use core::ops::Deref;
use sync::Mutex;
-/// An update generated by the underlying Channel itself which contains some new information the
-/// ChannelMonitor should be made aware of.
+/// An update generated by the underlying channel itself which contains some new information the
+/// [`ChannelMonitor`] should be made aware of.
+///
+/// Because this represents only a small number of updates to the underlying state, it is generally
+/// much smaller than a full [`ChannelMonitor`]. However, for large single commitment transaction
+/// updates (e.g. ones during which there are hundreds of HTLCs pending on the commitment
+/// transaction), a single update may reach upwards of 1 MiB in serialized size.
#[cfg_attr(any(test, fuzzing, feature = "_test_utils"), derive(PartialEq))]
#[derive(Clone)]
#[must_use]
/// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
/// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
/// likely to be claimed by our counterparty before we do.
- MaybeClaimableHTLCAwaitingTimeout {
- /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
- /// required to do so.
+ MaybeTimeoutClaimableHTLC {
+ /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
+ /// which will be required to do so.
claimable_amount_satoshis: u64,
/// The height at which we will be able to claim the balance if our counterparty has not
/// done so.
claimable_height: u32,
},
+ /// HTLCs which we received from our counterparty which are claimable with a preimage which we
+ /// do not currently have. This will only be claimable if we receive the preimage from the node
+ /// to which we forwarded this HTLC before the timeout.
+ MaybePreimageClaimableHTLC {
+ /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
+ /// which will be required to do so.
+ claimable_amount_satoshis: u64,
+ /// The height at which our counterparty will be able to claim the balance if we have not
+ /// yet received the preimage and claimed it ourselves.
+ expiry_height: u32,
+ },
/// The channel has been closed, and our counterparty broadcasted a revoked commitment
/// transaction.
///
/// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
#[derive(PartialEq)]
struct IrrevocablyResolvedHTLC {
- commitment_tx_output_idx: u32,
+ commitment_tx_output_idx: Option<u32>,
/// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
/// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
/// transaction.
payment_preimage: Option<PaymentPreimage>,
}
-impl_writeable_tlv_based!(IrrevocablyResolvedHTLC, {
- (0, commitment_tx_output_idx, required),
- (1, resolving_txid, option),
- (2, payment_preimage, option),
-});
+// In LDK versions prior to 0.0.111 commitment_tx_output_idx was not Option-al and
+// IrrevocablyResolvedHTLC objects only existed for non-dust HTLCs. This was a bug, but to maintain
+// backwards compatibility we must ensure we always write out a commitment_tx_output_idx field,
+// using `u32::max_value()` as a sentinal to indicate the HTLC was dust.
+impl Writeable for IrrevocablyResolvedHTLC {
+ fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
+ let mapped_commitment_tx_output_idx = self.commitment_tx_output_idx.unwrap_or(u32::max_value());
+ write_tlv_fields!(writer, {
+ (0, mapped_commitment_tx_output_idx, required),
+ (1, self.resolving_txid, option),
+ (2, self.payment_preimage, option),
+ });
+ Ok(())
+ }
+}
+
+impl Readable for IrrevocablyResolvedHTLC {
+ fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
+ let mut mapped_commitment_tx_output_idx = 0;
+ let mut resolving_txid = None;
+ let mut payment_preimage = None;
+ read_tlv_fields!(reader, {
+ (0, mapped_commitment_tx_output_idx, required),
+ (1, resolving_txid, option),
+ (2, payment_preimage, option),
+ });
+ Ok(Self {
+ commitment_tx_output_idx: if mapped_commitment_tx_output_idx == u32::max_value() { None } else { Some(mapped_commitment_tx_output_idx) },
+ resolving_txid,
+ payment_preimage,
+ })
+ }
+}
/// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
/// on-chain transactions to ensure no loss of funds occurs.
}
}
let htlc_resolved = self.htlcs_resolved_on_chain.iter()
- .find(|v| if v.commitment_tx_output_idx == htlc_commitment_tx_output_idx {
+ .find(|v| if v.commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) {
debug_assert!(htlc_spend_txid_opt.is_none());
htlc_spend_txid_opt = v.resolving_txid;
true
confirmation_height: conf_thresh,
});
} else {
- return Some(Balance::MaybeClaimableHTLCAwaitingTimeout {
+ return Some(Balance::MaybeTimeoutClaimableHTLC {
claimable_amount_satoshis: htlc.amount_msat / 1000,
claimable_height: htlc.cltv_expiry,
});
timeout_height: htlc.cltv_expiry,
});
}
+ } else if htlc_resolved.is_none() {
+ return Some(Balance::MaybePreimageClaimableHTLC {
+ claimable_amount_satoshis: htlc.amount_msat / 1000,
+ expiry_height: htlc.cltv_expiry,
+ });
}
None
}
for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
if htlc.transaction_output_index.is_none() { continue; }
if htlc.offered {
- res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
+ res.push(Balance::MaybeTimeoutClaimableHTLC {
claimable_amount_satoshis: htlc.amount_msat / 1000,
claimable_height: htlc.cltv_expiry,
});
} else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
+ } else {
+ // As long as the HTLC is still in our latest commitment state, treat
+ // it as potentially claimable, even if it has long-since expired.
+ res.push(Balance::MaybePreimageClaimableHTLC {
+ claimable_amount_satoshis: htlc.amount_msat / 1000,
+ expiry_height: htlc.cltv_expiry,
+ });
}
}
res.push(Balance::ClaimableOnChannelClose {
macro_rules! walk_htlcs {
($holder_commitment: expr, $htlc_iter: expr) => {
for (htlc, source) in $htlc_iter {
- if us.htlcs_resolved_on_chain.iter().any(|v| Some(v.commitment_tx_output_idx) == htlc.transaction_output_index) {
+ if us.htlcs_resolved_on_chain.iter().any(|v| v.commitment_tx_output_idx == htlc.transaction_output_index) {
// We should assert that funding_spend_confirmed is_some() here, but we
// have some unit tests which violate HTLC transaction CSVs entirely and
// would fail.
source: source.clone(),
htlc_value_satoshis,
}));
- if let Some(idx) = commitment_tx_output_idx {
- self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
- commitment_tx_output_idx: idx, resolving_txid: Some(entry.txid),
- payment_preimage: None,
- });
- }
+ self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
+ commitment_tx_output_idx, resolving_txid: Some(entry.txid),
+ payment_preimage: None,
+ });
},
OnchainEvent::MaturingOutput { descriptor } => {
log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
},
OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
- commitment_tx_output_idx, resolving_txid: Some(entry.txid),
+ commitment_tx_output_idx: Some(commitment_tx_output_idx), resolving_txid: Some(entry.txid),
payment_preimage: preimage,
});
},