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 monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 use bitcoin::blockdata::block::BlockHeader;
24 use bitcoin::blockdata::transaction::{OutPoint as BitcoinOutPoint, TxOut, Transaction};
25 use bitcoin::blockdata::script::Script;
27 use bitcoin::hashes::Hash;
28 use bitcoin::hashes::sha256::Hash as Sha256;
29 use bitcoin::hash_types::{Txid, BlockHash};
31 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
32 use bitcoin::secp256k1::{SecretKey, PublicKey};
33 use bitcoin::{secp256k1, EcdsaSighashType};
35 use crate::ln::channel::INITIAL_COMMITMENT_NUMBER;
36 use crate::ln::{PaymentHash, PaymentPreimage};
37 use crate::ln::msgs::DecodeError;
38 use crate::ln::chan_utils;
39 use crate::ln::chan_utils::{CommitmentTransaction, CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCClaim, ChannelTransactionParameters, HolderCommitmentTransaction, TxCreationKeys};
40 use crate::ln::channelmanager::{HTLCSource, SentHTLCId};
42 use crate::chain::{BestBlock, WatchedOutput};
43 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator, LowerBoundedFeeEstimator};
44 use crate::chain::transaction::{OutPoint, TransactionData};
45 use crate::sign::{ChannelDerivationParameters, HTLCDescriptor, SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, WriteableEcdsaChannelSigner, SignerProvider, EntropySource};
46 use crate::chain::onchaintx::{ClaimEvent, OnchainTxHandler};
47 use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
48 use crate::chain::Filter;
49 use crate::util::logger::Logger;
50 use crate::util::ser::{Readable, ReadableArgs, RequiredWrapper, MaybeReadable, UpgradableRequired, Writer, Writeable, U48};
51 use crate::util::byte_utils;
52 use crate::events::{Event, EventHandler};
53 use crate::events::bump_transaction::{AnchorDescriptor, BumpTransactionEvent};
55 use crate::prelude::*;
57 use crate::io::{self, Error};
58 use core::convert::TryInto;
60 use crate::sync::{Mutex, LockTestExt};
62 /// An update generated by the underlying channel itself which contains some new information the
63 /// [`ChannelMonitor`] should be made aware of.
65 /// Because this represents only a small number of updates to the underlying state, it is generally
66 /// much smaller than a full [`ChannelMonitor`]. However, for large single commitment transaction
67 /// updates (e.g. ones during which there are hundreds of HTLCs pending on the commitment
68 /// transaction), a single update may reach upwards of 1 MiB in serialized size.
69 #[derive(Clone, Debug, PartialEq, Eq)]
71 pub struct ChannelMonitorUpdate {
72 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
73 /// The sequence number of this update. Updates *must* be replayed in-order according to this
74 /// sequence number (and updates may panic if they are not). The update_id values are strictly
75 /// increasing and increase by one for each new update, with two exceptions specified below.
77 /// This sequence number is also used to track up to which points updates which returned
78 /// [`ChannelMonitorUpdateStatus::InProgress`] have been applied to all copies of a given
79 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
81 /// The only instances we allow where update_id values are not strictly increasing have a
82 /// special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. This update ID is used for updates that
83 /// will force close the channel by broadcasting the latest commitment transaction or
84 /// special post-force-close updates, like providing preimages necessary to claim outputs on the
85 /// broadcast commitment transaction. See its docs for more details.
87 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
91 /// The update ID used for a [`ChannelMonitorUpdate`] that is either:
93 /// (1) attempting to force close the channel by broadcasting our latest commitment transaction or
94 /// (2) providing a preimage (after the channel has been force closed) from a forward link that
95 /// allows us to spend an HTLC output on this channel's (the backward link's) broadcasted
96 /// commitment transaction.
98 /// No other [`ChannelMonitorUpdate`]s are allowed after force-close.
99 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
101 impl Writeable for ChannelMonitorUpdate {
102 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
103 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
104 self.update_id.write(w)?;
105 (self.updates.len() as u64).write(w)?;
106 for update_step in self.updates.iter() {
107 update_step.write(w)?;
109 write_tlv_fields!(w, {});
113 impl Readable for ChannelMonitorUpdate {
114 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
115 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
116 let update_id: u64 = Readable::read(r)?;
117 let len: u64 = Readable::read(r)?;
118 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
120 if let Some(upd) = MaybeReadable::read(r)? {
124 read_tlv_fields!(r, {});
125 Ok(Self { update_id, updates })
129 /// An event to be processed by the ChannelManager.
130 #[derive(Clone, PartialEq, Eq)]
131 pub enum MonitorEvent {
132 /// A monitor event containing an HTLCUpdate.
133 HTLCEvent(HTLCUpdate),
135 /// Indicates we broadcasted the channel's latest commitment transaction and thus closed the
137 HolderForceClosed(OutPoint),
139 /// Indicates a [`ChannelMonitor`] update has completed. See
140 /// [`ChannelMonitorUpdateStatus::InProgress`] for more information on how this is used.
142 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
144 /// The funding outpoint of the [`ChannelMonitor`] that was updated
145 funding_txo: OutPoint,
146 /// The Update ID from [`ChannelMonitorUpdate::update_id`] which was applied or
147 /// [`ChannelMonitor::get_latest_update_id`].
149 /// Note that this should only be set to a given update's ID if all previous updates for the
150 /// same [`ChannelMonitor`] have been applied and persisted.
151 monitor_update_id: u64,
154 impl_writeable_tlv_based_enum_upgradable!(MonitorEvent,
155 // Note that Completed is currently never serialized to disk as it is generated only in
158 (0, funding_txo, required),
159 (2, monitor_update_id, required),
163 (4, HolderForceClosed),
164 // 6 was `UpdateFailed` until LDK 0.0.117
167 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
168 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
169 /// preimage claim backward will lead to loss of funds.
170 #[derive(Clone, PartialEq, Eq)]
171 pub struct HTLCUpdate {
172 pub(crate) payment_hash: PaymentHash,
173 pub(crate) payment_preimage: Option<PaymentPreimage>,
174 pub(crate) source: HTLCSource,
175 pub(crate) htlc_value_satoshis: Option<u64>,
177 impl_writeable_tlv_based!(HTLCUpdate, {
178 (0, payment_hash, required),
179 (1, htlc_value_satoshis, option),
180 (2, source, required),
181 (4, payment_preimage, option),
184 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
185 /// instead claiming it in its own individual transaction.
186 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
187 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
188 /// HTLC-Success transaction.
189 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
190 /// transaction confirmed (and we use it in a few more, equivalent, places).
191 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
192 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
193 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
194 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
195 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
196 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
197 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
198 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
199 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
200 /// accurate block height.
201 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
202 /// with at worst this delay, so we are not only using this value as a mercy for them but also
203 /// us as a safeguard to delay with enough time.
204 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
205 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
206 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
209 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
210 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
211 /// by a [`ChannelMonitor`] may be incorrect.
212 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
213 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
214 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
215 // keep bumping another claim tx to solve the outpoint.
216 pub const ANTI_REORG_DELAY: u32 = 6;
217 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
218 /// refuse to accept a new HTLC.
220 /// This is used for a few separate purposes:
221 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
222 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
224 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
225 /// condition with the above), we will fail this HTLC without telling the user we received it,
227 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
228 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
230 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
231 /// in a race condition between the user connecting a block (which would fail it) and the user
232 /// providing us the preimage (which would claim it).
233 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
235 // TODO(devrandom) replace this with HolderCommitmentTransaction
236 #[derive(Clone, PartialEq, Eq)]
237 struct HolderSignedTx {
238 /// txid of the transaction in tx, just used to make comparison faster
240 revocation_key: PublicKey,
241 a_htlc_key: PublicKey,
242 b_htlc_key: PublicKey,
243 delayed_payment_key: PublicKey,
244 per_commitment_point: PublicKey,
245 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
246 to_self_value_sat: u64,
249 impl_writeable_tlv_based!(HolderSignedTx, {
251 // Note that this is filled in with data from OnchainTxHandler if it's missing.
252 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
253 (1, to_self_value_sat, (default_value, u64::max_value())),
254 (2, revocation_key, required),
255 (4, a_htlc_key, required),
256 (6, b_htlc_key, required),
257 (8, delayed_payment_key, required),
258 (10, per_commitment_point, required),
259 (12, feerate_per_kw, required),
260 (14, htlc_outputs, required_vec)
263 impl HolderSignedTx {
264 fn non_dust_htlcs(&self) -> Vec<HTLCOutputInCommitment> {
265 self.htlc_outputs.iter().filter_map(|(htlc, _, _)| {
266 if let Some(_) = htlc.transaction_output_index {
276 /// We use this to track static counterparty commitment transaction data and to generate any
277 /// justice or 2nd-stage preimage/timeout transactions.
278 #[derive(Clone, PartialEq, Eq)]
279 struct CounterpartyCommitmentParameters {
280 counterparty_delayed_payment_base_key: PublicKey,
281 counterparty_htlc_base_key: PublicKey,
282 on_counterparty_tx_csv: u16,
285 impl Writeable for CounterpartyCommitmentParameters {
286 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
287 w.write_all(&(0 as u64).to_be_bytes())?;
288 write_tlv_fields!(w, {
289 (0, self.counterparty_delayed_payment_base_key, required),
290 (2, self.counterparty_htlc_base_key, required),
291 (4, self.on_counterparty_tx_csv, required),
296 impl Readable for CounterpartyCommitmentParameters {
297 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
298 let counterparty_commitment_transaction = {
299 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
300 // used. Read it for compatibility.
301 let per_htlc_len: u64 = Readable::read(r)?;
302 for _ in 0..per_htlc_len {
303 let _txid: Txid = Readable::read(r)?;
304 let htlcs_count: u64 = Readable::read(r)?;
305 for _ in 0..htlcs_count {
306 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
310 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
311 let mut counterparty_htlc_base_key = RequiredWrapper(None);
312 let mut on_counterparty_tx_csv: u16 = 0;
313 read_tlv_fields!(r, {
314 (0, counterparty_delayed_payment_base_key, required),
315 (2, counterparty_htlc_base_key, required),
316 (4, on_counterparty_tx_csv, required),
318 CounterpartyCommitmentParameters {
319 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
320 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
321 on_counterparty_tx_csv,
324 Ok(counterparty_commitment_transaction)
328 /// An entry for an [`OnchainEvent`], stating the block height and hash when the event was
329 /// observed, as well as the transaction causing it.
331 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
332 #[derive(Clone, PartialEq, Eq)]
333 struct OnchainEventEntry {
336 block_hash: Option<BlockHash>, // Added as optional, will be filled in for any entry generated on 0.0.113 or after
338 transaction: Option<Transaction>, // Added as optional, but always filled in, in LDK 0.0.110
341 impl OnchainEventEntry {
342 fn confirmation_threshold(&self) -> u32 {
343 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
345 OnchainEvent::MaturingOutput {
346 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
348 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
349 // it's broadcastable when we see the previous block.
350 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
352 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
353 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
354 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
355 // it's broadcastable when we see the previous block.
356 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
363 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
364 best_block.height() >= self.confirmation_threshold()
368 /// The (output index, sats value) for the counterparty's output in a commitment transaction.
370 /// This was added as an `Option` in 0.0.110.
371 type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
373 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
374 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
375 #[derive(Clone, PartialEq, Eq)]
377 /// An outbound HTLC failing after a transaction is confirmed. Used
378 /// * when an outbound HTLC output is spent by us after the HTLC timed out
379 /// * an outbound HTLC which was not present in the commitment transaction which appeared
380 /// on-chain (either because it was not fully committed to or it was dust).
381 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
382 /// appearing only as an `HTLCSpendConfirmation`, below.
385 payment_hash: PaymentHash,
386 htlc_value_satoshis: Option<u64>,
387 /// None in the second case, above, ie when there is no relevant output in the commitment
388 /// transaction which appeared on chain.
389 commitment_tx_output_idx: Option<u32>,
391 /// An output waiting on [`ANTI_REORG_DELAY`] confirmations before we hand the user the
392 /// [`SpendableOutputDescriptor`].
394 descriptor: SpendableOutputDescriptor,
396 /// A spend of the funding output, either a commitment transaction or a cooperative closing
398 FundingSpendConfirmation {
399 /// The CSV delay for the output of the funding spend transaction (implying it is a local
400 /// commitment transaction, and this is the delay on the to_self output).
401 on_local_output_csv: Option<u16>,
402 /// If the funding spend transaction was a known remote commitment transaction, we track
403 /// the output index and amount of the counterparty's `to_self` output here.
405 /// This allows us to generate a [`Balance::CounterpartyRevokedOutputClaimable`] for the
406 /// counterparty output.
407 commitment_tx_to_counterparty_output: CommitmentTxCounterpartyOutputInfo,
409 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
410 /// is constructed. This is used when
411 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
412 /// immediately claim the HTLC on the inbound edge and track the resolution here,
413 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
414 /// * an inbound HTLC is claimed by us (with a preimage).
415 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
417 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by an
418 /// HTLC-Success/HTLC-Failure transaction (and is still claimable with a revocation
420 HTLCSpendConfirmation {
421 commitment_tx_output_idx: u32,
422 /// If the claim was made by either party with a preimage, this is filled in
423 preimage: Option<PaymentPreimage>,
424 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
425 /// we set this to the output CSV value which we will have to wait until to spend the
426 /// output (and generate a SpendableOutput event).
427 on_to_local_output_csv: Option<u16>,
431 impl Writeable for OnchainEventEntry {
432 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
433 write_tlv_fields!(writer, {
434 (0, self.txid, required),
435 (1, self.transaction, option),
436 (2, self.height, required),
437 (3, self.block_hash, option),
438 (4, self.event, required),
444 impl MaybeReadable for OnchainEventEntry {
445 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
446 let mut txid = Txid::all_zeros();
447 let mut transaction = None;
448 let mut block_hash = None;
450 let mut event = UpgradableRequired(None);
451 read_tlv_fields!(reader, {
453 (1, transaction, option),
454 (2, height, required),
455 (3, block_hash, option),
456 (4, event, upgradable_required),
458 Ok(Some(Self { txid, transaction, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
462 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
464 (0, source, required),
465 (1, htlc_value_satoshis, option),
466 (2, payment_hash, required),
467 (3, commitment_tx_output_idx, option),
469 (1, MaturingOutput) => {
470 (0, descriptor, required),
472 (3, FundingSpendConfirmation) => {
473 (0, on_local_output_csv, option),
474 (1, commitment_tx_to_counterparty_output, option),
476 (5, HTLCSpendConfirmation) => {
477 (0, commitment_tx_output_idx, required),
478 (2, preimage, option),
479 (4, on_to_local_output_csv, option),
484 #[derive(Clone, Debug, PartialEq, Eq)]
485 pub(crate) enum ChannelMonitorUpdateStep {
486 LatestHolderCommitmentTXInfo {
487 commitment_tx: HolderCommitmentTransaction,
488 /// Note that LDK after 0.0.115 supports this only containing dust HTLCs (implying the
489 /// `Signature` field is never filled in). At that point, non-dust HTLCs are implied by the
490 /// HTLC fields in `commitment_tx` and the sources passed via `nondust_htlc_sources`.
491 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
492 claimed_htlcs: Vec<(SentHTLCId, PaymentPreimage)>,
493 nondust_htlc_sources: Vec<HTLCSource>,
495 LatestCounterpartyCommitmentTXInfo {
496 commitment_txid: Txid,
497 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
498 commitment_number: u64,
499 their_per_commitment_point: PublicKey,
500 feerate_per_kw: Option<u32>,
501 to_broadcaster_value_sat: Option<u64>,
502 to_countersignatory_value_sat: Option<u64>,
505 payment_preimage: PaymentPreimage,
511 /// Used to indicate that the no future updates will occur, and likely that the latest holder
512 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
514 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
515 /// think we've fallen behind!
516 should_broadcast: bool,
519 scriptpubkey: Script,
523 impl ChannelMonitorUpdateStep {
524 fn variant_name(&self) -> &'static str {
526 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { .. } => "LatestHolderCommitmentTXInfo",
527 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } => "LatestCounterpartyCommitmentTXInfo",
528 ChannelMonitorUpdateStep::PaymentPreimage { .. } => "PaymentPreimage",
529 ChannelMonitorUpdateStep::CommitmentSecret { .. } => "CommitmentSecret",
530 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => "ChannelForceClosed",
531 ChannelMonitorUpdateStep::ShutdownScript { .. } => "ShutdownScript",
536 impl_writeable_tlv_based_enum_upgradable!(ChannelMonitorUpdateStep,
537 (0, LatestHolderCommitmentTXInfo) => {
538 (0, commitment_tx, required),
539 (1, claimed_htlcs, optional_vec),
540 (2, htlc_outputs, required_vec),
541 (4, nondust_htlc_sources, optional_vec),
543 (1, LatestCounterpartyCommitmentTXInfo) => {
544 (0, commitment_txid, required),
545 (1, feerate_per_kw, option),
546 (2, commitment_number, required),
547 (3, to_broadcaster_value_sat, option),
548 (4, their_per_commitment_point, required),
549 (5, to_countersignatory_value_sat, option),
550 (6, htlc_outputs, required_vec),
552 (2, PaymentPreimage) => {
553 (0, payment_preimage, required),
555 (3, CommitmentSecret) => {
557 (2, secret, required),
559 (4, ChannelForceClosed) => {
560 (0, should_broadcast, required),
562 (5, ShutdownScript) => {
563 (0, scriptpubkey, required),
567 /// Details about the balance(s) available for spending once the channel appears on chain.
569 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
571 #[derive(Clone, Debug, PartialEq, Eq)]
572 #[cfg_attr(test, derive(PartialOrd, Ord))]
574 /// The channel is not yet closed (or the commitment or closing transaction has not yet
575 /// appeared in a block). The given balance is claimable (less on-chain fees) if the channel is
576 /// force-closed now.
577 ClaimableOnChannelClose {
578 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
579 /// required to do so.
580 amount_satoshis: u64,
581 /// The transaction fee we pay for the closing commitment transaction. This amount is not
582 /// included in the [`Balance::ClaimableOnChannelClose::amount_satoshis`] value.
584 /// Note that if this channel is inbound (and thus our counterparty pays the commitment
585 /// transaction fee) this value will be zero. For [`ChannelMonitor`]s created prior to LDK
586 /// 0.0.117, the channel is always treated as outbound (and thus this value is never zero).
587 transaction_fee_satoshis: u64,
588 /// The amount of millisatoshis which has been burned to fees from HTLCs which are outbound
589 /// from us and are related to a payment which was sent by us. This is the sum of the
590 /// millisatoshis part of all HTLCs which are otherwise represented by
591 /// [`Balance::MaybeTimeoutClaimableHTLC`] with their
592 /// [`Balance::MaybeTimeoutClaimableHTLC::outbound_payment`] flag set, as well as any dust
593 /// HTLCs which would otherwise be represented the same.
594 outbound_payment_htlc_rounded_msat: u64,
595 /// The amount of millisatoshis which has been burned to fees from HTLCs which are outbound
596 /// from us and are related to a forwarded HTLC. This is the sum of the millisatoshis part
597 /// of all HTLCs which are otherwise represented by [`Balance::MaybeTimeoutClaimableHTLC`]
598 /// with their [`Balance::MaybeTimeoutClaimableHTLC::outbound_payment`] flag *not* set, as
599 /// well as any dust HTLCs which would otherwise be represented the same.
600 outbound_forwarded_htlc_rounded_msat: u64,
601 /// The amount of millisatoshis which has been burned to fees from HTLCs which are inbound
602 /// to us and for which we know the preimage. This is the sum of the millisatoshis part of
603 /// all HTLCs which would be represented by [`Balance::ContentiousClaimable`] on channel
604 /// close, but who's current value is included in
605 /// [`Balance::ClaimableOnChannelClose::amount_satoshis`], as well as any dust HTLCs which
606 /// would otherwise be represented the same.
607 inbound_claiming_htlc_rounded_msat: u64,
608 /// The amount of millisatoshis which has been burned to fees from HTLCs which are inbound
609 /// to us and for which we do not know the preimage. This is the sum of the millisatoshis
610 /// part of all HTLCs which would be represented by [`Balance::MaybePreimageClaimableHTLC`]
611 /// on channel close, as well as any dust HTLCs which would otherwise be represented the
613 inbound_htlc_rounded_msat: u64,
615 /// The channel has been closed, and the given balance is ours but awaiting confirmations until
616 /// we consider it spendable.
617 ClaimableAwaitingConfirmations {
618 /// The amount available to claim, in satoshis, possibly excluding the on-chain fees which
619 /// were spent in broadcasting the transaction.
620 amount_satoshis: u64,
621 /// The height at which an [`Event::SpendableOutputs`] event will be generated for this
623 confirmation_height: u32,
625 /// The channel has been closed, and the given balance should be ours but awaiting spending
626 /// transaction confirmation. If the spending transaction does not confirm in time, it is
627 /// possible our counterparty can take the funds by broadcasting an HTLC timeout on-chain.
629 /// Once the spending transaction confirms, before it has reached enough confirmations to be
630 /// considered safe from chain reorganizations, the balance will instead be provided via
631 /// [`Balance::ClaimableAwaitingConfirmations`].
632 ContentiousClaimable {
633 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
634 /// required to do so.
635 amount_satoshis: u64,
636 /// The height at which the counterparty may be able to claim the balance if we have not
639 /// The payment hash that locks this HTLC.
640 payment_hash: PaymentHash,
641 /// The preimage that can be used to claim this HTLC.
642 payment_preimage: PaymentPreimage,
644 /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
645 /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
646 /// likely to be claimed by our counterparty before we do.
647 MaybeTimeoutClaimableHTLC {
648 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
649 /// which will be required to do so.
650 amount_satoshis: u64,
651 /// The height at which we will be able to claim the balance if our counterparty has not
653 claimable_height: u32,
654 /// The payment hash whose preimage our counterparty needs to claim this HTLC.
655 payment_hash: PaymentHash,
656 /// Whether this HTLC represents a payment which was sent outbound from us. Otherwise it
657 /// represents an HTLC which was forwarded (and should, thus, have a corresponding inbound
658 /// edge on another channel).
659 outbound_payment: bool,
661 /// HTLCs which we received from our counterparty which are claimable with a preimage which we
662 /// do not currently have. This will only be claimable if we receive the preimage from the node
663 /// to which we forwarded this HTLC before the timeout.
664 MaybePreimageClaimableHTLC {
665 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
666 /// which will be required to do so.
667 amount_satoshis: u64,
668 /// The height at which our counterparty will be able to claim the balance if we have not
669 /// yet received the preimage and claimed it ourselves.
671 /// The payment hash whose preimage we need to claim this HTLC.
672 payment_hash: PaymentHash,
674 /// The channel has been closed, and our counterparty broadcasted a revoked commitment
677 /// Thus, we're able to claim all outputs in the commitment transaction, one of which has the
678 /// following amount.
679 CounterpartyRevokedOutputClaimable {
680 /// The amount, in satoshis, of the output which we can claim.
682 /// Note that for outputs from HTLC balances this may be excluding some on-chain fees that
683 /// were already spent.
684 amount_satoshis: u64,
689 /// The amount claimable, in satoshis. This excludes balances that we are unsure if we are able
690 /// to claim, this is because we are waiting for a preimage or for a timeout to expire. For more
691 /// information on these balances see [`Balance::MaybeTimeoutClaimableHTLC`] and
692 /// [`Balance::MaybePreimageClaimableHTLC`].
694 /// On-chain fees required to claim the balance are not included in this amount.
695 pub fn claimable_amount_satoshis(&self) -> u64 {
697 Balance::ClaimableOnChannelClose { amount_satoshis, .. }|
698 Balance::ClaimableAwaitingConfirmations { amount_satoshis, .. }|
699 Balance::ContentiousClaimable { amount_satoshis, .. }|
700 Balance::CounterpartyRevokedOutputClaimable { amount_satoshis, .. }
702 Balance::MaybeTimeoutClaimableHTLC { amount_satoshis, outbound_payment, .. }
703 => if *outbound_payment { 0 } else { *amount_satoshis },
704 Balance::MaybePreimageClaimableHTLC { .. } => 0,
709 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
710 #[derive(Clone, PartialEq, Eq)]
711 struct IrrevocablyResolvedHTLC {
712 commitment_tx_output_idx: Option<u32>,
713 /// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
714 /// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
716 resolving_txid: Option<Txid>, // Added as optional, but always filled in, in 0.0.110
717 resolving_tx: Option<Transaction>,
718 /// Only set if the HTLC claim was ours using a payment preimage
719 payment_preimage: Option<PaymentPreimage>,
722 // In LDK versions prior to 0.0.111 commitment_tx_output_idx was not Option-al and
723 // IrrevocablyResolvedHTLC objects only existed for non-dust HTLCs. This was a bug, but to maintain
724 // backwards compatibility we must ensure we always write out a commitment_tx_output_idx field,
725 // using `u32::max_value()` as a sentinal to indicate the HTLC was dust.
726 impl Writeable for IrrevocablyResolvedHTLC {
727 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
728 let mapped_commitment_tx_output_idx = self.commitment_tx_output_idx.unwrap_or(u32::max_value());
729 write_tlv_fields!(writer, {
730 (0, mapped_commitment_tx_output_idx, required),
731 (1, self.resolving_txid, option),
732 (2, self.payment_preimage, option),
733 (3, self.resolving_tx, option),
739 impl Readable for IrrevocablyResolvedHTLC {
740 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
741 let mut mapped_commitment_tx_output_idx = 0;
742 let mut resolving_txid = None;
743 let mut payment_preimage = None;
744 let mut resolving_tx = None;
745 read_tlv_fields!(reader, {
746 (0, mapped_commitment_tx_output_idx, required),
747 (1, resolving_txid, option),
748 (2, payment_preimage, option),
749 (3, resolving_tx, option),
752 commitment_tx_output_idx: if mapped_commitment_tx_output_idx == u32::max_value() { None } else { Some(mapped_commitment_tx_output_idx) },
760 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
761 /// on-chain transactions to ensure no loss of funds occurs.
763 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
764 /// information and are actively monitoring the chain.
766 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
767 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
768 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
769 /// returned block hash and the the current chain and then reconnecting blocks to get to the
770 /// best chain) upon deserializing the object!
771 pub struct ChannelMonitor<Signer: WriteableEcdsaChannelSigner> {
773 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
775 pub(super) inner: Mutex<ChannelMonitorImpl<Signer>>,
778 impl<Signer: WriteableEcdsaChannelSigner> Clone for ChannelMonitor<Signer> where Signer: Clone {
779 fn clone(&self) -> Self {
780 let inner = self.inner.lock().unwrap().clone();
781 ChannelMonitor::from_impl(inner)
785 #[derive(Clone, PartialEq)]
786 pub(crate) struct ChannelMonitorImpl<Signer: WriteableEcdsaChannelSigner> {
787 latest_update_id: u64,
788 commitment_transaction_number_obscure_factor: u64,
790 destination_script: Script,
791 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
792 counterparty_payment_script: Script,
793 shutdown_script: Option<Script>,
795 channel_keys_id: [u8; 32],
796 holder_revocation_basepoint: PublicKey,
797 funding_info: (OutPoint, Script),
798 current_counterparty_commitment_txid: Option<Txid>,
799 prev_counterparty_commitment_txid: Option<Txid>,
801 counterparty_commitment_params: CounterpartyCommitmentParameters,
802 funding_redeemscript: Script,
803 channel_value_satoshis: u64,
804 // first is the idx of the first of the two per-commitment points
805 their_cur_per_commitment_points: Option<(u64, PublicKey, Option<PublicKey>)>,
807 on_holder_tx_csv: u16,
809 commitment_secrets: CounterpartyCommitmentSecrets,
810 /// The set of outpoints in each counterparty commitment transaction. We always need at least
811 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
812 /// transaction broadcast as we need to be able to construct the witness script in all cases.
813 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
814 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
815 /// Nor can we figure out their commitment numbers without the commitment transaction they are
816 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
817 /// commitment transactions which we find on-chain, mapping them to the commitment number which
818 /// can be used to derive the revocation key and claim the transactions.
819 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
820 /// Cache used to make pruning of payment_preimages faster.
821 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
822 /// counterparty transactions (ie should remain pretty small).
823 /// Serialized to disk but should generally not be sent to Watchtowers.
824 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
826 counterparty_fulfilled_htlcs: HashMap<SentHTLCId, PaymentPreimage>,
828 // We store two holder commitment transactions to avoid any race conditions where we may update
829 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
830 // various monitors for one channel being out of sync, and us broadcasting a holder
831 // transaction for which we have deleted claim information on some watchtowers.
832 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
833 current_holder_commitment_tx: HolderSignedTx,
835 // Used just for ChannelManager to make sure it has the latest channel data during
837 current_counterparty_commitment_number: u64,
838 // Used just for ChannelManager to make sure it has the latest channel data during
840 current_holder_commitment_number: u64,
842 /// The set of payment hashes from inbound payments for which we know the preimage. Payment
843 /// preimages that are not included in any unrevoked local commitment transaction or unrevoked
844 /// remote commitment transactions are automatically removed when commitment transactions are
846 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
848 // Note that `MonitorEvent`s MUST NOT be generated during update processing, only generated
849 // during chain data processing. This prevents a race in `ChainMonitor::update_channel` (and
850 // presumably user implementations thereof as well) where we update the in-memory channel
851 // object, then before the persistence finishes (as it's all under a read-lock), we return
852 // pending events to the user or to the relevant `ChannelManager`. Then, on reload, we'll have
853 // the pre-event state here, but have processed the event in the `ChannelManager`.
854 // Note that because the `event_lock` in `ChainMonitor` is only taken in
855 // block/transaction-connected events and *not* during block/transaction-disconnected events,
856 // we further MUST NOT generate events during block/transaction-disconnection.
857 pending_monitor_events: Vec<MonitorEvent>,
859 pub(super) pending_events: Vec<Event>,
860 pub(super) is_processing_pending_events: bool,
862 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
863 // which to take actions once they reach enough confirmations. Each entry includes the
864 // transaction's id and the height when the transaction was confirmed on chain.
865 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
867 // If we get serialized out and re-read, we need to make sure that the chain monitoring
868 // interface knows about the TXOs that we want to be notified of spends of. We could probably
869 // be smart and derive them from the above storage fields, but its much simpler and more
870 // Obviously Correct (tm) if we just keep track of them explicitly.
871 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
874 pub onchain_tx_handler: OnchainTxHandler<Signer>,
876 onchain_tx_handler: OnchainTxHandler<Signer>,
878 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
879 // channel has been force-closed. After this is set, no further holder commitment transaction
880 // updates may occur, and we panic!() if one is provided.
881 lockdown_from_offchain: bool,
883 // Set once we've signed a holder commitment transaction and handed it over to our
884 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
885 // may occur, and we fail any such monitor updates.
887 // In case of update rejection due to a locally already signed commitment transaction, we
888 // nevertheless store update content to track in case of concurrent broadcast by another
889 // remote monitor out-of-order with regards to the block view.
890 holder_tx_signed: bool,
892 // If a spend of the funding output is seen, we set this to true and reject any further
893 // updates. This prevents any further changes in the offchain state no matter the order
894 // of block connection between ChannelMonitors and the ChannelManager.
895 funding_spend_seen: bool,
897 /// True if the commitment transaction fee is paid by us.
898 /// Added in 0.0.117.
899 holder_pays_commitment_tx_fee: Option<bool>,
901 /// Set to `Some` of the confirmed transaction spending the funding input of the channel after
902 /// reaching `ANTI_REORG_DELAY` confirmations.
903 funding_spend_confirmed: Option<Txid>,
905 confirmed_commitment_tx_counterparty_output: CommitmentTxCounterpartyOutputInfo,
906 /// The set of HTLCs which have been either claimed or failed on chain and have reached
907 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
908 /// spending CSV for revocable outputs).
909 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
911 /// The set of `SpendableOutput` events which we have already passed upstream to be claimed.
912 /// These are tracked explicitly to ensure that we don't generate the same events redundantly
913 /// if users duplicatively confirm old transactions. Specifically for transactions claiming a
914 /// revoked remote outpoint we otherwise have no tracking at all once they've reached
915 /// [`ANTI_REORG_DELAY`], so we have to track them here.
916 spendable_txids_confirmed: Vec<Txid>,
918 // We simply modify best_block in Channel's block_connected so that serialization is
919 // consistent but hopefully the users' copy handles block_connected in a consistent way.
920 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
921 // their best_block from its state and not based on updated copies that didn't run through
922 // the full block_connected).
923 best_block: BestBlock,
925 /// The node_id of our counterparty
926 counterparty_node_id: Option<PublicKey>,
928 /// Initial counterparty commmitment data needed to recreate the commitment tx
929 /// in the persistence pipeline for third-party watchtowers. This will only be present on
930 /// monitors created after 0.0.117.
932 /// Ordering of tuple data: (their_per_commitment_point, feerate_per_kw, to_broadcaster_sats,
933 /// to_countersignatory_sats)
934 initial_counterparty_commitment_info: Option<(PublicKey, u32, u64, u64)>,
937 /// Transaction outputs to watch for on-chain spends.
938 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
940 impl<Signer: WriteableEcdsaChannelSigner> PartialEq for ChannelMonitor<Signer> where Signer: PartialEq {
941 fn eq(&self, other: &Self) -> bool {
942 // We need some kind of total lockorder. Absent a better idea, we sort by position in
943 // memory and take locks in that order (assuming that we can't move within memory while a
945 let ord = ((self as *const _) as usize) < ((other as *const _) as usize);
946 let a = if ord { self.inner.unsafe_well_ordered_double_lock_self() } else { other.inner.unsafe_well_ordered_double_lock_self() };
947 let b = if ord { other.inner.unsafe_well_ordered_double_lock_self() } else { self.inner.unsafe_well_ordered_double_lock_self() };
952 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitor<Signer> {
953 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
954 self.inner.lock().unwrap().write(writer)
958 // These are also used for ChannelMonitorUpdate, above.
959 const SERIALIZATION_VERSION: u8 = 1;
960 const MIN_SERIALIZATION_VERSION: u8 = 1;
962 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitorImpl<Signer> {
963 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
964 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
966 self.latest_update_id.write(writer)?;
968 // Set in initial Channel-object creation, so should always be set by now:
969 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
971 self.destination_script.write(writer)?;
972 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
973 writer.write_all(&[0; 1])?;
974 broadcasted_holder_revokable_script.0.write(writer)?;
975 broadcasted_holder_revokable_script.1.write(writer)?;
976 broadcasted_holder_revokable_script.2.write(writer)?;
978 writer.write_all(&[1; 1])?;
981 self.counterparty_payment_script.write(writer)?;
982 match &self.shutdown_script {
983 Some(script) => script.write(writer)?,
984 None => Script::new().write(writer)?,
987 self.channel_keys_id.write(writer)?;
988 self.holder_revocation_basepoint.write(writer)?;
989 writer.write_all(&self.funding_info.0.txid[..])?;
990 writer.write_all(&self.funding_info.0.index.to_be_bytes())?;
991 self.funding_info.1.write(writer)?;
992 self.current_counterparty_commitment_txid.write(writer)?;
993 self.prev_counterparty_commitment_txid.write(writer)?;
995 self.counterparty_commitment_params.write(writer)?;
996 self.funding_redeemscript.write(writer)?;
997 self.channel_value_satoshis.write(writer)?;
999 match self.their_cur_per_commitment_points {
1000 Some((idx, pubkey, second_option)) => {
1001 writer.write_all(&byte_utils::be48_to_array(idx))?;
1002 writer.write_all(&pubkey.serialize())?;
1003 match second_option {
1004 Some(second_pubkey) => {
1005 writer.write_all(&second_pubkey.serialize())?;
1008 writer.write_all(&[0; 33])?;
1013 writer.write_all(&byte_utils::be48_to_array(0))?;
1017 writer.write_all(&self.on_holder_tx_csv.to_be_bytes())?;
1019 self.commitment_secrets.write(writer)?;
1021 macro_rules! serialize_htlc_in_commitment {
1022 ($htlc_output: expr) => {
1023 writer.write_all(&[$htlc_output.offered as u8; 1])?;
1024 writer.write_all(&$htlc_output.amount_msat.to_be_bytes())?;
1025 writer.write_all(&$htlc_output.cltv_expiry.to_be_bytes())?;
1026 writer.write_all(&$htlc_output.payment_hash.0[..])?;
1027 $htlc_output.transaction_output_index.write(writer)?;
1031 writer.write_all(&(self.counterparty_claimable_outpoints.len() as u64).to_be_bytes())?;
1032 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
1033 writer.write_all(&txid[..])?;
1034 writer.write_all(&(htlc_infos.len() as u64).to_be_bytes())?;
1035 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
1036 debug_assert!(htlc_source.is_none() || Some(**txid) == self.current_counterparty_commitment_txid
1037 || Some(**txid) == self.prev_counterparty_commitment_txid,
1038 "HTLC Sources for all revoked commitment transactions should be none!");
1039 serialize_htlc_in_commitment!(htlc_output);
1040 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1044 writer.write_all(&(self.counterparty_commitment_txn_on_chain.len() as u64).to_be_bytes())?;
1045 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
1046 writer.write_all(&txid[..])?;
1047 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1050 writer.write_all(&(self.counterparty_hash_commitment_number.len() as u64).to_be_bytes())?;
1051 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
1052 writer.write_all(&payment_hash.0[..])?;
1053 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1056 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
1057 writer.write_all(&[1; 1])?;
1058 prev_holder_tx.write(writer)?;
1060 writer.write_all(&[0; 1])?;
1063 self.current_holder_commitment_tx.write(writer)?;
1065 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
1066 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
1068 writer.write_all(&(self.payment_preimages.len() as u64).to_be_bytes())?;
1069 for payment_preimage in self.payment_preimages.values() {
1070 writer.write_all(&payment_preimage.0[..])?;
1073 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
1074 MonitorEvent::HTLCEvent(_) => true,
1075 MonitorEvent::HolderForceClosed(_) => true,
1077 }).count() as u64).to_be_bytes())?;
1078 for event in self.pending_monitor_events.iter() {
1080 MonitorEvent::HTLCEvent(upd) => {
1084 MonitorEvent::HolderForceClosed(_) => 1u8.write(writer)?,
1085 _ => {}, // Covered in the TLV writes below
1089 writer.write_all(&(self.pending_events.len() as u64).to_be_bytes())?;
1090 for event in self.pending_events.iter() {
1091 event.write(writer)?;
1094 self.best_block.block_hash().write(writer)?;
1095 writer.write_all(&self.best_block.height().to_be_bytes())?;
1097 writer.write_all(&(self.onchain_events_awaiting_threshold_conf.len() as u64).to_be_bytes())?;
1098 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
1099 entry.write(writer)?;
1102 (self.outputs_to_watch.len() as u64).write(writer)?;
1103 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
1104 txid.write(writer)?;
1105 (idx_scripts.len() as u64).write(writer)?;
1106 for (idx, script) in idx_scripts.iter() {
1108 script.write(writer)?;
1111 self.onchain_tx_handler.write(writer)?;
1113 self.lockdown_from_offchain.write(writer)?;
1114 self.holder_tx_signed.write(writer)?;
1116 write_tlv_fields!(writer, {
1117 (1, self.funding_spend_confirmed, option),
1118 (3, self.htlcs_resolved_on_chain, required_vec),
1119 (5, self.pending_monitor_events, required_vec),
1120 (7, self.funding_spend_seen, required),
1121 (9, self.counterparty_node_id, option),
1122 (11, self.confirmed_commitment_tx_counterparty_output, option),
1123 (13, self.spendable_txids_confirmed, required_vec),
1124 (15, self.counterparty_fulfilled_htlcs, required),
1125 (17, self.initial_counterparty_commitment_info, option),
1126 (19, self.holder_pays_commitment_tx_fee, option),
1133 macro_rules! _process_events_body {
1134 ($self_opt: expr, $event_to_handle: expr, $handle_event: expr) => {
1136 let (pending_events, repeated_events);
1137 if let Some(us) = $self_opt {
1138 let mut inner = us.inner.lock().unwrap();
1139 if inner.is_processing_pending_events {
1142 inner.is_processing_pending_events = true;
1144 pending_events = inner.pending_events.clone();
1145 repeated_events = inner.get_repeated_events();
1147 let num_events = pending_events.len();
1149 for event in pending_events.into_iter().chain(repeated_events.into_iter()) {
1150 $event_to_handle = event;
1154 if let Some(us) = $self_opt {
1155 let mut inner = us.inner.lock().unwrap();
1156 inner.pending_events.drain(..num_events);
1157 inner.is_processing_pending_events = false;
1158 if !inner.pending_events.is_empty() {
1159 // If there's more events to process, go ahead and do so.
1167 pub(super) use _process_events_body as process_events_body;
1169 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1170 /// For lockorder enforcement purposes, we need to have a single site which constructs the
1171 /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
1172 /// PartialEq implementation) we may decide a lockorder violation has occurred.
1173 fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
1174 ChannelMonitor { inner: Mutex::new(imp) }
1177 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
1178 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1179 channel_parameters: &ChannelTransactionParameters, holder_pays_commitment_tx_fee: bool,
1180 funding_redeemscript: Script, channel_value_satoshis: u64,
1181 commitment_transaction_number_obscure_factor: u64,
1182 initial_holder_commitment_tx: HolderCommitmentTransaction,
1183 best_block: BestBlock, counterparty_node_id: PublicKey) -> ChannelMonitor<Signer> {
1185 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1186 let counterparty_payment_script = chan_utils::get_counterparty_payment_script(
1187 &channel_parameters.channel_type_features, &keys.pubkeys().payment_point
1190 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
1191 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
1192 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
1193 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
1195 let channel_keys_id = keys.channel_keys_id();
1196 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1198 // block for Rust 1.34 compat
1199 let (holder_commitment_tx, current_holder_commitment_number) = {
1200 let trusted_tx = initial_holder_commitment_tx.trust();
1201 let txid = trusted_tx.txid();
1203 let tx_keys = trusted_tx.keys();
1204 let holder_commitment_tx = HolderSignedTx {
1206 revocation_key: tx_keys.revocation_key,
1207 a_htlc_key: tx_keys.broadcaster_htlc_key,
1208 b_htlc_key: tx_keys.countersignatory_htlc_key,
1209 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1210 per_commitment_point: tx_keys.per_commitment_point,
1211 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1212 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
1213 feerate_per_kw: trusted_tx.feerate_per_kw(),
1215 (holder_commitment_tx, trusted_tx.commitment_number())
1218 let onchain_tx_handler = OnchainTxHandler::new(
1219 channel_value_satoshis, channel_keys_id, destination_script.clone(), keys,
1220 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx
1223 let mut outputs_to_watch = HashMap::new();
1224 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1226 Self::from_impl(ChannelMonitorImpl {
1227 latest_update_id: 0,
1228 commitment_transaction_number_obscure_factor,
1230 destination_script: destination_script.clone(),
1231 broadcasted_holder_revokable_script: None,
1232 counterparty_payment_script,
1236 holder_revocation_basepoint,
1238 current_counterparty_commitment_txid: None,
1239 prev_counterparty_commitment_txid: None,
1241 counterparty_commitment_params,
1242 funding_redeemscript,
1243 channel_value_satoshis,
1244 their_cur_per_commitment_points: None,
1246 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1248 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1249 counterparty_claimable_outpoints: HashMap::new(),
1250 counterparty_commitment_txn_on_chain: HashMap::new(),
1251 counterparty_hash_commitment_number: HashMap::new(),
1252 counterparty_fulfilled_htlcs: HashMap::new(),
1254 prev_holder_signed_commitment_tx: None,
1255 current_holder_commitment_tx: holder_commitment_tx,
1256 current_counterparty_commitment_number: 1 << 48,
1257 current_holder_commitment_number,
1259 payment_preimages: HashMap::new(),
1260 pending_monitor_events: Vec::new(),
1261 pending_events: Vec::new(),
1262 is_processing_pending_events: false,
1264 onchain_events_awaiting_threshold_conf: Vec::new(),
1269 holder_pays_commitment_tx_fee: Some(holder_pays_commitment_tx_fee),
1270 lockdown_from_offchain: false,
1271 holder_tx_signed: false,
1272 funding_spend_seen: false,
1273 funding_spend_confirmed: None,
1274 confirmed_commitment_tx_counterparty_output: None,
1275 htlcs_resolved_on_chain: Vec::new(),
1276 spendable_txids_confirmed: Vec::new(),
1279 counterparty_node_id: Some(counterparty_node_id),
1280 initial_counterparty_commitment_info: None,
1285 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1286 self.inner.lock().unwrap().provide_secret(idx, secret)
1289 /// A variant of `Self::provide_latest_counterparty_commitment_tx` used to provide
1290 /// additional information to the monitor to store in order to recreate the initial
1291 /// counterparty commitment transaction during persistence (mainly for use in third-party
1294 /// This is used to provide the counterparty commitment information directly to the monitor
1295 /// before the initial persistence of a new channel.
1296 pub(crate) fn provide_initial_counterparty_commitment_tx<L: Deref>(
1297 &self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1298 commitment_number: u64, their_cur_per_commitment_point: PublicKey, feerate_per_kw: u32,
1299 to_broadcaster_value_sat: u64, to_countersignatory_value_sat: u64, logger: &L,
1301 where L::Target: Logger
1303 self.inner.lock().unwrap().provide_initial_counterparty_commitment_tx(txid,
1304 htlc_outputs, commitment_number, their_cur_per_commitment_point, feerate_per_kw,
1305 to_broadcaster_value_sat, to_countersignatory_value_sat, logger);
1308 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1309 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1310 /// possibly future revocation/preimage information) to claim outputs where possible.
1311 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1313 fn provide_latest_counterparty_commitment_tx<L: Deref>(
1316 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1317 commitment_number: u64,
1318 their_per_commitment_point: PublicKey,
1320 ) where L::Target: Logger {
1321 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1322 txid, htlc_outputs, commitment_number, their_per_commitment_point, logger)
1326 fn provide_latest_holder_commitment_tx(
1327 &self, holder_commitment_tx: HolderCommitmentTransaction,
1328 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1329 ) -> Result<(), ()> {
1330 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(holder_commitment_tx, htlc_outputs, &Vec::new(), Vec::new()).map_err(|_| ())
1333 /// This is used to provide payment preimage(s) out-of-band during startup without updating the
1334 /// off-chain state with a new commitment transaction.
1335 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1337 payment_hash: &PaymentHash,
1338 payment_preimage: &PaymentPreimage,
1340 fee_estimator: &LowerBoundedFeeEstimator<F>,
1343 B::Target: BroadcasterInterface,
1344 F::Target: FeeEstimator,
1347 self.inner.lock().unwrap().provide_payment_preimage(
1348 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1351 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1354 /// panics if the given update is not the next update by update_id.
1355 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1357 updates: &ChannelMonitorUpdate,
1363 B::Target: BroadcasterInterface,
1364 F::Target: FeeEstimator,
1367 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1370 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1372 pub fn get_latest_update_id(&self) -> u64 {
1373 self.inner.lock().unwrap().get_latest_update_id()
1376 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1377 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1378 self.inner.lock().unwrap().get_funding_txo().clone()
1381 /// Gets a list of txids, with their output scripts (in the order they appear in the
1382 /// transaction), which we must learn about spends of via block_connected().
1383 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1384 self.inner.lock().unwrap().get_outputs_to_watch()
1385 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1388 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1389 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1390 /// have been registered.
1391 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1392 let lock = self.inner.lock().unwrap();
1393 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1394 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1395 for (index, script_pubkey) in outputs.iter() {
1396 assert!(*index <= u16::max_value() as u32);
1397 filter.register_output(WatchedOutput {
1399 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1400 script_pubkey: script_pubkey.clone(),
1406 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1407 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1408 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1409 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1412 /// Processes [`SpendableOutputs`] events produced from each [`ChannelMonitor`] upon maturity.
1414 /// For channels featuring anchor outputs, this method will also process [`BumpTransaction`]
1415 /// events produced from each [`ChannelMonitor`] while there is a balance to claim onchain
1416 /// within each channel. As the confirmation of a commitment transaction may be critical to the
1417 /// safety of funds, we recommend invoking this every 30 seconds, or lower if running in an
1418 /// environment with spotty connections, like on mobile.
1420 /// An [`EventHandler`] may safely call back to the provider, though this shouldn't be needed in
1421 /// order to handle these events.
1423 /// [`SpendableOutputs`]: crate::events::Event::SpendableOutputs
1424 /// [`BumpTransaction`]: crate::events::Event::BumpTransaction
1425 pub fn process_pending_events<H: Deref>(&self, handler: &H) where H::Target: EventHandler {
1427 process_events_body!(Some(self), ev, handler.handle_event(ev));
1430 /// Processes any events asynchronously.
1432 /// See [`Self::process_pending_events`] for more information.
1433 pub async fn process_pending_events_async<Future: core::future::Future, H: Fn(Event) -> Future>(
1437 process_events_body!(Some(self), ev, { handler(ev).await });
1441 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1442 let mut ret = Vec::new();
1443 let mut lck = self.inner.lock().unwrap();
1444 mem::swap(&mut ret, &mut lck.pending_events);
1445 ret.append(&mut lck.get_repeated_events());
1449 /// Gets the counterparty's initial commitment transaction. The returned commitment
1450 /// transaction is unsigned. This is intended to be called during the initial persistence of
1451 /// the monitor (inside an implementation of [`Persist::persist_new_channel`]), to allow for
1452 /// watchtowers in the persistence pipeline to have enough data to form justice transactions.
1454 /// This is similar to [`Self::counterparty_commitment_txs_from_update`], except
1455 /// that for the initial commitment transaction, we don't have a corresponding update.
1457 /// This will only return `Some` for channel monitors that have been created after upgrading
1458 /// to LDK 0.0.117+.
1460 /// [`Persist::persist_new_channel`]: crate::chain::chainmonitor::Persist::persist_new_channel
1461 pub fn initial_counterparty_commitment_tx(&self) -> Option<CommitmentTransaction> {
1462 self.inner.lock().unwrap().initial_counterparty_commitment_tx()
1465 /// Gets all of the counterparty commitment transactions provided by the given update. This
1466 /// may be empty if the update doesn't include any new counterparty commitments. Returned
1467 /// commitment transactions are unsigned.
1469 /// This is provided so that watchtower clients in the persistence pipeline are able to build
1470 /// justice transactions for each counterparty commitment upon each update. It's intended to be
1471 /// used within an implementation of [`Persist::update_persisted_channel`], which is provided
1472 /// with a monitor and an update. Once revoked, signing a justice transaction can be done using
1473 /// [`Self::sign_to_local_justice_tx`].
1475 /// It is expected that a watchtower client may use this method to retrieve the latest counterparty
1476 /// commitment transaction(s), and then hold the necessary data until a later update in which
1477 /// the monitor has been updated with the corresponding revocation data, at which point the
1478 /// monitor can sign the justice transaction.
1480 /// This will only return a non-empty list for monitor updates that have been created after
1481 /// upgrading to LDK 0.0.117+. Note that no restriction lies on the monitors themselves, which
1482 /// may have been created prior to upgrading.
1484 /// [`Persist::update_persisted_channel`]: crate::chain::chainmonitor::Persist::update_persisted_channel
1485 pub fn counterparty_commitment_txs_from_update(&self, update: &ChannelMonitorUpdate) -> Vec<CommitmentTransaction> {
1486 self.inner.lock().unwrap().counterparty_commitment_txs_from_update(update)
1489 /// Wrapper around [`EcdsaChannelSigner::sign_justice_revoked_output`] to make
1490 /// signing the justice transaction easier for implementors of
1491 /// [`chain::chainmonitor::Persist`]. On success this method returns the provided transaction
1492 /// signing the input at `input_idx`. This method will only produce a valid signature for
1493 /// a transaction spending the `to_local` output of a commitment transaction, i.e. this cannot
1494 /// be used for revoked HTLC outputs.
1496 /// `Value` is the value of the output being spent by the input at `input_idx`, committed
1497 /// in the BIP 143 signature.
1499 /// This method will only succeed if this monitor has received the revocation secret for the
1500 /// provided `commitment_number`. If a commitment number is provided that does not correspond
1501 /// to the commitment transaction being revoked, this will return a signed transaction, but
1502 /// the signature will not be valid.
1504 /// [`EcdsaChannelSigner::sign_justice_revoked_output`]: crate::sign::EcdsaChannelSigner::sign_justice_revoked_output
1505 /// [`Persist`]: crate::chain::chainmonitor::Persist
1506 pub fn sign_to_local_justice_tx(&self, justice_tx: Transaction, input_idx: usize, value: u64, commitment_number: u64) -> Result<Transaction, ()> {
1507 self.inner.lock().unwrap().sign_to_local_justice_tx(justice_tx, input_idx, value, commitment_number)
1510 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1511 self.inner.lock().unwrap().get_min_seen_secret()
1514 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1515 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1518 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1519 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1522 /// Gets the `node_id` of the counterparty for this channel.
1524 /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
1526 pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
1527 self.inner.lock().unwrap().counterparty_node_id
1530 /// Used by [`ChannelManager`] deserialization to broadcast the latest holder state if its copy
1531 /// of the channel state was out-of-date.
1533 /// You may also use this to broadcast the latest local commitment transaction, either because
1534 /// a monitor update failed or because we've fallen behind (i.e. we've received proof that our
1535 /// counterparty side knows a revocation secret we gave them that they shouldn't know).
1537 /// Broadcasting these transactions in the second case is UNSAFE, as they allow counterparty
1538 /// side to punish you. Nevertheless you may want to broadcast them if counterparty doesn't
1539 /// close channel with their commitment transaction after a substantial amount of time. Best
1540 /// may be to contact the other node operator out-of-band to coordinate other options available
1543 /// [`ChannelManager`]: crate::ln::channelmanager::ChannelManager
1544 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1545 where L::Target: Logger {
1546 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1549 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1550 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1551 /// revoked commitment transaction.
1552 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1553 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1554 where L::Target: Logger {
1555 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1558 /// Processes transactions in a newly connected block, which may result in any of the following:
1559 /// - update the monitor's state against resolved HTLCs
1560 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1561 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1562 /// - detect settled outputs for later spending
1563 /// - schedule and bump any in-flight claims
1565 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1566 /// [`get_outputs_to_watch`].
1568 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1569 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1571 header: &BlockHeader,
1572 txdata: &TransactionData,
1577 ) -> Vec<TransactionOutputs>
1579 B::Target: BroadcasterInterface,
1580 F::Target: FeeEstimator,
1583 self.inner.lock().unwrap().block_connected(
1584 header, txdata, height, broadcaster, fee_estimator, logger)
1587 /// Determines if the disconnected block contained any transactions of interest and updates
1589 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1591 header: &BlockHeader,
1597 B::Target: BroadcasterInterface,
1598 F::Target: FeeEstimator,
1601 self.inner.lock().unwrap().block_disconnected(
1602 header, height, broadcaster, fee_estimator, logger)
1605 /// Processes transactions confirmed in a block with the given header and height, returning new
1606 /// outputs to watch. See [`block_connected`] for details.
1608 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1609 /// blocks. See [`chain::Confirm`] for calling expectations.
1611 /// [`block_connected`]: Self::block_connected
1612 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1614 header: &BlockHeader,
1615 txdata: &TransactionData,
1620 ) -> Vec<TransactionOutputs>
1622 B::Target: BroadcasterInterface,
1623 F::Target: FeeEstimator,
1626 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1627 self.inner.lock().unwrap().transactions_confirmed(
1628 header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
1631 /// Processes a transaction that was reorganized out of the chain.
1633 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1634 /// than blocks. See [`chain::Confirm`] for calling expectations.
1636 /// [`block_disconnected`]: Self::block_disconnected
1637 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1644 B::Target: BroadcasterInterface,
1645 F::Target: FeeEstimator,
1648 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1649 self.inner.lock().unwrap().transaction_unconfirmed(
1650 txid, broadcaster, &bounded_fee_estimator, logger);
1653 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1654 /// [`block_connected`] for details.
1656 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1657 /// blocks. See [`chain::Confirm`] for calling expectations.
1659 /// [`block_connected`]: Self::block_connected
1660 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1662 header: &BlockHeader,
1667 ) -> Vec<TransactionOutputs>
1669 B::Target: BroadcasterInterface,
1670 F::Target: FeeEstimator,
1673 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1674 self.inner.lock().unwrap().best_block_updated(
1675 header, height, broadcaster, &bounded_fee_estimator, logger)
1678 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1679 pub fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
1680 let inner = self.inner.lock().unwrap();
1681 let mut txids: Vec<(Txid, Option<BlockHash>)> = inner.onchain_events_awaiting_threshold_conf
1683 .map(|entry| (entry.txid, entry.block_hash))
1684 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1686 txids.sort_unstable();
1691 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1692 /// [`chain::Confirm`] interfaces.
1693 pub fn current_best_block(&self) -> BestBlock {
1694 self.inner.lock().unwrap().best_block.clone()
1697 /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
1698 /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
1699 /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
1700 /// invoking this every 30 seconds, or lower if running in an environment with spotty
1701 /// connections, like on mobile.
1702 pub fn rebroadcast_pending_claims<B: Deref, F: Deref, L: Deref>(
1703 &self, broadcaster: B, fee_estimator: F, logger: L,
1706 B::Target: BroadcasterInterface,
1707 F::Target: FeeEstimator,
1710 let fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1711 let mut inner = self.inner.lock().unwrap();
1712 let current_height = inner.best_block.height;
1713 inner.onchain_tx_handler.rebroadcast_pending_claims(
1714 current_height, &broadcaster, &fee_estimator, &logger,
1718 /// Returns the descriptors for relevant outputs (i.e., those that we can spend) within the
1719 /// transaction if they exist and the transaction has at least [`ANTI_REORG_DELAY`]
1720 /// confirmations. For [`SpendableOutputDescriptor::DelayedPaymentOutput`] descriptors to be
1721 /// returned, the transaction must have at least `max(ANTI_REORG_DELAY, to_self_delay)`
1724 /// Descriptors returned by this method are primarily exposed via [`Event::SpendableOutputs`]
1725 /// once they are no longer under reorg risk. This method serves as a way to retrieve these
1726 /// descriptors at a later time, either for historical purposes, or to replay any
1727 /// missed/unhandled descriptors. For the purpose of gathering historical records, if the
1728 /// channel close has fully resolved (i.e., [`ChannelMonitor::get_claimable_balances`] returns
1729 /// an empty set), you can retrieve all spendable outputs by providing all descendant spending
1730 /// transactions starting from the channel's funding transaction and going down three levels.
1732 /// `tx` is a transaction we'll scan the outputs of. Any transaction can be provided. If any
1733 /// outputs which can be spent by us are found, at least one descriptor is returned.
1735 /// `confirmation_height` must be the height of the block in which `tx` was included in.
1736 pub fn get_spendable_outputs(&self, tx: &Transaction, confirmation_height: u32) -> Vec<SpendableOutputDescriptor> {
1737 let inner = self.inner.lock().unwrap();
1738 let current_height = inner.best_block.height;
1739 let mut spendable_outputs = inner.get_spendable_outputs(tx);
1740 spendable_outputs.retain(|descriptor| {
1741 let mut conf_threshold = current_height.saturating_sub(ANTI_REORG_DELAY) + 1;
1742 if let SpendableOutputDescriptor::DelayedPaymentOutput(descriptor) = descriptor {
1743 conf_threshold = cmp::min(conf_threshold,
1744 current_height.saturating_sub(descriptor.to_self_delay as u32) + 1);
1746 conf_threshold >= confirmation_height
1752 pub fn get_counterparty_payment_script(&self) -> Script{
1753 self.inner.lock().unwrap().counterparty_payment_script.clone()
1757 pub fn set_counterparty_payment_script(&self, script: Script) {
1758 self.inner.lock().unwrap().counterparty_payment_script = script;
1762 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
1763 /// Helper for get_claimable_balances which does the work for an individual HTLC, generating up
1764 /// to one `Balance` for the HTLC.
1765 fn get_htlc_balance(&self, htlc: &HTLCOutputInCommitment, source: Option<&HTLCSource>,
1766 holder_commitment: bool, counterparty_revoked_commitment: bool,
1767 confirmed_txid: Option<Txid>
1768 ) -> Option<Balance> {
1769 let htlc_commitment_tx_output_idx =
1770 if let Some(v) = htlc.transaction_output_index { v } else { return None; };
1772 let mut htlc_spend_txid_opt = None;
1773 let mut htlc_spend_tx_opt = None;
1774 let mut holder_timeout_spend_pending = None;
1775 let mut htlc_spend_pending = None;
1776 let mut holder_delayed_output_pending = None;
1777 for event in self.onchain_events_awaiting_threshold_conf.iter() {
1779 OnchainEvent::HTLCUpdate { commitment_tx_output_idx, htlc_value_satoshis, .. }
1780 if commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) => {
1781 debug_assert!(htlc_spend_txid_opt.is_none());
1782 htlc_spend_txid_opt = Some(&event.txid);
1783 debug_assert!(htlc_spend_tx_opt.is_none());
1784 htlc_spend_tx_opt = event.transaction.as_ref();
1785 debug_assert!(holder_timeout_spend_pending.is_none());
1786 debug_assert_eq!(htlc_value_satoshis.unwrap(), htlc.amount_msat / 1000);
1787 holder_timeout_spend_pending = Some(event.confirmation_threshold());
1789 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. }
1790 if commitment_tx_output_idx == htlc_commitment_tx_output_idx => {
1791 debug_assert!(htlc_spend_txid_opt.is_none());
1792 htlc_spend_txid_opt = Some(&event.txid);
1793 debug_assert!(htlc_spend_tx_opt.is_none());
1794 htlc_spend_tx_opt = event.transaction.as_ref();
1795 debug_assert!(htlc_spend_pending.is_none());
1796 htlc_spend_pending = Some((event.confirmation_threshold(), preimage.is_some()));
1798 OnchainEvent::MaturingOutput {
1799 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) }
1800 if event.transaction.as_ref().map(|tx| tx.input.iter().enumerate()
1801 .any(|(input_idx, inp)|
1802 Some(inp.previous_output.txid) == confirmed_txid &&
1803 inp.previous_output.vout == htlc_commitment_tx_output_idx &&
1804 // A maturing output for an HTLC claim will always be at the same
1805 // index as the HTLC input. This is true pre-anchors, as there's
1806 // only 1 input and 1 output. This is also true post-anchors,
1807 // because we have a SIGHASH_SINGLE|ANYONECANPAY signature from our
1808 // channel counterparty.
1809 descriptor.outpoint.index as usize == input_idx
1813 debug_assert!(holder_delayed_output_pending.is_none());
1814 holder_delayed_output_pending = Some(event.confirmation_threshold());
1819 let htlc_resolved = self.htlcs_resolved_on_chain.iter()
1820 .find(|v| if v.commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) {
1821 debug_assert!(htlc_spend_txid_opt.is_none());
1822 htlc_spend_txid_opt = v.resolving_txid.as_ref();
1823 debug_assert!(htlc_spend_tx_opt.is_none());
1824 htlc_spend_tx_opt = v.resolving_tx.as_ref();
1827 debug_assert!(holder_timeout_spend_pending.is_some() as u8 + htlc_spend_pending.is_some() as u8 + htlc_resolved.is_some() as u8 <= 1);
1829 let htlc_commitment_outpoint = BitcoinOutPoint::new(confirmed_txid.unwrap(), htlc_commitment_tx_output_idx);
1830 let htlc_output_to_spend =
1831 if let Some(txid) = htlc_spend_txid_opt {
1832 // Because HTLC transactions either only have 1 input and 1 output (pre-anchors) or
1833 // are signed with SIGHASH_SINGLE|ANYONECANPAY under BIP-0143 (post-anchors), we can
1834 // locate the correct output by ensuring its adjacent input spends the HTLC output
1835 // in the commitment.
1836 if let Some(ref tx) = htlc_spend_tx_opt {
1837 let htlc_input_idx_opt = tx.input.iter().enumerate()
1838 .find(|(_, input)| input.previous_output == htlc_commitment_outpoint)
1839 .map(|(idx, _)| idx as u32);
1840 debug_assert!(htlc_input_idx_opt.is_some());
1841 BitcoinOutPoint::new(*txid, htlc_input_idx_opt.unwrap_or(0))
1843 debug_assert!(!self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx());
1844 BitcoinOutPoint::new(*txid, 0)
1847 htlc_commitment_outpoint
1849 let htlc_output_spend_pending = self.onchain_tx_handler.is_output_spend_pending(&htlc_output_to_spend);
1851 if let Some(conf_thresh) = holder_delayed_output_pending {
1852 debug_assert!(holder_commitment);
1853 return Some(Balance::ClaimableAwaitingConfirmations {
1854 amount_satoshis: htlc.amount_msat / 1000,
1855 confirmation_height: conf_thresh,
1857 } else if htlc_resolved.is_some() && !htlc_output_spend_pending {
1858 // Funding transaction spends should be fully confirmed by the time any
1859 // HTLC transactions are resolved, unless we're talking about a holder
1860 // commitment tx, whose resolution is delayed until the CSV timeout is
1861 // reached, even though HTLCs may be resolved after only
1862 // ANTI_REORG_DELAY confirmations.
1863 debug_assert!(holder_commitment || self.funding_spend_confirmed.is_some());
1864 } else if counterparty_revoked_commitment {
1865 let htlc_output_claim_pending = self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1866 if let OnchainEvent::MaturingOutput {
1867 descriptor: SpendableOutputDescriptor::StaticOutput { .. }
1869 if event.transaction.as_ref().map(|tx| tx.input.iter().any(|inp| {
1870 if let Some(htlc_spend_txid) = htlc_spend_txid_opt {
1871 tx.txid() == *htlc_spend_txid || inp.previous_output.txid == *htlc_spend_txid
1873 Some(inp.previous_output.txid) == confirmed_txid &&
1874 inp.previous_output.vout == htlc_commitment_tx_output_idx
1876 })).unwrap_or(false) {
1881 if htlc_output_claim_pending.is_some() {
1882 // We already push `Balance`s onto the `res` list for every
1883 // `StaticOutput` in a `MaturingOutput` in the revoked
1884 // counterparty commitment transaction case generally, so don't
1885 // need to do so again here.
1887 debug_assert!(holder_timeout_spend_pending.is_none(),
1888 "HTLCUpdate OnchainEvents should never appear for preimage claims");
1889 debug_assert!(!htlc.offered || htlc_spend_pending.is_none() || !htlc_spend_pending.unwrap().1,
1890 "We don't (currently) generate preimage claims against revoked outputs, where did you get one?!");
1891 return Some(Balance::CounterpartyRevokedOutputClaimable {
1892 amount_satoshis: htlc.amount_msat / 1000,
1895 } else if htlc.offered == holder_commitment {
1896 // If the payment was outbound, check if there's an HTLCUpdate
1897 // indicating we have spent this HTLC with a timeout, claiming it back
1898 // and awaiting confirmations on it.
1899 if let Some(conf_thresh) = holder_timeout_spend_pending {
1900 return Some(Balance::ClaimableAwaitingConfirmations {
1901 amount_satoshis: htlc.amount_msat / 1000,
1902 confirmation_height: conf_thresh,
1905 let outbound_payment = match source {
1907 debug_assert!(false, "Outbound HTLCs should have a source");
1910 Some(&HTLCSource::PreviousHopData(_)) => false,
1911 Some(&HTLCSource::OutboundRoute { .. }) => true,
1913 return Some(Balance::MaybeTimeoutClaimableHTLC {
1914 amount_satoshis: htlc.amount_msat / 1000,
1915 claimable_height: htlc.cltv_expiry,
1916 payment_hash: htlc.payment_hash,
1920 } else if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1921 // Otherwise (the payment was inbound), only expose it as claimable if
1922 // we know the preimage.
1923 // Note that if there is a pending claim, but it did not use the
1924 // preimage, we lost funds to our counterparty! We will then continue
1925 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1926 debug_assert!(holder_timeout_spend_pending.is_none());
1927 if let Some((conf_thresh, true)) = htlc_spend_pending {
1928 return Some(Balance::ClaimableAwaitingConfirmations {
1929 amount_satoshis: htlc.amount_msat / 1000,
1930 confirmation_height: conf_thresh,
1933 return Some(Balance::ContentiousClaimable {
1934 amount_satoshis: htlc.amount_msat / 1000,
1935 timeout_height: htlc.cltv_expiry,
1936 payment_hash: htlc.payment_hash,
1937 payment_preimage: *payment_preimage,
1940 } else if htlc_resolved.is_none() {
1941 return Some(Balance::MaybePreimageClaimableHTLC {
1942 amount_satoshis: htlc.amount_msat / 1000,
1943 expiry_height: htlc.cltv_expiry,
1944 payment_hash: htlc.payment_hash,
1951 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1952 /// Gets the balances in this channel which are either claimable by us if we were to
1953 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1956 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1957 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1958 /// balance, or until our counterparty has claimed the balance and accrued several
1959 /// confirmations on the claim transaction.
1961 /// Note that for `ChannelMonitors` which track a channel which went on-chain with versions of
1962 /// LDK prior to 0.0.111, not all or excess balances may be included.
1964 /// See [`Balance`] for additional details on the types of claimable balances which
1965 /// may be returned here and their meanings.
1966 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1967 let mut res = Vec::new();
1968 let us = self.inner.lock().unwrap();
1970 let mut confirmed_txid = us.funding_spend_confirmed;
1971 let mut confirmed_counterparty_output = us.confirmed_commitment_tx_counterparty_output;
1972 let mut pending_commitment_tx_conf_thresh = None;
1973 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1974 if let OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } =
1977 confirmed_counterparty_output = commitment_tx_to_counterparty_output;
1978 Some((event.txid, event.confirmation_threshold()))
1981 if let Some((txid, conf_thresh)) = funding_spend_pending {
1982 debug_assert!(us.funding_spend_confirmed.is_none(),
1983 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1984 confirmed_txid = Some(txid);
1985 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1988 macro_rules! walk_htlcs {
1989 ($holder_commitment: expr, $counterparty_revoked_commitment: expr, $htlc_iter: expr) => {
1990 for (htlc, source) in $htlc_iter {
1991 if htlc.transaction_output_index.is_some() {
1993 if let Some(bal) = us.get_htlc_balance(
1994 htlc, source, $holder_commitment, $counterparty_revoked_commitment, confirmed_txid
2003 if let Some(txid) = confirmed_txid {
2004 let mut found_commitment_tx = false;
2005 if let Some(counterparty_tx_htlcs) = us.counterparty_claimable_outpoints.get(&txid) {
2006 // First look for the to_remote output back to us.
2007 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
2008 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
2009 if let OnchainEvent::MaturingOutput {
2010 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
2012 Some(descriptor.output.value)
2015 res.push(Balance::ClaimableAwaitingConfirmations {
2016 amount_satoshis: value,
2017 confirmation_height: conf_thresh,
2020 // If a counterparty commitment transaction is awaiting confirmation, we
2021 // should either have a StaticPaymentOutput MaturingOutput event awaiting
2022 // confirmation with the same height or have never met our dust amount.
2025 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
2026 walk_htlcs!(false, false, counterparty_tx_htlcs.iter().map(|(a, b)| (a, b.as_ref().map(|b| &**b))));
2028 walk_htlcs!(false, true, counterparty_tx_htlcs.iter().map(|(a, b)| (a, b.as_ref().map(|b| &**b))));
2029 // The counterparty broadcasted a revoked state!
2030 // Look for any StaticOutputs first, generating claimable balances for those.
2031 // If any match the confirmed counterparty revoked to_self output, skip
2032 // generating a CounterpartyRevokedOutputClaimable.
2033 let mut spent_counterparty_output = false;
2034 for event in us.onchain_events_awaiting_threshold_conf.iter() {
2035 if let OnchainEvent::MaturingOutput {
2036 descriptor: SpendableOutputDescriptor::StaticOutput { output, .. }
2038 res.push(Balance::ClaimableAwaitingConfirmations {
2039 amount_satoshis: output.value,
2040 confirmation_height: event.confirmation_threshold(),
2042 if let Some(confirmed_to_self_idx) = confirmed_counterparty_output.map(|(idx, _)| idx) {
2043 if event.transaction.as_ref().map(|tx|
2044 tx.input.iter().any(|inp| inp.previous_output.vout == confirmed_to_self_idx)
2045 ).unwrap_or(false) {
2046 spent_counterparty_output = true;
2052 if spent_counterparty_output {
2053 } else if let Some((confirmed_to_self_idx, amt)) = confirmed_counterparty_output {
2054 let output_spendable = us.onchain_tx_handler
2055 .is_output_spend_pending(&BitcoinOutPoint::new(txid, confirmed_to_self_idx));
2056 if output_spendable {
2057 res.push(Balance::CounterpartyRevokedOutputClaimable {
2058 amount_satoshis: amt,
2062 // Counterparty output is missing, either it was broadcasted on a
2063 // previous version of LDK or the counterparty hadn't met dust.
2066 found_commitment_tx = true;
2067 } else if txid == us.current_holder_commitment_tx.txid {
2068 walk_htlcs!(true, false, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())));
2069 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
2070 res.push(Balance::ClaimableAwaitingConfirmations {
2071 amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
2072 confirmation_height: conf_thresh,
2075 found_commitment_tx = true;
2076 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
2077 if txid == prev_commitment.txid {
2078 walk_htlcs!(true, false, prev_commitment.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())));
2079 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
2080 res.push(Balance::ClaimableAwaitingConfirmations {
2081 amount_satoshis: prev_commitment.to_self_value_sat,
2082 confirmation_height: conf_thresh,
2085 found_commitment_tx = true;
2088 if !found_commitment_tx {
2089 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
2090 // We blindly assume this is a cooperative close transaction here, and that
2091 // neither us nor our counterparty misbehaved. At worst we've under-estimated
2092 // the amount we can claim as we'll punish a misbehaving counterparty.
2093 res.push(Balance::ClaimableAwaitingConfirmations {
2094 amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
2095 confirmation_height: conf_thresh,
2100 let mut claimable_inbound_htlc_value_sat = 0;
2101 let mut nondust_htlc_count = 0;
2102 let mut outbound_payment_htlc_rounded_msat = 0;
2103 let mut outbound_forwarded_htlc_rounded_msat = 0;
2104 let mut inbound_claiming_htlc_rounded_msat = 0;
2105 let mut inbound_htlc_rounded_msat = 0;
2106 for (htlc, _, source) in us.current_holder_commitment_tx.htlc_outputs.iter() {
2107 if htlc.transaction_output_index.is_some() {
2108 nondust_htlc_count += 1;
2110 let rounded_value_msat = if htlc.transaction_output_index.is_none() {
2112 } else { htlc.amount_msat % 1000 };
2114 let outbound_payment = match source {
2116 debug_assert!(false, "Outbound HTLCs should have a source");
2119 Some(HTLCSource::PreviousHopData(_)) => false,
2120 Some(HTLCSource::OutboundRoute { .. }) => true,
2122 if outbound_payment {
2123 outbound_payment_htlc_rounded_msat += rounded_value_msat;
2125 outbound_forwarded_htlc_rounded_msat += rounded_value_msat;
2127 if htlc.transaction_output_index.is_some() {
2128 res.push(Balance::MaybeTimeoutClaimableHTLC {
2129 amount_satoshis: htlc.amount_msat / 1000,
2130 claimable_height: htlc.cltv_expiry,
2131 payment_hash: htlc.payment_hash,
2135 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
2136 inbound_claiming_htlc_rounded_msat += rounded_value_msat;
2137 if htlc.transaction_output_index.is_some() {
2138 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
2139 claimable_inbound_htlc_value_msat += htlc.amount_msat;
2142 inbound_htlc_rounded_msat += rounded_value_msat;
2143 if htlc.transaction_output_index.is_some() {
2144 // As long as the HTLC is still in our latest commitment state, treat
2145 // it as potentially claimable, even if it has long-since expired.
2146 res.push(Balance::MaybePreimageClaimableHTLC {
2147 amount_satoshis: htlc.amount_msat / 1000,
2148 expiry_height: htlc.cltv_expiry,
2149 payment_hash: htlc.payment_hash,
2154 res.push(Balance::ClaimableOnChannelClose {
2155 amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
2156 transaction_fee_satoshis: if us.holder_pays_commitment_tx_fee.unwrap_or(true) {
2157 chan_utils::commit_tx_fee_sat(
2158 us.current_holder_commitment_tx.feerate_per_kw, nondust_htlc_count,
2159 us.onchain_tx_handler.channel_type_features())
2161 outbound_payment_htlc_rounded_msat,
2162 outbound_forwarded_htlc_rounded_msat,
2163 inbound_claiming_htlc_rounded_msat,
2164 inbound_htlc_rounded_msat,
2171 /// Gets the set of outbound HTLCs which can be (or have been) resolved by this
2172 /// `ChannelMonitor`. This is used to determine if an HTLC was removed from the channel prior
2173 /// to the `ChannelManager` having been persisted.
2175 /// This is similar to [`Self::get_pending_or_resolved_outbound_htlcs`] except it includes
2176 /// HTLCs which were resolved on-chain (i.e. where the final HTLC resolution was done by an
2177 /// event from this `ChannelMonitor`).
2178 pub(crate) fn get_all_current_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
2179 let mut res = HashMap::new();
2180 // Just examine the available counterparty commitment transactions. See docs on
2181 // `fail_unbroadcast_htlcs`, below, for justification.
2182 let us = self.inner.lock().unwrap();
2183 macro_rules! walk_counterparty_commitment {
2185 if let Some(ref latest_outpoints) = us.counterparty_claimable_outpoints.get($txid) {
2186 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
2187 if let &Some(ref source) = source_option {
2188 res.insert((**source).clone(), (htlc.clone(),
2189 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned()));
2195 if let Some(ref txid) = us.current_counterparty_commitment_txid {
2196 walk_counterparty_commitment!(txid);
2198 if let Some(ref txid) = us.prev_counterparty_commitment_txid {
2199 walk_counterparty_commitment!(txid);
2204 /// Gets the set of outbound HTLCs which are pending resolution in this channel or which were
2205 /// resolved with a preimage from our counterparty.
2207 /// This is used to reconstruct pending outbound payments on restart in the ChannelManager.
2209 /// Currently, the preimage is unused, however if it is present in the relevant internal state
2210 /// an HTLC is always included even if it has been resolved.
2211 pub(crate) fn get_pending_or_resolved_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
2212 let us = self.inner.lock().unwrap();
2213 // We're only concerned with the confirmation count of HTLC transactions, and don't
2214 // actually care how many confirmations a commitment transaction may or may not have. Thus,
2215 // we look for either a FundingSpendConfirmation event or a funding_spend_confirmed.
2216 let confirmed_txid = us.funding_spend_confirmed.or_else(|| {
2217 us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
2218 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
2224 if confirmed_txid.is_none() {
2225 // If we have not seen a commitment transaction on-chain (ie the channel is not yet
2226 // closed), just get the full set.
2228 return self.get_all_current_outbound_htlcs();
2231 let mut res = HashMap::new();
2232 macro_rules! walk_htlcs {
2233 ($holder_commitment: expr, $htlc_iter: expr) => {
2234 for (htlc, source) in $htlc_iter {
2235 if us.htlcs_resolved_on_chain.iter().any(|v| v.commitment_tx_output_idx == htlc.transaction_output_index) {
2236 // We should assert that funding_spend_confirmed is_some() here, but we
2237 // have some unit tests which violate HTLC transaction CSVs entirely and
2239 // TODO: Once tests all connect transactions at consensus-valid times, we
2240 // should assert here like we do in `get_claimable_balances`.
2241 } else if htlc.offered == $holder_commitment {
2242 // If the payment was outbound, check if there's an HTLCUpdate
2243 // indicating we have spent this HTLC with a timeout, claiming it back
2244 // and awaiting confirmations on it.
2245 let htlc_update_confd = us.onchain_events_awaiting_threshold_conf.iter().any(|event| {
2246 if let OnchainEvent::HTLCUpdate { commitment_tx_output_idx: Some(commitment_tx_output_idx), .. } = event.event {
2247 // If the HTLC was timed out, we wait for ANTI_REORG_DELAY blocks
2248 // before considering it "no longer pending" - this matches when we
2249 // provide the ChannelManager an HTLC failure event.
2250 Some(commitment_tx_output_idx) == htlc.transaction_output_index &&
2251 us.best_block.height() >= event.height + ANTI_REORG_DELAY - 1
2252 } else if let OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, .. } = event.event {
2253 // If the HTLC was fulfilled with a preimage, we consider the HTLC
2254 // immediately non-pending, matching when we provide ChannelManager
2256 Some(commitment_tx_output_idx) == htlc.transaction_output_index
2259 let counterparty_resolved_preimage_opt =
2260 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned();
2261 if !htlc_update_confd || counterparty_resolved_preimage_opt.is_some() {
2262 res.insert(source.clone(), (htlc.clone(), counterparty_resolved_preimage_opt));
2269 let txid = confirmed_txid.unwrap();
2270 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
2271 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().filter_map(|(a, b)| {
2272 if let &Some(ref source) = b {
2273 Some((a, &**source))
2276 } else if txid == us.current_holder_commitment_tx.txid {
2277 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().filter_map(|(a, _, c)| {
2278 if let Some(source) = c { Some((a, source)) } else { None }
2280 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
2281 if txid == prev_commitment.txid {
2282 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().filter_map(|(a, _, c)| {
2283 if let Some(source) = c { Some((a, source)) } else { None }
2291 pub(crate) fn get_stored_preimages(&self) -> HashMap<PaymentHash, PaymentPreimage> {
2292 self.inner.lock().unwrap().payment_preimages.clone()
2296 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
2297 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
2298 /// after ANTI_REORG_DELAY blocks.
2300 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
2301 /// are the commitment transactions which are generated by us. The off-chain state machine in
2302 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
2303 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
2304 /// included in a remote commitment transaction are failed back if they are not present in the
2305 /// broadcasted commitment transaction.
2307 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
2308 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
2309 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
2310 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
2311 macro_rules! fail_unbroadcast_htlcs {
2312 ($self: expr, $commitment_tx_type: expr, $commitment_txid_confirmed: expr, $commitment_tx_confirmed: expr,
2313 $commitment_tx_conf_height: expr, $commitment_tx_conf_hash: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
2314 debug_assert_eq!($commitment_tx_confirmed.txid(), $commitment_txid_confirmed);
2316 macro_rules! check_htlc_fails {
2317 ($txid: expr, $commitment_tx: expr) => {
2318 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
2319 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
2320 if let &Some(ref source) = source_option {
2321 // Check if the HTLC is present in the commitment transaction that was
2322 // broadcast, but not if it was below the dust limit, which we should
2323 // fail backwards immediately as there is no way for us to learn the
2324 // payment_preimage.
2325 // Note that if the dust limit were allowed to change between
2326 // commitment transactions we'd want to be check whether *any*
2327 // broadcastable commitment transaction has the HTLC in it, but it
2328 // cannot currently change after channel initialization, so we don't
2330 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
2332 let mut matched_htlc = false;
2333 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
2334 if broadcast_htlc.transaction_output_index.is_some() &&
2335 (Some(&**source) == *broadcast_source ||
2336 (broadcast_source.is_none() &&
2337 broadcast_htlc.payment_hash == htlc.payment_hash &&
2338 broadcast_htlc.amount_msat == htlc.amount_msat)) {
2339 matched_htlc = true;
2343 if matched_htlc { continue; }
2344 if $self.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).is_some() {
2347 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2348 if entry.height != $commitment_tx_conf_height { return true; }
2350 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
2351 *update_source != **source
2356 let entry = OnchainEventEntry {
2357 txid: $commitment_txid_confirmed,
2358 transaction: Some($commitment_tx_confirmed.clone()),
2359 height: $commitment_tx_conf_height,
2360 block_hash: Some(*$commitment_tx_conf_hash),
2361 event: OnchainEvent::HTLCUpdate {
2362 source: (**source).clone(),
2363 payment_hash: htlc.payment_hash.clone(),
2364 htlc_value_satoshis: Some(htlc.amount_msat / 1000),
2365 commitment_tx_output_idx: None,
2368 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction {}, waiting for confirmation (at height {})",
2369 &htlc.payment_hash, $commitment_tx, $commitment_tx_type,
2370 $commitment_txid_confirmed, entry.confirmation_threshold());
2371 $self.onchain_events_awaiting_threshold_conf.push(entry);
2377 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
2378 check_htlc_fails!(txid, "current");
2380 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
2381 check_htlc_fails!(txid, "previous");
2386 // In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
2387 // witness length match (ie is 136 bytes long). We generate one here which we also use in some
2388 // in-line tests later.
2391 pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
2392 use bitcoin::blockdata::opcodes;
2393 let mut ret = [opcodes::all::OP_NOP.to_u8(); 136];
2394 ret[131] = opcodes::all::OP_DROP.to_u8();
2395 ret[132] = opcodes::all::OP_DROP.to_u8();
2396 ret[133] = opcodes::all::OP_DROP.to_u8();
2397 ret[134] = opcodes::all::OP_DROP.to_u8();
2398 ret[135] = opcodes::OP_TRUE.to_u8();
2403 pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
2404 vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
2407 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
2408 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
2409 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
2410 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
2411 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
2412 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
2413 return Err("Previous secret did not match new one");
2416 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
2417 // events for now-revoked/fulfilled HTLCs.
2418 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
2419 if self.current_counterparty_commitment_txid.unwrap() != txid {
2420 let cur_claimables = self.counterparty_claimable_outpoints.get(
2421 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2422 for (_, ref source_opt) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2423 if let Some(source) = source_opt {
2424 if !cur_claimables.iter()
2425 .any(|(_, cur_source_opt)| cur_source_opt == source_opt)
2427 self.counterparty_fulfilled_htlcs.remove(&SentHTLCId::from_source(source));
2431 for &mut (_, ref mut source_opt) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
2435 assert!(cfg!(fuzzing), "Commitment txids are unique outside of fuzzing, where hashes can collide");
2439 if !self.payment_preimages.is_empty() {
2440 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
2441 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
2442 let min_idx = self.get_min_seen_secret();
2443 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
2445 self.payment_preimages.retain(|&k, _| {
2446 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
2447 if k == htlc.payment_hash {
2451 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
2452 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
2453 if k == htlc.payment_hash {
2458 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
2465 counterparty_hash_commitment_number.remove(&k);
2474 pub(crate) fn provide_initial_counterparty_commitment_tx<L: Deref>(
2475 &mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
2476 commitment_number: u64, their_per_commitment_point: PublicKey, feerate_per_kw: u32,
2477 to_broadcaster_value: u64, to_countersignatory_value: u64, logger: &L
2479 where L::Target: Logger
2481 self.initial_counterparty_commitment_info = Some((their_per_commitment_point.clone(),
2482 feerate_per_kw, to_broadcaster_value, to_countersignatory_value));
2484 #[cfg(debug_assertions)] {
2485 let rebuilt_commitment_tx = self.initial_counterparty_commitment_tx().unwrap();
2486 debug_assert_eq!(rebuilt_commitment_tx.trust().txid(), txid);
2489 self.provide_latest_counterparty_commitment_tx(txid, htlc_outputs, commitment_number,
2490 their_per_commitment_point, logger);
2493 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(&mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_per_commitment_point: PublicKey, logger: &L) where L::Target: Logger {
2494 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
2495 // so that a remote monitor doesn't learn anything unless there is a malicious close.
2496 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
2498 for &(ref htlc, _) in &htlc_outputs {
2499 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
2502 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
2503 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
2504 self.current_counterparty_commitment_txid = Some(txid);
2505 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
2506 self.current_counterparty_commitment_number = commitment_number;
2507 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
2508 match self.their_cur_per_commitment_points {
2509 Some(old_points) => {
2510 if old_points.0 == commitment_number + 1 {
2511 self.their_cur_per_commitment_points = Some((old_points.0, old_points.1, Some(their_per_commitment_point)));
2512 } else if old_points.0 == commitment_number + 2 {
2513 if let Some(old_second_point) = old_points.2 {
2514 self.their_cur_per_commitment_points = Some((old_points.0 - 1, old_second_point, Some(their_per_commitment_point)));
2516 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2519 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2523 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2526 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
2527 for htlc in htlc_outputs {
2528 if htlc.0.transaction_output_index.is_some() {
2534 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
2535 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
2536 /// is important that any clones of this channel monitor (including remote clones) by kept
2537 /// up-to-date as our holder commitment transaction is updated.
2538 /// Panics if set_on_holder_tx_csv has never been called.
2539 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, mut htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>, claimed_htlcs: &[(SentHTLCId, PaymentPreimage)], nondust_htlc_sources: Vec<HTLCSource>) -> Result<(), &'static str> {
2540 if htlc_outputs.iter().any(|(_, s, _)| s.is_some()) {
2541 // If we have non-dust HTLCs in htlc_outputs, ensure they match the HTLCs in the
2542 // `holder_commitment_tx`. In the future, we'll no longer provide the redundant data
2543 // and just pass in source data via `nondust_htlc_sources`.
2544 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.trust().htlcs().len());
2545 for (a, b) in htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).map(|(h, _, _)| h).zip(holder_commitment_tx.trust().htlcs().iter()) {
2546 debug_assert_eq!(a, b);
2548 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.counterparty_htlc_sigs.len());
2549 for (a, b) in htlc_outputs.iter().filter_map(|(_, s, _)| s.as_ref()).zip(holder_commitment_tx.counterparty_htlc_sigs.iter()) {
2550 debug_assert_eq!(a, b);
2552 debug_assert!(nondust_htlc_sources.is_empty());
2554 // If we don't have any non-dust HTLCs in htlc_outputs, assume they were all passed via
2555 // `nondust_htlc_sources`, building up the final htlc_outputs by combining
2556 // `nondust_htlc_sources` and the `holder_commitment_tx`
2557 #[cfg(debug_assertions)] {
2559 for htlc in holder_commitment_tx.trust().htlcs().iter() {
2560 assert!(htlc.transaction_output_index.unwrap() as i32 > prev);
2561 prev = htlc.transaction_output_index.unwrap() as i32;
2564 debug_assert!(htlc_outputs.iter().all(|(htlc, _, _)| htlc.transaction_output_index.is_none()));
2565 debug_assert!(htlc_outputs.iter().all(|(_, sig_opt, _)| sig_opt.is_none()));
2566 debug_assert_eq!(holder_commitment_tx.trust().htlcs().len(), holder_commitment_tx.counterparty_htlc_sigs.len());
2568 let mut sources_iter = nondust_htlc_sources.into_iter();
2570 for (htlc, counterparty_sig) in holder_commitment_tx.trust().htlcs().iter()
2571 .zip(holder_commitment_tx.counterparty_htlc_sigs.iter())
2574 let source = sources_iter.next().expect("Non-dust HTLC sources didn't match commitment tx");
2575 #[cfg(debug_assertions)] {
2576 assert!(source.possibly_matches_output(htlc));
2578 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), Some(source)));
2580 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), None));
2583 debug_assert!(sources_iter.next().is_none());
2586 let trusted_tx = holder_commitment_tx.trust();
2587 let txid = trusted_tx.txid();
2588 let tx_keys = trusted_tx.keys();
2589 self.current_holder_commitment_number = trusted_tx.commitment_number();
2590 let mut new_holder_commitment_tx = HolderSignedTx {
2592 revocation_key: tx_keys.revocation_key,
2593 a_htlc_key: tx_keys.broadcaster_htlc_key,
2594 b_htlc_key: tx_keys.countersignatory_htlc_key,
2595 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
2596 per_commitment_point: tx_keys.per_commitment_point,
2598 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
2599 feerate_per_kw: trusted_tx.feerate_per_kw(),
2601 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
2602 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
2603 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
2604 for (claimed_htlc_id, claimed_preimage) in claimed_htlcs {
2605 #[cfg(debug_assertions)] {
2606 let cur_counterparty_htlcs = self.counterparty_claimable_outpoints.get(
2607 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2608 assert!(cur_counterparty_htlcs.iter().any(|(_, source_opt)| {
2609 if let Some(source) = source_opt {
2610 SentHTLCId::from_source(source) == *claimed_htlc_id
2614 self.counterparty_fulfilled_htlcs.insert(*claimed_htlc_id, *claimed_preimage);
2616 if self.holder_tx_signed {
2617 return Err("Latest holder commitment signed has already been signed, update is rejected");
2622 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
2623 /// commitment_tx_infos which contain the payment hash have been revoked.
2624 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
2625 &mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B,
2626 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
2627 where B::Target: BroadcasterInterface,
2628 F::Target: FeeEstimator,
2631 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
2633 let confirmed_spend_txid = self.funding_spend_confirmed.or_else(|| {
2634 self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| match event.event {
2635 OnchainEvent::FundingSpendConfirmation { .. } => Some(event.txid),
2639 let confirmed_spend_txid = if let Some(txid) = confirmed_spend_txid {
2645 // If the channel is force closed, try to claim the output from this preimage.
2646 // First check if a counterparty commitment transaction has been broadcasted:
2647 macro_rules! claim_htlcs {
2648 ($commitment_number: expr, $txid: expr) => {
2649 let (htlc_claim_reqs, _) = self.get_counterparty_output_claim_info($commitment_number, $txid, None);
2650 self.onchain_tx_handler.update_claims_view_from_requests(htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2653 if let Some(txid) = self.current_counterparty_commitment_txid {
2654 if txid == confirmed_spend_txid {
2655 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2656 claim_htlcs!(*commitment_number, txid);
2658 debug_assert!(false);
2659 log_error!(logger, "Detected counterparty commitment tx on-chain without tracking commitment number");
2664 if let Some(txid) = self.prev_counterparty_commitment_txid {
2665 if txid == confirmed_spend_txid {
2666 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2667 claim_htlcs!(*commitment_number, txid);
2669 debug_assert!(false);
2670 log_error!(logger, "Detected counterparty commitment tx on-chain without tracking commitment number");
2676 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
2677 // claiming the HTLC output from each of the holder commitment transactions.
2678 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
2679 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
2680 // holder commitment transactions.
2681 if self.broadcasted_holder_revokable_script.is_some() {
2682 let holder_commitment_tx = if self.current_holder_commitment_tx.txid == confirmed_spend_txid {
2683 Some(&self.current_holder_commitment_tx)
2684 } else if let Some(prev_holder_commitment_tx) = &self.prev_holder_signed_commitment_tx {
2685 if prev_holder_commitment_tx.txid == confirmed_spend_txid {
2686 Some(prev_holder_commitment_tx)
2693 if let Some(holder_commitment_tx) = holder_commitment_tx {
2694 // Assume that the broadcasted commitment transaction confirmed in the current best
2695 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
2697 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&holder_commitment_tx, self.best_block.height());
2698 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2703 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
2704 where B::Target: BroadcasterInterface,
2707 let commit_txs = self.get_latest_holder_commitment_txn(logger);
2708 let mut txs = vec![];
2709 for tx in commit_txs.iter() {
2710 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
2713 broadcaster.broadcast_transactions(&txs);
2714 self.pending_monitor_events.push(MonitorEvent::HolderForceClosed(self.funding_info.0));
2717 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), ()>
2718 where B::Target: BroadcasterInterface,
2719 F::Target: FeeEstimator,
2722 if self.latest_update_id == CLOSED_CHANNEL_UPDATE_ID && updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2723 log_info!(logger, "Applying post-force-closed update to monitor {} with {} change(s).",
2724 log_funding_info!(self), updates.updates.len());
2725 } else if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2726 log_info!(logger, "Applying force close update to monitor {} with {} change(s).",
2727 log_funding_info!(self), updates.updates.len());
2729 log_info!(logger, "Applying update to monitor {}, bringing update_id from {} to {} with {} change(s).",
2730 log_funding_info!(self), self.latest_update_id, updates.update_id, updates.updates.len());
2732 // ChannelMonitor updates may be applied after force close if we receive a preimage for a
2733 // broadcasted commitment transaction HTLC output that we'd like to claim on-chain. If this
2734 // is the case, we no longer have guaranteed access to the monitor's update ID, so we use a
2735 // sentinel value instead.
2737 // The `ChannelManager` may also queue redundant `ChannelForceClosed` updates if it still
2738 // thinks the channel needs to have its commitment transaction broadcast, so we'll allow
2740 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2741 assert_eq!(updates.updates.len(), 1);
2742 match updates.updates[0] {
2743 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
2744 // We should have already seen a `ChannelForceClosed` update if we're trying to
2745 // provide a preimage at this point.
2746 ChannelMonitorUpdateStep::PaymentPreimage { .. } =>
2747 debug_assert_eq!(self.latest_update_id, CLOSED_CHANNEL_UPDATE_ID),
2749 log_error!(logger, "Attempted to apply post-force-close ChannelMonitorUpdate of type {}", updates.updates[0].variant_name());
2750 panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage");
2753 } else if self.latest_update_id + 1 != updates.update_id {
2754 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
2756 let mut ret = Ok(());
2757 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&**fee_estimator);
2758 for update in updates.updates.iter() {
2760 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs, claimed_htlcs, nondust_htlc_sources } => {
2761 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
2762 if self.lockdown_from_offchain { panic!(); }
2763 if let Err(e) = self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone(), &claimed_htlcs, nondust_htlc_sources.clone()) {
2764 log_error!(logger, "Providing latest holder commitment transaction failed/was refused:");
2765 log_error!(logger, " {}", e);
2769 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_per_commitment_point, .. } => {
2770 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
2771 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_per_commitment_point, logger)
2773 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
2774 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
2775 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, &bounded_fee_estimator, logger)
2777 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
2778 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
2779 if let Err(e) = self.provide_secret(*idx, *secret) {
2780 debug_assert!(false, "Latest counterparty commitment secret was invalid");
2781 log_error!(logger, "Providing latest counterparty commitment secret failed/was refused:");
2782 log_error!(logger, " {}", e);
2786 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
2787 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
2788 self.lockdown_from_offchain = true;
2789 if *should_broadcast {
2790 // There's no need to broadcast our commitment transaction if we've seen one
2791 // confirmed (even with 1 confirmation) as it'll be rejected as
2792 // duplicate/conflicting.
2793 let detected_funding_spend = self.funding_spend_confirmed.is_some() ||
2794 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
2795 OnchainEvent::FundingSpendConfirmation { .. } => true,
2798 if detected_funding_spend {
2799 log_trace!(logger, "Avoiding commitment broadcast, already detected confirmed spend onchain");
2802 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
2803 // If the channel supports anchor outputs, we'll need to emit an external
2804 // event to be consumed such that a child transaction is broadcast with a
2805 // high enough feerate for the parent commitment transaction to confirm.
2806 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
2807 let funding_output = HolderFundingOutput::build(
2808 self.funding_redeemscript.clone(), self.channel_value_satoshis,
2809 self.onchain_tx_handler.channel_type_features().clone(),
2811 let best_block_height = self.best_block.height();
2812 let commitment_package = PackageTemplate::build_package(
2813 self.funding_info.0.txid.clone(), self.funding_info.0.index as u32,
2814 PackageSolvingData::HolderFundingOutput(funding_output),
2815 best_block_height, best_block_height
2817 self.onchain_tx_handler.update_claims_view_from_requests(
2818 vec![commitment_package], best_block_height, best_block_height,
2819 broadcaster, &bounded_fee_estimator, logger,
2822 } else if !self.holder_tx_signed {
2823 log_error!(logger, "WARNING: You have a potentially-unsafe holder commitment transaction available to broadcast");
2824 log_error!(logger, " in channel monitor for channel {}!", &self.funding_info.0.to_channel_id());
2825 log_error!(logger, " Read the docs for ChannelMonitor::get_latest_holder_commitment_txn and take manual action!");
2827 // If we generated a MonitorEvent::HolderForceClosed, the ChannelManager
2828 // will still give us a ChannelForceClosed event with !should_broadcast, but we
2829 // shouldn't print the scary warning above.
2830 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
2833 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
2834 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
2835 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
2836 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
2842 #[cfg(debug_assertions)] {
2843 self.counterparty_commitment_txs_from_update(updates);
2846 // If the updates succeeded and we were in an already closed channel state, then there's no
2847 // need to refuse any updates we expect to receive afer seeing a confirmed commitment.
2848 if ret.is_ok() && updates.update_id == CLOSED_CHANNEL_UPDATE_ID && self.latest_update_id == updates.update_id {
2852 self.latest_update_id = updates.update_id;
2854 // Refuse updates after we've detected a spend onchain, but only if we haven't processed a
2855 // force closed monitor update yet.
2856 if ret.is_ok() && self.funding_spend_seen && self.latest_update_id != CLOSED_CHANNEL_UPDATE_ID {
2857 log_error!(logger, "Refusing Channel Monitor Update as counterparty attempted to update commitment after funding was spent");
2862 pub fn get_latest_update_id(&self) -> u64 {
2863 self.latest_update_id
2866 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
2870 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
2871 // If we've detected a counterparty commitment tx on chain, we must include it in the set
2872 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
2873 // its trivial to do, double-check that here.
2874 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
2875 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
2877 &self.outputs_to_watch
2880 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
2881 let mut ret = Vec::new();
2882 mem::swap(&mut ret, &mut self.pending_monitor_events);
2886 /// Gets the set of events that are repeated regularly (e.g. those which RBF bump
2887 /// transactions). We're okay if we lose these on restart as they'll be regenerated for us at
2888 /// some regular interval via [`ChannelMonitor::rebroadcast_pending_claims`].
2889 pub(super) fn get_repeated_events(&mut self) -> Vec<Event> {
2890 let pending_claim_events = self.onchain_tx_handler.get_and_clear_pending_claim_events();
2891 let mut ret = Vec::with_capacity(pending_claim_events.len());
2892 for (claim_id, claim_event) in pending_claim_events {
2894 ClaimEvent::BumpCommitment {
2895 package_target_feerate_sat_per_1000_weight, commitment_tx, anchor_output_idx,
2897 let commitment_txid = commitment_tx.txid();
2898 debug_assert_eq!(self.current_holder_commitment_tx.txid, commitment_txid);
2899 let pending_htlcs = self.current_holder_commitment_tx.non_dust_htlcs();
2900 let commitment_tx_fee_satoshis = self.channel_value_satoshis -
2901 commitment_tx.output.iter().fold(0u64, |sum, output| sum + output.value);
2902 ret.push(Event::BumpTransaction(BumpTransactionEvent::ChannelClose {
2904 package_target_feerate_sat_per_1000_weight,
2906 commitment_tx_fee_satoshis,
2907 anchor_descriptor: AnchorDescriptor {
2908 channel_derivation_parameters: ChannelDerivationParameters {
2909 keys_id: self.channel_keys_id,
2910 value_satoshis: self.channel_value_satoshis,
2911 transaction_parameters: self.onchain_tx_handler.channel_transaction_parameters.clone(),
2913 outpoint: BitcoinOutPoint {
2914 txid: commitment_txid,
2915 vout: anchor_output_idx,
2921 ClaimEvent::BumpHTLC {
2922 target_feerate_sat_per_1000_weight, htlcs, tx_lock_time,
2924 let mut htlc_descriptors = Vec::with_capacity(htlcs.len());
2926 htlc_descriptors.push(HTLCDescriptor {
2927 channel_derivation_parameters: ChannelDerivationParameters {
2928 keys_id: self.channel_keys_id,
2929 value_satoshis: self.channel_value_satoshis,
2930 transaction_parameters: self.onchain_tx_handler.channel_transaction_parameters.clone(),
2932 commitment_txid: htlc.commitment_txid,
2933 per_commitment_number: htlc.per_commitment_number,
2934 per_commitment_point: self.onchain_tx_handler.signer.get_per_commitment_point(
2935 htlc.per_commitment_number, &self.onchain_tx_handler.secp_ctx,
2939 preimage: htlc.preimage,
2940 counterparty_sig: htlc.counterparty_sig,
2943 ret.push(Event::BumpTransaction(BumpTransactionEvent::HTLCResolution {
2945 target_feerate_sat_per_1000_weight,
2955 pub(crate) fn initial_counterparty_commitment_tx(&mut self) -> Option<CommitmentTransaction> {
2956 let (their_per_commitment_point, feerate_per_kw, to_broadcaster_value,
2957 to_countersignatory_value) = self.initial_counterparty_commitment_info?;
2958 let htlc_outputs = vec![];
2960 let commitment_tx = self.build_counterparty_commitment_tx(INITIAL_COMMITMENT_NUMBER,
2961 &their_per_commitment_point, to_broadcaster_value, to_countersignatory_value,
2962 feerate_per_kw, htlc_outputs);
2966 fn build_counterparty_commitment_tx(
2967 &self, commitment_number: u64, their_per_commitment_point: &PublicKey,
2968 to_broadcaster_value: u64, to_countersignatory_value: u64, feerate_per_kw: u32,
2969 mut nondust_htlcs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>
2970 ) -> CommitmentTransaction {
2971 let broadcaster_keys = &self.onchain_tx_handler.channel_transaction_parameters
2972 .counterparty_parameters.as_ref().unwrap().pubkeys;
2973 let countersignatory_keys =
2974 &self.onchain_tx_handler.channel_transaction_parameters.holder_pubkeys;
2976 let broadcaster_funding_key = broadcaster_keys.funding_pubkey;
2977 let countersignatory_funding_key = countersignatory_keys.funding_pubkey;
2978 let keys = TxCreationKeys::from_channel_static_keys(&their_per_commitment_point,
2979 &broadcaster_keys, &countersignatory_keys, &self.onchain_tx_handler.secp_ctx);
2980 let channel_parameters =
2981 &self.onchain_tx_handler.channel_transaction_parameters.as_counterparty_broadcastable();
2983 CommitmentTransaction::new_with_auxiliary_htlc_data(commitment_number,
2984 to_broadcaster_value, to_countersignatory_value, broadcaster_funding_key,
2985 countersignatory_funding_key, keys, feerate_per_kw, &mut nondust_htlcs,
2989 pub(crate) fn counterparty_commitment_txs_from_update(&self, update: &ChannelMonitorUpdate) -> Vec<CommitmentTransaction> {
2990 update.updates.iter().filter_map(|update| {
2992 &ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid,
2993 ref htlc_outputs, commitment_number, their_per_commitment_point,
2994 feerate_per_kw: Some(feerate_per_kw),
2995 to_broadcaster_value_sat: Some(to_broadcaster_value),
2996 to_countersignatory_value_sat: Some(to_countersignatory_value) } => {
2998 let nondust_htlcs = htlc_outputs.iter().filter_map(|(htlc, _)| {
2999 htlc.transaction_output_index.map(|_| (htlc.clone(), None))
3000 }).collect::<Vec<_>>();
3002 let commitment_tx = self.build_counterparty_commitment_tx(commitment_number,
3003 &their_per_commitment_point, to_broadcaster_value,
3004 to_countersignatory_value, feerate_per_kw, nondust_htlcs);
3006 debug_assert_eq!(commitment_tx.trust().txid(), commitment_txid);
3015 pub(crate) fn sign_to_local_justice_tx(
3016 &self, mut justice_tx: Transaction, input_idx: usize, value: u64, commitment_number: u64
3017 ) -> Result<Transaction, ()> {
3018 let secret = self.get_secret(commitment_number).ok_or(())?;
3019 let per_commitment_key = SecretKey::from_slice(&secret).map_err(|_| ())?;
3020 let their_per_commitment_point = PublicKey::from_secret_key(
3021 &self.onchain_tx_handler.secp_ctx, &per_commitment_key);
3023 let revocation_pubkey = chan_utils::derive_public_revocation_key(
3024 &self.onchain_tx_handler.secp_ctx, &their_per_commitment_point,
3025 &self.holder_revocation_basepoint);
3026 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
3027 &their_per_commitment_point,
3028 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
3029 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
3030 self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
3032 let sig = self.onchain_tx_handler.signer.sign_justice_revoked_output(
3033 &justice_tx, input_idx, value, &per_commitment_key, &self.onchain_tx_handler.secp_ctx)?;
3034 justice_tx.input[input_idx].witness.push_bitcoin_signature(&sig.serialize_der(), EcdsaSighashType::All);
3035 justice_tx.input[input_idx].witness.push(&[1u8]);
3036 justice_tx.input[input_idx].witness.push(revokeable_redeemscript.as_bytes());
3040 /// Can only fail if idx is < get_min_seen_secret
3041 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
3042 self.commitment_secrets.get_secret(idx)
3045 pub(crate) fn get_min_seen_secret(&self) -> u64 {
3046 self.commitment_secrets.get_min_seen_secret()
3049 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
3050 self.current_counterparty_commitment_number
3053 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
3054 self.current_holder_commitment_number
3057 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
3058 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
3059 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
3060 /// HTLC-Success/HTLC-Timeout transactions.
3062 /// Returns packages to claim the revoked output(s), as well as additional outputs to watch and
3063 /// general information about the output that is to the counterparty in the commitment
3065 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L)
3066 -> (Vec<PackageTemplate>, TransactionOutputs, CommitmentTxCounterpartyOutputInfo)
3067 where L::Target: Logger {
3068 // Most secp and related errors trying to create keys means we have no hope of constructing
3069 // a spend transaction...so we return no transactions to broadcast
3070 let mut claimable_outpoints = Vec::new();
3071 let mut watch_outputs = Vec::new();
3072 let mut to_counterparty_output_info = None;
3074 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
3075 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
3077 macro_rules! ignore_error {
3078 ( $thing : expr ) => {
3081 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
3086 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence.0 as u64 & 0xffffff) << 3*8) | (tx.lock_time.0 as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
3087 if commitment_number >= self.get_min_seen_secret() {
3088 let secret = self.get_secret(commitment_number).unwrap();
3089 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
3090 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
3091 let revocation_pubkey = chan_utils::derive_public_revocation_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
3092 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx, &PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key), &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
3094 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
3095 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
3097 // First, process non-htlc outputs (to_holder & to_counterparty)
3098 for (idx, outp) in tx.output.iter().enumerate() {
3099 if outp.script_pubkey == revokeable_p2wsh {
3100 let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_commitment_params.on_counterparty_tx_csv, self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx());
3101 let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height);
3102 claimable_outpoints.push(justice_package);
3103 to_counterparty_output_info =
3104 Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value));
3108 // Then, try to find revoked htlc outputs
3109 if let Some(ref per_commitment_data) = per_commitment_option {
3110 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
3111 if let Some(transaction_output_index) = htlc.transaction_output_index {
3112 if transaction_output_index as usize >= tx.output.len() ||
3113 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
3114 // per_commitment_data is corrupt or our commitment signing key leaked!
3115 return (claimable_outpoints, (commitment_txid, watch_outputs),
3116 to_counterparty_output_info);
3118 let revk_htlc_outp = RevokedHTLCOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, htlc.amount_msat / 1000, htlc.clone(), &self.onchain_tx_handler.channel_transaction_parameters.channel_type_features);
3119 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, height);
3120 claimable_outpoints.push(justice_package);
3125 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
3126 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
3127 // We're definitely a counterparty commitment transaction!
3128 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
3129 for (idx, outp) in tx.output.iter().enumerate() {
3130 watch_outputs.push((idx as u32, outp.clone()));
3132 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
3134 if let Some(per_commitment_data) = per_commitment_option {
3135 fail_unbroadcast_htlcs!(self, "revoked_counterparty", commitment_txid, tx, height,
3136 block_hash, per_commitment_data.iter().map(|(htlc, htlc_source)|
3137 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
3140 debug_assert!(false, "We should have per-commitment option for any recognized old commitment txn");
3141 fail_unbroadcast_htlcs!(self, "revoked counterparty", commitment_txid, tx, height,
3142 block_hash, [].iter().map(|reference| *reference), logger);
3145 } else if let Some(per_commitment_data) = per_commitment_option {
3146 // While this isn't useful yet, there is a potential race where if a counterparty
3147 // revokes a state at the same time as the commitment transaction for that state is
3148 // confirmed, and the watchtower receives the block before the user, the user could
3149 // upload a new ChannelMonitor with the revocation secret but the watchtower has
3150 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
3151 // not being generated by the above conditional. Thus, to be safe, we go ahead and
3153 for (idx, outp) in tx.output.iter().enumerate() {
3154 watch_outputs.push((idx as u32, outp.clone()));
3156 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
3158 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
3159 fail_unbroadcast_htlcs!(self, "counterparty", commitment_txid, tx, height, block_hash,
3160 per_commitment_data.iter().map(|(htlc, htlc_source)|
3161 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
3164 let (htlc_claim_reqs, counterparty_output_info) =
3165 self.get_counterparty_output_claim_info(commitment_number, commitment_txid, Some(tx));
3166 to_counterparty_output_info = counterparty_output_info;
3167 for req in htlc_claim_reqs {
3168 claimable_outpoints.push(req);
3172 (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
3175 /// Returns the HTLC claim package templates and the counterparty output info
3176 fn get_counterparty_output_claim_info(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>)
3177 -> (Vec<PackageTemplate>, CommitmentTxCounterpartyOutputInfo) {
3178 let mut claimable_outpoints = Vec::new();
3179 let mut to_counterparty_output_info: CommitmentTxCounterpartyOutputInfo = None;
3181 let htlc_outputs = match self.counterparty_claimable_outpoints.get(&commitment_txid) {
3182 Some(outputs) => outputs,
3183 None => return (claimable_outpoints, to_counterparty_output_info),
3185 let per_commitment_points = match self.their_cur_per_commitment_points {
3186 Some(points) => points,
3187 None => return (claimable_outpoints, to_counterparty_output_info),
3190 let per_commitment_point =
3191 // If the counterparty commitment tx is the latest valid state, use their latest
3192 // per-commitment point
3193 if per_commitment_points.0 == commitment_number { &per_commitment_points.1 }
3194 else if let Some(point) = per_commitment_points.2.as_ref() {
3195 // If counterparty commitment tx is the state previous to the latest valid state, use
3196 // their previous per-commitment point (non-atomicity of revocation means it's valid for
3197 // them to temporarily have two valid commitment txns from our viewpoint)
3198 if per_commitment_points.0 == commitment_number + 1 {
3200 } else { return (claimable_outpoints, to_counterparty_output_info); }
3201 } else { return (claimable_outpoints, to_counterparty_output_info); };
3203 if let Some(transaction) = tx {
3204 let revocation_pubkey = chan_utils::derive_public_revocation_key(
3205 &self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
3206 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
3207 &per_commitment_point,
3208 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
3209 let revokeable_p2wsh = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
3210 self.counterparty_commitment_params.on_counterparty_tx_csv,
3211 &delayed_key).to_v0_p2wsh();
3212 for (idx, outp) in transaction.output.iter().enumerate() {
3213 if outp.script_pubkey == revokeable_p2wsh {
3214 to_counterparty_output_info =
3215 Some((idx.try_into().expect("Can't have > 2^32 outputs"), outp.value));
3220 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
3221 if let Some(transaction_output_index) = htlc.transaction_output_index {
3222 if let Some(transaction) = tx {
3223 if transaction_output_index as usize >= transaction.output.len() ||
3224 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
3225 // per_commitment_data is corrupt or our commitment signing key leaked!
3226 return (claimable_outpoints, to_counterparty_output_info);
3229 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
3230 if preimage.is_some() || !htlc.offered {
3231 let counterparty_htlc_outp = if htlc.offered {
3232 PackageSolvingData::CounterpartyOfferedHTLCOutput(
3233 CounterpartyOfferedHTLCOutput::build(*per_commitment_point,
3234 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
3235 self.counterparty_commitment_params.counterparty_htlc_base_key,
3236 preimage.unwrap(), htlc.clone(), self.onchain_tx_handler.channel_type_features().clone()))
3238 PackageSolvingData::CounterpartyReceivedHTLCOutput(
3239 CounterpartyReceivedHTLCOutput::build(*per_commitment_point,
3240 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
3241 self.counterparty_commitment_params.counterparty_htlc_base_key,
3242 htlc.clone(), self.onchain_tx_handler.channel_type_features().clone()))
3244 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry, 0);
3245 claimable_outpoints.push(counterparty_package);
3250 (claimable_outpoints, to_counterparty_output_info)
3253 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
3254 fn check_spend_counterparty_htlc<L: Deref>(
3255 &mut self, tx: &Transaction, commitment_number: u64, commitment_txid: &Txid, height: u32, logger: &L
3256 ) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
3257 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
3258 let per_commitment_key = match SecretKey::from_slice(&secret) {
3260 Err(_) => return (Vec::new(), None)
3262 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
3264 let htlc_txid = tx.txid();
3265 let mut claimable_outpoints = vec![];
3266 let mut outputs_to_watch = None;
3267 // Previously, we would only claim HTLCs from revoked HTLC transactions if they had 1 input
3268 // with a witness of 5 elements and 1 output. This wasn't enough for anchor outputs, as the
3269 // counterparty can now aggregate multiple HTLCs into a single transaction thanks to
3270 // `SIGHASH_SINGLE` remote signatures, leading us to not claim any HTLCs upon seeing a
3271 // confirmed revoked HTLC transaction (for more details, see
3272 // https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-April/003561.html).
3274 // We make sure we're not vulnerable to this case by checking all inputs of the transaction,
3275 // and claim those which spend the commitment transaction, have a witness of 5 elements, and
3276 // have a corresponding output at the same index within the transaction.
3277 for (idx, input) in tx.input.iter().enumerate() {
3278 if input.previous_output.txid == *commitment_txid && input.witness.len() == 5 && tx.output.get(idx).is_some() {
3279 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, idx);
3280 let revk_outp = RevokedOutput::build(
3281 per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
3282 self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key,
3283 tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv,
3286 let justice_package = PackageTemplate::build_package(
3287 htlc_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp),
3288 height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height
3290 claimable_outpoints.push(justice_package);
3291 if outputs_to_watch.is_none() {
3292 outputs_to_watch = Some((htlc_txid, vec![]));
3294 outputs_to_watch.as_mut().unwrap().1.push((idx as u32, tx.output[idx].clone()));
3297 (claimable_outpoints, outputs_to_watch)
3300 // Returns (1) `PackageTemplate`s that can be given to the OnchainTxHandler, so that the handler can
3301 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
3302 // script so we can detect whether a holder transaction has been seen on-chain.
3303 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
3304 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
3306 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
3307 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
3309 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
3310 if let Some(transaction_output_index) = htlc.transaction_output_index {
3311 let htlc_output = if htlc.offered {
3312 let htlc_output = HolderHTLCOutput::build_offered(
3313 htlc.amount_msat, htlc.cltv_expiry, self.onchain_tx_handler.channel_type_features().clone()
3317 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
3320 // We can't build an HTLC-Success transaction without the preimage
3323 let htlc_output = HolderHTLCOutput::build_accepted(
3324 payment_preimage, htlc.amount_msat, self.onchain_tx_handler.channel_type_features().clone()
3328 let htlc_package = PackageTemplate::build_package(
3329 holder_tx.txid, transaction_output_index,
3330 PackageSolvingData::HolderHTLCOutput(htlc_output),
3331 htlc.cltv_expiry, conf_height
3333 claim_requests.push(htlc_package);
3337 (claim_requests, broadcasted_holder_revokable_script)
3340 // Returns holder HTLC outputs to watch and react to in case of spending.
3341 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
3342 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
3343 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
3344 if let Some(transaction_output_index) = htlc.transaction_output_index {
3345 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
3351 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
3352 /// revoked using data in holder_claimable_outpoints.
3353 /// Should not be used if check_spend_revoked_transaction succeeds.
3354 /// Returns None unless the transaction is definitely one of our commitment transactions.
3355 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
3356 let commitment_txid = tx.txid();
3357 let mut claim_requests = Vec::new();
3358 let mut watch_outputs = Vec::new();
3360 macro_rules! append_onchain_update {
3361 ($updates: expr, $to_watch: expr) => {
3362 claim_requests = $updates.0;
3363 self.broadcasted_holder_revokable_script = $updates.1;
3364 watch_outputs.append(&mut $to_watch);
3368 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
3369 let mut is_holder_tx = false;
3371 if self.current_holder_commitment_tx.txid == commitment_txid {
3372 is_holder_tx = true;
3373 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
3374 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
3375 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
3376 append_onchain_update!(res, to_watch);
3377 fail_unbroadcast_htlcs!(self, "latest holder", commitment_txid, tx, height,
3378 block_hash, self.current_holder_commitment_tx.htlc_outputs.iter()
3379 .map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())), logger);
3380 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
3381 if holder_tx.txid == commitment_txid {
3382 is_holder_tx = true;
3383 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
3384 let res = self.get_broadcasted_holder_claims(holder_tx, height);
3385 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
3386 append_onchain_update!(res, to_watch);
3387 fail_unbroadcast_htlcs!(self, "previous holder", commitment_txid, tx, height, block_hash,
3388 holder_tx.htlc_outputs.iter().map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())),
3394 Some((claim_requests, (commitment_txid, watch_outputs)))
3400 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
3401 log_debug!(logger, "Getting signed latest holder commitment transaction!");
3402 self.holder_tx_signed = true;
3403 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
3404 let txid = commitment_tx.txid();
3405 let mut holder_transactions = vec![commitment_tx];
3406 // When anchor outputs are present, the HTLC transactions are only valid once the commitment
3407 // transaction confirms.
3408 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
3409 return holder_transactions;
3411 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
3412 if let Some(vout) = htlc.0.transaction_output_index {
3413 let preimage = if !htlc.0.offered {
3414 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
3415 // We can't build an HTLC-Success transaction without the preimage
3418 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
3419 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
3420 // current locktime requirements on-chain. We will broadcast them in
3421 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
3422 // Note that we add + 1 as transactions are broadcastable when they can be
3423 // confirmed in the next block.
3426 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
3427 &::bitcoin::OutPoint { txid, vout }, &preimage) {
3428 holder_transactions.push(htlc_tx);
3432 // We throw away the generated waiting_first_conf data as we aren't (yet) confirmed and we don't actually know what the caller wants to do.
3433 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
3437 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
3438 /// Note that this includes possibly-locktimed-in-the-future transactions!
3439 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
3440 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
3441 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
3442 let txid = commitment_tx.txid();
3443 let mut holder_transactions = vec![commitment_tx];
3444 // When anchor outputs are present, the HTLC transactions are only final once the commitment
3445 // transaction confirms due to the CSV 1 encumberance.
3446 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
3447 return holder_transactions;
3449 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
3450 if let Some(vout) = htlc.0.transaction_output_index {
3451 let preimage = if !htlc.0.offered {
3452 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
3453 // We can't build an HTLC-Success transaction without the preimage
3457 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
3458 &::bitcoin::OutPoint { txid, vout }, &preimage) {
3459 holder_transactions.push(htlc_tx);
3466 pub fn block_connected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, txdata: &TransactionData, height: u32, broadcaster: B, fee_estimator: F, logger: L) -> Vec<TransactionOutputs>
3467 where B::Target: BroadcasterInterface,
3468 F::Target: FeeEstimator,
3471 let block_hash = header.block_hash();
3472 self.best_block = BestBlock::new(block_hash, height);
3474 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3475 self.transactions_confirmed(header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
3478 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
3480 header: &BlockHeader,
3483 fee_estimator: &LowerBoundedFeeEstimator<F>,
3485 ) -> Vec<TransactionOutputs>
3487 B::Target: BroadcasterInterface,
3488 F::Target: FeeEstimator,
3491 let block_hash = header.block_hash();
3493 if height > self.best_block.height() {
3494 self.best_block = BestBlock::new(block_hash, height);
3495 self.block_confirmed(height, block_hash, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
3496 } else if block_hash != self.best_block.block_hash() {
3497 self.best_block = BestBlock::new(block_hash, height);
3498 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
3499 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
3501 } else { Vec::new() }
3504 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
3506 header: &BlockHeader,
3507 txdata: &TransactionData,
3510 fee_estimator: &LowerBoundedFeeEstimator<F>,
3512 ) -> Vec<TransactionOutputs>
3514 B::Target: BroadcasterInterface,
3515 F::Target: FeeEstimator,
3518 let txn_matched = self.filter_block(txdata);
3519 for tx in &txn_matched {
3520 let mut output_val = 0;
3521 for out in tx.output.iter() {
3522 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3523 output_val += out.value;
3524 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3528 let block_hash = header.block_hash();
3530 let mut watch_outputs = Vec::new();
3531 let mut claimable_outpoints = Vec::new();
3532 'tx_iter: for tx in &txn_matched {
3533 let txid = tx.txid();
3534 // If a transaction has already been confirmed, ensure we don't bother processing it duplicatively.
3535 if Some(txid) == self.funding_spend_confirmed {
3536 log_debug!(logger, "Skipping redundant processing of funding-spend tx {} as it was previously confirmed", txid);
3539 for ev in self.onchain_events_awaiting_threshold_conf.iter() {
3540 if ev.txid == txid {
3541 if let Some(conf_hash) = ev.block_hash {
3542 assert_eq!(header.block_hash(), conf_hash,
3543 "Transaction {} was already confirmed and is being re-confirmed in a different block.\n\
3544 This indicates a severe bug in the transaction connection logic - a reorg should have been processed first!", ev.txid);
3546 log_debug!(logger, "Skipping redundant processing of confirming tx {} as it was previously confirmed", txid);
3550 for htlc in self.htlcs_resolved_on_chain.iter() {
3551 if Some(txid) == htlc.resolving_txid {
3552 log_debug!(logger, "Skipping redundant processing of HTLC resolution tx {} as it was previously confirmed", txid);
3556 for spendable_txid in self.spendable_txids_confirmed.iter() {
3557 if txid == *spendable_txid {
3558 log_debug!(logger, "Skipping redundant processing of spendable tx {} as it was previously confirmed", txid);
3563 if tx.input.len() == 1 {
3564 // Assuming our keys were not leaked (in which case we're screwed no matter what),
3565 // commitment transactions and HTLC transactions will all only ever have one input
3566 // (except for HTLC transactions for channels with anchor outputs), which is an easy
3567 // way to filter out any potential non-matching txn for lazy filters.
3568 let prevout = &tx.input[0].previous_output;
3569 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
3570 let mut balance_spendable_csv = None;
3571 log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
3572 &self.funding_info.0.to_channel_id(), txid);
3573 self.funding_spend_seen = true;
3574 let mut commitment_tx_to_counterparty_output = None;
3575 if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
3576 let (mut new_outpoints, new_outputs, counterparty_output_idx_sats) =
3577 self.check_spend_counterparty_transaction(&tx, height, &block_hash, &logger);
3578 commitment_tx_to_counterparty_output = counterparty_output_idx_sats;
3579 if !new_outputs.1.is_empty() {
3580 watch_outputs.push(new_outputs);
3582 claimable_outpoints.append(&mut new_outpoints);
3583 if new_outpoints.is_empty() {
3584 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &block_hash, &logger) {
3585 debug_assert!(commitment_tx_to_counterparty_output.is_none(),
3586 "A commitment transaction matched as both a counterparty and local commitment tx?");
3587 if !new_outputs.1.is_empty() {
3588 watch_outputs.push(new_outputs);
3590 claimable_outpoints.append(&mut new_outpoints);
3591 balance_spendable_csv = Some(self.on_holder_tx_csv);
3595 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3597 transaction: Some((*tx).clone()),
3599 block_hash: Some(block_hash),
3600 event: OnchainEvent::FundingSpendConfirmation {
3601 on_local_output_csv: balance_spendable_csv,
3602 commitment_tx_to_counterparty_output,
3607 if tx.input.len() >= 1 {
3608 // While all commitment transactions have one input, HTLC transactions may have more
3609 // if the HTLC was present in an anchor channel. HTLCs can also be resolved in a few
3610 // other ways which can have more than one output.
3611 for tx_input in &tx.input {
3612 let commitment_txid = tx_input.previous_output.txid;
3613 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&commitment_txid) {
3614 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(
3615 &tx, commitment_number, &commitment_txid, height, &logger
3617 claimable_outpoints.append(&mut new_outpoints);
3618 if let Some(new_outputs) = new_outputs_option {
3619 watch_outputs.push(new_outputs);
3621 // Since there may be multiple HTLCs for this channel (all spending the
3622 // same commitment tx) being claimed by the counterparty within the same
3623 // transaction, and `check_spend_counterparty_htlc` already checks all the
3624 // ones relevant to this channel, we can safely break from our loop.
3628 self.is_resolving_htlc_output(&tx, height, &block_hash, &logger);
3630 self.check_tx_and_push_spendable_outputs(&tx, height, &block_hash, &logger);
3634 if height > self.best_block.height() {
3635 self.best_block = BestBlock::new(block_hash, height);
3638 self.block_confirmed(height, block_hash, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
3641 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
3642 /// `self.best_block` before calling if a new best blockchain tip is available. More
3643 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
3644 /// complexity especially in
3645 /// `OnchainTx::update_claims_view_from_requests`/`OnchainTx::update_claims_view_from_matched_txn`.
3647 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
3648 /// confirmed at, even if it is not the current best height.
3649 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
3652 conf_hash: BlockHash,
3653 txn_matched: Vec<&Transaction>,
3654 mut watch_outputs: Vec<TransactionOutputs>,
3655 mut claimable_outpoints: Vec<PackageTemplate>,
3657 fee_estimator: &LowerBoundedFeeEstimator<F>,
3659 ) -> Vec<TransactionOutputs>
3661 B::Target: BroadcasterInterface,
3662 F::Target: FeeEstimator,
3665 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
3666 debug_assert!(self.best_block.height() >= conf_height);
3668 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
3669 if should_broadcast {
3670 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone(), self.channel_value_satoshis, self.onchain_tx_handler.channel_type_features().clone());
3671 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), self.best_block.height());
3672 claimable_outpoints.push(commitment_package);
3673 self.pending_monitor_events.push(MonitorEvent::HolderForceClosed(self.funding_info.0));
3674 // Although we aren't signing the transaction directly here, the transaction will be signed
3675 // in the claim that is queued to OnchainTxHandler. We set holder_tx_signed here to reject
3676 // new channel updates.
3677 self.holder_tx_signed = true;
3678 // We can't broadcast our HTLC transactions while the commitment transaction is
3679 // unconfirmed. We'll delay doing so until we detect the confirmed commitment in
3680 // `transactions_confirmed`.
3681 if !self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
3682 // Because we're broadcasting a commitment transaction, we should construct the package
3683 // assuming it gets confirmed in the next block. Sadly, we have code which considers
3684 // "not yet confirmed" things as discardable, so we cannot do that here.
3685 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
3686 let unsigned_commitment_tx = self.onchain_tx_handler.get_unsigned_holder_commitment_tx();
3687 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &unsigned_commitment_tx);
3688 if !new_outputs.is_empty() {
3689 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
3691 claimable_outpoints.append(&mut new_outpoints);
3695 // Find which on-chain events have reached their confirmation threshold.
3696 let onchain_events_awaiting_threshold_conf =
3697 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
3698 let mut onchain_events_reaching_threshold_conf = Vec::new();
3699 for entry in onchain_events_awaiting_threshold_conf {
3700 if entry.has_reached_confirmation_threshold(&self.best_block) {
3701 onchain_events_reaching_threshold_conf.push(entry);
3703 self.onchain_events_awaiting_threshold_conf.push(entry);
3707 // Used to check for duplicate HTLC resolutions.
3708 #[cfg(debug_assertions)]
3709 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
3711 .filter_map(|entry| match &entry.event {
3712 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
3716 #[cfg(debug_assertions)]
3717 let mut matured_htlcs = Vec::new();
3719 // Produce actionable events from on-chain events having reached their threshold.
3720 for entry in onchain_events_reaching_threshold_conf.drain(..) {
3722 OnchainEvent::HTLCUpdate { ref source, payment_hash, htlc_value_satoshis, commitment_tx_output_idx } => {
3723 // Check for duplicate HTLC resolutions.
3724 #[cfg(debug_assertions)]
3727 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
3728 "An unmature HTLC transaction conflicts with a maturing one; failed to \
3729 call either transaction_unconfirmed for the conflicting transaction \
3730 or block_disconnected for a block containing it.");
3732 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
3733 "A matured HTLC transaction conflicts with a maturing one; failed to \
3734 call either transaction_unconfirmed for the conflicting transaction \
3735 or block_disconnected for a block containing it.");
3736 matured_htlcs.push(source.clone());
3739 log_debug!(logger, "HTLC {} failure update in {} has got enough confirmations to be passed upstream",
3740 &payment_hash, entry.txid);
3741 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3743 payment_preimage: None,
3744 source: source.clone(),
3745 htlc_value_satoshis,
3747 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3748 commitment_tx_output_idx,
3749 resolving_txid: Some(entry.txid),
3750 resolving_tx: entry.transaction,
3751 payment_preimage: None,
3754 OnchainEvent::MaturingOutput { descriptor } => {
3755 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
3756 self.pending_events.push(Event::SpendableOutputs {
3757 outputs: vec![descriptor],
3758 channel_id: Some(self.funding_info.0.to_channel_id()),
3760 self.spendable_txids_confirmed.push(entry.txid);
3762 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
3763 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3764 commitment_tx_output_idx: Some(commitment_tx_output_idx),
3765 resolving_txid: Some(entry.txid),
3766 resolving_tx: entry.transaction,
3767 payment_preimage: preimage,
3770 OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } => {
3771 self.funding_spend_confirmed = Some(entry.txid);
3772 self.confirmed_commitment_tx_counterparty_output = commitment_tx_to_counterparty_output;
3777 self.onchain_tx_handler.update_claims_view_from_requests(claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
3778 self.onchain_tx_handler.update_claims_view_from_matched_txn(&txn_matched, conf_height, conf_hash, self.best_block.height(), broadcaster, fee_estimator, logger);
3780 // Determine new outputs to watch by comparing against previously known outputs to watch,
3781 // updating the latter in the process.
3782 watch_outputs.retain(|&(ref txid, ref txouts)| {
3783 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
3784 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
3788 // If we see a transaction for which we registered outputs previously,
3789 // make sure the registered scriptpubkey at the expected index match
3790 // the actual transaction output one. We failed this case before #653.
3791 for tx in &txn_matched {
3792 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
3793 for idx_and_script in outputs.iter() {
3794 assert!((idx_and_script.0 as usize) < tx.output.len());
3795 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
3803 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
3804 where B::Target: BroadcasterInterface,
3805 F::Target: FeeEstimator,
3808 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
3811 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
3812 //- maturing spendable output has transaction paying us has been disconnected
3813 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
3815 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3816 self.onchain_tx_handler.block_disconnected(height, broadcaster, &bounded_fee_estimator, logger);
3818 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
3821 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
3825 fee_estimator: &LowerBoundedFeeEstimator<F>,
3828 B::Target: BroadcasterInterface,
3829 F::Target: FeeEstimator,
3832 let mut removed_height = None;
3833 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
3834 if entry.txid == *txid {
3835 removed_height = Some(entry.height);
3840 if let Some(removed_height) = removed_height {
3841 log_info!(logger, "transaction_unconfirmed of txid {} implies height {} was reorg'd out", txid, removed_height);
3842 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| if entry.height >= removed_height {
3843 log_info!(logger, "Transaction {} reorg'd out", entry.txid);
3848 debug_assert!(!self.onchain_events_awaiting_threshold_conf.iter().any(|ref entry| entry.txid == *txid));
3850 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
3853 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
3854 /// transactions thereof.
3855 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
3856 let mut matched_txn = HashSet::new();
3857 txdata.iter().filter(|&&(_, tx)| {
3858 let mut matches = self.spends_watched_output(tx);
3859 for input in tx.input.iter() {
3860 if matches { break; }
3861 if matched_txn.contains(&input.previous_output.txid) {
3866 matched_txn.insert(tx.txid());
3869 }).map(|(_, tx)| *tx).collect()
3872 /// Checks if a given transaction spends any watched outputs.
3873 fn spends_watched_output(&self, tx: &Transaction) -> bool {
3874 for input in tx.input.iter() {
3875 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
3876 for (idx, _script_pubkey) in outputs.iter() {
3877 if *idx == input.previous_output.vout {
3880 // If the expected script is a known type, check that the witness
3881 // appears to be spending the correct type (ie that the match would
3882 // actually succeed in BIP 158/159-style filters).
3883 if _script_pubkey.is_v0_p2wsh() {
3884 if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
3885 // In at least one test we use a deliberately bogus witness
3886 // script which hit an old panic. Thus, we check for that here
3887 // and avoid the assert if its the expected bogus script.
3891 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
3892 } else if _script_pubkey.is_v0_p2wpkh() {
3893 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
3894 } else { panic!(); }
3905 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
3906 // There's no need to broadcast our commitment transaction if we've seen one confirmed (even
3907 // with 1 confirmation) as it'll be rejected as duplicate/conflicting.
3908 if self.funding_spend_confirmed.is_some() ||
3909 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
3910 OnchainEvent::FundingSpendConfirmation { .. } => true,
3916 // We need to consider all HTLCs which are:
3917 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
3918 // transactions and we'd end up in a race, or
3919 // * are in our latest holder commitment transaction, as this is the thing we will
3920 // broadcast if we go on-chain.
3921 // Note that we consider HTLCs which were below dust threshold here - while they don't
3922 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
3923 // to the source, and if we don't fail the channel we will have to ensure that the next
3924 // updates that peer sends us are update_fails, failing the channel if not. It's probably
3925 // easier to just fail the channel as this case should be rare enough anyway.
3926 let height = self.best_block.height();
3927 macro_rules! scan_commitment {
3928 ($htlcs: expr, $holder_tx: expr) => {
3929 for ref htlc in $htlcs {
3930 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
3931 // chain with enough room to claim the HTLC without our counterparty being able to
3932 // time out the HTLC first.
3933 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
3934 // concern is being able to claim the corresponding inbound HTLC (on another
3935 // channel) before it expires. In fact, we don't even really care if our
3936 // counterparty here claims such an outbound HTLC after it expired as long as we
3937 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
3938 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
3939 // we give ourselves a few blocks of headroom after expiration before going
3940 // on-chain for an expired HTLC.
3941 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
3942 // from us until we've reached the point where we go on-chain with the
3943 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
3944 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
3945 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
3946 // inbound_cltv == height + CLTV_CLAIM_BUFFER
3947 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
3948 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
3949 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
3950 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
3951 // The final, above, condition is checked for statically in channelmanager
3952 // with CHECK_CLTV_EXPIRY_SANITY_2.
3953 let htlc_outbound = $holder_tx == htlc.offered;
3954 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
3955 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
3956 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
3963 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
3965 if let Some(ref txid) = self.current_counterparty_commitment_txid {
3966 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3967 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3970 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
3971 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3972 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3979 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
3980 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
3981 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3982 'outer_loop: for input in &tx.input {
3983 let mut payment_data = None;
3984 let htlc_claim = HTLCClaim::from_witness(&input.witness);
3985 let revocation_sig_claim = htlc_claim == Some(HTLCClaim::Revocation);
3986 let accepted_preimage_claim = htlc_claim == Some(HTLCClaim::AcceptedPreimage);
3987 #[cfg(not(fuzzing))]
3988 let accepted_timeout_claim = htlc_claim == Some(HTLCClaim::AcceptedTimeout);
3989 let offered_preimage_claim = htlc_claim == Some(HTLCClaim::OfferedPreimage);
3990 #[cfg(not(fuzzing))]
3991 let offered_timeout_claim = htlc_claim == Some(HTLCClaim::OfferedTimeout);
3993 let mut payment_preimage = PaymentPreimage([0; 32]);
3994 if offered_preimage_claim || accepted_preimage_claim {
3995 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3998 macro_rules! log_claim {
3999 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
4000 let outbound_htlc = $holder_tx == $htlc.offered;
4001 // HTLCs must either be claimed by a matching script type or through the
4003 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
4004 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
4005 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
4006 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
4007 // Further, only exactly one of the possible spend paths should have been
4008 // matched by any HTLC spend:
4009 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
4010 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
4011 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
4012 revocation_sig_claim as u8, 1);
4013 if ($holder_tx && revocation_sig_claim) ||
4014 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
4015 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
4016 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
4017 if outbound_htlc { "outbound" } else { "inbound" }, &$htlc.payment_hash,
4018 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back. We can likely claim the HTLC output with a revocation claim" });
4020 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
4021 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
4022 if outbound_htlc { "outbound" } else { "inbound" }, &$htlc.payment_hash,
4023 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
4028 macro_rules! check_htlc_valid_counterparty {
4029 ($counterparty_txid: expr, $htlc_output: expr) => {
4030 if let Some(txid) = $counterparty_txid {
4031 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
4032 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
4033 if let &Some(ref source) = pending_source {
4034 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
4035 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
4044 macro_rules! scan_commitment {
4045 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
4046 for (ref htlc_output, source_option) in $htlcs {
4047 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
4048 if let Some(ref source) = source_option {
4049 log_claim!($tx_info, $holder_tx, htlc_output, true);
4050 // We have a resolution of an HTLC either from one of our latest
4051 // holder commitment transactions or an unrevoked counterparty commitment
4052 // transaction. This implies we either learned a preimage, the HTLC
4053 // has timed out, or we screwed up. In any case, we should now
4054 // resolve the source HTLC with the original sender.
4055 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
4056 } else if !$holder_tx {
4057 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
4058 if payment_data.is_none() {
4059 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
4062 if payment_data.is_none() {
4063 log_claim!($tx_info, $holder_tx, htlc_output, false);
4064 let outbound_htlc = $holder_tx == htlc_output.offered;
4065 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
4066 txid: tx.txid(), height, block_hash: Some(*block_hash), transaction: Some(tx.clone()),
4067 event: OnchainEvent::HTLCSpendConfirmation {
4068 commitment_tx_output_idx: input.previous_output.vout,
4069 preimage: if accepted_preimage_claim || offered_preimage_claim {
4070 Some(payment_preimage) } else { None },
4071 // If this is a payment to us (ie !outbound_htlc), wait for
4072 // the CSV delay before dropping the HTLC from claimable
4073 // balance if the claim was an HTLC-Success transaction (ie
4074 // accepted_preimage_claim).
4075 on_to_local_output_csv: if accepted_preimage_claim && !outbound_htlc {
4076 Some(self.on_holder_tx_csv) } else { None },
4079 continue 'outer_loop;
4086 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
4087 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
4088 "our latest holder commitment tx", true);
4090 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
4091 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
4092 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
4093 "our previous holder commitment tx", true);
4096 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
4097 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
4098 "counterparty commitment tx", false);
4101 // Check that scan_commitment, above, decided there is some source worth relaying an
4102 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
4103 if let Some((source, payment_hash, amount_msat)) = payment_data {
4104 if accepted_preimage_claim {
4105 if !self.pending_monitor_events.iter().any(
4106 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
4107 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
4110 block_hash: Some(*block_hash),
4111 transaction: Some(tx.clone()),
4112 event: OnchainEvent::HTLCSpendConfirmation {
4113 commitment_tx_output_idx: input.previous_output.vout,
4114 preimage: Some(payment_preimage),
4115 on_to_local_output_csv: None,
4118 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
4120 payment_preimage: Some(payment_preimage),
4122 htlc_value_satoshis: Some(amount_msat / 1000),
4125 } else if offered_preimage_claim {
4126 if !self.pending_monitor_events.iter().any(
4127 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
4128 upd.source == source
4130 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
4132 transaction: Some(tx.clone()),
4134 block_hash: Some(*block_hash),
4135 event: OnchainEvent::HTLCSpendConfirmation {
4136 commitment_tx_output_idx: input.previous_output.vout,
4137 preimage: Some(payment_preimage),
4138 on_to_local_output_csv: None,
4141 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
4143 payment_preimage: Some(payment_preimage),
4145 htlc_value_satoshis: Some(amount_msat / 1000),
4149 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
4150 if entry.height != height { return true; }
4152 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
4153 *htlc_source != source
4158 let entry = OnchainEventEntry {
4160 transaction: Some(tx.clone()),
4162 block_hash: Some(*block_hash),
4163 event: OnchainEvent::HTLCUpdate {
4164 source, payment_hash,
4165 htlc_value_satoshis: Some(amount_msat / 1000),
4166 commitment_tx_output_idx: Some(input.previous_output.vout),
4169 log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height {})", &payment_hash, entry.confirmation_threshold());
4170 self.onchain_events_awaiting_threshold_conf.push(entry);
4176 fn get_spendable_outputs(&self, tx: &Transaction) -> Vec<SpendableOutputDescriptor> {
4177 let mut spendable_outputs = Vec::new();
4178 for (i, outp) in tx.output.iter().enumerate() {
4179 if outp.script_pubkey == self.destination_script {
4180 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
4181 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
4182 output: outp.clone(),
4185 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
4186 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
4187 spendable_outputs.push(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
4188 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
4189 per_commitment_point: broadcasted_holder_revokable_script.1,
4190 to_self_delay: self.on_holder_tx_csv,
4191 output: outp.clone(),
4192 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
4193 channel_keys_id: self.channel_keys_id,
4194 channel_value_satoshis: self.channel_value_satoshis,
4198 if self.counterparty_payment_script == outp.script_pubkey {
4199 spendable_outputs.push(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
4200 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
4201 output: outp.clone(),
4202 channel_keys_id: self.channel_keys_id,
4203 channel_value_satoshis: self.channel_value_satoshis,
4204 channel_transaction_parameters: Some(self.onchain_tx_handler.channel_transaction_parameters.clone()),
4207 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
4208 spendable_outputs.push(SpendableOutputDescriptor::StaticOutput {
4209 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
4210 output: outp.clone(),
4217 /// Checks if the confirmed transaction is paying funds back to some address we can assume to
4219 fn check_tx_and_push_spendable_outputs<L: Deref>(
4220 &mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L,
4221 ) where L::Target: Logger {
4222 for spendable_output in self.get_spendable_outputs(tx) {
4223 let entry = OnchainEventEntry {
4225 transaction: Some(tx.clone()),
4227 block_hash: Some(*block_hash),
4228 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
4230 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
4231 self.onchain_events_awaiting_threshold_conf.push(entry);
4236 impl<Signer: WriteableEcdsaChannelSigner, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
4238 T::Target: BroadcasterInterface,
4239 F::Target: FeeEstimator,
4242 fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
4243 self.0.block_connected(header, txdata, height, &*self.1, &*self.2, &*self.3);
4246 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
4247 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
4251 impl<Signer: WriteableEcdsaChannelSigner, M, T: Deref, F: Deref, L: Deref> chain::Confirm for (M, T, F, L)
4253 M: Deref<Target = ChannelMonitor<Signer>>,
4254 T::Target: BroadcasterInterface,
4255 F::Target: FeeEstimator,
4258 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
4259 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
4262 fn transaction_unconfirmed(&self, txid: &Txid) {
4263 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
4266 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
4267 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
4270 fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
4271 self.0.get_relevant_txids()
4275 const MAX_ALLOC_SIZE: usize = 64*1024;
4277 impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP)>
4278 for (BlockHash, ChannelMonitor<SP::Signer>) {
4279 fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP)) -> Result<Self, DecodeError> {
4280 macro_rules! unwrap_obj {
4284 Err(_) => return Err(DecodeError::InvalidValue),
4289 let (entropy_source, signer_provider) = args;
4291 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
4293 let latest_update_id: u64 = Readable::read(reader)?;
4294 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
4296 let destination_script = Readable::read(reader)?;
4297 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
4299 let revokable_address = Readable::read(reader)?;
4300 let per_commitment_point = Readable::read(reader)?;
4301 let revokable_script = Readable::read(reader)?;
4302 Some((revokable_address, per_commitment_point, revokable_script))
4305 _ => return Err(DecodeError::InvalidValue),
4307 let mut counterparty_payment_script: Script = Readable::read(reader)?;
4308 let shutdown_script = {
4309 let script = <Script as Readable>::read(reader)?;
4310 if script.is_empty() { None } else { Some(script) }
4313 let channel_keys_id = Readable::read(reader)?;
4314 let holder_revocation_basepoint = Readable::read(reader)?;
4315 // Technically this can fail and serialize fail a round-trip, but only for serialization of
4316 // barely-init'd ChannelMonitors that we can't do anything with.
4317 let outpoint = OutPoint {
4318 txid: Readable::read(reader)?,
4319 index: Readable::read(reader)?,
4321 let funding_info = (outpoint, Readable::read(reader)?);
4322 let current_counterparty_commitment_txid = Readable::read(reader)?;
4323 let prev_counterparty_commitment_txid = Readable::read(reader)?;
4325 let counterparty_commitment_params = Readable::read(reader)?;
4326 let funding_redeemscript = Readable::read(reader)?;
4327 let channel_value_satoshis = Readable::read(reader)?;
4329 let their_cur_per_commitment_points = {
4330 let first_idx = <U48 as Readable>::read(reader)?.0;
4334 let first_point = Readable::read(reader)?;
4335 let second_point_slice: [u8; 33] = Readable::read(reader)?;
4336 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
4337 Some((first_idx, first_point, None))
4339 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
4344 let on_holder_tx_csv: u16 = Readable::read(reader)?;
4346 let commitment_secrets = Readable::read(reader)?;
4348 macro_rules! read_htlc_in_commitment {
4351 let offered: bool = Readable::read(reader)?;
4352 let amount_msat: u64 = Readable::read(reader)?;
4353 let cltv_expiry: u32 = Readable::read(reader)?;
4354 let payment_hash: PaymentHash = Readable::read(reader)?;
4355 let transaction_output_index: Option<u32> = Readable::read(reader)?;
4357 HTLCOutputInCommitment {
4358 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
4364 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
4365 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
4366 for _ in 0..counterparty_claimable_outpoints_len {
4367 let txid: Txid = Readable::read(reader)?;
4368 let htlcs_count: u64 = Readable::read(reader)?;
4369 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
4370 for _ in 0..htlcs_count {
4371 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
4373 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
4374 return Err(DecodeError::InvalidValue);
4378 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
4379 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
4380 for _ in 0..counterparty_commitment_txn_on_chain_len {
4381 let txid: Txid = Readable::read(reader)?;
4382 let commitment_number = <U48 as Readable>::read(reader)?.0;
4383 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
4384 return Err(DecodeError::InvalidValue);
4388 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
4389 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
4390 for _ in 0..counterparty_hash_commitment_number_len {
4391 let payment_hash: PaymentHash = Readable::read(reader)?;
4392 let commitment_number = <U48 as Readable>::read(reader)?.0;
4393 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
4394 return Err(DecodeError::InvalidValue);
4398 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
4399 match <u8 as Readable>::read(reader)? {
4402 Some(Readable::read(reader)?)
4404 _ => return Err(DecodeError::InvalidValue),
4406 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
4408 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
4409 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
4411 let payment_preimages_len: u64 = Readable::read(reader)?;
4412 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
4413 for _ in 0..payment_preimages_len {
4414 let preimage: PaymentPreimage = Readable::read(reader)?;
4415 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
4416 if let Some(_) = payment_preimages.insert(hash, preimage) {
4417 return Err(DecodeError::InvalidValue);
4421 let pending_monitor_events_len: u64 = Readable::read(reader)?;
4422 let mut pending_monitor_events = Some(
4423 Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
4424 for _ in 0..pending_monitor_events_len {
4425 let ev = match <u8 as Readable>::read(reader)? {
4426 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
4427 1 => MonitorEvent::HolderForceClosed(funding_info.0),
4428 _ => return Err(DecodeError::InvalidValue)
4430 pending_monitor_events.as_mut().unwrap().push(ev);
4433 let pending_events_len: u64 = Readable::read(reader)?;
4434 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
4435 for _ in 0..pending_events_len {
4436 if let Some(event) = MaybeReadable::read(reader)? {
4437 pending_events.push(event);
4441 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
4443 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
4444 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
4445 for _ in 0..waiting_threshold_conf_len {
4446 if let Some(val) = MaybeReadable::read(reader)? {
4447 onchain_events_awaiting_threshold_conf.push(val);
4451 let outputs_to_watch_len: u64 = Readable::read(reader)?;
4452 let mut outputs_to_watch = HashMap::with_capacity(cmp::min(outputs_to_watch_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<Txid>() + mem::size_of::<u32>() + mem::size_of::<Vec<Script>>())));
4453 for _ in 0..outputs_to_watch_len {
4454 let txid = Readable::read(reader)?;
4455 let outputs_len: u64 = Readable::read(reader)?;
4456 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
4457 for _ in 0..outputs_len {
4458 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
4460 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
4461 return Err(DecodeError::InvalidValue);
4464 let onchain_tx_handler: OnchainTxHandler<SP::Signer> = ReadableArgs::read(
4465 reader, (entropy_source, signer_provider, channel_value_satoshis, channel_keys_id)
4468 let lockdown_from_offchain = Readable::read(reader)?;
4469 let holder_tx_signed = Readable::read(reader)?;
4471 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
4472 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
4473 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
4474 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
4475 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
4476 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
4477 return Err(DecodeError::InvalidValue);
4481 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
4482 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
4483 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
4484 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
4485 return Err(DecodeError::InvalidValue);
4488 let mut funding_spend_confirmed = None;
4489 let mut htlcs_resolved_on_chain = Some(Vec::new());
4490 let mut funding_spend_seen = Some(false);
4491 let mut counterparty_node_id = None;
4492 let mut confirmed_commitment_tx_counterparty_output = None;
4493 let mut spendable_txids_confirmed = Some(Vec::new());
4494 let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
4495 let mut initial_counterparty_commitment_info = None;
4496 let mut holder_pays_commitment_tx_fee = None;
4497 read_tlv_fields!(reader, {
4498 (1, funding_spend_confirmed, option),
4499 (3, htlcs_resolved_on_chain, optional_vec),
4500 (5, pending_monitor_events, optional_vec),
4501 (7, funding_spend_seen, option),
4502 (9, counterparty_node_id, option),
4503 (11, confirmed_commitment_tx_counterparty_output, option),
4504 (13, spendable_txids_confirmed, optional_vec),
4505 (15, counterparty_fulfilled_htlcs, option),
4506 (17, initial_counterparty_commitment_info, option),
4507 (19, holder_pays_commitment_tx_fee, option),
4510 // Monitors for anchor outputs channels opened in v0.0.116 suffered from a bug in which the
4511 // wrong `counterparty_payment_script` was being tracked. Fix it now on deserialization to
4512 // give them a chance to recognize the spendable output.
4513 if onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() &&
4514 counterparty_payment_script.is_v0_p2wpkh()
4516 let payment_point = onchain_tx_handler.channel_transaction_parameters.holder_pubkeys.payment_point;
4517 counterparty_payment_script =
4518 chan_utils::get_to_countersignatory_with_anchors_redeemscript(&payment_point).to_v0_p2wsh();
4521 Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
4523 commitment_transaction_number_obscure_factor,
4526 broadcasted_holder_revokable_script,
4527 counterparty_payment_script,
4531 holder_revocation_basepoint,
4533 current_counterparty_commitment_txid,
4534 prev_counterparty_commitment_txid,
4536 counterparty_commitment_params,
4537 funding_redeemscript,
4538 channel_value_satoshis,
4539 their_cur_per_commitment_points,
4544 counterparty_claimable_outpoints,
4545 counterparty_commitment_txn_on_chain,
4546 counterparty_hash_commitment_number,
4547 counterparty_fulfilled_htlcs: counterparty_fulfilled_htlcs.unwrap(),
4549 prev_holder_signed_commitment_tx,
4550 current_holder_commitment_tx,
4551 current_counterparty_commitment_number,
4552 current_holder_commitment_number,
4555 pending_monitor_events: pending_monitor_events.unwrap(),
4557 is_processing_pending_events: false,
4559 onchain_events_awaiting_threshold_conf,
4564 lockdown_from_offchain,
4566 holder_pays_commitment_tx_fee,
4567 funding_spend_seen: funding_spend_seen.unwrap(),
4568 funding_spend_confirmed,
4569 confirmed_commitment_tx_counterparty_output,
4570 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
4571 spendable_txids_confirmed: spendable_txids_confirmed.unwrap(),
4574 counterparty_node_id,
4575 initial_counterparty_commitment_info,
4582 use bitcoin::blockdata::script::{Script, Builder};
4583 use bitcoin::blockdata::opcodes;
4584 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
4585 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
4586 use bitcoin::util::sighash;
4587 use bitcoin::hashes::Hash;
4588 use bitcoin::hashes::sha256::Hash as Sha256;
4589 use bitcoin::hashes::hex::FromHex;
4590 use bitcoin::hash_types::{BlockHash, Txid};
4591 use bitcoin::network::constants::Network;
4592 use bitcoin::secp256k1::{SecretKey,PublicKey};
4593 use bitcoin::secp256k1::Secp256k1;
4597 use crate::chain::chaininterface::LowerBoundedFeeEstimator;
4599 use super::ChannelMonitorUpdateStep;
4600 use crate::{check_added_monitors, check_spends, get_local_commitment_txn, get_monitor, get_route_and_payment_hash, unwrap_send_err};
4601 use crate::chain::{BestBlock, Confirm};
4602 use crate::chain::channelmonitor::ChannelMonitor;
4603 use crate::chain::package::{weight_offered_htlc, weight_received_htlc, weight_revoked_offered_htlc, weight_revoked_received_htlc, WEIGHT_REVOKED_OUTPUT};
4604 use crate::chain::transaction::OutPoint;
4605 use crate::sign::InMemorySigner;
4606 use crate::ln::{PaymentPreimage, PaymentHash};
4607 use crate::ln::chan_utils;
4608 use crate::ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
4609 use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
4610 use crate::ln::functional_test_utils::*;
4611 use crate::ln::script::ShutdownScript;
4612 use crate::util::errors::APIError;
4613 use crate::util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
4614 use crate::util::ser::{ReadableArgs, Writeable};
4615 use crate::sync::{Arc, Mutex};
4617 use bitcoin::{PackedLockTime, Sequence, Witness};
4618 use crate::ln::features::ChannelTypeFeatures;
4619 use crate::prelude::*;
4621 fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
4622 // Previously, monitor updates were allowed freely even after a funding-spend transaction
4623 // confirmed. This would allow a race condition where we could receive a payment (including
4624 // the counterparty revoking their broadcasted state!) and accept it without recourse as
4625 // long as the ChannelMonitor receives the block first, the full commitment update dance
4626 // occurs after the block is connected, and before the ChannelManager receives the block.
4627 // Obviously this is an incredibly contrived race given the counterparty would be risking
4628 // their full channel balance for it, but its worth fixing nonetheless as it makes the
4629 // potential ChannelMonitor states simpler to reason about.
4631 // This test checks said behavior, as well as ensuring a ChannelMonitorUpdate with multiple
4632 // updates is handled correctly in such conditions.
4633 let chanmon_cfgs = create_chanmon_cfgs(3);
4634 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4635 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
4636 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4637 let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
4638 create_announced_chan_between_nodes(&nodes, 1, 2);
4640 // Rebalance somewhat
4641 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
4643 // First route two payments for testing at the end
4644 let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4645 let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4647 let local_txn = get_local_commitment_txn!(nodes[1], channel.2);
4648 assert_eq!(local_txn.len(), 1);
4649 let remote_txn = get_local_commitment_txn!(nodes[0], channel.2);
4650 assert_eq!(remote_txn.len(), 3); // Commitment and two HTLC-Timeouts
4651 check_spends!(remote_txn[1], remote_txn[0]);
4652 check_spends!(remote_txn[2], remote_txn[0]);
4653 let broadcast_tx = if use_local_txn { &local_txn[0] } else { &remote_txn[0] };
4655 // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
4656 // channel is now closed, but the ChannelManager doesn't know that yet.
4657 let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
4658 let conf_height = nodes[0].best_block_info().1 + 1;
4659 nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
4660 &[(0, broadcast_tx)], conf_height);
4662 let (_, pre_update_monitor) = <(BlockHash, ChannelMonitor<InMemorySigner>)>::read(
4663 &mut io::Cursor::new(&get_monitor!(nodes[1], channel.2).encode()),
4664 (&nodes[1].keys_manager.backing, &nodes[1].keys_manager.backing)).unwrap();
4666 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
4667 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
4668 let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[1], nodes[0], 100_000);
4669 unwrap_send_err!(nodes[1].node.send_payment_with_route(&route, payment_hash,
4670 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
4671 ), false, APIError::MonitorUpdateInProgress, {});
4672 check_added_monitors!(nodes[1], 1);
4674 // Build a new ChannelMonitorUpdate which contains both the failing commitment tx update
4675 // and provides the claim preimages for the two pending HTLCs. The first update generates
4676 // an error, but the point of this test is to ensure the later updates are still applied.
4677 let monitor_updates = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
4678 let mut replay_update = monitor_updates.get(&channel.2).unwrap().iter().rev().next().unwrap().clone();
4679 assert_eq!(replay_update.updates.len(), 1);
4680 if let ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } = replay_update.updates[0] {
4681 } else { panic!(); }
4682 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_1 });
4683 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_2 });
4685 let broadcaster = TestBroadcaster::with_blocks(Arc::clone(&nodes[1].blocks));
4687 pre_update_monitor.update_monitor(&replay_update, &&broadcaster, &&chanmon_cfgs[1].fee_estimator, &nodes[1].logger)
4689 // Even though we error'd on the first update, we should still have generated an HTLC claim
4691 let txn_broadcasted = broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
4692 assert!(txn_broadcasted.len() >= 2);
4693 let htlc_txn = txn_broadcasted.iter().filter(|tx| {
4694 assert_eq!(tx.input.len(), 1);
4695 tx.input[0].previous_output.txid == broadcast_tx.txid()
4696 }).collect::<Vec<_>>();
4697 assert_eq!(htlc_txn.len(), 2);
4698 check_spends!(htlc_txn[0], broadcast_tx);
4699 check_spends!(htlc_txn[1], broadcast_tx);
4702 fn test_funding_spend_refuses_updates() {
4703 do_test_funding_spend_refuses_updates(true);
4704 do_test_funding_spend_refuses_updates(false);
4708 fn test_prune_preimages() {
4709 let secp_ctx = Secp256k1::new();
4710 let logger = Arc::new(TestLogger::new());
4711 let broadcaster = Arc::new(TestBroadcaster::new(Network::Testnet));
4712 let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
4714 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4716 let mut preimages = Vec::new();
4719 let preimage = PaymentPreimage([i; 32]);
4720 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
4721 preimages.push((preimage, hash));
4725 macro_rules! preimages_slice_to_htlcs {
4726 ($preimages_slice: expr) => {
4728 let mut res = Vec::new();
4729 for (idx, preimage) in $preimages_slice.iter().enumerate() {
4730 res.push((HTLCOutputInCommitment {
4734 payment_hash: preimage.1.clone(),
4735 transaction_output_index: Some(idx as u32),
4742 macro_rules! preimages_slice_to_htlc_outputs {
4743 ($preimages_slice: expr) => {
4744 preimages_slice_to_htlcs!($preimages_slice).into_iter().map(|(htlc, _)| (htlc, None)).collect()
4747 let dummy_sig = crate::util::crypto::sign(&secp_ctx,
4748 &bitcoin::secp256k1::Message::from_slice(&[42; 32]).unwrap(),
4749 &SecretKey::from_slice(&[42; 32]).unwrap());
4751 macro_rules! test_preimages_exist {
4752 ($preimages_slice: expr, $monitor: expr) => {
4753 for preimage in $preimages_slice {
4754 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
4759 let keys = InMemorySigner::new(
4761 SecretKey::from_slice(&[41; 32]).unwrap(),
4762 SecretKey::from_slice(&[41; 32]).unwrap(),
4763 SecretKey::from_slice(&[41; 32]).unwrap(),
4764 SecretKey::from_slice(&[41; 32]).unwrap(),
4765 SecretKey::from_slice(&[41; 32]).unwrap(),
4772 let counterparty_pubkeys = ChannelPublicKeys {
4773 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
4774 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
4775 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
4776 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
4777 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
4779 let funding_outpoint = OutPoint { txid: Txid::all_zeros(), index: u16::max_value() };
4780 let channel_parameters = ChannelTransactionParameters {
4781 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
4782 holder_selected_contest_delay: 66,
4783 is_outbound_from_holder: true,
4784 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
4785 pubkeys: counterparty_pubkeys,
4786 selected_contest_delay: 67,
4788 funding_outpoint: Some(funding_outpoint),
4789 channel_type_features: ChannelTypeFeatures::only_static_remote_key()
4791 // Prune with one old state and a holder commitment tx holding a few overlaps with the
4793 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4794 let best_block = BestBlock::from_network(Network::Testnet);
4795 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
4796 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
4797 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
4798 &channel_parameters, true, Script::new(), 46, 0, HolderCommitmentTransaction::dummy(&mut Vec::new()),
4799 best_block, dummy_key);
4801 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..10]);
4802 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4803 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4804 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4805 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"1").into_inner()),
4806 preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
4807 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"2").into_inner()),
4808 preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
4809 for &(ref preimage, ref hash) in preimages.iter() {
4810 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
4811 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
4814 // Now provide a secret, pruning preimages 10-15
4815 let mut secret = [0; 32];
4816 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
4817 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
4818 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
4819 test_preimages_exist!(&preimages[0..10], monitor);
4820 test_preimages_exist!(&preimages[15..20], monitor);
4822 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"3").into_inner()),
4823 preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
4825 // Now provide a further secret, pruning preimages 15-17
4826 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
4827 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
4828 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
4829 test_preimages_exist!(&preimages[0..10], monitor);
4830 test_preimages_exist!(&preimages[17..20], monitor);
4832 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"4").into_inner()),
4833 preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
4835 // Now update holder commitment tx info, pruning only element 18 as we still care about the
4836 // previous commitment tx's preimages too
4837 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..5]);
4838 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4839 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4840 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4841 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
4842 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
4843 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
4844 test_preimages_exist!(&preimages[0..10], monitor);
4845 test_preimages_exist!(&preimages[18..20], monitor);
4847 // But if we do it again, we'll prune 5-10
4848 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..3]);
4849 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4850 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx,
4851 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4852 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
4853 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
4854 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
4855 test_preimages_exist!(&preimages[0..5], monitor);
4859 fn test_claim_txn_weight_computation() {
4860 // We test Claim txn weight, knowing that we want expected weigth and
4861 // not actual case to avoid sigs and time-lock delays hell variances.
4863 let secp_ctx = Secp256k1::new();
4864 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
4865 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
4867 macro_rules! sign_input {
4868 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr, $opt_anchors: expr) => {
4869 let htlc = HTLCOutputInCommitment {
4870 offered: if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_offered_htlc($opt_anchors) { true } else { false },
4872 cltv_expiry: 2 << 16,
4873 payment_hash: PaymentHash([1; 32]),
4874 transaction_output_index: Some($idx as u32),
4876 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, $opt_anchors, &pubkey, &pubkey, &pubkey) };
4877 let sighash = hash_to_message!(&$sighash_parts.segwit_signature_hash($idx, &redeem_script, $amount, EcdsaSighashType::All).unwrap()[..]);
4878 let sig = secp_ctx.sign_ecdsa(&sighash, &privkey);
4879 let mut ser_sig = sig.serialize_der().to_vec();
4880 ser_sig.push(EcdsaSighashType::All as u8);
4881 $sum_actual_sigs += ser_sig.len();
4882 let witness = $sighash_parts.witness_mut($idx).unwrap();
4883 witness.push(ser_sig);
4884 if *$weight == WEIGHT_REVOKED_OUTPUT {
4885 witness.push(vec!(1));
4886 } else if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_revoked_received_htlc($opt_anchors) {
4887 witness.push(pubkey.clone().serialize().to_vec());
4888 } else if *$weight == weight_received_htlc($opt_anchors) {
4889 witness.push(vec![0]);
4891 witness.push(PaymentPreimage([1; 32]).0.to_vec());
4893 witness.push(redeem_script.into_bytes());
4894 let witness = witness.to_vec();
4895 println!("witness[0] {}", witness[0].len());
4896 println!("witness[1] {}", witness[1].len());
4897 println!("witness[2] {}", witness[2].len());
4901 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
4902 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
4904 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
4905 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4906 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4907 let mut sum_actual_sigs = 0;
4909 claim_tx.input.push(TxIn {
4910 previous_output: BitcoinOutPoint {
4914 script_sig: Script::new(),
4915 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4916 witness: Witness::new(),
4919 claim_tx.output.push(TxOut {
4920 script_pubkey: script_pubkey.clone(),
4923 let base_weight = claim_tx.weight();
4924 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, weight_revoked_offered_htlc(channel_type_features), weight_revoked_offered_htlc(channel_type_features), weight_revoked_received_htlc(channel_type_features)];
4925 let mut inputs_total_weight = 2; // count segwit flags
4927 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4928 for (idx, inp) in inputs_weight.iter().enumerate() {
4929 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4930 inputs_total_weight += inp;
4933 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4936 // Claim tx with 1 offered HTLCs, 3 received HTLCs
4937 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4938 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4939 let mut sum_actual_sigs = 0;
4941 claim_tx.input.push(TxIn {
4942 previous_output: BitcoinOutPoint {
4946 script_sig: Script::new(),
4947 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4948 witness: Witness::new(),
4951 claim_tx.output.push(TxOut {
4952 script_pubkey: script_pubkey.clone(),
4955 let base_weight = claim_tx.weight();
4956 let inputs_weight = vec![weight_offered_htlc(channel_type_features), weight_received_htlc(channel_type_features), weight_received_htlc(channel_type_features), weight_received_htlc(channel_type_features)];
4957 let mut inputs_total_weight = 2; // count segwit flags
4959 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4960 for (idx, inp) in inputs_weight.iter().enumerate() {
4961 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4962 inputs_total_weight += inp;
4965 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4968 // Justice tx with 1 revoked HTLC-Success tx output
4969 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4970 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4971 let mut sum_actual_sigs = 0;
4972 claim_tx.input.push(TxIn {
4973 previous_output: BitcoinOutPoint {
4977 script_sig: Script::new(),
4978 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4979 witness: Witness::new(),
4981 claim_tx.output.push(TxOut {
4982 script_pubkey: script_pubkey.clone(),
4985 let base_weight = claim_tx.weight();
4986 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
4987 let mut inputs_total_weight = 2; // count segwit flags
4989 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4990 for (idx, inp) in inputs_weight.iter().enumerate() {
4991 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4992 inputs_total_weight += inp;
4995 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
4999 // Further testing is done in the ChannelManager integration tests.