Merge pull request #2748 from TheBlueMatt/2023-11-2675-followups
authorMatt Corallo <649246+TheBlueMatt@users.noreply.github.com>
Tue, 9 Jan 2024 23:22:48 +0000 (23:22 +0000)
committerGitHub <noreply@github.com>
Tue, 9 Jan 2024 23:22:48 +0000 (23:22 +0000)
Doc and style followups from #2675

1  2 
lightning/src/ln/channel.rs

index 1dfc6dc552fea205a01b27ee573c2de4315e803e,469eddd642f68686765896826a2621bf03c154f6..cd98418c5204d369759637fc88667b6d4255dca5
@@@ -37,12 -37,11 +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};
 -use crate::util::logger::Logger;
 +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;
@@@ -166,7 -165,6 +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
  }
  
  #[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>),
@@@ -225,7 -222,6 +225,7 @@@ impl<'a> Into<Option<&'a HTLCFailReason
        }
  }
  
 +#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
  struct OutboundHTLCOutput {
        htlc_id: u64,
        amount_msat: u64,
        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
                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,
                htlc_id: u64,
                err_packet: msgs::OnionErrorPacket,
        },
 +      FailMalformedHTLC {
 +              htlc_id: u64,
 +              failure_code: u16,
 +              sha256_of_onion: [u8; 32],
 +      },
 +}
 +
 +macro_rules! define_state_flags {
 +      ($flag_type_doc: expr, $flag_type: ident, [$(($flag_doc: expr, $flag: ident, $value: expr)),+], $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 }
 +              }
 +
 +              impl core::ops::Not for $flag_type {
 +                      type Output = Self;
 +                      fn not(self) -> Self::Output { Self(!self.0) }
 +              }
 +              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_doc: expr, FUNDED_STATE, $flag_type: ident, $flags: tt) => {
 +              define_state_flags!($flag_type_doc, $flag_type, $flags, FundedStateFlags::ALL.0);
 +              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;
  }
  
 -/// 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.
 +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),
 +              ("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),
 +              ("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),
 +              ("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)
 +      ]
 +);
 +
 +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),
 +              ("Indicates we have received their `open_channel`/`accept_channel` message.",
 +                      THEIR_INIT_SENT, state_flags::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),
 +              ("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),
 +              ("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)
 +      ]
 +);
 +
 +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)
 +      ]
 +);
 +
 +#[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, $state_flag: expr, [$($state: ident),+]) => {
 +              #[allow(unused)]
 +              fn $get(&self) -> bool {
 +                      match self {
 +                              $(
 +                                      ChannelState::$state(flags) => flags.is_set($state_flag.into()),
 +                              )*
 +                              _ => false,
 +                      }
 +              }
 +              #[allow(unused)]
 +              fn $set(&mut self) {
 +                      match self {
 +                              $(
 +                                      ChannelState::$state(flags) => *flags |= $state_flag,
 +                              )*
 +                              _ => debug_assert!(false, "Attempted to set flag on unexpected ChannelState"),
 +                      }
 +              }
 +              #[allow(unused)]
 +              fn $clear(&mut self) {
 +                      match self {
 +                              $(
 +                                      ChannelState::$state(flags) => *flags &= !($state_flag),
 +                              )*
 +                              _ => debug_assert!(false, "Attempted to clear flag on unexpected ChannelState"),
 +                      }
 +              }
 +      };
 +      ($get: ident, $set: ident, $clear: ident, $state_flag: expr, FUNDED_STATES) => {
 +              impl_state_flag!($get, $set, $clear, $state_flag, [AwaitingChannelReady, ChannelReady]);
 +      };
 +      ($get: ident, $set: ident, $clear: ident, $state_flag: expr, $state: ident) => {
 +              impl_state_flag!($get, $set, $clear, $state_flag, [$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 should_force_holding_cell(&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, "The holding cell is only valid within ChannelReady");
 +                              false
 +                      },
 +              }
 +      }
 +
 +      impl_state_flag!(is_peer_disconnected, set_peer_disconnected, clear_peer_disconnected,
 +              FundedStateFlags::PEER_DISCONNECTED, FUNDED_STATES);
 +      impl_state_flag!(is_monitor_update_in_progress, set_monitor_update_in_progress, clear_monitor_update_in_progress,
 +              FundedStateFlags::MONITOR_UPDATE_IN_PROGRESS, FUNDED_STATES);
 +      impl_state_flag!(is_local_shutdown_sent, set_local_shutdown_sent, clear_local_shutdown_sent,
 +              FundedStateFlags::LOCAL_SHUTDOWN_SENT, FUNDED_STATES);
 +      impl_state_flag!(is_remote_shutdown_sent, set_remote_shutdown_sent, clear_remote_shutdown_sent,
 +              FundedStateFlags::REMOTE_SHUTDOWN_SENT, FUNDED_STATES);
 +      impl_state_flag!(is_our_channel_ready, set_our_channel_ready, clear_our_channel_ready,
 +              AwaitingChannelReadyFlags::OUR_CHANNEL_READY, AwaitingChannelReady);
 +      impl_state_flag!(is_their_channel_ready, set_their_channel_ready, clear_their_channel_ready,
 +              AwaitingChannelReadyFlags::THEIR_CHANNEL_READY, AwaitingChannelReady);
 +      impl_state_flag!(is_waiting_for_batch, set_waiting_for_batch, clear_waiting_for_batch,
 +              AwaitingChannelReadyFlags::WAITING_FOR_BATCH, AwaitingChannelReady);
 +      impl_state_flag!(is_awaiting_remote_revoke, set_awaiting_remote_revoke, clear_awaiting_remote_revoke,
 +              ChannelReadyFlags::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;
  
@@@ -636,33 -407,6 +636,33 @@@ 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 {
@@@ -732,10 -476,9 +732,10 @@@ 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.
@@@ -798,6 -541,7 +798,6 @@@ pub(super) struct MonitorRestoreUpdate
  pub(super) struct SignerResumeUpdates {
        pub commitment_update: Option<msgs::CommitmentUpdate>,
        pub funding_signed: Option<msgs::FundingSigned>,
 -      pub funding_created: Option<msgs::FundingCreated>,
        pub channel_ready: Option<msgs::ChannelReady>,
  }
  
@@@ -821,8 -565,6 +821,8 @@@ pub(crate) struct ShutdownResult 
        /// 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) counterparty_node_id: PublicKey,
  }
  
  /// If the majority of the channels funds are to the fundee and the initiator holds only just
@@@ -905,7 -647,7 +905,7 @@@ pub(super) enum ChannelPhase<SP: Deref
  
  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 {
@@@ -964,7 -706,7 +964,7 @@@ pub(super) struct ChannelContext<SP: De
        /// 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
  
        latest_monitor_update_id: u64,
  
 -      holder_signer: ChannelSignerType<<SP::Target as SignerProvider>::Signer>,
 +      holder_signer: ChannelSignerType<SP>,
        shutdown_scriptpubkey: Option<ShutdownScript>,
        destination_script: ScriptBuf,
  
@@@ -1261,55 -1003,49 +1261,55 @@@ impl<SP: Deref> ChannelContext<SP> wher
  
        /// 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:
  
        /// Returns the holder signer for this channel.
        #[cfg(test)]
 -      pub fn get_signer(&self) -> &ChannelSignerType<<SP::Target as SignerProvider>::Signer> {
 +      pub fn get_signer(&self) -> &ChannelSignerType<SP> {
                return &self.holder_signer
        }
  
        /// 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
                        }
                }
  
 +              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"),
                                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;
                                                        }
                                                }
                        }
                }
  
 -              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 {
                        };
  
                        if let Some(preimage) = preimage_opt {
 -                              preimages.push(preimage);
 +                              outbound_htlc_preimages.push(preimage);
                        }
  
                        if include {
                        }
                }
  
 -              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)]
                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,
                        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,
                }
        }
  
        /// 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();
                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.
  
        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
 +              match self.channel_state {
 +                      ChannelState::FundingNegotiated => f(),
 +                      ChannelState::AwaitingChannelReady(flags) => if flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH) {
 +                              f()
 +                      } else {
 +                              None
 +                      },
 +                      _ => None,
                }
        }
  
                // 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.
                        }
                }
                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 {
 +                      let generate_monitor_update = match self.channel_state {
 +                              ChannelState::AwaitingChannelReady(_)|ChannelState::ChannelReady(_)|ChannelState::ShutdownComplete => true,
 +                              _ => false,
 +                      };
 +                      if generate_monitor_update {
                                self.latest_monitor_update_id = CLOSED_CHANNEL_UPDATE_ID;
                                Some((self.get_counterparty_node_id(), funding_txo, ChannelMonitorUpdate {
                                        update_id: self.latest_monitor_update_id,
 +                                      counterparty_node_id: Some(self.counterparty_node_id),
                                        updates: vec![ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast }],
                                }))
                        } else { None }
                } else { None };
                let unbroadcasted_batch_funding_txid = self.unbroadcasted_batch_funding_txid();
  
 -              self.channel_state = ChannelState::ShutdownComplete as u32;
 +              self.channel_state = ChannelState::ShutdownComplete;
                self.update_time_counter += 1;
                ShutdownResult {
                        monitor_update,
                        dropped_outbound_htlcs,
                        unbroadcasted_batch_funding_txid,
 +                      channel_id: self.channel_id,
 +                      counterparty_node_id: self.counterparty_node_id,
                }
        }
  
 -      /// Only allowed after [`Self::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.build_remote_transaction_keys();
 -              let counterparty_initial_commitment_tx = self.build_commitment_transaction(self.cur_counterparty_commitment_transaction_number, &counterparty_keys, false, false, logger).tx;
 -              let signature = match &self.holder_signer {
 -                      // TODO (taproot|arik): move match into calling method for Taproot
 -                      ChannelSignerType::Ecdsa(ecdsa) => {
 -                              ecdsa.sign_counterparty_commitment(&counterparty_initial_commitment_tx, Vec::new(), &self.secp_ctx)
 -                                      .map(|(sig, _)| sig).ok()?
 -                      }
 -              };
 -
 -              if self.signer_pending_funding {
 -                      log_trace!(logger, "Counterparty commitment signature ready for funding_created message: clearing signer_pending_funding");
 -                      self.signer_pending_funding = false;
 -              }
 -
 -              Some(msgs::FundingCreated {
 -                      temporary_channel_id: self.temporary_channel_id.unwrap(),
 -                      funding_txid: self.channel_transaction_parameters.funding_outpoint.as_ref().unwrap().txid,
 -                      funding_output_index: self.channel_transaction_parameters.funding_outpoint.as_ref().unwrap().index,
 -                      signature,
 -                      #[cfg(taproot)]
 -                      partial_signature_with_nonce: None,
 -                      #[cfg(taproot)]
 -                      next_local_nonce: None,
 -              })
 -      }
 -
        /// 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();
                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(), &self.secp_ctx)
 +                              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,
                                        .ok();
  
                                if funding_signed.is_none() {
 -                                      log_trace!(logger, "Counterparty commitment signature not available for funding_signed message; setting signer_pending_funding");
 -                                      self.signer_pending_funding = true;
 +                                      #[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!()
                }
        }
  }
@@@ -2526,67 -2269,9 +2524,67 @@@ 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 (u16, [u8; 32]) {
 +      type Message = msgs::UpdateFailMalformedHTLC; // (failure_code, sha256_of_onion)
 +      fn to_message(self, htlc_id: u64, channel_id: ChannelId) -> Self::Message {
 +              msgs::UpdateFailMalformedHTLC {
 +                      htlc_id,
 +                      channel_id,
 +                      failure_code: self.0,
 +                      sha256_of_onion: self.1
 +              }
 +      }
 +      fn to_inbound_htlc_state(self) -> InboundHTLCState {
 +              InboundHTLCState::LocalRemoved(
 +                      InboundHTLCRemovalReason::FailMalformed((self.1, self.0))
 +              )
 +      }
 +      fn to_htlc_update_awaiting_ack(self, htlc_id: u64) -> HTLCUpdateAwaitingACK {
 +              HTLCUpdateAwaitingACK::FailMalformedHTLC {
 +                      htlc_id,
 +                      failure_code: self.0,
 +                      sha256_of_onion: 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>,
        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.should_force_holding_cell());
                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;
                // 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
                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(),
                        }],
                };
  
 -              if (self.context.channel_state & (ChannelState::AwaitingRemoteRevoke as u32 | ChannelState::PeerDisconnected as u32 | ChannelState::MonitorUpdateInProgress as u32)) != 0 {
 +              if self.context.channel_state.should_force_holding_cell() {
                        // 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
                                                        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
                                        _ => {}
                                }
                        }
 -                      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,
                        });
                        .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, (failure_code, sha256_of_onion), 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
        /// 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_packet: 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
                        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.should_force_holding_cell() {
                        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;
                }
                                                        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()));
                                }
                        }
                        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_packet.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_packet.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_packet.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
                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()));
                }
                        }
                }
  
 -              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 & !FundedStateFlags::ALL;
 +                              debug_assert!(!flags.is_set(AwaitingChannelReadyFlags::OUR_CHANNEL_READY) || !flags.is_set(AwaitingChannelReadyFlags::WAITING_FOR_BATCH));
 +                              if flags & !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 & !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 =
                                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;
        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 {
                        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");
                        }
        }
  
        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) {
 +              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()));
                }
  
        }
  
        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()));
                }
  
        }
  
        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()));
                }
  
        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()));
                }
  
                        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...
                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,
                // 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_for_send includes the right HTLCs.
                        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().
        ) -> (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.should_force_holding_cell() {
                        self.free_holding_cell_htlcs(fee_estimator, logger)
                } else { (None, Vec::new()) }
        }
        ) -> (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(),
                        };
  
                                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 {
                                                        }
                                                }
                                        },
 +                                      &HTLCUpdateAwaitingACK::FailMalformedHTLC { htlc_id, failure_code, sha256_of_onion } => {
 +                                              match self.fail_htlc(htlc_id, (failure_code, sha256_of_onion), false, logger) {
 +                                                      Ok(update_fail_malformed_opt) => {
 +                                                              debug_assert!(update_fail_malformed_opt.is_some()); // See above comment
 +                                                              update_fail_count += 1;
 +                                                      },
 +                                                      Err(e) => {
 +                                                              if let ChannelError::Ignore(_) = e {}
 +                                                              else {
 +                                                                      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() {
        ) -> 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()));
                }
  
                        }
                }
  
 -              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
                                        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)
                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,
                // (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);
                        }
                }
  
 -              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 {
                        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;
                }
  
        /// 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(());
  
                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(())
        }
                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
                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;
                }
  
                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 {
                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)?;
  
        /// Indicates that the signer may have some signatures for us, so we should retry if we're
        /// blocked.
 -      #[allow(unused)]
 +      #[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()
                let channel_ready = if funding_signed.is_some() {
                        self.check_get_channel_ready(0)
                } else { None };
 -              let funding_created = if self.context.signer_pending_funding && self.context.is_outbound() {
 -                      self.context.get_funding_created_msg(logger)
 -              } else { None };
  
 -              log_trace!(logger, "Signer unblocked with {} commitment_update, {} funding_signed, {} funding_created, and {} channel_ready",
 +              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 funding_created.is_some() { "a" } else { "no" },
                        if channel_ready.is_some() { "a" } else { "no" });
  
                SignerResumeUpdates {
                        commitment_update,
                        funding_signed,
 -                      funding_created,
                        channel_ready,
                }
        }
                                        cltv_expiry: htlc.cltv_expiry,
                                        onion_routing_packet: (**onion_packet).clone(),
                                        skimmed_fee_msat: htlc.skimmed_fee_msat,
 +                                      blinding_point: htlc.blinding_point,
                                });
                        }
                }
                        }
                        update
                } else {
 -                      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;
 +                      #[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(());
                        }
 -                      return Err(());
                };
                Ok(msgs::CommitmentUpdate {
                        update_add_htlcs, update_fulfill_htlcs, update_fail_htlcs, update_fail_malformed_htlcs, update_fee,
  
        /// 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,
                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.
                        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)
                        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));
  
                // 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, 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()));
                                }
                        });
                }
  
 -              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();
                }
                                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,
                                        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,
 +                      )))
                }
        }
  
                                                max_fee_satoshis: our_max_fee,
                                        }),
                                }), None, None))
 -                      }
 +                      },
 +                      // TODO (taproot|arik)
 +                      #[cfg(taproot)]
 +                      _ => todo!()
                }
        }
  
                &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...
                                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_hex_string())));
                // 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,
  
                // 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(),
                                }],
                        }
                });
  
 -              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))
                -> 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() {
                        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, None));
                }
                                        monitor_update: None,
                                        dropped_outbound_htlcs: Vec::new(),
                                        unbroadcasted_batch_funding_txid: self.context.unbroadcasted_batch_funding_txid(),
 +                                      channel_id: self.context.channel_id,
 +                                      counterparty_node_id: self.context.counterparty_node_id,
                                };
                                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), Some(shutdown_result)));
                        }
                                                                monitor_update: None,
                                                                dropped_outbound_htlcs: Vec::new(),
                                                                unbroadcasted_batch_funding_txid: self.context.unbroadcasted_batch_funding_txid(),
 +                                                              channel_id: self.context.channel_id,
 +                                                              counterparty_node_id: self.context.counterparty_node_id,
                                                        };
 -                                                      self.context.channel_state = ChannelState::ShutdownComplete as u32;
 +                                                      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), Some(shutdown_result))
                                                                max_fee_satoshis: our_max_fee,
                                                        }),
                                                }), signed_tx, shutdown_result))
 -                                      }
 +                                      },
 +                                      // TODO (taproot|arik)
 +                                      #[cfg(taproot)]
 +                                      _ => todo!()
                                }
                        }
                }
        }
  
        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 {
        }
  
        #[cfg(test)]
 -      pub fn get_signer(&self) -> &ChannelSignerType<<SP::Target as SignerProvider>::Signer> {
 +      pub fn get_signer(&self) -> &ChannelSignerType<SP> {
                &self.context.holder_signer
        }
  
        /// 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.
        /// 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 & !(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.
  
        /// 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 {
  
                // 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 & !FundedStateFlags::ALL).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 & !FundedStateFlags::ALL == 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 & !FundedStateFlags::ALL == 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 {
                        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
                                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);
                }
  
                        // 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::<(ChainHash, &&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?");
                        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;
                }
                                        node_signature: our_node_sig,
                                        bitcoin_signature: our_bitcoin_sig,
                                })
 -                      }
 +                      },
 +                      // TODO (taproot|arik)
 +                      #[cfg(taproot)]
 +                      _ => todo!()
                }
        }
  
                                                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()))
        /// 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
                        // (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,
        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 */ }
        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;
                                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
                        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.should_force_holding_cell();
                log_debug!(logger, "Pushing new outbound HTLC with hash {} for {} msat {}",
                        payment_hash, amount_msat,
                        if force_holding_cell { "into holding cell" }
                                source,
                                onion_routing_packet,
                                skimmed_fee_msat,
 +                              blinding_point,
                        });
                        return Ok(None);
                }
                        cltv_expiry,
                        state: OutboundHTLCState::LocalAnnounced(Box::new(onion_routing_packet.clone())),
                        source,
 +                      blinding_point,
                        skimmed_fee_msat,
                });
  
                        cltv_expiry,
                        onion_routing_packet,
                        skimmed_fee_msat,
 +                      blinding_point,
                };
                self.context.next_holder_htlc_id += 1;
  
                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(),
                                to_countersignatory_value_sat: Some(counterparty_commitment_tx.to_countersignatory_value_sat()),
                        }]
                };
 -              self.context.channel_state |= ChannelState::AwaitingRemoteRevoke as u32;
 +              self.context.channel_state.set_awaiting_remote_revoke();
                monitor_update
        }
  
                                                htlcs.push(htlc);
                                        }
  
 -                                      let res = ecdsa.sign_counterparty_commitment(&commitment_stats.tx, commitment_stats.preimages, &self.context.secp_ctx)
 -                                              .map_err(|_| ChannelError::Ignore("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;
  
                                        #[cfg(taproot)]
                                        partial_signature_with_nonce: None,
                                }, (counterparty_commitment_txid, commitment_stats.htlcs_included)))
 -                      }
 +                      },
 +                      // TODO (taproot|arik)
 +                      #[cfg(taproot)]
 +                      _ => todo!()
                }
        }
  
        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(_) => {
  
        /// 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)>, Option<ShutdownResult>), APIError>
 +      -> Result<(msgs::Shutdown, Option<ChannelMonitorUpdate>, Vec<(HTLCSource, PaymentHash)>), APIError>
        {
                for htlc in self.context.pending_outbound_htlcs.iter() {
                        if let OutboundHTLCState::LocalAnnounced(_) = htlc.state {
                                return Err(APIError::APIMisuseError{err: "Cannot begin shutdown with pending HTLCs. Process pending events first".to_owned()});
                        }
                }
 -              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,
                                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;
 -              let shutdown_result = if self.context.channel_state & !STATE_FLAGS < ChannelState::FundingSent as u32 {
 -                      let shutdown_result = ShutdownResult {
 -                              monitor_update: None,
 -                              dropped_outbound_htlcs: Vec::new(),
 -                              unbroadcasted_batch_funding_txid: self.context.unbroadcasted_batch_funding_txid(),
 -                      };
 -                      self.context.channel_state = ChannelState::ShutdownComplete as u32;
 -                      Some(shutdown_result)
 -              } else {
 -                      self.context.channel_state |= ChannelState::LocalShutdownSent as u32;
 -                      None
 -              };
 +              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(),
                                }],
                debug_assert!(!self.is_shutdown() || monitor_update.is_none(),
                        "we can't both complete shutdown and return a monitor update");
  
 -              Ok((shutdown, monitor_update, dropped_outbound_htlcs, shutdown_result))
 +              Ok((shutdown, monitor_update, dropped_outbound_htlcs))
        }
  
        pub fn inflight_htlc_sources(&self) -> impl Iterator<Item=(&HTLCSource, &PaymentHash)> {
@@@ -6260,7 -5960,7 +6258,7 @@@ impl<SP: Deref> OutboundV1Channel<SP> w
                        }
                }
  
 -              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()}),
                };
  
                                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,
                })
        }
  
 +      /// 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;
 +              let signature = match &self.context.holder_signer {
 +                      // TODO (taproot|arik): move match into calling method for Taproot
 +                      ChannelSignerType::Ecdsa(ecdsa) => {
 +                              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
        /// a funding_created message for the remote peer.
        /// Panics if called at some time other than immediately after initial handshake, if called twice,
        /// 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>, Option<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) ||
  
                // Now that we're past error-generating stuff, update our local state:
  
 -              self.context.channel_state = ChannelState::FundingCreated as u32;
 +              self.context.channel_state = ChannelState::FundingNegotiated;
                self.context.channel_id = funding_txo.to_channel_id();
  
                // If the funding transaction is a coinbase transaction, we need to set the minimum depth to 100.
                self.context.funding_transaction = Some(funding_transaction);
                self.context.is_batch_funding = Some(()).filter(|_| is_batch_funding);
  
 -              let funding_created = self.context.get_funding_created_msg(logger);
 +              let funding_created = self.get_funding_created_msg(logger);
                if funding_created.is_none() {
 -                      if !self.context.signer_pending_funding {
 -                              log_trace!(logger, "funding_created awaiting signer; setting signer_pending_funding");
 -                              self.context.signer_pending_funding = true;
 +                      #[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;
 +                              }
                        }
                }
  
 -              let channel = Channel {
 -                      context: self.context,
 -              };
 -
 -              Ok((channel, funding_created))
 +              Ok(funding_created)
        }
  
        fn get_initial_channel_type(config: &UserConfig, their_features: &InitFeatures) -> ChannelTypeFeatures {
        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(());
                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");
                }
  
                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 {
                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);
 +              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.
@@@ -6845,41 -6394,6 +6843,41 @@@ pub(super) struct InboundV1Channel<SP: 
        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!
                          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);
                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 {
                        }
                }
  
 -              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())),
                };
  
                                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,
  
                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 {
  
        pub fn funding_created<L: Deref>(
                mut self, msg: &msgs::FundingCreated, best_block: BestBlock, signer_provider: &SP, logger: &L
 -      ) -> Result<(Channel<SP>, Option<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.
  
                // Now that we're past error-generating stuff, update our local state:
  
 -              self.context.channel_state = ChannelState::FundingSent as u32;
 +              self.context.channel_state = ChannelState::AwaitingChannelReady(AwaitingChannelReadyFlags::new());
                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;
                                                          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_commitment_tx.trust().txid(), Vec::new(),
                        self.context.cur_counterparty_commitment_transaction_number + 1,
@@@ -7460,13 -6991,7 +7458,13 @@@ impl<SP: Deref> Writeable for Channel<S
                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();
 +                      }
 +                      channel_state.to_u32().write(writer)?;
 +              }
                self.context.channel_value_satoshis.write(writer)?;
  
                self.context.latest_monitor_update_id.write(writer)?;
  
                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)?;
                                        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)?;
                                        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)?;
                                        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)?;
 +                              }
                        }
                }
  
                        (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(())
@@@ -7801,7 -7317,7 +7799,7 @@@ impl<'a, 'b, 'c, ES: Deref, SP: Deref> 
                }
  
                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)?;
                                        _ => return Err(DecodeError::InvalidValue),
                                },
                                skimmed_fee_msat: None,
 +                              blinding_point: None,
                        });
                }
  
                                        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)?,
  
                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),
                        (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)
                        // 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 {
@@@ -8332,15 -7805,13 +8330,15 @@@ mod tests 
        use bitcoin::blockdata::transaction::{Transaction, TxOut};
        use bitcoin::blockdata::opcodes;
        use bitcoin::network::constants::Network;
 -      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::channelmanager::{self, HTLCSource, PaymentId};
        use crate::ln::channel::InitFeatures;
 -      use crate::ln::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::{self, htlc_success_tx_weight, htlc_timeout_tx_weight};
        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};
        }
  
        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<ScriptBuf, ()> {
 +              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(&<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());
                        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_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.unwrap(), 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.
                                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
                        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_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.unwrap(), 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.
                        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_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.unwrap(), 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 {
                assert!(!node_a_chan.channel_update(&update).unwrap());
        }
  
 -      #[cfg(feature = "_test_vectors")]
 +      #[test]
 +      fn blinding_point_skimmed_fee_malformed_ser() {
 +              // Ensure that channel blinding points, skimmed fees, and malformed HTLCs are (de)serialized
 +              // properly.
 +              let feeest = LowerBoundedFeeEstimator::new(&TestFeeEstimator{fee_est: 15000});
 +              let secp_ctx = Secp256k1::new();
 +              let seed = [42; 32];
 +              let network = Network::Testnet;
 +              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 outbound_chan = OutboundV1Channel::<&TestKeysInterface>::new(&feeest, &&keys_provider, &&keys_provider, node_b_node_id, &features, 10000000, 100000, 42, &config, 0, 42, None).unwrap();
 +              let mut chan = Channel { context: outbound_chan.context };
 +
 +              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(all(feature = "_test_vectors", not(feature = "grind_signatures")))]
        #[test]
        fn outbound_commitment_test() {
                use bitcoin::sighash;
                use bitcoin::hashes::hex::FromHex;
                use bitcoin::hash_types::Txid;
                use bitcoin::secp256k1::Message;
 -              use crate::sign::{ChannelDerivationParameters, HTLCDescriptor, 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};
  
                // 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(
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
 +                              blinding_point: None,
                        };
                        out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0202020202020202020202020202020202020202020202020202020202020202").unwrap()).to_byte_array();
                        out
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
 +                              blinding_point: None,
                        };
                        out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0303030303030303030303030303030303030303030303030303030303030303").unwrap()).to_byte_array();
                        out
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
 +                              blinding_point: None,
                        };
                        out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).to_byte_array();
                        out
                                state: OutboundHTLCState::Committed,
                                source: HTLCSource::dummy(),
                                skimmed_fee_msat: None,
 +                              blinding_point: None,
                        };
                        out.payment_hash.0 = Sha256::hash(&<Vec<u8>>::from_hex("0505050505050505050505050505050505050505050505050505050505050505").unwrap()).to_byte_array();
                        out
                assert_eq!(chan_utils::build_commitment_secret(&seed, 1),
                           <Vec<u8>>::from_hex("915c75942a26bb3a433a8ce2cb0427c29ec6c1775cfc78328b57f6ba7bfeaa9c").unwrap()[..]);
        }
 -      
 +
        #[test]
        fn test_key_derivation() {
                // Test vectors from BOLT 3 Appendix E:
                                },
                        ]};
                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.unwrap(),
  
                // 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.unwrap(),
 -                      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,
                // 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(
                ).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());
        }
  }