use secp256k1;
use ln::msgs::DecodeError;
-use ln::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER, InputMaterial};
+use ln::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER, InputMaterial, ClaimRequest};
use ln::chan_utils::HTLCType;
use chain::chaininterface::{FeeEstimator, BroadcasterInterface, ConfirmationTarget, MIN_RELAY_FEE_SAT_PER_1000_WEIGHT};
-use chain::keysinterface::SpendableOutputDescriptor;
+use chain::keysinterface::ChannelKeys;
use util::logger::Logger;
use util::ser::{ReadableArgs, Readable, Writer, Writeable};
use util::byte_utils;
/// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
/// do RBF bumping if possible.
-#[derive(Clone)]
-pub struct OnchainTxHandler {
+pub struct OnchainTxHandler<ChanSigner: ChannelKeys> {
destination_script: Script,
+ key_storage: ChanSigner,
+
// Used to track claiming requests. If claim tx doesn't confirm before height timer expiration we need to bump
// it (RBF or CPFP). If an input has been part of an aggregate tx at first claim try, we need to keep it within
// another bumped aggregate tx to comply with RBF rules. We may have multiple claiming txn in the flight for the
logger: Arc<Logger>
}
-impl Writeable for OnchainTxHandler {
- fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
+impl<ChanSigner: ChannelKeys + Writeable> OnchainTxHandler<ChanSigner> {
+ pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
self.destination_script.write(writer)?;
+ self.key_storage.write(writer)?;
+
writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
for (ref ancestor_claim_txid, claim_tx_data) in self.pending_claim_requests.iter() {
ancestor_claim_txid.write(writer)?;
}
}
-impl ReadableArgs<Arc<Logger>> for OnchainTxHandler {
+impl<ChanSigner: ChannelKeys + Readable> ReadableArgs<Arc<Logger>> for OnchainTxHandler<ChanSigner> {
fn read<R: ::std::io::Read>(reader: &mut R, logger: Arc<Logger>) -> Result<Self, DecodeError> {
let destination_script = Readable::read(reader)?;
+ let key_storage = Readable::read(reader)?;
+
let pending_claim_requests_len: u64 = Readable::read(reader)?;
let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
for _ in 0..pending_claim_requests_len {
Ok(OnchainTxHandler {
destination_script,
+ key_storage,
claimable_outpoints,
pending_claim_requests,
onchain_events_waiting_threshold_conf,
}
}
-impl OnchainTxHandler {
- pub(super) fn new(destination_script: Script, logger: Arc<Logger>) -> Self {
+impl<ChanSigner: ChannelKeys> OnchainTxHandler<ChanSigner> {
+ pub(super) fn new(destination_script: Script, keys: ChanSigner, logger: Arc<Logger>) -> Self {
+
+ let key_storage = keys;
+
OnchainTxHandler {
destination_script,
+ key_storage,
pending_claim_requests: HashMap::new(),
claimable_outpoints: HashMap::new(),
onchain_events_waiting_threshold_conf: HashMap::new(),
tx_weight
}
+ /// In LN, output claimed are time-sensitive, which means we have to spend them before reaching some timelock expiration. At in-channel
+ /// output detection, we generate a first version of a claim tx and associate to it a height timer. A height timer is an absolute block
+ /// height than once reached we should generate a new bumped "version" of the claim tx to be sure than we safely claim outputs before
+ /// than our counterparty can do it too. If timelock expires soon, height timer is going to be scale down in consequence to increase
+ /// frequency of the bump and so increase our bets of success.
fn get_height_timer(current_height: u32, timelock_expiration: u32) -> u32 {
if timelock_expiration <= current_height + 3 {
return current_height + 1
}
}
+ // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
+ // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
let new_timer = Self::get_height_timer(height, cached_claim_datas.soonest_timelock);
let mut inputs_witnesses_weight = 0;
let mut amt = 0;
for per_outp_material in cached_claim_datas.per_input_material.values() {
match per_outp_material {
- &InputMaterial::Revoked { ref script, ref is_htlc, ref amount, .. } => {
- inputs_witnesses_weight += Self::get_witnesses_weight(if !is_htlc { &[InputDescriptors::RevokedOutput] } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::OfferedHTLC) { &[InputDescriptors::RevokedOfferedHTLC] } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::AcceptedHTLC) { &[InputDescriptors::RevokedReceivedHTLC] } else { unreachable!() });
+ &InputMaterial::Revoked { ref witness_script, ref is_htlc, ref amount, .. } => {
+ inputs_witnesses_weight += Self::get_witnesses_weight(if !is_htlc { &[InputDescriptors::RevokedOutput] } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { &[InputDescriptors::RevokedOfferedHTLC] } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { &[InputDescriptors::RevokedReceivedHTLC] } else { unreachable!() });
amt += *amount;
},
&InputMaterial::RemoteHTLC { ref preimage, ref amount, .. } => {
for (i, (outp, per_outp_material)) in cached_claim_datas.per_input_material.iter().enumerate() {
match per_outp_material {
- &InputMaterial::Revoked { ref script, ref pubkey, ref key, ref is_htlc, ref amount } => {
+ &InputMaterial::Revoked { ref witness_script, ref pubkey, ref key, ref is_htlc, ref amount } => {
let sighash_parts = bip143::SighashComponents::new(&bumped_tx);
- let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &script, *amount)[..]);
+ let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]);
let sig = self.secp_ctx.sign(&sighash, &key);
bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
} else {
bumped_tx.input[i].witness.push(vec!(1));
}
- bumped_tx.input[i].witness.push(script.clone().into_bytes());
- log_trace!(self, "Going to broadcast Penalty Transaction {} claiming revoked {} output {} from {} with new feerate {}...", bumped_tx.txid(), if !is_htlc { "to_local" } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::OfferedHTLC) { "offered" } else if HTLCType::scriptlen_to_htlctype(script.len()) == Some(HTLCType::AcceptedHTLC) { "received" } else { "" }, outp.vout, outp.txid, new_feerate);
+ bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
+ log_trace!(self, "Going to broadcast Penalty Transaction {} claiming revoked {} output {} from {} with new feerate {}...", bumped_tx.txid(), if !is_htlc { "to_local" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::OfferedHTLC) { "offered" } else if HTLCType::scriptlen_to_htlctype(witness_script.len()) == Some(HTLCType::AcceptedHTLC) { "received" } else { "" }, outp.vout, outp.txid, new_feerate);
},
- &InputMaterial::RemoteHTLC { ref script, ref key, ref preimage, ref amount, ref locktime } => {
+ &InputMaterial::RemoteHTLC { ref witness_script, ref key, ref preimage, ref amount, ref locktime } => {
if !preimage.is_some() { bumped_tx.lock_time = *locktime }; // Right now we don't aggregate time-locked transaction, if we do we should set lock_time before to avoid breaking hash computation
let sighash_parts = bip143::SighashComponents::new(&bumped_tx);
- let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &script, *amount)[..]);
+ let sighash = hash_to_message!(&sighash_parts.sighash_all(&bumped_tx.input[i], &witness_script, *amount)[..]);
let sig = self.secp_ctx.sign(&sighash, &key);
bumped_tx.input[i].witness.push(sig.serialize_der().to_vec());
bumped_tx.input[i].witness[0].push(SigHashType::All as u8);
if let &Some(preimage) = preimage {
bumped_tx.input[i].witness.push(preimage.clone().0.to_vec());
} else {
- bumped_tx.input[i].witness.push(vec![0]);
+ bumped_tx.input[i].witness.push(vec![]);
}
- bumped_tx.input[i].witness.push(script.clone().into_bytes());
+ bumped_tx.input[i].witness.push(witness_script.clone().into_bytes());
log_trace!(self, "Going to broadcast Claim Transaction {} claiming remote {} htlc output {} from {} with new feerate {}...", bumped_tx.txid(), if preimage.is_some() { "offered" } else { "received" }, outp.vout, outp.txid, new_feerate);
},
&InputMaterial::LocalHTLC { .. } => {
Some((new_timer, new_feerate, bumped_tx))
}
- pub(super) fn block_connected<B: Deref, F: Deref>(&mut self, txn_matched: &[&Transaction], claimable_outpoints: Vec<Vec<(u32, bool, BitcoinOutPoint, InputMaterial)>>, height: u32, broadcaster: B, fee_estimator: F) -> Vec<SpendableOutputDescriptor>
+ pub(super) fn block_connected<B: Deref, F: Deref>(&mut self, txn_matched: &[&Transaction], claimable_outpoints: Vec<ClaimRequest>, height: u32, broadcaster: B, fee_estimator: F)
where B::Target: BroadcasterInterface,
F::Target: FeeEstimator
{
+ log_trace!(self, "Block at height {} connected with {} claim requests", height, claimable_outpoints.len());
let mut new_claims = Vec::new();
let mut aggregated_claim = HashMap::new();
let mut aggregated_soonest = ::std::u32::MAX;
- let mut spendable_outputs = Vec::new();
-
- // Try to aggregate outputs if they're 1) belong to same parent tx, 2) their
- // timelock expiration isn't imminent (<= CLTV_SHARED_CLAIM_BUFFER).
- for siblings_outpoints in claimable_outpoints {
- for outp in siblings_outpoints {
- // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
- if let Some(_) = self.claimable_outpoints.get(&outp.2) { log_trace!(self, "Bouncing off outpoint {}:{}, already registered its claiming request", outp.2.txid, outp.2.vout); } else {
- log_trace!(self, "Test if outpoint can be aggregated with expiration {} against {}", outp.0, height + CLTV_SHARED_CLAIM_BUFFER);
- if outp.0 <= height + CLTV_SHARED_CLAIM_BUFFER || !outp.1 { // Don't aggregate if outpoint absolute timelock is soon or marked as non-aggregable
- let mut single_input = HashMap::new();
- single_input.insert(outp.2, outp.3);
- new_claims.push((outp.0, single_input));
- } else {
- aggregated_claim.insert(outp.2, outp.3);
- if outp.0 < aggregated_soonest {
- aggregated_soonest = outp.0;
- }
+
+ // Try to aggregate outputs if their timelock expiration isn't imminent (absolute_timelock
+ // <= CLTV_SHARED_CLAIM_BUFFER) and they don't require an immediate nLockTime (aggregable).
+ for req in claimable_outpoints {
+ // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
+ if let Some(_) = self.claimable_outpoints.get(&req.outpoint) { log_trace!(self, "Bouncing off outpoint {}:{}, already registered its claiming request", req.outpoint.txid, req.outpoint.vout); } else {
+ log_trace!(self, "Test if outpoint can be aggregated with expiration {} against {}", req.absolute_timelock, height + CLTV_SHARED_CLAIM_BUFFER);
+ if req.absolute_timelock <= height + CLTV_SHARED_CLAIM_BUFFER || !req.aggregable { // Don't aggregate if outpoint absolute timelock is soon or marked as non-aggregable
+ let mut single_input = HashMap::new();
+ single_input.insert(req.outpoint, req.witness_data);
+ new_claims.push((req.absolute_timelock, single_input));
+ } else {
+ aggregated_claim.insert(req.outpoint, req.witness_data);
+ if req.absolute_timelock < aggregated_soonest {
+ aggregated_soonest = req.absolute_timelock;
}
}
}
self.claimable_outpoints.insert(k.clone(), (txid, height));
}
log_trace!(self, "Broadcast onchain {}", log_tx!(tx));
- spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
- outpoint: BitcoinOutPoint { txid: tx.txid(), vout: 0 },
- output: tx.output[0].clone(),
- });
broadcaster.broadcast_transaction(&tx);
}
}
if set_equality {
clean_claim_request_after_safety_delay!();
} else { // If false, generate new claim request with update outpoint set
+ let mut at_least_one_drop = false;
for input in tx.input.iter() {
if let Some(input_material) = claim_material.per_input_material.remove(&input.previous_output) {
claimed_outputs_material.push((input.previous_output, input_material));
+ at_least_one_drop = true;
}
// If there are no outpoints left to claim in this request, drop it entirely after ANTI_REORG_DELAY.
if claim_material.per_input_material.is_empty() {
}
}
//TODO: recompute soonest_timelock to avoid wasting a bit on fees
- bump_candidates.insert(first_claim_txid_height.0.clone());
+ if at_least_one_drop {
+ bump_candidates.insert(first_claim_txid_height.0.clone());
+ }
}
break; //No need to iterate further, either tx is our or their
} else {
}
// 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) {
} else { unreachable!(); }
}
}
-
- spendable_outputs
}
pub(super) fn block_disconnected<B: Deref, F: Deref>(&mut self, height: u32, broadcaster: B, fee_estimator: F)
projects / rust-lightning / blobdiff