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::PackedLockTime;
16 use bitcoin::blockdata::transaction::Transaction;
17 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
18 use bitcoin::blockdata::script::Script;
19 use bitcoin::hashes::{Hash, HashEngine};
20 use bitcoin::hashes::sha256::Hash as Sha256;
21 use bitcoin::hash_types::{Txid, BlockHash};
22 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
23 use bitcoin::secp256k1;
25 use crate::chain::chaininterface::compute_feerate_sat_per_1000_weight;
26 use crate::events::bump_transaction::{ChannelDerivationParameters, HTLCDescriptor};
27 use crate::sign::{ChannelSigner, EntropySource, SignerProvider};
28 use crate::ln::msgs::DecodeError;
29 use crate::ln::PaymentPreimage;
30 use crate::ln::chan_utils::{self, ChannelTransactionParameters, HTLCOutputInCommitment, HolderCommitmentTransaction};
31 use crate::chain::ClaimId;
32 use crate::chain::chaininterface::{ConfirmationTarget, FeeEstimator, BroadcasterInterface, LowerBoundedFeeEstimator};
33 use crate::chain::channelmonitor::{ANTI_REORG_DELAY, CLTV_SHARED_CLAIM_BUFFER};
34 use crate::sign::WriteableEcdsaChannelSigner;
35 use crate::chain::package::{PackageSolvingData, PackageTemplate};
36 use crate::util::logger::Logger;
37 use crate::util::ser::{Readable, ReadableArgs, MaybeReadable, UpgradableRequired, Writer, Writeable, VecWriter};
40 use crate::prelude::*;
41 use alloc::collections::BTreeMap;
44 use core::mem::replace;
46 use crate::ln::features::ChannelTypeFeatures;
48 const MAX_ALLOC_SIZE: usize = 64*1024;
50 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
51 /// transaction causing it.
53 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
54 #[derive(Clone, PartialEq, Eq)]
55 struct OnchainEventEntry {
58 block_hash: Option<BlockHash>, // Added as optional, will be filled in for any entry generated on 0.0.113 or after
62 impl OnchainEventEntry {
63 fn confirmation_threshold(&self) -> u32 {
64 self.height + ANTI_REORG_DELAY - 1
67 fn has_reached_confirmation_threshold(&self, height: u32) -> bool {
68 height >= self.confirmation_threshold()
72 /// Events for claims the [`OnchainTxHandler`] has generated. Once the events are considered safe
73 /// from a chain reorg, the [`OnchainTxHandler`] will act accordingly.
74 #[derive(Clone, PartialEq, Eq)]
76 /// A pending request has been claimed by a transaction spending the exact same set of outpoints
77 /// as the request. This claim can either be ours or from the counterparty. Once the claiming
78 /// transaction has met [`ANTI_REORG_DELAY`] confirmations, we consider it final and remove the
83 /// The counterparty has claimed an outpoint from one of our pending requests through a
84 /// different transaction than ours. If our transaction was attempting to claim multiple
85 /// outputs, we need to drop the outpoint claimed by the counterparty and regenerate a new claim
86 /// transaction for ourselves. We keep tracking, separately, the outpoint claimed by the
87 /// counterparty up to [`ANTI_REORG_DELAY`] confirmations to ensure we attempt to re-claim it
88 /// if the counterparty's claim is reorged from the chain.
90 package: PackageTemplate,
94 impl Writeable for OnchainEventEntry {
95 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
96 write_tlv_fields!(writer, {
97 (0, self.txid, required),
98 (1, self.block_hash, option),
99 (2, self.height, required),
100 (4, self.event, required),
106 impl MaybeReadable for OnchainEventEntry {
107 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
108 let mut txid = Txid::all_zeros();
110 let mut block_hash = None;
111 let mut event = UpgradableRequired(None);
112 read_tlv_fields!(reader, {
114 (1, block_hash, option),
115 (2, height, required),
116 (4, event, upgradable_required),
118 Ok(Some(Self { txid, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
122 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
124 (0, claim_id, required),
126 (1, ContentiousOutpoint) => {
127 (0, package, required),
131 impl Readable for Option<Vec<Option<(usize, Signature)>>> {
132 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
133 match Readable::read(reader)? {
136 let vlen: u64 = Readable::read(reader)?;
137 let mut ret = Vec::with_capacity(cmp::min(vlen as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<Option<(usize, Signature)>>()));
139 ret.push(match Readable::read(reader)? {
141 1u8 => Some((<u64 as Readable>::read(reader)? as usize, Readable::read(reader)?)),
142 _ => return Err(DecodeError::InvalidValue)
147 _ => Err(DecodeError::InvalidValue),
152 impl Writeable for Option<Vec<Option<(usize, Signature)>>> {
153 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
157 (vec.len() as u64).write(writer)?;
158 for opt in vec.iter() {
160 &Some((ref idx, ref sig)) => {
162 (*idx as u64).write(writer)?;
165 &None => 0u8.write(writer)?,
169 &None => 0u8.write(writer)?,
175 /// The claim commonly referred to as the pre-signed second-stage HTLC transaction.
176 #[derive(Clone, PartialEq, Eq)]
177 pub(crate) struct ExternalHTLCClaim {
178 pub(crate) commitment_txid: Txid,
179 pub(crate) per_commitment_number: u64,
180 pub(crate) htlc: HTLCOutputInCommitment,
181 pub(crate) preimage: Option<PaymentPreimage>,
182 pub(crate) counterparty_sig: Signature,
185 // Represents the different types of claims for which events are yielded externally to satisfy said
187 #[derive(Clone, PartialEq, Eq)]
188 pub(crate) enum ClaimEvent {
189 /// Event yielded to signal that the commitment transaction fee must be bumped to claim any
190 /// encumbered funds and proceed to HTLC resolution, if any HTLCs exist.
192 package_target_feerate_sat_per_1000_weight: u32,
193 commitment_tx: Transaction,
194 anchor_output_idx: u32,
196 /// Event yielded to signal that the commitment transaction has confirmed and its HTLCs must be
197 /// resolved by broadcasting a transaction with sufficient fee to claim them.
199 target_feerate_sat_per_1000_weight: u32,
200 htlcs: Vec<ExternalHTLCClaim>,
201 tx_lock_time: PackedLockTime,
205 /// Represents the different ways an output can be claimed (i.e., spent to an address under our
206 /// control) onchain.
207 pub(crate) enum OnchainClaim {
208 /// A finalized transaction pending confirmation spending the output to claim.
210 /// An event yielded externally to signal additional inputs must be added to a transaction
211 /// pending confirmation spending the output to claim.
215 /// OnchainTxHandler receives claiming requests, aggregates them if it's sound, broadcast and
216 /// do RBF bumping if possible.
218 pub struct OnchainTxHandler<ChannelSigner: WriteableEcdsaChannelSigner> {
219 channel_value_satoshis: u64,
220 channel_keys_id: [u8; 32],
221 destination_script: Script,
222 holder_commitment: HolderCommitmentTransaction,
223 // holder_htlc_sigs and prev_holder_htlc_sigs are in the order as they appear in the commitment
224 // transaction outputs (hence the Option<>s inside the Vec). The first usize is the index in
225 // the set of HTLCs in the HolderCommitmentTransaction.
226 holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
227 prev_holder_commitment: Option<HolderCommitmentTransaction>,
228 prev_holder_htlc_sigs: Option<Vec<Option<(usize, Signature)>>>,
230 pub(super) signer: ChannelSigner,
231 pub(crate) channel_transaction_parameters: ChannelTransactionParameters,
233 // Used to track claiming requests. If claim tx doesn't confirm before height timer expiration we need to bump
234 // it (RBF or CPFP). If an input has been part of an aggregate tx at first claim try, we need to keep it within
235 // another bumped aggregate tx to comply with RBF rules. We may have multiple claiming txn in the flight for the
236 // same set of outpoints. One of the outpoints may be spent by a transaction not issued by us. That's why at
237 // block connection we scan all inputs and if any of them is among a set of a claiming request we test for set
238 // equality between spending transaction and claim request. If true, it means transaction was one our claiming one
239 // after a security delay of 6 blocks we remove pending claim request. If false, it means transaction wasn't and
240 // we need to regenerate new claim request with reduced set of still-claimable outpoints.
241 // Key is identifier of the pending claim request, i.e the txid of the initial claiming transaction generated by
242 // us and is immutable until all outpoint of the claimable set are post-anti-reorg-delay solved.
243 // Entry is cache of elements need to generate a bumped claiming transaction (see ClaimTxBumpMaterial)
244 #[cfg(test)] // Used in functional_test to verify sanitization
245 pub(crate) pending_claim_requests: HashMap<ClaimId, PackageTemplate>,
247 pending_claim_requests: HashMap<ClaimId, PackageTemplate>,
249 // Used to track external events that need to be forwarded to the `ChainMonitor`. This `Vec`
250 // essentially acts as an insertion-ordered `HashMap` – there should only ever be one occurrence
251 // of a `ClaimId`, which tracks its latest `ClaimEvent`, i.e., if a pending claim exists, and
252 // a new block has been connected, resulting in a new claim, the previous will be replaced with
255 // These external events may be generated in the following cases:
256 // - A channel has been force closed by broadcasting the holder's latest commitment transaction
257 // - A block being connected/disconnected
258 // - Learning the preimage for an HTLC we can claim onchain
259 pending_claim_events: Vec<(ClaimId, ClaimEvent)>,
261 // Used to link outpoints claimed in a connected block to a pending claim request. The keys
262 // represent the outpoints that our `ChannelMonitor` has detected we have keys/scripts to
263 // claim. The values track the pending claim request identifier and the initial confirmation
264 // block height, and are immutable until the outpoint has enough confirmations to meet our
265 // [`ANTI_REORG_DELAY`]. The initial confirmation block height is used to remove the entry if
266 // the block gets disconnected.
267 #[cfg(test)] // Used in functional_test to verify sanitization
268 pub claimable_outpoints: HashMap<BitcoinOutPoint, (ClaimId, u32)>,
270 claimable_outpoints: HashMap<BitcoinOutPoint, (ClaimId, u32)>,
272 locktimed_packages: BTreeMap<u32, Vec<PackageTemplate>>,
274 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
276 pub(super) secp_ctx: Secp256k1<secp256k1::All>,
279 impl<ChannelSigner: WriteableEcdsaChannelSigner> PartialEq for OnchainTxHandler<ChannelSigner> {
280 fn eq(&self, other: &Self) -> bool {
281 // `signer`, `secp_ctx`, and `pending_claim_events` are excluded on purpose.
282 self.channel_value_satoshis == other.channel_value_satoshis &&
283 self.channel_keys_id == other.channel_keys_id &&
284 self.destination_script == other.destination_script &&
285 self.holder_commitment == other.holder_commitment &&
286 self.holder_htlc_sigs == other.holder_htlc_sigs &&
287 self.prev_holder_commitment == other.prev_holder_commitment &&
288 self.prev_holder_htlc_sigs == other.prev_holder_htlc_sigs &&
289 self.channel_transaction_parameters == other.channel_transaction_parameters &&
290 self.pending_claim_requests == other.pending_claim_requests &&
291 self.claimable_outpoints == other.claimable_outpoints &&
292 self.locktimed_packages == other.locktimed_packages &&
293 self.onchain_events_awaiting_threshold_conf == other.onchain_events_awaiting_threshold_conf
297 const SERIALIZATION_VERSION: u8 = 1;
298 const MIN_SERIALIZATION_VERSION: u8 = 1;
300 impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
301 pub(crate) fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
302 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
304 self.destination_script.write(writer)?;
305 self.holder_commitment.write(writer)?;
306 self.holder_htlc_sigs.write(writer)?;
307 self.prev_holder_commitment.write(writer)?;
308 self.prev_holder_htlc_sigs.write(writer)?;
310 self.channel_transaction_parameters.write(writer)?;
312 let mut key_data = VecWriter(Vec::new());
313 self.signer.write(&mut key_data)?;
314 assert!(key_data.0.len() < core::usize::MAX);
315 assert!(key_data.0.len() < core::u32::MAX as usize);
316 (key_data.0.len() as u32).write(writer)?;
317 writer.write_all(&key_data.0[..])?;
319 writer.write_all(&(self.pending_claim_requests.len() as u64).to_be_bytes())?;
320 for (ref ancestor_claim_txid, request) in self.pending_claim_requests.iter() {
321 ancestor_claim_txid.write(writer)?;
322 request.write(writer)?;
325 writer.write_all(&(self.claimable_outpoints.len() as u64).to_be_bytes())?;
326 for (ref outp, ref claim_and_height) in self.claimable_outpoints.iter() {
328 claim_and_height.0.write(writer)?;
329 claim_and_height.1.write(writer)?;
332 writer.write_all(&(self.locktimed_packages.len() as u64).to_be_bytes())?;
333 for (ref locktime, ref packages) in self.locktimed_packages.iter() {
334 locktime.write(writer)?;
335 writer.write_all(&(packages.len() as u64).to_be_bytes())?;
336 for ref package in packages.iter() {
337 package.write(writer)?;
341 writer.write_all(&(self.onchain_events_awaiting_threshold_conf.len() as u64).to_be_bytes())?;
342 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
343 entry.write(writer)?;
346 write_tlv_fields!(writer, {});
351 impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP, u64, [u8; 32])> for OnchainTxHandler<SP::Signer> {
352 fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP, u64, [u8; 32])) -> Result<Self, DecodeError> {
353 let entropy_source = args.0;
354 let signer_provider = args.1;
355 let channel_value_satoshis = args.2;
356 let channel_keys_id = args.3;
358 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
360 let destination_script = Readable::read(reader)?;
362 let holder_commitment = Readable::read(reader)?;
363 let holder_htlc_sigs = Readable::read(reader)?;
364 let prev_holder_commitment = Readable::read(reader)?;
365 let prev_holder_htlc_sigs = Readable::read(reader)?;
367 let channel_parameters = Readable::read(reader)?;
369 // Read the serialized signer bytes, but don't deserialize them, as we'll obtain our signer
370 // by re-deriving the private key material.
371 let keys_len: u32 = Readable::read(reader)?;
372 let mut bytes_read = 0;
373 while bytes_read != keys_len as usize {
374 // Read 1KB at a time to avoid accidentally allocating 4GB on corrupted channel keys
375 let mut data = [0; 1024];
376 let bytes_to_read = cmp::min(1024, keys_len as usize - bytes_read);
377 let read_slice = &mut data[0..bytes_to_read];
378 reader.read_exact(read_slice)?;
379 bytes_read += bytes_to_read;
382 let mut signer = signer_provider.derive_channel_signer(channel_value_satoshis, channel_keys_id);
383 signer.provide_channel_parameters(&channel_parameters);
385 let pending_claim_requests_len: u64 = Readable::read(reader)?;
386 let mut pending_claim_requests = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
387 for _ in 0..pending_claim_requests_len {
388 pending_claim_requests.insert(Readable::read(reader)?, Readable::read(reader)?);
391 let claimable_outpoints_len: u64 = Readable::read(reader)?;
392 let mut claimable_outpoints = HashMap::with_capacity(cmp::min(pending_claim_requests_len as usize, MAX_ALLOC_SIZE / 128));
393 for _ in 0..claimable_outpoints_len {
394 let outpoint = Readable::read(reader)?;
395 let ancestor_claim_txid = Readable::read(reader)?;
396 let height = Readable::read(reader)?;
397 claimable_outpoints.insert(outpoint, (ancestor_claim_txid, height));
400 let locktimed_packages_len: u64 = Readable::read(reader)?;
401 let mut locktimed_packages = BTreeMap::new();
402 for _ in 0..locktimed_packages_len {
403 let locktime = Readable::read(reader)?;
404 let packages_len: u64 = Readable::read(reader)?;
405 let mut packages = Vec::with_capacity(cmp::min(packages_len as usize, MAX_ALLOC_SIZE / core::mem::size_of::<PackageTemplate>()));
406 for _ in 0..packages_len {
407 packages.push(Readable::read(reader)?);
409 locktimed_packages.insert(locktime, packages);
412 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
413 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
414 for _ in 0..waiting_threshold_conf_len {
415 if let Some(val) = MaybeReadable::read(reader)? {
416 onchain_events_awaiting_threshold_conf.push(val);
420 read_tlv_fields!(reader, {});
422 let mut secp_ctx = Secp256k1::new();
423 secp_ctx.seeded_randomize(&entropy_source.get_secure_random_bytes());
425 Ok(OnchainTxHandler {
426 channel_value_satoshis,
431 prev_holder_commitment,
432 prev_holder_htlc_sigs,
434 channel_transaction_parameters: channel_parameters,
437 pending_claim_requests,
438 onchain_events_awaiting_threshold_conf,
439 pending_claim_events: Vec::new(),
445 impl<ChannelSigner: WriteableEcdsaChannelSigner> OnchainTxHandler<ChannelSigner> {
447 channel_value_satoshis: u64, channel_keys_id: [u8; 32], destination_script: Script,
448 signer: ChannelSigner, channel_parameters: ChannelTransactionParameters,
449 holder_commitment: HolderCommitmentTransaction, secp_ctx: Secp256k1<secp256k1::All>
452 channel_value_satoshis,
456 holder_htlc_sigs: None,
457 prev_holder_commitment: None,
458 prev_holder_htlc_sigs: None,
460 channel_transaction_parameters: channel_parameters,
461 pending_claim_requests: HashMap::new(),
462 claimable_outpoints: HashMap::new(),
463 locktimed_packages: BTreeMap::new(),
464 onchain_events_awaiting_threshold_conf: Vec::new(),
465 pending_claim_events: Vec::new(),
470 pub(crate) fn get_prev_holder_commitment_to_self_value(&self) -> Option<u64> {
471 self.prev_holder_commitment.as_ref().map(|commitment| commitment.to_broadcaster_value_sat())
474 pub(crate) fn get_cur_holder_commitment_to_self_value(&self) -> u64 {
475 self.holder_commitment.to_broadcaster_value_sat()
478 pub(crate) fn get_and_clear_pending_claim_events(&mut self) -> Vec<(ClaimId, ClaimEvent)> {
479 let mut events = Vec::new();
480 swap(&mut events, &mut self.pending_claim_events);
484 /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
485 /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
486 /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
487 /// invoking this every 30 seconds, or lower if running in an environment with spotty
488 /// connections, like on mobile.
489 pub(crate) fn rebroadcast_pending_claims<B: Deref, F: Deref, L: Deref>(
490 &mut self, current_height: u32, broadcaster: &B, fee_estimator: &LowerBoundedFeeEstimator<F>,
494 B::Target: BroadcasterInterface,
495 F::Target: FeeEstimator,
498 let mut bump_requests = Vec::with_capacity(self.pending_claim_requests.len());
499 for (claim_id, request) in self.pending_claim_requests.iter() {
500 let inputs = request.outpoints();
501 log_info!(logger, "Triggering rebroadcast/fee-bump for request with inputs {:?}", inputs);
502 bump_requests.push((*claim_id, request.clone()));
504 for (claim_id, request) in bump_requests {
505 self.generate_claim(current_height, &request, false /* force_feerate_bump */, fee_estimator, logger)
506 .map(|(_, new_feerate, claim)| {
507 let mut bumped_feerate = false;
508 if let Some(mut_request) = self.pending_claim_requests.get_mut(&claim_id) {
509 bumped_feerate = request.previous_feerate() > new_feerate;
510 mut_request.set_feerate(new_feerate);
513 OnchainClaim::Tx(tx) => {
514 let log_start = if bumped_feerate { "Broadcasting RBF-bumped" } else { "Rebroadcasting" };
515 log_info!(logger, "{} onchain {}", log_start, log_tx!(tx));
516 broadcaster.broadcast_transactions(&[&tx]);
518 OnchainClaim::Event(event) => {
519 let log_start = if bumped_feerate { "Yielding fee-bumped" } else { "Replaying" };
520 log_info!(logger, "{} onchain event to spend inputs {:?}", log_start,
521 request.outpoints());
522 #[cfg(debug_assertions)] {
523 debug_assert!(request.requires_external_funding());
524 let num_existing = self.pending_claim_events.iter()
525 .filter(|entry| entry.0 == claim_id).count();
526 assert!(num_existing == 0 || num_existing == 1);
528 self.pending_claim_events.retain(|event| event.0 != claim_id);
529 self.pending_claim_events.push((claim_id, event));
536 /// Lightning security model (i.e being able to redeem/timeout HTLC or penalize counterparty
537 /// onchain) lays on the assumption of claim transactions getting confirmed before timelock
538 /// expiration (CSV or CLTV following cases). In case of high-fee spikes, claim tx may get stuck
539 /// in the mempool, so you need to bump its feerate quickly using Replace-By-Fee or
540 /// Child-Pay-For-Parent.
542 /// Panics if there are signing errors, because signing operations in reaction to on-chain
543 /// events are not expected to fail, and if they do, we may lose funds.
544 fn generate_claim<F: Deref, L: Deref>(
545 &mut self, cur_height: u32, cached_request: &PackageTemplate, force_feerate_bump: bool,
546 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L,
547 ) -> Option<(u32, u64, OnchainClaim)>
549 F::Target: FeeEstimator,
552 let request_outpoints = cached_request.outpoints();
553 if request_outpoints.is_empty() {
554 // Don't prune pending claiming request yet, we may have to resurrect HTLCs. Untractable
555 // packages cannot be aggregated and will never be split, so we cannot end up with an
557 debug_assert!(cached_request.is_malleable());
560 // If we've seen transaction inclusion in the chain for all outpoints in our request, we
561 // don't need to continue generating more claims. We'll keep tracking the request to fully
562 // remove it once it reaches the confirmation threshold, or to generate a new claim if the
563 // transaction is reorged out.
564 let mut all_inputs_have_confirmed_spend = true;
565 for outpoint in request_outpoints.iter() {
566 if let Some((request_claim_id, _)) = self.claimable_outpoints.get(*outpoint) {
567 // We check for outpoint spends within claims individually rather than as a set
568 // since requests can have outpoints split off.
569 if !self.onchain_events_awaiting_threshold_conf.iter()
570 .any(|event_entry| if let OnchainEvent::Claim { claim_id } = event_entry.event {
571 *request_claim_id == claim_id
573 // The onchain event is not a claim, keep seeking until we find one.
577 // Either we had no `OnchainEvent::Claim`, or we did but none matched the
578 // outpoint's registered spend.
579 all_inputs_have_confirmed_spend = false;
582 // The request's outpoint spend does not exist yet.
583 all_inputs_have_confirmed_spend = false;
586 if all_inputs_have_confirmed_spend {
590 // Compute new height timer to decide when we need to regenerate a new bumped version of the claim tx (if we
591 // didn't receive confirmation of it before, or not enough reorg-safe depth on top of it).
592 let new_timer = cached_request.get_height_timer(cur_height);
593 if cached_request.is_malleable() {
594 if cached_request.requires_external_funding() {
595 let target_feerate_sat_per_1000_weight = cached_request.compute_package_feerate(
596 fee_estimator, ConfirmationTarget::HighPriority, force_feerate_bump
598 if let Some(htlcs) = cached_request.construct_malleable_package_with_external_funding(self) {
601 target_feerate_sat_per_1000_weight as u64,
602 OnchainClaim::Event(ClaimEvent::BumpHTLC {
603 target_feerate_sat_per_1000_weight,
605 tx_lock_time: PackedLockTime(cached_request.package_locktime(cur_height)),
613 let predicted_weight = cached_request.package_weight(&self.destination_script);
614 if let Some((output_value, new_feerate)) = cached_request.compute_package_output(
615 predicted_weight, self.destination_script.dust_value().to_sat(),
616 force_feerate_bump, fee_estimator, logger,
618 assert!(new_feerate != 0);
620 let transaction = cached_request.finalize_malleable_package(
621 cur_height, self, output_value, self.destination_script.clone(), logger
623 log_trace!(logger, "...with timer {} and feerate {}", new_timer, new_feerate);
624 assert!(predicted_weight >= transaction.weight());
625 return Some((new_timer, new_feerate, OnchainClaim::Tx(transaction)));
628 // Untractable packages cannot have their fees bumped through Replace-By-Fee. Some
629 // packages may support fee bumping through Child-Pays-For-Parent, indicated by those
630 // which require external funding.
631 let mut inputs = cached_request.inputs();
632 debug_assert_eq!(inputs.len(), 1);
633 let tx = match cached_request.finalize_untractable_package(self, logger) {
637 if !cached_request.requires_external_funding() {
638 return Some((new_timer, 0, OnchainClaim::Tx(tx)));
640 return inputs.find_map(|input| match input {
641 // Commitment inputs with anchors support are the only untractable inputs supported
642 // thus far that require external funding.
643 PackageSolvingData::HolderFundingOutput(output) => {
644 debug_assert_eq!(tx.txid(), self.holder_commitment.trust().txid(),
645 "Holder commitment transaction mismatch");
647 let conf_target = ConfirmationTarget::HighPriority;
648 let package_target_feerate_sat_per_1000_weight = cached_request
649 .compute_package_feerate(fee_estimator, conf_target, force_feerate_bump);
650 if let Some(input_amount_sat) = output.funding_amount {
651 let fee_sat = input_amount_sat - tx.output.iter().map(|output| output.value).sum::<u64>();
652 let commitment_tx_feerate_sat_per_1000_weight =
653 compute_feerate_sat_per_1000_weight(fee_sat, tx.weight() as u64);
654 if commitment_tx_feerate_sat_per_1000_weight >= package_target_feerate_sat_per_1000_weight {
655 log_debug!(logger, "Pre-signed {} already has feerate {} sat/kW above required {} sat/kW",
656 log_tx!(tx), commitment_tx_feerate_sat_per_1000_weight,
657 package_target_feerate_sat_per_1000_weight);
658 return Some((new_timer, 0, OnchainClaim::Tx(tx.clone())));
662 // We'll locate an anchor output we can spend within the commitment transaction.
663 let funding_pubkey = &self.channel_transaction_parameters.holder_pubkeys.funding_pubkey;
664 match chan_utils::get_anchor_output(&tx, funding_pubkey) {
665 // An anchor output was found, so we should yield a funding event externally.
667 // TODO: Use a lower confirmation target when both our and the
668 // counterparty's latest commitment don't have any HTLCs present.
671 package_target_feerate_sat_per_1000_weight as u64,
672 OnchainClaim::Event(ClaimEvent::BumpCommitment {
673 package_target_feerate_sat_per_1000_weight,
674 commitment_tx: tx.clone(),
675 anchor_output_idx: idx,
679 // An anchor output was not found. There's nothing we can do other than
680 // attempt to broadcast the transaction with its current fee rate and hope
681 // it confirms. This is essentially the same behavior as a commitment
682 // transaction without anchor outputs.
683 None => Some((new_timer, 0, OnchainClaim::Tx(tx.clone()))),
687 debug_assert!(false, "Only HolderFundingOutput inputs should be untractable and require external funding");
695 /// Upon channelmonitor.block_connected(..) or upon provision of a preimage on the forward link
696 /// for this channel, provide new relevant on-chain transactions and/or new claim requests.
697 /// Together with `update_claims_view_from_matched_txn` this used to be named
698 /// `block_connected`, but it is now also used for claiming an HTLC output if we receive a
699 /// preimage after force-close.
701 /// `conf_height` represents the height at which the request was generated. This
702 /// does not need to equal the current blockchain tip height, which should be provided via
703 /// `cur_height`, however it must never be higher than `cur_height`.
704 pub(crate) fn update_claims_view_from_requests<B: Deref, F: Deref, L: Deref>(
705 &mut self, requests: Vec<PackageTemplate>, conf_height: u32, cur_height: u32,
706 broadcaster: &B, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
708 B::Target: BroadcasterInterface,
709 F::Target: FeeEstimator,
712 log_debug!(logger, "Updating claims view at height {} with {} claim requests", cur_height, requests.len());
713 let mut preprocessed_requests = Vec::with_capacity(requests.len());
714 let mut aggregated_request = None;
716 // Try to aggregate outputs if their timelock expiration isn't imminent (package timelock
717 // <= CLTV_SHARED_CLAIM_BUFFER) and they don't require an immediate nLockTime (aggregable).
718 for req in requests {
719 // Don't claim a outpoint twice that would be bad for privacy and may uselessly lock a CPFP input for a while
720 if let Some(_) = self.claimable_outpoints.get(req.outpoints()[0]) {
721 log_info!(logger, "Ignoring second claim for outpoint {}:{}, already registered its claiming request", req.outpoints()[0].txid, req.outpoints()[0].vout);
723 let timelocked_equivalent_package = self.locktimed_packages.iter().map(|v| v.1.iter()).flatten()
724 .find(|locked_package| locked_package.outpoints() == req.outpoints());
725 if let Some(package) = timelocked_equivalent_package {
726 log_info!(logger, "Ignoring second claim for outpoint {}:{}, we already have one which we're waiting on a timelock at {} for.",
727 req.outpoints()[0].txid, req.outpoints()[0].vout, package.package_locktime(cur_height));
731 let package_locktime = req.package_locktime(cur_height);
732 if package_locktime > cur_height + 1 {
733 log_info!(logger, "Delaying claim of package until its timelock at {} (current height {}), the following outpoints are spent:", package_locktime, cur_height);
734 for outpoint in req.outpoints() {
735 log_info!(logger, " Outpoint {}", outpoint);
737 self.locktimed_packages.entry(package_locktime).or_insert(Vec::new()).push(req);
741 log_trace!(logger, "Test if outpoint can be aggregated with expiration {} against {}", req.timelock(), cur_height + CLTV_SHARED_CLAIM_BUFFER);
742 if req.timelock() <= cur_height + CLTV_SHARED_CLAIM_BUFFER || !req.aggregable() {
743 // Don't aggregate if outpoint package timelock is soon or marked as non-aggregable
744 preprocessed_requests.push(req);
745 } else if aggregated_request.is_none() {
746 aggregated_request = Some(req);
748 aggregated_request.as_mut().unwrap().merge_package(req);
752 if let Some(req) = aggregated_request {
753 preprocessed_requests.push(req);
756 // Claim everything up to and including `cur_height`
757 let remaining_locked_packages = self.locktimed_packages.split_off(&(cur_height + 1));
758 for (pop_height, mut entry) in self.locktimed_packages.iter_mut() {
759 log_trace!(logger, "Restoring delayed claim of package(s) at their timelock at {}.", pop_height);
760 preprocessed_requests.append(&mut entry);
762 self.locktimed_packages = remaining_locked_packages;
764 // Generate claim transactions and track them to bump if necessary at
765 // height timer expiration (i.e in how many blocks we're going to take action).
766 for mut req in preprocessed_requests {
767 if let Some((new_timer, new_feerate, claim)) = self.generate_claim(
768 cur_height, &req, true /* force_feerate_bump */, &*fee_estimator, &*logger,
770 req.set_timer(new_timer);
771 req.set_feerate(new_feerate);
772 // Once a pending claim has an id assigned, it remains fixed until the claim is
773 // satisfied, regardless of whether the claim switches between different variants of
775 let claim_id = match claim {
776 OnchainClaim::Tx(tx) => {
777 log_info!(logger, "Broadcasting onchain {}", log_tx!(tx));
778 broadcaster.broadcast_transactions(&[&tx]);
779 ClaimId(tx.txid().into_inner())
781 OnchainClaim::Event(claim_event) => {
782 log_info!(logger, "Yielding onchain event to spend inputs {:?}", req.outpoints());
783 let claim_id = match claim_event {
784 ClaimEvent::BumpCommitment { ref commitment_tx, .. } =>
785 // For commitment claims, we can just use their txid as it should
786 // already be unique.
787 ClaimId(commitment_tx.txid().into_inner()),
788 ClaimEvent::BumpHTLC { ref htlcs, .. } => {
789 // For HTLC claims, commit to the entire set of HTLC outputs to
790 // claim, which will always be unique per request. Once a claim ID
791 // is generated, it is assigned and remains unchanged, even if the
792 // underlying set of HTLCs changes.
793 let mut engine = Sha256::engine();
795 engine.input(&htlc.commitment_txid.into_inner());
796 engine.input(&htlc.htlc.transaction_output_index.unwrap().to_be_bytes());
798 ClaimId(Sha256::from_engine(engine).into_inner())
801 debug_assert!(self.pending_claim_requests.get(&claim_id).is_none());
802 debug_assert_eq!(self.pending_claim_events.iter().filter(|entry| entry.0 == claim_id).count(), 0);
803 self.pending_claim_events.push((claim_id, claim_event));
807 debug_assert!(self.pending_claim_requests.get(&claim_id).is_none());
808 for k in req.outpoints() {
809 log_info!(logger, "Registering claiming request for {}:{}", k.txid, k.vout);
810 self.claimable_outpoints.insert(k.clone(), (claim_id, conf_height));
812 self.pending_claim_requests.insert(claim_id, req);
817 /// Upon channelmonitor.block_connected(..) or upon provision of a preimage on the forward link
818 /// for this channel, provide new relevant on-chain transactions and/or new claim requests.
819 /// Together with `update_claims_view_from_requests` this used to be named `block_connected`,
820 /// but it is now also used for claiming an HTLC output if we receive a preimage after force-close.
822 /// `conf_height` represents the height at which the transactions in `txn_matched` were
823 /// confirmed. This does not need to equal the current blockchain tip height, which should be
824 /// provided via `cur_height`, however it must never be higher than `cur_height`.
825 pub(crate) fn update_claims_view_from_matched_txn<B: Deref, F: Deref, L: Deref>(
826 &mut self, txn_matched: &[&Transaction], conf_height: u32, conf_hash: BlockHash,
827 cur_height: u32, broadcaster: &B, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L
829 B::Target: BroadcasterInterface,
830 F::Target: FeeEstimator,
833 log_debug!(logger, "Updating claims view at height {} with {} matched transactions in block {}", cur_height, txn_matched.len(), conf_height);
834 let mut bump_candidates = HashMap::new();
835 for tx in txn_matched {
836 // Scan all input to verify is one of the outpoint spent is of interest for us
837 let mut claimed_outputs_material = Vec::new();
838 for inp in &tx.input {
839 if let Some((claim_id, _)) = self.claimable_outpoints.get(&inp.previous_output) {
840 // If outpoint has claim request pending on it...
841 if let Some(request) = self.pending_claim_requests.get_mut(claim_id) {
842 //... we need to verify equality between transaction outpoints and claim request
843 // outpoints to know if transaction is the original claim or a bumped one issued
845 let mut are_sets_equal = true;
846 let mut tx_inputs = tx.input.iter().map(|input| &input.previous_output).collect::<Vec<_>>();
847 tx_inputs.sort_unstable();
848 for request_input in request.outpoints() {
849 if tx_inputs.binary_search(&request_input).is_err() {
850 are_sets_equal = false;
855 macro_rules! clean_claim_request_after_safety_delay {
857 let entry = OnchainEventEntry {
860 block_hash: Some(conf_hash),
861 event: OnchainEvent::Claim { claim_id: *claim_id }
863 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
864 self.onchain_events_awaiting_threshold_conf.push(entry);
869 // If this is our transaction (or our counterparty spent all the outputs
870 // before we could anyway with same inputs order than us), wait for
871 // ANTI_REORG_DELAY and clean the RBF tracking map.
873 clean_claim_request_after_safety_delay!();
874 } else { // If false, generate new claim request with update outpoint set
875 let mut at_least_one_drop = false;
876 for input in tx.input.iter() {
877 if let Some(package) = request.split_package(&input.previous_output) {
878 claimed_outputs_material.push(package);
879 at_least_one_drop = true;
881 // If there are no outpoints left to claim in this request, drop it entirely after ANTI_REORG_DELAY.
882 if request.outpoints().is_empty() {
883 clean_claim_request_after_safety_delay!();
886 //TODO: recompute soonest_timelock to avoid wasting a bit on fees
887 if at_least_one_drop {
888 bump_candidates.insert(*claim_id, request.clone());
889 // If we have any pending claim events for the request being updated
890 // that have yet to be consumed, we'll remove them since they will
891 // end up producing an invalid transaction by double spending
892 // input(s) that already have a confirmed spend. If such spend is
893 // reorged out of the chain, then we'll attempt to re-spend the
894 // inputs once we see it.
895 #[cfg(debug_assertions)] {
896 let existing = self.pending_claim_events.iter()
897 .filter(|entry| entry.0 == *claim_id).count();
898 assert!(existing == 0 || existing == 1);
900 self.pending_claim_events.retain(|entry| entry.0 != *claim_id);
903 break; //No need to iterate further, either tx is our or their
905 panic!("Inconsistencies between pending_claim_requests map and claimable_outpoints map");
909 for package in claimed_outputs_material.drain(..) {
910 let entry = OnchainEventEntry {
913 block_hash: Some(conf_hash),
914 event: OnchainEvent::ContentiousOutpoint { package },
916 if !self.onchain_events_awaiting_threshold_conf.contains(&entry) {
917 self.onchain_events_awaiting_threshold_conf.push(entry);
922 // After security delay, either our claim tx got enough confs or outpoint is definetely out of reach
923 let onchain_events_awaiting_threshold_conf =
924 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
925 for entry in onchain_events_awaiting_threshold_conf {
926 if entry.has_reached_confirmation_threshold(cur_height) {
928 OnchainEvent::Claim { claim_id } => {
929 // We may remove a whole set of claim outpoints here, as these one may have
930 // been aggregated in a single tx and claimed so atomically
931 if let Some(request) = self.pending_claim_requests.remove(&claim_id) {
932 for outpoint in request.outpoints() {
933 log_debug!(logger, "Removing claim tracking for {} due to maturation of claim package {}.",
934 outpoint, log_bytes!(claim_id.0));
935 self.claimable_outpoints.remove(outpoint);
937 #[cfg(debug_assertions)] {
938 let num_existing = self.pending_claim_events.iter()
939 .filter(|entry| entry.0 == claim_id).count();
940 assert!(num_existing == 0 || num_existing == 1);
942 self.pending_claim_events.retain(|(id, _)| *id != claim_id);
945 OnchainEvent::ContentiousOutpoint { package } => {
946 log_debug!(logger, "Removing claim tracking due to maturation of claim tx for outpoints:");
947 log_debug!(logger, " {:?}", package.outpoints());
948 self.claimable_outpoints.remove(package.outpoints()[0]);
952 self.onchain_events_awaiting_threshold_conf.push(entry);
956 // Check if any pending claim request must be rescheduled
957 for (claim_id, request) in self.pending_claim_requests.iter() {
958 if cur_height >= request.timer() {
959 bump_candidates.insert(*claim_id, request.clone());
963 // Build, bump and rebroadcast tx accordingly
964 log_trace!(logger, "Bumping {} candidates", bump_candidates.len());
965 for (claim_id, request) in bump_candidates.iter() {
966 if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(
967 cur_height, &request, true /* force_feerate_bump */, &*fee_estimator, &*logger,
970 OnchainClaim::Tx(bump_tx) => {
971 log_info!(logger, "Broadcasting RBF-bumped onchain {}", log_tx!(bump_tx));
972 broadcaster.broadcast_transactions(&[&bump_tx]);
974 OnchainClaim::Event(claim_event) => {
975 log_info!(logger, "Yielding RBF-bumped onchain event to spend inputs {:?}", request.outpoints());
976 #[cfg(debug_assertions)] {
977 let num_existing = self.pending_claim_events.iter().
978 filter(|entry| entry.0 == *claim_id).count();
979 assert!(num_existing == 0 || num_existing == 1);
981 self.pending_claim_events.retain(|event| event.0 != *claim_id);
982 self.pending_claim_events.push((*claim_id, claim_event));
985 if let Some(request) = self.pending_claim_requests.get_mut(claim_id) {
986 request.set_timer(new_timer);
987 request.set_feerate(new_feerate);
993 pub(crate) fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
997 fee_estimator: &LowerBoundedFeeEstimator<F>,
1000 B::Target: BroadcasterInterface,
1001 F::Target: FeeEstimator,
1004 let mut height = None;
1005 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
1006 if entry.txid == *txid {
1007 height = Some(entry.height);
1012 if let Some(height) = height {
1013 self.block_disconnected(height, broadcaster, fee_estimator, logger);
1017 pub(crate) fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, height: u32, broadcaster: B, fee_estimator: &LowerBoundedFeeEstimator<F>, logger: L)
1018 where B::Target: BroadcasterInterface,
1019 F::Target: FeeEstimator,
1022 let mut bump_candidates = HashMap::new();
1023 let onchain_events_awaiting_threshold_conf =
1024 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
1025 for entry in onchain_events_awaiting_threshold_conf {
1026 if entry.height >= height {
1027 //- our claim tx on a commitment tx output
1028 //- resurect outpoint back in its claimable set and regenerate tx
1030 OnchainEvent::ContentiousOutpoint { package } => {
1031 if let Some(pending_claim) = self.claimable_outpoints.get(package.outpoints()[0]) {
1032 if let Some(request) = self.pending_claim_requests.get_mut(&pending_claim.0) {
1033 request.merge_package(package);
1034 // Using a HashMap guarantee us than if we have multiple outpoints getting
1035 // resurrected only one bump claim tx is going to be broadcast
1036 bump_candidates.insert(pending_claim.clone(), request.clone());
1043 self.onchain_events_awaiting_threshold_conf.push(entry);
1046 for ((_claim_id, _), ref mut request) in bump_candidates.iter_mut() {
1047 // `height` is the height being disconnected, so our `current_height` is 1 lower.
1048 let current_height = height - 1;
1049 if let Some((new_timer, new_feerate, bump_claim)) = self.generate_claim(
1050 current_height, &request, true /* force_feerate_bump */, fee_estimator, &&*logger
1052 request.set_timer(new_timer);
1053 request.set_feerate(new_feerate);
1055 OnchainClaim::Tx(bump_tx) => {
1056 log_info!(logger, "Broadcasting onchain {}", log_tx!(bump_tx));
1057 broadcaster.broadcast_transactions(&[&bump_tx]);
1059 OnchainClaim::Event(claim_event) => {
1060 log_info!(logger, "Yielding onchain event after reorg to spend inputs {:?}", request.outpoints());
1061 #[cfg(debug_assertions)] {
1062 let num_existing = self.pending_claim_events.iter()
1063 .filter(|entry| entry.0 == *_claim_id).count();
1064 assert!(num_existing == 0 || num_existing == 1);
1066 self.pending_claim_events.retain(|event| event.0 != *_claim_id);
1067 self.pending_claim_events.push((*_claim_id, claim_event));
1072 for (ancestor_claim_txid, request) in bump_candidates.drain() {
1073 self.pending_claim_requests.insert(ancestor_claim_txid.0, request);
1075 //TODO: if we implement cross-block aggregated claim transaction we need to refresh set of outpoints and regenerate tx but
1076 // right now if one of the outpoint get disconnected, just erase whole pending claim request.
1077 let mut remove_request = Vec::new();
1078 self.claimable_outpoints.retain(|_, ref v|
1080 remove_request.push(v.0.clone());
1083 for req in remove_request {
1084 self.pending_claim_requests.remove(&req);
1088 pub(crate) fn is_output_spend_pending(&self, outpoint: &BitcoinOutPoint) -> bool {
1089 self.claimable_outpoints.get(outpoint).is_some()
1092 pub(crate) fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
1093 let mut txids: Vec<(Txid, Option<BlockHash>)> = self.onchain_events_awaiting_threshold_conf
1095 .map(|entry| (entry.txid, entry.block_hash))
1097 txids.sort_unstable_by_key(|(txid, _)| *txid);
1102 pub(crate) fn provide_latest_holder_tx(&mut self, tx: HolderCommitmentTransaction) {
1103 self.prev_holder_commitment = Some(replace(&mut self.holder_commitment, tx));
1104 self.holder_htlc_sigs = None;
1107 // Normally holder HTLCs are signed at the same time as the holder commitment tx. However,
1108 // in some configurations, the holder commitment tx has been signed and broadcast by a
1109 // ChannelMonitor replica, so we handle that case here.
1110 fn sign_latest_holder_htlcs(&mut self) {
1111 if self.holder_htlc_sigs.is_none() {
1112 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
1113 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, sigs));
1117 // Normally only the latest commitment tx and HTLCs need to be signed. However, in some
1118 // configurations we may have updated our holder commitment but a replica of the ChannelMonitor
1119 // broadcast the previous one before we sync with it. We handle that case here.
1120 fn sign_prev_holder_htlcs(&mut self) {
1121 if self.prev_holder_htlc_sigs.is_none() {
1122 if let Some(ref holder_commitment) = self.prev_holder_commitment {
1123 let (_sig, sigs) = self.signer.sign_holder_commitment_and_htlcs(holder_commitment, &self.secp_ctx).expect("sign previous holder commitment");
1124 self.prev_holder_htlc_sigs = Some(Self::extract_holder_sigs(holder_commitment, sigs));
1129 fn extract_holder_sigs(holder_commitment: &HolderCommitmentTransaction, sigs: Vec<Signature>) -> Vec<Option<(usize, Signature)>> {
1130 let mut ret = Vec::new();
1131 for (htlc_idx, (holder_sig, htlc)) in sigs.iter().zip(holder_commitment.htlcs().iter()).enumerate() {
1132 let tx_idx = htlc.transaction_output_index.unwrap();
1133 if ret.len() <= tx_idx as usize { ret.resize(tx_idx as usize + 1, None); }
1134 ret[tx_idx as usize] = Some((htlc_idx, holder_sig.clone()));
1139 pub(crate) fn get_unsigned_holder_commitment_tx(&self) -> &Transaction {
1140 &self.holder_commitment.trust().built_transaction().transaction
1143 //TODO: getting lastest holder transactions should be infallible and result in us "force-closing the channel", but we may
1144 // have empty holder commitment transaction if a ChannelMonitor is asked to force-close just after OutboundV1Channel::get_funding_created,
1145 // before providing a initial commitment transaction. For outbound channel, init ChannelMonitor at Channel::funding_signed, there is nothing
1146 // to monitor before.
1147 pub(crate) fn get_fully_signed_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
1148 let (sig, htlc_sigs) = self.signer.sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("signing holder commitment");
1149 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
1150 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
1153 #[cfg(any(test, feature="unsafe_revoked_tx_signing"))]
1154 pub(crate) fn get_fully_signed_copy_holder_tx(&mut self, funding_redeemscript: &Script) -> Transaction {
1155 let (sig, htlc_sigs) = self.signer.unsafe_sign_holder_commitment_and_htlcs(&self.holder_commitment, &self.secp_ctx).expect("sign holder commitment");
1156 self.holder_htlc_sigs = Some(Self::extract_holder_sigs(&self.holder_commitment, htlc_sigs));
1157 self.holder_commitment.add_holder_sig(funding_redeemscript, sig)
1160 pub(crate) fn get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
1161 let get_signed_htlc_tx = |holder_commitment: &HolderCommitmentTransaction| {
1162 let trusted_tx = holder_commitment.trust();
1163 if trusted_tx.txid() != outp.txid {
1166 let (htlc_idx, htlc) = trusted_tx.htlcs().iter().enumerate()
1167 .find(|(_, htlc)| htlc.transaction_output_index.unwrap() == outp.vout)
1169 let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[htlc_idx];
1170 let mut htlc_tx = trusted_tx.build_unsigned_htlc_tx(
1171 &self.channel_transaction_parameters.as_holder_broadcastable(), htlc_idx, preimage,
1174 let htlc_descriptor = HTLCDescriptor {
1175 channel_derivation_parameters: ChannelDerivationParameters {
1176 value_satoshis: self.channel_value_satoshis,
1177 keys_id: self.channel_keys_id,
1178 transaction_parameters: self.channel_transaction_parameters.clone(),
1180 commitment_txid: trusted_tx.txid(),
1181 per_commitment_number: trusted_tx.commitment_number(),
1182 per_commitment_point: trusted_tx.per_commitment_point(),
1183 feerate_per_kw: trusted_tx.feerate_per_kw(),
1185 preimage: preimage.clone(),
1186 counterparty_sig: counterparty_htlc_sig.clone(),
1188 let htlc_sig = self.signer.sign_holder_htlc_transaction(&htlc_tx, 0, &htlc_descriptor, &self.secp_ctx).unwrap();
1189 htlc_tx.input[0].witness = trusted_tx.build_htlc_input_witness(
1190 htlc_idx, &counterparty_htlc_sig, &htlc_sig, preimage,
1195 // Check if the HTLC spends from the current holder commitment first, or the previous.
1196 get_signed_htlc_tx(&self.holder_commitment)
1197 .or_else(|| self.prev_holder_commitment.as_ref().and_then(|prev_holder_commitment| get_signed_htlc_tx(prev_holder_commitment)))
1200 pub(crate) fn generate_external_htlc_claim(
1201 &self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>
1202 ) -> Option<ExternalHTLCClaim> {
1203 let find_htlc = |holder_commitment: &HolderCommitmentTransaction| -> Option<ExternalHTLCClaim> {
1204 let trusted_tx = holder_commitment.trust();
1205 if outp.txid != trusted_tx.txid() {
1208 trusted_tx.htlcs().iter().enumerate()
1209 .find(|(_, htlc)| if let Some(output_index) = htlc.transaction_output_index {
1210 output_index == outp.vout
1214 .map(|(htlc_idx, htlc)| {
1215 let counterparty_htlc_sig = holder_commitment.counterparty_htlc_sigs[htlc_idx];
1217 commitment_txid: trusted_tx.txid(),
1218 per_commitment_number: trusted_tx.commitment_number(),
1220 preimage: *preimage,
1221 counterparty_sig: counterparty_htlc_sig,
1225 // Check if the HTLC spends from the current holder commitment or the previous one otherwise.
1226 find_htlc(&self.holder_commitment)
1227 .or_else(|| self.prev_holder_commitment.as_ref().map(|c| find_htlc(c)).flatten())
1230 pub(crate) fn channel_type_features(&self) -> &ChannelTypeFeatures {
1231 &self.channel_transaction_parameters.channel_type_features
1234 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
1235 pub(crate) fn unsafe_get_fully_signed_htlc_tx(&mut self, outp: &::bitcoin::OutPoint, preimage: &Option<PaymentPreimage>) -> Option<Transaction> {
1236 let latest_had_sigs = self.holder_htlc_sigs.is_some();
1237 let prev_had_sigs = self.prev_holder_htlc_sigs.is_some();
1238 let ret = self.get_fully_signed_htlc_tx(outp, preimage);
1239 if !latest_had_sigs {
1240 self.holder_htlc_sigs = None;
1243 self.prev_holder_htlc_sigs = None;