pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures) -> Result<(), ChannelError> {
-               let peer_limits = if let Some(ref limits) = self.context.inbound_handshake_limits_override { limits } else { default_limits };
-
-               // Check sanity of message fields:
+       /// 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<SP: Deref, L: Deref>(
+               &mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
+       ) -> Result<ChannelMonitor<Signer>, ChannelError>
+       where
+               SP::Target: SignerProvider<Signer = Signer>,
+               L::Target: Logger
+       {
                if !self.context.is_outbound() {
-                       return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
-               }
-               if self.context.channel_state != ChannelState::OurInitSent as u32 {
-                       return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
-               }
-               if msg.dust_limit_satoshis > 21000000 * 100000000 {
-                       return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
-               }
-               if msg.channel_reserve_satoshis > self.context.channel_value_satoshis {
-                       return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.context.channel_value_satoshis)));
-               }
-               if msg.dust_limit_satoshis > self.context.holder_selected_channel_reserve_satoshis {
-                       return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, self.context.holder_selected_channel_reserve_satoshis)));
-               }
-               if msg.channel_reserve_satoshis > self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis {
-                       return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
-                               msg.channel_reserve_satoshis, self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis)));
-               }
-               let full_channel_value_msat = (self.context.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
-               if msg.htlc_minimum_msat >= full_channel_value_msat {
-                       return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
-               }
-               let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
-               if msg.to_self_delay > max_delay_acceptable {
-                       return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
+                       return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
                }
-               if msg.max_accepted_htlcs < 1 {
-                       return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
+               if self.context.channel_state & !(ChannelState::MonitorUpdateInProgress as u32) != ChannelState::FundingCreated as u32 {
+                       return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
                }
-               if msg.max_accepted_htlcs > MAX_HTLCS {
-                       return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
+               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
+                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
+                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
                }
 
-               // Now check against optional parameters as set by config...
-               if msg.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
-                       return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
-               }
-               if msg.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
-                       return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
-               }
-               if msg.channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
-                       return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
-               }
-               if msg.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
-                       return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
-               }
-               if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
-               }
-               if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
-                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
-               }
-               if msg.minimum_depth > peer_limits.max_minimum_depth {
-                       return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, msg.minimum_depth)));
-               }
+               let funding_script = self.context.get_funding_redeemscript();
 
-               if let Some(ty) = &msg.channel_type {
-                       if *ty != self.context.channel_type {
-                               return Err(ChannelError::Close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
-                       }
-               } else if their_features.supports_channel_type() {
-                       // Assume they've accepted the channel type as they said they understand it.
-               } else {
-                       let channel_type = ChannelTypeFeatures::from_init(&their_features);
-                       if channel_type != ChannelTypeFeatures::only_static_remote_key() {
-                               return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
+               let counterparty_keys = self.context.build_remote_transaction_keys();
+               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.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();
+
+               log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
+                       log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
+
+               let holder_signer = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+               let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).tx;
+               {
+                       let trusted_tx = initial_commitment_tx.trust();
+                       let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
+                       let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
+                       // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
+                       if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.context.get_counterparty_pubkeys().funding_pubkey) {
+                               return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
                        }
-                       self.context.channel_type = channel_type;
                }
 
-               let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
-                       match &msg.shutdown_scriptpubkey {
-                               &Some(ref script) => {
-                                       // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
-                                       if script.len() == 0 {
-                                               None
-                                       } else {
-                                               if !script::is_bolt2_compliant(&script, their_features) {
-                                                       return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
-                                               }
-                                               Some(script.clone())
-                                       }
-                               },
-                               // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
-                               &None => {
-                                       return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
-                               }
-                       }
-               } else { None };
+               let holder_commitment_tx = HolderCommitmentTransaction::new(
+                       initial_commitment_tx,
+                       msg.signature,
+                       Vec::new(),
+                       &self.context.get_holder_pubkeys().funding_pubkey,
+                       self.context.counterparty_funding_pubkey()
+               );
 
-               self.context.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
-               self.context.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.context.channel_value_satoshis * 1000);
-               self.context.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
-               self.context.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
-               self.context.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
+               self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
+                       .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
 
-               if peer_limits.trust_own_funding_0conf {
-                       self.context.minimum_depth = Some(msg.minimum_depth);
-               } else {
-                       self.context.minimum_depth = Some(cmp::max(1, msg.minimum_depth));
-               }
 
-               let counterparty_pubkeys = ChannelPublicKeys {
-                       funding_pubkey: msg.funding_pubkey,
-                       revocation_basepoint: msg.revocation_basepoint,
-                       payment_point: msg.payment_point,
-                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
-                       htlc_basepoint: msg.htlc_basepoint
-               };
+               let funding_redeemscript = self.context.get_funding_redeemscript();
+               let funding_txo = self.context.get_funding_txo().unwrap();
+               let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
+               let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
+               let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
+               monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+               let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
+                                                         shutdown_script, self.context.get_holder_selected_contest_delay(),
+                                                         &self.context.destination_script, (funding_txo, funding_txo_script),
+                                                         &self.context.channel_transaction_parameters,
+                                                         funding_redeemscript.clone(), self.context.channel_value_satoshis,
+                                                         obscure_factor,
+                                                         holder_commitment_tx, best_block, self.context.counterparty_node_id);
 
-               self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
-                       selected_contest_delay: msg.to_self_delay,
-                       pubkeys: counterparty_pubkeys,
-               });
+               channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
 
-               self.context.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
-               self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
+               assert_eq!(self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32), 0); // We have no had any monitor(s) yet to fail update!
+               self.context.channel_state = ChannelState::FundingSent as u32;
+               self.context.cur_holder_commitment_transaction_number -= 1;
+               self.context.cur_counterparty_commitment_transaction_number -= 1;
 
-               self.context.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
-               self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
+               log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.context.channel_id()));
 
-               Ok(())
-       }
-
-       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.context.get_funding_redeemscript();
-
-               let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
-               let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger).tx;
-               {
-                       let trusted_tx = initial_commitment_tx.trust();
-                       let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
-                       let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
-                       // They sign the holder commitment transaction...
-                       log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
-                               log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.context.counterparty_funding_pubkey().serialize()),
-                               encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
-                               encode::serialize_hex(&funding_script), log_bytes!(self.context.channel_id()));
-                       secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &sig, self.context.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
-               }
-
-               let counterparty_keys = self.context.build_remote_transaction_keys();
-               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.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();
-               log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
-                       log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
-
-               let counterparty_signature = self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
-                               .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
-
-               // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
-               Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
-       }
-
-       pub fn funding_created<SP: Deref, L: Deref>(
-               &mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
-       ) -> Result<(msgs::FundingSigned, ChannelMonitor<Signer>), ChannelError>
-       where
-               SP::Target: SignerProvider<Signer = Signer>,
-               L::Target: Logger
-       {
-               if self.context.is_outbound() {
-                       return Err(ChannelError::Close("Received funding_created for an outbound channel?".to_owned()));
-               }
-               if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
-                       // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
-                       // remember the channel, so it's safe to just send an error_message here and drop the
-                       // channel.
-                       return Err(ChannelError::Close("Received funding_created after we got the channel!".to_owned()));
-               }
-               if self.context.inbound_awaiting_accept {
-                       return Err(ChannelError::Close("FundingCreated message received before the channel was accepted".to_owned()));
-               }
-               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
-                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
-                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
-                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
-               }
-
-               let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
-               self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
-               // This is an externally observable change before we finish all our checks.  In particular
-               // funding_created_signature may fail.
-               self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
-
-               let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
-                       Ok(res) => res,
-                       Err(ChannelError::Close(e)) => {
-                               self.context.channel_transaction_parameters.funding_outpoint = None;
-                               return Err(ChannelError::Close(e));
-                       },
-                       Err(e) => {
-                               // The only error we know how to handle is ChannelError::Close, so we fall over here
-                               // to make sure we don't continue with an inconsistent state.
-                               panic!("unexpected error type from funding_created_signature {:?}", e);
-                       }
-               };
-
-               let holder_commitment_tx = HolderCommitmentTransaction::new(
-                       initial_commitment_tx,
-                       msg.signature,
-                       Vec::new(),
-                       &self.context.get_holder_pubkeys().funding_pubkey,
-                       self.context.counterparty_funding_pubkey()
-               );
-
-               self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
-                       .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
-
-                       // Now that we're past error-generating stuff, update our local state:
-
-               let funding_redeemscript = self.context.get_funding_redeemscript();
-               let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
-               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
-               let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
-               let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
-               monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
-               let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
-                                                         shutdown_script, self.context.get_holder_selected_contest_delay(),
-                                                         &self.context.destination_script, (funding_txo, funding_txo_script.clone()),
-                                                         &self.context.channel_transaction_parameters,
-                                                         funding_redeemscript.clone(), self.context.channel_value_satoshis,
-                                                         obscure_factor,
-                                                         holder_commitment_tx, best_block, self.context.counterparty_node_id);
-
-               channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
-
-               self.context.channel_state = ChannelState::FundingSent as u32;
-               self.context.channel_id = funding_txo.to_channel_id();
-               self.context.cur_counterparty_commitment_transaction_number -= 1;
-               self.context.cur_holder_commitment_transaction_number -= 1;
-
-               log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.context.channel_id()));
-
-               let need_channel_ready = self.check_get_channel_ready(0).is_some();
-               self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
-
-               Ok((msgs::FundingSigned {
-                       channel_id: self.context.channel_id,
-                       signature,
-                       #[cfg(taproot)]
-                       partial_signature_with_nonce: None,
-               }, 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<SP: Deref, L: Deref>(
-               &mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
-       ) -> Result<ChannelMonitor<Signer>, ChannelError>
-       where
-               SP::Target: SignerProvider<Signer = Signer>,
-               L::Target: Logger
-       {
-               if !self.context.is_outbound() {
-                       return Err(ChannelError::Close("Received funding_signed for an inbound channel?".to_owned()));
-               }
-               if self.context.channel_state & !(ChannelState::MonitorUpdateInProgress as u32) != ChannelState::FundingCreated as u32 {
-                       return Err(ChannelError::Close("Received funding_signed in strange state!".to_owned()));
-               }
-               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
-                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
-                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
-                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
-               }
-
-               let funding_script = self.context.get_funding_redeemscript();
-
-               let counterparty_keys = self.context.build_remote_transaction_keys();
-               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.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();
-
-               log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
-                       log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
-
-               let holder_signer = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
-               let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &holder_signer, true, false, logger).tx;
-               {
-                       let trusted_tx = initial_commitment_tx.trust();
-                       let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
-                       let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
-                       // They sign our commitment transaction, allowing us to broadcast the tx if we wish.
-                       if let Err(_) = self.context.secp_ctx.verify_ecdsa(&sighash, &msg.signature, &self.context.get_counterparty_pubkeys().funding_pubkey) {
-                               return Err(ChannelError::Close("Invalid funding_signed signature from peer".to_owned()));
-                       }
-               }
-
-               let holder_commitment_tx = HolderCommitmentTransaction::new(
-                       initial_commitment_tx,
-                       msg.signature,
-                       Vec::new(),
-                       &self.context.get_holder_pubkeys().funding_pubkey,
-                       self.context.counterparty_funding_pubkey()
-               );
-
-               self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new())
-                       .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
-
-
-               let funding_redeemscript = self.context.get_funding_redeemscript();
-               let funding_txo = self.context.get_funding_txo().unwrap();
-               let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
-               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
-               let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
-               let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
-               monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
-               let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
-                                                         shutdown_script, self.context.get_holder_selected_contest_delay(),
-                                                         &self.context.destination_script, (funding_txo, funding_txo_script),
-                                                         &self.context.channel_transaction_parameters,
-                                                         funding_redeemscript.clone(), self.context.channel_value_satoshis,
-                                                         obscure_factor,
-                                                         holder_commitment_tx, best_block, self.context.counterparty_node_id);
-
-               channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_bitcoin_tx.txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
-
-               assert_eq!(self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32), 0); // We have no had any monitor(s) yet to fail update!
-               self.context.channel_state = ChannelState::FundingSent as u32;
-               self.context.cur_holder_commitment_transaction_number -= 1;
-               self.context.cur_counterparty_commitment_transaction_number -= 1;
-
-               log_info!(logger, "Received funding_signed from peer for channel {}", log_bytes!(self.context.channel_id()));
-
-               let need_channel_ready = self.check_get_channel_ready(0).is_some();
-               self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
-               Ok(channel_monitor)
+               let need_channel_ready = self.check_get_channel_ready(0).is_some();
+               self.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
+               Ok(channel_monitor)
        }
 
        /// Handles a channel_ready message from our peer. If we've already sent our channel_ready
@@ -5041,219 +4813,40 @@ impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
        // 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: BlockHash) -> msgs::OpenChannel {
-               if !self.context.is_outbound() {
-                       panic!("Tried to open a channel for an inbound channel?");
-               }
-               if self.context.channel_state != ChannelState::OurInitSent as u32 {
-                       panic!("Cannot generate an open_channel after we've moved forward");
+       /// Gets an UnsignedChannelAnnouncement for this channel. The channel must be publicly
+       /// announceable and available for use (have exchanged ChannelReady messages in both
+       /// directions). Should be used for both broadcasted announcements and in response to an
+       /// AnnouncementSignatures message from the remote peer.
+       ///
+       /// Will only fail if we're not in a state where channel_announcement may be sent (including
+       /// closing).
+       ///
+       /// This will only return ChannelError::Ignore upon failure.
+       fn get_channel_announcement<NS: Deref>(
+               &self, node_signer: &NS, chain_hash: BlockHash, user_config: &UserConfig,
+       ) -> Result<msgs::UnsignedChannelAnnouncement, ChannelError> where NS::Target: NodeSigner {
+               if !self.context.config.announced_channel {
+                       return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
                }
-
-               if self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
-                       panic!("Tried to send an open_channel for a channel that has already advanced");
+               if !self.context.is_usable() {
+                       return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement if the channel is not currently usable".to_owned()));
                }
 
-               let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
-               let keys = self.context.get_holder_pubkeys();
+               let node_id = NodeId::from_pubkey(&node_signer.get_node_id(Recipient::Node)
+                       .map_err(|_| ChannelError::Ignore("Failed to retrieve own public key".to_owned()))?);
+               let counterparty_node_id = NodeId::from_pubkey(&self.context.get_counterparty_node_id());
+               let were_node_one = node_id.as_slice() < counterparty_node_id.as_slice();
 
-               msgs::OpenChannel {
+               let msg = msgs::UnsignedChannelAnnouncement {
+                       features: channelmanager::provided_channel_features(&user_config),
                        chain_hash,
-                       temporary_channel_id: self.context.channel_id,
-                       funding_satoshis: self.context.channel_value_satoshis,
-                       push_msat: self.context.channel_value_satoshis * 1000 - self.context.value_to_self_msat,
-                       dust_limit_satoshis: self.context.holder_dust_limit_satoshis,
-                       max_htlc_value_in_flight_msat: self.context.holder_max_htlc_value_in_flight_msat,
-                       channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
-                       htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
-                       feerate_per_kw: self.context.feerate_per_kw as u32,
-                       to_self_delay: self.context.get_holder_selected_contest_delay(),
-                       max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
-                       funding_pubkey: keys.funding_pubkey,
-                       revocation_basepoint: keys.revocation_basepoint,
-                       payment_point: keys.payment_point,
-                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
-                       htlc_basepoint: keys.htlc_basepoint,
-                       first_per_commitment_point,
-                       channel_flags: if self.context.config.announced_channel {1} else {0},
-                       shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
-                               Some(script) => script.clone().into_inner(),
-                               None => Builder::new().into_script(),
-                       }),
-                       channel_type: Some(self.context.channel_type.clone()),
-               }
-       }
-
-       pub fn inbound_is_awaiting_accept(&self) -> bool {
-               self.context.inbound_awaiting_accept
-       }
-
-       /// Sets this channel to accepting 0conf, must be done before `get_accept_channel`
-       pub fn set_0conf(&mut self) {
-               assert!(self.context.inbound_awaiting_accept);
-               self.context.minimum_depth = Some(0);
-       }
-
-       /// Marks an inbound channel as accepted and generates a [`msgs::AcceptChannel`] message which
-       /// should be sent back to the counterparty node.
-       ///
-       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
-       pub fn accept_inbound_channel(&mut self, user_id: u128) -> msgs::AcceptChannel {
-               if self.context.is_outbound() {
-                       panic!("Tried to send accept_channel for an outbound channel?");
-               }
-               if self.context.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
-                       panic!("Tried to send accept_channel after channel had moved forward");
-               }
-               if self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
-                       panic!("Tried to send an accept_channel for a channel that has already advanced");
-               }
-               if !self.context.inbound_awaiting_accept {
-                       panic!("The inbound channel has already been accepted");
-               }
-
-               self.context.user_id = user_id;
-               self.context.inbound_awaiting_accept = false;
-
-               self.generate_accept_channel_message()
-       }
-
-       /// This function is used to explicitly generate a [`msgs::AcceptChannel`] message for an
-       /// inbound channel. If the intention is to accept an inbound channel, use
-       /// [`Channel::accept_inbound_channel`] instead.
-       ///
-       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
-       fn generate_accept_channel_message(&self) -> msgs::AcceptChannel {
-               let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
-               let keys = self.context.get_holder_pubkeys();
-
-               msgs::AcceptChannel {
-                       temporary_channel_id: self.context.channel_id,
-                       dust_limit_satoshis: self.context.holder_dust_limit_satoshis,
-                       max_htlc_value_in_flight_msat: self.context.holder_max_htlc_value_in_flight_msat,
-                       channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
-                       htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
-                       minimum_depth: self.context.minimum_depth.unwrap(),
-                       to_self_delay: self.context.get_holder_selected_contest_delay(),
-                       max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
-                       funding_pubkey: keys.funding_pubkey,
-                       revocation_basepoint: keys.revocation_basepoint,
-                       payment_point: keys.payment_point,
-                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
-                       htlc_basepoint: keys.htlc_basepoint,
-                       first_per_commitment_point,
-                       shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
-                               Some(script) => script.clone().into_inner(),
-                               None => Builder::new().into_script(),
-                       }),
-                       channel_type: Some(self.context.channel_type.clone()),
-                       #[cfg(taproot)]
-                       next_local_nonce: None,
-               }
-       }
-
-       /// Enables the possibility for tests to extract a [`msgs::AcceptChannel`] message for an
-       /// inbound channel without accepting it.
-       ///
-       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
-       #[cfg(test)]
-       pub fn get_accept_channel_message(&self) -> msgs::AcceptChannel {
-               self.generate_accept_channel_message()
-       }
-
-       /// 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.context.build_remote_transaction_keys();
-               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
-               Ok(self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
-                               .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
-       }
-
-       /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
-       /// a funding_created message for the remote peer.
-       /// Panics if called at some time other than immediately after initial handshake, if called twice,
-       /// or if called on an inbound channel.
-       /// 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<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L) -> Result<msgs::FundingCreated, ChannelError> where L::Target: Logger {
-               if !self.context.is_outbound() {
-                       panic!("Tried to create outbound funding_created message on an inbound channel!");
-               }
-               if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
-                       panic!("Tried to get a funding_created messsage at a time other than immediately after initial handshake completion (or tried to get funding_created twice)");
-               }
-               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
-                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
-                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
-                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
-               }
-
-               self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
-               self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
-
-               let signature = match self.get_outbound_funding_created_signature(logger) {
-                       Ok(res) => res,
-                       Err(e) => {
-                               log_error!(logger, "Got bad signatures: {:?}!", e);
-                               self.context.channel_transaction_parameters.funding_outpoint = None;
-                               return Err(e);
-                       }
-               };
-
-               let temporary_channel_id = self.context.channel_id;
-
-               // Now that we're past error-generating stuff, update our local state:
-
-               self.context.channel_state = ChannelState::FundingCreated as u32;
-               self.context.channel_id = funding_txo.to_channel_id();
-               self.context.funding_transaction = Some(funding_transaction);
-
-               Ok(msgs::FundingCreated {
-                       temporary_channel_id,
-                       funding_txid: funding_txo.txid,
-                       funding_output_index: funding_txo.index,
-                       signature,
-                       #[cfg(taproot)]
-                       partial_signature_with_nonce: None,
-                       #[cfg(taproot)]
-                       next_local_nonce: None,
-               })
-       }
-
-       /// Gets an UnsignedChannelAnnouncement for this channel. The channel must be publicly
-       /// announceable and available for use (have exchanged ChannelReady messages in both
-       /// directions). Should be used for both broadcasted announcements and in response to an
-       /// AnnouncementSignatures message from the remote peer.
-       ///
-       /// Will only fail if we're not in a state where channel_announcement may be sent (including
-       /// closing).
-       ///
-       /// This will only return ChannelError::Ignore upon failure.
-       fn get_channel_announcement<NS: Deref>(
-               &self, node_signer: &NS, chain_hash: BlockHash, user_config: &UserConfig,
-       ) -> Result<msgs::UnsignedChannelAnnouncement, ChannelError> where NS::Target: NodeSigner {
-               if !self.context.config.announced_channel {
-                       return Err(ChannelError::Ignore("Channel is not available for public announcements".to_owned()));
-               }
-               if !self.context.is_usable() {
-                       return Err(ChannelError::Ignore("Cannot get a ChannelAnnouncement if the channel is not currently usable".to_owned()));
-               }
-
-               let node_id = NodeId::from_pubkey(&node_signer.get_node_id(Recipient::Node)
-                       .map_err(|_| ChannelError::Ignore("Failed to retrieve own public key".to_owned()))?);
-               let counterparty_node_id = NodeId::from_pubkey(&self.context.get_counterparty_node_id());
-               let were_node_one = node_id.as_slice() < counterparty_node_id.as_slice();
-
-               let msg = msgs::UnsignedChannelAnnouncement {
-                       features: channelmanager::provided_channel_features(&user_config),
-                       chain_hash,
-                       short_channel_id: self.context.get_short_channel_id().unwrap(),
-                       node_id_1: if were_node_one { node_id } else { counterparty_node_id },
-                       node_id_2: if were_node_one { counterparty_node_id } else { node_id },
-                       bitcoin_key_1: NodeId::from_pubkey(if were_node_one { &self.context.get_holder_pubkeys().funding_pubkey } else { self.context.counterparty_funding_pubkey() }),
-                       bitcoin_key_2: NodeId::from_pubkey(if were_node_one { self.context.counterparty_funding_pubkey() } else { &self.context.get_holder_pubkeys().funding_pubkey }),
-                       excess_data: Vec::new(),
-               };
+                       short_channel_id: self.context.get_short_channel_id().unwrap(),
+                       node_id_1: if were_node_one { node_id } else { counterparty_node_id },
+                       node_id_2: if were_node_one { counterparty_node_id } else { node_id },
+                       bitcoin_key_1: NodeId::from_pubkey(if were_node_one { &self.context.get_holder_pubkeys().funding_pubkey } else { self.context.counterparty_funding_pubkey() }),
+                       bitcoin_key_2: NodeId::from_pubkey(if were_node_one { self.context.counterparty_funding_pubkey() } else { &self.context.get_holder_pubkeys().funding_pubkey }),
+                       excess_data: Vec::new(),
+               };
 
                Ok(msg)
        }
@@ -5823,52 +5416,6 @@ impl<Signer: WriteableEcdsaChannelSigner> Channel<Signer> {
                Ok((shutdown, monitor_update, dropped_outbound_htlcs))
        }
 
-       /// Gets the latest commitment transaction and any dependent transactions for relay (forcing
-       /// shutdown of this channel - no more calls into this Channel may be made afterwards except
-       /// 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, should_broadcast: bool) -> ShutdownResult {
-               // Note that we MUST only generate a monitor update that indicates force-closure - we're
-               // called during initialization prior to the chain_monitor in the encompassing ChannelManager
-               // being fully configured in some cases. Thus, its likely any monitor events we generate will
-               // be delayed in being processed! See the docs for `ChannelManagerReadArgs` for more.
-               assert!(self.context.channel_state != ChannelState::ShutdownComplete as u32);
-
-               // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
-               // return them to fail the payment.
-               let mut dropped_outbound_htlcs = Vec::with_capacity(self.context.holding_cell_htlc_updates.len());
-               let counterparty_node_id = self.context.get_counterparty_node_id();
-               for htlc_update in self.context.holding_cell_htlc_updates.drain(..) {
-                       match htlc_update {
-                               HTLCUpdateAwaitingACK::AddHTLC { source, payment_hash, .. } => {
-                                       dropped_outbound_htlcs.push((source, payment_hash, counterparty_node_id, self.context.channel_id));
-                               },
-                               _ => {}
-                       }
-               }
-               let monitor_update = if let Some(funding_txo) = self.context.get_funding_txo() {
-                       // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
-                       // returning a channel monitor update here would imply a channel monitor update before
-                       // we even registered the channel monitor to begin with, which is invalid.
-                       // Thus, if we aren't actually at a point where we could conceivably broadcast the
-                       // 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.context.channel_state & (ChannelState::FundingSent as u32 | ChannelState::ChannelReady as u32 | ChannelState::ShutdownComplete as u32) != 0 {
-                               self.context.latest_monitor_update_id = CLOSED_CHANNEL_UPDATE_ID;
-                               Some((self.context.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
-                                       update_id: self.context.latest_monitor_update_id,
-                                       updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
-                               }))
-                       } else { None }
-               } else { None };
-
-               self.context.channel_state = ChannelState::ShutdownComplete as u32;
-               self.context.update_time_counter += 1;
-               (monitor_update, dropped_outbound_htlcs)
-       }
-
        pub fn inflight_htlc_sources(&self) -> impl Iterator<Item=(&HTLCSource, &PaymentHash)> {
                self.context.holding_cell_htlc_updates.iter()
                        .flat_map(|htlc_update| {
@@ -5888,37 +5435,11 @@ pub(super) struct OutboundV1Channel<Signer: ChannelSigner> {
 }
 
 impl<Signer: WriteableEcdsaChannelSigner> OutboundV1Channel<Signer> {
-       fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
-               // The default channel type (ie the first one we try) depends on whether the channel is
-               // public - if it is, we just go with `only_static_remotekey` as it's the only option
-               // available. If it's private, we first try `scid_privacy` as it provides better privacy
-               // with no other changes, and fall back to `only_static_remotekey`.
-               let mut ret = ChannelTypeFeatures::only_static_remote_key();
-               if !config.channel_handshake_config.announced_channel &&
-                       config.channel_handshake_config.negotiate_scid_privacy &&
-                       their_features.supports_scid_privacy() {
-                       ret.set_scid_privacy_required();
-               }
-
-               // Optionally, if the user would like to negotiate the `anchors_zero_fee_htlc_tx` option, we
-               // set it now. If they don't understand it, we'll fall back to our default of
-               // `only_static_remotekey`.
-               #[cfg(anchors)]
-               { // Attributes are not allowed on if expressions on our current MSRV of 1.41.
-                       if config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx &&
-                               their_features.supports_anchors_zero_fee_htlc_tx() {
-                               ret.set_anchors_zero_fee_htlc_tx_required();
-                       }
-               }
-
-               ret
-       }
-
-       pub fn new_outbound<ES: Deref, SP: Deref, F: Deref>(
+       pub fn new<ES: Deref, SP: Deref, F: Deref>(
                fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP, counterparty_node_id: PublicKey, their_features: &InitFeatures,
                channel_value_satoshis: u64, push_msat: u64, user_id: u128, config: &UserConfig, current_chain_height: u32,
                outbound_scid_alias: u64
-       ) -> Result<Channel<Signer>, APIError>
+       ) -> Result<OutboundV1Channel<Signer>, APIError>
        where ES::Target: EntropySource,
              SP::Target: SignerProvider<Signer = Signer>,
              F::Target: FeeEstimator,
@@ -5982,7 +5503,7 @@ impl<Signer: WriteableEcdsaChannelSigner> OutboundV1Channel<Signer> {
 
                let temporary_channel_id = entropy_source.get_secure_random_bytes();
 
-               Ok(Channel {
+               Ok(Self {
                        context: ChannelContext {
                                user_id,
 
@@ -6092,24 +5613,317 @@ impl<Signer: WriteableEcdsaChannelSigner> OutboundV1Channel<Signer> {
                                #[cfg(any(test, fuzzing))]
                                next_remote_commitment_tx_fee_info_cached: Mutex::new(None),
 
-                               workaround_lnd_bug_4006: None,
-                               sent_message_awaiting_response: None,
+                               workaround_lnd_bug_4006: None,
+                               sent_message_awaiting_response: None,
+
+                               latest_inbound_scid_alias: None,
+                               outbound_scid_alias,
+
+                               channel_pending_event_emitted: false,
+                               channel_ready_event_emitted: false,
+
+                               #[cfg(any(test, fuzzing))]
+                               historical_inbound_htlc_fulfills: HashSet::new(),
+
+                               channel_type,
+                               channel_keys_id,
+
+                               pending_monitor_updates: Vec::new(),
+                       }
+               })
+       }
+
+       /// 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.context.build_remote_transaction_keys();
+               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
+               Ok(self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
+                               .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0)
+       }
+
+       /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
+       /// a funding_created message for the remote peer.
+       /// Panics if called at some time other than immediately after initial handshake, if called twice,
+       /// or if called on an inbound channel.
+       /// 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<L: Deref>(mut self, funding_transaction: Transaction, funding_txo: OutPoint, logger: &L)
+       -> Result<(Channel<Signer>, msgs::FundingCreated), (Self, ChannelError)> where L::Target: Logger {
+               if !self.context.is_outbound() {
+                       panic!("Tried to create outbound funding_created message on an inbound channel!");
+               }
+               if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
+                       panic!("Tried to get a funding_created messsage at a time other than immediately after initial handshake completion (or tried to get funding_created twice)");
+               }
+               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
+                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
+                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+               }
+
+               self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
+               self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+
+               let signature = match self.get_outbound_funding_created_signature(logger) {
+                       Ok(res) => res,
+                       Err(e) => {
+                               log_error!(logger, "Got bad signatures: {:?}!", e);
+                               self.context.channel_transaction_parameters.funding_outpoint = None;
+                               return Err((self, e));
+                       }
+               };
+
+               let temporary_channel_id = self.context.channel_id;
+
+               // Now that we're past error-generating stuff, update our local state:
+
+               self.context.channel_state = ChannelState::FundingCreated as u32;
+               self.context.channel_id = funding_txo.to_channel_id();
+               self.context.funding_transaction = Some(funding_transaction);
+
+               let channel = Channel {
+                       context: self.context,
+               };
+
+               Ok((channel, msgs::FundingCreated {
+                       temporary_channel_id,
+                       funding_txid: funding_txo.txid,
+                       funding_output_index: funding_txo.index,
+                       signature,
+                       #[cfg(taproot)]
+                       partial_signature_with_nonce: None,
+                       #[cfg(taproot)]
+                       next_local_nonce: None,
+               }))
+       }
+
+       fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
+               // The default channel type (ie the first one we try) depends on whether the channel is
+               // public - if it is, we just go with `only_static_remotekey` as it's the only option
+               // available. If it's private, we first try `scid_privacy` as it provides better privacy
+               // with no other changes, and fall back to `only_static_remotekey`.
+               let mut ret = ChannelTypeFeatures::only_static_remote_key();
+               if !config.channel_handshake_config.announced_channel &&
+                       config.channel_handshake_config.negotiate_scid_privacy &&
+                       their_features.supports_scid_privacy() {
+                       ret.set_scid_privacy_required();
+               }
+
+               // Optionally, if the user would like to negotiate the `anchors_zero_fee_htlc_tx` option, we
+               // set it now. If they don't understand it, we'll fall back to our default of
+               // `only_static_remotekey`.
+               #[cfg(anchors)]
+               { // Attributes are not allowed on if expressions on our current MSRV of 1.41.
+                       if config.channel_handshake_config.negotiate_anchors_zero_fee_htlc_tx &&
+                               their_features.supports_anchors_zero_fee_htlc_tx() {
+                               ret.set_anchors_zero_fee_htlc_tx_required();
+                       }
+               }
+
+               ret
+       }
+
+       /// If we receive an error message, it may only be a rejection of the channel type we tried,
+       /// not of our ability to open any channel at all. Thus, on error, we should first call this
+       /// and see if we get a new `OpenChannel` message, otherwise the channel is failed.
+       pub(crate) fn maybe_handle_error_without_close(&mut self, chain_hash: BlockHash) -> Result<msgs::OpenChannel, ()> {
+               if !self.context.is_outbound() || self.context.channel_state != ChannelState::OurInitSent as u32 { return Err(()); }
+               if self.context.channel_type == ChannelTypeFeatures::only_static_remote_key() {
+                       // We've exhausted our options
+                       return Err(());
+               }
+               // We support opening a few different types of channels. Try removing our additional
+               // features one by one until we've either arrived at our default or the counterparty has
+               // accepted one.
+               //
+               // Due to the order below, we may not negotiate `option_anchors_zero_fee_htlc_tx` if the
+               // counterparty doesn't support `option_scid_privacy`. Since `get_initial_channel_type`
+               // checks whether the counterparty supports every feature, this would only happen if the
+               // counterparty is advertising the feature, but rejecting channels proposing the feature for
+               // whatever reason.
+               if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
+                       self.context.channel_type.clear_anchors_zero_fee_htlc_tx();
+                       assert!(self.context.channel_transaction_parameters.opt_non_zero_fee_anchors.is_none());
+                       self.context.channel_transaction_parameters.opt_anchors = None;
+               } else if self.context.channel_type.supports_scid_privacy() {
+                       self.context.channel_type.clear_scid_privacy();
+               } else {
+                       self.context.channel_type = ChannelTypeFeatures::only_static_remote_key();
+               }
+               Ok(self.get_open_channel(chain_hash))
+       }
+
+       pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
+               if !self.context.is_outbound() {
+                       panic!("Tried to open a channel for an inbound channel?");
+               }
+               if self.context.channel_state != ChannelState::OurInitSent as u32 {
+                       panic!("Cannot generate an open_channel after we've moved forward");
+               }
+
+               if self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+                       panic!("Tried to send an open_channel for a channel that has already advanced");
+               }
+
+               let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
+               let keys = self.context.get_holder_pubkeys();
+
+               msgs::OpenChannel {
+                       chain_hash,
+                       temporary_channel_id: self.context.channel_id,
+                       funding_satoshis: self.context.channel_value_satoshis,
+                       push_msat: self.context.channel_value_satoshis * 1000 - self.context.value_to_self_msat,
+                       dust_limit_satoshis: self.context.holder_dust_limit_satoshis,
+                       max_htlc_value_in_flight_msat: self.context.holder_max_htlc_value_in_flight_msat,
+                       channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
+                       htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
+                       feerate_per_kw: self.context.feerate_per_kw as u32,
+                       to_self_delay: self.context.get_holder_selected_contest_delay(),
+                       max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
+                       funding_pubkey: keys.funding_pubkey,
+                       revocation_basepoint: keys.revocation_basepoint,
+                       payment_point: keys.payment_point,
+                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
+                       htlc_basepoint: keys.htlc_basepoint,
+                       first_per_commitment_point,
+                       channel_flags: if self.context.config.announced_channel {1} else {0},
+                       shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
+                               Some(script) => script.clone().into_inner(),
+                               None => Builder::new().into_script(),
+                       }),
+                       channel_type: Some(self.context.channel_type.clone()),
+               }
+       }
+
+       // Message handlers
+       pub fn accept_channel(&mut self, msg: &msgs::AcceptChannel, default_limits: &ChannelHandshakeLimits, their_features: &InitFeatures) -> Result<(), ChannelError> {
+               let peer_limits = if let Some(ref limits) = self.context.inbound_handshake_limits_override { limits } else { default_limits };
+
+               // Check sanity of message fields:
+               if !self.context.is_outbound() {
+                       return Err(ChannelError::Close("Got an accept_channel message from an inbound peer".to_owned()));
+               }
+               if self.context.channel_state != ChannelState::OurInitSent as u32 {
+                       return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
+               }
+               if msg.dust_limit_satoshis > 21000000 * 100000000 {
+                       return Err(ChannelError::Close(format!("Peer never wants payout outputs? dust_limit_satoshis was {}", msg.dust_limit_satoshis)));
+               }
+               if msg.channel_reserve_satoshis > self.context.channel_value_satoshis {
+                       return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than ({})", msg.channel_reserve_satoshis, self.context.channel_value_satoshis)));
+               }
+               if msg.dust_limit_satoshis > self.context.holder_selected_channel_reserve_satoshis {
+                       return Err(ChannelError::Close(format!("Dust limit ({}) is bigger than our channel reserve ({})", msg.dust_limit_satoshis, self.context.holder_selected_channel_reserve_satoshis)));
+               }
+               if msg.channel_reserve_satoshis > self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis {
+                       return Err(ChannelError::Close(format!("Bogus channel_reserve_satoshis ({}). Must not be greater than channel value minus our reserve ({})",
+                               msg.channel_reserve_satoshis, self.context.channel_value_satoshis - self.context.holder_selected_channel_reserve_satoshis)));
+               }
+               let full_channel_value_msat = (self.context.channel_value_satoshis - msg.channel_reserve_satoshis) * 1000;
+               if msg.htlc_minimum_msat >= full_channel_value_msat {
+                       return Err(ChannelError::Close(format!("Minimum htlc value ({}) is full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
+               }
+               let max_delay_acceptable = u16::min(peer_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
+               if msg.to_self_delay > max_delay_acceptable {
+                       return Err(ChannelError::Close(format!("They wanted our payments to be delayed by a needlessly long period. Upper limit: {}. Actual: {}", max_delay_acceptable, msg.to_self_delay)));
+               }
+               if msg.max_accepted_htlcs < 1 {
+                       return Err(ChannelError::Close("0 max_accepted_htlcs makes for a useless channel".to_owned()));
+               }
+               if msg.max_accepted_htlcs > MAX_HTLCS {
+                       return Err(ChannelError::Close(format!("max_accepted_htlcs was {}. It must not be larger than {}", msg.max_accepted_htlcs, MAX_HTLCS)));
+               }
+
+               // Now check against optional parameters as set by config...
+               if msg.htlc_minimum_msat > peer_limits.max_htlc_minimum_msat {
+                       return Err(ChannelError::Close(format!("htlc_minimum_msat ({}) is higher than the user specified limit ({})", msg.htlc_minimum_msat, peer_limits.max_htlc_minimum_msat)));
+               }
+               if msg.max_htlc_value_in_flight_msat < peer_limits.min_max_htlc_value_in_flight_msat {
+                       return Err(ChannelError::Close(format!("max_htlc_value_in_flight_msat ({}) is less than the user specified limit ({})", msg.max_htlc_value_in_flight_msat, peer_limits.min_max_htlc_value_in_flight_msat)));
+               }
+               if msg.channel_reserve_satoshis > peer_limits.max_channel_reserve_satoshis {
+                       return Err(ChannelError::Close(format!("channel_reserve_satoshis ({}) is higher than the user specified limit ({})", msg.channel_reserve_satoshis, peer_limits.max_channel_reserve_satoshis)));
+               }
+               if msg.max_accepted_htlcs < peer_limits.min_max_accepted_htlcs {
+                       return Err(ChannelError::Close(format!("max_accepted_htlcs ({}) is less than the user specified limit ({})", msg.max_accepted_htlcs, peer_limits.min_max_accepted_htlcs)));
+               }
+               if msg.dust_limit_satoshis < MIN_CHAN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is less than the implementation limit ({})", msg.dust_limit_satoshis, MIN_CHAN_DUST_LIMIT_SATOSHIS)));
+               }
+               if msg.dust_limit_satoshis > MAX_CHAN_DUST_LIMIT_SATOSHIS {
+                       return Err(ChannelError::Close(format!("dust_limit_satoshis ({}) is greater than the implementation limit ({})", msg.dust_limit_satoshis, MAX_CHAN_DUST_LIMIT_SATOSHIS)));
+               }
+               if msg.minimum_depth > peer_limits.max_minimum_depth {
+                       return Err(ChannelError::Close(format!("We consider the minimum depth to be unreasonably large. Expected minimum: ({}). Actual: ({})", peer_limits.max_minimum_depth, msg.minimum_depth)));
+               }
+
+               if let Some(ty) = &msg.channel_type {
+                       if *ty != self.context.channel_type {
+                               return Err(ChannelError::Close("Channel Type in accept_channel didn't match the one sent in open_channel.".to_owned()));
+                       }
+               } else if their_features.supports_channel_type() {
+                       // Assume they've accepted the channel type as they said they understand it.
+               } else {
+                       let channel_type = ChannelTypeFeatures::from_init(&their_features);
+                       if channel_type != ChannelTypeFeatures::only_static_remote_key() {
+                               return Err(ChannelError::Close("Only static_remote_key is supported for non-negotiated channel types".to_owned()));
+                       }
+                       self.context.channel_type = channel_type;
+               }
+
+               let counterparty_shutdown_scriptpubkey = if their_features.supports_upfront_shutdown_script() {
+                       match &msg.shutdown_scriptpubkey {
+                               &Some(ref script) => {
+                                       // Peer is signaling upfront_shutdown and has opt-out with a 0-length script. We don't enforce anything
+                                       if script.len() == 0 {
+                                               None
+                                       } else {
+                                               if !script::is_bolt2_compliant(&script, their_features) {
+                                                       return Err(ChannelError::Close(format!("Peer is signaling upfront_shutdown but has provided an unacceptable scriptpubkey format: {}", script)));
+                                               }
+                                               Some(script.clone())
+                                       }
+                               },
+                               // Peer is signaling upfront shutdown but don't opt-out with correct mechanism (a.k.a 0-length script). Peer looks buggy, we fail the channel
+                               &None => {
+                                       return Err(ChannelError::Close("Peer is signaling upfront_shutdown but we don't get any script. Use 0-length script to opt-out".to_owned()));
+                               }
+                       }
+               } else { None };
+
+               self.context.counterparty_dust_limit_satoshis = msg.dust_limit_satoshis;
+               self.context.counterparty_max_htlc_value_in_flight_msat = cmp::min(msg.max_htlc_value_in_flight_msat, self.context.channel_value_satoshis * 1000);
+               self.context.counterparty_selected_channel_reserve_satoshis = Some(msg.channel_reserve_satoshis);
+               self.context.counterparty_htlc_minimum_msat = msg.htlc_minimum_msat;
+               self.context.counterparty_max_accepted_htlcs = msg.max_accepted_htlcs;
+
+               if peer_limits.trust_own_funding_0conf {
+                       self.context.minimum_depth = Some(msg.minimum_depth);
+               } else {
+                       self.context.minimum_depth = Some(cmp::max(1, msg.minimum_depth));
+               }
 
-                               latest_inbound_scid_alias: None,
-                               outbound_scid_alias,
+               let counterparty_pubkeys = ChannelPublicKeys {
+                       funding_pubkey: msg.funding_pubkey,
+                       revocation_basepoint: msg.revocation_basepoint,
+                       payment_point: msg.payment_point,
+                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
+                       htlc_basepoint: msg.htlc_basepoint
+               };
 
-                               channel_pending_event_emitted: false,
-                               channel_ready_event_emitted: false,
+               self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
+                       selected_contest_delay: msg.to_self_delay,
+                       pubkeys: counterparty_pubkeys,
+               });
 
-                               #[cfg(any(test, fuzzing))]
-                               historical_inbound_htlc_fulfills: HashSet::new(),
+               self.context.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
+               self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
 
-                               channel_type,
-                               channel_keys_id,
+               self.context.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
+               self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
 
-                               pending_monitor_updates: Vec::new(),
-                       }
-               })
+               Ok(())
        }
 }
 
@@ -6121,12 +5935,12 @@ pub(super) struct InboundV1Channel<Signer: ChannelSigner> {
 impl<Signer: WriteableEcdsaChannelSigner> InboundV1Channel<Signer> {
        /// 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<ES: Deref, SP: Deref, F: Deref, L: Deref>(
+       pub fn new<ES: Deref, SP: Deref, F: Deref, L: Deref>(
                fee_estimator: &LowerBoundedFeeEstimator<F>, entropy_source: &ES, signer_provider: &SP,
                counterparty_node_id: PublicKey, our_supported_features: &ChannelTypeFeatures,
                their_features: &InitFeatures, msg: &msgs::OpenChannel, user_id: u128, config: &UserConfig,
                current_chain_height: u32, logger: &L, outbound_scid_alias: u64
-       ) -> Result<Channel<Signer>, ChannelError>
+       ) -> Result<InboundV1Channel<Signer>, ChannelError>
                where ES::Target: EntropySource,
                          SP::Target: SignerProvider<Signer = Signer>,
                          F::Target: FeeEstimator,
@@ -6316,7 +6130,7 @@ impl<Signer: WriteableEcdsaChannelSigner> InboundV1Channel<Signer> {
                let mut secp_ctx = Secp256k1::new();
                secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
 
-               let chan = Channel {
+               let chan = Self {
                        context: ChannelContext {
                                user_id,
 
@@ -6450,6 +6264,213 @@ impl<Signer: WriteableEcdsaChannelSigner> InboundV1Channel<Signer> {
 
                Ok(chan)
        }
+
+       pub fn is_awaiting_accept(&self) -> bool {
+               self.context.inbound_awaiting_accept
+       }
+
+       /// Sets this channel to accepting 0conf, must be done before `get_accept_channel`
+       pub fn set_0conf(&mut self) {
+               assert!(self.context.inbound_awaiting_accept);
+               self.context.minimum_depth = Some(0);
+       }
+
+       /// Marks an inbound channel as accepted and generates a [`msgs::AcceptChannel`] message which
+       /// should be sent back to the counterparty node.
+       ///
+       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
+       pub fn accept_inbound_channel(&mut self, user_id: u128) -> msgs::AcceptChannel {
+               if self.context.is_outbound() {
+                       panic!("Tried to send accept_channel for an outbound channel?");
+               }
+               if self.context.channel_state != (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32) {
+                       panic!("Tried to send accept_channel after channel had moved forward");
+               }
+               if self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+                       panic!("Tried to send an accept_channel for a channel that has already advanced");
+               }
+               if !self.context.inbound_awaiting_accept {
+                       panic!("The inbound channel has already been accepted");
+               }
+
+               self.context.user_id = user_id;
+               self.context.inbound_awaiting_accept = false;
+
+               self.generate_accept_channel_message()
+       }
+
+       /// This function is used to explicitly generate a [`msgs::AcceptChannel`] message for an
+       /// inbound channel. If the intention is to accept an inbound channel, use
+       /// [`InboundV1Channel::accept_inbound_channel`] instead.
+       ///
+       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
+       fn generate_accept_channel_message(&self) -> msgs::AcceptChannel {
+               let first_per_commitment_point = self.context.holder_signer.get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
+               let keys = self.context.get_holder_pubkeys();
+
+               msgs::AcceptChannel {
+                       temporary_channel_id: self.context.channel_id,
+                       dust_limit_satoshis: self.context.holder_dust_limit_satoshis,
+                       max_htlc_value_in_flight_msat: self.context.holder_max_htlc_value_in_flight_msat,
+                       channel_reserve_satoshis: self.context.holder_selected_channel_reserve_satoshis,
+                       htlc_minimum_msat: self.context.holder_htlc_minimum_msat,
+                       minimum_depth: self.context.minimum_depth.unwrap(),
+                       to_self_delay: self.context.get_holder_selected_contest_delay(),
+                       max_accepted_htlcs: self.context.holder_max_accepted_htlcs,
+                       funding_pubkey: keys.funding_pubkey,
+                       revocation_basepoint: keys.revocation_basepoint,
+                       payment_point: keys.payment_point,
+                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
+                       htlc_basepoint: keys.htlc_basepoint,
+                       first_per_commitment_point,
+                       shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
+                               Some(script) => script.clone().into_inner(),
+                               None => Builder::new().into_script(),
+                       }),
+                       channel_type: Some(self.context.channel_type.clone()),
+                       #[cfg(taproot)]
+                       next_local_nonce: None,
+               }
+       }
+
+       /// Enables the possibility for tests to extract a [`msgs::AcceptChannel`] message for an
+       /// inbound channel without accepting it.
+       ///
+       /// [`msgs::AcceptChannel`]: crate::ln::msgs::AcceptChannel
+       #[cfg(test)]
+       pub fn get_accept_channel_message(&self) -> msgs::AcceptChannel {
+               self.generate_accept_channel_message()
+       }
+
+       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.context.get_funding_redeemscript();
+
+               let keys = self.context.build_holder_transaction_keys(self.context.cur_holder_commitment_transaction_number);
+               let initial_commitment_tx = self.context.build_commitment_transaction(self.context.cur_holder_commitment_transaction_number, &keys, true, false, logger).tx;
+               {
+                       let trusted_tx = initial_commitment_tx.trust();
+                       let initial_commitment_bitcoin_tx = trusted_tx.built_transaction();
+                       let sighash = initial_commitment_bitcoin_tx.get_sighash_all(&funding_script, self.context.channel_value_satoshis);
+                       // They sign the holder commitment transaction...
+                       log_trace!(logger, "Checking funding_created tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} for channel {}.",
+                               log_bytes!(sig.serialize_compact()[..]), log_bytes!(self.context.counterparty_funding_pubkey().serialize()),
+                               encode::serialize_hex(&initial_commitment_bitcoin_tx.transaction), log_bytes!(sighash[..]),
+                               encode::serialize_hex(&funding_script), log_bytes!(self.context.channel_id()));
+                       secp_check!(self.context.secp_ctx.verify_ecdsa(&sighash, &sig, self.context.counterparty_funding_pubkey()), "Invalid funding_created signature from peer".to_owned());
+               }
+
+               let counterparty_keys = self.context.build_remote_transaction_keys();
+               let counterparty_initial_commitment_tx = self.context.build_commitment_transaction(self.context.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();
+               log_trace!(logger, "Initial counterparty tx for channel {} is: txid {} tx {}",
+                       log_bytes!(self.context.channel_id()), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
+
+               let counterparty_signature = self.context.holder_signer.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.context.secp_ctx)
+                               .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?.0;
+
+               // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
+               Ok((counterparty_initial_bitcoin_tx.txid, initial_commitment_tx, counterparty_signature))
+       }
+
+       pub fn funding_created<SP: Deref, L: Deref>(
+               mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
+       ) -> Result<(Channel<Signer>, msgs::FundingSigned, ChannelMonitor<Signer>), (Self, ChannelError)>
+       where
+               SP::Target: SignerProvider<Signer = Signer>,
+               L::Target: Logger
+       {
+               if self.context.is_outbound() {
+                       return Err((self, ChannelError::Close("Received funding_created for an outbound channel?".to_owned())));
+               }
+               if self.context.channel_state != (ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32) {
+                       // BOLT 2 says that if we disconnect before we send funding_signed we SHOULD NOT
+                       // remember the channel, so it's safe to just send an error_message here and drop the
+                       // channel.
+                       return Err((self, ChannelError::Close("Received funding_created after we got the channel!".to_owned())));
+               }
+               if self.context.inbound_awaiting_accept {
+                       return Err((self, ChannelError::Close("FundingCreated message received before the channel was accepted".to_owned())));
+               }
+               if self.context.commitment_secrets.get_min_seen_secret() != (1 << 48) ||
+                               self.context.cur_counterparty_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER ||
+                               self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
+                       panic!("Should not have advanced channel commitment tx numbers prior to funding_created");
+               }
+
+               let funding_txo = OutPoint { txid: msg.funding_txid, index: msg.funding_output_index };
+               self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
+               // This is an externally observable change before we finish all our checks.  In particular
+               // funding_created_signature may fail.
+               self.context.holder_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+
+               let (counterparty_initial_commitment_txid, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
+                       Ok(res) => res,
+                       Err(ChannelError::Close(e)) => {
+                               self.context.channel_transaction_parameters.funding_outpoint = None;
+                               return Err((self, ChannelError::Close(e)));
+                       },
+                       Err(e) => {
+                               // The only error we know how to handle is ChannelError::Close, so we fall over here
+                               // to make sure we don't continue with an inconsistent state.
+                               panic!("unexpected error type from funding_created_signature {:?}", e);
+                       }
+               };
+
+               let holder_commitment_tx = HolderCommitmentTransaction::new(
+                       initial_commitment_tx,
+                       msg.signature,
+                       Vec::new(),
+                       &self.context.get_holder_pubkeys().funding_pubkey,
+                       self.context.counterparty_funding_pubkey()
+               );
+
+               if let Err(_) = self.context.holder_signer.validate_holder_commitment(&holder_commitment_tx, Vec::new()) {
+                       return Err((self, ChannelError::Close("Failed to validate our commitment".to_owned())));
+               }
+
+               // Now that we're past error-generating stuff, update our local state:
+
+               let funding_redeemscript = self.context.get_funding_redeemscript();
+               let funding_txo_script = funding_redeemscript.to_v0_p2wsh();
+               let obscure_factor = get_commitment_transaction_number_obscure_factor(&self.context.get_holder_pubkeys().payment_point, &self.context.get_counterparty_pubkeys().payment_point, self.context.is_outbound());
+               let shutdown_script = self.context.shutdown_scriptpubkey.clone().map(|script| script.into_inner());
+               let mut monitor_signer = signer_provider.derive_channel_signer(self.context.channel_value_satoshis, self.context.channel_keys_id);
+               monitor_signer.provide_channel_parameters(&self.context.channel_transaction_parameters);
+               let channel_monitor = ChannelMonitor::new(self.context.secp_ctx.clone(), monitor_signer,
+                                                         shutdown_script, self.context.get_holder_selected_contest_delay(),
+                                                         &self.context.destination_script, (funding_txo, funding_txo_script.clone()),
+                                                         &self.context.channel_transaction_parameters,
+                                                         funding_redeemscript.clone(), self.context.channel_value_satoshis,
+                                                         obscure_factor,
+                                                         holder_commitment_tx, best_block, self.context.counterparty_node_id);
+
+               channel_monitor.provide_latest_counterparty_commitment_tx(counterparty_initial_commitment_txid, Vec::new(), self.context.cur_counterparty_commitment_transaction_number, self.context.counterparty_cur_commitment_point.unwrap(), logger);
+
+               self.context.channel_state = ChannelState::FundingSent as u32;
+               self.context.channel_id = funding_txo.to_channel_id();
+               self.context.cur_counterparty_commitment_transaction_number -= 1;
+               self.context.cur_holder_commitment_transaction_number -= 1;
+
+               log_info!(logger, "Generated funding_signed for peer for channel {}", log_bytes!(self.context.channel_id()));
+
+               // Promote the channel to a full-fledged one now that we have updated the state and have a
+               // `ChannelMonitor`.
+               let mut channel = Channel {
+                       context: self.context,
+               };
+               let channel_id = channel.context.channel_id.clone();
+               let need_channel_ready = channel.check_get_channel_ready(0).is_some();
+               channel.monitor_updating_paused(false, false, need_channel_ready, Vec::new(), Vec::new(), Vec::new());
+
+               Ok((channel, msgs::FundingSigned {
+                       channel_id,
+                       signature,
+                       #[cfg(taproot)]
+                       partial_signature_with_nonce: None,
+               }, channel_monitor))
+       }
 }
 
 const SERIALIZATION_VERSION: u8 = 3;
@@ -7404,7 +7425,7 @@ mod tests {
                let secp_ctx = Secp256k1::new();
                let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               match OutboundV1Channel::<EnforcingSigner>::new_outbound(&LowerBoundedFeeEstimator::new(&TestFeeEstimator { fee_est: 253 }), &&keys_provider, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0, 42) {
+               match OutboundV1Channel::<EnforcingSigner>::new(&LowerBoundedFeeEstimator::new(&TestFeeEstimator { fee_est: 253 }), &&keys_provider, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0, 42) {
                        Err(APIError::IncompatibleShutdownScript { script }) => {
                                assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
                        },
@@ -7427,7 +7448,7 @@ mod tests {
 
                let node_a_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let node_a_chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&bounded_fee_estimator, &&keys_provider, &&keys_provider, node_a_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+               let node_a_chan = OutboundV1Channel::<EnforcingSigner>::new(&bounded_fee_estimator, &&keys_provider, &&keys_provider, node_a_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
 
                // Now change the fee so we can check that the fee in the open_channel message is the
                // same as the old fee.
@@ -7446,6 +7467,7 @@ mod tests {
                let network = Network::Testnet;
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
                let logger = test_utils::TestLogger::new();
+               let best_block = BestBlock::from_network(network);
 
                // Go through the flow of opening a channel between two nodes, making sure
                // they have different dust limits.
@@ -7453,13 +7475,13 @@ mod tests {
                // Create Node A's channel pointing to Node B's pubkey
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
 
                // Create Node B's channel by receiving Node A's open_channel message
                // Make sure A's dust limit is as we expect.
                let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
-               let mut node_b_chan = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42).unwrap();
+               let mut node_b_chan = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42).unwrap();
 
                // Node B --> Node A: accept channel, explicitly setting B's dust limit.
                let mut accept_channel_msg = node_b_chan.accept_inbound_channel(0);
@@ -7467,6 +7489,18 @@ mod tests {
                node_a_chan.accept_channel(&accept_channel_msg, &config.channel_handshake_limits, &channelmanager::provided_init_features(&config)).unwrap();
                node_a_chan.context.holder_dust_limit_satoshis = 1560;
 
+               // Node A --> Node B: funding created
+               let output_script = node_a_chan.context.get_funding_redeemscript();
+               let tx = Transaction { version: 1, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: vec![TxOut {
+                       value: 10000000, script_pubkey: output_script.clone(),
+               }]};
+               let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
+               let (mut node_a_chan, funding_created_msg) = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).map_err(|_| ()).unwrap();
+               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).map_err(|_| ()).unwrap();
+
+               // Node B --> Node A: funding signed
+               let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&keys_provider, &&logger).unwrap();
+
                // Put some inbound and outbound HTLCs in A's channel.
                let htlc_amount_msat = 11_092_000; // put an amount below A's effective dust limit but above B's.
                node_a_chan.context.pending_inbound_htlcs.push(InboundHTLCOutput {
@@ -7521,7 +7555,7 @@ mod tests {
 
                let node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let mut chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&fee_est, &&keys_provider, &&keys_provider, node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+               let mut chan = OutboundV1Channel::<EnforcingSigner>::new(&fee_est, &&keys_provider, &&keys_provider, node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
 
                let commitment_tx_fee_0_htlcs = commit_tx_fee_msat(chan.context.feerate_per_kw, 0, chan.context.opt_anchors());
                let commitment_tx_fee_1_htlc = commit_tx_fee_msat(chan.context.feerate_per_kw, 1, chan.context.opt_anchors());
@@ -7570,12 +7604,12 @@ mod tests {
                // Create Node A's channel pointing to Node B's pubkey
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
 
                // Create Node B's channel by receiving Node A's open_channel message
                let open_channel_msg = node_a_chan.get_open_channel(chain_hash);
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
-               let mut node_b_chan = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42).unwrap();
+               let mut node_b_chan = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42).unwrap();
 
                // Node B --> Node A: accept channel
                let accept_channel_msg = node_b_chan.accept_inbound_channel(0);
@@ -7587,11 +7621,11 @@ mod tests {
                        value: 10000000, script_pubkey: output_script.clone(),
                }]};
                let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
-               let funding_created_msg = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).unwrap();
-               let (funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).unwrap();
+               let (mut node_a_chan, funding_created_msg) = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).map_err(|_| ()).unwrap();
+               let (mut node_b_chan, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).map_err(|_| ()).unwrap();
 
                // Node B --> Node A: funding signed
-               let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&keys_provider, &&logger);
+               let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&keys_provider, &&logger).unwrap();
 
                // Now disconnect the two nodes and check that the commitment point in
                // Node B's channel_reestablish message is sane.
@@ -7630,55 +7664,55 @@ mod tests {
                let mut config_101_percent = UserConfig::default();
                config_101_percent.channel_handshake_config.max_inbound_htlc_value_in_flight_percent_of_channel = 101;
 
-               // Test that `new_outbound` creates a channel with the correct value for
+               // Test that `OutboundV1Channel::new` creates a channel with the correct value for
                // `holder_max_htlc_value_in_flight_msat`, when configured with a valid percentage value,
                // which is set to the lower bound + 1 (2%) of the `channel_value`.
-               let chan_1 = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_2_percent), 10000000, 100000, 42, &config_2_percent, 0, 42).unwrap();
+               let chan_1 = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_2_percent), 10000000, 100000, 42, &config_2_percent, 0, 42).unwrap();
                let chan_1_value_msat = chan_1.context.channel_value_satoshis * 1000;
                assert_eq!(chan_1.context.holder_max_htlc_value_in_flight_msat, (chan_1_value_msat as f64 * 0.02) as u64);
 
                // Test with the upper bound - 1 of valid values (99%).
-               let chan_2 = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_99_percent), 10000000, 100000, 42, &config_99_percent, 0, 42).unwrap();
+               let chan_2 = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_99_percent), 10000000, 100000, 42, &config_99_percent, 0, 42).unwrap();
                let chan_2_value_msat = chan_2.context.channel_value_satoshis * 1000;
                assert_eq!(chan_2.context.holder_max_htlc_value_in_flight_msat, (chan_2_value_msat as f64 * 0.99) as u64);
 
                let chan_1_open_channel_msg = chan_1.get_open_channel(genesis_block(network).header.block_hash());
 
-               // Test that `new_from_req` creates a channel with the correct value for
+               // Test that `InboundV1Channel::new` creates a channel with the correct value for
                // `holder_max_htlc_value_in_flight_msat`, when configured with a valid percentage value,
                // which is set to the lower bound - 1 (2%) of the `channel_value`.
-               let chan_3 = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_2_percent), &channelmanager::provided_init_features(&config_2_percent), &chan_1_open_channel_msg, 7, &config_2_percent, 0, &&logger, 42).unwrap();
+               let chan_3 = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_2_percent), &channelmanager::provided_init_features(&config_2_percent), &chan_1_open_channel_msg, 7, &config_2_percent, 0, &&logger, 42).unwrap();
                let chan_3_value_msat = chan_3.context.channel_value_satoshis * 1000;
                assert_eq!(chan_3.context.holder_max_htlc_value_in_flight_msat, (chan_3_value_msat as f64 * 0.02) as u64);
 
                // Test with the upper bound - 1 of valid values (99%).
-               let chan_4 = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_99_percent), &channelmanager::provided_init_features(&config_99_percent), &chan_1_open_channel_msg, 7, &config_99_percent, 0, &&logger, 42).unwrap();
+               let chan_4 = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_99_percent), &channelmanager::provided_init_features(&config_99_percent), &chan_1_open_channel_msg, 7, &config_99_percent, 0, &&logger, 42).unwrap();
                let chan_4_value_msat = chan_4.context.channel_value_satoshis * 1000;
                assert_eq!(chan_4.context.holder_max_htlc_value_in_flight_msat, (chan_4_value_msat as f64 * 0.99) as u64);
 
-               // Test that `new_outbound` uses the lower bound of the configurable percentage values (1%)
+               // Test that `OutboundV1Channel::new` uses the lower bound of the configurable percentage values (1%)
                // if `max_inbound_htlc_value_in_flight_percent_of_channel` is set to a value less than 1.
-               let chan_5 = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_0_percent), 10000000, 100000, 42, &config_0_percent, 0, 42).unwrap();
+               let chan_5 = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_0_percent), 10000000, 100000, 42, &config_0_percent, 0, 42).unwrap();
                let chan_5_value_msat = chan_5.context.channel_value_satoshis * 1000;
                assert_eq!(chan_5.context.holder_max_htlc_value_in_flight_msat, (chan_5_value_msat as f64 * 0.01) as u64);
 
-               // Test that `new_outbound` uses the upper bound of the configurable percentage values
+               // Test that `OutboundV1Channel::new` uses the upper bound of the configurable percentage values
                // (100%) if `max_inbound_htlc_value_in_flight_percent_of_channel` is set to a larger value
                // than 100.
-               let chan_6 = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_101_percent), 10000000, 100000, 42, &config_101_percent, 0, 42).unwrap();
+               let chan_6 = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_101_percent), 10000000, 100000, 42, &config_101_percent, 0, 42).unwrap();
                let chan_6_value_msat = chan_6.context.channel_value_satoshis * 1000;
                assert_eq!(chan_6.context.holder_max_htlc_value_in_flight_msat, chan_6_value_msat);
 
-               // Test that `new_from_req` uses the lower bound of the configurable percentage values (1%)
+               // Test that `InboundV1Channel::new` uses the lower bound of the configurable percentage values (1%)
                // if `max_inbound_htlc_value_in_flight_percent_of_channel` is set to a value less than 1.
-               let chan_7 = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_0_percent), &channelmanager::provided_init_features(&config_0_percent), &chan_1_open_channel_msg, 7, &config_0_percent, 0, &&logger, 42).unwrap();
+               let chan_7 = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_0_percent), &channelmanager::provided_init_features(&config_0_percent), &chan_1_open_channel_msg, 7, &config_0_percent, 0, &&logger, 42).unwrap();
                let chan_7_value_msat = chan_7.context.channel_value_satoshis * 1000;
                assert_eq!(chan_7.context.holder_max_htlc_value_in_flight_msat, (chan_7_value_msat as f64 * 0.01) as u64);
 
-               // Test that `new_from_req` uses the upper bound of the configurable percentage values
+               // Test that `InboundV1Channel::new` uses the upper bound of the configurable percentage values
                // (100%) if `max_inbound_htlc_value_in_flight_percent_of_channel` is set to a larger value
                // than 100.
-               let chan_8 = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_101_percent), &channelmanager::provided_init_features(&config_101_percent), &chan_1_open_channel_msg, 7, &config_101_percent, 0, &&logger, 42).unwrap();
+               let chan_8 = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&config_101_percent), &channelmanager::provided_init_features(&config_101_percent), &chan_1_open_channel_msg, 7, &config_101_percent, 0, &&logger, 42).unwrap();
                let chan_8_value_msat = chan_8.context.channel_value_satoshis * 1000;
                assert_eq!(chan_8.context.holder_max_htlc_value_in_flight_msat, chan_8_value_msat);
        }
@@ -7686,7 +7720,7 @@ mod tests {
        #[test]
        fn test_configured_holder_selected_channel_reserve_satoshis() {
 
-               // Test that `new_outbound` and `new_from_req` create a channel with the correct
+               // Test that `OutboundV1Channel::new` and `InboundV1Channel::new` create a channel with the correct
                // channel reserves, when `their_channel_reserve_proportional_millionths` is configured.
                test_self_and_counterparty_channel_reserve(10_000_000, 0.02, 0.02);
 
@@ -7718,7 +7752,7 @@ mod tests {
 
                let mut outbound_node_config = UserConfig::default();
                outbound_node_config.channel_handshake_config.their_channel_reserve_proportional_millionths = (outbound_selected_channel_reserve_perc * 1_000_000.0) as u32;
-               let chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&&fee_est, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&outbound_node_config), channel_value_satoshis, 100_000, 42, &outbound_node_config, 0, 42).unwrap();
+               let chan = OutboundV1Channel::<EnforcingSigner>::new(&&fee_est, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&outbound_node_config), channel_value_satoshis, 100_000, 42, &outbound_node_config, 0, 42).unwrap();
 
                let expected_outbound_selected_chan_reserve = cmp::max(MIN_THEIR_CHAN_RESERVE_SATOSHIS, (chan.context.channel_value_satoshis as f64 * outbound_selected_channel_reserve_perc) as u64);
                assert_eq!(chan.context.holder_selected_channel_reserve_satoshis, expected_outbound_selected_chan_reserve);
@@ -7728,7 +7762,7 @@ mod tests {
                inbound_node_config.channel_handshake_config.their_channel_reserve_proportional_millionths = (inbound_selected_channel_reserve_perc * 1_000_000.0) as u32;
 
                if outbound_selected_channel_reserve_perc + inbound_selected_channel_reserve_perc < 1.0 {
-                       let chan_inbound_node = InboundV1Channel::<EnforcingSigner>::new_from_req(&&fee_est, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&inbound_node_config), &channelmanager::provided_init_features(&outbound_node_config), &chan_open_channel_msg, 7, &inbound_node_config, 0, &&logger, 42).unwrap();
+                       let chan_inbound_node = InboundV1Channel::<EnforcingSigner>::new(&&fee_est, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&inbound_node_config), &channelmanager::provided_init_features(&outbound_node_config), &chan_open_channel_msg, 7, &inbound_node_config, 0, &&logger, 42).unwrap();
 
                        let expected_inbound_selected_chan_reserve = cmp::max(MIN_THEIR_CHAN_RESERVE_SATOSHIS, (chan.context.channel_value_satoshis as f64 * inbound_selected_channel_reserve_perc) as u64);
 
@@ -7736,7 +7770,7 @@ mod tests {
                        assert_eq!(chan_inbound_node.context.counterparty_selected_channel_reserve_satoshis.unwrap(), expected_outbound_selected_chan_reserve);
                } else {
                        // Channel Negotiations failed
-                       let result = InboundV1Channel::<EnforcingSigner>::new_from_req(&&fee_est, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&inbound_node_config), &channelmanager::provided_init_features(&outbound_node_config), &chan_open_channel_msg, 7, &inbound_node_config, 0, &&logger, 42);
+                       let result = InboundV1Channel::<EnforcingSigner>::new(&&fee_est, &&keys_provider, &&keys_provider, inbound_node_id, &channelmanager::provided_channel_type_features(&inbound_node_config), &channelmanager::provided_init_features(&outbound_node_config), &chan_open_channel_msg, 7, &inbound_node_config, 0, &&logger, 42);
                        assert!(result.is_err());
                }
        }
@@ -7744,19 +7778,42 @@ mod tests {
        #[test]
        fn channel_update() {
                let feeest = LowerBoundedFeeEstimator::new(&TestFeeEstimator{fee_est: 15000});
+               let logger = test_utils::TestLogger::new();
                let secp_ctx = Secp256k1::new();
                let seed = [42; 32];
                let network = Network::Testnet;
+               let best_block = BestBlock::from_network(network);
                let chain_hash = genesis_block(network).header.block_hash();
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
 
-               // Create a channel.
+               // Create Node A's channel pointing to Node B's pubkey
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
-               assert!(node_a_chan.context.counterparty_forwarding_info.is_none());
-               assert_eq!(node_a_chan.context.holder_htlc_minimum_msat, 1); // the default
-               assert!(node_a_chan.context.counterparty_forwarding_info().is_none());
+               let mut node_a_chan = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+
+               // Create Node B's channel by receiving Node A's open_channel message
+               // Make sure A's dust limit is as we expect.
+               let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
+               let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
+               let mut node_b_chan = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42).unwrap();
+
+               // Node B --> Node A: accept channel, explicitly setting B's dust limit.
+               let mut accept_channel_msg = node_b_chan.accept_inbound_channel(0);
+               accept_channel_msg.dust_limit_satoshis = 546;
+               node_a_chan.accept_channel(&accept_channel_msg, &config.channel_handshake_limits, &channelmanager::provided_init_features(&config)).unwrap();
+               node_a_chan.context.holder_dust_limit_satoshis = 1560;
+
+               // Node A --> Node B: funding created
+               let output_script = node_a_chan.context.get_funding_redeemscript();
+               let tx = Transaction { version: 1, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: vec![TxOut {
+                       value: 10000000, script_pubkey: output_script.clone(),
+               }]};
+               let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
+               let (mut node_a_chan, funding_created_msg) = node_a_chan.get_outbound_funding_created(tx.clone(), funding_outpoint, &&logger).map_err(|_| ()).unwrap();
+               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).map_err(|_| ()).unwrap();
+
+               // Node B --> Node A: funding signed
+               let _ = node_a_chan.funding_signed(&funding_signed_msg, best_block, &&keys_provider, &&logger).unwrap();
 
                // Make sure that receiving a channel update will update the Channel as expected.
                let update = ChannelUpdate {
@@ -7832,7 +7889,7 @@ mod tests {
                let counterparty_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let mut config = UserConfig::default();
                config.channel_handshake_config.announced_channel = false;
-               let mut chan = Channel::<InMemorySigner>::new_outbound(&LowerBoundedFeeEstimator::new(&feeest), &&keys_provider, &&keys_provider, counterparty_node_id, &channelmanager::provided_init_features(&config), 10_000_000, 0, 42, &config, 0, 42).unwrap(); // Nothing uses their network key in this test
+               let mut chan = OutboundV1Channel::<InMemorySigner>::new(&LowerBoundedFeeEstimator::new(&feeest), &&keys_provider, &&keys_provider, counterparty_node_id, &channelmanager::provided_init_features(&config), 10_000_000, 0, 42, &config, 0, 42).unwrap(); // Nothing uses their network key in this test
                chan.context.holder_dust_limit_satoshis = 546;
                chan.context.counterparty_selected_channel_reserve_satoshis = Some(0); // Filled in in accept_channel
 
@@ -8551,7 +8608,7 @@ mod tests {
 
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
                let config = UserConfig::default();
-               let node_a_chan = OutboundV1Channel::<EnforcingSigner>::new_outbound(&feeest, &&keys_provider, &&keys_provider,
+               let node_a_chan = OutboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider,
                        node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
 
                let mut channel_type_features = ChannelTypeFeatures::only_static_remote_key();
@@ -8560,7 +8617,7 @@ mod tests {
                let mut open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
                open_channel_msg.channel_type = Some(channel_type_features);
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
-               let res = InboundV1Channel::<EnforcingSigner>::new_from_req(&feeest, &&keys_provider, &&keys_provider,
+               let res = InboundV1Channel::<EnforcingSigner>::new(&feeest, &&keys_provider, &&keys_provider,
                        node_b_node_id, &channelmanager::provided_channel_type_features(&config),
                        &channelmanager::provided_init_features(&config), &open_channel_msg, 7, &config, 0, &&logger, 42);
                assert!(res.is_ok());
@@ -8585,7 +8642,7 @@ mod tests {
 
                // It is not enough for just the initiator to signal `option_anchors_zero_fee_htlc_tx`, both
                // need to signal it.
-               let channel_a = OutboundV1Channel::<EnforcingSigner>::new_outbound(
+               let channel_a = OutboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
                        &channelmanager::provided_init_features(&UserConfig::default()), 10000000, 100000, 42,
                        &config, 0, 42
@@ -8596,13 +8653,13 @@ mod tests {
                expected_channel_type.set_static_remote_key_required();
                expected_channel_type.set_anchors_zero_fee_htlc_tx_required();
 
-               let channel_a = OutboundV1Channel::<EnforcingSigner>::new_outbound(
+               let channel_a = OutboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
                        &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
                ).unwrap();
 
                let open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
-               let channel_b = InboundV1Channel::<EnforcingSigner>::new_from_req(
+               let channel_b = InboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
                        &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config),
                        &open_channel_msg, 7, &config, 0, &&logger, 42
@@ -8634,7 +8691,7 @@ mod tests {
                let raw_init_features = static_remote_key_required | simple_anchors_required;
                let init_features_with_simple_anchors = InitFeatures::from_le_bytes(raw_init_features.to_le_bytes().to_vec());
 
-               let channel_a = OutboundV1Channel::<EnforcingSigner>::new_outbound(
+               let channel_a = OutboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
                        &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
                ).unwrap();
@@ -8645,7 +8702,7 @@ mod tests {
 
                // Since A supports both `static_remote_key` and `option_anchors`, but B only accepts
                // `static_remote_key`, it will fail the channel.
-               let channel_b = InboundV1Channel::<EnforcingSigner>::new_from_req(
+               let channel_b = InboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
                        &channelmanager::provided_channel_type_features(&config), &init_features_with_simple_anchors,
                        &open_channel_msg, 7, &config, 0, &&logger, 42
@@ -8675,13 +8732,13 @@ mod tests {
                let simple_anchors_raw_features = static_remote_key_required | simple_anchors_required;
                let simple_anchors_init = InitFeatures::from_le_bytes(simple_anchors_raw_features.to_le_bytes().to_vec());
                let simple_anchors_channel_type = ChannelTypeFeatures::from_le_bytes(simple_anchors_raw_features.to_le_bytes().to_vec());
-               assert!(simple_anchors_init.requires_unknown_bits());
-               assert!(simple_anchors_channel_type.requires_unknown_bits());
+               assert!(!simple_anchors_init.requires_unknown_bits());
+               assert!(!simple_anchors_channel_type.requires_unknown_bits());
 
                // First, we'll try to open a channel between A and B where A requests a channel type for
                // the original `option_anchors` feature (non zero fee htlc tx). This should be rejected by
                // B as it's not supported by LDK.
-               let channel_a = OutboundV1Channel::<EnforcingSigner>::new_outbound(
+               let channel_a = OutboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
                        &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
                ).unwrap();
@@ -8689,7 +8746,7 @@ mod tests {
                let mut open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
                open_channel_msg.channel_type = Some(simple_anchors_channel_type.clone());
 
-               let res = InboundV1Channel::<EnforcingSigner>::new_from_req(
+               let res = InboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
                        &channelmanager::provided_channel_type_features(&config), &simple_anchors_init,
                        &open_channel_msg, 7, &config, 0, &&logger, 42
@@ -8700,14 +8757,14 @@ mod tests {
                // `anchors_zero_fee_htlc_tx`. B is malicious and tries to downgrade the channel type to the
                // original `option_anchors` feature, which should be rejected by A as it's not supported by
                // LDK.
-               let mut channel_a = OutboundV1Channel::<EnforcingSigner>::new_outbound(
+               let mut channel_a = OutboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b, &simple_anchors_init,
                        10000000, 100000, 42, &config, 0, 42
                ).unwrap();
 
                let open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
 
-               let channel_b = InboundV1Channel::<EnforcingSigner>::new_from_req(
+               let channel_b = InboundV1Channel::<EnforcingSigner>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
                        &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config),
                        &open_channel_msg, 7, &config, 0, &&logger, 42