//! spendable on-chain outputs which the user owns and is responsible for using just as any other
//! on-chain output which is theirs.
-use bitcoin::blockdata::transaction::{Transaction, OutPoint, TxOut, SigHashType};
+use bitcoin::blockdata::transaction::{Transaction, OutPoint, TxOut};
use bitcoin::blockdata::script::{Script, Builder};
use bitcoin::blockdata::opcodes;
use bitcoin::network::constants::Network;
/// Signs a transaction created by build_htlc_transaction. If the transaction is an
/// HTLC-Success transaction, preimage must be set!
/// TODO: should be merged with sign_local_commitment as a slice of HTLC transactions to sign
- fn sign_htlc_transaction<T: secp256k1::Signing>(&self, htlc_tx: &mut Transaction, their_sig: &Signature, preimage: &Option<PaymentPreimage>, htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey, per_commitment_point: &PublicKey, secp_ctx: &Secp256k1<T>);
-
+ fn sign_htlc_transaction<T: secp256k1::Signing>(&self, local_commitment_tx: &mut LocalCommitmentTransaction, htlc_index: u32, preimage: Option<PaymentPreimage>, local_csv: u16, secp_ctx: &Secp256k1<T>);
/// Create a signature for a (proposed) closing transaction.
///
/// Note that, due to rounding, there may be one "missing" satoshi, and either party may have
local_commitment_tx.add_local_sig(&self.funding_key, funding_redeemscript, channel_value_satoshis, secp_ctx);
}
- fn sign_htlc_transaction<T: secp256k1::Signing>(&self, htlc_tx: &mut Transaction, their_sig: &Signature, preimage: &Option<PaymentPreimage>, htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey, per_commitment_point: &PublicKey, secp_ctx: &Secp256k1<T>) {
- if htlc_tx.input.len() != 1 { return; }
- if htlc_tx.input[0].witness.len() != 0 { return; }
-
- let htlc_redeemscript = chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, a_htlc_key, b_htlc_key, revocation_key);
-
- if let Ok(our_htlc_key) = chan_utils::derive_private_key(secp_ctx, per_commitment_point, &self.htlc_base_key) {
- let sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]);
- let local_tx = PublicKey::from_secret_key(&secp_ctx, &our_htlc_key) == *a_htlc_key;
- let our_sig = secp_ctx.sign(&sighash, &our_htlc_key);
-
- htlc_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
-
- if local_tx { // b, then a
- htlc_tx.input[0].witness.push(their_sig.serialize_der().to_vec());
- htlc_tx.input[0].witness.push(our_sig.serialize_der().to_vec());
- } else {
- htlc_tx.input[0].witness.push(our_sig.serialize_der().to_vec());
- htlc_tx.input[0].witness.push(their_sig.serialize_der().to_vec());
- }
- htlc_tx.input[0].witness[1].push(SigHashType::All as u8);
- htlc_tx.input[0].witness[2].push(SigHashType::All as u8);
-
- if htlc.offered {
- htlc_tx.input[0].witness.push(Vec::new());
- assert!(preimage.is_none());
- } else {
- htlc_tx.input[0].witness.push(preimage.unwrap().0.to_vec());
- }
-
- htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec());
- } else { return; }
+ fn sign_htlc_transaction<T: secp256k1::Signing>(&self, local_commitment_tx: &mut LocalCommitmentTransaction, htlc_index: u32, preimage: Option<PaymentPreimage>, local_csv: u16, secp_ctx: &Secp256k1<T>) {
+ local_commitment_tx.add_htlc_sig(&self.htlc_base_key, htlc_index, preimage, local_csv, secp_ctx);
}
fn sign_closing_transaction<T: secp256k1::Signing>(&self, closing_tx: &Transaction, secp_ctx: &Secp256k1<T>) -> Result<Signature, ()> {
use bitcoin_hashes::hash160::Hash as Hash160;
use bitcoin_hashes::sha256d::Hash as Sha256dHash;
-use ln::channelmanager::PaymentHash;
+use ln::channelmanager::{PaymentHash, PaymentPreimage};
use ln::msgs::DecodeError;
use util::ser::{Readable, Writeable, Writer, WriterWriteAdaptor};
use util::byte_utils;
use secp256k1::{Secp256k1, Signature};
use secp256k1;
+use std::{cmp, mem};
+
+const MAX_ALLOC_SIZE: usize = 64*1024;
+
pub(super) const HTLC_SUCCESS_TX_WEIGHT: u64 = 703;
pub(super) const HTLC_TIMEOUT_TX_WEIGHT: u64 = 663;
/// to broadcast. Eventually this will require a signer which is possibly external, but for now we
/// just pass in the SecretKeys required.
pub struct LocalCommitmentTransaction {
- tx: Transaction
+ tx: Transaction,
+ //TODO: modify Channel methods to integrate HTLC material at LocalCommitmentTransaction generation to drop Option here
+ local_keys: Option<TxCreationKeys>,
+ feerate_per_kw: Option<u64>,
+ per_htlc: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<Transaction>)>
}
impl LocalCommitmentTransaction {
#[cfg(test)]
input: vec![dummy_input],
output: Vec::new(),
lock_time: 0,
- } }
+ },
+ local_keys: None,
+ feerate_per_kw: None,
+ per_htlc: Vec::new()
+ }
}
/// Generate a new LocalCommitmentTransaction based on a raw commitment transaction,
tx.input[0].witness.push(Vec::new());
}
- Self { tx }
+ Self { tx,
+ local_keys: None,
+ feerate_per_kw: None,
+ per_htlc: Vec::new()
+ }
}
/// Get the txid of the local commitment transaction contained in this
assert!(self.has_local_sig());
&self.tx
}
+
+ /// Set HTLC cache to generate any local HTLC transaction spending one of htlc ouput
+ /// from this local commitment transaction
+ pub(crate) fn set_htlc_cache(&mut self, local_keys: TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<Transaction>)>) {
+ self.local_keys = Some(local_keys);
+ self.feerate_per_kw = Some(feerate_per_kw);
+ self.per_htlc = htlc_outputs;
+ }
+
+ /// Add local signature for a htlc transaction, do nothing if a cached signed transaction is
+ /// already present
+ pub fn add_htlc_sig<T: secp256k1::Signing>(&mut self, htlc_base_key: &SecretKey, htlc_index: u32, preimage: Option<PaymentPreimage>, local_csv: u16, secp_ctx: &Secp256k1<T>) {
+ if self.local_keys.is_none() || self.feerate_per_kw.is_none() { return; }
+ let local_keys = self.local_keys.as_ref().unwrap();
+ let txid = self.txid();
+ for this_htlc in self.per_htlc.iter_mut() {
+ if this_htlc.0.transaction_output_index.unwrap() == htlc_index {
+ if this_htlc.2.is_some() { return; } // we already have a cached htlc transaction at provided index
+ let mut htlc_tx = build_htlc_transaction(&txid, self.feerate_per_kw.unwrap(), local_csv, &this_htlc.0, &local_keys.a_delayed_payment_key, &local_keys.revocation_key);
+ if !this_htlc.0.offered && preimage.is_none() { return; } // if we don't have preimage for HTLC-Success, don't try to generate
+ let htlc_secret = if !this_htlc.0.offered { preimage } else { None }; // if we have a preimage for HTLC-Timeout, don't use it that's likely a duplicate HTLC hash
+ if this_htlc.1.is_none() { return; } // we don't have any remote signature for this htlc
+ if htlc_tx.input.len() != 1 { return; }
+ if htlc_tx.input[0].witness.len() != 0 { return; }
+
+ let htlc_redeemscript = get_htlc_redeemscript_with_explicit_keys(&this_htlc.0, &local_keys.a_htlc_key, &local_keys.b_htlc_key, &local_keys.revocation_key);
+
+ if let Ok(our_htlc_key) = derive_private_key(secp_ctx, &local_keys.per_commitment_point, htlc_base_key) {
+ let sighash = hash_to_message!(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, this_htlc.0.amount_msat / 1000)[..]);
+ let our_sig = secp_ctx.sign(&sighash, &our_htlc_key);
+
+ htlc_tx.input[0].witness.push(Vec::new()); // First is the multisig dummy
+
+ htlc_tx.input[0].witness.push(this_htlc.1.unwrap().serialize_der().to_vec());
+ htlc_tx.input[0].witness.push(our_sig.serialize_der().to_vec());
+ htlc_tx.input[0].witness[1].push(SigHashType::All as u8);
+ htlc_tx.input[0].witness[2].push(SigHashType::All as u8);
+
+ if this_htlc.0.offered {
+ htlc_tx.input[0].witness.push(Vec::new());
+ assert!(htlc_secret.is_none());
+ } else {
+ htlc_tx.input[0].witness.push(htlc_secret.unwrap().0.to_vec());
+ }
+
+ htlc_tx.input[0].witness.push(htlc_redeemscript.as_bytes().to_vec());
+
+ this_htlc.2 = Some(htlc_tx);
+ } else { return; }
+ }
+ }
+ }
+ /// Expose raw htlc transaction, guarante witness is complete if non-empty
+ pub fn htlc_with_valid_witness(&self, htlc_index: u32) -> &Option<Transaction> {
+ for this_htlc in self.per_htlc.iter() {
+ if this_htlc.0.transaction_output_index.unwrap() == htlc_index {
+ return &this_htlc.2;
+ }
+ }
+ &None
+ }
}
impl PartialEq for LocalCommitmentTransaction {
// We dont care whether we are signed in equality comparison
_ => panic!("local tx must have been well-formed!"),
}
}
+ self.local_keys.write(writer)?;
+ self.feerate_per_kw.write(writer)?;
+ writer.write_all(&byte_utils::be64_to_array(self.per_htlc.len() as u64))?;
+ for &(ref htlc, ref sig, ref htlc_tx) in self.per_htlc.iter() {
+ htlc.write(writer)?;
+ sig.write(writer)?;
+ htlc_tx.write(writer)?;
+ }
Ok(())
}
}
_ => return Err(DecodeError::InvalidValue),
},
};
+ let local_keys = Readable::read(reader)?;
+ let feerate_per_kw = Readable::read(reader)?;
+ let htlcs_count: u64 = Readable::read(reader)?;
+ let mut per_htlc = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / mem::size_of::<(HTLCOutputInCommitment, Option<Signature>, Option<Transaction>)>()));
+ for _ in 0..htlcs_count {
+ let htlc: HTLCOutputInCommitment = Readable::read(reader)?;
+ let sigs = Readable::read(reader)?;
+ let htlc_tx = Readable::read(reader)?;
+ per_htlc.push((htlc, sigs, htlc_tx));
+ }
if tx.input.len() != 1 {
// Ensure tx didn't hit the 0-input ambiguity case.
return Err(DecodeError::InvalidValue);
}
- Ok(Self { tx })
+ Ok(Self {
+ tx,
+ local_keys,
+ feerate_per_kw,
+ per_htlc,
+ })
}
}
let mut unsigned_tx: (Transaction, Vec<HTLCOutputInCommitment>);
+ let mut localtx;
macro_rules! test_commitment {
( $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
unsigned_tx = {
let sighash = Message::from_slice(&bip143::SighashComponents::new(&unsigned_tx.0).sighash_all(&unsigned_tx.0.input[0], &redeemscript, chan.channel_value_satoshis)[..]).unwrap();
secp_ctx.verify(&sighash, &their_signature, chan.their_funding_pubkey()).unwrap();
- let mut localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey());
+ localtx = LocalCommitmentTransaction::new_missing_local_sig(unsigned_tx.0.clone(), &their_signature, &PublicKey::from_secret_key(&secp_ctx, chan.local_keys.funding_key()), chan.their_funding_pubkey());
chan_keys.sign_local_commitment(&mut localtx, &redeemscript, chan.channel_value_satoshis, &chan.secp_ctx);
assert_eq!(serialize(localtx.with_valid_witness())[..],
}
macro_rules! test_htlc_output {
- ( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr ) => {
+ ( $htlc_idx: expr, $their_sig_hex: expr, $our_sig_hex: expr, $tx_hex: expr) => {
let remote_signature = Signature::from_der(&hex::decode($their_sig_hex).unwrap()[..]).unwrap();
let ref htlc = unsigned_tx.1[$htlc_idx];
- let mut htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
+ let htlc_tx = chan.build_htlc_transaction(&unsigned_tx.0.txid(), &htlc, true, &keys, chan.feerate_per_kw);
let htlc_redeemscript = chan_utils::get_htlc_redeemscript(&htlc, &keys);
let htlc_sighash = Message::from_slice(&bip143::SighashComponents::new(&htlc_tx).sighash_all(&htlc_tx.input[0], &htlc_redeemscript, htlc.amount_msat / 1000)[..]).unwrap();
secp_ctx.verify(&htlc_sighash, &remote_signature, &keys.b_htlc_key).unwrap();
assert!(preimage.is_some());
}
- chan_keys.sign_htlc_transaction(&mut htlc_tx, &remote_signature, &preimage, &htlc, &keys.a_htlc_key, &keys.b_htlc_key, &keys.revocation_key, &keys.per_commitment_point, &chan.secp_ctx);
- assert_eq!(serialize(&htlc_tx)[..],
+ let mut per_htlc = Vec::new();
+ per_htlc.push((htlc.clone(), Some(remote_signature), None));
+ localtx.set_htlc_cache(keys.clone(), chan.feerate_per_kw, per_htlc);
+ chan_keys.sign_htlc_transaction(&mut localtx, $htlc_idx, preimage, chan.their_to_self_delay, &chan.secp_ctx);
+
+ assert_eq!(serialize(localtx.htlc_with_valid_witness($htlc_idx).as_ref().unwrap())[..],
hex::decode($tx_hex).unwrap()[..]);
};
}
struct LocalSignedTx {
/// txid of the transaction in tx, just used to make comparison faster
txid: Sha256dHash,
- tx: LocalCommitmentTransaction,
revocation_key: PublicKey,
a_htlc_key: PublicKey,
b_htlc_key: PublicKey,
locktime: u32,
},
LocalHTLC {
- witness_script: Script,
- sigs: (Signature, Signature),
preimage: Option<PaymentPreimage>,
amount: u64,
},
writer.write_all(&byte_utils::be64_to_array(*amount))?;
writer.write_all(&byte_utils::be32_to_array(*locktime))?;
},
- &InputMaterial::LocalHTLC { ref witness_script, ref sigs, ref preimage, ref amount } => {
+ &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
writer.write_all(&[2; 1])?;
- witness_script.write(writer)?;
- sigs.0.write(writer)?;
- sigs.1.write(writer)?;
preimage.write(writer)?;
writer.write_all(&byte_utils::be64_to_array(*amount))?;
},
}
},
2 => {
- let witness_script = Readable::read(reader)?;
- let their_sig = Readable::read(reader)?;
- let our_sig = Readable::read(reader)?;
let preimage = Readable::read(reader)?;
let amount = Readable::read(reader)?;
InputMaterial::LocalHTLC {
- witness_script,
- sigs: (their_sig, our_sig),
preimage,
- amount
+ amount,
}
},
3 => {
macro_rules! serialize_local_tx {
($local_tx: expr) => {
- $local_tx.tx.write(writer)?;
+ $local_tx.txid.write(writer)?;
writer.write_all(&$local_tx.revocation_key.serialize())?;
writer.write_all(&$local_tx.a_htlc_key.serialize())?;
writer.write_all(&$local_tx.b_htlc_key.serialize())?;
/// is important that any clones of this channel monitor (including remote clones) by kept
/// up-to-date as our local commitment transaction is updated.
/// Panics if set_their_to_self_delay has never been called.
- pub(super) fn provide_latest_local_commitment_tx_info(&mut self, commitment_tx: LocalCommitmentTransaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
+ pub(super) fn provide_latest_local_commitment_tx_info(&mut self, mut commitment_tx: LocalCommitmentTransaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
if self.their_to_self_delay.is_none() {
return Err(MonitorUpdateError("Got a local commitment tx info update before we'd set basic information about the channel"));
}
+ let txid = commitment_tx.txid();
+ let sequence = commitment_tx.without_valid_witness().input[0].sequence as u64;
+ let locktime = commitment_tx.without_valid_witness().lock_time as u64;
+ let mut htlcs = Vec::with_capacity(htlc_outputs.len());
+ for htlc in htlc_outputs.clone() {
+ if let Some(_) = htlc.0.transaction_output_index {
+ htlcs.push((htlc.0, htlc.1, None));
+ }
+ }
+ commitment_tx.set_htlc_cache(local_keys.clone(), feerate_per_kw, htlcs);
// Returning a monitor error before updating tracking points means in case of using
// a concurrent watchtower implementation for same channel, if this one doesn't
// reject update as we do, you MAY have the latest local valid commitment tx onchain
// for which you want to spend outputs. We're NOT robust again this scenario right
// now but we should consider it later.
- if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx.clone(), local_keys.clone(), feerate_per_kw, htlc_outputs.clone()) {
+ if let Err(_) = self.onchain_tx_handler.provide_latest_local_tx(commitment_tx) {
return Err(MonitorUpdateError("Local commitment signed has already been signed, no further update of LOCAL commitment transaction is allowed"));
}
- self.current_local_commitment_number = 0xffff_ffff_ffff - ((((commitment_tx.without_valid_witness().input[0].sequence as u64 & 0xffffff) << 3*8) | (commitment_tx.without_valid_witness().lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
+ self.current_local_commitment_number = 0xffff_ffff_ffff - ((((sequence & 0xffffff) << 3*8) | (locktime as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
self.prev_local_signed_commitment_tx = self.current_local_signed_commitment_tx.take();
self.current_local_signed_commitment_tx = Some(LocalSignedTx {
- txid: commitment_tx.txid(),
- tx: commitment_tx,
+ txid,
revocation_key: local_keys.revocation_key,
a_htlc_key: local_keys.a_htlc_key,
b_htlc_key: local_keys.b_htlc_key,
(claimable_outpoints, Some((htlc_txid, tx.output.clone())))
}
- fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<Transaction>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
- let mut res = Vec::with_capacity(local_tx.htlc_outputs.len());
+ fn broadcast_by_local_state(&self, commitment_tx: &Transaction, local_tx: &LocalSignedTx) -> (Vec<ClaimRequest>, Vec<TxOut>, Option<(Script, SecretKey, Script)>) {
+ let mut claim_requests = Vec::with_capacity(local_tx.htlc_outputs.len());
let mut watch_outputs = Vec::with_capacity(local_tx.htlc_outputs.len());
let redeemscript = chan_utils::get_revokeable_redeemscript(&local_tx.revocation_key, self.their_to_self_delay.unwrap(), &local_tx.delayed_payment_key);
Some((redeemscript.to_v0_p2wsh(), local_delayedkey, redeemscript))
} else { None };
- for &(ref htlc, ref sigs, _) in local_tx.htlc_outputs.iter() {
+ for &(ref htlc, _, _) in local_tx.htlc_outputs.iter() {
if let Some(transaction_output_index) = htlc.transaction_output_index {
- if let &Some(ref their_sig) = sigs {
- if htlc.offered {
- log_trace!(self, "Broadcasting HTLC-Timeout transaction against local commitment transactions");
- let mut htlc_timeout_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
- self.onchain_detection.keys.sign_htlc_transaction(&mut htlc_timeout_tx, their_sig, &None, htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key, &local_tx.per_commitment_point, &self.secp_ctx);
-
- log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_timeout_tx.input[0].previous_output.vout, htlc_timeout_tx.input[0].previous_output.txid);
- res.push(htlc_timeout_tx);
- } else {
- if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
- log_trace!(self, "Broadcasting HTLC-Success transaction against local commitment transactions");
- let mut htlc_success_tx = chan_utils::build_htlc_transaction(&local_tx.txid, local_tx.feerate_per_kw, self.their_to_self_delay.unwrap(), htlc, &local_tx.delayed_payment_key, &local_tx.revocation_key);
- self.onchain_detection.keys.sign_htlc_transaction(&mut htlc_success_tx, their_sig, &Some(*payment_preimage), htlc, &local_tx.a_htlc_key, &local_tx.b_htlc_key, &local_tx.revocation_key, &local_tx.per_commitment_point, &self.secp_ctx);
-
- log_trace!(self, "Outpoint {}:{} is being being claimed", htlc_success_tx.input[0].previous_output.vout, htlc_success_tx.input[0].previous_output.txid);
- res.push(htlc_success_tx);
- }
- }
- watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
- } else { panic!("Should have sigs for non-dust local tx outputs!") }
+ let preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) { Some(*preimage) } else { None };
+ claim_requests.push(ClaimRequest { absolute_timelock: ::std::u32::MAX, aggregable: false, outpoint: BitcoinOutPoint { txid: local_tx.txid, vout: transaction_output_index as u32 }, witness_data: InputMaterial::LocalHTLC { preimage, amount: htlc.amount_msat / 1000 }});
+ watch_outputs.push(commitment_tx.output[transaction_output_index as usize].clone());
}
}
- (res, watch_outputs, broadcasted_local_revokable_script)
+ (claim_requests, watch_outputs, broadcasted_local_revokable_script)
}
/// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
/// revoked using data in local_claimable_outpoints.
/// Should not be used if check_spend_revoked_transaction succeeds.
- fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<Transaction>, (Sha256dHash, Vec<TxOut>)) {
+ fn check_spend_local_transaction(&mut self, tx: &Transaction, height: u32) -> (Vec<ClaimRequest>, (Sha256dHash, Vec<TxOut>)) {
let commitment_txid = tx.txid();
- let mut local_txn = Vec::new();
+ let mut claim_requests = Vec::new();
let mut watch_outputs = Vec::new();
macro_rules! wait_threshold_conf {
macro_rules! append_onchain_update {
($updates: expr) => {
- local_txn.append(&mut $updates.0);
+ claim_requests = $updates.0;
watch_outputs.append(&mut $updates.1);
self.broadcasted_local_revokable_script = $updates.2;
}
}
}
- (local_txn, (commitment_txid, watch_outputs))
+ (claim_requests, (commitment_txid, watch_outputs))
}
/// Used by ChannelManager deserialization to broadcast the latest local state if its copy of
watch_outputs.push(new_outputs);
}
if new_outpoints.is_empty() {
- let (local_txn, new_outputs) = self.check_spend_local_transaction(&tx, height);
- for tx in local_txn.iter() {
- log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
- broadcaster.broadcast_transaction(tx);
- }
+ let (mut new_outpoints, new_outputs) = self.check_spend_local_transaction(&tx, height);
if !new_outputs.1.is_empty() {
watch_outputs.push(new_outputs);
}
+ claimable_outpoints.append(&mut new_outpoints);
}
claimable_outpoints.append(&mut new_outpoints);
}
if let Some(ref cur_local_tx) = self.current_local_signed_commitment_tx {
if should_broadcast {
if let Some(commitment_tx) = self.onchain_tx_handler.get_fully_signed_local_tx(self.channel_value_satoshis.unwrap()) {
- let (txs, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, cur_local_tx);
+ let (mut new_outpoints, new_outputs, _) = self.broadcast_by_local_state(&commitment_tx, cur_local_tx);
if !new_outputs.is_empty() {
watch_outputs.push((cur_local_tx.txid.clone(), new_outputs));
}
- for tx in txs {
- log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
- broadcaster.broadcast_transaction(&tx);
- }
+ claimable_outpoints.append(&mut new_outpoints);
}
}
}
macro_rules! read_local_tx {
() => {
{
- let tx = <LocalCommitmentTransaction as Readable>::read(reader)?;
+ let txid = Readable::read(reader)?;
let revocation_key = Readable::read(reader)?;
let a_htlc_key = Readable::read(reader)?;
let b_htlc_key = Readable::read(reader)?;
}
LocalSignedTx {
- txid: tx.txid(),
- tx,
+ txid,
revocation_key, a_htlc_key, b_htlc_key, delayed_payment_key, per_commitment_point, feerate_per_kw,
htlc_outputs: htlcs
}
// ChannelMonitor: local commitment + local HTLC-timeout (2)
// Check the pair local commitment and HTLC-timeout broadcast due to HTLC expiration
+ assert_eq!(node_txn[2].input.len(), 1);
+ check_spends!(node_txn[2], chan_1.3);
assert_eq!(node_txn[3].input.len(), 1);
- check_spends!(node_txn[3], chan_1.3);
- assert_eq!(node_txn[0].input.len(), 1);
- let witness_script = node_txn[0].input[0].witness.last().unwrap();
+ let witness_script = node_txn[3].input[0].witness.last().unwrap();
assert_eq!(witness_script.len(), OFFERED_HTLC_SCRIPT_WEIGHT); //Spending an offered htlc output
- check_spends!(node_txn[0], node_txn[3]);
+ check_spends!(node_txn[3], node_txn[2]);
// Justice transactions are indices 1-2-4
+ assert_eq!(node_txn[0].input.len(), 1);
assert_eq!(node_txn[1].input.len(), 1);
- assert_eq!(node_txn[2].input.len(), 1);
assert_eq!(node_txn[4].input.len(), 1);
+ check_spends!(node_txn[0], revoked_local_txn[0]);
check_spends!(node_txn[1], revoked_local_txn[0]);
- check_spends!(node_txn[2], revoked_local_txn[0]);
check_spends!(node_txn[4], revoked_local_txn[0]);
let mut witness_lens = BTreeSet::new();
+ witness_lens.insert(node_txn[0].input[0].witness.last().unwrap().len());
witness_lens.insert(node_txn[1].input[0].witness.last().unwrap().len());
- witness_lens.insert(node_txn[2].input[0].witness.last().unwrap().len());
witness_lens.insert(node_txn[4].input[0].witness.last().unwrap().len());
assert_eq!(witness_lens.len(), 3);
assert_eq!(*witness_lens.iter().skip(0).next().unwrap(), 77); // revoked to_local
{
let mut node_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap();
assert_eq!(node_txn.len(), 5); // ChannelManager : 2 (commitment tx, HTLC-Timeout tx), ChannelMonitor : 2 (local commitment tx + HTLC-timeout), 1 timeout tx
+ assert_eq!(node_txn[1], node_txn[3]);
+ assert_eq!(node_txn[2], node_txn[4]);
- assert_eq!(node_txn[2], node_txn[3]);
- assert_eq!(node_txn[0], node_txn[4]);
-
- check_spends!(node_txn[1], commitment_tx[0]);
- assert_eq!(node_txn[1].clone().input[0].witness.last().unwrap().len(), ACCEPTED_HTLC_SCRIPT_WEIGHT);
+ check_spends!(node_txn[0], commitment_tx[0]);
+ assert_eq!(node_txn[0].clone().input[0].witness.last().unwrap().len(), ACCEPTED_HTLC_SCRIPT_WEIGHT);
- check_spends!(node_txn[2], chan_2.3);
- check_spends!(node_txn[0], node_txn[2]);
- assert_eq!(node_txn[2].clone().input[0].witness.last().unwrap().len(), 71);
- assert_eq!(node_txn[0].clone().input[0].witness.last().unwrap().len(), OFFERED_HTLC_SCRIPT_WEIGHT);
+ check_spends!(node_txn[1], chan_2.3);
+ check_spends!(node_txn[2], node_txn[1]);
+ assert_eq!(node_txn[1].clone().input[0].witness.last().unwrap().len(), 71);
+ assert_eq!(node_txn[2].clone().input[0].witness.last().unwrap().len(), OFFERED_HTLC_SCRIPT_WEIGHT);
- timeout_tx = node_txn[1].clone();
+ timeout_tx = node_txn[0].clone();
node_txn.clear();
}
check_added_monitors!(nodes[0], 1);
let revoked_htlc_txn = nodes[0].tx_broadcaster.txn_broadcasted.lock().unwrap();
- assert_eq!(revoked_htlc_txn.len(), 3);
- assert_eq!(revoked_htlc_txn[0], revoked_htlc_txn[2]);
+ assert_eq!(revoked_htlc_txn.len(), 2);
assert_eq!(revoked_htlc_txn[0].input.len(), 1);
assert_eq!(revoked_htlc_txn[0].input[0].witness.last().unwrap().len(), OFFERED_HTLC_SCRIPT_WEIGHT);
check_spends!(revoked_htlc_txn[0], revoked_local_txn[0]);
check_added_monitors!(nodes[1], 1);
let revoked_htlc_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap();
- assert_eq!(revoked_htlc_txn.len(), 3);
- assert_eq!(revoked_htlc_txn[0], revoked_htlc_txn[2]);
+ assert_eq!(revoked_htlc_txn.len(), 2);
assert_eq!(revoked_htlc_txn[0].input.len(), 1);
assert_eq!(revoked_htlc_txn[0].input[0].witness.last().unwrap().len(), ACCEPTED_HTLC_SCRIPT_WEIGHT);
check_spends!(revoked_htlc_txn[0], revoked_local_txn[0]);
check_added_monitors!(nodes[1], 1);
let revoked_htlc_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap();
- assert_eq!(revoked_htlc_txn.len(), 6);
+ assert_eq!(revoked_htlc_txn.len(), 4);
if revoked_htlc_txn[0].input[0].witness.last().unwrap().len() == ACCEPTED_HTLC_SCRIPT_WEIGHT {
assert_eq!(revoked_htlc_txn[0].input.len(), 1);
check_spends!(revoked_htlc_txn[0], revoked_local_txn[0]);
let partial_claim_tx = {
let node_txn = nodes[1].tx_broadcaster.txn_broadcasted.lock().unwrap();
assert_eq!(node_txn.len(), 3);
- check_spends!(node_txn[0], node_txn[2]);
- check_spends!(node_txn[1], node_txn[2]);
- assert_eq!(node_txn[0].input.len(), 1);
+ check_spends!(node_txn[1], node_txn[0]);
+ check_spends!(node_txn[2], node_txn[0]);
assert_eq!(node_txn[1].input.len(), 1);
- node_txn[0].clone()
+ assert_eq!(node_txn[2].input.len(), 1);
+ node_txn[1].clone()
};
// Broadcast partial claim on node A, should regenerate a claiming tx with HTLC dropped
use bitcoin_hashes::sha256d::Hash as Sha256dHash;
-use secp256k1::{Secp256k1, Signature};
+use secp256k1::Secp256k1;
use secp256k1;
use ln::msgs::DecodeError;
use ln::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER, InputMaterial, ClaimRequest};
-use ln::channelmanager::{HTLCSource, PaymentPreimage};
-use ln::chan_utils;
-use ln::chan_utils::{HTLCType, LocalCommitmentTransaction, TxCreationKeys, HTLCOutputInCommitment};
+use ln::channelmanager::PaymentPreimage;
+use ln::chan_utils::{HTLCType, LocalCommitmentTransaction};
use chain::chaininterface::{FeeEstimator, BroadcasterInterface, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
use chain::keysinterface::ChannelKeys;
use util::logger::Logger;
use util::ser::{ReadableArgs, Readable, Writer, Writeable};
use util::byte_utils;
-use std::collections::{HashMap, hash_map, HashSet};
+use std::collections::{HashMap, hash_map};
use std::sync::Arc;
use std::cmp;
use std::ops::Deref;
}
}
-/// Cache public keys and feerate used to compute any HTLC transaction.
-/// We only keep state for latest 2 commitment transactions as we should
-/// never have to generate HTLC txn for revoked local commitment
-struct HTLCTxCache {
- local_keys: TxCreationKeys,
- feerate_per_kw: u64,
- per_htlc: HashMap<u32, (HTLCOutputInCommitment, Option<Signature>)>
-}
-
/// Higher-level cache structure needed to re-generate bumped claim txn if needed
#[derive(Clone, PartialEq)]
pub struct ClaimTxBumpMaterial {
funding_redeemscript: Script,
local_commitment: Option<LocalCommitmentTransaction>,
prev_local_commitment: Option<LocalCommitmentTransaction>,
- current_htlc_cache: Option<HTLCTxCache>,
- prev_htlc_cache: Option<HTLCTxCache>,
local_csv: u16,
key_storage: ChanSigner,
self.local_commitment.write(writer)?;
self.prev_local_commitment.write(writer)?;
- macro_rules! serialize_htlc_cache {
- ($cache: expr) => {
- $cache.local_keys.write(writer)?;
- $cache.feerate_per_kw.write(writer)?;
- writer.write_all(&byte_utils::be64_to_array($cache.per_htlc.len() as u64))?;
- for (_, &(ref htlc, ref sig)) in $cache.per_htlc.iter() {
- htlc.write(writer)?;
- if let &Some(ref their_sig) = sig {
- 1u8.write(writer)?;
- writer.write_all(&their_sig.serialize_compact())?;
- } else {
- 0u8.write(writer)?;
- }
- }
- }
- }
-
- if let Some(ref current) = self.current_htlc_cache {
- writer.write_all(&[1; 1])?;
- serialize_htlc_cache!(current);
- } else {
- writer.write_all(&[0; 1])?;
- }
-
- if let Some(ref prev) = self.prev_htlc_cache {
- writer.write_all(&[1; 1])?;
- serialize_htlc_cache!(prev);
- } else {
- writer.write_all(&[0; 1])?;
- }
self.local_csv.write(writer)?;
self.key_storage.write(writer)?;
fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
let destination_script = Readable::read(reader)?;
let funding_redeemscript = Readable::read(reader)?;
+
let local_commitment = Readable::read(reader)?;
let prev_local_commitment = Readable::read(reader)?;
- macro_rules! read_htlc_cache {
- () => {
- {
- let local_keys = Readable::read(reader)?;
- let feerate_per_kw = Readable::read(reader)?;
- let htlcs_count: u64 = Readable::read(reader)?;
- let mut per_htlc = HashMap::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
- for _ in 0..htlcs_count {
- let htlc: HTLCOutputInCommitment = Readable::read(reader)?;
- let sigs = match <u8 as Readable>::read(reader)? {
- 0 => None,
- 1 => Some(Readable::read(reader)?),
- _ => return Err(DecodeError::InvalidValue),
- };
- per_htlc.insert(htlc.transaction_output_index.unwrap(), (htlc, sigs));
- }
- HTLCTxCache {
- local_keys,
- feerate_per_kw,
- per_htlc
- }
- }
- }
- }
-
- let current_htlc_cache = match <u8 as Readable>::read(reader)? {
- 0 => None,
- 1 => {
- Some(read_htlc_cache!())
- }
- _ => return Err(DecodeError::InvalidValue),
- };
-
- let prev_htlc_cache = match <u8 as Readable>::read(reader)? {
- 0 => None,
- 1 => {
- Some(read_htlc_cache!())
- }
- _ => return Err(DecodeError::InvalidValue),
- };
let local_csv = Readable::read(reader)?;
let key_storage = Readable::read(reader)?;
funding_redeemscript,
local_commitment,
prev_local_commitment,
- current_htlc_cache,
- prev_htlc_cache,
local_csv,
key_storage,
claimable_outpoints,
funding_redeemscript,
local_commitment: None,
prev_local_commitment: None,
- current_htlc_cache: None,
- prev_htlc_cache: None,
local_csv,
key_storage,
pending_claim_requests: HashMap::new(),
/// Lightning security model (i.e being able to redeem/timeout HTLC or penalize coutnerparty onchain) lays on the assumption of claim transactions getting confirmed before timelock expiration
/// (CSV or CLTV following cases). In case of high-fee spikes, claim tx may stuck in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or Child-Pay-For-Parent.
- fn generate_claim_tx<F: Deref>(&self, height: u32, cached_claim_datas: &ClaimTxBumpMaterial, fee_estimator: F) -> Option<(Option<u32>, u64, Transaction)>
+ fn generate_claim_tx<F: Deref>(&mut self, height: u32, cached_claim_datas: &ClaimTxBumpMaterial, fee_estimator: F) -> Option<(Option<u32>, u64, Transaction)>
where F::Target: FeeEstimator
{
if cached_claim_datas.per_input_material.len() == 0 { return None } // But don't prune pending claiming request yet, we may have to resurrect HTLCs
inputs_witnesses_weight += Self::get_witnesses_weight(if preimage.is_some() { &[InputDescriptors::OfferedHTLC] } else { &[InputDescriptors::ReceivedHTLC] });
amt += *amount;
},
- &InputMaterial::LocalHTLC { .. } => { return None; }
+ &InputMaterial::LocalHTLC { .. } => {
+ dynamic_fee = false;
+ },
&InputMaterial::Funding { .. } => {
dynamic_fee = false;
}
}
}
-
if dynamic_fee {
let predicted_weight = bumped_tx.get_weight() + inputs_witnesses_weight;
let mut new_feerate;
} else {
for (_, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() {
match per_outp_material {
- &InputMaterial::LocalHTLC { .. } => {
- //TODO : Given that Local Commitment Transaction and HTLC-Timeout/HTLC-Success are counter-signed by peer, we can't
- // RBF them. Need a Lightning specs change and package relay modification :
- // https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-November/016518.html
+ &InputMaterial::LocalHTLC { ref preimage, ref amount } => {
+ let mut htlc_tx = None;
+ if let Some(ref mut local_commitment) = self.local_commitment {
+ if local_commitment.txid() == outp.txid {
+ self.key_storage.sign_htlc_transaction(local_commitment, outp.vout, *preimage, self.local_csv, &self.secp_ctx);
+ htlc_tx = local_commitment.htlc_with_valid_witness(outp.vout).clone();
+ }
+ }
+ if let Some(ref mut prev_local_commitment) = self.prev_local_commitment {
+ if prev_local_commitment.txid() == outp.txid {
+ self.key_storage.sign_htlc_transaction(prev_local_commitment, outp.vout, *preimage, self.local_csv, &self.secp_ctx);
+ htlc_tx = prev_local_commitment.htlc_with_valid_witness(outp.vout).clone();
+ }
+ }
+ if let Some(htlc_tx) = htlc_tx {
+ let feerate = (amount - htlc_tx.output[0].value) * 1000 / htlc_tx.get_weight() as u64;
+ // Timer set to $NEVER given we can't bump tx without anchor outputs
+ log_trace!(self, "Going to broadcast Local HTLC-{} claiming HTLC output {} from {}...", if preimage.is_some() { "Success" } else { "Timeout" }, outp.vout, outp.txid);
+ return Some((None, feerate, htlc_tx));
+ }
return None;
},
&InputMaterial::Funding { ref channel_value } => {
- if self.local_commitment.is_some() {
- let mut local_commitment = self.local_commitment.clone().unwrap();
- self.key_storage.sign_local_commitment(&mut local_commitment, &self.funding_redeemscript, *channel_value, &self.secp_ctx);
+ if let Some(ref mut local_commitment) = self.local_commitment {
+ self.key_storage.sign_local_commitment(local_commitment, &self.funding_redeemscript, *channel_value, &self.secp_ctx);
let signed_tx = local_commitment.with_valid_witness().clone();
let mut amt_outputs = 0;
for outp in signed_tx.output.iter() {
}
}
- let mut bump_candidates = HashSet::new();
+ let mut bump_candidates = HashMap::new();
for tx in txn_matched {
// Scan all input to verify is one of the outpoint spent is of interest for us
let mut claimed_outputs_material = Vec::new();
}
//TODO: recompute soonest_timelock to avoid wasting a bit on fees
if at_least_one_drop {
- bump_candidates.insert(first_claim_txid_height.0.clone());
+ bump_candidates.insert(first_claim_txid_height.0.clone(), claim_material.clone());
}
}
break; //No need to iterate further, either tx is our or their
for (first_claim_txid, ref claim_data) in self.pending_claim_requests.iter() {
if let Some(h) = claim_data.height_timer {
if h == height {
- bump_candidates.insert(*first_claim_txid);
+ bump_candidates.insert(*first_claim_txid, (*claim_data).clone());
}
}
}
// Build, bump and rebroadcast tx accordingly
log_trace!(self, "Bumping {} candidates", bump_candidates.len());
- for first_claim_txid in bump_candidates.iter() {
- if let Some((new_timer, new_feerate)) = {
- if let Some(claim_material) = self.pending_claim_requests.get(first_claim_txid) {
- if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator) {
- log_trace!(self, "Broadcast onchain {}", log_tx!(bump_tx));
- broadcaster.broadcast_transaction(&bump_tx);
- Some((new_timer, new_feerate))
- } else { None }
- } else { unreachable!(); }
- } {
- if let Some(claim_material) = self.pending_claim_requests.get_mut(first_claim_txid) {
- claim_material.height_timer = new_timer;
- claim_material.feerate_previous = new_feerate;
- } else { unreachable!(); }
+ let mut pending_claim_updates = Vec::with_capacity(bump_candidates.len());
+ for (first_claim_txid, claim_material) in bump_candidates.iter() {
+ if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &claim_material, &*fee_estimator) {
+ log_trace!(self, "Broadcast onchain {}", log_tx!(bump_tx));
+ broadcaster.broadcast_transaction(&bump_tx);
+ pending_claim_updates.push((*first_claim_txid, new_timer, new_feerate));
+ }
+ }
+ for updates in pending_claim_updates {
+ if let Some(claim_material) = self.pending_claim_requests.get_mut(&updates.0) {
+ claim_material.height_timer = updates.1;
+ claim_material.feerate_previous = updates.2;
}
}
}
}
}
- pub(super) fn provide_latest_local_tx(&mut self, tx: LocalCommitmentTransaction, local_keys: chan_utils::TxCreationKeys, feerate_per_kw: u64, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), ()> {
+ pub(super) fn provide_latest_local_tx(&mut self, tx: LocalCommitmentTransaction) -> Result<(), ()> {
// To prevent any unsafe state discrepancy between offchain and onchain, once local
// commitment transaction has been signed due to an event (either block height for
// HTLC-timeout or channel force-closure), don't allow any further update of local
}
self.prev_local_commitment = self.local_commitment.take();
self.local_commitment = Some(tx);
- self.prev_htlc_cache = self.current_htlc_cache.take();
- let mut per_htlc = HashMap::with_capacity(htlc_outputs.len());
- for htlc in htlc_outputs {
- if htlc.0.transaction_output_index.is_some() { // Discard dust HTLC as we will never have to generate onchain tx for them
- per_htlc.insert(htlc.0.transaction_output_index.unwrap(), (htlc.0, htlc.1));
- }
- }
- self.current_htlc_cache = Some(HTLCTxCache {
- local_keys,
- feerate_per_kw,
- per_htlc
- });
Ok(())
}
pub(super) fn get_fully_signed_htlc_tx(&mut self, txid: Sha256dHash, htlc_index: u32, preimage: Option<PaymentPreimage>) -> Option<Transaction> {
//TODO: store preimage in OnchainTxHandler
- if let Some(ref local_commitment) = self.local_commitment {
+ if let Some(ref mut local_commitment) = self.local_commitment {
if local_commitment.txid() == txid {
- if let Some(ref htlc_cache) = self.current_htlc_cache {
- if let Some(htlc) = htlc_cache.per_htlc.get(&htlc_index) {
- if !htlc.0.offered && preimage.is_none() { return None; }; // If we don't have preimage for HTLC-Success, don't try to generate
- let htlc_secret = if !htlc.0.offered { preimage } else { None }; // If we have a preimage for a HTLC-Timeout, don't use it that's likely a duplicate HTLC hash
- let mut htlc_tx = chan_utils::build_htlc_transaction(&txid, htlc_cache.feerate_per_kw, self.local_csv, &htlc.0, &htlc_cache.local_keys.a_delayed_payment_key, &htlc_cache.local_keys.revocation_key);
- self.key_storage.sign_htlc_transaction(&mut htlc_tx, htlc.1.as_ref().unwrap(), &htlc_secret, &htlc.0, &htlc_cache.local_keys.a_htlc_key, &htlc_cache.local_keys.b_htlc_key, &htlc_cache.local_keys.revocation_key, &htlc_cache.local_keys.per_commitment_point, &self.secp_ctx);
- return Some(htlc_tx);
-
- }
- }
+ self.key_storage.sign_htlc_transaction(local_commitment, htlc_index, preimage, self.local_csv, &self.secp_ctx);
+ return local_commitment.htlc_with_valid_witness(htlc_index).clone();
}
}
None
self.inner.unsafe_sign_local_commitment(local_commitment_tx, funding_redeemscript, channel_value_satoshis, secp_ctx);
}
- fn sign_htlc_transaction<T: secp256k1::Signing>(&self, htlc_tx: &mut Transaction, their_sig: &Signature, preimage: &Option<PaymentPreimage>, htlc: &HTLCOutputInCommitment, a_htlc_key: &PublicKey, b_htlc_key: &PublicKey, revocation_key: &PublicKey, per_commitment_point: &PublicKey, secp_ctx: &Secp256k1<T>) {
- self.inner.sign_htlc_transaction(htlc_tx, their_sig, preimage, htlc, a_htlc_key, b_htlc_key, revocation_key, per_commitment_point, secp_ctx);
+ fn sign_htlc_transaction<T: secp256k1::Signing>(&self, local_commitment_tx: &mut LocalCommitmentTransaction, htlc_index: u32, preimage: Option<PaymentPreimage>, local_csv: u16, secp_ctx: &Secp256k1<T>) {
+ self.inner.sign_htlc_transaction(local_commitment_tx, htlc_index, preimage, local_csv, secp_ctx);
}
fn sign_closing_transaction<T: secp256k1::Signing>(&self, closing_tx: &Transaction, secp_ctx: &Secp256k1<T>) -> Result<Signature, ()> {