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, 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};
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, Writer, Writeable, VecWriter};
36 use alloc::collections::BTreeMap;
37 use std::collections::HashMap;
40 use core::mem::replace;
42 const MAX_ALLOC_SIZE: usize = 64*1024;
44 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
45 /// transaction causing it.
47 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
49 struct OnchainEventEntry {
55 impl OnchainEventEntry {
56 fn confirmation_threshold(&self) -> u32 {
57 self.height + ANTI_REORG_DELAY - 1
60 fn has_reached_confirmation_threshold(&self, height: u32) -> bool {
61 height >= self.confirmation_threshold()
65 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
66 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
69 /// Outpoint under claim process by our own tx, once this one get enough confirmations, we remove it from
70 /// bump-txn candidate buffer.
74 /// Claim tx aggregate multiple claimable outpoints. One of the outpoint may be claimed by a counterparty party tx.
75 /// In this case, we need to drop the outpoint and regenerate a new claim tx. By safety, we keep tracking
76 /// the outpoint to be sure to resurect it back to the claim tx if reorgs happen.
78 package: PackageTemplate,
82 impl_writeable_tlv_based!(OnchainEventEntry, {
88 impl_writeable_tlv_based_enum!(OnchainEvent,
92 (1, ContentiousOutpoint) => {
97 impl Readable for Option<Vec<Option<(usize, Signature)>>> {
98 fn read<R: ::std::io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
99 match Readable::read(reader)? {
102 let vlen: u64 = Readable::read(reader)?;
103 let mut ret = Vec::with_capacity(cmp::min(vlen as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<Option<(usize, Signature)>>()));
105 ret.push(match Readable::read(reader)? {
107 1u8 => Some((<u64 as Readable>::read(reader)? as usize, Readable::read(reader)?)),
108 _ => return Err(DecodeError::InvalidValue)
113 _ => Err(DecodeError::InvalidValue),
118 impl Writeable for Option<Vec<Option<(usize, Signature)>>> {
119 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
123 (vec.len() as u64).write(writer)?;
124 for opt in vec.iter() {
126 &Some((ref idx, ref sig)) => {
128 (*idx as u64).write(writer)?;
131 &None => 0u8.write(writer)?,
135 &None => 0u8.write(writer)?,
142 /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
143 /// do RBF bumping if possible.
144 pub struct OnchainTxHandler<ChannelSigner: Sign> {
145 destination_script: Script,
146 holder_commitment: HolderCommitmentTransaction,
147 // holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
148 // transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
149 // the set of HTLCs in the HolderCommitmentTransaction.
150 holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
151 prev_holder_commitment: Option<HolderCommitmentTransaction>,
152 prev_holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
154 pub(super) signer: ChannelSigner,
155 pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
157 // Used to track claiming requests. If claim tx doesn't confirm before height timer expiration we need to bump
158 // it (RBF or CPFP). If an input has been part of an aggregate tx at first claim try, we need to keep it within
159 // another bumped aggregate tx to comply with RBF rules. We may have multiple claiming txn in the flight for the
160 // same set of outpoints. One of the outpoints may be spent by a transaction not issued by us. That's why at
161 // block connection we scan all inputs and if any of them is among a set of a claiming request we test for set
162 // equality between spending transaction and claim request. If true, it means transaction was one our claiming one
163 // after a security delay of 6 blocks we remove pending claim request. If false, it means transaction wasn't and
164 // we need to regenerate new claim request with reduced set of still-claimable outpoints.
165 // Key is identifier of the pending claim request, i.e the txid of the initial claiming transaction generated by
166 // us and is immutable until all outpoint of the claimable set are post-anti-reorg-delay solved.
167 // Entry is cache of elements need to generate a bumped claiming transaction (see ClaimTxBumpMaterial)
168 #[cfg(test)] // Used in functional_test to verify sanitization
169 pub(crate) pending_claim_requests: HashMap<Txid, PackageTemplate>,
171 pending_claim_requests: HashMap<Txid, PackageTemplate>,
173 // Used to link outpoints claimed in a connected block to a pending claim request.
174 // Key is outpoint than monitor parsing has detected we have keys/scripts to claim
175 // Value is (pending claim request identifier, confirmation_block), identifier
176 // is txid of the initial claiming transaction and is immutable until outpoint is
177 // post-anti-reorg-delay solved, confirmaiton_block is used to erase entry if
178 // block with output gets disconnected.
179 #[cfg(test)] // Used in functional_test to verify sanitization
180 pub claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
182 claimable_outpoints: HashMap<BitcoinOutPoint, (Txid, u32)>,
184 locktimed_packages: BTreeMap<u32, Vec<PackageTemplate>>,
186 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
188 pub(super) secp_ctx: Secp256k1<secp256k1::All>,
191 const SERIALIZATION_VERSION: u8 = 1;
192 const MIN_SERIALIZATION_VERSION: u8 = 1;
194 impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
195 pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), ::std::io::Error> {
196 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
198 self.destination_script.write(writer)?;
199 self.holder_commitment.write(writer)?;
200 self.holder_htlc_sigs.write(writer)?;
201 self.prev_holder_commitment.write(writer)?;
202 self.prev_holder_htlc_sigs.write(writer)?;
204 self.channel_transaction_parameters.write(writer)?;
206 let mut key_data = VecWriter(Vec::new());
207 self.signer.write(&mut key_data)?;
208 assert!(key_data.0.len() < core::usize::MAX);
209 assert!(key_data.0.len() < core::u32::MAX as usize);
210 (key_data.0.len() as u32).write(writer)?;
211 writer.write_all(&key_data.0[..])?;
213 writer.write_all(&byte_utils::be64_to_array(self.pending_claim_requests.len() as u64))?;
214 for (ref ancestor_claim_txid, request) in self.pending_claim_requests.iter() {
215 ancestor_claim_txid.write(writer)?;
216 request.write(writer)?;
219 writer.write_all(&byte_utils::be64_to_array(self.claimable_outpoints.len() as u64))?;
220 for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
222 claim_and_height.0.write(writer)?;
223 claim_and_height.1.write(writer)?;
226 writer.write_all(&byte_utils::be64_to_array(self.locktimed_packages.len() as u64))?;
227 for (ref locktime, ref packages) in self.locktimed_packages.iter() {
228 locktime.write(writer)?;
229 writer.write_all(&byte_utils::be64_to_array(packages.len() as u64))?;
230 for ref package in packages.iter() {
231 package.write(writer)?;
235 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
236 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
237 entry.write(writer)?;
240 write_tlv_fields!(writer, {}, {});
245 impl<'a, K: KeysInterface> ReadableArgs<&'a K> for OnchainTxHandler<K::Signer> {
246 fn read<R: ::std::io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
247 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
249 let destination_script = Readable::read(reader)?;
251 let holder_commitment = Readable::read(reader)?;
252 let holder_htlc_sigs = Readable::read(reader)?;
253 let prev_holder_commitment = Readable::read(reader)?;
254 let prev_holder_htlc_sigs = Readable::read(reader)?;
256 let channel_parameters = Readable::read(reader)?;
258 let keys_len: u32 = Readable::read(reader)?;
259 let mut keys_data = Vec::with_capacity(cmp::min(keys_len as usize, MAX_ALLOC_SIZE));
260 while keys_data.len() != keys_len as usize {
261 // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
262 let mut data = [0; 1024];
263 let read_slice = &mut data[0..cmp::min(1024, keys_len as usize - keys_data.len())];
264 reader.read_exact(read_slice)?;
265 keys_data.extend_from_slice(read_slice);
267 let signer = keys_manager.read_chan_signer(&keys_data)?;
269 let pending_claim_requests_len: u64 = Readable::read(reader)?;
270 let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
271 for _ in 0..pending_claim_requests_len {
272 pending_claim_requests.insert(Readable::read(reader)?, Readable::read(reader)?);
275 let claimable_outpoints_len: u64 = Readable::read(reader)?;
276 let mut claimable_outpoints = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
277 for _ in 0..claimable_outpoints_len {
278 let outpoint = Readable::read(reader)?;
279 let ancestor_claim_txid = Readable::read(reader)?;
280 let height = Readable::read(reader)?;
281 claimable_outpoints.insert(outpoint, (ancestor_claim_txid, height));
284 let locktimed_packages_len: u64 = Readable::read(reader)?;
285 let mut locktimed_packages = BTreeMap::new();
286 for _ in 0..locktimed_packages_len {
287 let locktime = Readable::read(reader)?;
288 let packages_len: u64 = Readable::read(reader)?;
289 let mut packages = Vec::with_capacity(cmp::min(packages_len as usize, MAX_ALLOC_SIZE / std::mem::size_of::<PackageTemplate>()));
290 for _ in 0..packages_len {
291 packages.push(Readable::read(reader)?);
293 locktimed_packages.insert(locktime, packages);
296 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
297 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
298 for _ in 0..waiting_threshold_conf_len {
299 onchain_events_awaiting_threshold_conf.push(Readable::read(reader)?);
302 read_tlv_fields!(reader, {}, {});
304 let mut secp_ctx = Secp256k1::new();
305 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
307 Ok(OnchainTxHandler {
311 prev_holder_commitment,
312 prev_holder_htlc_sigs,
314 channel_transaction_parameters: channel_parameters,
317 pending_claim_requests,
318 onchain_events_awaiting_threshold_conf,
324 impl<ChannelSigner: Sign> OnchainTxHandler<ChannelSigner> {
325 pub(crate) fn new(destination_script: Script, signer: ChannelSigner, channel_parameters: ChannelTransactionParameters, holder_commitment: HolderCommitmentTransaction, secp_ctx: Secp256k1<secp256k1::All>) -> Self {
329 holder_htlc_sigs: None,
330 prev_holder_commitment: None,
331 prev_holder_htlc_sigs: None,
333 channel_transaction_parameters: channel_parameters,
334 pending_claim_requests: HashMap::new(),
335 claimable_outpoints: HashMap::new(),
336 locktimed_packages: BTreeMap::new(),
337 onchain_events_awaiting_threshold_conf: Vec::new(),
343 /// 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
344 /// (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.
345 /// Panics if there are signing errors, because signing operations in reaction to on-chain events
346 /// are not expected to fail, and if they do, we may lose funds.
347 fn generate_claim_tx<F: Deref, L: Deref>(&mut self, height: u32, cached_request: &PackageTemplate, fee_estimator: &F, logger: &L) -> Option<(Option<u32>, u64, Transaction)>
348 where F::Target: FeeEstimator,
351 if cached_request.outpoints().len() == 0 { return None } // But don't prune pending claiming request yet, we may have to resurrect HTLCs
353 // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
354 // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
355 let new_timer = Some(cached_request.get_height_timer(height));
356 if cached_request.is_malleable() {
357 let predicted_weight = cached_request.package_weight(&self.destination_script);
358 if let Some((output_value, new_feerate)) = cached_request.compute_package_output(predicted_weight, fee_estimator, logger) {
359 assert!(new_feerate != 0);
361 let transaction = cached_request.finalize_package(self, output_value, self.destination_script.clone(), logger).unwrap();
362 log_trace!(logger, "...with timer {} and feerate {}", new_timer.unwrap(), new_feerate);
363 assert!(predicted_weight >= transaction.get_weight());
364 return Some((new_timer, new_feerate, transaction))
367 // Note: Currently, amounts of holder outputs spending witnesses aren't used
368 // as we can't malleate spending package to increase their feerate. This
369 // should change with the remaining anchor output patchset.
370 if let Some(transaction) = cached_request.finalize_package(self, 0, self.destination_script.clone(), logger) {
371 return Some((None, 0, transaction));
377 /// Upon channelmonitor.block_connected(..) or upon provision of a preimage on the forward link
378 /// for this channel, provide new relevant on-chain transactions and/or new claim requests.
379 /// Formerly this was named `block_connected`, but it is now also used for claiming an HTLC output
380 /// if we receive a preimage after force-close.
381 pub(crate) fn update_claims_view<B: Deref, F: Deref, L: Deref>(&mut self, txn_matched: &[&Transaction], requests: Vec<PackageTemplate>, height: u32, broadcaster: &B, fee_estimator: &F, logger: &L)
382 where B::Target: BroadcasterInterface,
383 F::Target: FeeEstimator,
386 log_trace!(logger, "Updating claims view at height {} with {} matched transactions and {} claim requests", height, txn_matched.len(), requests.len());
387 let mut preprocessed_requests = Vec::with_capacity(requests.len());
388 let mut aggregated_request = None;
390 // Try to aggregate outputs if their timelock expiration isn't imminent (package timelock
391 // <= CLTV_SHARED_CLAIM_BUFFER) and they don't require an immediate nLockTime (aggregable).
392 for req in requests {
393 // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
394 if let Some(_) = self.claimable_outpoints.get(req.outpoints()[0]) {
395 log_trace!(logger, "Ignoring second claim for outpoint {}:{}, already registered its claiming request", req.outpoints()[0].txid, req.outpoints()[0].vout);
397 let timelocked_equivalent_package = self.locktimed_packages.iter().map(|v| v.1.iter()).flatten()
398 .find(|locked_package| locked_package.outpoints() == req.outpoints());
399 if let Some(package) = timelocked_equivalent_package {
400 log_trace!(logger, "Ignoring second claim for outpoint {}:{}, we already have one which we're waiting on a timelock at {} for.",
401 req.outpoints()[0].txid, req.outpoints()[0].vout, package.package_timelock());
405 if req.package_timelock() > height + 1 {
406 log_debug!(logger, "Delaying claim of package until its timelock at {} (current height {}), the following outpoints are spent:", req.package_timelock(), height);
407 for outpoint in req.outpoints() {
408 log_debug!(logger, " Outpoint {}", outpoint);
410 self.locktimed_packages.entry(req.package_timelock()).or_insert(Vec::new()).push(req);
414 log_trace!(logger, "Test if outpoint can be aggregated with expiration {} against {}", req.timelock(), height + CLTV_SHARED_CLAIM_BUFFER);
415 if req.timelock() <= height + CLTV_SHARED_CLAIM_BUFFER || !req.aggregable() {
416 // Don't aggregate if outpoint package timelock is soon or marked as non-aggregable
417 preprocessed_requests.push(req);
418 } else if aggregated_request.is_none() {
419 aggregated_request = Some(req);
421 aggregated_request.as_mut().unwrap().merge_package(req);
425 if let Some(req) = aggregated_request {
426 preprocessed_requests.push(req);
429 // Claim everything up to and including height + 1
430 let remaining_locked_packages = self.locktimed_packages.split_off(&(height + 2));
431 for (pop_height, mut entry) in self.locktimed_packages.iter_mut() {
432 log_trace!(logger, "Restoring delayed claim of package(s) at their timelock at {}.", pop_height);
433 preprocessed_requests.append(&mut entry);
435 self.locktimed_packages = remaining_locked_packages;
437 // Generate claim transactions and track them to bump if necessary at
438 // height timer expiration (i.e in how many blocks we're going to take action).
439 for mut req in preprocessed_requests {
440 if let Some((new_timer, new_feerate, tx)) = self.generate_claim_tx(height, &req, &*fee_estimator, &*logger) {
441 req.set_timer(new_timer);
442 req.set_feerate(new_feerate);
443 let txid = tx.txid();
444 for k in req.outpoints() {
445 log_trace!(logger, "Registering claiming request for {}:{}", k.txid, k.vout);
446 self.claimable_outpoints.insert(k.clone(), (txid, height));
448 self.pending_claim_requests.insert(txid, req);
449 log_trace!(logger, "Broadcasting onchain {}", log_tx!(tx));
450 broadcaster.broadcast_transaction(&tx);
454 let mut bump_candidates = HashMap::new();
455 for tx in txn_matched {
456 // Scan all input to verify is one of the outpoint spent is of interest for us
457 let mut claimed_outputs_material = Vec::new();
458 for inp in &tx.input {
459 if let Some(first_claim_txid_height) = self.claimable_outpoints.get(&inp.previous_output) {
460 // If outpoint has claim request pending on it...
461 if let Some(request) = self.pending_claim_requests.get_mut(&first_claim_txid_height.0) {
462 //... we need to verify equality between transaction outpoints and claim request
463 // outpoints to know if transaction is the original claim or a bumped one issued
465 let mut set_equality = true;
466 if request.outpoints().len() != tx.input.len() {
467 set_equality = false;
469 for (claim_inp, tx_inp) in request.outpoints().iter().zip(tx.input.iter()) {
470 if **claim_inp != tx_inp.previous_output {
471 set_equality = false;
476 macro_rules! clean_claim_request_after_safety_delay {
478 let entry = OnchainEventEntry {
481 event: OnchainEvent::Claim { claim_request: first_claim_txid_height.0.clone() }
483 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
484 self.onchain_events_awaiting_threshold_conf.push(entry);
489 // If this is our transaction (or our counterparty spent all the outputs
490 // before we could anyway with same inputs order than us), wait for
491 // ANTI_REORG_DELAY and clean the RBF tracking map.
493 clean_claim_request_after_safety_delay!();
494 } else { // If false, generate new claim request with update outpoint set
495 let mut at_least_one_drop = false;
496 for input in tx.input.iter() {
497 if let Some(package) = request.split_package(&input.previous_output) {
498 claimed_outputs_material.push(package);
499 at_least_one_drop = true;
501 // If there are no outpoints left to claim in this request, drop it entirely after ANTI_REORG_DELAY.
502 if request.outpoints().is_empty() {
503 clean_claim_request_after_safety_delay!();
506 //TODO: recompute soonest_timelock to avoid wasting a bit on fees
507 if at_least_one_drop {
508 bump_candidates.insert(first_claim_txid_height.0.clone(), request.clone());
511 break; //No need to iterate further, either tx is our or their
513 panic!("Inconsistencies between pending_claim_requests map and claimable_outpoints map");
517 for package in claimed_outputs_material.drain(..) {
518 let entry = OnchainEventEntry {
521 event: OnchainEvent::ContentiousOutpoint { package },
523 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
524 self.onchain_events_awaiting_threshold_conf.push(entry);
529 // After security delay, either our claim tx got enough confs or outpoint is definetely out of reach
530 let onchain_events_awaiting_threshold_conf =
531 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
532 for entry in onchain_events_awaiting_threshold_conf {
533 if entry.has_reached_confirmation_threshold(height) {
535 OnchainEvent::Claim { claim_request } => {
536 // We may remove a whole set of claim outpoints here, as these one may have
537 // been aggregated in a single tx and claimed so atomically
538 if let Some(request) = self.pending_claim_requests.remove(&claim_request) {
539 for outpoint in request.outpoints() {
540 self.claimable_outpoints.remove(&outpoint);
544 OnchainEvent::ContentiousOutpoint { package } => {
545 self.claimable_outpoints.remove(&package.outpoints()[0]);
549 self.onchain_events_awaiting_threshold_conf.push(entry);
553 // Check if any pending claim request must be rescheduled
554 for (first_claim_txid, ref request) in self.pending_claim_requests.iter() {
555 if let Some(h) = request.timer() {
557 bump_candidates.insert(*first_claim_txid, (*request).clone());
562 // Build, bump and rebroadcast tx accordingly
563 log_trace!(logger, "Bumping {} candidates", bump_candidates.len());
564 for (first_claim_txid, request) in bump_candidates.iter() {
565 if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &request, &*fee_estimator, &*logger) {
566 log_trace!(logger, "Broadcasting onchain {}", log_tx!(bump_tx));
567 broadcaster.broadcast_transaction(&bump_tx);
568 if let Some(request) = self.pending_claim_requests.get_mut(first_claim_txid) {
569 request.set_timer(new_timer);
570 request.set_feerate(new_feerate);
576 pub(crate) fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
583 B::Target: BroadcasterInterface,
584 F::Target: FeeEstimator,
587 let mut height = None;
588 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
589 if entry.txid == *txid {
590 height = Some(entry.height);
595 if let Some(height) = height {
596 self.block_disconnected(height, broadcaster, fee_estimator, logger);
600 pub(crate) fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, broadcaster: B, fee_estimator: F, logger: L)
601 where B::Target: BroadcasterInterface,
602 F::Target: FeeEstimator,
605 let mut bump_candidates = HashMap::new();
606 let onchain_events_awaiting_threshold_conf =
607 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
608 for entry in onchain_events_awaiting_threshold_conf {
609 if entry.height >= height {
610 //- our claim tx on a commitment tx output
611 //- resurect outpoint back in its claimable set and regenerate tx
613 OnchainEvent::ContentiousOutpoint { package } => {
614 if let Some(ancestor_claimable_txid) = self.claimable_outpoints.get(&package.outpoints()[0]) {
615 if let Some(request) = self.pending_claim_requests.get_mut(&ancestor_claimable_txid.0) {
616 request.merge_package(package);
617 // Using a HashMap guarantee us than if we have multiple outpoints getting
618 // resurrected only one bump claim tx is going to be broadcast
619 bump_candidates.insert(ancestor_claimable_txid.clone(), request.clone());
626 self.onchain_events_awaiting_threshold_conf.push(entry);
629 for (_, request) in bump_candidates.iter_mut() {
630 if let Some((new_timer, new_feerate, bump_tx)) = self.generate_claim_tx(height, &request, &&*fee_estimator, &&*logger) {
631 request.set_timer(new_timer);
632 request.set_feerate(new_feerate);
633 log_info!(logger, "Broadcasting onchain {}", log_tx!(bump_tx));
634 broadcaster.broadcast_transaction(&bump_tx);
637 for (ancestor_claim_txid, request) in bump_candidates.drain() {
638 self.pending_claim_requests.insert(ancestor_claim_txid.0, request);
640 //TODO: if we implement cross-block aggregated claim transaction we need to refresh set of outpoints and regenerate tx but
641 // right now if one of the outpoint get disconnected, just erase whole pending claim request.
642 let mut remove_request = Vec::new();
643 self.claimable_outpoints.retain(|_, ref v|
645 remove_request.push(v.0.clone());
648 for req in remove_request {
649 self.pending_claim_requests.remove(&req);
653 pub(crate) fn get_relevant_txids(&self) -> Vec<Txid> {
654 let mut txids: Vec<Txid> = self.onchain_events_awaiting_threshold_conf
656 .map(|entry| entry.txid)
658 txids.sort_unstable();
663 pub(crate) fn provide_latest_holder_tx(&mut self, tx: HolderCommitmentTransaction) {
664 self.prev_holder_commitment = Some(replace(&mut self.holder_commitment, tx));
665 self.holder_htlc_sigs = None;
668 // Normally holder HTLCs are signed at the same time as the holder commitment tx. However,
669 // in some configurations, the holder commitment tx has been signed and broadcast by a
670 // ChannelMonitor replica, so we handle that case here.
671 fn sign_latest_holder_htlcs(&mut self) {
672 if self.holder_htlc_sigs.is_none() {
673 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
674 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, sigs));
678 // Normally only the latest commitment tx and HTLCs need to be signed. However, in some
679 // configurations we may have updated our holder commitment but a replica of the ChannelMonitor
680 // broadcast the previous one before we sync with it. We handle that case here.
681 fn sign_prev_holder_htlcs(&mut self) {
682 if self.prev_holder_htlc_sigs.is_none() {
683 if let Some(ref holder_commitment) = self.prev_holder_commitment {
684 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign previous holder commitment");
685 self.prev_holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, sigs));
690 fn extract_holder_sigs(holder_commitment: &HolderCommitmentTransaction, sigs: Vec<Signature>) -> Vec<Option<(usize, Signature)>> {
691 let mut ret = Vec::new();
692 for (htlc_idx, (holder_sig, htlc)) in sigs.iter().zip(holder_commitment.htlcs().iter()).enumerate() {
693 let tx_idx = htlc.transaction_output_index.unwrap();
694 if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
695 ret[tx_idx as usize] = Some((htlc_idx, holder_sig.clone()));
700 //TODO: getting lastest holder transactions should be infallible and result in us "force-closing the channel", but we may
701 // have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after Channel::get_outbound_funding_created,
702 // before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
703 // to monitor before.
704 pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
705 let (sig, htlc_sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
706 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
707 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
710 #[cfg(any(test, feature="unsafe_revoked_tx_signing"))]
711 pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
712 let (sig, htlc_sigs) = self.signer.unsafe_sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
713 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
714 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
717 pub(crate) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
718 let mut htlc_tx = None;
719 let commitment_txid = self.holder_commitment.trust().txid();
720 // Check if the HTLC spends from the current holder commitment
721 if commitment_txid == outp.txid {
722 self.sign_latest_holder_htlcs();
723 if let &Some(ref htlc_sigs) = &self.holder_htlc_sigs {
724 let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
725 let trusted_tx = self.holder_commitment.trust();
726 let counterparty_htlc_sig = self.holder_commitment.counterparty_htlc_sigs[*htlc_idx];
727 htlc_tx = Some(trusted_tx
728 .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
731 // If the HTLC doesn't spend the current holder commitment, check if it spends the previous one
732 if htlc_tx.is_none() && self.prev_holder_commitment.is_some() {
733 let commitment_txid = self.prev_holder_commitment.as_ref().unwrap().trust().txid();
734 if commitment_txid == outp.txid {
735 self.sign_prev_holder_htlcs();
736 if let &Some(ref htlc_sigs) = &self.prev_holder_htlc_sigs {
737 let &(ref htlc_idx, ref htlc_sig) = htlc_sigs[outp.vout as usize].as_ref().unwrap();
738 let holder_commitment = self.prev_holder_commitment.as_ref().unwrap();
739 let trusted_tx = holder_commitment.trust();
740 let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[*htlc_idx];
741 htlc_tx = Some(trusted_tx
742 .get_signed_htlc_tx(&self.channel_transaction_parameters.as_holder_broadcastable(), *htlc_idx, &counterparty_htlc_sig, htlc_sig, preimage));
749 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
750 pub(crate) fn unsafe_get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
751 let latest_had_sigs = self.holder_htlc_sigs.is_some();
752 let prev_had_sigs = self.prev_holder_htlc_sigs.is_some();
753 let ret = self.get_fully_signed_htlc_tx(outp, preimage);
754 if !latest_had_sigs {
755 self.holder_htlc_sigs = None;
758 self.prev_holder_htlc_sigs = None;