use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
use bitcoin::secp256k1::{SecretKey, PublicKey};
-use bitcoin::secp256k1;
+use bitcoin::{secp256k1, EcdsaSighashType};
+use crate::ln::channel::INITIAL_COMMITMENT_NUMBER;
use crate::ln::{PaymentHash, PaymentPreimage};
use crate::ln::msgs::DecodeError;
use crate::ln::chan_utils;
/// The node_id of our counterparty
counterparty_node_id: Option<PublicKey>,
+
+ /// Initial counterparty commmitment data needed to recreate the commitment tx
+ /// in the persistence pipeline for third-party watchtowers. This will only be present on
+ /// monitors created after 0.0.117.
+ ///
+ /// Ordering of tuple data: (their_per_commitment_point, feerate_per_kw, to_broadcaster_sats,
+ /// to_countersignatory_sats)
+ initial_counterparty_commitment_info: Option<(PublicKey, u32, u64, u64)>,
}
/// Transaction outputs to watch for on-chain spends.
(11, self.confirmed_commitment_tx_counterparty_output, option),
(13, self.spendable_txids_confirmed, required_vec),
(15, self.counterparty_fulfilled_htlcs, required),
+ (17, self.initial_counterparty_commitment_info, option),
});
Ok(())
best_block,
counterparty_node_id: Some(counterparty_node_id),
+ initial_counterparty_commitment_info: None,
})
}
self.inner.lock().unwrap().provide_secret(idx, secret)
}
+ /// A variant of `Self::provide_latest_counterparty_commitment_tx` used to provide
+ /// additional information to the monitor to store in order to recreate the initial
+ /// counterparty commitment transaction during persistence (mainly for use in third-party
+ /// watchtowers).
+ ///
+ /// This is used to provide the counterparty commitment information directly to the monitor
+ /// before the initial persistence of a new channel.
+ pub(crate) fn provide_initial_counterparty_commitment_tx<L: Deref>(
+ &self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
+ commitment_number: u64, their_cur_per_commitment_point: PublicKey, feerate_per_kw: u32,
+ to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, logger: &L,
+ )
+ where L::Target: Logger
+ {
+ self.inner.lock().unwrap().provide_initial_counterparty_commitment_tx(txid,
+ htlc_outputs, commitment_number, their_cur_per_commitment_point, feerate_per_kw,
+ to_broadcaster_value_sat, to_countersignatory_value_sat, logger);
+ }
+
/// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
/// The monitor watches for it to be broadcasted and then uses the HTLC information (and
/// possibly future revocation/preimage information) to claim outputs where possible.
/// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
- pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
+ #[cfg(test)]
+ fn provide_latest_counterparty_commitment_tx<L: Deref>(
&self,
txid: Txid,
htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
ret
}
+ /// Gets the counterparty's initial commitment transaction. The returned commitment
+ /// transaction is unsigned. This is intended to be called during the initial persistence of
+ /// the monitor (inside an implementation of [`Persist::persist_new_channel`]), to allow for
+ /// watchtowers in the persistence pipeline to have enough data to form justice transactions.
+ ///
+ /// This is similar to [`Self::counterparty_commitment_txs_from_update`], except
+ /// that for the initial commitment transaction, we don't have a corresponding update.
+ ///
+ /// This will only return `Some` for channel monitors that have been created after upgrading
+ /// to LDK 0.0.117+.
+ ///
+ /// [`Persist::persist_new_channel`]: crate::chain::chainmonitor::Persist::persist_new_channel
+ pub fn initial_counterparty_commitment_tx(&self) -> Option<CommitmentTransaction> {
+ self.inner.lock().unwrap().initial_counterparty_commitment_tx()
+ }
+
/// Gets all of the counterparty commitment transactions provided by the given update. This
/// may be empty if the update doesn't include any new counterparty commitments. Returned
/// commitment transactions are unsigned.
/// This is provided so that watchtower clients in the persistence pipeline are able to build
/// justice transactions for each counterparty commitment upon each update. It's intended to be
/// used within an implementation of [`Persist::update_persisted_channel`], which is provided
- /// with a monitor and an update.
+ /// with a monitor and an update. Once revoked, signing a justice transaction can be done using
+ /// [`Self::sign_to_local_justice_tx`].
///
/// It is expected that a watchtower client may use this method to retrieve the latest counterparty
/// commitment transaction(s), and then hold the necessary data until a later update in which
self.inner.lock().unwrap().counterparty_commitment_txs_from_update(update)
}
+ /// Wrapper around [`EcdsaChannelSigner::sign_justice_revoked_output`] to make
+ /// signing the justice transaction easier for implementors of
+ /// [`chain::chainmonitor::Persist`]. On success this method returns the provided transaction
+ /// signing the input at `input_idx`. This method will only produce a valid signature for
+ /// a transaction spending the `to_local` output of a commitment transaction, i.e. this cannot
+ /// be used for revoked HTLC outputs.
+ ///
+ /// `Value` is the value of the output being spent by the input at `input_idx`, committed
+ /// in the BIP 143 signature.
+ ///
+ /// This method will only succeed if this monitor has received the revocation secret for the
+ /// provided `commitment_number`. If a commitment number is provided that does not correspond
+ /// to the commitment transaction being revoked, this will return a signed transaction, but
+ /// the signature will not be valid.
+ ///
+ /// [`EcdsaChannelSigner::sign_justice_revoked_output`]: crate::sign::EcdsaChannelSigner::sign_justice_revoked_output
+ /// [`Persist`]: crate::chain::chainmonitor::Persist
+ pub fn sign_to_local_justice_tx(&self, justice_tx: Transaction, input_idx: usize, value: u64, commitment_number: u64) -> Result<Transaction, ()> {
+ self.inner.lock().unwrap().sign_to_local_justice_tx(justice_tx, input_idx, value, commitment_number)
+ }
+
pub(crate) fn get_min_seen_secret(&self) -> u64 {
self.inner.lock().unwrap().get_min_seen_secret()
}
Ok(())
}
+ pub(crate) fn provide_initial_counterparty_commitment_tx<L: Deref>(
+ &mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
+ commitment_number: u64, their_per_commitment_point: PublicKey, feerate_per_kw: u32,
+ to_broadcaster_value: u64, to_countersignatory_value: u64, logger: &L
+ )
+ where L::Target: Logger
+ {
+ self.initial_counterparty_commitment_info = Some((their_per_commitment_point.clone(),
+ feerate_per_kw, to_broadcaster_value, to_countersignatory_value));
+
+ #[cfg(debug_assertions)] {
+ let rebuilt_commitment_tx = self.initial_counterparty_commitment_tx().unwrap();
+ debug_assert_eq!(rebuilt_commitment_tx.trust().txid(), txid);
+ }
+
+ self.provide_latest_counterparty_commitment_tx(txid, htlc_outputs, commitment_number,
+ their_per_commitment_point, logger);
+ }
+
pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(&mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_per_commitment_point: PublicKey, logger: &L) where L::Target: Logger {
// TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
// so that a remote monitor doesn't learn anything unless there is a malicious close.
}
} else if !self.holder_tx_signed {
log_error!(logger, "WARNING: You have a potentially-unsafe holder commitment transaction available to broadcast");
- log_error!(logger, " in channel monitor for channel {}!", log_bytes!(self.funding_info.0.to_channel_id()));
+ log_error!(logger, " in channel monitor for channel {}!", &self.funding_info.0.to_channel_id());
log_error!(logger, " Read the docs for ChannelMonitor::get_latest_holder_commitment_txn and take manual action!");
} else {
// If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
ret
}
+ pub(crate) fn initial_counterparty_commitment_tx(&mut self) -> Option<CommitmentTransaction> {
+ let (their_per_commitment_point, feerate_per_kw, to_broadcaster_value,
+ to_countersignatory_value) = self.initial_counterparty_commitment_info?;
+ let htlc_outputs = vec![];
+
+ let commitment_tx = self.build_counterparty_commitment_tx(INITIAL_COMMITMENT_NUMBER,
+ &their_per_commitment_point, to_broadcaster_value, to_countersignatory_value,
+ feerate_per_kw, htlc_outputs);
+ Some(commitment_tx)
+ }
+
fn build_counterparty_commitment_tx(
&self, commitment_number: u64, their_per_commitment_point: &PublicKey,
to_broadcaster_value: u64, to_countersignatory_value: u64, feerate_per_kw: u32,
}).collect()
}
+ pub(crate) fn sign_to_local_justice_tx(
+ &self, mut justice_tx: Transaction, input_idx: usize, value: u64, commitment_number: u64
+ ) -> Result<Transaction, ()> {
+ let secret = self.get_secret(commitment_number).ok_or(())?;
+ let per_commitment_key = SecretKey::from_slice(&secret).map_err(|_| ())?;
+ let their_per_commitment_point = PublicKey::from_secret_key(
+ &self.onchain_tx_handler.secp_ctx, &per_commitment_key);
+
+ let revocation_pubkey = chan_utils::derive_public_revocation_key(
+ &self.onchain_tx_handler.secp_ctx, &their_per_commitment_point,
+ &self.holder_revocation_basepoint);
+ let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
+ &their_per_commitment_point,
+ &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
+ let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
+ self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
+
+ let sig = self.onchain_tx_handler.signer.sign_justice_revoked_output(
+ &justice_tx, input_idx, value, &per_commitment_key, &self.onchain_tx_handler.secp_ctx)?;
+ justice_tx.input[input_idx].witness.push_bitcoin_signature(&sig.serialize_der(), EcdsaSighashType::All);
+ justice_tx.input[input_idx].witness.push(&[1u8]);
+ justice_tx.input[input_idx].witness.push(revokeable_redeemscript.as_bytes());
+ Ok(justice_tx)
+ }
+
/// Can only fail if idx is < get_min_seen_secret
fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
self.commitment_secrets.get_secret(idx)
if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
let mut balance_spendable_csv = None;
log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
- log_bytes!(self.funding_info.0.to_channel_id()), txid);
+ &self.funding_info.0.to_channel_id(), txid);
self.funding_spend_seen = true;
let mut commitment_tx_to_counterparty_output = None;
if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
let mut confirmed_commitment_tx_counterparty_output = None;
let mut spendable_txids_confirmed = Some(Vec::new());
let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
+ let mut initial_counterparty_commitment_info = None;
read_tlv_fields!(reader, {
(1, funding_spend_confirmed, option),
(3, htlcs_resolved_on_chain, optional_vec),
(11, confirmed_commitment_tx_counterparty_output, option),
(13, spendable_txids_confirmed, optional_vec),
(15, counterparty_fulfilled_htlcs, option),
+ (17, initial_counterparty_commitment_info, option),
});
Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
best_block,
counterparty_node_id,
+ initial_counterparty_commitment_info,
})))
}
}
projects / rust-lightning / blobdiff