+impl core::fmt::Display for ClosureReason {
+ fn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {
+ f.write_str("Channel closed because ")?;
+ match self {
+ ClosureReason::CounterpartyForceClosed { peer_msg } => {
+ f.write_str("counterparty force-closed with message ")?;
+ f.write_str(&peer_msg)
+ },
+ ClosureReason::HolderForceClosed => f.write_str("user manually force-closed the channel"),
+ ClosureReason::CooperativeClosure => f.write_str("the channel was cooperatively closed"),
+ ClosureReason::CommitmentTxConfirmed => f.write_str("commitment or closing transaction was confirmed on chain."),
+ ClosureReason::FundingTimedOut => write!(f, "funding transaction failed to confirm within {} blocks", FUNDING_CONF_DEADLINE_BLOCKS),
+ ClosureReason::ProcessingError { err } => {
+ f.write_str("of an exception: ")?;
+ f.write_str(&err)
+ },
+ ClosureReason::DisconnectedPeer => f.write_str("the peer disconnected prior to the channel being funded"),
+ ClosureReason::OutdatedChannelManager => f.write_str("the ChannelManager read from disk was stale compared to ChannelMonitor(s)"),
+ }
+ }
+}
+
+impl_writeable_tlv_based_enum_upgradable!(ClosureReason,
+ (0, CounterpartyForceClosed) => { (1, peer_msg, required) },
+ (1, FundingTimedOut) => {},
+ (2, HolderForceClosed) => {},
+ (6, CommitmentTxConfirmed) => {},
+ (4, CooperativeClosure) => {},
+ (8, ProcessingError) => { (1, err, required) },
+ (10, DisconnectedPeer) => {},
+ (12, OutdatedChannelManager) => {},
+);
+
+/// Intended destination of a failed HTLC as indicated in [`Event::HTLCHandlingFailed`].
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum HTLCDestination {
+ /// We tried forwarding to a channel but failed to do so. An example of such an instance is when
+ /// there is insufficient capacity in our outbound channel.
+ NextHopChannel {
+ /// The `node_id` of the next node. For backwards compatibility, this field is
+ /// marked as optional, versions prior to 0.0.110 may not always be able to provide
+ /// counterparty node information.
+ node_id: Option<PublicKey>,
+ /// The outgoing `channel_id` between us and the next node.
+ channel_id: [u8; 32],
+ },
+ /// Scenario where we are unsure of the next node to forward the HTLC to.
+ UnknownNextHop {
+ /// Short channel id we are requesting to forward an HTLC to.
+ requested_forward_scid: u64,
+ },
+ /// Failure scenario where an HTLC may have been forwarded to be intended for us,
+ /// but is invalid for some reason, so we reject it.
+ ///
+ /// Some of the reasons may include:
+ /// * HTLC Timeouts
+ /// * Expected MPP amount to claim does not equal HTLC total
+ /// * Claimable amount does not match expected amount
+ FailedPayment {
+ /// The payment hash of the payment we attempted to process.
+ payment_hash: PaymentHash
+ },
+}
+
+impl_writeable_tlv_based_enum_upgradable!(HTLCDestination,
+ (0, NextHopChannel) => {
+ (0, node_id, required),
+ (2, channel_id, required),
+ },
+ (2, UnknownNextHop) => {
+ (0, requested_forward_scid, required),
+ },
+ (4, FailedPayment) => {
+ (0, payment_hash, required),
+ }
+);
+
+#[cfg(anchors)]
+/// A descriptor used to sign for a commitment transaction's anchor output.
+#[derive(Clone, Debug)]
+pub struct AnchorDescriptor {
+ /// A unique identifier used along with `channel_value_satoshis` to re-derive the
+ /// [`InMemorySigner`] required to sign `input`.
+ ///
+ /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
+ pub channel_keys_id: [u8; 32],
+ /// The value in satoshis of the channel we're attempting to spend the anchor output of. This is
+ /// used along with `channel_keys_id` to re-derive the [`InMemorySigner`] required to sign
+ /// `input`.
+ ///
+ /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
+ pub channel_value_satoshis: u64,
+ /// The transaction input's outpoint corresponding to the commitment transaction's anchor
+ /// output.
+ pub outpoint: OutPoint,
+}
+
+#[cfg(anchors)]
+/// Represents the different types of transactions, originating from LDK, to be bumped.
+#[derive(Clone, Debug)]
+pub enum BumpTransactionEvent {
+ /// Indicates that a channel featuring anchor outputs is to be closed by broadcasting the local
+ /// commitment transaction. Since commitment transactions have a static feerate pre-agreed upon,
+ /// they may need additional fees to be attached through a child transaction using the popular
+ /// [Child-Pays-For-Parent](https://bitcoinops.org/en/topics/cpfp) fee bumping technique. This
+ /// child transaction must include the anchor input described within `anchor_descriptor` along
+ /// with additional inputs to meet the target feerate. Failure to meet the target feerate
+ /// decreases the confirmation odds of the transaction package (which includes the commitment
+ /// and child anchor transactions), possibly resulting in a loss of funds. Once the transaction
+ /// is constructed, it must be fully signed for and broadcasted by the consumer of the event
+ /// along with the `commitment_tx` enclosed. Note that the `commitment_tx` must always be
+ /// broadcast first, as the child anchor transaction depends on it.
+ ///
+ /// The consumer should be able to sign for any of the additional inputs included within the
+ /// child anchor transaction. To sign its anchor input, an [`InMemorySigner`] should be
+ /// re-derived through [`KeysManager::derive_channel_keys`] with the help of
+ /// [`AnchorDescriptor::channel_keys_id`] and [`AnchorDescriptor::channel_value_satoshis`].
+ ///
+ /// It is possible to receive more than one instance of this event if a valid child anchor
+ /// transaction is never broadcast or is but not with a sufficient fee to be mined. Care should
+ /// be taken by the consumer of the event to ensure any future iterations of the child anchor
+ /// transaction adhere to the [Replace-By-Fee
+ /// rules](https://github.com/bitcoin/bitcoin/blob/master/doc/policy/mempool-replacements.md)
+ /// for fee bumps to be accepted into the mempool, and eventually the chain. As the frequency of
+ /// these events is not user-controlled, users may ignore/drop the event if they are no longer
+ /// able to commit external confirmed funds to the child anchor transaction.
+ ///
+ /// The set of `pending_htlcs` on the commitment transaction to be broadcast can be inspected to
+ /// determine whether a significant portion of the channel's funds are allocated to HTLCs,
+ /// enabling users to make their own decisions regarding the importance of the commitment
+ /// transaction's confirmation. Note that this is not required, but simply exists as an option
+ /// for users to override LDK's behavior. On commitments with no HTLCs (indicated by those with
+ /// an empty `pending_htlcs`), confirmation of the commitment transaction can be considered to
+ /// be not urgent.
+ ///
+ /// [`InMemorySigner`]: crate::chain::keysinterface::InMemorySigner
+ /// [`KeysManager::derive_channel_keys`]: crate::chain::keysinterface::KeysManager::derive_channel_keys
+ ChannelClose {
+ /// The target feerate that the transaction package, which consists of the commitment
+ /// transaction and the to-be-crafted child anchor transaction, must meet.
+ package_target_feerate_sat_per_1000_weight: u32,
+ /// The channel's commitment transaction to bump the fee of. This transaction should be
+ /// broadcast along with the anchor transaction constructed as a result of consuming this
+ /// event.
+ commitment_tx: Transaction,
+ /// The absolute fee in satoshis of the commitment transaction. This can be used along the
+ /// with weight of the commitment transaction to determine its feerate.
+ commitment_tx_fee_satoshis: u64,
+ /// The descriptor to sign the anchor input of the anchor transaction constructed as a
+ /// result of consuming this event.
+ anchor_descriptor: AnchorDescriptor,
+ /// The set of pending HTLCs on the commitment transaction that need to be resolved once the
+ /// commitment transaction confirms.
+ pending_htlcs: Vec<HTLCOutputInCommitment>,
+ },
+}