LocalRemoved(InboundHTLCRemovalReason),
}
+/// Exposes the state of pending inbound HTLCs.
+///
+/// At a high level, an HTLC being forwarded from one Lightning node to another Lightning node goes
+/// through the following states in the state machine:
+/// - Announced for addition by the originating node through the update_add_htlc message.
+/// - Added to the commitment transaction of the receiving node and originating node in turn
+/// through the exchange of commitment_signed and revoke_and_ack messages.
+/// - Announced for resolution (fulfillment or failure) by the receiving node through either one of
+/// the update_fulfill_htlc, update_fail_htlc, and update_fail_malformed_htlc messages.
+/// - Removed from the commitment transaction of the originating node and receiving node in turn
+/// through the exchange of commitment_signed and revoke_and_ack messages.
+///
+/// This can be used to inspect what next message an HTLC is waiting for to advance its state.
+#[derive(Clone, Debug, PartialEq)]
+pub enum InboundHTLCStateDetails {
+ /// We have added this HTLC in our commitment transaction by receiving commitment_signed and
+ /// returning revoke_and_ack. We are awaiting the appropriate revoke_and_ack's from the remote
+ /// before this HTLC is included on the remote commitment transaction.
+ AwaitingRemoteRevokeToAdd,
+ /// This HTLC has been included in the commitment_signed and revoke_and_ack messages on both sides
+ /// and is included in both commitment transactions.
+ ///
+ /// This HTLC is now safe to either forward or be claimed as a payment by us. The HTLC will
+ /// remain in this state until the forwarded upstream HTLC has been resolved and we resolve this
+ /// HTLC correspondingly, or until we claim it as a payment. If it is part of a multipart
+ /// payment, it will only be claimed together with other required parts.
+ Committed,
+ /// We have received the preimage for this HTLC and it is being removed by fulfilling it with
+ /// update_fulfill_htlc. This HTLC is still on both commitment transactions, but we are awaiting
+ /// the appropriate revoke_and_ack's from the remote before this HTLC is removed from the remote
+ /// commitment transaction after update_fulfill_htlc.
+ AwaitingRemoteRevokeToRemoveFulfill,
+ /// The HTLC is being removed by failing it with update_fail_htlc or update_fail_malformed_htlc.
+ /// This HTLC is still on both commitment transactions, but we are awaiting the appropriate
+ /// revoke_and_ack's from the remote before this HTLC is removed from the remote commitment
+ /// transaction.
+ AwaitingRemoteRevokeToRemoveFail,
+}
+
+impl From<&InboundHTLCState> for Option<InboundHTLCStateDetails> {
+ fn from(state: &InboundHTLCState) -> Option<InboundHTLCStateDetails> {
+ match state {
+ InboundHTLCState::RemoteAnnounced(_) => None,
+ InboundHTLCState::AwaitingRemoteRevokeToAnnounce(_) =>
+ Some(InboundHTLCStateDetails::AwaitingRemoteRevokeToAdd),
+ InboundHTLCState::AwaitingAnnouncedRemoteRevoke(_) =>
+ Some(InboundHTLCStateDetails::AwaitingRemoteRevokeToAdd),
+ InboundHTLCState::Committed =>
+ Some(InboundHTLCStateDetails::Committed),
+ InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailRelay(_)) =>
+ Some(InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFail),
+ InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::FailMalformed(_)) =>
+ Some(InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFail),
+ InboundHTLCState::LocalRemoved(InboundHTLCRemovalReason::Fulfill(_)) =>
+ Some(InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFulfill),
+ }
+ }
+}
+
+impl_writeable_tlv_based_enum_upgradable!(InboundHTLCStateDetails,
+ (0, AwaitingRemoteRevokeToAdd) => {},
+ (2, Committed) => {},
+ (4, AwaitingRemoteRevokeToRemoveFulfill) => {},
+ (6, AwaitingRemoteRevokeToRemoveFail) => {};
+);
+
struct InboundHTLCOutput {
htlc_id: u64,
amount_msat: u64,
state: InboundHTLCState,
}
+/// Exposes details around pending inbound HTLCs.
+#[derive(Clone, Debug, PartialEq)]
+pub struct InboundHTLCDetails {
+ /// The HTLC ID.
+ /// The IDs are incremented by 1 starting from 0 for each offered HTLC.
+ /// They are unique per channel and inbound/outbound direction, unless an HTLC was only announced
+ /// and not part of any commitment transaction.
+ pub htlc_id: u64,
+ /// The amount in msat.
+ pub amount_msat: u64,
+ /// The block height at which this HTLC expires.
+ pub cltv_expiry: u32,
+ /// The payment hash.
+ pub payment_hash: PaymentHash,
+ /// The state of the HTLC in the state machine.
+ /// Determines on which commitment transactions the HTLC is included and what message the HTLC is
+ /// waiting for to advance to the next state.
+ /// See [`InboundHTLCStateDetails`] for information on the specific states.
+ pub state: Option<InboundHTLCStateDetails>,
+ /// Whether the HTLC has an output below the local dust limit. If so, the output will be trimmed
+ /// from the local commitment transaction and added to the commitment transaction fee.
+ /// For non-anchor channels, this takes into account the cost of the second-stage HTLC
+ /// transactions as well.
+ ///
+ /// When the local commitment transaction is broadcasted as part of a unilateral closure,
+ /// the value of this HTLC will therefore not be claimable but instead burned as a transaction
+ /// fee.
+ ///
+ /// Note that dust limits are specific to each party. An HTLC can be dust for the local
+ /// commitment transaction but not for the counterparty's commitment transaction and vice versa.
+ pub is_dust: bool,
+}
+
+impl_writeable_tlv_based!(InboundHTLCDetails, {
+ (0, htlc_id, required),
+ (2, amount_msat, required),
+ (4, cltv_expiry, required),
+ (6, payment_hash, required),
+ (7, state, upgradable_option),
+ (8, is_dust, required),
+});
+
#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
enum OutboundHTLCState {
/// Added by us and included in a commitment_signed (if we were AwaitingRemoteRevoke when we
AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome),
}
+/// Exposes the state of pending outbound HTLCs.
+///
+/// At a high level, an HTLC being forwarded from one Lightning node to another Lightning node goes
+/// through the following states in the state machine:
+/// - Announced for addition by the originating node through the update_add_htlc message.
+/// - Added to the commitment transaction of the receiving node and originating node in turn
+/// through the exchange of commitment_signed and revoke_and_ack messages.
+/// - Announced for resolution (fulfillment or failure) by the receiving node through either one of
+/// the update_fulfill_htlc, update_fail_htlc, and update_fail_malformed_htlc messages.
+/// - Removed from the commitment transaction of the originating node and receiving node in turn
+/// through the exchange of commitment_signed and revoke_and_ack messages.
+///
+/// This can be used to inspect what next message an HTLC is waiting for to advance its state.
+#[derive(Clone, Debug, PartialEq)]
+pub enum OutboundHTLCStateDetails {
+ /// We are awaiting the appropriate revoke_and_ack's from the remote before the HTLC is added
+ /// on the remote's commitment transaction after update_add_htlc.
+ AwaitingRemoteRevokeToAdd,
+ /// The HTLC has been added to the remote's commitment transaction by sending commitment_signed
+ /// and receiving revoke_and_ack in return.
+ ///
+ /// The HTLC will remain in this state until the remote node resolves the HTLC, or until we
+ /// unilaterally close the channel due to a timeout with an uncooperative remote node.
+ Committed,
+ /// The HTLC has been fulfilled successfully by the remote with a preimage in update_fulfill_htlc,
+ /// and we removed the HTLC from our commitment transaction by receiving commitment_signed and
+ /// returning revoke_and_ack. We are awaiting the appropriate revoke_and_ack's from the remote
+ /// for the removal from its commitment transaction.
+ AwaitingRemoteRevokeToRemoveSuccess,
+ /// The HTLC has been failed by the remote with update_fail_htlc or update_fail_malformed_htlc,
+ /// and we removed the HTLC from our commitment transaction by receiving commitment_signed and
+ /// returning revoke_and_ack. We are awaiting the appropriate revoke_and_ack's from the remote
+ /// for the removal from its commitment transaction.
+ AwaitingRemoteRevokeToRemoveFailure,
+}
+
+impl From<&OutboundHTLCState> for OutboundHTLCStateDetails {
+ fn from(state: &OutboundHTLCState) -> OutboundHTLCStateDetails {
+ match state {
+ OutboundHTLCState::LocalAnnounced(_) =>
+ OutboundHTLCStateDetails::AwaitingRemoteRevokeToAdd,
+ OutboundHTLCState::Committed =>
+ OutboundHTLCStateDetails::Committed,
+ // RemoteRemoved states are ignored as the state is transient and the remote has not committed to
+ // the state yet.
+ OutboundHTLCState::RemoteRemoved(_) =>
+ OutboundHTLCStateDetails::Committed,
+ OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Success(_)) =>
+ OutboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveSuccess,
+ OutboundHTLCState::AwaitingRemoteRevokeToRemove(OutboundHTLCOutcome::Failure(_)) =>
+ OutboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFailure,
+ OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Success(_)) =>
+ OutboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveSuccess,
+ OutboundHTLCState::AwaitingRemovedRemoteRevoke(OutboundHTLCOutcome::Failure(_)) =>
+ OutboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFailure,
+ }
+ }
+}
+
+impl_writeable_tlv_based_enum_upgradable!(OutboundHTLCStateDetails,
+ (0, AwaitingRemoteRevokeToAdd) => {},
+ (2, Committed) => {},
+ (4, AwaitingRemoteRevokeToRemoveSuccess) => {},
+ (6, AwaitingRemoteRevokeToRemoveFailure) => {};
+);
+
#[derive(Clone)]
#[cfg_attr(test, derive(Debug, PartialEq))]
enum OutboundHTLCOutcome {
skimmed_fee_msat: Option<u64>,
}
+/// Exposes details around pending outbound HTLCs.
+#[derive(Clone, Debug, PartialEq)]
+pub struct OutboundHTLCDetails {
+ /// The HTLC ID.
+ /// The IDs are incremented by 1 starting from 0 for each offered HTLC.
+ /// They are unique per channel and inbound/outbound direction, unless an HTLC was only announced
+ /// and not part of any commitment transaction.
+ ///
+ /// Not present when we are awaiting a remote revocation and the HTLC is not added yet.
+ pub htlc_id: Option<u64>,
+ /// The amount in msat.
+ pub amount_msat: u64,
+ /// The block height at which this HTLC expires.
+ pub cltv_expiry: u32,
+ /// The payment hash.
+ pub payment_hash: PaymentHash,
+ /// The state of the HTLC in the state machine.
+ /// Determines on which commitment transactions the HTLC is included and what message the HTLC is
+ /// waiting for to advance to the next state.
+ /// See [`OutboundHTLCStateDetails`] for information on the specific states.
+ pub state: Option<OutboundHTLCStateDetails>,
+ /// The extra fee being skimmed off the top of this HTLC.
+ pub skimmed_fee_msat: Option<u64>,
+ /// Whether the HTLC has an output below the local dust limit. If so, the output will be trimmed
+ /// from the local commitment transaction and added to the commitment transaction fee.
+ /// For non-anchor channels, this takes into account the cost of the second-stage HTLC
+ /// transactions as well.
+ ///
+ /// When the local commitment transaction is broadcasted as part of a unilateral closure,
+ /// the value of this HTLC will therefore not be claimable but instead burned as a transaction
+ /// fee.
+ ///
+ /// Note that dust limits are specific to each party. An HTLC can be dust for the local
+ /// commitment transaction but not for the counterparty's commitment transaction and vice versa.
+ pub is_dust: bool,
+}
+
+impl_writeable_tlv_based!(OutboundHTLCDetails, {
+ (0, htlc_id, required),
+ (2, amount_msat, required),
+ (4, cltv_expiry, required),
+ (6, payment_hash, required),
+ (7, state, upgradable_option),
+ (8, skimmed_fee_msat, required),
+ (10, is_dust, required),
+});
+
/// See AwaitingRemoteRevoke ChannelState for more info
#[cfg_attr(test, derive(Clone, Debug, PartialEq))]
enum HTLCUpdateAwaitingACK {
stats
}
+ /// Returns information on all pending inbound HTLCs.
+ pub fn get_pending_inbound_htlc_details(&self) -> Vec<InboundHTLCDetails> {
+ let mut holding_cell_states = new_hash_map();
+ for holding_cell_update in self.holding_cell_htlc_updates.iter() {
+ match holding_cell_update {
+ HTLCUpdateAwaitingACK::ClaimHTLC { htlc_id, .. } => {
+ holding_cell_states.insert(
+ htlc_id,
+ InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFulfill,
+ );
+ },
+ HTLCUpdateAwaitingACK::FailHTLC { htlc_id, .. } => {
+ holding_cell_states.insert(
+ htlc_id,
+ InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFail,
+ );
+ },
+ HTLCUpdateAwaitingACK::FailMalformedHTLC { htlc_id, .. } => {
+ holding_cell_states.insert(
+ htlc_id,
+ InboundHTLCStateDetails::AwaitingRemoteRevokeToRemoveFail,
+ );
+ },
+ // Outbound HTLC.
+ HTLCUpdateAwaitingACK::AddHTLC { .. } => {},
+ }
+ }
+ let mut inbound_details = Vec::new();
+ let htlc_success_dust_limit = if self.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+ 0
+ } else {
+ let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64;
+ dust_buffer_feerate * htlc_success_tx_weight(self.get_channel_type()) / 1000
+ };
+ let holder_dust_limit_success_sat = htlc_success_dust_limit + self.holder_dust_limit_satoshis;
+ for htlc in self.pending_inbound_htlcs.iter() {
+ if let Some(state_details) = (&htlc.state).into() {
+ inbound_details.push(InboundHTLCDetails{
+ htlc_id: htlc.htlc_id,
+ amount_msat: htlc.amount_msat,
+ cltv_expiry: htlc.cltv_expiry,
+ payment_hash: htlc.payment_hash,
+ state: Some(holding_cell_states.remove(&htlc.htlc_id).unwrap_or(state_details)),
+ is_dust: htlc.amount_msat / 1000 < holder_dust_limit_success_sat,
+ });
+ }
+ }
+ inbound_details
+ }
+
+ /// Returns information on all pending outbound HTLCs.
+ pub fn get_pending_outbound_htlc_details(&self) -> Vec<OutboundHTLCDetails> {
+ let mut outbound_details = Vec::new();
+ let htlc_timeout_dust_limit = if self.get_channel_type().supports_anchors_zero_fee_htlc_tx() {
+ 0
+ } else {
+ let dust_buffer_feerate = self.get_dust_buffer_feerate(None) as u64;
+ dust_buffer_feerate * htlc_success_tx_weight(self.get_channel_type()) / 1000
+ };
+ let holder_dust_limit_timeout_sat = htlc_timeout_dust_limit + self.holder_dust_limit_satoshis;
+ for htlc in self.pending_outbound_htlcs.iter() {
+ outbound_details.push(OutboundHTLCDetails{
+ htlc_id: Some(htlc.htlc_id),
+ amount_msat: htlc.amount_msat,
+ cltv_expiry: htlc.cltv_expiry,
+ payment_hash: htlc.payment_hash,
+ skimmed_fee_msat: htlc.skimmed_fee_msat,
+ state: Some((&htlc.state).into()),
+ is_dust: htlc.amount_msat / 1000 < holder_dust_limit_timeout_sat,
+ });
+ }
+ for holding_cell_update in self.holding_cell_htlc_updates.iter() {
+ if let HTLCUpdateAwaitingACK::AddHTLC {
+ amount_msat,
+ cltv_expiry,
+ payment_hash,
+ skimmed_fee_msat,
+ ..
+ } = *holding_cell_update {
+ outbound_details.push(OutboundHTLCDetails{
+ htlc_id: None,
+ amount_msat: amount_msat,
+ cltv_expiry: cltv_expiry,
+ payment_hash: payment_hash,
+ skimmed_fee_msat: skimmed_fee_msat,
+ state: Some(OutboundHTLCStateDetails::AwaitingRemoteRevokeToAdd),
+ is_dust: amount_msat / 1000 < holder_dust_limit_timeout_sat,
+ });
+ }
+ }
+ outbound_details
+ }
+
/// Get the available balances, see [`AvailableBalances`]'s fields for more info.
/// Doesn't bother handling the
/// if-we-removed-it-already-but-haven't-fully-resolved-they-can-still-send-an-inbound-HTLC
projects / rust-lightning / blobdiff