Expose `skimmed_fee_msat` in `PaymentForwarded`
[rust-lightning] / lightning / src / ln / channel.rs
index 55e56be2a79377079377591f14ad1fef33311f17..e56fa978953b2d9d90769ff172691d341017741f 100644 (file)
@@ -7,9 +7,11 @@
 // You may not use this file except in accordance with one or both of these
 // licenses.
 
-use bitcoin::blockdata::script::{Script,Builder};
-use bitcoin::blockdata::transaction::{Transaction, EcdsaSighashType};
-use bitcoin::util::sighash;
+use bitcoin::blockdata::constants::ChainHash;
+use bitcoin::blockdata::script::{Script, ScriptBuf, Builder};
+use bitcoin::blockdata::transaction::Transaction;
+use bitcoin::sighash;
+use bitcoin::sighash::EcdsaSighashType;
 use bitcoin::consensus::encode;
 
 use bitcoin::hashes::Hash;
@@ -35,11 +37,12 @@ use crate::chain::BestBlock;
 use crate::chain::chaininterface::{FeeEstimator, ConfirmationTarget, LowerBoundedFeeEstimator};
 use crate::chain::channelmonitor::{ChannelMonitor, ChannelMonitorUpdate, ChannelMonitorUpdateStep, LATENCY_GRACE_PERIOD_BLOCKS, CLOSED_CHANNEL_UPDATE_ID};
 use crate::chain::transaction::{OutPoint, TransactionData};
-use crate::sign::{EcdsaChannelSigner, WriteableEcdsaChannelSigner, EntropySource, ChannelSigner, SignerProvider, NodeSigner, Recipient};
+use crate::sign::ecdsa::{EcdsaChannelSigner, WriteableEcdsaChannelSigner};
+use crate::sign::{EntropySource, ChannelSigner, SignerProvider, NodeSigner, Recipient};
 use crate::events::ClosureReason;
 use crate::routing::gossip::NodeId;
-use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer, VecWriter};
-use crate::util::logger::Logger;
+use crate::util::ser::{Readable, ReadableArgs, Writeable, Writer};
+use crate::util::logger::{Logger, Record, WithContext};
 use crate::util::errors::APIError;
 use crate::util::config::{UserConfig, ChannelConfig, LegacyChannelConfig, ChannelHandshakeConfig, ChannelHandshakeLimits, MaxDustHTLCExposure};
 use crate::util::scid_utils::scid_from_parts;
@@ -47,12 +50,14 @@ use crate::util::scid_utils::scid_from_parts;
 use crate::io;
 use crate::prelude::*;
 use core::{cmp,mem,fmt};
+use core::convert::TryInto;
 use core::ops::Deref;
 #[cfg(any(test, fuzzing, debug_assertions))]
 use crate::sync::Mutex;
-use bitcoin::hashes::hex::ToHex;
 use crate::sign::type_resolver::ChannelSignerType;
 
+use super::channel_keys::{DelayedPaymentBasepoint, HtlcBasepoint, RevocationBasepoint};
+
 #[cfg(test)]
 pub struct ChannelValueStat {
        pub value_to_self_msat: u64,
@@ -66,6 +71,8 @@ pub struct ChannelValueStat {
 }
 
 pub struct AvailableBalances {
+       /// The amount that would go to us if we close the channel, ignoring any on-chain fees.
+       pub balance_msat: u64,
        /// Total amount available for our counterparty to send to us.
        pub inbound_capacity_msat: u64,
        /// Total amount available for us to send to our counterparty.
@@ -159,6 +166,7 @@ struct InboundHTLCOutput {
        state: InboundHTLCState,
 }
 
+#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
 enum OutboundHTLCState {
        /// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
        /// created it we would have put it in the holding cell instead). When they next revoke_and_ack
@@ -192,6 +200,7 @@ enum OutboundHTLCState {
 }
 
 #[derive(Clone)]
+#[cfg_attr(test, derive(Debug, PartialEq))]
 enum OutboundHTLCOutcome {
        /// LDK version 0.0.105+ will always fill in the preimage here.
        Success(Option<PaymentPreimage>),
@@ -216,6 +225,7 @@ impl<'a> Into<Option<&'a HTLCFailReason>> for &'a OutboundHTLCOutcome {
        }
 }
 
+#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
 struct OutboundHTLCOutput {
        htlc_id: u64,
        amount_msat: u64,
@@ -223,10 +233,12 @@ struct OutboundHTLCOutput {
        payment_hash: PaymentHash,
        state: OutboundHTLCState,
        source: HTLCSource,
+       blinding_point: Option<PublicKey>,
        skimmed_fee_msat: Option<u64>,
 }
 
 /// See AwaitingRemoteRevoke ChannelState for more info
+#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
 enum HTLCUpdateAwaitingACK {
        AddHTLC { // TODO: Time out if we're getting close to cltv_expiry
                // always outbound
@@ -237,6 +249,7 @@ enum HTLCUpdateAwaitingACK {
                onion_routing_packet: msgs::OnionPacket,
                // The extra fee we're skimming off the top of this HTLC.
                skimmed_fee_msat: Option<u64>,
+               blinding_point: Option<PublicKey>,
        },
        ClaimHTLC {
                payment_preimage: PaymentPreimage,
@@ -246,78 +259,325 @@ enum HTLCUpdateAwaitingACK {
                htlc_id: u64,
                err_packet: msgs::OnionErrorPacket,
        },
+       FailMalformedHTLC {
+               htlc_id: u64,
+               failure_code: u16,
+               sha256_of_onion: [u8; 32],
+       },
 }
 
-/// There are a few "states" and then a number of flags which can be applied:
-/// We first move through init with `OurInitSent` -> `TheirInitSent` -> `FundingCreated` -> `FundingSent`.
-/// `TheirChannelReady` and `OurChannelReady` then get set on `FundingSent`, and when both are set we
-/// move on to `ChannelReady`.
-/// Note that `PeerDisconnected` can be set on both `ChannelReady` and `FundingSent`.
-/// `ChannelReady` can then get all remaining flags set on it, until we finish shutdown, then we
-/// move on to `ShutdownComplete`, at which point most calls into this channel are disallowed.
+macro_rules! define_state_flags {
+       ($flag_type_doc: expr, $flag_type: ident, [$(($flag_doc: expr, $flag: ident, $value: expr, $get: ident, $set: ident, $clear: ident)),+], $extra_flags: expr) => {
+               #[doc = $flag_type_doc]
+               #[derive(Copy, Clone, Debug, PartialEq, PartialOrd, Eq)]
+               struct $flag_type(u32);
+
+               impl $flag_type {
+                       $(
+                               #[doc = $flag_doc]
+                               const $flag: $flag_type = $flag_type($value);
+                       )*
+
+                       /// All flags that apply to the specified [`ChannelState`] variant.
+                       #[allow(unused)]
+                       const ALL: $flag_type = Self($(Self::$flag.0 | )* $extra_flags);
+
+                       #[allow(unused)]
+                       fn new() -> Self { Self(0) }
+
+                       #[allow(unused)]
+                       fn from_u32(flags: u32) -> Result<Self, ()> {
+                               if flags & !Self::ALL.0 != 0 {
+                                       Err(())
+                               } else {
+                                       Ok($flag_type(flags))
+                               }
+                       }
+
+                       #[allow(unused)]
+                       fn is_empty(&self) -> bool { self.0 == 0 }
+                       #[allow(unused)]
+                       fn is_set(&self, flag: Self) -> bool { *self & flag == flag }
+                       #[allow(unused)]
+                       fn set(&mut self, flag: Self) { *self |= flag }
+                       #[allow(unused)]
+                       fn clear(&mut self, flag: Self) -> Self { self.0 &= !flag.0; *self }
+               }
+
+               $(
+                       define_state_flags!($flag_type, Self::$flag, $get, $set, $clear);
+               )*
+
+               impl core::ops::BitOr for $flag_type {
+                       type Output = Self;
+                       fn bitor(self, rhs: Self) -> Self::Output { Self(self.0 | rhs.0) }
+               }
+               impl core::ops::BitOrAssign for $flag_type {
+                       fn bitor_assign(&mut self, rhs: Self) { self.0 |= rhs.0; }
+               }
+               impl core::ops::BitAnd for $flag_type {
+                       type Output = Self;
+                       fn bitand(self, rhs: Self) -> Self::Output { Self(self.0 & rhs.0) }
+               }
+               impl core::ops::BitAndAssign for $flag_type {
+                       fn bitand_assign(&mut self, rhs: Self) { self.0 &= rhs.0; }
+               }
+       };
+       ($flag_type_doc: expr, $flag_type: ident, $flags: tt) => {
+               define_state_flags!($flag_type_doc, $flag_type, $flags, 0);
+       };
+       ($flag_type: ident, $flag: expr, $get: ident, $set: ident, $clear: ident) => {
+               impl $flag_type {
+                       #[allow(unused)]
+                       fn $get(&self) -> bool { self.is_set($flag_type::new() | $flag) }
+                       #[allow(unused)]
+                       fn $set(&mut self) { self.set($flag_type::new() | $flag) }
+                       #[allow(unused)]
+                       fn $clear(&mut self) -> Self { self.clear($flag_type::new() | $flag) }
+               }
+       };
+       ($flag_type_doc: expr, FUNDED_STATE, $flag_type: ident, $flags: tt) => {
+               define_state_flags!($flag_type_doc, $flag_type, $flags, FundedStateFlags::ALL.0);
+
+               define_state_flags!($flag_type, FundedStateFlags::PEER_DISCONNECTED,
+                       is_peer_disconnected, set_peer_disconnected, clear_peer_disconnected);
+               define_state_flags!($flag_type, FundedStateFlags::MONITOR_UPDATE_IN_PROGRESS,
+                       is_monitor_update_in_progress, set_monitor_update_in_progress, clear_monitor_update_in_progress);
+               define_state_flags!($flag_type, FundedStateFlags::REMOTE_SHUTDOWN_SENT,
+                       is_remote_shutdown_sent, set_remote_shutdown_sent, clear_remote_shutdown_sent);
+               define_state_flags!($flag_type, FundedStateFlags::LOCAL_SHUTDOWN_SENT,
+                       is_local_shutdown_sent, set_local_shutdown_sent, clear_local_shutdown_sent);
+
+               impl core::ops::BitOr<FundedStateFlags> for $flag_type {
+                       type Output = Self;
+                       fn bitor(self, rhs: FundedStateFlags) -> Self::Output { Self(self.0 | rhs.0) }
+               }
+               impl core::ops::BitOrAssign<FundedStateFlags> for $flag_type {
+                       fn bitor_assign(&mut self, rhs: FundedStateFlags) { self.0 |= rhs.0; }
+               }
+               impl core::ops::BitAnd<FundedStateFlags> for $flag_type {
+                       type Output = Self;
+                       fn bitand(self, rhs: FundedStateFlags) -> Self::Output { Self(self.0 & rhs.0) }
+               }
+               impl core::ops::BitAndAssign<FundedStateFlags> for $flag_type {
+                       fn bitand_assign(&mut self, rhs: FundedStateFlags) { self.0 &= rhs.0; }
+               }
+               impl PartialEq<FundedStateFlags> for $flag_type {
+                       fn eq(&self, other: &FundedStateFlags) -> bool { self.0 == other.0 }
+               }
+               impl From<FundedStateFlags> for $flag_type {
+                       fn from(flags: FundedStateFlags) -> Self { Self(flags.0) }
+               }
+       };
+}
+
+/// We declare all the states/flags here together to help determine which bits are still available
+/// to choose.
+mod state_flags {
+       pub const OUR_INIT_SENT: u32 = 1 << 0;
+       pub const THEIR_INIT_SENT: u32 = 1 << 1;
+       pub const FUNDING_NEGOTIATED: u32 = 1 << 2;
+       pub const AWAITING_CHANNEL_READY: u32 = 1 << 3;
+       pub const THEIR_CHANNEL_READY: u32 = 1 << 4;
+       pub const OUR_CHANNEL_READY: u32 = 1 << 5;
+       pub const CHANNEL_READY: u32 = 1 << 6;
+       pub const PEER_DISCONNECTED: u32 = 1 << 7;
+       pub const MONITOR_UPDATE_IN_PROGRESS: u32 = 1 << 8;
+       pub const AWAITING_REMOTE_REVOKE: u32 = 1 << 9;
+       pub const REMOTE_SHUTDOWN_SENT: u32 = 1 << 10;
+       pub const LOCAL_SHUTDOWN_SENT: u32 = 1 << 11;
+       pub const SHUTDOWN_COMPLETE: u32 = 1 << 12;
+       pub const WAITING_FOR_BATCH: u32 = 1 << 13;
+}
+
+define_state_flags!(
+       "Flags that apply to all [`ChannelState`] variants in which the channel is funded.",
+       FundedStateFlags, [
+               ("Indicates the remote side is considered \"disconnected\" and no updates are allowed \
+                       until after we've done a `channel_reestablish` dance.", PEER_DISCONNECTED, state_flags::PEER_DISCONNECTED,
+                       is_peer_disconnected, set_peer_disconnected, clear_peer_disconnected),
+               ("Indicates the user has told us a `ChannelMonitor` update is pending async persistence \
+                       somewhere and we should pause sending any outbound messages until they've managed to \
+                       complete it.", MONITOR_UPDATE_IN_PROGRESS, state_flags::MONITOR_UPDATE_IN_PROGRESS,
+                       is_monitor_update_in_progress, set_monitor_update_in_progress, clear_monitor_update_in_progress),
+               ("Indicates we received a `shutdown` message from the remote end. If set, they may not add \
+                       any new HTLCs to the channel, and we are expected to respond with our own `shutdown` \
+                       message when possible.", REMOTE_SHUTDOWN_SENT, state_flags::REMOTE_SHUTDOWN_SENT,
+                       is_remote_shutdown_sent, set_remote_shutdown_sent, clear_remote_shutdown_sent),
+               ("Indicates we sent a `shutdown` message. At this point, we may not add any new HTLCs to \
+                       the channel.", LOCAL_SHUTDOWN_SENT, state_flags::LOCAL_SHUTDOWN_SENT,
+                       is_local_shutdown_sent, set_local_shutdown_sent, clear_local_shutdown_sent)
+       ]
+);
+
+define_state_flags!(
+       "Flags that only apply to [`ChannelState::NegotiatingFunding`].",
+       NegotiatingFundingFlags, [
+               ("Indicates we have (or are prepared to) send our `open_channel`/`accept_channel` message.",
+                       OUR_INIT_SENT, state_flags::OUR_INIT_SENT, is_our_init_sent, set_our_init_sent, clear_our_init_sent),
+               ("Indicates we have received their `open_channel`/`accept_channel` message.",
+                       THEIR_INIT_SENT, state_flags::THEIR_INIT_SENT, is_their_init_sent, set_their_init_sent, clear_their_init_sent)
+       ]
+);
+
+define_state_flags!(
+       "Flags that only apply to [`ChannelState::AwaitingChannelReady`].",
+       FUNDED_STATE, AwaitingChannelReadyFlags, [
+               ("Indicates they sent us a `channel_ready` message. Once both `THEIR_CHANNEL_READY` and \
+                       `OUR_CHANNEL_READY` are set, our state moves on to `ChannelReady`.",
+                       THEIR_CHANNEL_READY, state_flags::THEIR_CHANNEL_READY,
+                       is_their_channel_ready, set_their_channel_ready, clear_their_channel_ready),
+               ("Indicates we sent them a `channel_ready` message. Once both `THEIR_CHANNEL_READY` and \
+                       `OUR_CHANNEL_READY` are set, our state moves on to `ChannelReady`.",
+                       OUR_CHANNEL_READY, state_flags::OUR_CHANNEL_READY,
+                       is_our_channel_ready, set_our_channel_ready, clear_our_channel_ready),
+               ("Indicates the channel was funded in a batch and the broadcast of the funding transaction \
+                       is being held until all channels in the batch have received `funding_signed` and have \
+                       their monitors persisted.", WAITING_FOR_BATCH, state_flags::WAITING_FOR_BATCH,
+                       is_waiting_for_batch, set_waiting_for_batch, clear_waiting_for_batch)
+       ]
+);
+
+define_state_flags!(
+       "Flags that only apply to [`ChannelState::ChannelReady`].",
+       FUNDED_STATE, ChannelReadyFlags, [
+               ("Indicates that we have sent a `commitment_signed` but are awaiting the responding \
+                       `revoke_and_ack` message. During this period, we can't generate new `commitment_signed` \
+                       messages as we'd be unable to determine which HTLCs they included in their `revoke_and_ack` \
+                       implicit ACK, so instead we have to hold them away temporarily to be sent later.",
+                       AWAITING_REMOTE_REVOKE, state_flags::AWAITING_REMOTE_REVOKE,
+                       is_awaiting_remote_revoke, set_awaiting_remote_revoke, clear_awaiting_remote_revoke)
+       ]
+);
+
+// Note that the order of this enum is implicitly defined by where each variant is placed. Take this
+// into account when introducing new states and update `test_channel_state_order` accordingly.
+#[derive(Copy, Clone, Debug, PartialEq, PartialOrd, Eq)]
 enum ChannelState {
-       /// Implies we have (or are prepared to) send our open_channel/accept_channel message
-       OurInitSent = 1 << 0,
-       /// Implies we have received their `open_channel`/`accept_channel` message
-       TheirInitSent = 1 << 1,
-       /// We have sent `funding_created` and are awaiting a `funding_signed` to advance to `FundingSent`.
-       /// Note that this is nonsense for an inbound channel as we immediately generate `funding_signed`
-       /// upon receipt of `funding_created`, so simply skip this state.
-       FundingCreated = 4,
-       /// Set when we have received/sent `funding_created` and `funding_signed` and are thus now waiting
-       /// on the funding transaction to confirm. The `ChannelReady` flags are set to indicate when we
-       /// and our counterparty consider the funding transaction confirmed.
-       FundingSent = 8,
-       /// Flag which can be set on `FundingSent` to indicate they sent us a `channel_ready` message.
-       /// Once both `TheirChannelReady` and `OurChannelReady` are set, state moves on to `ChannelReady`.
-       TheirChannelReady = 1 << 4,
-       /// Flag which can be set on `FundingSent` to indicate we sent them a `channel_ready` message.
-       /// Once both `TheirChannelReady` and `OurChannelReady` are set, state moves on to `ChannelReady`.
-       OurChannelReady = 1 << 5,
-       ChannelReady = 64,
-       /// Flag which is set on `ChannelReady` and `FundingSent` indicating remote side is considered
-       /// "disconnected" and no updates are allowed until after we've done a `channel_reestablish`
-       /// dance.
-       PeerDisconnected = 1 << 7,
-       /// Flag which is set on `ChannelReady`, FundingCreated, and `FundingSent` indicating the user has
-       /// told us a `ChannelMonitor` update is pending async persistence somewhere and we should pause
-       /// sending any outbound messages until they've managed to finish.
-       MonitorUpdateInProgress = 1 << 8,
-       /// Flag which implies that we have sent a commitment_signed but are awaiting the responding
-       /// revoke_and_ack message. During this time period, we can't generate new commitment_signed
-       /// messages as then we will be unable to determine which HTLCs they included in their
-       /// revoke_and_ack implicit ACK, so instead we have to hold them away temporarily to be sent
-       /// later.
-       /// Flag is set on `ChannelReady`.
-       AwaitingRemoteRevoke = 1 << 9,
-       /// Flag which is set on `ChannelReady` or `FundingSent` after receiving a shutdown message from
-       /// the remote end. If set, they may not add any new HTLCs to the channel, and we are expected
-       /// to respond with our own shutdown message when possible.
-       RemoteShutdownSent = 1 << 10,
-       /// Flag which is set on `ChannelReady` or `FundingSent` after sending a shutdown message. At this
-       /// point, we may not add any new HTLCs to the channel.
-       LocalShutdownSent = 1 << 11,
-       /// We've successfully negotiated a closing_signed dance. At this point ChannelManager is about
-       /// to drop us, but we store this anyway.
-       ShutdownComplete = 4096,
-       /// Flag which is set on `FundingSent` to indicate this channel is funded in a batch and the
-       /// broadcasting of the funding transaction is being held until all channels in the batch
-       /// have received funding_signed and have their monitors persisted.
-       WaitingForBatch = 1 << 13,
+       /// We are negotiating the parameters required for the channel prior to funding it.
+       NegotiatingFunding(NegotiatingFundingFlags),
+       /// We have sent `funding_created` and are awaiting a `funding_signed` to advance to
+       /// `AwaitingChannelReady`. Note that this is nonsense for an inbound channel as we immediately generate
+       /// `funding_signed` upon receipt of `funding_created`, so simply skip this state.
+       FundingNegotiated,
+       /// We've received/sent `funding_created` and `funding_signed` and are thus now waiting on the
+       /// funding transaction to confirm.
+       AwaitingChannelReady(AwaitingChannelReadyFlags),
+       /// Both we and our counterparty consider the funding transaction confirmed and the channel is
+       /// now operational.
+       ChannelReady(ChannelReadyFlags),
+       /// We've successfully negotiated a `closing_signed` dance. At this point, the `ChannelManager`
+       /// is about to drop us, but we store this anyway.
+       ShutdownComplete,
+}
+
+macro_rules! impl_state_flag {
+       ($get: ident, $set: ident, $clear: ident, [$($state: ident),+]) => {
+               #[allow(unused)]
+               fn $get(&self) -> bool {
+                       match self {
+                               $(
+                                       ChannelState::$state(flags) => flags.$get(),
+                               )*
+                               _ => false,
+                       }
+               }
+               #[allow(unused)]
+               fn $set(&mut self) {
+                       match self {
+                               $(
+                                       ChannelState::$state(flags) => flags.$set(),
+                               )*
+                               _ => debug_assert!(false, "Attempted to set flag on unexpected ChannelState"),
+                       }
+               }
+               #[allow(unused)]
+               fn $clear(&mut self) {
+                       match self {
+                               $(
+                                       ChannelState::$state(flags) => { let _ = flags.$clear(); },
+                               )*
+                               _ => debug_assert!(false, "Attempted to clear flag on unexpected ChannelState"),
+                       }
+               }
+       };
+       ($get: ident, $set: ident, $clear: ident, FUNDED_STATES) => {
+               impl_state_flag!($get, $set, $clear, [AwaitingChannelReady, ChannelReady]);
+       };
+       ($get: ident, $set: ident, $clear: ident, $state: ident) => {
+               impl_state_flag!($get, $set, $clear, [$state]);
+       };
+}
+
+impl ChannelState {
+       fn from_u32(state: u32) -> Result<Self, ()> {
+               match state {
+                       state_flags::FUNDING_NEGOTIATED => Ok(ChannelState::FundingNegotiated),
+                       state_flags::SHUTDOWN_COMPLETE => Ok(ChannelState::ShutdownComplete),
+                       val => {
+                               if val & state_flags::AWAITING_CHANNEL_READY == state_flags::AWAITING_CHANNEL_READY {
+                                       AwaitingChannelReadyFlags::from_u32(val & !state_flags::AWAITING_CHANNEL_READY)
+                                               .map(|flags| ChannelState::AwaitingChannelReady(flags))
+                               } else if val & state_flags::CHANNEL_READY == state_flags::CHANNEL_READY {
+                                       ChannelReadyFlags::from_u32(val & !state_flags::CHANNEL_READY)
+                                               .map(|flags| ChannelState::ChannelReady(flags))
+                               } else if let Ok(flags) = NegotiatingFundingFlags::from_u32(val) {
+                                       Ok(ChannelState::NegotiatingFunding(flags))
+                               } else {
+                                       Err(())
+                               }
+                       },
+               }
+       }
+
+       fn to_u32(&self) -> u32 {
+               match self {
+                       ChannelState::NegotiatingFunding(flags) => flags.0,
+                       ChannelState::FundingNegotiated => state_flags::FUNDING_NEGOTIATED,
+                       ChannelState::AwaitingChannelReady(flags) => state_flags::AWAITING_CHANNEL_READY | flags.0,
+                       ChannelState::ChannelReady(flags) => state_flags::CHANNEL_READY | flags.0,
+                       ChannelState::ShutdownComplete => state_flags::SHUTDOWN_COMPLETE,
+               }
+       }
+
+       fn is_pre_funded_state(&self) -> bool {
+               matches!(self, ChannelState::NegotiatingFunding(_)|ChannelState::FundingNegotiated)
+       }
+
+       fn is_both_sides_shutdown(&self) -> bool {
+               self.is_local_shutdown_sent() && self.is_remote_shutdown_sent()
+       }
+
+       fn with_funded_state_flags_mask(&self) -> FundedStateFlags {
+               match self {
+                       ChannelState::AwaitingChannelReady(flags) => FundedStateFlags((*flags & FundedStateFlags::ALL).0),
+                       ChannelState::ChannelReady(flags) => FundedStateFlags((*flags & FundedStateFlags::ALL).0),
+                       _ => FundedStateFlags::new(),
+               }
+       }
+
+       fn can_generate_new_commitment(&self) -> bool {
+               match self {
+                       ChannelState::ChannelReady(flags) =>
+                               !flags.is_set(ChannelReadyFlags::AWAITING_REMOTE_REVOKE) &&
+                                       !flags.is_set(FundedStateFlags::MONITOR_UPDATE_IN_PROGRESS.into()) &&
+                                       !flags.is_set(FundedStateFlags::PEER_DISCONNECTED.into()),
+                       _ => {
+                               debug_assert!(false, "Can only generate new commitment within ChannelReady");
+                               false
+                       },
+               }
+       }
+
+       impl_state_flag!(is_peer_disconnected, set_peer_disconnected, clear_peer_disconnected, FUNDED_STATES);
+       impl_state_flag!(is_monitor_update_in_progress, set_monitor_update_in_progress, clear_monitor_update_in_progress, FUNDED_STATES);
+       impl_state_flag!(is_local_shutdown_sent, set_local_shutdown_sent, clear_local_shutdown_sent, FUNDED_STATES);
+       impl_state_flag!(is_remote_shutdown_sent, set_remote_shutdown_sent, clear_remote_shutdown_sent, FUNDED_STATES);
+       impl_state_flag!(is_our_channel_ready, set_our_channel_ready, clear_our_channel_ready, AwaitingChannelReady);
+       impl_state_flag!(is_their_channel_ready, set_their_channel_ready, clear_their_channel_ready, AwaitingChannelReady);
+       impl_state_flag!(is_waiting_for_batch, set_waiting_for_batch, clear_waiting_for_batch, AwaitingChannelReady);
+       impl_state_flag!(is_awaiting_remote_revoke, set_awaiting_remote_revoke, clear_awaiting_remote_revoke, ChannelReady);
 }
-const BOTH_SIDES_SHUTDOWN_MASK: u32 =
-       ChannelState::LocalShutdownSent as u32 |
-       ChannelState::RemoteShutdownSent as u32;
-const MULTI_STATE_FLAGS: u32 =
-       BOTH_SIDES_SHUTDOWN_MASK |
-       ChannelState::PeerDisconnected as u32 |
-       ChannelState::MonitorUpdateInProgress as u32;
-const STATE_FLAGS: u32 =
-       MULTI_STATE_FLAGS |
-       ChannelState::TheirChannelReady as u32 |
-       ChannelState::OurChannelReady as u32 |
-       ChannelState::AwaitingRemoteRevoke as u32 |
-       ChannelState::WaitingForBatch as u32;
 
 pub const INITIAL_COMMITMENT_NUMBER: u64 = (1 << 48) - 1;
 
@@ -401,6 +661,33 @@ impl fmt::Display for ChannelError {
        }
 }
 
+pub(super) struct WithChannelContext<'a, L: Deref> where L::Target: Logger {
+       pub logger: &'a L,
+       pub peer_id: Option<PublicKey>,
+       pub channel_id: Option<ChannelId>,
+}
+
+impl<'a, L: Deref> Logger for WithChannelContext<'a, L> where L::Target: Logger {
+       fn log(&self, mut record: Record) {
+               record.peer_id = self.peer_id;
+               record.channel_id = self.channel_id;
+               self.logger.log(record)
+       }
+}
+
+impl<'a, 'b, L: Deref> WithChannelContext<'a, L>
+where L::Target: Logger {
+       pub(super) fn from<S: Deref>(logger: &'a L, context: &'b ChannelContext<S>) -> Self
+       where S::Target: SignerProvider
+       {
+               WithChannelContext {
+                       logger,
+                       peer_id: Some(context.counterparty_node_id),
+                       channel_id: Some(context.channel_id),
+               }
+       }
+}
+
 macro_rules! secp_check {
        ($res: expr, $err: expr) => {
                match $res {
@@ -470,9 +757,10 @@ struct CommitmentStats<'a> {
        total_fee_sat: u64, // the total fee included in the transaction
        num_nondust_htlcs: usize,  // the number of HTLC outputs (dust HTLCs *non*-included)
        htlcs_included: Vec<(HTLCOutputInCommitment, Option<&'a HTLCSource>)>, // the list of HTLCs (dust HTLCs *included*) which were not ignored when building the transaction
-       local_balance_msat: u64, // local balance before fees but considering dust limits
-       remote_balance_msat: u64, // remote balance before fees but considering dust limits
-       preimages: Vec<PaymentPreimage>, // preimages for successful offered HTLCs since last commitment
+       local_balance_msat: u64, // local balance before fees *not* considering dust limits
+       remote_balance_msat: u64, // remote balance before fees *not* considering dust limits
+       outbound_htlc_preimages: Vec<PaymentPreimage>, // preimages for successful offered HTLCs since last commitment
+       inbound_htlc_preimages: Vec<PaymentPreimage>, // preimages for successful received HTLCs since last commitment
 }
 
 /// Used when calculating whether we or the remote can afford an additional HTLC.
@@ -530,6 +818,14 @@ pub(super) struct MonitorRestoreUpdates {
        pub announcement_sigs: Option<msgs::AnnouncementSignatures>,
 }
 
+/// The return value of `signer_maybe_unblocked`
+#[allow(unused)]
+pub(super) struct SignerResumeUpdates {
+       pub commitment_update: Option<msgs::CommitmentUpdate>,
+       pub funding_signed: Option<msgs::FundingSigned>,
+       pub channel_ready: Option<msgs::ChannelReady>,
+}
+
 /// The return value of `channel_reestablish`
 pub(super) struct ReestablishResponses {
        pub channel_ready: Option<msgs::ChannelReady>,
@@ -540,18 +836,24 @@ pub(super) struct ReestablishResponses {
        pub shutdown_msg: Option<msgs::Shutdown>,
 }
 
-/// The return type of `force_shutdown`
-///
-/// Contains a tuple with the following:
-/// - An optional (counterparty_node_id, funding_txo, [`ChannelMonitorUpdate`]) tuple
-/// - A list of HTLCs to fail back in the form of the (source, payment hash, and this channel's
-/// counterparty_node_id and channel_id).
-/// - An optional transaction id identifying a corresponding batch funding transaction.
-pub(crate) type ShutdownResult = (
-       Option<(PublicKey, OutPoint, ChannelMonitorUpdate)>,
-       Vec<(HTLCSource, PaymentHash, PublicKey, ChannelId)>,
-       Option<Txid>
-);
+/// The result of a shutdown that should be handled.
+#[must_use]
+pub(crate) struct ShutdownResult {
+       pub(crate) closure_reason: ClosureReason,
+       /// A channel monitor update to apply.
+       pub(crate) monitor_update: Option<(PublicKey, OutPoint, ChannelId, ChannelMonitorUpdate)>,
+       /// A list of dropped outbound HTLCs that can safely be failed backwards immediately.
+       pub(crate) dropped_outbound_htlcs: Vec<(HTLCSource, PaymentHash, PublicKey, ChannelId)>,
+       /// An unbroadcasted batch funding transaction id. The closure of this channel should be
+       /// propagated to the remainder of the batch.
+       pub(crate) unbroadcasted_batch_funding_txid: Option<Txid>,
+       pub(crate) channel_id: ChannelId,
+       pub(crate) user_channel_id: u128,
+       pub(crate) channel_capacity_satoshis: u64,
+       pub(crate) counterparty_node_id: PublicKey,
+       pub(crate) unbroadcasted_funding_tx: Option<Transaction>,
+       pub(crate) channel_funding_txo: Option<OutPoint>,
+}
 
 /// If the majority of the channels funds are to the fundee and the initiator holds only just
 /// enough funds to cover their reserve value, channels are at risk of getting "stuck". Because the
@@ -633,7 +935,7 @@ pub(super) enum ChannelPhase<SP: Deref> where SP::Target: SignerProvider {
 
 impl<'a, SP: Deref> ChannelPhase<SP> where
        SP::Target: SignerProvider,
-       <SP::Target as SignerProvider>::Signer: ChannelSigner,
+       <SP::Target as SignerProvider>::EcdsaSigner: ChannelSigner,
 {
        pub fn context(&'a self) -> &'a ChannelContext<SP> {
                match self {
@@ -692,7 +994,7 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
        /// The temporary channel ID used during channel setup. Value kept even after transitioning to a final channel ID.
        /// Will be `None` for channels created prior to 0.0.115.
        temporary_channel_id: Option<ChannelId>,
-       channel_state: u32,
+       channel_state: ChannelState,
 
        // When we reach max(6 blocks, minimum_depth), we need to send an AnnouncementSigs message to
        // our peer. However, we want to make sure they received it, or else rebroadcast it when we
@@ -711,9 +1013,9 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
 
        latest_monitor_update_id: u64,
 
-       holder_signer: ChannelSignerType<<SP::Target as SignerProvider>::Signer>,
+       holder_signer: ChannelSignerType<SP>,
        shutdown_scriptpubkey: Option<ShutdownScript>,
-       destination_script: Script,
+       destination_script: ScriptBuf,
 
        // Our commitment numbers start at 2^48-1 and count down, whereas the ones used in transaction
        // generation start at 0 and count up...this simplifies some parts of implementation at the
@@ -721,7 +1023,7 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
 
        cur_holder_commitment_transaction_number: u64,
        cur_counterparty_commitment_transaction_number: u64,
-       value_to_self_msat: u64, // Excluding all pending_htlcs, excluding fees
+       value_to_self_msat: u64, // Excluding all pending_htlcs, fees, and anchor outputs
        pending_inbound_htlcs: Vec<InboundHTLCOutput>,
        pending_outbound_htlcs: Vec<OutboundHTLCOutput>,
        holding_cell_htlc_updates: Vec<HTLCUpdateAwaitingACK>,
@@ -747,6 +1049,18 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
        monitor_pending_failures: Vec<(HTLCSource, PaymentHash, HTLCFailReason)>,
        monitor_pending_finalized_fulfills: Vec<HTLCSource>,
 
+       /// If we went to send a commitment update (ie some messages then [`msgs::CommitmentSigned`])
+       /// but our signer (initially) refused to give us a signature, we should retry at some point in
+       /// the future when the signer indicates it may have a signature for us.
+       ///
+       /// This flag is set in such a case. Note that we don't need to persist this as we'll end up
+       /// setting it again as a side-effect of [`Channel::channel_reestablish`].
+       signer_pending_commitment_update: bool,
+       /// Similar to [`Self::signer_pending_commitment_update`] but we're waiting to send either a
+       /// [`msgs::FundingCreated`] or [`msgs::FundingSigned`] depending on if this channel is
+       /// outbound or inbound.
+       signer_pending_funding: bool,
+
        // pending_update_fee is filled when sending and receiving update_fee.
        //
        // Because it follows the same commitment flow as HTLCs, `FeeUpdateState` is either `Outbound`
@@ -792,6 +1106,19 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
        #[cfg(not(test))]
        closing_fee_limits: Option<(u64, u64)>,
 
+       /// If we remove an HTLC (or fee update), commit, and receive our counterparty's
+       /// `revoke_and_ack`, we remove all knowledge of said HTLC (or fee update). However, the latest
+       /// local commitment transaction that we can broadcast still contains the HTLC (or old fee)
+       /// until we receive a further `commitment_signed`. Thus we are not eligible for initiating the
+       /// `closing_signed` negotiation if we're expecting a counterparty `commitment_signed`.
+       ///
+       /// To ensure we don't send a `closing_signed` too early, we track this state here, waiting
+       /// until we see a `commitment_signed` before doing so.
+       ///
+       /// We don't bother to persist this - we anticipate this state won't last longer than a few
+       /// milliseconds, so any accidental force-closes here should be exceedingly rare.
+       expecting_peer_commitment_signed: bool,
+
        /// The hash of the block in which the funding transaction was included.
        funding_tx_confirmed_in: Option<BlockHash>,
        funding_tx_confirmation_height: u32,
@@ -845,7 +1172,7 @@ pub(super) struct ChannelContext<SP: Deref> where SP::Target: SignerProvider {
        counterparty_prev_commitment_point: Option<PublicKey>,
        counterparty_node_id: PublicKey,
 
-       counterparty_shutdown_scriptpubkey: Option<Script>,
+       counterparty_shutdown_scriptpubkey: Option<ScriptBuf>,
 
        commitment_secrets: CounterpartyCommitmentSecrets,
 
@@ -964,49 +1291,55 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
 
        /// Returns true if we've ever received a message from the remote end for this Channel
        pub fn have_received_message(&self) -> bool {
-               self.channel_state & !STATE_FLAGS > (ChannelState::OurInitSent as u32)
+               self.channel_state > ChannelState::NegotiatingFunding(NegotiatingFundingFlags::OUR_INIT_SENT)
        }
 
        /// Returns true if this channel is fully established and not known to be closing.
        /// Allowed in any state (including after shutdown)
        pub fn is_usable(&self) -> bool {
-               let mask = ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK;
-               (self.channel_state & mask) == (ChannelState::ChannelReady as u32) && !self.monitor_pending_channel_ready
+               matches!(self.channel_state, ChannelState::ChannelReady(_)) &&
+                       !self.channel_state.is_local_shutdown_sent() &&
+                       !self.channel_state.is_remote_shutdown_sent() &&
+                       !self.monitor_pending_channel_ready
        }
 
        /// shutdown state returns the state of the channel in its various stages of shutdown
        pub fn shutdown_state(&self) -> ChannelShutdownState {
-               if self.channel_state & (ChannelState::ShutdownComplete as u32) != 0 {
-                       return ChannelShutdownState::ShutdownComplete;
-               }
-               if self.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 &&  self.channel_state & (ChannelState::RemoteShutdownSent as u32) == 0 {
-                       return ChannelShutdownState::ShutdownInitiated;
-               }
-               if (self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0) && !self.closing_negotiation_ready() {
-                       return ChannelShutdownState::ResolvingHTLCs;
-               }
-               if (self.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0) && self.closing_negotiation_ready() {
-                       return ChannelShutdownState::NegotiatingClosingFee;
+               match self.channel_state {
+                       ChannelState::AwaitingChannelReady(_)|ChannelState::ChannelReady(_) =>
+                               if self.channel_state.is_local_shutdown_sent() && !self.channel_state.is_remote_shutdown_sent() {
+                                       ChannelShutdownState::ShutdownInitiated
+                               } else if (self.channel_state.is_local_shutdown_sent() || self.channel_state.is_remote_shutdown_sent()) && !self.closing_negotiation_ready() {
+                                       ChannelShutdownState::ResolvingHTLCs
+                               } else if (self.channel_state.is_local_shutdown_sent() || self.channel_state.is_remote_shutdown_sent()) && self.closing_negotiation_ready() {
+                                       ChannelShutdownState::NegotiatingClosingFee
+                               } else {
+                                       ChannelShutdownState::NotShuttingDown
+                               },
+                       ChannelState::ShutdownComplete => ChannelShutdownState::ShutdownComplete,
+                       _ => ChannelShutdownState::NotShuttingDown,
                }
-               return ChannelShutdownState::NotShuttingDown;
        }
 
        fn closing_negotiation_ready(&self) -> bool {
+               let is_ready_to_close = match self.channel_state {
+                       ChannelState::AwaitingChannelReady(flags) =>
+                               flags & FundedStateFlags::ALL == FundedStateFlags::LOCAL_SHUTDOWN_SENT | FundedStateFlags::REMOTE_SHUTDOWN_SENT,
+                       ChannelState::ChannelReady(flags) =>
+                               flags == FundedStateFlags::LOCAL_SHUTDOWN_SENT | FundedStateFlags::REMOTE_SHUTDOWN_SENT,
+                       _ => false,
+               };
                self.pending_inbound_htlcs.is_empty() &&
-               self.pending_outbound_htlcs.is_empty() &&
-               self.pending_update_fee.is_none() &&
-               self.channel_state &
-               (BOTH_SIDES_SHUTDOWN_MASK |
-                       ChannelState::AwaitingRemoteRevoke as u32 |
-                       ChannelState::PeerDisconnected as u32 |
-                       ChannelState::MonitorUpdateInProgress as u32) == BOTH_SIDES_SHUTDOWN_MASK
+                       self.pending_outbound_htlcs.is_empty() &&
+                       self.pending_update_fee.is_none() &&
+                       is_ready_to_close
        }
 
        /// Returns true if this channel is currently available for use. This is a superset of
        /// is_usable() and considers things like the channel being temporarily disabled.
        /// Allowed in any state (including after shutdown)
        pub fn is_live(&self) -> bool {
-               self.is_usable() && (self.channel_state & (ChannelState::PeerDisconnected as u32) == 0)
+               self.is_usable() && !self.channel_state.is_peer_disconnected()
        }
 
        // Public utilities:
@@ -1054,6 +1387,12 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                self.outbound_scid_alias
        }
 
+       /// Returns the holder signer for this channel.
+       #[cfg(test)]
+       pub fn get_signer(&self) -> &ChannelSignerType<SP> {
+               return &self.holder_signer
+       }
+
        /// Only allowed immediately after deserialization if get_outbound_scid_alias returns 0,
        /// indicating we were written by LDK prior to 0.0.106 which did not set outbound SCID aliases
        /// or prior to any channel actions during `Channel` initialization.
@@ -1068,6 +1407,16 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                self.channel_transaction_parameters.funding_outpoint
        }
 
+       /// Returns the height in which our funding transaction was confirmed.
+       pub fn get_funding_tx_confirmation_height(&self) -> Option<u32> {
+               let conf_height = self.funding_tx_confirmation_height;
+               if conf_height > 0 {
+                       Some(conf_height)
+               } else {
+                       None
+               }
+       }
+
        /// Returns the block hash in which our funding transaction was confirmed.
        pub fn get_funding_tx_confirmed_in(&self) -> Option<BlockHash> {
                self.funding_tx_confirmed_in
@@ -1166,8 +1515,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                match self.config.options.max_dust_htlc_exposure {
                        MaxDustHTLCExposure::FeeRateMultiplier(multiplier) => {
                                let feerate_per_kw = fee_estimator.bounded_sat_per_1000_weight(
-                                       ConfirmationTarget::HighPriority);
-                               feerate_per_kw as u64 * multiplier
+                                       ConfirmationTarget::OnChainSweep) as u64;
+                               feerate_per_kw.saturating_mul(multiplier)
                        },
                        MaxDustHTLCExposure::FixedLimitMsat(limit) => limit,
                }
@@ -1242,8 +1591,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
        /// Returns true if funding_signed was sent/received and the
        /// funding transaction has been broadcast if necessary.
        pub fn is_funding_broadcast(&self) -> bool {
-               self.channel_state & !STATE_FLAGS >= ChannelState::FundingSent as u32 &&
-                       self.channel_state & ChannelState::WaitingForBatch as u32 == 0
+               !self.channel_state.is_pre_funded_state() &&
+                       !matches!(self.channel_state, ChannelState::AwaitingChannelReady(flags) if flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH))
        }
 
        /// Transaction nomenclature is somewhat confusing here as there are many different cases - a
@@ -1337,6 +1686,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        }
                }
 
+               let mut inbound_htlc_preimages: Vec<PaymentPreimage> = Vec::new();
+
                for ref htlc in self.pending_inbound_htlcs.iter() {
                        let (include, state_name) = match htlc.state {
                                InboundHTLCState::RemoteAnnounced(_) => (!generated_by_local, "RemoteAnnounced"),
@@ -1354,7 +1705,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                                match &htlc.state {
                                        &InboundHTLCState::LocalRemoved(ref reason) => {
                                                if generated_by_local {
-                                                       if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
+                                                       if let &InboundHTLCRemovalReason::Fulfill(preimage) = reason {
+                                                               inbound_htlc_preimages.push(preimage);
                                                                value_to_self_msat_offset += htlc.amount_msat as i64;
                                                        }
                                                }
@@ -1364,7 +1716,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        }
                }
 
-               let mut preimages: Vec<PaymentPreimage> = Vec::new();
+
+               let mut outbound_htlc_preimages: Vec<PaymentPreimage> = Vec::new();
 
                for ref htlc in self.pending_outbound_htlcs.iter() {
                        let (include, state_name) = match htlc.state {
@@ -1383,7 +1736,7 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        };
 
                        if let Some(preimage) = preimage_opt {
-                               preimages.push(preimage);
+                               outbound_htlc_preimages.push(preimage);
                        }
 
                        if include {
@@ -1405,13 +1758,13 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        }
                }
 
-               let mut value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
+               let value_to_self_msat: i64 = (self.value_to_self_msat - local_htlc_total_msat) as i64 + value_to_self_msat_offset;
                assert!(value_to_self_msat >= 0);
                // Note that in case they have several just-awaiting-last-RAA fulfills in-progress (ie
                // AwaitingRemoteRevokeToRemove or AwaitingRemovedRemoteRevoke) we may have allowed them to
                // "violate" their reserve value by couting those against it. Thus, we have to convert
                // everything to i64 before subtracting as otherwise we can overflow.
-               let mut value_to_remote_msat: i64 = (self.channel_value_satoshis * 1000) as i64 - (self.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
+               let value_to_remote_msat: i64 = (self.channel_value_satoshis * 1000) as i64 - (self.value_to_self_msat as i64) - (remote_htlc_total_msat as i64) - value_to_self_msat_offset;
                assert!(value_to_remote_msat >= 0);
 
                #[cfg(debug_assertions)]
@@ -1477,10 +1830,6 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                htlcs_included.sort_unstable_by_key(|h| h.0.transaction_output_index.unwrap());
                htlcs_included.append(&mut included_dust_htlcs);
 
-               // For the stats, trimmed-to-0 the value in msats accordingly
-               value_to_self_msat = if (value_to_self_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_self_msat };
-               value_to_remote_msat = if (value_to_remote_msat * 1000) < broadcaster_dust_limit_satoshis as i64 { 0 } else { value_to_remote_msat };
-
                CommitmentStats {
                        tx,
                        feerate_per_kw,
@@ -1489,7 +1838,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        htlcs_included,
                        local_balance_msat: value_to_self_msat as u64,
                        remote_balance_msat: value_to_remote_msat as u64,
-                       preimages
+                       inbound_htlc_preimages,
+                       outbound_htlc_preimages,
                }
        }
 
@@ -1513,8 +1863,6 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
        /// will sign and send to our counterparty.
        /// If an Err is returned, it is a ChannelError::Close (for get_funding_created)
        fn build_remote_transaction_keys(&self) -> TxCreationKeys {
-               //TODO: Ensure that the payment_key derived here ends up in the library users' wallet as we
-               //may see payments to it!
                let revocation_basepoint = &self.get_holder_pubkeys().revocation_basepoint;
                let htlc_basepoint = &self.get_holder_pubkeys().htlc_basepoint;
                let counterparty_pubkeys = self.get_counterparty_pubkeys();
@@ -1525,7 +1873,7 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
        /// 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/InboundV1Channel::new
-       pub fn get_funding_redeemscript(&self) -> Script {
+       pub fn get_funding_redeemscript(&self) -> ScriptBuf {
                make_funding_redeemscript(&self.get_holder_pubkeys().funding_pubkey, self.counterparty_funding_pubkey())
        }
 
@@ -1552,7 +1900,8 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                if let Some(feerate) = outbound_feerate_update {
                        feerate_per_kw = cmp::max(feerate_per_kw, feerate);
                }
-               cmp::max(2530, feerate_per_kw * 1250 / 1000)
+               let feerate_plus_quarter = feerate_per_kw.checked_mul(1250).map(|v| v / 1000);
+               cmp::max(2530, feerate_plus_quarter.unwrap_or(u32::max_value()))
        }
 
        /// Get forwarding information for the counterparty.
@@ -1655,6 +2004,14 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                let inbound_stats = context.get_inbound_pending_htlc_stats(None);
                let outbound_stats = context.get_outbound_pending_htlc_stats(None);
 
+               let mut balance_msat = context.value_to_self_msat;
+               for ref htlc in context.pending_inbound_htlcs.iter() {
+                       if let InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(_)) = htlc.state {
+                               balance_msat += htlc.amount_msat;
+                       }
+               }
+               balance_msat -= outbound_stats.pending_htlcs_value_msat;
+
                let outbound_capacity_msat = context.value_to_self_msat
                                .saturating_sub(outbound_stats.pending_htlcs_value_msat)
                                .saturating_sub(
@@ -1662,6 +2019,11 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
 
                let mut available_capacity_msat = outbound_capacity_msat;
 
+               let anchor_outputs_value_msat = if context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+                       ANCHOR_OUTPUT_VALUE_SATOSHI * 2 * 1000
+               } else {
+                       0
+               };
                if context.is_outbound() {
                        // We should mind channel commit tx fee when computing how much of the available capacity
                        // can be used in the next htlc. Mirrors the logic in send_htlc.
@@ -1676,14 +2038,19 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        }
 
                        let htlc_above_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000, HTLCInitiator::LocalOffered);
-                       let max_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * context.next_local_commit_tx_fee_msat(htlc_above_dust, Some(()));
+                       let mut max_reserved_commit_tx_fee_msat = context.next_local_commit_tx_fee_msat(htlc_above_dust, Some(()));
                        let htlc_dust = HTLCCandidate::new(real_dust_limit_timeout_sat * 1000 - 1, HTLCInitiator::LocalOffered);
-                       let min_reserved_commit_tx_fee_msat = FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE * context.next_local_commit_tx_fee_msat(htlc_dust, Some(()));
+                       let mut min_reserved_commit_tx_fee_msat = context.next_local_commit_tx_fee_msat(htlc_dust, Some(()));
+                       if !context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+                               max_reserved_commit_tx_fee_msat *= FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
+                               min_reserved_commit_tx_fee_msat *= FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
+                       }
 
                        // We will first subtract the fee as if we were above-dust. Then, if the resulting
                        // value ends up being below dust, we have this fee available again. In that case,
                        // match the value to right-below-dust.
-                       let mut capacity_minus_commitment_fee_msat: i64 = (available_capacity_msat as i64) - (max_reserved_commit_tx_fee_msat as i64);
+                       let mut capacity_minus_commitment_fee_msat: i64 = available_capacity_msat as i64 -
+                               max_reserved_commit_tx_fee_msat as i64 - anchor_outputs_value_msat as i64;
                        if capacity_minus_commitment_fee_msat < (real_dust_limit_timeout_sat as i64) * 1000 {
                                let one_htlc_difference_msat = max_reserved_commit_tx_fee_msat - min_reserved_commit_tx_fee_msat;
                                debug_assert!(one_htlc_difference_msat != 0);
@@ -1708,7 +2075,7 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        let remote_balance_msat = (context.channel_value_satoshis * 1000 - context.value_to_self_msat)
                                .saturating_sub(inbound_stats.pending_htlcs_value_msat);
 
-                       if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat {
+                       if remote_balance_msat < max_reserved_commit_tx_fee_msat + holder_selected_chan_reserve_msat + anchor_outputs_value_msat {
                                // If another HTLC's fee would reduce the remote's balance below the reserve limit
                                // we've selected for them, we can only send dust HTLCs.
                                available_capacity_msat = cmp::min(available_capacity_msat, real_dust_limit_success_sat * 1000 - 1);
@@ -1733,14 +2100,14 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                         context.holder_dust_limit_satoshis       + dust_buffer_feerate * htlc_timeout_tx_weight(context.get_channel_type()) / 1000)
                };
                let on_counterparty_dust_htlc_exposure_msat = inbound_stats.on_counterparty_tx_dust_exposure_msat + outbound_stats.on_counterparty_tx_dust_exposure_msat;
-               if on_counterparty_dust_htlc_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat as i64 {
+               if on_counterparty_dust_htlc_exposure_msat as i64 + htlc_success_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
                        remaining_msat_below_dust_exposure_limit =
                                Some(max_dust_htlc_exposure_msat.saturating_sub(on_counterparty_dust_htlc_exposure_msat));
                        dust_exposure_dust_limit_msat = cmp::max(dust_exposure_dust_limit_msat, htlc_success_dust_limit * 1000);
                }
 
                let on_holder_dust_htlc_exposure_msat = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
-               if on_holder_dust_htlc_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat as i64 {
+               if on_holder_dust_htlc_exposure_msat as i64 + htlc_timeout_dust_limit as i64 * 1000 - 1 > max_dust_htlc_exposure_msat.try_into().unwrap_or(i64::max_value()) {
                        remaining_msat_below_dust_exposure_limit = Some(cmp::min(
                                remaining_msat_below_dust_exposure_limit.unwrap_or(u64::max_value()),
                                max_dust_htlc_exposure_msat.saturating_sub(on_holder_dust_htlc_exposure_msat)));
@@ -1771,6 +2138,7 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        outbound_capacity_msat,
                        next_outbound_htlc_limit_msat: available_capacity_msat,
                        next_outbound_htlc_minimum_msat,
+                       balance_msat,
                }
        }
 
@@ -1973,13 +2341,18 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                res
        }
 
-       fn if_unbroadcasted_funding<F, O>(&self, f: F) -> Option<O>
-               where F: Fn() -> Option<O> {
-               if self.channel_state & ChannelState::FundingCreated as u32 != 0 ||
-                  self.channel_state & ChannelState::WaitingForBatch as u32 != 0 {
-                       f()
-               } else {
-                       None
+       fn if_unbroadcasted_funding<F, O>(&self, f: F) -> Option<O> where F: Fn() -> Option<O> {
+               match self.channel_state {
+                       ChannelState::FundingNegotiated => f(),
+                       ChannelState::AwaitingChannelReady(flags) =>
+                               if flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH) ||
+                                       flags.is_set(FundedStateFlags::MONITOR_UPDATE_IN_PROGRESS.into())
+                               {
+                                       f()
+                               } else {
+                                       None
+                               },
+                       _ => None,
                }
        }
 
@@ -2013,12 +2386,12 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
        /// 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 {
+       pub fn force_shutdown(&mut self, should_broadcast: bool, closure_reason: ClosureReason) -> 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);
+               assert!(!matches!(self.channel_state, ChannelState::ShutdownComplete));
 
                // We go ahead and "free" any holding cell HTLCs or HTLCs we haven't yet committed to and
                // return them to fail the payment.
@@ -2033,26 +2406,84 @@ impl<SP: Deref> ChannelContext<SP> where SP::Target: SignerProvider  {
                        }
                }
                let monitor_update = if let Some(funding_txo) = self.get_funding_txo() {
-                       // If we haven't yet exchanged funding signatures (ie channel_state < FundingSent),
+                       // If we haven't yet exchanged funding signatures (ie channel_state < AwaitingChannelReady),
                        // 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 {
+                       if !self.channel_state.is_pre_funded_state() {
                                self.latest_monitor_update_id = CLOSED_CHANNEL_UPDATE_ID;
-                               Some((self.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
+                               Some((self.get_counterparty_node_id(), funding_txo, self.channel_id(), ChannelMonitorUpdate {
                                        update_id: self.latest_monitor_update_id,
+                                       counterparty_node_id: Some(self.counterparty_node_id),
                                        updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
+                                       channel_id: Some(self.channel_id()),
                                }))
                        } else { None }
                } else { None };
                let unbroadcasted_batch_funding_txid = self.unbroadcasted_batch_funding_txid();
+               let unbroadcasted_funding_tx = self.unbroadcasted_funding();
 
-               self.channel_state = ChannelState::ShutdownComplete as u32;
+               self.channel_state = ChannelState::ShutdownComplete;
                self.update_time_counter += 1;
-               (monitor_update, dropped_outbound_htlcs, unbroadcasted_batch_funding_txid)
+               ShutdownResult {
+                       closure_reason,
+                       monitor_update,
+                       dropped_outbound_htlcs,
+                       unbroadcasted_batch_funding_txid,
+                       channel_id: self.channel_id,
+                       user_channel_id: self.user_id,
+                       channel_capacity_satoshis: self.channel_value_satoshis,
+                       counterparty_node_id: self.counterparty_node_id,
+                       unbroadcasted_funding_tx,
+                       channel_funding_txo: self.get_funding_txo(),
+               }
+       }
+
+       /// Only allowed after [`Self::channel_transaction_parameters`] is set.
+       fn get_funding_signed_msg<L: Deref>(&mut self, logger: &L) -> (CommitmentTransaction, Option<msgs::FundingSigned>) where L::Target: Logger {
+               let counterparty_keys = self.build_remote_transaction_keys();
+               let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number + 1, &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 {}",
+                       &self.channel_id(), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
+
+               match &self.holder_signer {
+                       // TODO (arik): move match into calling method for Taproot
+                       ChannelSignerType::Ecdsa(ecdsa) => {
+                               let funding_signed = ecdsa.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), Vec::new(), &self.secp_ctx)
+                                       .map(|(signature, _)| msgs::FundingSigned {
+                                               channel_id: self.channel_id(),
+                                               signature,
+                                               #[cfg(taproot)]
+                                               partial_signature_with_nonce: None,
+                                       })
+                                       .ok();
+
+                               if funding_signed.is_none() {
+                                       #[cfg(not(async_signing))] {
+                                               panic!("Failed to get signature for funding_signed");
+                                       }
+                                       #[cfg(async_signing)] {
+                                               log_trace!(logger, "Counterparty commitment signature not available for funding_signed message; setting signer_pending_funding");
+                                               self.signer_pending_funding = true;
+                                       }
+                               } else if self.signer_pending_funding {
+                                       log_trace!(logger, "Counterparty commitment signature available for funding_signed message; clearing signer_pending_funding");
+                                       self.signer_pending_funding = false;
+                               }
+
+                               // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
+                               (counterparty_initial_commitment_tx, funding_signed)
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
+               }
        }
 }
 
@@ -2107,7 +2538,7 @@ fn commit_tx_fee_sat(feerate_per_kw: u32, num_htlcs: usize, channel_type_feature
 
 // Get the fee cost in MSATS of a commitment tx with a given number of HTLC outputs.
 // Note that num_htlcs should not include dust HTLCs.
-fn commit_tx_fee_msat(feerate_per_kw: u32, num_htlcs: usize, channel_type_features: &ChannelTypeFeatures) -> u64 {
+pub(crate) fn commit_tx_fee_msat(feerate_per_kw: u32, num_htlcs: usize, channel_type_features: &ChannelTypeFeatures) -> u64 {
        // Note that we need to divide before multiplying to round properly,
        // since the lowest denomination of bitcoin on-chain is the satoshi.
        (commitment_tx_base_weight(channel_type_features) + num_htlcs as u64 * COMMITMENT_TX_WEIGHT_PER_HTLC) * feerate_per_kw as u64 / 1000 * 1000
@@ -2128,44 +2559,78 @@ struct CommitmentTxInfoCached {
        feerate: u32,
 }
 
+/// Contents of a wire message that fails an HTLC backwards. Useful for [`Channel::fail_htlc`] to
+/// fail with either [`msgs::UpdateFailMalformedHTLC`] or [`msgs::UpdateFailHTLC`] as needed.
+trait FailHTLCContents {
+       type Message: FailHTLCMessageName;
+       fn to_message(self, htlc_id: u64, channel_id: ChannelId) -> Self::Message;
+       fn to_inbound_htlc_state(self) -> InboundHTLCState;
+       fn to_htlc_update_awaiting_ack(self, htlc_id: u64) -> HTLCUpdateAwaitingACK;
+}
+impl FailHTLCContents for msgs::OnionErrorPacket {
+       type Message = msgs::UpdateFailHTLC;
+       fn to_message(self, htlc_id: u64, channel_id: ChannelId) -> Self::Message {
+               msgs::UpdateFailHTLC { htlc_id, channel_id, reason: self }
+       }
+       fn to_inbound_htlc_state(self) -> InboundHTLCState {
+               InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(self))
+       }
+       fn to_htlc_update_awaiting_ack(self, htlc_id: u64) -> HTLCUpdateAwaitingACK {
+               HTLCUpdateAwaitingACK::FailHTLC { htlc_id, err_packet: self }
+       }
+}
+impl FailHTLCContents for ([u8; 32], u16) {
+       type Message = msgs::UpdateFailMalformedHTLC;
+       fn to_message(self, htlc_id: u64, channel_id: ChannelId) -> Self::Message {
+               msgs::UpdateFailMalformedHTLC {
+                       htlc_id,
+                       channel_id,
+                       sha256_of_onion: self.0,
+                       failure_code: self.1
+               }
+       }
+       fn to_inbound_htlc_state(self) -> InboundHTLCState {
+               InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed(self))
+       }
+       fn to_htlc_update_awaiting_ack(self, htlc_id: u64) -> HTLCUpdateAwaitingACK {
+               HTLCUpdateAwaitingACK::FailMalformedHTLC {
+                       htlc_id,
+                       sha256_of_onion: self.0,
+                       failure_code: self.1
+               }
+       }
+}
+
+trait FailHTLCMessageName {
+       fn name() -> &'static str;
+}
+impl FailHTLCMessageName for msgs::UpdateFailHTLC {
+       fn name() -> &'static str {
+               "update_fail_htlc"
+       }
+}
+impl FailHTLCMessageName for msgs::UpdateFailMalformedHTLC {
+       fn name() -> &'static str {
+               "update_fail_malformed_htlc"
+       }
+}
+
 impl<SP: Deref> Channel<SP> where
        SP::Target: SignerProvider,
-       <SP::Target as SignerProvider>::Signer: WriteableEcdsaChannelSigner
+       <SP::Target as SignerProvider>::EcdsaSigner: WriteableEcdsaChannelSigner
 {
        fn check_remote_fee<F: Deref, L: Deref>(
                channel_type: &ChannelTypeFeatures, fee_estimator: &LowerBoundedFeeEstimator<F>,
                feerate_per_kw: u32, cur_feerate_per_kw: Option<u32>, logger: &L
        ) -> Result<(), ChannelError> where F::Target: FeeEstimator, L::Target: Logger,
        {
-               // We only bound the fee updates on the upper side to prevent completely absurd feerates,
-               // always accepting up to 25 sat/vByte or 10x our fee estimator's "High Priority" fee.
-               // We generally don't care too much if they set the feerate to something very high, but it
-               // could result in the channel being useless due to everything being dust. This doesn't
-               // apply to channels supporting anchor outputs since HTLC transactions are pre-signed with a
-               // zero fee, so their fee is no longer considered to determine dust limits.
-               if !channel_type.supports_anchors_zero_fee_htlc_tx() {
-                       let upper_limit = cmp::max(250 * 25,
-                               fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::HighPriority) as u64 * 10);
-                       if feerate_per_kw as u64 > upper_limit {
-                               return Err(ChannelError::Close(format!("Peer's feerate much too high. Actual: {}. Our expected upper limit: {}", feerate_per_kw, upper_limit)));
-                       }
-               }
-
-               // We can afford to use a lower bound with anchors than previously since we can now bump
-               // fees when broadcasting our commitment. However, we must still make sure we meet the
-               // minimum mempool feerate, until package relay is deployed, such that we can ensure the
-               // commitment transaction propagates throughout node mempools on its own.
                let lower_limit_conf_target = if channel_type.supports_anchors_zero_fee_htlc_tx() {
-                       ConfirmationTarget::MempoolMinimum
+                       ConfirmationTarget::MinAllowedAnchorChannelRemoteFee
                } else {
-                       ConfirmationTarget::Background
+                       ConfirmationTarget::MinAllowedNonAnchorChannelRemoteFee
                };
                let lower_limit = fee_estimator.bounded_sat_per_1000_weight(lower_limit_conf_target);
-               // Some fee estimators round up to the next full sat/vbyte (ie 250 sats per kw), causing
-               // occasional issues with feerate disagreements between an initiator that wants a feerate
-               // of 1.1 sat/vbyte and a receiver that wants 1.1 rounded up to 2. Thus, we always add 250
-               // sat/kw before the comparison here.
-               if feerate_per_kw + 250 < lower_limit {
+               if feerate_per_kw < lower_limit {
                        if let Some(cur_feerate) = cur_feerate_per_kw {
                                if feerate_per_kw > cur_feerate {
                                        log_warn!(logger,
@@ -2174,13 +2639,13 @@ impl<SP: Deref> Channel<SP> where
                                        return Ok(());
                                }
                        }
-                       return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {} (- 250)", feerate_per_kw, lower_limit)));
+                       return Err(ChannelError::Close(format!("Peer's feerate much too low. Actual: {}. Our expected lower limit: {}", feerate_per_kw, lower_limit)));
                }
                Ok(())
        }
 
        #[inline]
-       fn get_closing_scriptpubkey(&self) -> Script {
+       fn get_closing_scriptpubkey(&self) -> ScriptBuf {
                // The shutdown scriptpubkey is set on channel opening when option_upfront_shutdown_script
                // is signaled. Otherwise, it is set when sending a shutdown message. Calling this method
                // outside of those situations will fail.
@@ -2266,7 +2731,7 @@ impl<SP: Deref> Channel<SP> where
        where L::Target: Logger {
                // Assert that we'll add the HTLC claim to the holding cell in `get_update_fulfill_htlc`
                // (see equivalent if condition there).
-               assert!(self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32) != 0);
+               assert!(!self.context.channel_state.can_generate_new_commitment());
                let mon_update_id = self.context.latest_monitor_update_id; // Forget the ChannelMonitor update
                let fulfill_resp = self.get_update_fulfill_htlc(htlc_id_arg, payment_preimage_arg, logger);
                self.context.latest_monitor_update_id = mon_update_id;
@@ -2280,10 +2745,9 @@ impl<SP: Deref> Channel<SP> where
                // caller thought we could have something claimed (cause we wouldn't have accepted in an
                // incoming HTLC anyway). If we got to ShutdownComplete, callers aren't allowed to call us,
                // either.
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        panic!("Was asked to fulfill an HTLC when channel was not in an operational state");
                }
-               assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
 
                // ChannelManager may generate duplicate claims/fails due to HTLC update events from
                // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
@@ -2293,7 +2757,7 @@ impl<SP: Deref> Channel<SP> where
                let mut htlc_value_msat = 0;
                for (idx, htlc) in self.context.pending_inbound_htlcs.iter().enumerate() {
                        if htlc.htlc_id == htlc_id_arg {
-                               debug_assert_eq!(htlc.payment_hash, PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).into_inner()));
+                               debug_assert_eq!(htlc.payment_hash, PaymentHash(Sha256::hash(&payment_preimage_arg.0[..]).to_byte_array()));
                                log_debug!(logger, "Claiming inbound HTLC id {} with payment hash {} with preimage {}",
                                        htlc.htlc_id, htlc.payment_hash, payment_preimage_arg);
                                match htlc.state {
@@ -2331,12 +2795,14 @@ impl<SP: Deref> Channel<SP> where
                self.context.latest_monitor_update_id += 1;
                let monitor_update = ChannelMonitorUpdate {
                        update_id: self.context.latest_monitor_update_id,
+                       counterparty_node_id: Some(self.context.counterparty_node_id),
                        updates: vec![ChannelMonitorUpdateStep::PaymentPreimage {
                                payment_preimage: payment_preimage_arg.clone(),
                        }],
+                       channel_id: Some(self.context.channel_id()),
                };
 
-               if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+               if !self.context.channel_state.can_generate_new_commitment() {
                        // Note that this condition is the same as the assertion in
                        // `claim_htlc_while_disconnected_dropping_mon_update` and must match exactly -
                        // `claim_htlc_while_disconnected_dropping_mon_update` would not work correctly if we
@@ -2352,7 +2818,9 @@ impl<SP: Deref> Channel<SP> where
                                                        return UpdateFulfillFetch::DuplicateClaim {};
                                                }
                                        },
-                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } |
+                                               &HTLCUpdateAwaitingACK::FailMalformedHTLC { htlc_id, .. } =>
+                                       {
                                                if htlc_id_arg == htlc_id {
                                                        log_warn!(logger, "Have preimage and want to fulfill HTLC with pending failure against channel {}", &self.context.channel_id());
                                                        // TODO: We may actually be able to switch to a fulfill here, though its
@@ -2364,7 +2832,7 @@ impl<SP: Deref> Channel<SP> where
                                        _ => {}
                                }
                        }
-                       log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", &self.context.channel_id(), self.context.channel_state);
+                       log_trace!(logger, "Adding HTLC claim to holding_cell in channel {}! Current state: {}", &self.context.channel_id(), self.context.channel_state.to_u32());
                        self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::ClaimHTLC {
                                payment_preimage: payment_preimage_arg, htlc_id: htlc_id_arg,
                        });
@@ -2449,6 +2917,17 @@ impl<SP: Deref> Channel<SP> where
                        .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
        }
 
+       /// Used for failing back with [`msgs::UpdateFailMalformedHTLC`]. For now, this is used when we
+       /// want to fail blinded HTLCs where we are not the intro node.
+       ///
+       /// See [`Self::queue_fail_htlc`] for more info.
+       pub fn queue_fail_malformed_htlc<L: Deref>(
+               &mut self, htlc_id_arg: u64, failure_code: u16, sha256_of_onion: [u8; 32], logger: &L
+       ) -> Result<(), ChannelError> where L::Target: Logger {
+               self.fail_htlc(htlc_id_arg, (sha256_of_onion, failure_code), true, logger)
+                       .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
+       }
+
        /// We can only have one resolution per HTLC. In some cases around reconnect, we may fulfill
        /// an HTLC more than once or fulfill once and then attempt to fail after reconnect. We cannot,
        /// however, fail more than once as we wait for an upstream failure to be irrevocably committed
@@ -2457,12 +2936,13 @@ impl<SP: Deref> Channel<SP> where
        /// If we do fail twice, we `debug_assert!(false)` and return `Ok(None)`. Thus, this will always
        /// return `Ok(_)` if preconditions are met. In any case, `Err`s will only be
        /// [`ChannelError::Ignore`].
-       fn fail_htlc<L: Deref>(&mut self, htlc_id_arg: u64, err_packet: msgs::OnionErrorPacket, mut force_holding_cell: bool, logger: &L)
-       -> Result<Option<msgs::UpdateFailHTLC>, ChannelError> where L::Target: Logger {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+       fn fail_htlc<L: Deref, E: FailHTLCContents + Clone>(
+               &mut self, htlc_id_arg: u64, err_contents: E, mut force_holding_cell: bool,
+               logger: &L
+       ) -> Result<Option<E::Message>, ChannelError> where L::Target: Logger {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        panic!("Was asked to fail an HTLC when channel was not in an operational state");
                }
-               assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
 
                // ChannelManager may generate duplicate claims/fails due to HTLC update events from
                // on-chain ChannelsMonitors during block rescan. Ideally we'd figure out a way to drop
@@ -2496,7 +2976,7 @@ impl<SP: Deref> Channel<SP> where
                        return Ok(None);
                }
 
-               if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+               if !self.context.channel_state.can_generate_new_commitment() {
                        debug_assert!(force_holding_cell, "!force_holding_cell is only called when emptying the holding cell, so we shouldn't end up back in it!");
                        force_holding_cell = true;
                }
@@ -2512,7 +2992,9 @@ impl<SP: Deref> Channel<SP> where
                                                        return Ok(None);
                                                }
                                        },
-                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+                                       &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } |
+                                               &HTLCUpdateAwaitingACK::FailMalformedHTLC { htlc_id, .. } =>
+                                       {
                                                if htlc_id_arg == htlc_id {
                                                        debug_assert!(false, "Tried to fail an HTLC that was already failed");
                                                        return Err(ChannelError::Ignore("Unable to find a pending HTLC which matched the given HTLC ID".to_owned()));
@@ -2522,142 +3004,56 @@ impl<SP: Deref> Channel<SP> where
                                }
                        }
                        log_trace!(logger, "Placing failure for HTLC ID {} in holding cell in channel {}.", htlc_id_arg, &self.context.channel_id());
-                       self.context.holding_cell_htlc_updates.push(HTLCUpdateAwaitingACK::FailHTLC {
-                               htlc_id: htlc_id_arg,
-                               err_packet,
-                       });
+                       self.context.holding_cell_htlc_updates.push(err_contents.to_htlc_update_awaiting_ack(htlc_id_arg));
                        return Ok(None);
                }
 
-               log_trace!(logger, "Failing HTLC ID {} back with a update_fail_htlc message in channel {}.", htlc_id_arg, &self.context.channel_id());
+               log_trace!(logger, "Failing HTLC ID {} back with {} message in channel {}.", htlc_id_arg,
+                       E::Message::name(), &self.context.channel_id());
                {
                        let htlc = &mut self.context.pending_inbound_htlcs[pending_idx];
-                       htlc.state = InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(err_packet.clone()));
+                       htlc.state = err_contents.clone().to_inbound_htlc_state();
                }
 
-               Ok(Some(msgs::UpdateFailHTLC {
-                       channel_id: self.context.channel_id(),
-                       htlc_id: htlc_id_arg,
-                       reason: err_packet
-               }))
+               Ok(Some(err_contents.to_message(htlc_id_arg, self.context.channel_id())))
        }
 
        // Message handlers:
-
-       /// 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<L: Deref>(
-               &mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
-       ) -> Result<ChannelMonitor<<SP::Target as SignerProvider>::Signer>, ChannelError>
-       where
-               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 {}",
-                       &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.as_ref().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_initial_counterparty_commitment_tx(
-                       counterparty_initial_bitcoin_tx.txid, Vec::new(),
-                       self.context.cur_counterparty_commitment_transaction_number,
-                       self.context.counterparty_cur_commitment_point.unwrap(),
-                       counterparty_initial_commitment_tx.feerate_per_kw(),
-                       counterparty_initial_commitment_tx.to_broadcaster_value_sat(),
-                       counterparty_initial_commitment_tx.to_countersignatory_value_sat(), logger);
-
-               assert_eq!(self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32), 0); // We have no had any monitor(s) yet to fail update!
-               if self.context.is_batch_funding() {
-                       self.context.channel_state = ChannelState::FundingSent as u32 | ChannelState::WaitingForBatch as u32;
-               } else {
-                       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 {}", &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)
-       }
-
        /// Updates the state of the channel to indicate that all channels in the batch have received
        /// funding_signed and persisted their monitors.
        /// The funding transaction is consequently allowed to be broadcast, and the channel can be
        /// treated as a non-batch channel going forward.
        pub fn set_batch_ready(&mut self) {
                self.context.is_batch_funding = None;
-               self.context.channel_state &= !(ChannelState::WaitingForBatch as u32);
+               self.context.channel_state.clear_waiting_for_batch();
+       }
+
+       /// Unsets the existing funding information.
+       ///
+       /// This must only be used if the channel has not yet completed funding and has not been used.
+       ///
+       /// Further, the channel must be immediately shut down after this with a call to
+       /// [`ChannelContext::force_shutdown`].
+       pub fn unset_funding_info(&mut self, temporary_channel_id: ChannelId) {
+               debug_assert!(matches!(
+                       self.context.channel_state, ChannelState::AwaitingChannelReady(_)
+               ));
+               self.context.channel_transaction_parameters.funding_outpoint = None;
+               self.context.channel_id = temporary_channel_id;
        }
 
        /// Handles a channel_ready message from our peer. If we've already sent our channel_ready
        /// and the channel is now usable (and public), this may generate an announcement_signatures to
        /// reply with.
        pub fn channel_ready<NS: Deref, L: Deref>(
-               &mut self, msg: &msgs::ChannelReady, node_signer: &NS, genesis_block_hash: BlockHash,
+               &mut self, msg: &msgs::ChannelReady, node_signer: &NS, chain_hash: ChainHash,
                user_config: &UserConfig, best_block: &BestBlock, logger: &L
        ) -> Result<Option<msgs::AnnouncementSignatures>, ChannelError>
        where
                NS::Target: NodeSigner,
                L::Target: Logger
        {
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        self.context.workaround_lnd_bug_4006 = Some(msg.clone());
                        return Err(ChannelError::Ignore("Peer sent channel_ready when we needed a channel_reestablish. The peer is likely lnd, see https://github.com/lightningnetwork/lnd/issues/4006".to_owned()));
                }
@@ -2671,24 +3067,31 @@ impl<SP: Deref> Channel<SP> where
                        }
                }
 
-               let non_shutdown_state = self.context.channel_state & (!MULTI_STATE_FLAGS);
-
                // Our channel_ready shouldn't have been sent if we are waiting for other channels in the
                // batch, but we can receive channel_ready messages.
-               debug_assert!(
-                       non_shutdown_state & ChannelState::OurChannelReady as u32 == 0 ||
-                       non_shutdown_state & ChannelState::WaitingForBatch as u32 == 0
-               );
-               if non_shutdown_state & !(ChannelState::WaitingForBatch as u32) == ChannelState::FundingSent as u32 {
-                       self.context.channel_state |= ChannelState::TheirChannelReady as u32;
-               } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
-                       self.context.channel_state = ChannelState::ChannelReady as u32 | (self.context.channel_state & MULTI_STATE_FLAGS);
-                       self.context.update_time_counter += 1;
-               } else if self.context.channel_state & (ChannelState::ChannelReady as u32) != 0 ||
-                       // If we reconnected before sending our `channel_ready` they may still resend theirs:
-                       (self.context.channel_state & (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) ==
-                                             (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32))
-               {
+               let mut check_reconnection = false;
+               match &self.context.channel_state {
+                       ChannelState::AwaitingChannelReady(flags) => {
+                               let flags = flags.clone().clear(FundedStateFlags::ALL.into());
+                               debug_assert!(!flags.is_set(AwaitingChannelReadyFlags::OUR_CHANNEL_READY) || !flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH));
+                               if flags.clone().clear(AwaitingChannelReadyFlags::WAITING_FOR_BATCH) == AwaitingChannelReadyFlags::THEIR_CHANNEL_READY {
+                                       // If we reconnected before sending our `channel_ready` they may still resend theirs.
+                                       check_reconnection = true;
+                               } else if flags.clone().clear(AwaitingChannelReadyFlags::WAITING_FOR_BATCH).is_empty() {
+                                       self.context.channel_state.set_their_channel_ready();
+                               } else if flags == AwaitingChannelReadyFlags::OUR_CHANNEL_READY {
+                                       self.context.channel_state = ChannelState::ChannelReady(self.context.channel_state.with_funded_state_flags_mask().into());
+                                       self.context.update_time_counter += 1;
+                               } else {
+                                       // We're in `WAITING_FOR_BATCH`, so we should wait until we're ready.
+                                       debug_assert!(flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH));
+                               }
+                       }
+                       // If we reconnected before sending our `channel_ready` they may still resend theirs.
+                       ChannelState::ChannelReady(_) => check_reconnection = true,
+                       _ => return Err(ChannelError::Close("Peer sent a channel_ready at a strange time".to_owned())),
+               }
+               if check_reconnection {
                        // They probably disconnected/reconnected and re-sent the channel_ready, which is
                        // required, or they're sending a fresh SCID alias.
                        let expected_point =
@@ -2712,8 +3115,6 @@ impl<SP: Deref> Channel<SP> where
                                return Err(ChannelError::Close("Peer sent a reconnect channel_ready with a different point".to_owned()));
                        }
                        return Ok(None);
-               } else {
-                       return Err(ChannelError::Close("Peer sent a channel_ready at a strange time".to_owned()));
                }
 
                self.context.counterparty_prev_commitment_point = self.context.counterparty_cur_commitment_point;
@@ -2721,7 +3122,7 @@ impl<SP: Deref> Channel<SP> where
 
                log_info!(logger, "Received channel_ready from peer for channel {}", &self.context.channel_id());
 
-               Ok(self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, best_block.height(), logger))
+               Ok(self.get_announcement_sigs(node_signer, chain_hash, user_config, best_block.height(), logger))
        }
 
        pub fn update_add_htlc<F, FE: Deref, L: Deref>(
@@ -2731,17 +3132,18 @@ impl<SP: Deref> Channel<SP> where
        where F: for<'a> Fn(&'a Self, PendingHTLCStatus, u16) -> PendingHTLCStatus,
                FE::Target: FeeEstimator, L::Target: Logger,
        {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
+                       return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
+               }
                // We can't accept HTLCs sent after we've sent a shutdown.
-               let local_sent_shutdown = (self.context.channel_state & (ChannelState::ChannelReady as u32 | ChannelState::LocalShutdownSent as u32)) != (ChannelState::ChannelReady as u32);
-               if local_sent_shutdown {
+               if self.context.channel_state.is_local_shutdown_sent() {
                        pending_forward_status = create_pending_htlc_status(self, pending_forward_status, 0x4000|8);
                }
                // If the remote has sent a shutdown prior to adding this HTLC, then they are in violation of the spec.
-               let remote_sent_shutdown = (self.context.channel_state & (ChannelState::ChannelReady as u32 | ChannelState::RemoteShutdownSent as u32)) != (ChannelState::ChannelReady as u32);
-               if remote_sent_shutdown {
+               if self.context.channel_state.is_remote_shutdown_sent() {
                        return Err(ChannelError::Close("Got add HTLC message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent update_add_htlc when we needed a channel_reestablish".to_owned()));
                }
                if msg.amount_msat > self.context.channel_value_satoshis * 1000 {
@@ -2762,6 +3164,7 @@ impl<SP: Deref> Channel<SP> where
                if inbound_stats.pending_htlcs_value_msat + msg.amount_msat > self.context.holder_max_htlc_value_in_flight_msat {
                        return Err(ChannelError::Close(format!("Remote HTLC add would put them over our max HTLC value ({})", self.context.holder_max_htlc_value_in_flight_msat)));
                }
+
                // Check holder_selected_channel_reserve_satoshis (we're getting paid, so they have to at least meet
                // the reserve_satoshis we told them to always have as direct payment so that they lose
                // something if we punish them for broadcasting an old state).
@@ -2821,30 +3224,40 @@ impl<SP: Deref> Channel<SP> where
 
                // Check that the remote can afford to pay for this HTLC on-chain at the current
                // feerate_per_kw, while maintaining their channel reserve (as required by the spec).
-               let remote_commit_tx_fee_msat = if self.context.is_outbound() { 0 } else {
-                       let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
-                       self.context.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
-               };
-               if pending_remote_value_msat - msg.amount_msat < remote_commit_tx_fee_msat {
-                       return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
-               };
-
-               if pending_remote_value_msat - msg.amount_msat - remote_commit_tx_fee_msat < self.context.holder_selected_channel_reserve_satoshis * 1000 {
-                       return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
+               {
+                       let remote_commit_tx_fee_msat = if self.context.is_outbound() { 0 } else {
+                               let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
+                               self.context.next_remote_commit_tx_fee_msat(htlc_candidate, None) // Don't include the extra fee spike buffer HTLC in calculations
+                       };
+                       let anchor_outputs_value_msat = if !self.context.is_outbound() && self.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+                               ANCHOR_OUTPUT_VALUE_SATOSHI * 2 * 1000
+                       } else {
+                               0
+                       };
+                       if pending_remote_value_msat.saturating_sub(msg.amount_msat).saturating_sub(anchor_outputs_value_msat) < remote_commit_tx_fee_msat {
+                               return Err(ChannelError::Close("Remote HTLC add would not leave enough to pay for fees".to_owned()));
+                       };
+                       if pending_remote_value_msat.saturating_sub(msg.amount_msat).saturating_sub(remote_commit_tx_fee_msat).saturating_sub(anchor_outputs_value_msat) < self.context.holder_selected_channel_reserve_satoshis * 1000 {
+                               return Err(ChannelError::Close("Remote HTLC add would put them under remote reserve value".to_owned()));
+                       }
                }
 
+               let anchor_outputs_value_msat = if self.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+                       ANCHOR_OUTPUT_VALUE_SATOSHI * 2 * 1000
+               } else {
+                       0
+               };
                if !self.context.is_outbound() {
-                       // `2 *` and `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
-                       // the spec because in the spec, the fee spike buffer requirement doesn't exist on the
-                       // receiver's side, only on the sender's.
-                       // Note that when we eventually remove support for fee updates and switch to anchor output
-                       // fees, we will drop the `2 *`, since we no longer be as sensitive to fee spikes. But, keep
-                       // the extra htlc when calculating the next remote commitment transaction fee as we should
-                       // still be able to afford adding this HTLC plus one more future HTLC, regardless of being
-                       // sensitive to fee spikes.
+                       // `Some(())` is for the fee spike buffer we keep for the remote. This deviates from
+                       // the spec because the fee spike buffer requirement doesn't exist on the receiver's
+                       // side, only on the sender's. Note that with anchor outputs we are no longer as
+                       // sensitive to fee spikes, so we need to account for them.
                        let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
-                       let remote_fee_cost_incl_stuck_buffer_msat = 2 * self.context.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
-                       if pending_remote_value_msat - msg.amount_msat - self.context.holder_selected_channel_reserve_satoshis * 1000 < remote_fee_cost_incl_stuck_buffer_msat {
+                       let mut remote_fee_cost_incl_stuck_buffer_msat = self.context.next_remote_commit_tx_fee_msat(htlc_candidate, Some(()));
+                       if !self.context.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+                               remote_fee_cost_incl_stuck_buffer_msat *= FEE_SPIKE_BUFFER_FEE_INCREASE_MULTIPLE;
+                       }
+                       if pending_remote_value_msat.saturating_sub(msg.amount_msat).saturating_sub(self.context.holder_selected_channel_reserve_satoshis * 1000).saturating_sub(anchor_outputs_value_msat) < remote_fee_cost_incl_stuck_buffer_msat {
                                // Note that if the pending_forward_status is not updated here, then it's because we're already failing
                                // the HTLC, i.e. its status is already set to failing.
                                log_info!(logger, "Attempting to fail HTLC due to fee spike buffer violation in channel {}. Rebalancing is required.", &self.context.channel_id());
@@ -2854,7 +3267,7 @@ impl<SP: Deref> Channel<SP> where
                        // Check that they won't violate our local required channel reserve by adding this HTLC.
                        let htlc_candidate = HTLCCandidate::new(msg.amount_msat, HTLCInitiator::RemoteOffered);
                        let local_commit_tx_fee_msat = self.context.next_local_commit_tx_fee_msat(htlc_candidate, None);
-                       if self.context.value_to_self_msat < self.context.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat {
+                       if self.context.value_to_self_msat < self.context.counterparty_selected_channel_reserve_satoshis.unwrap() * 1000 + local_commit_tx_fee_msat + anchor_outputs_value_msat {
                                return Err(ChannelError::Close("Cannot accept HTLC that would put our balance under counterparty-announced channel reserve value".to_owned()));
                        }
                }
@@ -2865,7 +3278,7 @@ impl<SP: Deref> Channel<SP> where
                        return Err(ChannelError::Close("Remote provided CLTV expiry in seconds instead of block height".to_owned()));
                }
 
-               if self.context.channel_state & ChannelState::LocalShutdownSent as u32 != 0 {
+               if self.context.channel_state.is_local_shutdown_sent() {
                        if let PendingHTLCStatus::Forward(_) = pending_forward_status {
                                panic!("ChannelManager shouldn't be trying to add a forwardable HTLC after we've started closing");
                        }
@@ -2892,7 +3305,7 @@ impl<SP: Deref> Channel<SP> where
                                let outcome = match check_preimage {
                                        None => fail_reason.into(),
                                        Some(payment_preimage) => {
-                                               let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner());
+                                               let payment_hash = PaymentHash(Sha256::hash(&payment_preimage.0[..]).to_byte_array());
                                                if payment_hash != htlc.payment_hash {
                                                        return Err(ChannelError::Close(format!("Remote tried to fulfill HTLC ({}) with an incorrect preimage", htlc_id)));
                                                }
@@ -2914,22 +3327,22 @@ impl<SP: Deref> Channel<SP> where
                Err(ChannelError::Close("Remote tried to fulfill/fail an HTLC we couldn't find".to_owned()))
        }
 
-       pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64), ChannelError> {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+       pub fn update_fulfill_htlc(&mut self, msg: &msgs::UpdateFulfillHTLC) -> Result<(HTLCSource, u64, Option<u64>), ChannelError> {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        return Err(ChannelError::Close("Got fulfill HTLC message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent update_fulfill_htlc when we needed a channel_reestablish".to_owned()));
                }
 
-               self.mark_outbound_htlc_removed(msg.htlc_id, Some(msg.payment_preimage), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat))
+               self.mark_outbound_htlc_removed(msg.htlc_id, Some(msg.payment_preimage), None).map(|htlc| (htlc.source.clone(), htlc.amount_msat, htlc.skimmed_fee_msat))
        }
 
        pub fn update_fail_htlc(&mut self, msg: &msgs::UpdateFailHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        return Err(ChannelError::Close("Got fail HTLC message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent update_fail_htlc when we needed a channel_reestablish".to_owned()));
                }
 
@@ -2938,10 +3351,10 @@ impl<SP: Deref> Channel<SP> where
        }
 
        pub fn update_fail_malformed_htlc(&mut self, msg: &msgs::UpdateFailMalformedHTLC, fail_reason: HTLCFailReason) -> Result<(), ChannelError> {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        return Err(ChannelError::Close("Got fail malformed HTLC message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent update_fail_malformed_htlc when we needed a channel_reestablish".to_owned()));
                }
 
@@ -2952,13 +3365,13 @@ impl<SP: Deref> Channel<SP> where
        pub fn commitment_signed<L: Deref>(&mut self, msg: &msgs::CommitmentSigned, logger: &L) -> Result<Option<ChannelMonitorUpdate>, ChannelError>
                where L::Target: Logger
        {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        return Err(ChannelError::Close("Got commitment signed message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent commitment_signed when we needed a channel_reestablish".to_owned()));
                }
-               if self.context.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.context.last_sent_closing_fee.is_some() {
+               if self.context.channel_state.is_both_sides_shutdown() && self.context.last_sent_closing_fee.is_some() {
                        return Err(ChannelError::Close("Peer sent commitment_signed after we'd started exchanging closing_signeds".to_owned()));
                }
 
@@ -3044,9 +3457,9 @@ impl<SP: Deref> Channel<SP> where
                                let htlc_sighashtype = if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };
                                let htlc_sighash = hash_to_message!(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, htlc_sighashtype).unwrap()[..]);
                                log_trace!(logger, "Checking HTLC tx signature {} by key {} against tx {} (sighash {}) with redeemscript {} in channel {}.",
-                                       log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.serialize()),
+                                       log_bytes!(msg.htlc_signatures[idx].serialize_compact()[..]), log_bytes!(keys.countersignatory_htlc_key.to_public_key().serialize()),
                                        encode::serialize_hex(&htlc_tx), log_bytes!(htlc_sighash[..]), encode::serialize_hex(&htlc_redeemscript), &self.context.channel_id());
-                               if let Err(_) = self.context.secp_ctx.verify_ecdsa(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key) {
+                               if let Err(_) = self.context.secp_ctx.verify_ecdsa(&htlc_sighash, &msg.htlc_signatures[idx], &keys.countersignatory_htlc_key.to_public_key()) {
                                        return Err(ChannelError::Close("Invalid HTLC tx signature from peer".to_owned()));
                                }
                                if !separate_nondust_htlc_sources {
@@ -3071,7 +3484,7 @@ impl<SP: Deref> Channel<SP> where
                        self.context.counterparty_funding_pubkey()
                );
 
-               self.context.holder_signer.as_ref().validate_holder_commitment(&holder_commitment_tx, commitment_stats.preimages)
+               self.context.holder_signer.as_ref().validate_holder_commitment(&holder_commitment_tx, commitment_stats.outbound_htlc_preimages)
                        .map_err(|_| ChannelError::Close("Failed to validate our commitment".to_owned()))?;
 
                // Update state now that we've passed all the can-fail calls...
@@ -3119,27 +3532,30 @@ impl<SP: Deref> Channel<SP> where
                self.context.latest_monitor_update_id += 1;
                let mut monitor_update = ChannelMonitorUpdate {
                        update_id: self.context.latest_monitor_update_id,
+                       counterparty_node_id: Some(self.context.counterparty_node_id),
                        updates: vec![ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo {
                                commitment_tx: holder_commitment_tx,
                                htlc_outputs: htlcs_and_sigs,
                                claimed_htlcs,
                                nondust_htlc_sources,
-                       }]
+                       }],
+                       channel_id: Some(self.context.channel_id()),
                };
 
                self.context.cur_holder_commitment_transaction_number -= 1;
+               self.context.expecting_peer_commitment_signed = false;
                // Note that if we need_commitment & !AwaitingRemoteRevoke we'll call
                // build_commitment_no_status_check() next which will reset this to RAAFirst.
                self.context.resend_order = RAACommitmentOrder::CommitmentFirst;
 
-               if (self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32) != 0 {
+               if self.context.channel_state.is_monitor_update_in_progress() {
                        // In case we initially failed monitor updating without requiring a response, we need
                        // to make sure the RAA gets sent first.
                        self.context.monitor_pending_revoke_and_ack = true;
-                       if need_commitment && (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
+                       if need_commitment && !self.context.channel_state.is_awaiting_remote_revoke() {
                                // If we were going to send a commitment_signed after the RAA, go ahead and do all
-                               // the corresponding HTLC status updates so that get_last_commitment_update
-                               // includes the right HTLCs.
+                               // the corresponding HTLC status updates so that
+                               // get_last_commitment_update_for_send includes the right HTLCs.
                                self.context.monitor_pending_commitment_signed = true;
                                let mut additional_update = self.build_commitment_no_status_check(logger);
                                // build_commitment_no_status_check may bump latest_monitor_id but we want them to be
@@ -3152,7 +3568,7 @@ impl<SP: Deref> Channel<SP> where
                        return Ok(self.push_ret_blockable_mon_update(monitor_update));
                }
 
-               let need_commitment_signed = if need_commitment && (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32)) == 0 {
+               let need_commitment_signed = if need_commitment && !self.context.channel_state.is_awaiting_remote_revoke() {
                        // If we're AwaitingRemoteRevoke we can't send a new commitment here, but that's ok -
                        // we'll send one right away when we get the revoke_and_ack when we
                        // free_holding_cell_htlcs().
@@ -3178,8 +3594,7 @@ impl<SP: Deref> Channel<SP> where
        ) -> (Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>)
        where F::Target: FeeEstimator, L::Target: Logger
        {
-               if self.context.channel_state & !STATE_FLAGS >= ChannelState::ChannelReady as u32 &&
-                  (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) == 0 {
+               if matches!(self.context.channel_state, ChannelState::ChannelReady(_)) && self.context.channel_state.can_generate_new_commitment() {
                        self.free_holding_cell_htlcs(fee_estimator, logger)
                } else { (None, Vec::new()) }
        }
@@ -3191,14 +3606,16 @@ impl<SP: Deref> Channel<SP> where
        ) -> (Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>)
        where F::Target: FeeEstimator, L::Target: Logger
        {
-               assert_eq!(self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32, 0);
+               assert!(!self.context.channel_state.is_monitor_update_in_progress());
                if self.context.holding_cell_htlc_updates.len() != 0 || self.context.holding_cell_update_fee.is_some() {
                        log_trace!(logger, "Freeing holding cell with {} HTLC updates{} in channel {}", self.context.holding_cell_htlc_updates.len(),
                                if self.context.holding_cell_update_fee.is_some() { " and a fee update" } else { "" }, &self.context.channel_id());
 
                        let mut monitor_update = ChannelMonitorUpdate {
                                update_id: self.context.latest_monitor_update_id + 1, // We don't increment this yet!
+                               counterparty_node_id: Some(self.context.counterparty_node_id),
                                updates: Vec::new(),
+                               channel_id: Some(self.context.channel_id()),
                        };
 
                        let mut htlc_updates = Vec::new();
@@ -3213,14 +3630,15 @@ impl<SP: Deref> Channel<SP> where
                                // the limit. In case it's less rare than I anticipate, we may want to revisit
                                // handling this case better and maybe fulfilling some of the HTLCs while attempting
                                // to rebalance channels.
-                               match &htlc_update {
+                               let fail_htlc_res = match &htlc_update {
                                        &HTLCUpdateAwaitingACK::AddHTLC {
                                                amount_msat, cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet,
-                                               skimmed_fee_msat, ..
+                                               skimmed_fee_msat, blinding_point, ..
                                        } => {
-                                               match self.send_htlc(amount_msat, *payment_hash, cltv_expiry, source.clone(),
-                                                       onion_routing_packet.clone(), false, skimmed_fee_msat, fee_estimator, logger)
-                                               {
+                                               match self.send_htlc(
+                                                       amount_msat, *payment_hash, cltv_expiry, source.clone(), onion_routing_packet.clone(),
+                                                       false, skimmed_fee_msat, blinding_point, fee_estimator, logger
+                                               ) {
                                                        Ok(_) => update_add_count += 1,
                                                        Err(e) => {
                                                                match e {
@@ -3240,6 +3658,7 @@ impl<SP: Deref> Channel<SP> where
                                                                }
                                                        }
                                                }
+                                               None
                                        },
                                        &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, htlc_id, .. } => {
                                                // If an HTLC claim was previously added to the holding cell (via
@@ -3253,26 +3672,33 @@ impl<SP: Deref> Channel<SP> where
                                                        { monitor_update } else { unreachable!() };
                                                update_fulfill_count += 1;
                                                monitor_update.updates.append(&mut additional_monitor_update.updates);
+                                               None
                                        },
                                        &HTLCUpdateAwaitingACK::FailHTLC { htlc_id, ref err_packet } => {
-                                               match self.fail_htlc(htlc_id, err_packet.clone(), false, logger) {
-                                                       Ok(update_fail_msg_option) => {
-                                                               // If an HTLC failure was previously added to the holding cell (via
-                                                               // `queue_fail_htlc`) then generating the fail message itself must
-                                                               // not fail - we should never end up in a state where we double-fail
-                                                               // an HTLC or fail-then-claim an HTLC as it indicates we didn't wait
-                                                               // for a full revocation before failing.
-                                                               debug_assert!(update_fail_msg_option.is_some());
-                                                               update_fail_count += 1;
-                                                       },
-                                                       Err(e) => {
-                                                               if let ChannelError::Ignore(_) = e {}
-                                                               else {
-                                                                       panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
-                                                               }
-                                                       }
-                                               }
+                                               Some(self.fail_htlc(htlc_id, err_packet.clone(), false, logger)
+                                                .map(|fail_msg_opt| fail_msg_opt.map(|_| ())))
                                        },
+                                       &HTLCUpdateAwaitingACK::FailMalformedHTLC { htlc_id, failure_code, sha256_of_onion } => {
+                                               Some(self.fail_htlc(htlc_id, (sha256_of_onion, failure_code), false, logger)
+                                                .map(|fail_msg_opt| fail_msg_opt.map(|_| ())))
+                                       }
+                               };
+                               if let Some(res) = fail_htlc_res {
+                                       match res {
+                                               Ok(fail_msg_opt) => {
+                                                       // If an HTLC failure was previously added to the holding cell (via
+                                                       // `queue_fail_{malformed_}htlc`) then generating the fail message itself must
+                                                       // not fail - we should never end up in a state where we double-fail
+                                                       // an HTLC or fail-then-claim an HTLC as it indicates we didn't wait
+                                                       // for a full revocation before failing.
+                                                       debug_assert!(fail_msg_opt.is_some());
+                                                       update_fail_count += 1;
+                                               },
+                                               Err(ChannelError::Ignore(_)) => {},
+                                               Err(_) => {
+                                                       panic!("Got a non-IgnoreError action trying to fail holding cell HTLC");
+                                               },
+                                       }
                                }
                        }
                        if update_add_count == 0 && update_fulfill_count == 0 && update_fail_count == 0 && self.context.holding_cell_update_fee.is_none() {
@@ -3311,13 +3737,13 @@ impl<SP: Deref> Channel<SP> where
        ) -> Result<(Vec<(HTLCSource, PaymentHash)>, Option<ChannelMonitorUpdate>), ChannelError>
        where F::Target: FeeEstimator, L::Target: Logger,
        {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) {
                        return Err(ChannelError::Close("Got revoke/ACK message when channel was not in an operational state".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent revoke_and_ack when we needed a channel_reestablish".to_owned()));
                }
-               if self.context.channel_state & BOTH_SIDES_SHUTDOWN_MASK == BOTH_SIDES_SHUTDOWN_MASK && self.context.last_sent_closing_fee.is_some() {
+               if self.context.channel_state.is_both_sides_shutdown() && self.context.last_sent_closing_fee.is_some() {
                        return Err(ChannelError::Close("Peer sent revoke_and_ack after we'd started exchanging closing_signeds".to_owned()));
                }
 
@@ -3329,7 +3755,7 @@ impl<SP: Deref> Channel<SP> where
                        }
                }
 
-               if self.context.channel_state & ChannelState::AwaitingRemoteRevoke as u32 == 0 {
+               if !self.context.channel_state.is_awaiting_remote_revoke() {
                        // Our counterparty seems to have burned their coins to us (by revoking a state when we
                        // haven't given them a new commitment transaction to broadcast). We should probably
                        // take advantage of this by updating our channel monitor, sending them an error, and
@@ -3352,7 +3778,10 @@ impl<SP: Deref> Channel<SP> where
                                        self.context.cur_counterparty_commitment_transaction_number + 1,
                                        &secret
                                ).map_err(|_| ChannelError::Close("Failed to validate revocation from peer".to_owned()))?;
-                       }
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
                };
 
                self.context.commitment_secrets.provide_secret(self.context.cur_counterparty_commitment_transaction_number + 1, msg.per_commitment_secret)
@@ -3360,17 +3789,19 @@ impl<SP: Deref> Channel<SP> where
                self.context.latest_monitor_update_id += 1;
                let mut monitor_update = ChannelMonitorUpdate {
                        update_id: self.context.latest_monitor_update_id,
+                       counterparty_node_id: Some(self.context.counterparty_node_id),
                        updates: vec![ChannelMonitorUpdateStep::CommitmentSecret {
                                idx: self.context.cur_counterparty_commitment_transaction_number + 1,
                                secret: msg.per_commitment_secret,
                        }],
+                       channel_id: Some(self.context.channel_id()),
                };
 
                // Update state now that we've passed all the can-fail calls...
                // (note that we may still fail to generate the new commitment_signed message, but that's
                // OK, we step the channel here and *then* if the new generation fails we can fail the
                // channel based on that, but stepping stuff here should be safe either way.
-               self.context.channel_state &= !(ChannelState::AwaitingRemoteRevoke as u32);
+               self.context.channel_state.clear_awaiting_remote_revoke();
                self.context.sent_message_awaiting_response = None;
                self.context.counterparty_prev_commitment_point = self.context.counterparty_cur_commitment_point;
                self.context.counterparty_cur_commitment_point = Some(msg.next_per_commitment_point);
@@ -3393,6 +3824,7 @@ impl<SP: Deref> Channel<SP> where
                        // Take references explicitly so that we can hold multiple references to self.context.
                        let pending_inbound_htlcs: &mut Vec<_> = &mut self.context.pending_inbound_htlcs;
                        let pending_outbound_htlcs: &mut Vec<_> = &mut self.context.pending_outbound_htlcs;
+                       let expecting_peer_commitment_signed = &mut self.context.expecting_peer_commitment_signed;
 
                        // We really shouldnt have two passes here, but retain gives a non-mutable ref (Rust bug)
                        pending_inbound_htlcs.retain(|htlc| {
@@ -3401,6 +3833,7 @@ impl<SP: Deref> Channel<SP> where
                                        if let &InboundHTLCRemovalReason::Fulfill(_) = reason {
                                                value_to_self_msat_diff += htlc.amount_msat as i64;
                                        }
+                                       *expecting_peer_commitment_signed = true;
                                        false
                                } else { true }
                        });
@@ -3460,6 +3893,7 @@ impl<SP: Deref> Channel<SP> where
                                if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
                                        log_trace!(logger, " ...promoting outbound LocalAnnounced {} to Committed", &htlc.payment_hash);
                                        htlc.state = OutboundHTLCState::Committed;
+                                       *expecting_peer_commitment_signed = true;
                                }
                                if let &mut OutboundHTLCState::AwaitingRemoteRevokeToRemove(ref mut outcome) = &mut htlc.state {
                                        log_trace!(logger, " ...promoting outbound AwaitingRemoteRevokeToRemove {} to AwaitingRemovedRemoteRevoke", &htlc.payment_hash);
@@ -3480,6 +3914,7 @@ impl<SP: Deref> Channel<SP> where
                                        log_trace!(logger, " ...promoting outbound fee update {} to Committed", feerate);
                                        self.context.feerate_per_kw = feerate;
                                        self.context.pending_update_fee = None;
+                                       self.context.expecting_peer_commitment_signed = true;
                                },
                                FeeUpdateState::RemoteAnnounced => { debug_assert!(!self.context.is_outbound()); },
                                FeeUpdateState::AwaitingRemoteRevokeToAnnounce => {
@@ -3508,14 +3943,15 @@ impl<SP: Deref> Channel<SP> where
                        }
                }
 
-               if (self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32) == ChannelState::MonitorUpdateInProgress as u32 {
+               if self.context.channel_state.is_monitor_update_in_progress() {
                        // We can't actually generate a new commitment transaction (incl by freeing holding
                        // cells) while we can't update the monitor, so we just return what we have.
                        if require_commitment {
                                self.context.monitor_pending_commitment_signed = true;
-                               // When the monitor updating is restored we'll call get_last_commitment_update(),
-                               // which does not update state, but we're definitely now awaiting a remote revoke
-                               // before we can step forward any more, so set it here.
+                               // When the monitor updating is restored we'll call
+                               // get_last_commitment_update_for_send(), which does not update state, but we're
+                               // definitely now awaiting a remote revoke before we can step forward any more, so
+                               // set it here.
                                let mut additional_update = self.build_commitment_no_status_check(logger);
                                // build_commitment_no_status_check may bump latest_monitor_id but we want them to be
                                // strictly increasing by one, so decrement it here.
@@ -3629,7 +4065,7 @@ impl<SP: Deref> Channel<SP> where
                        return None;
                }
 
-               if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
+               if self.context.channel_state.is_awaiting_remote_revoke() || self.context.channel_state.is_monitor_update_in_progress() {
                        force_holding_cell = true;
                }
 
@@ -3654,12 +4090,12 @@ impl<SP: Deref> Channel<SP> where
        /// completed.
        /// May return `Err(())`, which implies [`ChannelContext::force_shutdown`] should be called immediately.
        pub fn remove_uncommitted_htlcs_and_mark_paused<L: Deref>(&mut self, logger: &L) -> Result<(), ()> where L::Target: Logger {
-               assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
-               if self.context.channel_state & !STATE_FLAGS < ChannelState::FundingSent as u32 {
-                       return Err(());
+               assert!(!matches!(self.context.channel_state, ChannelState::ShutdownComplete));
+               if self.context.channel_state.is_pre_funded_state() {
+                       return Err(())
                }
 
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == (ChannelState::PeerDisconnected as u32) {
+               if self.context.channel_state.is_peer_disconnected() {
                        // While the below code should be idempotent, it's simpler to just return early, as
                        // redundant disconnect events can fire, though they should be rare.
                        return Ok(());
@@ -3721,7 +4157,7 @@ impl<SP: Deref> Channel<SP> where
 
                self.context.sent_message_awaiting_response = None;
 
-               self.context.channel_state |= ChannelState::PeerDisconnected as u32;
+               self.context.channel_state.set_peer_disconnected();
                log_trace!(logger, "Peer disconnection resulted in {} remote-announced HTLC drops on channel {}", inbound_drop_count, &self.context.channel_id());
                Ok(())
        }
@@ -3748,33 +4184,36 @@ impl<SP: Deref> Channel<SP> where
                self.context.monitor_pending_forwards.append(&mut pending_forwards);
                self.context.monitor_pending_failures.append(&mut pending_fails);
                self.context.monitor_pending_finalized_fulfills.append(&mut pending_finalized_claimed_htlcs);
-               self.context.channel_state |= ChannelState::MonitorUpdateInProgress as u32;
+               self.context.channel_state.set_monitor_update_in_progress();
        }
 
        /// Indicates that the latest ChannelMonitor update has been committed by the client
        /// successfully and we should restore normal operation. Returns messages which should be sent
        /// to the remote side.
        pub fn monitor_updating_restored<L: Deref, NS: Deref>(
-               &mut self, logger: &L, node_signer: &NS, genesis_block_hash: BlockHash,
+               &mut self, logger: &L, node_signer: &NS, chain_hash: ChainHash,
                user_config: &UserConfig, best_block_height: u32
        ) -> MonitorRestoreUpdates
        where
                L::Target: Logger,
                NS::Target: NodeSigner
        {
-               assert_eq!(self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32, ChannelState::MonitorUpdateInProgress as u32);
-               self.context.channel_state &= !(ChannelState::MonitorUpdateInProgress as u32);
+               assert!(self.context.channel_state.is_monitor_update_in_progress());
+               self.context.channel_state.clear_monitor_update_in_progress();
 
-               // If we're past (or at) the FundingSent stage on an outbound channel, try to
+               // If we're past (or at) the AwaitingChannelReady stage on an outbound channel, try to
                // (re-)broadcast the funding transaction as we may have declined to broadcast it when we
                // first received the funding_signed.
                let mut funding_broadcastable =
-                       if self.context.is_outbound() && self.context.channel_state & !STATE_FLAGS >= ChannelState::FundingSent as u32 && self.context.channel_state & ChannelState::WaitingForBatch as u32 == 0 {
+                       if self.context.is_outbound() &&
+                               (matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(flags) if !flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH)) ||
+                               matches!(self.context.channel_state, ChannelState::ChannelReady(_)))
+                       {
                                self.context.funding_transaction.take()
                        } else { None };
                // That said, if the funding transaction is already confirmed (ie we're active with a
                // minimum_depth over 0) don't bother re-broadcasting the confirmed funding tx.
-               if self.context.channel_state & !STATE_FLAGS >= ChannelState::ChannelReady as u32 && self.context.minimum_depth != Some(0) {
+               if matches!(self.context.channel_state, ChannelState::ChannelReady(_)) && self.context.minimum_depth != Some(0) {
                        funding_broadcastable = None;
                }
 
@@ -3796,7 +4235,7 @@ impl<SP: Deref> Channel<SP> where
                        })
                } else { None };
 
-               let announcement_sigs = self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, best_block_height, logger);
+               let announcement_sigs = self.get_announcement_sigs(node_signer, chain_hash, user_config, best_block_height, logger);
 
                let mut accepted_htlcs = Vec::new();
                mem::swap(&mut accepted_htlcs, &mut self.context.monitor_pending_forwards);
@@ -3805,7 +4244,7 @@ impl<SP: Deref> Channel<SP> where
                let mut finalized_claimed_htlcs = Vec::new();
                mem::swap(&mut finalized_claimed_htlcs, &mut self.context.monitor_pending_finalized_fulfills);
 
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) != 0 {
+               if self.context.channel_state.is_peer_disconnected() {
                        self.context.monitor_pending_revoke_and_ack = false;
                        self.context.monitor_pending_commitment_signed = false;
                        return MonitorRestoreUpdates {
@@ -3818,9 +4257,11 @@ impl<SP: Deref> Channel<SP> where
                        Some(self.get_last_revoke_and_ack())
                } else { None };
                let commitment_update = if self.context.monitor_pending_commitment_signed {
-                       self.mark_awaiting_response();
-                       Some(self.get_last_commitment_update(logger))
+                       self.get_last_commitment_update_for_send(logger).ok()
                } else { None };
+               if commitment_update.is_some() {
+                       self.mark_awaiting_response();
+               }
 
                self.context.monitor_pending_revoke_and_ack = false;
                self.context.monitor_pending_commitment_signed = false;
@@ -3840,18 +4281,15 @@ impl<SP: Deref> Channel<SP> where
                if self.context.is_outbound() {
                        return Err(ChannelError::Close("Non-funding remote tried to update channel fee".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent update_fee when we needed a channel_reestablish".to_owned()));
                }
                Channel::<SP>::check_remote_fee(&self.context.channel_type, fee_estimator, msg.feerate_per_kw, Some(self.context.feerate_per_kw), logger)?;
-               let feerate_over_dust_buffer = msg.feerate_per_kw > self.context.get_dust_buffer_feerate(None);
 
                self.context.pending_update_fee = Some((msg.feerate_per_kw, FeeUpdateState::RemoteAnnounced));
                self.context.update_time_counter += 1;
-               // If the feerate has increased over the previous dust buffer (note that
-               // `get_dust_buffer_feerate` considers the `pending_update_fee` status), check that we
-               // won't be pushed over our dust exposure limit by the feerate increase.
-               if feerate_over_dust_buffer {
+               // Check that we won't be pushed over our dust exposure limit by the feerate increase.
+               if !self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
                        let inbound_stats = self.context.get_inbound_pending_htlc_stats(None);
                        let outbound_stats = self.context.get_outbound_pending_htlc_stats(None);
                        let holder_tx_dust_exposure = inbound_stats.on_holder_tx_dust_exposure_msat + outbound_stats.on_holder_tx_dust_exposure_msat;
@@ -3869,6 +4307,32 @@ impl<SP: Deref> Channel<SP> where
                Ok(())
        }
 
+       /// Indicates that the signer may have some signatures for us, so we should retry if we're
+       /// blocked.
+       #[cfg(async_signing)]
+       pub fn signer_maybe_unblocked<L: Deref>(&mut self, logger: &L) -> SignerResumeUpdates where L::Target: Logger {
+               let commitment_update = if self.context.signer_pending_commitment_update {
+                       self.get_last_commitment_update_for_send(logger).ok()
+               } else { None };
+               let funding_signed = if self.context.signer_pending_funding && !self.context.is_outbound() {
+                       self.context.get_funding_signed_msg(logger).1
+               } else { None };
+               let channel_ready = if funding_signed.is_some() {
+                       self.check_get_channel_ready(0)
+               } else { None };
+
+               log_trace!(logger, "Signer unblocked with {} commitment_update, {} funding_signed and {} channel_ready",
+                       if commitment_update.is_some() { "a" } else { "no" },
+                       if funding_signed.is_some() { "a" } else { "no" },
+                       if channel_ready.is_some() { "a" } else { "no" });
+
+               SignerResumeUpdates {
+                       commitment_update,
+                       funding_signed,
+                       channel_ready,
+               }
+       }
+
        fn get_last_revoke_and_ack(&self) -> msgs::RevokeAndACK {
                let next_per_commitment_point = self.context.holder_signer.as_ref().get_per_commitment_point(self.context.cur_holder_commitment_transaction_number, &self.context.secp_ctx);
                let per_commitment_secret = self.context.holder_signer.as_ref().release_commitment_secret(self.context.cur_holder_commitment_transaction_number + 2);
@@ -3881,7 +4345,8 @@ impl<SP: Deref> Channel<SP> where
                }
        }
 
-       fn get_last_commitment_update<L: Deref>(&self, logger: &L) -> msgs::CommitmentUpdate where L::Target: Logger {
+       /// Gets the last commitment update for immediate sending to our peer.
+       fn get_last_commitment_update_for_send<L: Deref>(&mut self, logger: &L) -> Result<msgs::CommitmentUpdate, ()> where L::Target: Logger {
                let mut update_add_htlcs = Vec::new();
                let mut update_fulfill_htlcs = Vec::new();
                let mut update_fail_htlcs = Vec::new();
@@ -3897,6 +4362,7 @@ impl<SP: Deref> Channel<SP> where
                                        cltv_expiry: htlc.cltv_expiry,
                                        onion_routing_packet: (**onion_packet).clone(),
                                        skimmed_fee_msat: htlc.skimmed_fee_msat,
+                                       blinding_point: htlc.blinding_point,
                                });
                        }
                }
@@ -3937,18 +4403,36 @@ impl<SP: Deref> Channel<SP> where
                        })
                } else { None };
 
-               log_trace!(logger, "Regenerated latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
+               log_trace!(logger, "Regenerating latest commitment update in channel {} with{} {} update_adds, {} update_fulfills, {} update_fails, and {} update_fail_malformeds",
                                &self.context.channel_id(), if update_fee.is_some() { " update_fee," } else { "" },
                                update_add_htlcs.len(), update_fulfill_htlcs.len(), update_fail_htlcs.len(), update_fail_malformed_htlcs.len());
-               msgs::CommitmentUpdate {
+               let commitment_signed = if let Ok(update) = self.send_commitment_no_state_update(logger).map(|(cu, _)| cu) {
+                       if self.context.signer_pending_commitment_update {
+                               log_trace!(logger, "Commitment update generated: clearing signer_pending_commitment_update");
+                               self.context.signer_pending_commitment_update = false;
+                       }
+                       update
+               } else {
+                       #[cfg(not(async_signing))] {
+                               panic!("Failed to get signature for new commitment state");
+                       }
+                       #[cfg(async_signing)] {
+                               if !self.context.signer_pending_commitment_update {
+                                       log_trace!(logger, "Commitment update awaiting signer: setting signer_pending_commitment_update");
+                                       self.context.signer_pending_commitment_update = true;
+                               }
+                               return Err(());
+                       }
+               };
+               Ok(msgs::CommitmentUpdate {
                        update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
-                       commitment_signed: self.send_commitment_no_state_update(logger).expect("It looks like we failed to re-generate a commitment_signed we had previously sent?").0,
-               }
+                       commitment_signed,
+               })
        }
 
        /// Gets the `Shutdown` message we should send our peer on reconnect, if any.
        pub fn get_outbound_shutdown(&self) -> Option<msgs::Shutdown> {
-               if self.context.channel_state & (ChannelState::LocalShutdownSent as u32) != 0 {
+               if self.context.channel_state.is_local_shutdown_sent() {
                        assert!(self.context.shutdown_scriptpubkey.is_some());
                        Some(msgs::Shutdown {
                                channel_id: self.context.channel_id,
@@ -3966,13 +4450,13 @@ impl<SP: Deref> Channel<SP> where
        /// [`super::channelmanager::ChannelManager::force_close_all_channels_without_broadcasting_txn`].
        pub fn channel_reestablish<L: Deref, NS: Deref>(
                &mut self, msg: &msgs::ChannelReestablish, logger: &L, node_signer: &NS,
-               genesis_block_hash: BlockHash, user_config: &UserConfig, best_block: &BestBlock
+               chain_hash: ChainHash, user_config: &UserConfig, best_block: &BestBlock
        ) -> Result<ReestablishResponses, ChannelError>
        where
                L::Target: Logger,
                NS::Target: NodeSigner
        {
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
+               if !self.context.channel_state.is_peer_disconnected() {
                        // While BOLT 2 doesn't indicate explicitly we should error this channel here, it
                        // almost certainly indicates we are going to end up out-of-sync in some way, so we
                        // just close here instead of trying to recover.
@@ -3981,9 +4465,10 @@ impl<SP: Deref> Channel<SP> where
 
                if msg.next_local_commitment_number >= INITIAL_COMMITMENT_NUMBER || msg.next_remote_commitment_number >= INITIAL_COMMITMENT_NUMBER ||
                        msg.next_local_commitment_number == 0 {
-                       return Err(ChannelError::Close("Peer sent a garbage channel_reestablish (usually an lnd node with lost state asking us to force-close for them)".to_owned()));
+                       return Err(ChannelError::Close("Peer sent an invalid channel_reestablish to force close in a non-standard way".to_owned()));
                }
 
+               let our_commitment_transaction = INITIAL_COMMITMENT_NUMBER - self.context.cur_holder_commitment_transaction_number - 1;
                if msg.next_remote_commitment_number > 0 {
                        let expected_point = self.context.holder_signer.as_ref().get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - msg.next_remote_commitment_number + 1, &self.context.secp_ctx);
                        let given_secret = SecretKey::from_slice(&msg.your_last_per_commitment_secret)
@@ -3991,7 +4476,7 @@ impl<SP: Deref> Channel<SP> where
                        if expected_point != PublicKey::from_secret_key(&self.context.secp_ctx, &given_secret) {
                                return Err(ChannelError::Close("Peer sent a garbage channel_reestablish with secret key not matching the commitment height provided".to_owned()));
                        }
-                       if msg.next_remote_commitment_number > INITIAL_COMMITMENT_NUMBER - self.context.cur_holder_commitment_transaction_number {
+                       if msg.next_remote_commitment_number > our_commitment_transaction {
                                macro_rules! log_and_panic {
                                        ($err_msg: expr) => {
                                                log_error!(logger, $err_msg, &self.context.channel_id, log_pubkey!(self.context.counterparty_node_id));
@@ -4011,26 +4496,27 @@ impl<SP: Deref> Channel<SP> where
 
                // Before we change the state of the channel, we check if the peer is sending a very old
                // commitment transaction number, if yes we send a warning message.
-               let our_commitment_transaction = INITIAL_COMMITMENT_NUMBER - self.context.cur_holder_commitment_transaction_number - 1;
-               if  msg.next_remote_commitment_number + 1 < our_commitment_transaction {
-                       return Err(
-                               ChannelError::Warn(format!("Peer attempted to reestablish channel with a very old local commitment transaction: {} (received) vs {} (expected)", msg.next_remote_commitment_number, our_commitment_transaction))
-                       );
+               if msg.next_remote_commitment_number + 1 < our_commitment_transaction {
+                       return Err(ChannelError::Warn(format!(
+                               "Peer attempted to reestablish channel with a very old local commitment transaction: {} (received) vs {} (expected)",
+                               msg.next_remote_commitment_number,
+                               our_commitment_transaction
+                       )));
                }
 
                // Go ahead and unmark PeerDisconnected as various calls we may make check for it (and all
                // remaining cases either succeed or ErrorMessage-fail).
-               self.context.channel_state &= !(ChannelState::PeerDisconnected as u32);
+               self.context.channel_state.clear_peer_disconnected();
                self.context.sent_message_awaiting_response = None;
 
                let shutdown_msg = self.get_outbound_shutdown();
 
-               let announcement_sigs = self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, best_block.height(), logger);
+               let announcement_sigs = self.get_announcement_sigs(node_signer, chain_hash, user_config, best_block.height(), logger);
 
-               if self.context.channel_state & (ChannelState::FundingSent as u32) == ChannelState::FundingSent as u32 {
+               if matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(_)) {
                        // If we're waiting on a monitor update, we shouldn't re-send any channel_ready's.
-                       if self.context.channel_state & (ChannelState::OurChannelReady as u32) == 0 ||
-                                       self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32) != 0 {
+                       if !self.context.channel_state.is_our_channel_ready() ||
+                                       self.context.channel_state.is_monitor_update_in_progress() {
                                if msg.next_remote_commitment_number != 0 {
                                        return Err(ChannelError::Close("Peer claimed they saw a revoke_and_ack but we haven't sent channel_ready yet".to_owned()));
                                }
@@ -4057,26 +4543,31 @@ impl<SP: Deref> Channel<SP> where
                        });
                }
 
-               let required_revoke = if msg.next_remote_commitment_number + 1 == INITIAL_COMMITMENT_NUMBER - self.context.cur_holder_commitment_transaction_number {
+               let required_revoke = if msg.next_remote_commitment_number == our_commitment_transaction {
                        // Remote isn't waiting on any RevokeAndACK from us!
                        // Note that if we need to repeat our ChannelReady we'll do that in the next if block.
                        None
-               } else if msg.next_remote_commitment_number + 1 == (INITIAL_COMMITMENT_NUMBER - 1) - self.context.cur_holder_commitment_transaction_number {
-                       if self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32) != 0 {
+               } else if msg.next_remote_commitment_number + 1 == our_commitment_transaction {
+                       if self.context.channel_state.is_monitor_update_in_progress() {
                                self.context.monitor_pending_revoke_and_ack = true;
                                None
                        } else {
                                Some(self.get_last_revoke_and_ack())
                        }
                } else {
-                       return Err(ChannelError::Close("Peer attempted to reestablish channel with a very old local commitment transaction".to_owned()));
+                       debug_assert!(false, "All values should have been handled in the four cases above");
+                       return Err(ChannelError::Close(format!(
+                               "Peer attempted to reestablish channel expecting a future local commitment transaction: {} (received) vs {} (expected)",
+                               msg.next_remote_commitment_number,
+                               our_commitment_transaction
+                       )));
                };
 
                // We increment cur_counterparty_commitment_transaction_number only upon receipt of
                // revoke_and_ack, not on sending commitment_signed, so we add one if have
                // AwaitingRemoteRevoke set, which indicates we sent a commitment_signed but haven't gotten
                // the corresponding revoke_and_ack back yet.
-               let is_awaiting_remote_revoke = self.context.channel_state & ChannelState::AwaitingRemoteRevoke as u32 != 0;
+               let is_awaiting_remote_revoke = self.context.channel_state.is_awaiting_remote_revoke();
                if is_awaiting_remote_revoke && !self.is_awaiting_monitor_update() {
                        self.mark_awaiting_response();
                }
@@ -4112,7 +4603,7 @@ impl<SP: Deref> Channel<SP> where
                                log_debug!(logger, "Reconnected channel {} with only lost remote commitment tx", &self.context.channel_id());
                        }
 
-                       if self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32) != 0 {
+                       if self.context.channel_state.is_monitor_update_in_progress() {
                                self.context.monitor_pending_commitment_signed = true;
                                Ok(ReestablishResponses {
                                        channel_ready, shutdown_msg, announcement_sigs,
@@ -4123,12 +4614,22 @@ impl<SP: Deref> Channel<SP> where
                                Ok(ReestablishResponses {
                                        channel_ready, shutdown_msg, announcement_sigs,
                                        raa: required_revoke,
-                                       commitment_update: Some(self.get_last_commitment_update(logger)),
+                                       commitment_update: self.get_last_commitment_update_for_send(logger).ok(),
                                        order: self.context.resend_order.clone(),
                                })
                        }
+               } else if msg.next_local_commitment_number < next_counterparty_commitment_number {
+                       Err(ChannelError::Close(format!(
+                               "Peer attempted to reestablish channel with a very old remote commitment transaction: {} (received) vs {} (expected)",
+                               msg.next_local_commitment_number,
+                               next_counterparty_commitment_number,
+                       )))
                } else {
-                       Err(ChannelError::Close("Peer attempted to reestablish channel with a very old remote commitment transaction".to_owned()))
+                       Err(ChannelError::Close(format!(
+                               "Peer attempted to reestablish channel with a future remote commitment transaction: {} (received) vs {} (expected)",
+                               msg.next_local_commitment_number,
+                               next_counterparty_commitment_number,
+                       )))
                }
        }
 
@@ -4144,8 +4645,10 @@ impl<SP: Deref> Channel<SP> where
                // Propose a range from our current Background feerate to our Normal feerate plus our
                // force_close_avoidance_max_fee_satoshis.
                // If we fail to come to consensus, we'll have to force-close.
-               let mut proposed_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Background);
-               let normal_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
+               let mut proposed_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::ChannelCloseMinimum);
+               // Use NonAnchorChannelFee because this should be an estimate for a channel close
+               // that we don't expect to need fee bumping
+               let normal_feerate = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::NonAnchorChannelFee);
                let mut proposed_max_feerate = if self.context.is_outbound() { normal_feerate } else { u32::max_value() };
 
                // The spec requires that (when the channel does not have anchors) we only send absolute
@@ -4207,18 +4710,28 @@ impl<SP: Deref> Channel<SP> where
 
        pub fn maybe_propose_closing_signed<F: Deref, L: Deref>(
                &mut self, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
-               -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
+               -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>, Option<ShutdownResult>), ChannelError>
                where F::Target: FeeEstimator, L::Target: Logger
        {
+               // If we're waiting on a monitor persistence, that implies we're also waiting to send some
+               // message to our counterparty (probably a `revoke_and_ack`). In such a case, we shouldn't
+               // initiate `closing_signed` negotiation until we're clear of all pending messages. Note
+               // that closing_negotiation_ready checks this case (as well as a few others).
                if self.context.last_sent_closing_fee.is_some() || !self.closing_negotiation_ready() {
-                       return Ok((None, None));
+                       return Ok((None, None, None));
                }
 
                if !self.context.is_outbound() {
                        if let Some(msg) = &self.context.pending_counterparty_closing_signed.take() {
                                return self.closing_signed(fee_estimator, &msg);
                        }
-                       return Ok((None, None));
+                       return Ok((None, None, None));
+               }
+
+               // If we're waiting on a counterparty `commitment_signed` to clear some updates from our
+               // local commitment transaction, we can't yet initiate `closing_signed` negotiation.
+               if self.context.expecting_peer_commitment_signed {
+                       return Ok((None, None, None));
                }
 
                let (our_min_fee, our_max_fee) = self.calculate_closing_fee_limits(fee_estimator);
@@ -4243,8 +4756,11 @@ impl<SP: Deref> Channel<SP> where
                                                min_fee_satoshis: our_min_fee,
                                                max_fee_satoshis: our_max_fee,
                                        }),
-                               }), None))
-                       }
+                               }), None, None))
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
                }
        }
 
@@ -4274,10 +4790,10 @@ impl<SP: Deref> Channel<SP> where
                &mut self, signer_provider: &SP, their_features: &InitFeatures, msg: &msgs::Shutdown
        ) -> Result<(Option<msgs::Shutdown>, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), ChannelError>
        {
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent shutdown when we needed a channel_reestablish".to_owned()));
                }
-               if self.context.channel_state & !STATE_FLAGS < ChannelState::FundingSent as u32 {
+               if self.context.channel_state.is_pre_funded_state() {
                        // Spec says we should fail the connection, not the channel, but that's nonsense, there
                        // are plenty of reasons you may want to fail a channel pre-funding, and spec says you
                        // can do that via error message without getting a connection fail anyway...
@@ -4288,15 +4804,15 @@ impl<SP: Deref> Channel<SP> where
                                return Err(ChannelError::Close("Got shutdown with remote pending HTLCs".to_owned()));
                        }
                }
-               assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
+               assert!(!matches!(self.context.channel_state, ChannelState::ShutdownComplete));
 
                if !script::is_bolt2_compliant(&msg.scriptpubkey, their_features) {
-                       return Err(ChannelError::Warn(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_bytes().to_hex())));
+                       return Err(ChannelError::Warn(format!("Got a nonstandard scriptpubkey ({}) from remote peer", msg.scriptpubkey.to_hex_string())));
                }
 
                if self.context.counterparty_shutdown_scriptpubkey.is_some() {
                        if Some(&msg.scriptpubkey) != self.context.counterparty_shutdown_scriptpubkey.as_ref() {
-                               return Err(ChannelError::Warn(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_bytes().to_hex())));
+                               return Err(ChannelError::Warn(format!("Got shutdown request with a scriptpubkey ({}) which did not match their previous scriptpubkey.", msg.scriptpubkey.to_hex_string())));
                        }
                } else {
                        self.context.counterparty_shutdown_scriptpubkey = Some(msg.scriptpubkey.clone());
@@ -4305,7 +4821,7 @@ impl<SP: Deref> Channel<SP> where
                // If we have any LocalAnnounced updates we'll probably just get back an update_fail_htlc
                // immediately after the commitment dance, but we can send a Shutdown because we won't send
                // any further commitment updates after we set LocalShutdownSent.
-               let send_shutdown = (self.context.channel_state & ChannelState::LocalShutdownSent as u32) != ChannelState::LocalShutdownSent as u32;
+               let send_shutdown = !self.context.channel_state.is_local_shutdown_sent();
 
                let update_shutdown_script = match self.context.shutdown_scriptpubkey {
                        Some(_) => false,
@@ -4325,16 +4841,18 @@ impl<SP: Deref> Channel<SP> where
 
                // From here on out, we may not fail!
 
-               self.context.channel_state |= ChannelState::RemoteShutdownSent as u32;
+               self.context.channel_state.set_remote_shutdown_sent();
                self.context.update_time_counter += 1;
 
                let monitor_update = if update_shutdown_script {
                        self.context.latest_monitor_update_id += 1;
                        let monitor_update = ChannelMonitorUpdate {
                                update_id: self.context.latest_monitor_update_id,
+                               counterparty_node_id: Some(self.context.counterparty_node_id),
                                updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
                                        scriptpubkey: self.get_closing_scriptpubkey(),
                                }],
+                               channel_id: Some(self.context.channel_id()),
                        };
                        self.monitor_updating_paused(false, false, false, Vec::new(), Vec::new(), Vec::new());
                        self.push_ret_blockable_mon_update(monitor_update)
@@ -4361,7 +4879,7 @@ impl<SP: Deref> Channel<SP> where
                        }
                });
 
-               self.context.channel_state |= ChannelState::LocalShutdownSent as u32;
+               self.context.channel_state.set_local_shutdown_sent();
                self.context.update_time_counter += 1;
 
                Ok((shutdown, monitor_update, dropped_outbound_htlcs))
@@ -4392,13 +4910,13 @@ impl<SP: Deref> Channel<SP> where
 
        pub fn closing_signed<F: Deref>(
                &mut self, fee_estimator: &LowerBoundedFeeEstimator<F>, msg: &msgs::ClosingSigned)
-               -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>), ChannelError>
+               -> Result<(Option<msgs::ClosingSigned>, Option<Transaction>, Option<ShutdownResult>), ChannelError>
                where F::Target: FeeEstimator
        {
-               if self.context.channel_state & BOTH_SIDES_SHUTDOWN_MASK != BOTH_SIDES_SHUTDOWN_MASK {
+               if !self.context.channel_state.is_both_sides_shutdown() {
                        return Err(ChannelError::Close("Remote end sent us a closing_signed before both sides provided a shutdown".to_owned()));
                }
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == ChannelState::PeerDisconnected as u32 {
+               if self.context.channel_state.is_peer_disconnected() {
                        return Err(ChannelError::Close("Peer sent closing_signed when we needed a channel_reestablish".to_owned()));
                }
                if !self.context.pending_inbound_htlcs.is_empty() || !self.context.pending_outbound_htlcs.is_empty() {
@@ -4412,9 +4930,9 @@ impl<SP: Deref> Channel<SP> where
                        return Err(ChannelError::Close("Remote tried to send a closing_signed when we were supposed to propose the first one".to_owned()));
                }
 
-               if self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32 != 0 {
+               if self.context.channel_state.is_monitor_update_in_progress() {
                        self.context.pending_counterparty_closing_signed = Some(msg.clone());
-                       return Ok((None, None));
+                       return Ok((None, None, None));
                }
 
                let funding_redeemscript = self.context.get_funding_redeemscript();
@@ -4444,10 +4962,22 @@ impl<SP: Deref> Channel<SP> where
                assert!(self.context.shutdown_scriptpubkey.is_some());
                if let Some((last_fee, sig)) = self.context.last_sent_closing_fee {
                        if last_fee == msg.fee_satoshis {
+                               let shutdown_result = ShutdownResult {
+                                       closure_reason: ClosureReason::CooperativeClosure,
+                                       monitor_update: None,
+                                       dropped_outbound_htlcs: Vec::new(),
+                                       unbroadcasted_batch_funding_txid: self.context.unbroadcasted_batch_funding_txid(),
+                                       channel_id: self.context.channel_id,
+                                       user_channel_id: self.context.user_id,
+                                       channel_capacity_satoshis: self.context.channel_value_satoshis,
+                                       counterparty_node_id: self.context.counterparty_node_id,
+                                       unbroadcasted_funding_tx: self.context.unbroadcasted_funding(),
+                                       channel_funding_txo: self.context.get_funding_txo(),
+                               };
                                let tx = self.build_signed_closing_transaction(&mut closing_tx, &msg.signature, &sig);
-                               self.context.channel_state = ChannelState::ShutdownComplete as u32;
+                               self.context.channel_state = ChannelState::ShutdownComplete;
                                self.context.update_time_counter += 1;
-                               return Ok((None, Some(tx)));
+                               return Ok((None, Some(tx), Some(shutdown_result)));
                        }
                }
 
@@ -4466,13 +4996,26 @@ impl<SP: Deref> Channel<SP> where
                                                let sig = ecdsa
                                                        .sign_closing_transaction(&closing_tx, &self.context.secp_ctx)
                                                        .map_err(|_| ChannelError::Close("External signer refused to sign closing transaction".to_owned()))?;
-
-                                               let signed_tx = if $new_fee == msg.fee_satoshis {
-                                                       self.context.channel_state = ChannelState::ShutdownComplete as u32;
+                                               let (signed_tx, shutdown_result) = if $new_fee == msg.fee_satoshis {
+                                                       let shutdown_result = ShutdownResult {
+                                                               closure_reason: ClosureReason::CooperativeClosure,
+                                                               monitor_update: None,
+                                                               dropped_outbound_htlcs: Vec::new(),
+                                                               unbroadcasted_batch_funding_txid: self.context.unbroadcasted_batch_funding_txid(),
+                                                               channel_id: self.context.channel_id,
+                                                               user_channel_id: self.context.user_id,
+                                                               channel_capacity_satoshis: self.context.channel_value_satoshis,
+                                                               counterparty_node_id: self.context.counterparty_node_id,
+                                                               unbroadcasted_funding_tx: self.context.unbroadcasted_funding(),
+                                                               channel_funding_txo: self.context.get_funding_txo(),
+                                                       };
+                                                       self.context.channel_state = ChannelState::ShutdownComplete;
                                                        self.context.update_time_counter += 1;
                                                        let tx = self.build_signed_closing_transaction(&closing_tx, &msg.signature, &sig);
-                                                       Some(tx)
-                                               } else { None };
+                                                       (Some(tx), Some(shutdown_result))
+                                               } else {
+                                                       (None, None)
+                                               };
 
                                                self.context.last_sent_closing_fee = Some((used_fee, sig.clone()));
                                                Ok((Some(msgs::ClosingSigned {
@@ -4483,8 +5026,11 @@ impl<SP: Deref> Channel<SP> where
                                                                min_fee_satoshis: our_min_fee,
                                                                max_fee_satoshis: our_max_fee,
                                                        }),
-                                               }), signed_tx))
-                                       }
+                                               }), signed_tx, shutdown_result))
+                                       },
+                                       // TODO (taproot|arik)
+                                       #[cfg(taproot)]
+                                       _ => todo!()
                                }
                        }
                }
@@ -4588,7 +5134,7 @@ impl<SP: Deref> Channel<SP> where
        }
 
        pub fn get_cur_counterparty_commitment_transaction_number(&self) -> u64 {
-               self.context.cur_counterparty_commitment_transaction_number + 1 - if self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32) != 0 { 1 } else { 0 }
+               self.context.cur_counterparty_commitment_transaction_number + 1 - if self.context.channel_state.is_awaiting_remote_revoke() { 1 } else { 0 }
        }
 
        pub fn get_revoked_counterparty_commitment_transaction_number(&self) -> u64 {
@@ -4596,7 +5142,7 @@ impl<SP: Deref> Channel<SP> where
        }
 
        #[cfg(test)]
-       pub fn get_signer(&self) -> &ChannelSignerType<<SP::Target as SignerProvider>::Signer> {
+       pub fn get_signer(&self) -> &ChannelSignerType<SP> {
                &self.context.holder_signer
        }
 
@@ -4628,7 +5174,7 @@ impl<SP: Deref> Channel<SP> where
        /// Returns true if this channel has been marked as awaiting a monitor update to move forward.
        /// Allowed in any state (including after shutdown)
        pub fn is_awaiting_monitor_update(&self) -> bool {
-               (self.context.channel_state & ChannelState::MonitorUpdateInProgress as u32) != 0
+               self.context.channel_state.is_monitor_update_in_progress()
        }
 
        /// Gets the latest [`ChannelMonitorUpdate`] ID which has been released and is in-flight.
@@ -4670,17 +5216,18 @@ impl<SP: Deref> Channel<SP> where
        /// advanced state.
        pub fn is_awaiting_initial_mon_persist(&self) -> bool {
                if !self.is_awaiting_monitor_update() { return false; }
-               if self.context.channel_state &
-                       !(ChannelState::TheirChannelReady as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32 | ChannelState::WaitingForBatch as u32)
-                               == ChannelState::FundingSent as u32 {
+               if matches!(
+                       self.context.channel_state, ChannelState::AwaitingChannelReady(flags)
+                       if flags.clone().clear(AwaitingChannelReadyFlags::THEIR_CHANNEL_READY | FundedStateFlags::PEER_DISCONNECTED | FundedStateFlags::MONITOR_UPDATE_IN_PROGRESS | AwaitingChannelReadyFlags::WAITING_FOR_BATCH).is_empty()
+               ) {
                        // If we're not a 0conf channel, we'll be waiting on a monitor update with only
-                       // FundingSent set, though our peer could have sent their channel_ready.
+                       // AwaitingChannelReady set, though our peer could have sent their channel_ready.
                        debug_assert!(self.context.minimum_depth.unwrap_or(1) > 0);
                        return true;
                }
                if self.context.cur_holder_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 &&
                        self.context.cur_counterparty_commitment_transaction_number == INITIAL_COMMITMENT_NUMBER - 1 {
-                       // If we're a 0-conf channel, we'll move beyond FundingSent immediately even while
+                       // If we're a 0-conf channel, we'll move beyond AwaitingChannelReady immediately even while
                        // waiting for the initial monitor persistence. Thus, we check if our commitment
                        // transaction numbers have both been iterated only exactly once (for the
                        // funding_signed), and we're awaiting monitor update.
@@ -4702,27 +5249,25 @@ impl<SP: Deref> Channel<SP> where
 
        /// Returns true if our channel_ready has been sent
        pub fn is_our_channel_ready(&self) -> bool {
-               (self.context.channel_state & ChannelState::OurChannelReady as u32) != 0 || self.context.channel_state & !STATE_FLAGS >= ChannelState::ChannelReady as u32
+               matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(flags) if flags.is_set(AwaitingChannelReadyFlags::OUR_CHANNEL_READY)) ||
+                       matches!(self.context.channel_state, ChannelState::ChannelReady(_))
        }
 
        /// Returns true if our peer has either initiated or agreed to shut down the channel.
        pub fn received_shutdown(&self) -> bool {
-               (self.context.channel_state & ChannelState::RemoteShutdownSent as u32) != 0
+               self.context.channel_state.is_remote_shutdown_sent()
        }
 
        /// Returns true if we either initiated or agreed to shut down the channel.
        pub fn sent_shutdown(&self) -> bool {
-               (self.context.channel_state & ChannelState::LocalShutdownSent as u32) != 0
+               self.context.channel_state.is_local_shutdown_sent()
        }
 
        /// Returns true if this channel is fully shut down. True here implies that no further actions
        /// may/will be taken on this channel, and thus this object should be freed. Any future changes
        /// will be handled appropriately by the chain monitor.
        pub fn is_shutdown(&self) -> bool {
-               if (self.context.channel_state & ChannelState::ShutdownComplete as u32) == ChannelState::ShutdownComplete as u32  {
-                       assert!(self.context.channel_state == ChannelState::ShutdownComplete as u32);
-                       true
-               } else { false }
+               matches!(self.context.channel_state, ChannelState::ShutdownComplete)
        }
 
        pub fn channel_update_status(&self) -> ChannelUpdateStatus {
@@ -4751,37 +5296,44 @@ impl<SP: Deref> Channel<SP> where
                        return None;
                }
 
+               // If we're still pending the signature on a funding transaction, then we're not ready to send a
+               // channel_ready yet.
+               if self.context.signer_pending_funding {
+                       return None;
+               }
+
                // Note that we don't include ChannelState::WaitingForBatch as we don't want to send
                // channel_ready until the entire batch is ready.
-               let non_shutdown_state = self.context.channel_state & (!MULTI_STATE_FLAGS);
-               let need_commitment_update = if non_shutdown_state == ChannelState::FundingSent as u32 {
-                       self.context.channel_state |= ChannelState::OurChannelReady as u32;
+               let need_commitment_update = if matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(f) if f.clone().clear(FundedStateFlags::ALL.into()).is_empty()) {
+                       self.context.channel_state.set_our_channel_ready();
                        true
-               } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::TheirChannelReady as u32) {
-                       self.context.channel_state = ChannelState::ChannelReady as u32 | (self.context.channel_state & MULTI_STATE_FLAGS);
+               } else if matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(f) if f.clone().clear(FundedStateFlags::ALL.into()) == AwaitingChannelReadyFlags::THEIR_CHANNEL_READY) {
+                       self.context.channel_state = ChannelState::ChannelReady(self.context.channel_state.with_funded_state_flags_mask().into());
                        self.context.update_time_counter += 1;
                        true
-               } else if non_shutdown_state == (ChannelState::FundingSent as u32 | ChannelState::OurChannelReady as u32) {
+               } else if matches!(self.context.channel_state, ChannelState::AwaitingChannelReady(f) if f.clone().clear(FundedStateFlags::ALL.into()) == AwaitingChannelReadyFlags::OUR_CHANNEL_READY) {
                        // We got a reorg but not enough to trigger a force close, just ignore.
                        false
                } else {
-                       if self.context.funding_tx_confirmation_height != 0 && self.context.channel_state & !STATE_FLAGS < ChannelState::ChannelReady as u32 {
+                       if self.context.funding_tx_confirmation_height != 0 &&
+                               self.context.channel_state < ChannelState::ChannelReady(ChannelReadyFlags::new())
+                       {
                                // We should never see a funding transaction on-chain until we've received
                                // funding_signed (if we're an outbound channel), or seen funding_generated (if we're
                                // an inbound channel - before that we have no known funding TXID). The fuzzer,
                                // however, may do this and we shouldn't treat it as a bug.
                                #[cfg(not(fuzzing))]
-                               panic!("Started confirming a channel in a state pre-FundingSent: {}.\n\
+                               panic!("Started confirming a channel in a state pre-AwaitingChannelReady: {}.\n\
                                        Do NOT broadcast a funding transaction manually - let LDK do it for you!",
-                                       self.context.channel_state);
+                                       self.context.channel_state.to_u32());
                        }
                        // We got a reorg but not enough to trigger a force close, just ignore.
                        false
                };
 
                if need_commitment_update {
-                       if self.context.channel_state & (ChannelState::MonitorUpdateInProgress as u32) == 0 {
-                               if self.context.channel_state & (ChannelState::PeerDisconnected as u32) == 0 {
+                       if !self.context.channel_state.is_monitor_update_in_progress() {
+                               if !self.context.channel_state.is_peer_disconnected() {
                                        let next_per_commitment_point =
                                                self.context.holder_signer.as_ref().get_per_commitment_point(INITIAL_COMMITMENT_NUMBER - 1, &self.context.secp_ctx);
                                        return Some(msgs::ChannelReady {
@@ -4802,12 +5354,13 @@ impl<SP: Deref> Channel<SP> where
        /// In the second, we simply return an Err indicating we need to be force-closed now.
        pub fn transactions_confirmed<NS: Deref, L: Deref>(
                &mut self, block_hash: &BlockHash, height: u32, txdata: &TransactionData,
-               genesis_block_hash: BlockHash, node_signer: &NS, user_config: &UserConfig, logger: &L
+               chain_hash: ChainHash, node_signer: &NS, user_config: &UserConfig, logger: &L
        ) -> Result<(Option<msgs::ChannelReady>, Option<msgs::AnnouncementSignatures>), ClosureReason>
        where
                NS::Target: NodeSigner,
                L::Target: Logger
        {
+               let mut msgs = (None, None);
                if let Some(funding_txo) = self.context.get_funding_txo() {
                        for &(index_in_block, tx) in txdata.iter() {
                                // Check if the transaction is the expected funding transaction, and if it is,
@@ -4862,8 +5415,8 @@ impl<SP: Deref> Channel<SP> where
                                        // may have already happened for this block).
                                        if let Some(channel_ready) = self.check_get_channel_ready(height) {
                                                log_info!(logger, "Sending a channel_ready to our peer for channel {}", &self.context.channel_id);
-                                               let announcement_sigs = self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, height, logger);
-                                               return Ok((Some(channel_ready), announcement_sigs));
+                                               let announcement_sigs = self.get_announcement_sigs(node_signer, chain_hash, user_config, height, logger);
+                                               msgs = (Some(channel_ready), announcement_sigs);
                                        }
                                }
                                for inp in tx.input.iter() {
@@ -4874,7 +5427,7 @@ impl<SP: Deref> Channel<SP> where
                                }
                        }
                }
-               Ok((None, None))
+               Ok(msgs)
        }
 
        /// When a new block is connected, we check the height of the block against outbound holding
@@ -4889,19 +5442,19 @@ impl<SP: Deref> Channel<SP> where
        /// May return some HTLCs (and their payment_hash) which have timed out and should be failed
        /// back.
        pub fn best_block_updated<NS: Deref, L: Deref>(
-               &mut self, height: u32, highest_header_time: u32, genesis_block_hash: BlockHash,
+               &mut self, height: u32, highest_header_time: u32, chain_hash: ChainHash,
                node_signer: &NS, user_config: &UserConfig, logger: &L
        ) -> Result<(Option<msgs::ChannelReady>, Vec<(HTLCSource, PaymentHash)>, Option<msgs::AnnouncementSignatures>), ClosureReason>
        where
                NS::Target: NodeSigner,
                L::Target: Logger
        {
-               self.do_best_block_updated(height, highest_header_time, Some((genesis_block_hash, node_signer, user_config)), logger)
+               self.do_best_block_updated(height, highest_header_time, Some((chain_hash, node_signer, user_config)), logger)
        }
 
        fn do_best_block_updated<NS: Deref, L: Deref>(
                &mut self, height: u32, highest_header_time: u32,
-               genesis_node_signer: Option<(BlockHash, &NS, &UserConfig)>, logger: &L
+               chain_node_signer: Option<(ChainHash, &NS, &UserConfig)>, logger: &L
        ) -> Result<(Option<msgs::ChannelReady>, Vec<(HTLCSource, PaymentHash)>, Option<msgs::AnnouncementSignatures>), ClosureReason>
        where
                NS::Target: NodeSigner,
@@ -4927,16 +5480,15 @@ impl<SP: Deref> Channel<SP> where
                self.context.update_time_counter = cmp::max(self.context.update_time_counter, highest_header_time);
 
                if let Some(channel_ready) = self.check_get_channel_ready(height) {
-                       let announcement_sigs = if let Some((genesis_block_hash, node_signer, user_config)) = genesis_node_signer {
-                               self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, height, logger)
+                       let announcement_sigs = if let Some((chain_hash, node_signer, user_config)) = chain_node_signer {
+                               self.get_announcement_sigs(node_signer, chain_hash, user_config, height, logger)
                        } else { None };
                        log_info!(logger, "Sending a channel_ready to our peer for channel {}", &self.context.channel_id);
                        return Ok((Some(channel_ready), timed_out_htlcs, announcement_sigs));
                }
 
-               let non_shutdown_state = self.context.channel_state & (!MULTI_STATE_FLAGS);
-               if non_shutdown_state & !STATE_FLAGS >= ChannelState::ChannelReady as u32 ||
-                  (non_shutdown_state & ChannelState::OurChannelReady as u32) == ChannelState::OurChannelReady as u32 {
+               if matches!(self.context.channel_state, ChannelState::ChannelReady(_)) ||
+                       self.context.channel_state.is_our_channel_ready() {
                        let mut funding_tx_confirmations = height as i64 - self.context.funding_tx_confirmation_height as i64 + 1;
                        if self.context.funding_tx_confirmation_height == 0 {
                                // Note that check_get_channel_ready may reset funding_tx_confirmation_height to
@@ -4963,13 +5515,13 @@ impl<SP: Deref> Channel<SP> where
                                height >= self.context.channel_creation_height + FUNDING_CONF_DEADLINE_BLOCKS {
                        log_info!(logger, "Closing channel {} due to funding timeout", &self.context.channel_id);
                        // If funding_tx_confirmed_in is unset, the channel must not be active
-                       assert!(non_shutdown_state & !STATE_FLAGS <= ChannelState::ChannelReady as u32);
-                       assert_eq!(non_shutdown_state & ChannelState::OurChannelReady as u32, 0);
+                       assert!(self.context.channel_state <= ChannelState::ChannelReady(ChannelReadyFlags::new()));
+                       assert!(!self.context.channel_state.is_our_channel_ready());
                        return Err(ClosureReason::FundingTimedOut);
                }
 
-               let announcement_sigs = if let Some((genesis_block_hash, node_signer, user_config)) = genesis_node_signer {
-                       self.get_announcement_sigs(node_signer, genesis_block_hash, user_config, height, logger)
+               let announcement_sigs = if let Some((chain_hash, node_signer, user_config)) = chain_node_signer {
+                       self.get_announcement_sigs(node_signer, chain_hash, user_config, height, logger)
                } else { None };
                Ok((None, timed_out_htlcs, announcement_sigs))
        }
@@ -4986,7 +5538,7 @@ impl<SP: Deref> Channel<SP> where
                        // larger. If we don't know that time has moved forward, we can just set it to the last
                        // time we saw and it will be ignored.
                        let best_time = self.context.update_time_counter;
-                       match self.do_best_block_updated(reorg_height, best_time, None::<(BlockHash, &&NodeSigner, &UserConfig)>, logger) {
+                       match self.do_best_block_updated(reorg_height, best_time, None::<(ChainHash, &&dyn NodeSigner, &UserConfig)>, logger) {
                                Ok((channel_ready, timed_out_htlcs, announcement_sigs)) => {
                                        assert!(channel_ready.is_none(), "We can't generate a funding with 0 confirmations?");
                                        assert!(timed_out_htlcs.is_empty(), "We can't have accepted HTLCs with a timeout before our funding confirmation?");
@@ -5016,7 +5568,7 @@ impl<SP: Deref> Channel<SP> where
        ///
        /// [`ChannelReady`]: crate::ln::msgs::ChannelReady
        fn get_channel_announcement<NS: Deref>(
-               &self, node_signer: &NS, chain_hash: BlockHash, user_config: &UserConfig,
+               &self, node_signer: &NS, chain_hash: ChainHash, 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()));
@@ -5047,7 +5599,7 @@ impl<SP: Deref> Channel<SP> where
        }
 
        fn get_announcement_sigs<NS: Deref, L: Deref>(
-               &mut self, node_signer: &NS, genesis_block_hash: BlockHash, user_config: &UserConfig,
+               &mut self, node_signer: &NS, chain_hash: ChainHash, user_config: &UserConfig,
                best_block_height: u32, logger: &L
        ) -> Option<msgs::AnnouncementSignatures>
        where
@@ -5062,7 +5614,7 @@ impl<SP: Deref> Channel<SP> where
                        return None;
                }
 
-               if self.context.channel_state & ChannelState::PeerDisconnected as u32 != 0 {
+               if self.context.channel_state.is_peer_disconnected() {
                        log_trace!(logger, "Cannot create an announcement_signatures as our peer is disconnected");
                        return None;
                }
@@ -5072,7 +5624,7 @@ impl<SP: Deref> Channel<SP> where
                }
 
                log_trace!(logger, "Creating an announcement_signatures message for channel {}", &self.context.channel_id());
-               let announcement = match self.get_channel_announcement(node_signer, genesis_block_hash, user_config) {
+               let announcement = match self.get_channel_announcement(node_signer, chain_hash, user_config) {
                        Ok(a) => a,
                        Err(e) => {
                                log_trace!(logger, "{:?}", e);
@@ -5108,7 +5660,10 @@ impl<SP: Deref> Channel<SP> where
                                        node_signature: our_node_sig,
                                        bitcoin_signature: our_bitcoin_sig,
                                })
-                       }
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
                }
        }
 
@@ -5135,7 +5690,10 @@ impl<SP: Deref> Channel<SP> where
                                                bitcoin_signature_2: if were_node_one { their_bitcoin_sig } else { our_bitcoin_sig },
                                                contents: announcement,
                                        })
-                               }
+                               },
+                               // TODO (taproot|arik)
+                               #[cfg(taproot)]
+                               _ => todo!()
                        }
                } else {
                        Err(ChannelError::Ignore("Attempted to sign channel announcement before we'd received announcement_signatures".to_string()))
@@ -5146,7 +5704,7 @@ impl<SP: Deref> Channel<SP> where
        /// channel_announcement message which we can broadcast and storing our counterparty's
        /// signatures for later reconstruction/rebroadcast of the channel_announcement.
        pub fn announcement_signatures<NS: Deref>(
-               &mut self, node_signer: &NS, chain_hash: BlockHash, best_block_height: u32,
+               &mut self, node_signer: &NS, chain_hash: ChainHash, best_block_height: u32,
                msg: &msgs::AnnouncementSignatures, user_config: &UserConfig
        ) -> Result<msgs::ChannelAnnouncement, ChannelError> where NS::Target: NodeSigner {
                let announcement = self.get_channel_announcement(node_signer, chain_hash, user_config)?;
@@ -5176,7 +5734,7 @@ impl<SP: Deref> Channel<SP> where
        /// Gets a signed channel_announcement for this channel, if we previously received an
        /// announcement_signatures from our counterparty.
        pub fn get_signed_channel_announcement<NS: Deref>(
-               &self, node_signer: &NS, chain_hash: BlockHash, best_block_height: u32, user_config: &UserConfig
+               &self, node_signer: &NS, chain_hash: ChainHash, best_block_height: u32, user_config: &UserConfig
        ) -> Option<msgs::ChannelAnnouncement> where NS::Target: NodeSigner {
                if self.context.funding_tx_confirmation_height == 0 || self.context.funding_tx_confirmation_height + 5 > best_block_height {
                        return None;
@@ -5194,7 +5752,7 @@ impl<SP: Deref> Channel<SP> where
        /// May panic if called on a channel that wasn't immediately-previously
        /// self.remove_uncommitted_htlcs_and_mark_paused()'d
        pub fn get_channel_reestablish<L: Deref>(&mut self, logger: &L) -> msgs::ChannelReestablish where L::Target: Logger {
-               assert_eq!(self.context.channel_state & ChannelState::PeerDisconnected as u32, ChannelState::PeerDisconnected as u32);
+               assert!(self.context.channel_state.is_peer_disconnected());
                assert_ne!(self.context.cur_counterparty_commitment_transaction_number, INITIAL_COMMITMENT_NUMBER);
                // Prior to static_remotekey, my_current_per_commitment_point was critical to claiming
                // current to_remote balances. However, it no longer has any use, and thus is now simply
@@ -5230,7 +5788,7 @@ impl<SP: Deref> Channel<SP> where
                        // (which is one further, as they always revoke previous commitment transaction, not
                        // the one we send) so we have to decrement by 1. Note that if
                        // cur_counterparty_commitment_transaction_number is INITIAL_COMMITMENT_NUMBER we will have
-                       // dropped this channel on disconnect as it hasn't yet reached FundingSent so we can't
+                       // dropped this channel on disconnect as it hasn't yet reached AwaitingChannelReady so we can't
                        // overflow here.
                        next_remote_commitment_number: INITIAL_COMMITMENT_NUMBER - self.context.cur_counterparty_commitment_transaction_number - 1,
                        your_last_per_commitment_secret: remote_last_secret,
@@ -5253,13 +5811,13 @@ impl<SP: Deref> Channel<SP> where
        pub fn queue_add_htlc<F: Deref, L: Deref>(
                &mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
                onion_routing_packet: msgs::OnionPacket, skimmed_fee_msat: Option<u64>,
-               fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
+               blinding_point: Option<PublicKey>, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
        ) -> Result<(), ChannelError>
        where F::Target: FeeEstimator, L::Target: Logger
        {
                self
                        .send_htlc(amount_msat, payment_hash, cltv_expiry, source, onion_routing_packet, true,
-                               skimmed_fee_msat, fee_estimator, logger)
+                               skimmed_fee_msat, blinding_point, fee_estimator, logger)
                        .map(|msg_opt| assert!(msg_opt.is_none(), "We forced holding cell?"))
                        .map_err(|err| {
                                if let ChannelError::Ignore(_) = err { /* fine */ }
@@ -5287,11 +5845,15 @@ impl<SP: Deref> Channel<SP> where
        fn send_htlc<F: Deref, L: Deref>(
                &mut self, amount_msat: u64, payment_hash: PaymentHash, cltv_expiry: u32, source: HTLCSource,
                onion_routing_packet: msgs::OnionPacket, mut force_holding_cell: bool,
-               skimmed_fee_msat: Option<u64>, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
+               skimmed_fee_msat: Option<u64>, blinding_point: Option<PublicKey>,
+               fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
        ) -> Result<Option<msgs::UpdateAddHTLC>, ChannelError>
        where F::Target: FeeEstimator, L::Target: Logger
        {
-               if (self.context.channel_state & (ChannelState::ChannelReady as u32 | BOTH_SIDES_SHUTDOWN_MASK)) != (ChannelState::ChannelReady as u32) {
+               if !matches!(self.context.channel_state, ChannelState::ChannelReady(_)) ||
+                       self.context.channel_state.is_local_shutdown_sent() ||
+                       self.context.channel_state.is_remote_shutdown_sent()
+               {
                        return Err(ChannelError::Ignore("Cannot send HTLC until channel is fully established and we haven't started shutting down".to_owned()));
                }
                let channel_total_msat = self.context.channel_value_satoshis * 1000;
@@ -5314,7 +5876,7 @@ impl<SP: Deref> Channel<SP> where
                                available_balances.next_outbound_htlc_limit_msat)));
                }
 
-               if (self.context.channel_state & (ChannelState::PeerDisconnected as u32)) != 0 {
+               if self.context.channel_state.is_peer_disconnected() {
                        // Note that this should never really happen, if we're !is_live() on receipt of an
                        // incoming HTLC for relay will result in us rejecting the HTLC and we won't allow
                        // the user to send directly into a !is_live() channel. However, if we
@@ -5324,7 +5886,7 @@ impl<SP: Deref> Channel<SP> where
                        return Err(ChannelError::Ignore("Cannot send an HTLC while disconnected from channel counterparty".to_owned()));
                }
 
-               let need_holding_cell = (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0;
+               let need_holding_cell = !self.context.channel_state.can_generate_new_commitment();
                log_debug!(logger, "Pushing new outbound HTLC with hash {} for {} msat {}",
                        payment_hash, amount_msat,
                        if force_holding_cell { "into holding cell" }
@@ -5344,6 +5906,7 @@ impl<SP: Deref> Channel<SP> where
                                source,
                                onion_routing_packet,
                                skimmed_fee_msat,
+                               blinding_point,
                        });
                        return Ok(None);
                }
@@ -5355,6 +5918,7 @@ impl<SP: Deref> Channel<SP> where
                        cltv_expiry,
                        state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
                        source,
+                       blinding_point,
                        skimmed_fee_msat,
                });
 
@@ -5366,6 +5930,7 @@ impl<SP: Deref> Channel<SP> where
                        cltv_expiry,
                        onion_routing_packet,
                        skimmed_fee_msat,
+                       blinding_point,
                };
                self.context.next_holder_htlc_id += 1;
 
@@ -5418,6 +5983,7 @@ impl<SP: Deref> Channel<SP> where
                self.context.latest_monitor_update_id += 1;
                let monitor_update = ChannelMonitorUpdate {
                        update_id: self.context.latest_monitor_update_id,
+                       counterparty_node_id: Some(self.context.counterparty_node_id),
                        updates: vec![ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo {
                                commitment_txid: counterparty_commitment_txid,
                                htlc_outputs: htlcs.clone(),
@@ -5426,9 +5992,10 @@ impl<SP: Deref> Channel<SP> where
                                feerate_per_kw: Some(counterparty_commitment_tx.feerate_per_kw()),
                                to_broadcaster_value_sat: Some(counterparty_commitment_tx.to_broadcaster_value_sat()),
                                to_countersignatory_value_sat: Some(counterparty_commitment_tx.to_countersignatory_value_sat()),
-                       }]
+                       }],
+                       channel_id: Some(self.context.channel_id()),
                };
-               self.context.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
+               self.context.channel_state.set_awaiting_remote_revoke();
                monitor_update
        }
 
@@ -5482,8 +6049,12 @@ impl<SP: Deref> Channel<SP> where
                                                htlcs.push(htlc);
                                        }
 
-                                       let res = ecdsa.sign_counterparty_commitment(&commitment_stats.tx, commitment_stats.preimages, &self.context.secp_ctx)
-                                               .map_err(|_| ChannelError::Close("Failed to get signatures for new commitment_signed".to_owned()))?;
+                                       let res = ecdsa.sign_counterparty_commitment(
+                                                       &commitment_stats.tx,
+                                                       commitment_stats.inbound_htlc_preimages,
+                                                       commitment_stats.outbound_htlc_preimages,
+                                                       &self.context.secp_ctx,
+                                               ).map_err(|_| ChannelError::Ignore("Failed to get signatures for new commitment_signed".to_owned()))?;
                                        signature = res.0;
                                        htlc_signatures = res.1;
 
@@ -5496,7 +6067,7 @@ impl<SP: Deref> Channel<SP> where
                                                log_trace!(logger, "Signed remote HTLC tx {} with redeemscript {} with pubkey {} -> {} in channel {}",
                                                        encode::serialize_hex(&chan_utils::build_htlc_transaction(&counterparty_commitment_txid, commitment_stats.feerate_per_kw, self.context.get_holder_selected_contest_delay(), htlc, &self.context.channel_type, &counterparty_keys.broadcaster_delayed_payment_key, &counterparty_keys.revocation_key)),
                                                        encode::serialize_hex(&chan_utils::get_htlc_redeemscript(&htlc, &self.context.channel_type, &counterparty_keys)),
-                                                       log_bytes!(counterparty_keys.broadcaster_htlc_key.serialize()),
+                                                       log_bytes!(counterparty_keys.broadcaster_htlc_key.to_public_key().serialize()),
                                                        log_bytes!(htlc_sig.serialize_compact()[..]), &self.context.channel_id());
                                        }
                                }
@@ -5508,7 +6079,10 @@ impl<SP: Deref> Channel<SP> where
                                        #[cfg(taproot)]
                                        partial_signature_with_nonce: None,
                                }, (counterparty_commitment_txid, commitment_stats.htlcs_included)))
-                       }
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
                }
        }
 
@@ -5525,7 +6099,7 @@ impl<SP: Deref> Channel<SP> where
        where F::Target: FeeEstimator, L::Target: Logger
        {
                let send_res = self.send_htlc(amount_msat, payment_hash, cltv_expiry, source,
-                       onion_routing_packet, false, skimmed_fee_msat, fee_estimator, logger);
+                       onion_routing_packet, false, skimmed_fee_msat, None, fee_estimator, logger);
                if let Err(e) = &send_res { if let ChannelError::Ignore(_) = e {} else { debug_assert!(false, "Sending cannot trigger channel failure"); } }
                match send_res? {
                        Some(_) => {
@@ -5537,21 +6111,24 @@ impl<SP: Deref> Channel<SP> where
                }
        }
 
-       pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<(), ChannelError> {
-               self.context.counterparty_forwarding_info = Some(CounterpartyForwardingInfo {
+       /// Applies the `ChannelUpdate` and returns a boolean indicating whether a change actually
+       /// happened.
+       pub fn channel_update(&mut self, msg: &msgs::ChannelUpdate) -> Result<bool, ChannelError> {
+               let new_forwarding_info = Some(CounterpartyForwardingInfo {
                        fee_base_msat: msg.contents.fee_base_msat,
                        fee_proportional_millionths: msg.contents.fee_proportional_millionths,
                        cltv_expiry_delta: msg.contents.cltv_expiry_delta
                });
+               let did_change = self.context.counterparty_forwarding_info != new_forwarding_info;
+               if did_change {
+                       self.context.counterparty_forwarding_info = new_forwarding_info;
+               }
 
-               Ok(())
+               Ok(did_change)
        }
 
        /// Begins the shutdown process, getting a message for the remote peer and returning all
        /// holding cell HTLCs for payment failure.
-       ///
-       /// May jump to the channel being fully shutdown (see [`Self::is_shutdown`]) in which case no
-       /// [`ChannelMonitorUpdate`] will be returned).
        pub fn get_shutdown(&mut self, signer_provider: &SP, their_features: &InitFeatures,
                target_feerate_sats_per_kw: Option<u32>, override_shutdown_script: Option<ShutdownScript>)
        -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
@@ -5561,32 +6138,23 @@ impl<SP: Deref> Channel<SP> where
                                return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
                        }
                }
-               if self.context.channel_state & BOTH_SIDES_SHUTDOWN_MASK != 0 {
-                       if (self.context.channel_state & ChannelState::LocalShutdownSent as u32) == ChannelState::LocalShutdownSent as u32 {
-                               return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
-                       }
-                       else if (self.context.channel_state & ChannelState::RemoteShutdownSent as u32) == ChannelState::RemoteShutdownSent as u32 {
-                               return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
-                       }
+               if self.context.channel_state.is_local_shutdown_sent() {
+                       return Err(APIError::APIMisuseError{err: "Shutdown already in progress".to_owned()});
+               }
+               else if self.context.channel_state.is_remote_shutdown_sent() {
+                       return Err(APIError::ChannelUnavailable{err: "Shutdown already in progress by remote".to_owned()});
                }
                if self.context.shutdown_scriptpubkey.is_some() && override_shutdown_script.is_some() {
                        return Err(APIError::APIMisuseError{err: "Cannot override shutdown script for a channel with one already set".to_owned()});
                }
-               assert_eq!(self.context.channel_state & ChannelState::ShutdownComplete as u32, 0);
-               if self.context.channel_state & (ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32) != 0 {
+               assert!(!matches!(self.context.channel_state, ChannelState::ShutdownComplete));
+               if self.context.channel_state.is_peer_disconnected() || self.context.channel_state.is_monitor_update_in_progress() {
                        return Err(APIError::ChannelUnavailable{err: "Cannot begin shutdown while peer is disconnected or we're waiting on a monitor update, maybe force-close instead?".to_owned()});
                }
 
-               // If we haven't funded the channel yet, we don't need to bother ensuring the shutdown
-               // script is set, we just force-close and call it a day.
-               let mut chan_closed = false;
-               if self.context.channel_state & !STATE_FLAGS < ChannelState::FundingSent as u32 {
-                       chan_closed = true;
-               }
-
                let update_shutdown_script = match self.context.shutdown_scriptpubkey {
                        Some(_) => false,
-                       None if !chan_closed => {
+                       None => {
                                // use override shutdown script if provided
                                let shutdown_scriptpubkey = match override_shutdown_script {
                                        Some(script) => script,
@@ -5604,25 +6172,22 @@ impl<SP: Deref> Channel<SP> where
                                self.context.shutdown_scriptpubkey = Some(shutdown_scriptpubkey);
                                true
                        },
-                       None => false,
                };
 
                // From here on out, we may not fail!
                self.context.target_closing_feerate_sats_per_kw = target_feerate_sats_per_kw;
-               if self.context.channel_state & !STATE_FLAGS < ChannelState::FundingSent as u32 {
-                       self.context.channel_state = ChannelState::ShutdownComplete as u32;
-               } else {
-                       self.context.channel_state |= ChannelState::LocalShutdownSent as u32;
-               }
+               self.context.channel_state.set_local_shutdown_sent();
                self.context.update_time_counter += 1;
 
                let monitor_update = if update_shutdown_script {
                        self.context.latest_monitor_update_id += 1;
                        let monitor_update = ChannelMonitorUpdate {
                                update_id: self.context.latest_monitor_update_id,
+                               counterparty_node_id: Some(self.context.counterparty_node_id),
                                updates: vec![ChannelMonitorUpdateStep::ShutdownScript {
                                        scriptpubkey: self.get_closing_scriptpubkey(),
                                }],
+                               channel_id: Some(self.context.channel_id()),
                        };
                        self.monitor_updating_paused(false, false, false, Vec::new(), Vec::new(), Vec::new());
                        self.push_ret_blockable_mon_update(monitor_update)
@@ -5675,7 +6240,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
        pub fn new<ES: 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
+               outbound_scid_alias: u64, temporary_channel_id: Option<ChannelId>
        ) -> Result<OutboundV1Channel<SP>, APIError>
        where ES::Target: EntropySource,
              F::Target: FeeEstimator
@@ -5708,16 +6273,16 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                let channel_type = Self::get_initial_channel_type(&config, their_features);
                debug_assert!(channel_type.is_subset(&channelmanager::provided_channel_type_features(&config)));
 
-               let commitment_conf_target = if channel_type.supports_anchors_zero_fee_htlc_tx() {
-                       ConfirmationTarget::MempoolMinimum
+               let (commitment_conf_target, anchor_outputs_value_msat)  = if channel_type.supports_anchors_zero_fee_htlc_tx() {
+                       (ConfirmationTarget::AnchorChannelFee, ANCHOR_OUTPUT_VALUE_SATOSHI * 2 * 1000)
                } else {
-                       ConfirmationTarget::Normal
+                       (ConfirmationTarget::NonAnchorChannelFee, 0)
                };
                let commitment_feerate = fee_estimator.bounded_sat_per_1000_weight(commitment_conf_target);
 
                let value_to_self_msat = channel_value_satoshis * 1000 - push_msat;
                let commitment_tx_fee = commit_tx_fee_msat(commitment_feerate, MIN_AFFORDABLE_HTLC_COUNT, &channel_type);
-               if value_to_self_msat < commitment_tx_fee {
+               if value_to_self_msat.saturating_sub(anchor_outputs_value_msat) < commitment_tx_fee {
                        return Err(APIError::APIMisuseError{ err: format!("Funding amount ({}) can't even pay fee for initial commitment transaction fee of {}.", value_to_self_msat / 1000, commitment_tx_fee / 1000) });
                }
 
@@ -5737,12 +6302,12 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                        }
                }
 
-               let destination_script = match signer_provider.get_destination_script() {
+               let destination_script = match signer_provider.get_destination_script(channel_keys_id) {
                        Ok(script) => script,
                        Err(_) => return Err(APIError::ChannelUnavailable { err: "Failed to get destination script".to_owned()}),
                };
 
-               let temporary_channel_id = ChannelId::temporary_from_entropy_source(entropy_source);
+               let temporary_channel_id = temporary_channel_id.unwrap_or_else(|| ChannelId::temporary_from_entropy_source(entropy_source));
 
                Ok(Self {
                        context: ChannelContext {
@@ -5760,7 +6325,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
 
                                channel_id: temporary_channel_id,
                                temporary_channel_id: Some(temporary_channel_id),
-                               channel_state: ChannelState::OurInitSent as u32,
+                               channel_state: ChannelState::NegotiatingFunding(NegotiatingFundingFlags::OUR_INIT_SENT),
                                announcement_sigs_state: AnnouncementSigsState::NotSent,
                                secp_ctx,
                                channel_value_satoshis,
@@ -5793,6 +6358,9 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                                monitor_pending_failures: Vec::new(),
                                monitor_pending_finalized_fulfills: Vec::new(),
 
+                               signer_pending_commitment_update: false,
+                               signer_pending_funding: false,
+
                                #[cfg(debug_assertions)]
                                holder_max_commitment_tx_output: Mutex::new((channel_value_satoshis * 1000 - push_msat, push_msat)),
                                #[cfg(debug_assertions)]
@@ -5800,6 +6368,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
 
                                last_sent_closing_fee: None,
                                pending_counterparty_closing_signed: None,
+                               expecting_peer_commitment_signed: false,
                                closing_fee_limits: None,
                                target_closing_feerate_sats_per_kw: None,
 
@@ -5873,17 +6442,36 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                })
        }
 
-       /// If an Err is returned, it is a ChannelError::Close (for get_funding_created)
-       fn get_funding_created_signature<L: Deref>(&mut self, logger: &L) -> Result<Signature, ChannelError> where L::Target: Logger {
+       /// Only allowed after [`ChannelContext::channel_transaction_parameters`] is set.
+       fn get_funding_created_msg<L: Deref>(&mut self, logger: &L) -> Option<msgs::FundingCreated> 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;
-               match &self.context.holder_signer {
+               let signature = match &self.context.holder_signer {
                        // TODO (taproot|arik): move match into calling method for Taproot
                        ChannelSignerType::Ecdsa(ecdsa) => {
-                               Ok(ecdsa.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)
-                       }
+                               ecdsa.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), Vec::new(), &self.context.secp_ctx)
+                                       .map(|(sig, _)| sig).ok()?
+                       },
+                       // TODO (taproot|arik)
+                       #[cfg(taproot)]
+                       _ => todo!()
+               };
+
+               if self.context.signer_pending_funding {
+                       log_trace!(logger, "Counterparty commitment signature ready for funding_created message: clearing signer_pending_funding");
+                       self.context.signer_pending_funding = false;
                }
+
+               Some(msgs::FundingCreated {
+                       temporary_channel_id: self.context.temporary_channel_id.unwrap(),
+                       funding_txid: self.context.channel_transaction_parameters.funding_outpoint.as_ref().unwrap().txid,
+                       funding_output_index: self.context.channel_transaction_parameters.funding_outpoint.as_ref().unwrap().index,
+                       signature,
+                       #[cfg(taproot)]
+                       partial_signature_with_nonce: None,
+                       #[cfg(taproot)]
+                       next_local_nonce: None,
+               })
        }
 
        /// Updates channel state with knowledge of the funding transaction's txid/index, and generates
@@ -5893,38 +6481,30 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
        /// 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_funding_created<L: Deref>(mut self, funding_transaction: Transaction, funding_txo: OutPoint, is_batch_funding: bool, logger: &L)
-       -> Result<(Channel<SP>, msgs::FundingCreated), (Self, ChannelError)> where L::Target: Logger {
+       pub fn get_funding_created<L: Deref>(&mut self, funding_transaction: Transaction, funding_txo: OutPoint, is_batch_funding: bool, logger: &L)
+       -> Result<Option<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) {
+               if !matches!(
+                       self.context.channel_state, ChannelState::NegotiatingFunding(flags)
+                       if flags == (NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT)
+               ) {
                        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.as_mut().provide_channel_parameters(&self.context.channel_transaction_parameters);
-
-               let signature = match self.get_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;
+               self.context.channel_transaction_parameters.funding_outpoint = Some(funding_txo);
+               self.context.holder_signer.as_mut().provide_channel_parameters(&self.context.channel_transaction_parameters);
 
                // 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.channel_state = ChannelState::FundingNegotiated;
+               self.context.channel_id = ChannelId::v1_from_funding_outpoint(funding_txo);
 
                // If the funding transaction is a coinbase transaction, we need to set the minimum depth to 100.
                // We can skip this if it is a zero-conf channel.
@@ -5937,20 +6517,20 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                self.context.funding_transaction = Some(funding_transaction);
                self.context.is_batch_funding = Some(()).filter(|_| is_batch_funding);
 
-               let channel = Channel {
-                       context: self.context,
-               };
+               let funding_created = self.get_funding_created_msg(logger);
+               if funding_created.is_none() {
+                       #[cfg(not(async_signing))] {
+                               panic!("Failed to get signature for new funding creation");
+                       }
+                       #[cfg(async_signing)] {
+                               if !self.context.signer_pending_funding {
+                                       log_trace!(logger, "funding_created awaiting signer; setting signer_pending_funding");
+                                       self.context.signer_pending_funding = true;
+                               }
+                       }
+               }
 
-               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,
-               }))
+               Ok(funding_created)
        }
 
        fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
@@ -5980,12 +6560,19 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
        /// 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<F: Deref>(
-               &mut self, chain_hash: BlockHash, fee_estimator: &LowerBoundedFeeEstimator<F>
+               &mut self, chain_hash: ChainHash, fee_estimator: &LowerBoundedFeeEstimator<F>
        ) -> Result<msgs::OpenChannel, ()>
        where
                F::Target: FeeEstimator
        {
-               if !self.context.is_outbound() || self.context.channel_state != ChannelState::OurInitSent as u32 { return Err(()); }
+               if !self.context.is_outbound() ||
+                       !matches!(
+                               self.context.channel_state, ChannelState::NegotiatingFunding(flags)
+                               if flags == NegotiatingFundingFlags::OUR_INIT_SENT
+                       )
+               {
+                       return Err(());
+               }
                if self.context.channel_type == ChannelTypeFeatures::only_static_remote_key() {
                        // We've exhausted our options
                        return Err(());
@@ -6001,7 +6588,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                // whatever reason.
                if self.context.channel_type.supports_anchors_zero_fee_htlc_tx() {
                        self.context.channel_type.clear_anchors_zero_fee_htlc_tx();
-                       self.context.feerate_per_kw = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::Normal);
+                       self.context.feerate_per_kw = fee_estimator.bounded_sat_per_1000_weight(ConfirmationTarget::NonAnchorChannelFee);
                        assert!(!self.context.channel_transaction_parameters.channel_type_features.supports_anchors_nonzero_fee_htlc_tx());
                } else if self.context.channel_type.supports_scid_privacy() {
                        self.context.channel_type.clear_scid_privacy();
@@ -6012,11 +6599,11 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                Ok(self.get_open_channel(chain_hash))
        }
 
-       pub fn get_open_channel(&self, chain_hash: BlockHash) -> msgs::OpenChannel {
+       pub fn get_open_channel(&self, chain_hash: ChainHash) -> 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 {
+               if self.context.have_received_message() {
                        panic!("Cannot generate an open_channel after we've moved forward");
                }
 
@@ -6040,10 +6627,10 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                        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,
+                       revocation_basepoint: keys.revocation_basepoint.to_public_key(),
                        payment_point: keys.payment_point,
-                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
-                       htlc_basepoint: keys.htlc_basepoint,
+                       delayed_payment_basepoint: keys.delayed_payment_basepoint.to_public_key(),
+                       htlc_basepoint: keys.htlc_basepoint.to_public_key(),
                        first_per_commitment_point,
                        channel_flags: if self.context.config.announced_channel {1} else {0},
                        shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
@@ -6062,7 +6649,7 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                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 {
+               if !matches!(self.context.channel_state, ChannelState::NegotiatingFunding(flags) if flags == NegotiatingFundingFlags::OUR_INIT_SENT) {
                        return Err(ChannelError::Close("Got an accept_channel message at a strange time".to_owned()));
                }
                if msg.dust_limit_satoshis > 21000000 * 100000000 {
@@ -6165,10 +6752,10 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
 
                let counterparty_pubkeys = ChannelPublicKeys {
                        funding_pubkey: msg.funding_pubkey,
-                       revocation_basepoint: msg.revocation_basepoint,
+                       revocation_basepoint: RevocationBasepoint::from(msg.revocation_basepoint),
                        payment_point: msg.payment_point,
-                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
-                       htlc_basepoint: msg.htlc_basepoint
+                       delayed_payment_basepoint: DelayedPaymentBasepoint::from(msg.delayed_payment_basepoint),
+                       htlc_basepoint: HtlcBasepoint::from(msg.htlc_basepoint)
                };
 
                self.context.channel_transaction_parameters.counterparty_parameters = Some(CounterpartyChannelTransactionParameters {
@@ -6179,11 +6766,119 @@ impl<SP: Deref> OutboundV1Channel<SP> where SP::Target: SignerProvider {
                self.context.counterparty_cur_commitment_point = Some(msg.first_per_commitment_point);
                self.context.counterparty_shutdown_scriptpubkey = counterparty_shutdown_scriptpubkey;
 
-               self.context.channel_state = ChannelState::OurInitSent as u32 | ChannelState::TheirInitSent as u32;
+               self.context.channel_state = ChannelState::NegotiatingFunding(
+                       NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT
+               );
                self.context.inbound_handshake_limits_override = None; // We're done enforcing limits on our peer's handshake now.
 
                Ok(())
        }
+
+       /// 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<L: Deref>(
+               mut self, msg: &msgs::FundingSigned, best_block: BestBlock, signer_provider: &SP, logger: &L
+       ) -> Result<(Channel<SP>, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>), (OutboundV1Channel<SP>, ChannelError)>
+       where
+               L::Target: Logger
+       {
+               if !self.context.is_outbound() {
+                       return Err((self, ChannelError::Close("Received funding_signed for an inbound channel?".to_owned())));
+               }
+               if !matches!(self.context.channel_state, ChannelState::FundingNegotiated) {
+                       return Err((self, 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 {}",
+                       &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((self, 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()
+               );
+
+               let validated =
+                       self.context.holder_signer.as_ref().validate_holder_commitment(&holder_commitment_tx, Vec::new());
+               if validated.is_err() {
+                       return Err((self, 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, self.context.channel_id());
+               channel_monitor.provide_initial_counterparty_commitment_tx(
+                       counterparty_initial_bitcoin_tx.txid, Vec::new(),
+                       self.context.cur_counterparty_commitment_transaction_number,
+                       self.context.counterparty_cur_commitment_point.unwrap(),
+                       counterparty_initial_commitment_tx.feerate_per_kw(),
+                       counterparty_initial_commitment_tx.to_broadcaster_value_sat(),
+                       counterparty_initial_commitment_tx.to_countersignatory_value_sat(), logger);
+
+               assert!(!self.context.channel_state.is_monitor_update_in_progress()); // We have no had any monitor(s) yet to fail update!
+               if self.context.is_batch_funding() {
+                       self.context.channel_state = ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::WAITING_FOR_BATCH);
+               } else {
+                       self.context.channel_state = ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::new());
+               }
+               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 {}", &self.context.channel_id());
+
+               let mut channel = Channel { context: self.context };
+
+               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, channel_monitor))
+       }
+
+       /// Indicates that the signer may have some signatures for us, so we should retry if we're
+       /// blocked.
+       #[cfg(async_signing)]
+       pub fn signer_maybe_unblocked<L: Deref>(&mut self, logger: &L) -> Option<msgs::FundingCreated> where L::Target: Logger {
+               if self.context.signer_pending_funding && self.context.is_outbound() {
+                       log_trace!(logger, "Signer unblocked a funding_created");
+                       self.get_funding_created_msg(logger)
+               } else { None }
+       }
 }
 
 /// A not-yet-funded inbound (from counterparty) channel using V1 channel establishment.
@@ -6192,6 +6887,41 @@ pub(super) struct InboundV1Channel<SP: Deref> where SP::Target: SignerProvider {
        pub unfunded_context: UnfundedChannelContext,
 }
 
+/// Fetches the [`ChannelTypeFeatures`] that will be used for a channel built from a given
+/// [`msgs::OpenChannel`].
+pub(super) fn channel_type_from_open_channel(
+       msg: &msgs::OpenChannel, their_features: &InitFeatures,
+       our_supported_features: &ChannelTypeFeatures
+) -> Result<ChannelTypeFeatures, ChannelError> {
+       if let Some(channel_type) = &msg.channel_type {
+               if channel_type.supports_any_optional_bits() {
+                       return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
+               }
+
+               // We only support the channel types defined by the `ChannelManager` in
+               // `provided_channel_type_features`. The channel type must always support
+               // `static_remote_key`.
+               if !channel_type.requires_static_remote_key() {
+                       return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
+               }
+               // Make sure we support all of the features behind the channel type.
+               if !channel_type.is_subset(our_supported_features) {
+                       return Err(ChannelError::Close("Channel Type contains unsupported features".to_owned()));
+               }
+               let announced_channel = if (msg.channel_flags & 1) == 1 { true } else { false };
+               if channel_type.requires_scid_privacy() && announced_channel {
+                       return Err(ChannelError::Close("SCID Alias/Privacy Channel Type cannot be set on a public channel".to_owned()));
+               }
+               Ok(channel_type.clone())
+       } 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()));
+               }
+               Ok(channel_type)
+       }
+}
+
 impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
        /// Creates a new channel from a remote sides' request for one.
        /// Assumes chain_hash has already been checked and corresponds with what we expect!
@@ -6205,46 +6935,22 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                          F::Target: FeeEstimator,
                          L::Target: Logger,
        {
+               let logger = WithContext::from(logger, Some(counterparty_node_id), Some(msg.temporary_channel_id));
                let announced_channel = if (msg.channel_flags & 1) == 1 { true } else { false };
 
                // First check the channel type is known, failing before we do anything else if we don't
                // support this channel type.
-               let channel_type = if let Some(channel_type) = &msg.channel_type {
-                       if channel_type.supports_any_optional_bits() {
-                               return Err(ChannelError::Close("Channel Type field contained optional bits - this is not allowed".to_owned()));
-                       }
-
-                       // We only support the channel types defined by the `ChannelManager` in
-                       // `provided_channel_type_features`. The channel type must always support
-                       // `static_remote_key`.
-                       if !channel_type.requires_static_remote_key() {
-                               return Err(ChannelError::Close("Channel Type was not understood - we require static remote key".to_owned()));
-                       }
-                       // Make sure we support all of the features behind the channel type.
-                       if !channel_type.is_subset(our_supported_features) {
-                               return Err(ChannelError::Close("Channel Type contains unsupported features".to_owned()));
-                       }
-                       if channel_type.requires_scid_privacy() && announced_channel {
-                               return Err(ChannelError::Close("SCID Alias/Privacy Channel Type cannot be set on a public channel".to_owned()));
-                       }
-                       channel_type.clone()
-               } 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()));
-                       }
-                       channel_type
-               };
+               let channel_type = channel_type_from_open_channel(msg, their_features, our_supported_features)?;
 
                let channel_keys_id = signer_provider.generate_channel_keys_id(true, msg.funding_satoshis, user_id);
                let holder_signer = signer_provider.derive_channel_signer(msg.funding_satoshis, channel_keys_id);
                let pubkeys = holder_signer.pubkeys().clone();
                let counterparty_pubkeys = ChannelPublicKeys {
                        funding_pubkey: msg.funding_pubkey,
-                       revocation_basepoint: msg.revocation_basepoint,
+                       revocation_basepoint: RevocationBasepoint::from(msg.revocation_basepoint),
                        payment_point: msg.payment_point,
-                       delayed_payment_basepoint: msg.delayed_payment_basepoint,
-                       htlc_basepoint: msg.htlc_basepoint
+                       delayed_payment_basepoint: DelayedPaymentBasepoint::from(msg.delayed_payment_basepoint),
+                       htlc_basepoint: HtlcBasepoint::from(msg.htlc_basepoint)
                };
 
                if config.channel_handshake_config.our_to_self_delay < BREAKDOWN_TIMEOUT {
@@ -6271,7 +6977,7 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                if msg.htlc_minimum_msat >= full_channel_value_msat {
                        return Err(ChannelError::Close(format!("Minimum htlc value ({}) was larger than full channel value ({})", msg.htlc_minimum_msat, full_channel_value_msat)));
                }
-               Channel::<SP>::check_remote_fee(&channel_type, fee_estimator, msg.feerate_per_kw, None, logger)?;
+               Channel::<SP>::check_remote_fee(&channel_type, fee_estimator, msg.feerate_per_kw, None, &&logger)?;
 
                let max_counterparty_selected_contest_delay = u16::min(config.channel_handshake_limits.their_to_self_delay, MAX_LOCAL_BREAKDOWN_TIMEOUT);
                if msg.to_self_delay > max_counterparty_selected_contest_delay {
@@ -6334,13 +7040,18 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
 
                // check if the funder's amount for the initial commitment tx is sufficient
                // for full fee payment plus a few HTLCs to ensure the channel will be useful.
+               let anchor_outputs_value = if channel_type.supports_anchors_zero_fee_htlc_tx() {
+                       ANCHOR_OUTPUT_VALUE_SATOSHI * 2
+               } else {
+                       0
+               };
                let funders_amount_msat = msg.funding_satoshis * 1000 - msg.push_msat;
                let commitment_tx_fee = commit_tx_fee_msat(msg.feerate_per_kw, MIN_AFFORDABLE_HTLC_COUNT, &channel_type) / 1000;
-               if funders_amount_msat / 1000 < commitment_tx_fee {
-                       return Err(ChannelError::Close(format!("Funding amount ({} sats) can't even pay fee for initial commitment transaction fee of {} sats.", funders_amount_msat / 1000, commitment_tx_fee)));
+               if (funders_amount_msat / 1000).saturating_sub(anchor_outputs_value) < commitment_tx_fee {
+                       return Err(ChannelError::Close(format!("Funding amount ({} sats) can't even pay fee for initial commitment transaction fee of {} sats.", (funders_amount_msat / 1000).saturating_sub(anchor_outputs_value), commitment_tx_fee)));
                }
 
-               let to_remote_satoshis = funders_amount_msat / 1000 - commitment_tx_fee;
+               let to_remote_satoshis = funders_amount_msat / 1000 - commitment_tx_fee - anchor_outputs_value;
                // While it's reasonable for us to not meet the channel reserve initially (if they don't
                // want to push much to us), our counterparty should always have more than our reserve.
                if to_remote_satoshis < holder_selected_channel_reserve_satoshis {
@@ -6380,7 +7091,7 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                        }
                }
 
-               let destination_script = match signer_provider.get_destination_script() {
+               let destination_script = match signer_provider.get_destination_script(channel_keys_id) {
                        Ok(script) => script,
                        Err(_) => return Err(ChannelError::Close("Failed to get destination script".to_owned())),
                };
@@ -6410,7 +7121,9 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
 
                                temporary_channel_id: Some(msg.temporary_channel_id),
                                channel_id: msg.temporary_channel_id,
-                               channel_state: (ChannelState::OurInitSent as u32) | (ChannelState::TheirInitSent as u32),
+                               channel_state: ChannelState::NegotiatingFunding(
+                                       NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT
+                               ),
                                announcement_sigs_state: AnnouncementSigsState::NotSent,
                                secp_ctx,
 
@@ -6442,6 +7155,9 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                                monitor_pending_failures: Vec::new(),
                                monitor_pending_finalized_fulfills: Vec::new(),
 
+                               signer_pending_commitment_update: false,
+                               signer_pending_funding: false,
+
                                #[cfg(debug_assertions)]
                                holder_max_commitment_tx_output: Mutex::new((msg.push_msat, msg.funding_satoshis * 1000 - msg.push_msat)),
                                #[cfg(debug_assertions)]
@@ -6449,6 +7165,7 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
 
                                last_sent_closing_fee: None,
                                pending_counterparty_closing_signed: None,
+                               expecting_peer_commitment_signed: false,
                                closing_fee_limits: None,
                                target_closing_feerate_sats_per_kw: None,
 
@@ -6536,7 +7253,10 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                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) {
+               if !matches!(
+                       self.context.channel_state, ChannelState::NegotiatingFunding(flags)
+                       if flags == (NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT)
+               ) {
                        panic!("Tried to send accept_channel after channel had moved forward");
                }
                if self.context.cur_holder_commitment_transaction_number != INITIAL_COMMITMENT_NUMBER {
@@ -6565,10 +7285,10 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                        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,
+                       revocation_basepoint: keys.revocation_basepoint.to_public_key(),
                        payment_point: keys.payment_point,
-                       delayed_payment_basepoint: keys.delayed_payment_basepoint,
-                       htlc_basepoint: keys.htlc_basepoint,
+                       delayed_payment_basepoint: keys.delayed_payment_basepoint.to_public_key(),
+                       htlc_basepoint: keys.htlc_basepoint.to_public_key(),
                        first_per_commitment_point,
                        shutdown_scriptpubkey: Some(match &self.context.shutdown_scriptpubkey {
                                Some(script) => script.clone().into_inner(),
@@ -6589,53 +7309,37 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                self.generate_accept_channel_message()
        }
 
-       fn funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<(CommitmentTransaction, CommitmentTransaction, Signature), ChannelError> where L::Target: Logger {
+       fn check_funding_created_signature<L: Deref>(&mut self, sig: &Signature, logger: &L) -> Result<CommitmentTransaction, 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), &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 {}",
-                       &self.context.channel_id(), counterparty_initial_bitcoin_tx.txid, encode::serialize_hex(&counterparty_initial_bitcoin_tx.transaction));
-
-               match &self.context.holder_signer {
-                       // TODO (arik): move match into calling method for Taproot
-                       ChannelSignerType::Ecdsa(ecdsa) => {
-                               let counterparty_signature = ecdsa.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;
+               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), &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());
 
-                               // We sign "counterparty" commitment transaction, allowing them to broadcast the tx if they wish.
-                               Ok((counterparty_initial_commitment_tx, initial_commitment_tx, counterparty_signature))
-                       }
-               }
+               Ok(initial_commitment_tx)
        }
 
        pub fn funding_created<L: Deref>(
                mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
-       ) -> Result<(Channel<SP>, msgs::FundingSigned, ChannelMonitor<<SP::Target as SignerProvider>::Signer>), (Self, ChannelError)>
+       ) -> Result<(Channel<SP>, Option<msgs::FundingSigned>, ChannelMonitor<<SP::Target as SignerProvider>::EcdsaSigner>), (Self, ChannelError)>
        where
                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) {
+               if !matches!(
+                       self.context.channel_state, ChannelState::NegotiatingFunding(flags)
+                       if flags == (NegotiatingFundingFlags::OUR_INIT_SENT | NegotiatingFundingFlags::THEIR_INIT_SENT)
+               ) {
                        // 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.
@@ -6650,10 +7354,10 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                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.
+               // check_funding_created_signature may fail.
                self.context.holder_signer.as_mut().provide_channel_parameters(&self.context.channel_transaction_parameters);
 
-               let (counterparty_initial_commitment_tx, initial_commitment_tx, signature) = match self.funding_created_signature(&msg.signature, logger) {
+               let initial_commitment_tx = match self.check_funding_created_signature(&msg.signature, logger) {
                        Ok(res) => res,
                        Err(ChannelError::Close(e)) => {
                                self.context.channel_transaction_parameters.funding_outpoint = None;
@@ -6662,7 +7366,7 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                        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);
+                               panic!("unexpected error type from check_funding_created_signature {:?}", e);
                        }
                };
 
@@ -6680,6 +7384,13 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
 
                // Now that we're past error-generating stuff, update our local state:
 
+               self.context.channel_state = ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::new());
+               self.context.channel_id = ChannelId::v1_from_funding_outpoint(funding_txo);
+               self.context.cur_counterparty_commitment_transaction_number -= 1;
+               self.context.cur_holder_commitment_transaction_number -= 1;
+
+               let (counterparty_initial_commitment_tx, funding_signed) = self.context.get_funding_signed_msg(logger);
+
                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());
@@ -6692,42 +7403,31 @@ impl<SP: Deref> InboundV1Channel<SP> where SP::Target: SignerProvider {
                                                          &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);
-
+                                                         holder_commitment_tx, best_block, self.context.counterparty_node_id, self.context.channel_id());
                channel_monitor.provide_initial_counterparty_commitment_tx(
                        counterparty_initial_commitment_tx.trust().txid(), Vec::new(),
-                       self.context.cur_counterparty_commitment_transaction_number,
+                       self.context.cur_counterparty_commitment_transaction_number + 1,
                        self.context.counterparty_cur_commitment_point.unwrap(), self.context.feerate_per_kw,
                        counterparty_initial_commitment_tx.to_broadcaster_value_sat(),
                        counterparty_initial_commitment_tx.to_countersignatory_value_sat(), 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 {}", &self.context.channel_id());
+               log_info!(logger, "{} funding_signed for peer for channel {}",
+                       if funding_signed.is_some() { "Generated" } else { "Waiting for signature on" }, &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))
+               Ok((channel, funding_signed, channel_monitor))
        }
 }
 
 const SERIALIZATION_VERSION: u8 = 3;
-const MIN_SERIALIZATION_VERSION: u8 = 2;
+const MIN_SERIALIZATION_VERSION: u8 = 3;
 
 impl_writeable_tlv_based_enum!(InboundHTLCRemovalReason,;
        (0, FailRelay),
@@ -6802,19 +7502,19 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
                writer.write_all(&[0; 8])?;
 
                self.context.channel_id.write(writer)?;
-               (self.context.channel_state | ChannelState::PeerDisconnected as u32).write(writer)?;
+               {
+                       let mut channel_state = self.context.channel_state;
+                       if matches!(channel_state, ChannelState::AwaitingChannelReady(_)|ChannelState::ChannelReady(_)) {
+                               channel_state.set_peer_disconnected();
+                       } else {
+                               debug_assert!(false, "Pre-funded/shutdown channels should not be written");
+                       }
+                       channel_state.to_u32().write(writer)?;
+               }
                self.context.channel_value_satoshis.write(writer)?;
 
                self.context.latest_monitor_update_id.write(writer)?;
 
-               let mut key_data = VecWriter(Vec::new());
-               // TODO (taproot|arik): Introduce serialization distinction for non-ECDSA signers.
-               self.context.holder_signer.as_ecdsa().expect("Only ECDSA signers may be serialized").write(&mut key_data)?;
-               assert!(key_data.0.len() < core::usize::MAX);
-               assert!(key_data.0.len() < core::u32::MAX as usize);
-               (key_data.0.len() as u32).write(writer)?;
-               writer.write_all(&key_data.0[..])?;
-
                // Write out the old serialization for shutdown_pubkey for backwards compatibility, if
                // deserialized from that format.
                match self.context.shutdown_scriptpubkey.as_ref().and_then(|script| script.as_legacy_pubkey()) {
@@ -6864,9 +7564,10 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
 
                let mut preimages: Vec<&Option<PaymentPreimage>> = vec![];
                let mut pending_outbound_skimmed_fees: Vec<Option<u64>> = Vec::new();
+               let mut pending_outbound_blinding_points: Vec<Option<PublicKey>> = Vec::new();
 
                (self.context.pending_outbound_htlcs.len() as u64).write(writer)?;
-               for (idx, htlc) in self.context.pending_outbound_htlcs.iter().enumerate() {
+               for htlc in self.context.pending_outbound_htlcs.iter() {
                        htlc.htlc_id.write(writer)?;
                        htlc.amount_msat.write(writer)?;
                        htlc.cltv_expiry.write(writer)?;
@@ -6902,23 +7603,20 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
                                        reason.write(writer)?;
                                }
                        }
-                       if let Some(skimmed_fee) = htlc.skimmed_fee_msat {
-                               if pending_outbound_skimmed_fees.is_empty() {
-                                       for _ in 0..idx { pending_outbound_skimmed_fees.push(None); }
-                               }
-                               pending_outbound_skimmed_fees.push(Some(skimmed_fee));
-                       } else if !pending_outbound_skimmed_fees.is_empty() {
-                               pending_outbound_skimmed_fees.push(None);
-                       }
+                       pending_outbound_skimmed_fees.push(htlc.skimmed_fee_msat);
+                       pending_outbound_blinding_points.push(htlc.blinding_point);
                }
 
                let mut holding_cell_skimmed_fees: Vec<Option<u64>> = Vec::new();
+               let mut holding_cell_blinding_points: Vec<Option<PublicKey>> = Vec::new();
+               // Vec of (htlc_id, failure_code, sha256_of_onion)
+               let mut malformed_htlcs: Vec<(u64, u16, [u8; 32])> = Vec::new();
                (self.context.holding_cell_htlc_updates.len() as u64).write(writer)?;
-               for (idx, update) in self.context.holding_cell_htlc_updates.iter().enumerate() {
+               for update in self.context.holding_cell_htlc_updates.iter() {
                        match update {
                                &HTLCUpdateAwaitingACK::AddHTLC {
                                        ref amount_msat, ref cltv_expiry, ref payment_hash, ref source, ref onion_routing_packet,
-                                       skimmed_fee_msat,
+                                       blinding_point, skimmed_fee_msat,
                                } => {
                                        0u8.write(writer)?;
                                        amount_msat.write(writer)?;
@@ -6927,12 +7625,8 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
                                        source.write(writer)?;
                                        onion_routing_packet.write(writer)?;
 
-                                       if let Some(skimmed_fee) = skimmed_fee_msat {
-                                               if holding_cell_skimmed_fees.is_empty() {
-                                                       for _ in 0..idx { holding_cell_skimmed_fees.push(None); }
-                                               }
-                                               holding_cell_skimmed_fees.push(Some(skimmed_fee));
-                                       } else if !holding_cell_skimmed_fees.is_empty() { holding_cell_skimmed_fees.push(None); }
+                                       holding_cell_skimmed_fees.push(skimmed_fee_msat);
+                                       holding_cell_blinding_points.push(blinding_point);
                                },
                                &HTLCUpdateAwaitingACK::ClaimHTLC { ref payment_preimage, ref htlc_id } => {
                                        1u8.write(writer)?;
@@ -6944,6 +7638,18 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
                                        htlc_id.write(writer)?;
                                        err_packet.write(writer)?;
                                }
+                               &HTLCUpdateAwaitingACK::FailMalformedHTLC {
+                                       htlc_id, failure_code, sha256_of_onion
+                               } => {
+                                       // We don't want to break downgrading by adding a new variant, so write a dummy
+                                       // `::FailHTLC` variant and write the real malformed error as an optional TLV.
+                                       malformed_htlcs.push((htlc_id, failure_code, sha256_of_onion));
+
+                                       let dummy_err_packet = msgs::OnionErrorPacket { data: Vec::new() };
+                                       2u8.write(writer)?;
+                                       htlc_id.write(writer)?;
+                                       dummy_err_packet.write(writer)?;
+                               }
                        }
                }
 
@@ -7102,6 +7808,9 @@ impl<SP: Deref> Writeable for Channel<SP> where SP::Target: SignerProvider {
                        (35, pending_outbound_skimmed_fees, optional_vec),
                        (37, holding_cell_skimmed_fees, optional_vec),
                        (38, self.context.is_batch_funding, option),
+                       (39, pending_outbound_blinding_points, optional_vec),
+                       (41, holding_cell_blinding_points, optional_vec),
+                       (43, malformed_htlcs, optional_vec), // Added in 0.0.119
                });
 
                Ok(())
@@ -7136,7 +7845,7 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                }
 
                let channel_id = Readable::read(reader)?;
-               let channel_state = Readable::read(reader)?;
+               let channel_state = ChannelState::from_u32(Readable::read(reader)?).map_err(|_| DecodeError::InvalidValue)?;
                let channel_value_satoshis = Readable::read(reader)?;
 
                let latest_monitor_update_id = Readable::read(reader)?;
@@ -7213,6 +7922,7 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                                        _ => return Err(DecodeError::InvalidValue),
                                },
                                skimmed_fee_msat: None,
+                               blinding_point: None,
                        });
                }
 
@@ -7227,6 +7937,7 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                                        source: Readable::read(reader)?,
                                        onion_routing_packet: Readable::read(reader)?,
                                        skimmed_fee_msat: None,
+                                       blinding_point: None,
                                },
                                1 => HTLCUpdateAwaitingACK::ClaimHTLC {
                                        payment_preimage: Readable::read(reader)?,
@@ -7387,6 +8098,11 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
 
                let mut is_batch_funding: Option<()> = None;
 
+               let mut pending_outbound_blinding_points_opt: Option<Vec<Option<PublicKey>>> = None;
+               let mut holding_cell_blinding_points_opt: Option<Vec<Option<PublicKey>>> = None;
+
+               let mut malformed_htlcs: Option<Vec<(u64, u16, [u8; 32])>> = None;
+
                read_tlv_fields!(reader, {
                        (0, announcement_sigs, option),
                        (1, minimum_depth, option),
@@ -7413,14 +8129,16 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                        (35, pending_outbound_skimmed_fees_opt, optional_vec),
                        (37, holding_cell_skimmed_fees_opt, optional_vec),
                        (38, is_batch_funding, option),
+                       (39, pending_outbound_blinding_points_opt, optional_vec),
+                       (41, holding_cell_blinding_points_opt, optional_vec),
+                       (43, malformed_htlcs, optional_vec), // Added in 0.0.119
                });
 
                let (channel_keys_id, holder_signer) = if let Some(channel_keys_id) = channel_keys_id {
                        let mut holder_signer = signer_provider.derive_channel_signer(channel_value_satoshis, channel_keys_id);
                        // If we've gotten to the funding stage of the channel, populate the signer with its
                        // required channel parameters.
-                       let non_shutdown_state = channel_state & (!MULTI_STATE_FLAGS);
-                       if non_shutdown_state & !STATE_FLAGS >= (ChannelState::FundingCreated as u32) {
+                       if channel_state >= ChannelState::FundingNegotiated {
                                holder_signer.provide_channel_parameters(&channel_parameters);
                        }
                        (channel_keys_id, holder_signer)
@@ -7489,6 +8207,40 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                        // We expect all skimmed fees to be consumed above
                        if iter.next().is_some() { return Err(DecodeError::InvalidValue) }
                }
+               if let Some(blinding_pts) = pending_outbound_blinding_points_opt {
+                       let mut iter = blinding_pts.into_iter();
+                       for htlc in pending_outbound_htlcs.iter_mut() {
+                               htlc.blinding_point = iter.next().ok_or(DecodeError::InvalidValue)?;
+                       }
+                       // We expect all blinding points to be consumed above
+                       if iter.next().is_some() { return Err(DecodeError::InvalidValue) }
+               }
+               if let Some(blinding_pts) = holding_cell_blinding_points_opt {
+                       let mut iter = blinding_pts.into_iter();
+                       for htlc in holding_cell_htlc_updates.iter_mut() {
+                               if let HTLCUpdateAwaitingACK::AddHTLC { ref mut blinding_point, .. } = htlc {
+                                       *blinding_point = iter.next().ok_or(DecodeError::InvalidValue)?;
+                               }
+                       }
+                       // We expect all blinding points to be consumed above
+                       if iter.next().is_some() { return Err(DecodeError::InvalidValue) }
+               }
+
+               if let Some(malformed_htlcs) = malformed_htlcs {
+                       for (malformed_htlc_id, failure_code, sha256_of_onion) in malformed_htlcs {
+                               let htlc_idx = holding_cell_htlc_updates.iter().position(|htlc| {
+                                       if let HTLCUpdateAwaitingACK::FailHTLC { htlc_id, err_packet } = htlc {
+                                               let matches = *htlc_id == malformed_htlc_id;
+                                               if matches { debug_assert!(err_packet.data.is_empty()) }
+                                               matches
+                                       } else { false }
+                               }).ok_or(DecodeError::InvalidValue)?;
+                               let malformed_htlc = HTLCUpdateAwaitingACK::FailMalformedHTLC {
+                                       htlc_id: malformed_htlc_id, failure_code, sha256_of_onion
+                               };
+                               let _ = core::mem::replace(&mut holding_cell_htlc_updates[htlc_idx], malformed_htlc);
+                       }
+               }
 
                Ok(Channel {
                        context: ChannelContext {
@@ -7533,6 +8285,9 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
                                monitor_pending_failures,
                                monitor_pending_finalized_fulfills: monitor_pending_finalized_fulfills.unwrap(),
 
+                               signer_pending_commitment_update: false,
+                               signer_pending_funding: false,
+
                                pending_update_fee,
                                holding_cell_update_fee,
                                next_holder_htlc_id,
@@ -7547,6 +8302,7 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
 
                                last_sent_closing_fee: None,
                                pending_counterparty_closing_signed: None,
+                               expecting_peer_commitment_signed: false,
                                closing_fee_limits: None,
                                target_closing_feerate_sats_per_kw,
 
@@ -7615,29 +8371,31 @@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> ReadableArgs<(&'a ES, &'b SP, u32, &'c Ch
 #[cfg(test)]
 mod tests {
        use std::cmp;
-       use bitcoin::blockdata::script::{Script, Builder};
+       use bitcoin::blockdata::constants::ChainHash;
+       use bitcoin::blockdata::script::{ScriptBuf, Builder};
        use bitcoin::blockdata::transaction::{Transaction, TxOut};
-       use bitcoin::blockdata::constants::genesis_block;
        use bitcoin::blockdata::opcodes;
        use bitcoin::network::constants::Network;
-       use hex;
-       use crate::ln::PaymentHash;
+       use crate::ln::onion_utils::INVALID_ONION_BLINDING;
+       use crate::ln::{PaymentHash, PaymentPreimage};
+       use crate::ln::channel_keys::{RevocationKey, RevocationBasepoint};
        use crate::ln::channelmanager::{self, HTLCSource, PaymentId};
        use crate::ln::channel::InitFeatures;
-       use crate::ln::channel::{Channel, ChannelState, InboundHTLCOutput, OutboundV1Channel, InboundV1Channel, OutboundHTLCOutput, InboundHTLCState, OutboundHTLCState, HTLCCandidate, HTLCInitiator, commit_tx_fee_msat};
+       use crate::ln::channel::{AwaitingChannelReadyFlags, Channel, ChannelState, InboundHTLCOutput, OutboundV1Channel, InboundV1Channel, OutboundHTLCOutput, InboundHTLCState, OutboundHTLCState, HTLCCandidate, HTLCInitiator, HTLCUpdateAwaitingACK, commit_tx_fee_msat};
        use crate::ln::channel::{MAX_FUNDING_SATOSHIS_NO_WUMBO, TOTAL_BITCOIN_SUPPLY_SATOSHIS, MIN_THEIR_CHAN_RESERVE_SATOSHIS};
-       use crate::ln::features::ChannelTypeFeatures;
+       use crate::ln::features::{ChannelFeatures, ChannelTypeFeatures, NodeFeatures};
+       use crate::ln::msgs;
        use crate::ln::msgs::{ChannelUpdate, DecodeError, UnsignedChannelUpdate, MAX_VALUE_MSAT};
        use crate::ln::script::ShutdownScript;
-       use crate::ln::chan_utils;
-       use crate::ln::chan_utils::{htlc_success_tx_weight, htlc_timeout_tx_weight};
+       use crate::ln::chan_utils::{self, htlc_success_tx_weight, htlc_timeout_tx_weight};
        use crate::chain::BestBlock;
        use crate::chain::chaininterface::{FeeEstimator, LowerBoundedFeeEstimator, ConfirmationTarget};
        use crate::sign::{ChannelSigner, InMemorySigner, EntropySource, SignerProvider};
        use crate::chain::transaction::OutPoint;
-       use crate::routing::router::Path;
+       use crate::routing::router::{Path, RouteHop};
        use crate::util::config::UserConfig;
        use crate::util::errors::APIError;
+       use crate::util::ser::{ReadableArgs, Writeable};
        use crate::util::test_utils;
        use crate::util::test_utils::{OnGetShutdownScriptpubkey, TestKeysInterface};
        use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
@@ -7645,11 +8403,24 @@ mod tests {
        use bitcoin::secp256k1::{SecretKey,PublicKey};
        use bitcoin::hashes::sha256::Hash as Sha256;
        use bitcoin::hashes::Hash;
+       use bitcoin::hashes::hex::FromHex;
        use bitcoin::hash_types::WPubkeyHash;
-       use bitcoin::PackedLockTime;
-       use bitcoin::util::address::WitnessVersion;
+       use bitcoin::blockdata::locktime::absolute::LockTime;
+       use bitcoin::address::{WitnessProgram, WitnessVersion};
        use crate::prelude::*;
 
+       #[test]
+       fn test_channel_state_order() {
+               use crate::ln::channel::NegotiatingFundingFlags;
+               use crate::ln::channel::AwaitingChannelReadyFlags;
+               use crate::ln::channel::ChannelReadyFlags;
+
+               assert!(ChannelState::NegotiatingFunding(NegotiatingFundingFlags::new()) < ChannelState::FundingNegotiated);
+               assert!(ChannelState::FundingNegotiated < ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::new()));
+               assert!(ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::new()) < ChannelState::ChannelReady(ChannelReadyFlags::new()));
+               assert!(ChannelState::ChannelReady(ChannelReadyFlags::new()) < ChannelState::ShutdownComplete);
+       }
+
        struct TestFeeEstimator {
                fee_est: u32
        }
@@ -7666,17 +8437,6 @@ mod tests {
                        "MAX_FUNDING_SATOSHIS_NO_WUMBO is greater than all satoshis in existence");
        }
 
-       #[test]
-       fn test_no_fee_check_overflow() {
-               // Previously, calling `check_remote_fee` with a fee of 0xffffffff would overflow in
-               // arithmetic, causing a panic with debug assertions enabled.
-               let fee_est = TestFeeEstimator { fee_est: 42 };
-               let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_est);
-               assert!(Channel::<&TestKeysInterface>::check_remote_fee(
-                       &ChannelTypeFeatures::only_static_remote_key(), &bounded_fee_estimator,
-                       u32::max_value(), None, &&test_utils::TestLogger::new()).is_err());
-       }
-
        struct Keys {
                signer: InMemorySigner,
        }
@@ -7686,42 +8446,45 @@ mod tests {
        }
 
        impl SignerProvider for Keys {
-               type Signer = InMemorySigner;
+               type EcdsaSigner = InMemorySigner;
+               #[cfg(taproot)]
+               type TaprootSigner = InMemorySigner;
 
                fn generate_channel_keys_id(&self, _inbound: bool, _channel_value_satoshis: u64, _user_channel_id: u128) -> [u8; 32] {
                        self.signer.channel_keys_id()
                }
 
-               fn derive_channel_signer(&self, _channel_value_satoshis: u64, _channel_keys_id: [u8; 32]) -> Self::Signer {
+               fn derive_channel_signer(&self, _channel_value_satoshis: u64, _channel_keys_id: [u8; 32]) -> Self::EcdsaSigner {
                        self.signer.clone()
                }
 
-               fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::Signer, DecodeError> { panic!(); }
+               fn read_chan_signer(&self, _data: &[u8]) -> Result<Self::EcdsaSigner, DecodeError> { panic!(); }
 
-               fn get_destination_script(&self) -> Result<Script, ()> {
+               fn get_destination_script(&self, _channel_keys_id: [u8; 32]) -> Result<ScriptBuf, ()> {
                        let secp_ctx = Secp256k1::signing_only();
-                       let channel_monitor_claim_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
+                       let channel_monitor_claim_key = SecretKey::from_slice(&<Vec<u8>>::from_hex("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
                        let channel_monitor_claim_key_hash = WPubkeyHash::hash(&PublicKey::from_secret_key(&secp_ctx, &channel_monitor_claim_key).serialize());
-                       Ok(Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&channel_monitor_claim_key_hash[..]).into_script())
+                       Ok(Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(channel_monitor_claim_key_hash).into_script())
                }
 
                fn get_shutdown_scriptpubkey(&self) -> Result<ShutdownScript, ()> {
                        let secp_ctx = Secp256k1::signing_only();
-                       let channel_close_key = SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
+                       let channel_close_key = SecretKey::from_slice(&<Vec<u8>>::from_hex("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap();
                        Ok(ShutdownScript::new_p2wpkh_from_pubkey(PublicKey::from_secret_key(&secp_ctx, &channel_close_key)))
                }
        }
 
        #[cfg(all(feature = "_test_vectors", not(feature = "grind_signatures")))]
        fn public_from_secret_hex(secp_ctx: &Secp256k1<bitcoin::secp256k1::All>, hex: &str) -> PublicKey {
-               PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&hex::decode(hex).unwrap()[..]).unwrap())
+               PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&<Vec<u8>>::from_hex(hex).unwrap()[..]).unwrap())
        }
 
        #[test]
        fn upfront_shutdown_script_incompatibility() {
                let features = channelmanager::provided_init_features(&UserConfig::default()).clear_shutdown_anysegwit();
-               let non_v0_segwit_shutdown_script =
-                       ShutdownScript::new_witness_program(WitnessVersion::V16, &[0, 40]).unwrap();
+               let non_v0_segwit_shutdown_script = ShutdownScript::new_witness_program(
+                       &WitnessProgram::new(WitnessVersion::V16, &[0, 40]).unwrap(),
+               ).unwrap();
 
                let seed = [42; 32];
                let network = Network::Testnet;
@@ -7733,7 +8496,7 @@ 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::<&TestKeysInterface>::new(&LowerBoundedFeeEstimator::new(&TestFeeEstimator { fee_est: 253 }), &&keys_provider, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0, 42) {
+               match OutboundV1Channel::<&TestKeysInterface>::new(&LowerBoundedFeeEstimator::new(&TestFeeEstimator { fee_est: 253 }), &&keys_provider, &&keys_provider, node_id, &features, 10000000, 100000, 42, &config, 0, 42, None) {
                        Err(APIError::IncompatibleShutdownScript { script }) => {
                                assert_eq!(script.into_inner(), non_v0_segwit_shutdown_script.into_inner());
                        },
@@ -7756,12 +8519,12 @@ 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::<&TestKeysInterface>::new(&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::<&TestKeysInterface>::new(&bounded_fee_estimator, &&keys_provider, &&keys_provider, node_a_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).unwrap();
 
                // Now change the fee so we can check that the fee in the open_channel message is the
                // same as the old fee.
                fee_est.fee_est = 500;
-               let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
+               let open_channel_msg = node_a_chan.get_open_channel(ChainHash::using_genesis_block(network));
                assert_eq!(open_channel_msg.feerate_per_kw, original_fee);
        }
 
@@ -7783,11 +8546,11 @@ 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::<&TestKeysInterface>::new(&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::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).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 open_channel_msg = node_a_chan.get_open_channel(ChainHash::using_genesis_block(network));
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
                let mut node_b_chan = InboundV1Channel::<&TestKeysInterface>::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, /*is_0conf=*/false).unwrap();
 
@@ -7799,22 +8562,23 @@ mod tests {
 
                // 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 {
+               let tx = Transaction { version: 1, lock_time: LockTime::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_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap();
-               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).map_err(|_| ()).unwrap();
+               let funding_created_msg = node_a_chan.get_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap();
+               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg.unwrap(), 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();
+               let res = node_a_chan.funding_signed(&funding_signed_msg.unwrap(), best_block, &&keys_provider, &&logger);
+               let (mut node_a_chan, _) = if let Ok(res) = res { res } else { panic!(); };
 
                // 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 {
                        htlc_id: 0,
                        amount_msat: htlc_amount_msat,
-                       payment_hash: PaymentHash(Sha256::hash(&[42; 32]).into_inner()),
+                       payment_hash: PaymentHash(Sha256::hash(&[42; 32]).to_byte_array()),
                        cltv_expiry: 300000000,
                        state: InboundHTLCState::Committed,
                });
@@ -7822,16 +8586,17 @@ mod tests {
                node_a_chan.context.pending_outbound_htlcs.push(OutboundHTLCOutput {
                        htlc_id: 1,
                        amount_msat: htlc_amount_msat, // put an amount below A's dust amount but above B's.
-                       payment_hash: PaymentHash(Sha256::hash(&[43; 32]).into_inner()),
+                       payment_hash: PaymentHash(Sha256::hash(&[43; 32]).to_byte_array()),
                        cltv_expiry: 200000000,
                        state: OutboundHTLCState::Committed,
                        source: HTLCSource::OutboundRoute {
                                path: Path { hops: Vec::new(), blinded_tail: None },
-                               session_priv: SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
+                               session_priv: SecretKey::from_slice(&<Vec<u8>>::from_hex("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
                                first_hop_htlc_msat: 548,
                                payment_id: PaymentId([42; 32]),
                        },
                        skimmed_fee_msat: None,
+                       blinding_point: None,
                });
 
                // Make sure when Node A calculates their local commitment transaction, none of the HTLCs pass
@@ -7864,7 +8629,7 @@ 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::<&TestKeysInterface>::new(&fee_est, &&keys_provider, &&keys_provider, node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+               let mut chan = OutboundV1Channel::<&TestKeysInterface>::new(&fee_est, &&keys_provider, &&keys_provider, node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).unwrap();
 
                let commitment_tx_fee_0_htlcs = commit_tx_fee_msat(chan.context.feerate_per_kw, 0, chan.context.get_channel_type());
                let commitment_tx_fee_1_htlc = commit_tx_fee_msat(chan.context.feerate_per_kw, 1, chan.context.get_channel_type());
@@ -7905,7 +8670,7 @@ mod tests {
                let seed = [42; 32];
                let network = Network::Testnet;
                let best_block = BestBlock::from_network(network);
-               let chain_hash = best_block.block_hash();
+               let chain_hash = ChainHash::using_genesis_block(network);
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
 
                // Go through the flow of opening a channel between two nodes.
@@ -7913,7 +8678,7 @@ 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::<&TestKeysInterface>::new(&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::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).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);
@@ -7926,15 +8691,16 @@ mod tests {
 
                // 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 {
+               let tx = Transaction { version: 1, lock_time: LockTime::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_funding_created(tx.clone(), funding_outpoint, false, &&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();
+               let funding_created_msg = node_a_chan.get_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap();
+               let (mut node_b_chan, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg.unwrap(), 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();
+               let res = node_a_chan.funding_signed(&funding_signed_msg.unwrap(), best_block, &&keys_provider, &&logger);
+               let (mut node_a_chan, _) = if let Ok(res) = res { res } else { panic!(); };
 
                // Now disconnect the two nodes and check that the commitment point in
                // Node B's channel_reestablish message is sane.
@@ -7976,16 +8742,16 @@ mod tests {
                // 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::<&TestKeysInterface>::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 = OutboundV1Channel::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_2_percent), 10000000, 100000, 42, &config_2_percent, 0, 42, None).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::<&TestKeysInterface>::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 = OutboundV1Channel::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_99_percent), 10000000, 100000, 42, &config_99_percent, 0, 42, None).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());
+               let chan_1_open_channel_msg = chan_1.get_open_channel(ChainHash::using_genesis_block(network));
 
                // 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,
@@ -8001,14 +8767,14 @@ mod tests {
 
                // 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::<&TestKeysInterface>::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 = OutboundV1Channel::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_0_percent), 10000000, 100000, 42, &config_0_percent, 0, 42, None).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 `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::<&TestKeysInterface>::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 = OutboundV1Channel::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, outbound_node_id, &channelmanager::provided_init_features(&config_101_percent), 10000000, 100000, 42, &config_101_percent, 0, 42, None).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);
 
@@ -8061,12 +8827,12 @@ 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::<&TestKeysInterface>::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 chan = OutboundV1Channel::<&TestKeysInterface>::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, None).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);
 
-               let chan_open_channel_msg = chan.get_open_channel(genesis_block(network).header.block_hash());
+               let chan_open_channel_msg = chan.get_open_channel(ChainHash::using_genesis_block(network));
                let mut inbound_node_config = UserConfig::default();
                inbound_node_config.channel_handshake_config.their_channel_reserve_proportional_millionths = (inbound_selected_channel_reserve_perc * 1_000_000.0) as u32;
 
@@ -8092,17 +8858,17 @@ mod tests {
                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 chain_hash = ChainHash::using_genesis_block(network);
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
 
                // 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::<&TestKeysInterface>::new(&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::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).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 open_channel_msg = node_a_chan.get_open_channel(ChainHash::using_genesis_block(network));
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
                let mut node_b_chan = InboundV1Channel::<&TestKeysInterface>::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, /*is_0conf=*/false).unwrap();
 
@@ -8114,15 +8880,16 @@ mod tests {
 
                // 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 {
+               let tx = Transaction { version: 1, lock_time: LockTime::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_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap();
-               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg, best_block, &&keys_provider, &&logger).map_err(|_| ()).unwrap();
+               let funding_created_msg = node_a_chan.get_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap();
+               let (_, funding_signed_msg, _) = node_b_chan.funding_created(&funding_created_msg.unwrap(), 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();
+               let res = node_a_chan.funding_signed(&funding_signed_msg.unwrap(), best_block, &&keys_provider, &&logger);
+               let (mut node_a_chan, _) = if let Ok(res) = res { res } else { panic!(); };
 
                // Make sure that receiving a channel update will update the Channel as expected.
                let update = ChannelUpdate {
@@ -8140,7 +8907,7 @@ mod tests {
                        },
                        signature: Signature::from(unsafe { FFISignature::new() })
                };
-               node_a_chan.channel_update(&update).unwrap();
+               assert!(node_a_chan.channel_update(&update).unwrap());
 
                // The counterparty can send an update with a higher minimum HTLC, but that shouldn't
                // change our official htlc_minimum_msat.
@@ -8153,36 +8920,165 @@ mod tests {
                        },
                        None => panic!("expected counterparty forwarding info to be Some")
                }
+
+               assert!(!node_a_chan.channel_update(&update).unwrap());
+       }
+
+       #[test]
+       fn blinding_point_skimmed_fee_malformed_ser() {
+               // Ensure that channel blinding points, skimmed fees, and malformed HTLCs are (de)serialized
+               // properly.
+               let logger = test_utils::TestLogger::new();
+               let feeest = LowerBoundedFeeEstimator::new(&TestFeeEstimator{fee_est: 15000});
+               let secp_ctx = Secp256k1::new();
+               let seed = [42; 32];
+               let network = Network::Testnet;
+               let best_block = BestBlock::from_network(network);
+               let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
+
+               let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
+               let config = UserConfig::default();
+               let features = channelmanager::provided_init_features(&config);
+               let mut outbound_chan = OutboundV1Channel::<&TestKeysInterface>::new(
+                       &feeest, &&keys_provider, &&keys_provider, node_b_node_id, &features, 10000000, 100000, 42, &config, 0, 42, None
+               ).unwrap();
+               let inbound_chan = InboundV1Channel::<&TestKeysInterface>::new(
+                       &feeest, &&keys_provider, &&keys_provider, node_b_node_id, &channelmanager::provided_channel_type_features(&config),
+                       &features, &outbound_chan.get_open_channel(ChainHash::using_genesis_block(network)), 7, &config, 0, &&logger, false
+               ).unwrap();
+               outbound_chan.accept_channel(&inbound_chan.get_accept_channel_message(), &config.channel_handshake_limits, &features).unwrap();
+               let tx = Transaction { version: 1, lock_time: LockTime::ZERO, input: Vec::new(), output: vec![TxOut {
+                       value: 10000000, script_pubkey: outbound_chan.context.get_funding_redeemscript(),
+               }]};
+               let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
+               let funding_created = outbound_chan.get_funding_created(tx.clone(), funding_outpoint, false, &&logger).map_err(|_| ()).unwrap().unwrap();
+               let mut chan = match inbound_chan.funding_created(&funding_created, best_block, &&keys_provider, &&logger) {
+                       Ok((chan, _, _)) => chan,
+                       Err((_, e)) => panic!("{}", e),
+               };
+
+               let dummy_htlc_source = HTLCSource::OutboundRoute {
+                       path: Path {
+                               hops: vec![RouteHop {
+                                       pubkey: test_utils::pubkey(2), channel_features: ChannelFeatures::empty(),
+                                       node_features: NodeFeatures::empty(), short_channel_id: 0, fee_msat: 0,
+                                       cltv_expiry_delta: 0, maybe_announced_channel: false,
+                               }],
+                               blinded_tail: None
+                       },
+                       session_priv: test_utils::privkey(42),
+                       first_hop_htlc_msat: 0,
+                       payment_id: PaymentId([42; 32]),
+               };
+               let dummy_outbound_output = OutboundHTLCOutput {
+                       htlc_id: 0,
+                       amount_msat: 0,
+                       payment_hash: PaymentHash([43; 32]),
+                       cltv_expiry: 0,
+                       state: OutboundHTLCState::Committed,
+                       source: dummy_htlc_source.clone(),
+                       skimmed_fee_msat: None,
+                       blinding_point: None,
+               };
+               let mut pending_outbound_htlcs = vec![dummy_outbound_output.clone(); 10];
+               for (idx, htlc) in pending_outbound_htlcs.iter_mut().enumerate() {
+                       if idx % 2 == 0 {
+                               htlc.blinding_point = Some(test_utils::pubkey(42 + idx as u8));
+                       }
+                       if idx % 3 == 0 {
+                               htlc.skimmed_fee_msat = Some(1);
+                       }
+               }
+               chan.context.pending_outbound_htlcs = pending_outbound_htlcs.clone();
+
+               let dummy_holding_cell_add_htlc = HTLCUpdateAwaitingACK::AddHTLC {
+                       amount_msat: 0,
+                       cltv_expiry: 0,
+                       payment_hash: PaymentHash([43; 32]),
+                       source: dummy_htlc_source.clone(),
+                       onion_routing_packet: msgs::OnionPacket {
+                               version: 0,
+                               public_key: Ok(test_utils::pubkey(1)),
+                               hop_data: [0; 20*65],
+                               hmac: [0; 32]
+                       },
+                       skimmed_fee_msat: None,
+                       blinding_point: None,
+               };
+               let dummy_holding_cell_claim_htlc = HTLCUpdateAwaitingACK::ClaimHTLC {
+                       payment_preimage: PaymentPreimage([42; 32]),
+                       htlc_id: 0,
+               };
+               let dummy_holding_cell_failed_htlc = |htlc_id| HTLCUpdateAwaitingACK::FailHTLC {
+                       htlc_id, err_packet: msgs::OnionErrorPacket { data: vec![42] }
+               };
+               let dummy_holding_cell_malformed_htlc = |htlc_id| HTLCUpdateAwaitingACK::FailMalformedHTLC {
+                       htlc_id, failure_code: INVALID_ONION_BLINDING, sha256_of_onion: [0; 32],
+               };
+               let mut holding_cell_htlc_updates = Vec::with_capacity(12);
+               for i in 0..12 {
+                       if i % 5 == 0 {
+                               holding_cell_htlc_updates.push(dummy_holding_cell_add_htlc.clone());
+                       } else if i % 5 == 1 {
+                               holding_cell_htlc_updates.push(dummy_holding_cell_claim_htlc.clone());
+                       } else if i % 5 == 2 {
+                               let mut dummy_add = dummy_holding_cell_add_htlc.clone();
+                               if let HTLCUpdateAwaitingACK::AddHTLC {
+                                       ref mut blinding_point, ref mut skimmed_fee_msat, ..
+                               } = &mut dummy_add {
+                                       *blinding_point = Some(test_utils::pubkey(42 + i));
+                                       *skimmed_fee_msat = Some(42);
+                               } else { panic!() }
+                               holding_cell_htlc_updates.push(dummy_add);
+                       } else if i % 5 == 3 {
+                               holding_cell_htlc_updates.push(dummy_holding_cell_malformed_htlc(i as u64));
+                       } else {
+                               holding_cell_htlc_updates.push(dummy_holding_cell_failed_htlc(i as u64));
+                       }
+               }
+               chan.context.holding_cell_htlc_updates = holding_cell_htlc_updates.clone();
+
+               // Encode and decode the channel and ensure that the HTLCs within are the same.
+               let encoded_chan = chan.encode();
+               let mut s = crate::io::Cursor::new(&encoded_chan);
+               let mut reader = crate::util::ser::FixedLengthReader::new(&mut s, encoded_chan.len() as u64);
+               let features = channelmanager::provided_channel_type_features(&config);
+               let decoded_chan = Channel::read(&mut reader, (&&keys_provider, &&keys_provider, 0, &features)).unwrap();
+               assert_eq!(decoded_chan.context.pending_outbound_htlcs, pending_outbound_htlcs);
+               assert_eq!(decoded_chan.context.holding_cell_htlc_updates, holding_cell_htlc_updates);
        }
 
-       #[cfg(feature = "_test_vectors")]
+       #[cfg(all(feature = "_test_vectors", not(feature = "grind_signatures")))]
        #[test]
        fn outbound_commitment_test() {
-               use bitcoin::util::sighash;
+               use bitcoin::sighash;
                use bitcoin::consensus::encode::serialize;
-               use bitcoin::blockdata::transaction::EcdsaSighashType;
+               use bitcoin::sighash::EcdsaSighashType;
                use bitcoin::hashes::hex::FromHex;
                use bitcoin::hash_types::Txid;
                use bitcoin::secp256k1::Message;
-               use crate::sign::EcdsaChannelSigner;
+               use crate::sign::{ChannelDerivationParameters, HTLCDescriptor, ecdsa::EcdsaChannelSigner};
                use crate::ln::PaymentPreimage;
                use crate::ln::channel::{HTLCOutputInCommitment ,TxCreationKeys};
+               use crate::ln::channel_keys::{DelayedPaymentBasepoint, HtlcBasepoint};
                use crate::ln::chan_utils::{ChannelPublicKeys, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
                use crate::util::logger::Logger;
                use crate::sync::Arc;
+               use core::str::FromStr;
+               use hex::DisplayHex;
 
                // Test vectors from BOLT 3 Appendices C and F (anchors):
                let feeest = TestFeeEstimator{fee_est: 15000};
-               let logger : Arc<Logger> = Arc::new(test_utils::TestLogger::new());
+               let logger : Arc<dyn Logger> = Arc::new(test_utils::TestLogger::new());
                let secp_ctx = Secp256k1::new();
 
                let mut signer = InMemorySigner::new(
                        &secp_ctx,
-                       SecretKey::from_slice(&hex::decode("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
-                       SecretKey::from_slice(&hex::decode("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
-                       SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
-                       SecretKey::from_slice(&hex::decode("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
-                       SecretKey::from_slice(&hex::decode("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
+                       SecretKey::from_slice(&<Vec<u8>>::from_hex("30ff4956bbdd3222d44cc5e8a1261dab1e07957bdac5ae88fe3261ef321f3749").unwrap()[..]).unwrap(),
+                       SecretKey::from_slice(&<Vec<u8>>::from_hex("0fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff").unwrap()[..]).unwrap(),
+                       SecretKey::from_slice(&<Vec<u8>>::from_hex("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
+                       SecretKey::from_slice(&<Vec<u8>>::from_hex("3333333333333333333333333333333333333333333333333333333333333333").unwrap()[..]).unwrap(),
+                       SecretKey::from_slice(&<Vec<u8>>::from_hex("1111111111111111111111111111111111111111111111111111111111111111").unwrap()[..]).unwrap(),
 
                        // These aren't set in the test vectors:
                        [0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff],
@@ -8192,24 +9088,24 @@ mod tests {
                );
 
                assert_eq!(signer.pubkeys().funding_pubkey.serialize()[..],
-                               hex::decode("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
+                               <Vec<u8>>::from_hex("023da092f6980e58d2c037173180e9a465476026ee50f96695963e8efe436f54eb").unwrap()[..]);
                let keys_provider = Keys { signer: signer.clone() };
 
                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 = OutboundV1Channel::<&Keys>::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
+               let mut chan = OutboundV1Channel::<&Keys>::new(&LowerBoundedFeeEstimator::new(&feeest), &&keys_provider, &&keys_provider, counterparty_node_id, &channelmanager::provided_init_features(&config), 10_000_000, 0, 42, &config, 0, 42, None).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
 
-               let funding_info = OutPoint{ txid: Txid::from_hex("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
+               let funding_info = OutPoint{ txid: Txid::from_str("8984484a580b825b9972d7adb15050b3ab624ccd731946b3eeddb92f4e7ef6be").unwrap(), index: 0 };
 
                let counterparty_pubkeys = ChannelPublicKeys {
                        funding_pubkey: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
-                       revocation_basepoint: PublicKey::from_slice(&hex::decode("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap(),
+                       revocation_basepoint: RevocationBasepoint::from(PublicKey::from_slice(&<Vec<u8>>::from_hex("02466d7fcae563e5cb09a0d1870bb580344804617879a14949cf22285f1bae3f27").unwrap()[..]).unwrap()),
                        payment_point: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"),
-                       delayed_payment_basepoint: public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13"),
-                       htlc_basepoint: public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444")
+                       delayed_payment_basepoint: DelayedPaymentBasepoint::from(public_from_secret_hex(&secp_ctx, "1552dfba4f6cf29a62a0af13c8d6981d36d0ef8d61ba10fb0fe90da7634d7e13")),
+                       htlc_basepoint: HtlcBasepoint::from(public_from_secret_hex(&secp_ctx, "4444444444444444444444444444444444444444444444444444444444444444"))
                };
                chan.context.channel_transaction_parameters.counterparty_parameters = Some(
                        CounterpartyChannelTransactionParameters {
@@ -8220,19 +9116,19 @@ mod tests {
                signer.provide_channel_parameters(&chan.context.channel_transaction_parameters);
 
                assert_eq!(counterparty_pubkeys.payment_point.serialize()[..],
-                          hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
+                          <Vec<u8>>::from_hex("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
 
                assert_eq!(counterparty_pubkeys.funding_pubkey.serialize()[..],
-                          hex::decode("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
+                          <Vec<u8>>::from_hex("030e9f7b623d2ccc7c9bd44d66d5ce21ce504c0acf6385a132cec6d3c39fa711c1").unwrap()[..]);
 
-               assert_eq!(counterparty_pubkeys.htlc_basepoint.serialize()[..],
-                          hex::decode("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
+               assert_eq!(counterparty_pubkeys.htlc_basepoint.to_public_key().serialize()[..],
+                          <Vec<u8>>::from_hex("032c0b7cf95324a07d05398b240174dc0c2be444d96b159aa6c7f7b1e668680991").unwrap()[..]);
 
                // We can't just use build_holder_transaction_keys here as the per_commitment_secret is not
                // derived from a commitment_seed, so instead we copy it here and call
                // build_commitment_transaction.
                let delayed_payment_base = &chan.context.holder_signer.as_ref().pubkeys().delayed_payment_basepoint;
-               let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
+               let per_commitment_secret = SecretKey::from_slice(&<Vec<u8>>::from_hex("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
                let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
                let htlc_basepoint = &chan.context.holder_signer.as_ref().pubkeys().htlc_basepoint;
                let keys = TxCreationKeys::derive_new(&secp_ctx, &per_commitment_point, delayed_payment_base, htlc_basepoint, &counterparty_pubkeys.revocation_basepoint, &counterparty_pubkeys.htlc_basepoint);
@@ -8266,9 +9162,9 @@ mod tests {
                                let trusted_tx = commitment_tx.trust();
                                let unsigned_tx = trusted_tx.built_transaction();
                                let redeemscript = chan.context.get_funding_redeemscript();
-                               let counterparty_signature = Signature::from_der(&hex::decode($counterparty_sig_hex).unwrap()[..]).unwrap();
+                               let counterparty_signature = Signature::from_der(&<Vec<u8>>::from_hex($counterparty_sig_hex).unwrap()[..]).unwrap();
                                let sighash = unsigned_tx.get_sighash_all(&redeemscript, chan.context.channel_value_satoshis);
-                               log_trace!(logger, "unsigned_tx = {}", hex::encode(serialize(&unsigned_tx.transaction)));
+                               log_trace!(logger, "unsigned_tx = {}", serialize(&unsigned_tx.transaction).as_hex());
                                assert!(secp_ctx.verify_ecdsa(&sighash, &counterparty_signature, chan.context.counterparty_funding_pubkey()).is_ok(), "verify counterparty commitment sig");
 
                                let mut per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>)> = Vec::new();
@@ -8276,7 +9172,7 @@ mod tests {
                                let mut counterparty_htlc_sigs = Vec::new();
                                counterparty_htlc_sigs.clear(); // Don't warn about excess mut for no-HTLC calls
                                $({
-                                       let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
+                                       let remote_signature = Signature::from_der(&<Vec<u8>>::from_hex($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
                                        per_htlc.push((htlcs[$htlc_idx].clone(), Some(remote_signature)));
                                        counterparty_htlc_sigs.push(remote_signature);
                                })*
@@ -8289,33 +9185,33 @@ mod tests {
                                        &chan.context.holder_signer.as_ref().pubkeys().funding_pubkey,
                                        chan.context.counterparty_funding_pubkey()
                                );
-                               let (holder_sig, htlc_sigs) = signer.sign_holder_commitment_and_htlcs(&holder_commitment_tx, &secp_ctx).unwrap();
-                               assert_eq!(Signature::from_der(&hex::decode($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
+                               let holder_sig = signer.sign_holder_commitment(&holder_commitment_tx, &secp_ctx).unwrap();
+                               assert_eq!(Signature::from_der(&<Vec<u8>>::from_hex($sig_hex).unwrap()[..]).unwrap(), holder_sig, "holder_sig");
 
                                let funding_redeemscript = chan.context.get_funding_redeemscript();
                                let tx = holder_commitment_tx.add_holder_sig(&funding_redeemscript, holder_sig);
-                               assert_eq!(serialize(&tx)[..], hex::decode($tx_hex).unwrap()[..], "tx");
+                               assert_eq!(serialize(&tx)[..], <Vec<u8>>::from_hex($tx_hex).unwrap()[..], "tx");
 
                                // ((htlc, counterparty_sig), (index, holder_sig))
-                               let mut htlc_sig_iter = holder_commitment_tx.htlcs().iter().zip(&holder_commitment_tx.counterparty_htlc_sigs).zip(htlc_sigs.iter().enumerate());
+                               let mut htlc_counterparty_sig_iter = holder_commitment_tx.counterparty_htlc_sigs.iter();
 
                                $({
                                        log_trace!(logger, "verifying htlc {}", $htlc_idx);
-                                       let remote_signature = Signature::from_der(&hex::decode($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
+                                       let remote_signature = Signature::from_der(&<Vec<u8>>::from_hex($counterparty_htlc_sig_hex).unwrap()[..]).unwrap();
 
                                        let ref htlc = htlcs[$htlc_idx];
-                                       let htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.context.feerate_per_kw,
+                                       let mut htlc_tx = chan_utils::build_htlc_transaction(&unsigned_tx.txid, chan.context.feerate_per_kw,
                                                chan.context.get_counterparty_selected_contest_delay().unwrap(),
                                                &htlc, $opt_anchors, &keys.broadcaster_delayed_payment_key, &keys.revocation_key);
                                        let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, $opt_anchors, &keys);
                                        let htlc_sighashtype = if $opt_anchors.supports_anchors_zero_fee_htlc_tx() { EcdsaSighashType::SinglePlusAnyoneCanPay } else { EcdsaSighashType::All };
                                        let htlc_sighash = Message::from_slice(&sighash::SighashCache::new(&htlc_tx).segwit_signature_hash(0, &htlc_redeemscript, htlc.amount_msat / 1000, htlc_sighashtype).unwrap()[..]).unwrap();
-                                       assert!(secp_ctx.verify_ecdsa(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key).is_ok(), "verify counterparty htlc sig");
+                                       assert!(secp_ctx.verify_ecdsa(&htlc_sighash, &remote_signature, &keys.countersignatory_htlc_key.to_public_key()).is_ok(), "verify counterparty htlc sig");
 
                                        let mut preimage: Option<PaymentPreimage> = None;
                                        if !htlc.offered {
                                                for i in 0..5 {
-                                                       let out = PaymentHash(Sha256::hash(&[i; 32]).into_inner());
+                                                       let out = PaymentHash(Sha256::hash(&[i; 32]).to_byte_array());
                                                        if out == htlc.payment_hash {
                                                                preimage = Some(PaymentPreimage([i; 32]));
                                                        }
@@ -8324,20 +9220,32 @@ mod tests {
                                                assert!(preimage.is_some());
                                        }
 
-                                       let htlc_sig = htlc_sig_iter.next().unwrap();
+                                       let htlc_counterparty_sig = htlc_counterparty_sig_iter.next().unwrap();
+                                       let htlc_holder_sig = signer.sign_holder_htlc_transaction(&htlc_tx, 0, &HTLCDescriptor {
+                                               channel_derivation_parameters: ChannelDerivationParameters {
+                                                       value_satoshis: chan.context.channel_value_satoshis,
+                                                       keys_id: chan.context.channel_keys_id,
+                                                       transaction_parameters: chan.context.channel_transaction_parameters.clone(),
+                                               },
+                                               commitment_txid: trusted_tx.txid(),
+                                               per_commitment_number: trusted_tx.commitment_number(),
+                                               per_commitment_point: trusted_tx.per_commitment_point(),
+                                               feerate_per_kw: trusted_tx.feerate_per_kw(),
+                                               htlc: htlc.clone(),
+                                               preimage: preimage.clone(),
+                                               counterparty_sig: *htlc_counterparty_sig,
+                                       }, &secp_ctx).unwrap();
                                        let num_anchors = if $opt_anchors.supports_anchors_zero_fee_htlc_tx() { 2 } else { 0 };
-                                       assert_eq!((htlc_sig.0).0.transaction_output_index, Some($htlc_idx + num_anchors), "output index");
+                                       assert_eq!(htlc.transaction_output_index, Some($htlc_idx + num_anchors), "output index");
 
-                                       let signature = Signature::from_der(&hex::decode($htlc_sig_hex).unwrap()[..]).unwrap();
-                                       assert_eq!(signature, *(htlc_sig.1).1, "htlc sig");
-                                       let index = (htlc_sig.1).0;
-                                       let channel_parameters = chan.context.channel_transaction_parameters.as_holder_broadcastable();
+                                       let signature = Signature::from_der(&<Vec<u8>>::from_hex($htlc_sig_hex).unwrap()[..]).unwrap();
+                                       assert_eq!(signature, htlc_holder_sig, "htlc sig");
                                        let trusted_tx = holder_commitment_tx.trust();
-                                       log_trace!(logger, "htlc_tx = {}", hex::encode(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))));
-                                       assert_eq!(serialize(&trusted_tx.get_signed_htlc_tx(&channel_parameters, index, &(htlc_sig.0).1, (htlc_sig.1).1, &preimage))[..],
-                                                       hex::decode($htlc_tx_hex).unwrap()[..], "htlc tx");
+                                       htlc_tx.input[0].witness = trusted_tx.build_htlc_input_witness($htlc_idx, htlc_counterparty_sig, &htlc_holder_sig, &preimage);
+                                       log_trace!(logger, "htlc_tx = {}", serialize(&htlc_tx).as_hex());
+                                       assert_eq!(serialize(&htlc_tx)[..], <Vec<u8>>::from_hex($htlc_tx_hex).unwrap()[..], "htlc tx");
                                })*
-                               assert!(htlc_sig_iter.next().is_none());
+                               assert!(htlc_counterparty_sig_iter.next().is_none());
                        } }
                }
 
@@ -8366,7 +9274,7 @@ mod tests {
                                payment_hash: PaymentHash([0; 32]),
                                state: InboundHTLCState::Committed,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0000000000000000000000000000000000000000000000000000000000000000").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_inbound_htlcs.push({
@@ -8377,7 +9285,7 @@ mod tests {
                                payment_hash: PaymentHash([0; 32]),
                                state: InboundHTLCState::Committed,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_outbound_htlcs.push({
@@ -8389,8 +9297,9 @@ mod tests {
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
+                               blinding_point: None,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_outbound_htlcs.push({
@@ -8402,8 +9311,9 @@ mod tests {
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
+                               blinding_point: None,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_inbound_htlcs.push({
@@ -8414,7 +9324,7 @@ mod tests {
                                payment_hash: PaymentHash([0; 32]),
                                state: InboundHTLCState::Committed,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0404040404040404040404040404040404040404040404040404040404040404").unwrap()).to_byte_array();
                        out
                });
 
@@ -8800,7 +9710,7 @@ mod tests {
                                payment_hash: PaymentHash([0; 32]),
                                state: InboundHTLCState::Committed,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_outbound_htlcs.clear();
@@ -8813,8 +9723,9 @@ mod tests {
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
+                               blinding_point: None,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).to_byte_array();
                        out
                });
                chan.context.pending_outbound_htlcs.push({
@@ -8826,8 +9737,9 @@ mod tests {
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
+                               blinding_point: None,
                        };
-                       out.payment_hash.0 = Sha256::hash(&hex::decode("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).into_inner();
+                       out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).to_byte_array();
                        out
                });
 
@@ -8874,23 +9786,23 @@ mod tests {
                // Test vectors from BOLT 3 Appendix D:
 
                let mut seed = [0; 32];
-               seed[0..32].clone_from_slice(&hex::decode("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
+               seed[0..32].clone_from_slice(&<Vec<u8>>::from_hex("0000000000000000000000000000000000000000000000000000000000000000").unwrap());
                assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
-                          hex::decode("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
+                          <Vec<u8>>::from_hex("02a40c85b6f28da08dfdbe0926c53fab2de6d28c10301f8f7c4073d5e42e3148").unwrap()[..]);
 
-               seed[0..32].clone_from_slice(&hex::decode("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
+               seed[0..32].clone_from_slice(&<Vec<u8>>::from_hex("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF").unwrap());
                assert_eq!(chan_utils::build_commitment_secret(&seed, 281474976710655),
-                          hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
+                          <Vec<u8>>::from_hex("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap()[..]);
 
                assert_eq!(chan_utils::build_commitment_secret(&seed, 0xaaaaaaaaaaa),
-                          hex::decode("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
+                          <Vec<u8>>::from_hex("56f4008fb007ca9acf0e15b054d5c9fd12ee06cea347914ddbaed70d1c13a528").unwrap()[..]);
 
                assert_eq!(chan_utils::build_commitment_secret(&seed, 0x555555555555),
-                          hex::decode("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
+                          <Vec<u8>>::from_hex("9015daaeb06dba4ccc05b91b2f73bd54405f2be9f217fbacd3c5ac2e62327d31").unwrap()[..]);
 
-               seed[0..32].clone_from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
+               seed[0..32].clone_from_slice(&<Vec<u8>>::from_hex("0101010101010101010101010101010101010101010101010101010101010101").unwrap());
                assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
-                          hex::decode("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
+                          <Vec<u8>>::from_hex("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
        }
 
        #[test]
@@ -8898,26 +9810,23 @@ mod tests {
                // Test vectors from BOLT 3 Appendix E:
                let secp_ctx = Secp256k1::new();
 
-               let base_secret = SecretKey::from_slice(&hex::decode("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
-               let per_commitment_secret = SecretKey::from_slice(&hex::decode("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
+               let base_secret = SecretKey::from_slice(&<Vec<u8>>::from_hex("000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f").unwrap()[..]).unwrap();
+               let per_commitment_secret = SecretKey::from_slice(&<Vec<u8>>::from_hex("1f1e1d1c1b1a191817161514131211100f0e0d0c0b0a09080706050403020100").unwrap()[..]).unwrap();
 
                let base_point = PublicKey::from_secret_key(&secp_ctx, &base_secret);
-               assert_eq!(base_point.serialize()[..], hex::decode("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
+               assert_eq!(base_point.serialize()[..], <Vec<u8>>::from_hex("036d6caac248af96f6afa7f904f550253a0f3ef3f5aa2fe6838a95b216691468e2").unwrap()[..]);
 
                let per_commitment_point = PublicKey::from_secret_key(&secp_ctx, &per_commitment_secret);
-               assert_eq!(per_commitment_point.serialize()[..], hex::decode("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
-
-               assert_eq!(chan_utils::derive_public_key(&secp_ctx, &per_commitment_point, &base_point).serialize()[..],
-                               hex::decode("0235f2dbfaa89b57ec7b055afe29849ef7ddfeb1cefdb9ebdc43f5494984db29e5").unwrap()[..]);
+               assert_eq!(per_commitment_point.serialize()[..], <Vec<u8>>::from_hex("025f7117a78150fe2ef97db7cfc83bd57b2e2c0d0dd25eaf467a4a1c2a45ce1486").unwrap()[..]);
 
                assert_eq!(chan_utils::derive_private_key(&secp_ctx, &per_commitment_point, &base_secret),
-                               SecretKey::from_slice(&hex::decode("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
+                               SecretKey::from_slice(&<Vec<u8>>::from_hex("cbced912d3b21bf196a766651e436aff192362621ce317704ea2f75d87e7be0f").unwrap()[..]).unwrap());
 
-               assert_eq!(chan_utils::derive_public_revocation_key(&secp_ctx, &per_commitment_point, &base_point).serialize()[..],
-                               hex::decode("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
+               assert_eq!(RevocationKey::from_basepoint(&secp_ctx, &RevocationBasepoint::from(base_point), &per_commitment_point).to_public_key().serialize()[..],
+                               <Vec<u8>>::from_hex("02916e326636d19c33f13e8c0c3a03dd157f332f3e99c317c141dd865eb01f8ff0").unwrap()[..]);
 
                assert_eq!(chan_utils::derive_private_revocation_key(&secp_ctx, &per_commitment_secret, &base_secret),
-                               SecretKey::from_slice(&hex::decode("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
+                               SecretKey::from_slice(&<Vec<u8>>::from_hex("d09ffff62ddb2297ab000cc85bcb4283fdeb6aa052affbc9dddcf33b61078110").unwrap()[..]).unwrap());
        }
 
        #[test]
@@ -8932,12 +9841,12 @@ 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::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider,
-                       node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42).unwrap();
+                       node_b_node_id, &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42, None).unwrap();
 
                let mut channel_type_features = ChannelTypeFeatures::only_static_remote_key();
                channel_type_features.set_zero_conf_required();
 
-               let mut open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
+               let mut open_channel_msg = node_a_chan.get_open_channel(ChainHash::using_genesis_block(network));
                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::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider,
@@ -8967,7 +9876,7 @@ mod tests {
                let channel_a = OutboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
                        &channelmanager::provided_init_features(&UserConfig::default()), 10000000, 100000, 42,
-                       &config, 0, 42
+                       &config, 0, 42, None
                ).unwrap();
                assert!(!channel_a.context.channel_type.supports_anchors_zero_fee_htlc_tx());
 
@@ -8977,10 +9886,11 @@ mod tests {
 
                let channel_a = OutboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
-                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
+                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42,
+                       None
                ).unwrap();
 
-               let open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
+               let open_channel_msg = channel_a.get_open_channel(ChainHash::using_genesis_block(network));
                let channel_b = InboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
                        &channelmanager::provided_channel_type_features(&config), &channelmanager::provided_init_features(&config),
@@ -9014,11 +9924,12 @@ mod tests {
 
                let channel_a = OutboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
-                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
+                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42,
+                       None
                ).unwrap();
 
                // Set `channel_type` to `None` to force the implicit feature negotiation.
-               let mut open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
+               let mut open_channel_msg = channel_a.get_open_channel(ChainHash::using_genesis_block(network));
                open_channel_msg.channel_type = None;
 
                // Since A supports both `static_remote_key` and `option_anchors`, but B only accepts
@@ -9060,10 +9971,11 @@ mod tests {
                // B as it's not supported by LDK.
                let channel_a = OutboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b,
-                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42
+                       &channelmanager::provided_init_features(&config), 10000000, 100000, 42, &config, 0, 42,
+                       None
                ).unwrap();
 
-               let mut open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
+               let mut open_channel_msg = channel_a.get_open_channel(ChainHash::using_genesis_block(network));
                open_channel_msg.channel_type = Some(simple_anchors_channel_type.clone());
 
                let res = InboundV1Channel::<&TestKeysInterface>::new(
@@ -9079,10 +9991,10 @@ mod tests {
                // LDK.
                let mut channel_a = OutboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_b, &simple_anchors_init,
-                       10000000, 100000, 42, &config, 0, 42
+                       10000000, 100000, 42, &config, 0, 42, None
                ).unwrap();
 
-               let open_channel_msg = channel_a.get_open_channel(genesis_block(network).header.block_hash());
+               let open_channel_msg = channel_a.get_open_channel(ChainHash::using_genesis_block(network));
 
                let channel_b = InboundV1Channel::<&TestKeysInterface>::new(
                        &fee_estimator, &&keys_provider, &&keys_provider, node_id_a,
@@ -9107,7 +10019,7 @@ mod tests {
                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 chain_hash = ChainHash::using_genesis_block(network);
                let keys_provider = test_utils::TestKeysInterface::new(&seed, network);
 
                let mut config = UserConfig::default();
@@ -9129,9 +10041,10 @@ mod tests {
                        &config,
                        0,
                        42,
+                       None
                ).unwrap();
 
-               let open_channel_msg = node_a_chan.get_open_channel(genesis_block(network).header.block_hash());
+               let open_channel_msg = node_a_chan.get_open_channel(ChainHash::using_genesis_block(network));
                let node_b_node_id = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[7; 32]).unwrap());
                let mut node_b_chan = InboundV1Channel::<&TestKeysInterface>::new(
                        &feeest,
@@ -9159,7 +10072,7 @@ mod tests {
                let output_script = node_a_chan.context.get_funding_redeemscript();
                let tx = Transaction {
                        version: 1,
-                       lock_time: PackedLockTime::ZERO,
+                       lock_time: LockTime::ZERO,
                        input: Vec::new(),
                        output: vec![
                                TxOut {
@@ -9170,14 +10083,11 @@ mod tests {
                                },
                        ]};
                let funding_outpoint = OutPoint{ txid: tx.txid(), index: 0 };
-               let (mut node_a_chan, funding_created_msg) = node_a_chan.get_funding_created(
-                       tx.clone(),
-                       funding_outpoint,
-                       true,
-                       &&logger,
+               let funding_created_msg = node_a_chan.get_funding_created(
+                       tx.clone(), funding_outpoint, true, &&logger,
                ).map_err(|_| ()).unwrap();
                let (mut node_b_chan, funding_signed_msg, _) = node_b_chan.funding_created(
-                       &funding_created_msg,
+                       &funding_created_msg.unwrap(),
                        best_block,
                        &&keys_provider,
                        &&logger,
@@ -9192,12 +10102,10 @@ mod tests {
 
                // Receive funding_signed, but the channel will be configured to hold sending channel_ready and
                // broadcasting the funding transaction until the batch is ready.
-               let _ = node_a_chan.funding_signed(
-                       &funding_signed_msg,
-                       best_block,
-                       &&keys_provider,
-                       &&logger,
-               ).unwrap();
+               let res = node_a_chan.funding_signed(
+                       &funding_signed_msg.unwrap(), best_block, &&keys_provider, &&logger,
+               );
+               let (mut node_a_chan, _) = if let Ok(res) = res { res } else { panic!(); };
                let node_a_updates = node_a_chan.monitor_updating_restored(
                        &&logger,
                        &&keys_provider,
@@ -9209,11 +10117,7 @@ mod tests {
                // as the funding transaction depends on all channels in the batch becoming ready.
                assert!(node_a_updates.channel_ready.is_none());
                assert!(node_a_updates.funding_broadcastable.is_none());
-               assert_eq!(
-                       node_a_chan.context.channel_state,
-                       ChannelState::FundingSent as u32 |
-                       ChannelState::WaitingForBatch as u32,
-               );
+               assert_eq!(node_a_chan.context.channel_state, ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::WAITING_FOR_BATCH));
 
                // It is possible to receive a 0conf channel_ready from the remote node.
                node_a_chan.channel_ready(
@@ -9226,18 +10130,12 @@ mod tests {
                ).unwrap();
                assert_eq!(
                        node_a_chan.context.channel_state,
-                       ChannelState::FundingSent as u32 |
-                       ChannelState::WaitingForBatch as u32 |
-                       ChannelState::TheirChannelReady as u32,
+                       ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::WAITING_FOR_BATCH | AwaitingChannelReadyFlags::THEIR_CHANNEL_READY)
                );
 
                // Clear the ChannelState::WaitingForBatch only when called by ChannelManager.
                node_a_chan.set_batch_ready();
-               assert_eq!(
-                       node_a_chan.context.channel_state,
-                       ChannelState::FundingSent as u32 |
-                       ChannelState::TheirChannelReady as u32,
-               );
+               assert_eq!(node_a_chan.context.channel_state, ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::THEIR_CHANNEL_READY));
                assert!(node_a_chan.check_get_channel_ready(0).is_some());
        }
 }