1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to build claims and bump in-flight transactions until confirmations.
12 //! OnchainTxHandler objects are fully-part of ChannelMonitor and encapsulates all
13 //! building, tracking, bumping and notifications functions.
15 use bitcoin::blockdata::transaction::Transaction;
16 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
17 use bitcoin::blockdata::script::Script;
19 use bitcoin::hash_types::Txid;
21 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
22 use bitcoin::secp256k1;
24 use ln::msgs::DecodeError;
25 use ln::PaymentPreimage;
26 use ln::chan_utils::{ChannelTransactionParameters, HolderCommitmentTransaction};
27 use chain::chaininterface::{FeeEstimator, BroadcasterInterface, LowerBoundedFeeEstimator};
28 use chain::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER};
29 use chain::keysinterface::{Sign, KeysInterface};
30 use chain::package::PackageTemplate;
31 use util::logger::Logger;
32 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, VecWriter};
37 use alloc::collections::BTreeMap;
40 use core::mem::replace;
41 use bitcoin::hashes::Hash;
43 const MAX_ALLOC_SIZE: usize = 64*1024;
45 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
46 /// transaction causing it.
48 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
50 struct OnchainEventEntry {
56 impl OnchainEventEntry {
57 fn confirmation_threshold(&self) -> u32 {
58 self.height + ANTI_REORG_DELAY - 1
61 fn has_reached_confirmation_threshold(&self, height: u32) -> bool {
62 height >= self.confirmation_threshold()
66 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
67 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
70 /// Outpoint under claim process by our own tx, once this one get enough confirmations, we remove it from
71 /// bump-txn candidate buffer.
75 /// Claim tx aggregate multiple claimable outpoints. One of the outpoint may be claimed by a counterparty party tx.
76 /// In this case, we need to drop the outpoint and regenerate a new claim tx. By safety, we keep tracking
77 /// the outpoint to be sure to resurect it back to the claim tx if reorgs happen.
79 package: PackageTemplate,
83 impl Writeable for OnchainEventEntry {
84 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
85 write_tlv_fields!(writer, {
86 (0, self.txid, required),
87 (2, self.height, required),
88 (4, self.event, required),
94 impl MaybeReadable for OnchainEventEntry {
95 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
96 let mut txid = Txid::all_zeros();
99 read_tlv_fields!(reader, {
101 (2, height, required),
102 (4, event, ignorable),
104 if let Some(ev) = event {
105 Ok(Some(Self { txid, height, event: ev }))
112 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
114 (0, claim_request, required),
116 (1, ContentiousOutpoint) => {
117 (0, package, required),
121 impl Readable for Option<Vec<Option<(usize, Signature)>>> {
122 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
123 match Readable::read(reader)? {
126 let vlen: u64 = Readable::read(reader)?;
127 let mut ret = Vec::with_capacity(cmp::min(vlen as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<Option<(usize, Signature)>>()));
129 ret.push(match Readable::read(reader)? {
131 1u8 => Some((<u64 as Readable>::read(reader)? as usize, Readable::read(reader)?)),
132 _ => return Err(DecodeError::InvalidValue)
137 _ => Err(DecodeError::InvalidValue),
142 impl Writeable for Option<Vec<Option<(usize, Signature)>>> {
143 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
147 (vec.len() as u64).write(writer)?;
148 for opt in vec.iter() {
150 &Some((ref idx, ref sig)) => {
152 (*idx as u64).write(writer)?;
155 &None => 0u8.write(writer)?,
159 &None => 0u8.write(writer)?,
166 /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
167 /// do RBF bumping if possible.
168 pub struct OnchainTxHandler<ChannelSigner: Sign> {
169 destination_script: Script,
170 holder_commitment: HolderCommitmentTransaction,
171 // holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
172 // transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
173 // the set of HTLCs in the HolderCommitmentTransaction.
174 holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
175 prev_holder_commitment: Option<HolderCommitmentTransaction>,
176 prev_holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
178 pub(super) signer: ChannelSigner,
179 pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
181 // Used to track claiming requests. If claim tx doesn't confirm before height timer expiration we need to bump
182 // it (RBF or CPFP). If an input has been part of an aggregate tx at first claim try, we need to keep it within
183 // another bumped aggregate tx to comply with RBF rules. We may have multiple claiming txn in the flight for the
184 // same set of outpoints. One of the outpoints may be spent by a transaction not issued by us. That's why at
185 // block connection we scan all inputs and if any of them is among a set of a claiming request we test for set
186 // equality between spending transaction and claim request. If true, it means transaction was one our claiming one
187 // after a security delay of 6 blocks we remove pending claim request. If false, it means transaction wasn't and
188 // we need to regenerate new claim request with reduced set of still-claimable outpoints.
189 // Key is identifier of the pending claim request, i.e the txid of the initial claiming transaction generated by
190 // us and is immutable until all outpoint of the claimable set are post-anti-reorg-delay solved.
191 // Entry is cache of elements need to generate a bumped claiming transaction (see ClaimTxBumpMaterial)
192 #[cfg(test)] // Used in functional_test to verify sanitization
193 pub(crate) pending_claim_requests: HashMap<Txid, PackageTemplate>,
195 pending_claim_requests: HashMap<Txid, PackageTemplate>,
197 // Used to link outpoints claimed in a connected block to a pending claim request.
198 // Key is outpoint than monitor parsing has detected we have keys/scripts to claim
199 // Value is (pending claim request identifier, confirmation_block), identifier
200 // is txid of the initial claiming transaction and is immutable until outpoint is
201 // post-anti-reorg-delay solved, confirmaiton_block is used to erase entry if
202 // block with output gets disconnected.
203 #[cfg(test)] // Used in functional_test to verify sanitization
204 pub claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
206 claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
208 locktimed_packages: BTreeMap<u32, Vec<PackageTemplate>>,
210 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
212 pub(super) secp_ctx: Secp256k1<secp256k1::All>,
215 const SERIALIZATION_VERSION: u8 = 1;
216 const MIN_SERIALIZATION_VERSION: u8 = 1;
218 impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
219 pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
220 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
222 self.destination_script.write(writer)?;
223 self.holder_commitment.write(writer)?;
224 self.holder_htlc_sigs.write(writer)?;
225 self.prev_holder_commitment.write(writer)?;
226 self.prev_holder_htlc_sigs.write(writer)?;
228 self.channel_transaction_parameters.write(writer)?;
230 let mut key_data = VecWriter(Vec::new());
231 self.signer.write(&mut key_data)?;
232 assert!(key_data.0.len() < core::usize::MAX);
233 assert!(key_data.0.len() < core::u32::MAX as usize);
234 (key_data.0.len() as u32).write(writer)?;
235 writer.write_all(&key_data.0[..])?;
237 writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
238 for (ref ancestor_claim_txid, request) in self.pending_claim_requests.iter() {
239 ancestor_claim_txid.write(writer)?;
240 request.write(writer)?;
243 writer.write_all(&byte_utils::be64_to_array(self.claimable_outpoints.len() as u64))?;
244 for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
246 claim_and_height.0.write(writer)?;
247 claim_and_height.1.write(writer)?;
250 writer.write_all(&byte_utils::be64_to_array(self.locktimed_packages.len() as u64))?;
251 for (ref locktime, ref packages) in self.locktimed_packages.iter() {
252 locktime.write(writer)?;
253 writer.write_all(&byte_utils::be64_to_array(packages.len() as u64))?;
254 for ref package in packages.iter() {
255 package.write(writer)?;
259 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
260 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
261 entry.write(writer)?;
264 write_tlv_fields!(writer, {});
269 impl<'a, K: KeysInterface> ReadableArgs<&'a K> for OnchainTxHandler<K::Signer> {
270 fn read<R: io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
271 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
273 let destination_script = Readable::read(reader)?;
275 let holder_commitment = Readable::read(reader)?;
276 let holder_htlc_sigs = Readable::read(reader)?;
277 let prev_holder_commitment = Readable::read(reader)?;
278 let prev_holder_htlc_sigs = Readable::read(reader)?;
280 let channel_parameters = Readable::read(reader)?;
282 let keys_len: u32 = Readable::read(reader)?;
283 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
284 while keys_data.len() != keys_len as usize {
285 // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
286 let mut data = [0; 1024];
287 let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
288 reader.read_exact(read_slice)?;
289 keys_data.extend_from_slice(read_slice);
291 let signer = keys_manager.read_chan_signer(&keys_data)?;
293 let pending_claim_requests_len: u64 = Readable::read(reader)?;
294 let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
295 for _ in 0..pending_claim_requests_len {
296 pending_claim_requests.insert(Readable::read(reader)?, Readable::read(reader)?);
299 let claimable_outpoints_len: u64 = Readable::read(reader)?;
300 let mut claimable_outpoints = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
301 for _ in 0..claimable_outpoints_len {
302 let outpoint = Readable::read(reader)?;
303 let ancestor_claim_txid = Readable::read(reader)?;
304 let height = Readable::read(reader)?;
305 claimable_outpoints.insert(outpoint, (ancestor_claim_txid, height));
308 let locktimed_packages_len: u64 = Readable::read(reader)?;
309 let mut locktimed_packages = BTreeMap::new();
310 for _ in 0..locktimed_packages_len {
311 let locktime = Readable::read(reader)?;
312 let packages_len: u64 = Readable::read(reader)?;
313 let mut packages = Vec::with_capacity(cmp::min(packages_len as usize, MAX_ALLOC_SIZE / core::mem::size_of::<PackageTemplate>()));
314 for _ in 0..packages_len {
315 packages.push(Readable::read(reader)?);
317 locktimed_packages.insert(locktime, packages);
320 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
321 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
322 for _ in 0..waiting_threshold_conf_len {
323 if let Some(val) = MaybeReadable::read(reader)? {
324 onchain_events_awaiting_threshold_conf.push(val);
328 read_tlv_fields!(reader, {});
330 let mut secp_ctx = Secp256k1::new();
331 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
333 Ok(OnchainTxHandler {
337 prev_holder_commitment,
338 prev_holder_htlc_sigs,
340 channel_transaction_parameters: channel_parameters,
343 pending_claim_requests,
344 onchain_events_awaiting_threshold_conf,
350 impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
351 pub(crate) fn new(destination_script: Script, signer: ChannelSigner, channel_parameters: ChannelTransactionParameters, holder_commitment: HolderCommitmentTransaction, secp_ctx: Secp256k1<secp256k1::All>) -> Self {
355 holder_htlc_sigs: None,
356 prev_holder_commitment: None,
357 prev_holder_htlc_sigs: None,
359 channel_transaction_parameters: channel_parameters,
360 pending_claim_requests: HashMap::new(),
361 claimable_outpoints: HashMap::new(),
362 locktimed_packages: BTreeMap::new(),
363 onchain_events_awaiting_threshold_conf: Vec::new(),
369 pub(crate) fn get_prev_holder_commitment_to_self_value(&self) -> Option<u64> {
370 self.prev_holder_commitment.as_ref().map(|commitment| commitment.to_broadcaster_value_sat())
373 pub(crate) fn get_cur_holder_commitment_to_self_value(&self) -> u64 {
374 self.holder_commitment.to_broadcaster_value_sat()
377 /// 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
378 /// (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.
379 /// Panics if there are signing errors, because signing operations in reaction to on-chain events
380 /// are not expected to fail, and if they do, we may lose funds.
381 fn generate_claim_tx<F: Deref, L: Deref>(&mut self, cur_height: u32, cached_request: &PackageTemplate, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L) -> Option<(Option<u32>, u64, Transaction)>
382 where F::Target: FeeEstimator,
385 if cached_request.outpoints().len() == 0 { return None } // But don't prune pending claiming request yet, we may have to resurrect HTLCs
387 // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
388 // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
389 let new_timer = Some(cached_request.get_height_timer(cur_height));
390 if cached_request.is_malleable() {
391 let predicted_weight = cached_request.package_weight(&self.destination_script, self.channel_transaction_parameters.opt_anchors.is_some());
392 if let Some((output_value, new_feerate)) =
393 cached_request.compute_package_output(predicted_weight, self.destination_script.dust_value().to_sat(), fee_estimator, logger) {
394 assert!(new_feerate != 0);
396 let transaction = cached_request.finalize_package(self, output_value, self.destination_script.clone(), logger).unwrap();
397 log_trace!(logger, "...with timer {} and feerate {}", new_timer.unwrap(), new_feerate);
398 assert!(predicted_weight >= transaction.weight());
399 return Some((new_timer, new_feerate, transaction))
402 // Note: Currently, amounts of holder outputs spending witnesses aren't used
403 // as we can't malleate spending package to increase their feerate. This
404 // should change with the remaining anchor output patchset.
405 if let Some(transaction) = cached_request.finalize_package(self, 0, self.destination_script.clone(), logger) {
406 return Some((None, 0, transaction));
412 /// Upon channelmonitor.block_connected(..) or upon provision of a preimage on the forward link
413 /// for this channel, provide new relevant on-chain transactions and/or new claim requests.
414 /// Formerly this was named `block_connected`, but it is now also used for claiming an HTLC output
415 /// if we receive a preimage after force-close.
416 /// `conf_height` represents the height at which the transactions in `txn_matched` were
417 /// confirmed. This does not need to equal the current blockchain tip height, which should be
418 /// provided via `cur_height`, however it must never be higher than `cur_height`.
419 pub(crate) fn update_claims_view<B: Deref, F: Deref, L: Deref>(&mut self, txn_matched: &[&Transaction], requests: Vec<PackageTemplate>, conf_height: u32, cur_height: u32, broadcaster: &B, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
420 where B::Target: BroadcasterInterface,
421 F::Target: FeeEstimator,
424 log_debug!(logger, "Updating claims view at height {} with {} matched transactions in block {} and {} claim requests", cur_height, txn_matched.len(), conf_height, requests.len());
425 let mut preprocessed_requests = Vec::with_capacity(requests.len());
426 let mut aggregated_request = None;
428 // Try to aggregate outputs if their timelock expiration isn't imminent (package timelock
429 // <= CLTV_SHARED_CLAIM_BUFFER) and they don't require an immediate nLockTime (aggregable).
430 for req in requests {
431 // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
432 if let Some(_) = self.claimable_outpoints.get(req.outpoints()[0]) {
433 log_info!(logger, "Ignoring second claim for outpoint {}:{}, already registered its claiming request", req.outpoints()[0].txid, req.outpoints()[0].vout);
435 let timelocked_equivalent_package = self.locktimed_packages.iter().map(|v| v.1.iter()).flatten()
436 .find(|locked_package| locked_package.outpoints() == req.outpoints());
437 if let Some(package) = timelocked_equivalent_package {
438 log_info!(logger, "Ignoring second claim for outpoint {}:{}, we already have one which we're waiting on a timelock at {} for.",
439 req.outpoints()[0].txid, req.outpoints()[0].vout, package.package_timelock());
443 if req.package_timelock() > cur_height + 1 {
444 log_info!(logger, "Delaying claim of package until its timelock at {} (current height {}), the following outpoints are spent:", req.package_timelock(), cur_height);
445 for outpoint in req.outpoints() {
446 log_info!(logger, " Outpoint {}", outpoint);
448 self.locktimed_packages.entry(req.package_timelock()).or_insert(Vec::new()).push(req);
452 log_trace!(logger, "Test if outpoint can be aggregated with expiration {} against {}", req.timelock(), cur_height + CLTV_SHARED_CLAIM_BUFFER);
453 if req.timelock() <= cur_height + CLTV_SHARED_CLAIM_BUFFER || !req.aggregable() {
454 // Don't aggregate if outpoint package timelock is soon or marked as non-aggregable
455 preprocessed_requests.push(req);
456 } else if aggregated_request.is_none() {
457 aggregated_request = Some(req);
459 aggregated_request.as_mut().unwrap().merge_package(req);
463 if let Some(req) = aggregated_request {
464 preprocessed_requests.push(req);
467 // Claim everything up to and including cur_height + 1
468 let remaining_locked_packages = self.locktimed_packages.split_off(&(cur_height + 2));
469 for (pop_height, mut entry) in self.locktimed_packages.iter_mut() {
470 log_trace!(logger, "Restoring delayed claim of package(s) at their timelock at {}.", pop_height);
471 preprocessed_requests.append(&mut entry);
473 self.locktimed_packages = remaining_locked_packages;
475 // Generate claim transactions and track them to bump if necessary at
476 // height timer expiration (i.e in how many blocks we're going to take action).
477 for mut req in preprocessed_requests {
478 if let Some((new_timer, new_feerate, tx)) = self.generate_claim_tx(cur_height, &req, &*fee_estimator, &*logger) {
479 req.set_timer(new_timer);
480 req.set_feerate(new_feerate);
481 let txid = tx.txid();
482 for k in req.outpoints() {
483 log_info!(logger, "Registering claiming request for {}:{}", k.txid, k.vout);
484 self.claimable_outpoints.insert(k.clone(), (txid, conf_height));
486 self.pending_claim_requests.insert(txid, req);
487 log_info!(logger, "Broadcasting onchain {}", log_tx!(tx));
488 broadcaster.broadcast_transaction(&tx);
492 let mut bump_candidates = HashMap::new();
493 for tx in txn_matched {
494 // Scan all input to verify is one of the outpoint spent is of interest for us
495 let mut claimed_outputs_material = Vec::new();
496 for inp in &tx.input {
497 if let Some(first_claim_txid_height) = self.claimable_outpoints.get(&inp.previous_output) {
498 // If outpoint has claim request pending on it...
499 if let Some(request) = self.pending_claim_requests.get_mut(&first_claim_txid_height.0) {
500 //... we need to verify equality between transaction outpoints and claim request
501 // outpoints to know if transaction is the original claim or a bumped one issued
503 let mut set_equality = true;
504 if request.outpoints().len() != tx.input.len() {
505 set_equality = false;
507 for (claim_inp, tx_inp) in request.outpoints().iter().zip(tx.input.iter()) {
508 if **claim_inp != tx_inp.previous_output {
509 set_equality = false;
514 macro_rules! clean_claim_request_after_safety_delay {
516 let entry = OnchainEventEntry {
519 event: OnchainEvent::Claim { claim_request: first_claim_txid_height.0.clone() }
521 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
522 self.onchain_events_awaiting_threshold_conf.push(entry);
527 // If this is our transaction (or our counterparty spent all the outputs
528 // before we could anyway with same inputs order than us), wait for
529 // ANTI_REORG_DELAY and clean the RBF tracking map.
531 clean_claim_request_after_safety_delay!();
532 } else { // If false, generate new claim request with update outpoint set
533 let mut at_least_one_drop = false;
534 for input in tx.input.iter() {
535 if let Some(package) = request.split_package(&input.previous_output) {
536 claimed_outputs_material.push(package);
537 at_least_one_drop = true;
539 // If there are no outpoints left to claim in this request, drop it entirely after ANTI_REORG_DELAY.
540 if request.outpoints().is_empty() {
541 clean_claim_request_after_safety_delay!();
544 //TODO: recompute soonest_timelock to avoid wasting a bit on fees
545 if at_least_one_drop {
546 bump_candidates.insert(first_claim_txid_height.0.clone(), request.clone());
549 break; //No need to iterate further, either tx is our or their
551 panic!("Inconsistencies between pending_claim_requests map and claimable_outpoints map");
555 for package in claimed_outputs_material.drain(..) {
556 let entry = OnchainEventEntry {
559 event: OnchainEvent::ContentiousOutpoint { package },
561 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
562 self.onchain_events_awaiting_threshold_conf.push(entry);
567 // After security delay, either our claim tx got enough confs or outpoint is definetely out of reach
568 let onchain_events_awaiting_threshold_conf =
569 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
570 for entry in onchain_events_awaiting_threshold_conf {
571 if entry.has_reached_confirmation_threshold(cur_height) {
573 OnchainEvent::Claim { claim_request } => {
574 // We may remove a whole set of claim outpoints here, as these one may have
575 // been aggregated in a single tx and claimed so atomically
576 if let Some(request) = self.pending_claim_requests.remove(&claim_request) {
577 for outpoint in request.outpoints() {
578 log_debug!(logger, "Removing claim tracking for {} due to maturation of claim tx {}.", outpoint, claim_request);
579 self.claimable_outpoints.remove(&outpoint);
583 OnchainEvent::ContentiousOutpoint { package } => {
584 log_debug!(logger, "Removing claim tracking due to maturation of claim tx for outpoints:");
585 log_debug!(logger, " {:?}", package.outpoints());
586 self.claimable_outpoints.remove(&package.outpoints()[0]);
590 self.onchain_events_awaiting_threshold_conf.push(entry);
594 // Check if any pending claim request must be rescheduled
595 for (first_claim_txid, ref request) in self.pending_claim_requests.iter() {
596 if let Some(h) = request.timer() {
598 bump_candidates.insert(*first_claim_txid, (*request).clone());
603 // Build, bump and rebroadcast tx accordingly
604 log_trace!(logger, "Bumping {} candidates", bump_candidates.len());
605 for (first_claim_txid, request) in bump_candidates.iter() {
606 if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(cur_height, &request, &*fee_estimator, &*logger) {
607 log_info!(logger, "Broadcasting RBF-bumped onchain {}", log_tx!(bump_tx));
608 broadcaster.broadcast_transaction(&bump_tx);
609 if let Some(request) = self.pending_claim_requests.get_mut(first_claim_txid) {
610 request.set_timer(new_timer);
611 request.set_feerate(new_feerate);
617 pub(crate) fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
621 fee_estimator: &LowerBoundedFeeEstimator<F>,
624 B::Target: BroadcasterInterface,
625 F::Target: FeeEstimator,
628 let mut height = None;
629 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
630 if entry.txid == *txid {
631 height = Some(entry.height);
636 if let Some(height) = height {
637 self.block_disconnected(height, broadcaster, fee_estimator, logger);
641 pub(crate) fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, broadcaster: B, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: L)
642 where B::Target: BroadcasterInterface,
643 F::Target: FeeEstimator,
646 let mut bump_candidates = HashMap::new();
647 let onchain_events_awaiting_threshold_conf =
648 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
649 for entry in onchain_events_awaiting_threshold_conf {
650 if entry.height >= height {
651 //- our claim tx on a commitment tx output
652 //- resurect outpoint back in its claimable set and regenerate tx
654 OnchainEvent::ContentiousOutpoint { package } => {
655 if let Some(ancestor_claimable_txid) = self.claimable_outpoints.get(&package.outpoints()[0]) {
656 if let Some(request) = self.pending_claim_requests.get_mut(&ancestor_claimable_txid.0) {
657 request.merge_package(package);
658 // Using a HashMap guarantee us than if we have multiple outpoints getting
659 // resurrected only one bump claim tx is going to be broadcast
660 bump_candidates.insert(ancestor_claimable_txid.clone(), request.clone());
667 self.onchain_events_awaiting_threshold_conf.push(entry);
670 for (_, request) in bump_candidates.iter_mut() {
671 if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &request, fee_estimator, &&*logger) {
672 request.set_timer(new_timer);
673 request.set_feerate(new_feerate);
674 log_info!(logger, "Broadcasting onchain {}", log_tx!(bump_tx));
675 broadcaster.broadcast_transaction(&bump_tx);
678 for (ancestor_claim_txid, request) in bump_candidates.drain() {
679 self.pending_claim_requests.insert(ancestor_claim_txid.0, request);
681 //TODO: if we implement cross-block aggregated claim transaction we need to refresh set of outpoints and regenerate tx but
682 // right now if one of the outpoint get disconnected, just erase whole pending claim request.
683 let mut remove_request = Vec::new();
684 self.claimable_outpoints.retain(|_, ref v|
686 remove_request.push(v.0.clone());
689 for req in remove_request {
690 self.pending_claim_requests.remove(&req);
694 pub(crate) fn is_output_spend_pending(&self, outpoint: &BitcoinOutPoint) -> bool {
695 self.claimable_outpoints.get(outpoint).is_some()
698 pub(crate) fn get_relevant_txids(&self) -> Vec<Txid> {
699 let mut txids: Vec<Txid> = self.onchain_events_awaiting_threshold_conf
701 .map(|entry| entry.txid)
703 txids.sort_unstable();
708 pub(crate) fn provide_latest_holder_tx(&mut self, tx: HolderCommitmentTransaction) {
709 self.prev_holder_commitment = Some(replace(&mut self.holder_commitment, tx));
710 self.holder_htlc_sigs = None;
713 // Normally holder HTLCs are signed at the same time as the holder commitment tx. However,
714 // in some configurations, the holder commitment tx has been signed and broadcast by a
715 // ChannelMonitor replica, so we handle that case here.
716 fn sign_latest_holder_htlcs(&mut self) {
717 if self.holder_htlc_sigs.is_none() {
718 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
719 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, sigs));
723 // Normally only the latest commitment tx and HTLCs need to be signed. However, in some
724 // configurations we may have updated our holder commitment but a replica of the ChannelMonitor
725 // broadcast the previous one before we sync with it. We handle that case here.
726 fn sign_prev_holder_htlcs(&mut self) {
727 if self.prev_holder_htlc_sigs.is_none() {
728 if let Some(ref holder_commitment) = self.prev_holder_commitment {
729 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign previous holder commitment");
730 self.prev_holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, sigs));
735 fn extract_holder_sigs(holder_commitment: &HolderCommitmentTransaction, sigs: Vec<Signature>) -> Vec<Option<(usize, Signature)>> {
736 let mut ret = Vec::new();
737 for (htlc_idx, (holder_sig, htlc)) in sigs.iter().zip(holder_commitment.htlcs().iter()).enumerate() {
738 let tx_idx = htlc.transaction_output_index.unwrap();
739 if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
740 ret[tx_idx as usize] = Some((htlc_idx, holder_sig.clone()));
745 //TODO: getting lastest holder transactions should be infallible and result in us "force-closing the channel", but we may
746 // have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after Channel::get_outbound_funding_created,
747 // before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
748 // to monitor before.
749 pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
750 let (sig, htlc_sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
751 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
752 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
755 #[cfg(any(test, feature="unsafe_revoked_tx_signing"))]
756 pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
757 let (sig, htlc_sigs) = self.signer.unsafe_sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
758 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
759 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
762 pub(crate) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
763 let mut htlc_tx = None;
764 let commitment_txid = self.holder_commitment.trust().txid();
765 // Check if the HTLC spends from the current holder commitment
766 if commitment_txid == outp.txid {
767 self.sign_latest_holder_htlcs();
768 if let &Some(ref htlc_sigs) = &self.holder_htlc_sigs {
769 let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
770 let trusted_tx = self.holder_commitment.trust();
771 let counterparty_htlc_sig = self.holder_commitment.counterparty_htlc_sigs[*htlc_idx];
772 htlc_tx = Some(trusted_tx
773 .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
776 // If the HTLC doesn't spend the current holder commitment, check if it spends the previous one
777 if htlc_tx.is_none() && self.prev_holder_commitment.is_some() {
778 let commitment_txid = self.prev_holder_commitment.as_ref().unwrap().trust().txid();
779 if commitment_txid == outp.txid {
780 self.sign_prev_holder_htlcs();
781 if let &Some(ref htlc_sigs) = &self.prev_holder_htlc_sigs {
782 let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
783 let holder_commitment = self.prev_holder_commitment.as_ref().unwrap();
784 let trusted_tx = holder_commitment.trust();
785 let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[*htlc_idx];
786 htlc_tx = Some(trusted_tx
787 .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
794 pub(crate) fn opt_anchors(&self) -> bool {
795 self.channel_transaction_parameters.opt_anchors.is_some()
798 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
799 pub(crate) fn unsafe_get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
800 let latest_had_sigs = self.holder_htlc_sigs.is_some();
801 let prev_had_sigs = self.prev_holder_htlc_sigs.is_some();
802 let ret = self.get_fully_signed_htlc_tx(outp, preimage);
803 if !latest_had_sigs {
804 self.holder_htlc_sigs = None;
807 self.prev_holder_htlc_sigs = None;