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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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::{TxOut,Transaction};
25 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
26 use bitcoin::blockdata::script::{Script, Builder};
27 use bitcoin::blockdata::opcodes;
29 use bitcoin::hashes::Hash;
30 use bitcoin::hashes::sha256::Hash as Sha256;
31 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
33 use bitcoin::secp256k1::{Secp256k1, ecdsa::Signature};
34 use bitcoin::secp256k1::{SecretKey, PublicKey};
35 use bitcoin::secp256k1;
37 use ln::{PaymentHash, PaymentPreimage};
38 use ln::msgs::DecodeError;
40 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCType, ChannelTransactionParameters, HolderCommitmentTransaction};
41 use ln::channelmanager::HTLCSource;
43 use chain::{BestBlock, WatchedOutput};
44 use chain::chaininterface::{BroadcasterInterface, FeeEstimator, LowerBoundedFeeEstimator};
45 use chain::transaction::{OutPoint, TransactionData};
46 use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
47 use chain::onchaintx::OnchainTxHandler;
48 use chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
50 use util::logger::Logger;
51 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, U48, OptionDeserWrapper};
53 use util::events::Event;
57 use io::{self, Error};
58 use core::convert::TryInto;
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 #[cfg_attr(any(test, fuzzing, feature = "_test_utils"), derive(PartialEq))]
72 pub struct ChannelMonitorUpdate {
73 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
74 /// The sequence number of this update. Updates *must* be replayed in-order according to this
75 /// sequence number (and updates may panic if they are not). The update_id values are strictly
76 /// increasing and increase by one for each new update, with one exception specified below.
78 /// This sequence number is also used to track up to which points updates which returned
79 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
80 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
82 /// The only instance where update_id values are not strictly increasing is the case where we
83 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
84 /// its docs for more details.
89 /// (1) a channel has been force closed and
90 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
91 /// this channel's (the backward link's) broadcasted commitment transaction
92 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
93 /// with the update providing said payment preimage. No other update types are allowed after
95 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
97 impl Writeable for ChannelMonitorUpdate {
98 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
99 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
100 self.update_id.write(w)?;
101 (self.updates.len() as u64).write(w)?;
102 for update_step in self.updates.iter() {
103 update_step.write(w)?;
105 write_tlv_fields!(w, {});
109 impl Readable for ChannelMonitorUpdate {
110 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
111 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
112 let update_id: u64 = Readable::read(r)?;
113 let len: u64 = Readable::read(r)?;
114 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
116 if let Some(upd) = MaybeReadable::read(r)? {
120 read_tlv_fields!(r, {});
121 Ok(Self { update_id, updates })
125 /// An event to be processed by the ChannelManager.
126 #[derive(Clone, PartialEq)]
127 pub enum MonitorEvent {
128 /// A monitor event containing an HTLCUpdate.
129 HTLCEvent(HTLCUpdate),
131 /// A monitor event that the Channel's commitment transaction was confirmed.
132 CommitmentTxConfirmed(OutPoint),
134 /// Indicates a [`ChannelMonitor`] update has completed. See
135 /// [`ChannelMonitorUpdateErr::TemporaryFailure`] for more information on how this is used.
137 /// [`ChannelMonitorUpdateErr::TemporaryFailure`]: super::ChannelMonitorUpdateErr::TemporaryFailure
139 /// The funding outpoint of the [`ChannelMonitor`] that was updated
140 funding_txo: OutPoint,
141 /// The Update ID from [`ChannelMonitorUpdate::update_id`] which was applied or
142 /// [`ChannelMonitor::get_latest_update_id`].
144 /// Note that this should only be set to a given update's ID if all previous updates for the
145 /// same [`ChannelMonitor`] have been applied and persisted.
146 monitor_update_id: u64,
149 /// Indicates a [`ChannelMonitor`] update has failed. See
150 /// [`ChannelMonitorUpdateErr::PermanentFailure`] for more information on how this is used.
152 /// [`ChannelMonitorUpdateErr::PermanentFailure`]: super::ChannelMonitorUpdateErr::PermanentFailure
153 UpdateFailed(OutPoint),
155 impl_writeable_tlv_based_enum_upgradable!(MonitorEvent,
156 // Note that UpdateCompleted and UpdateFailed are currently never serialized to disk as they are
157 // generated only in ChainMonitor
158 (0, UpdateCompleted) => {
159 (0, funding_txo, required),
160 (2, monitor_update_id, required),
164 (4, CommitmentTxConfirmed),
168 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
169 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
170 /// preimage claim backward will lead to loss of funds.
171 #[derive(Clone, PartialEq)]
172 pub struct HTLCUpdate {
173 pub(crate) payment_hash: PaymentHash,
174 pub(crate) payment_preimage: Option<PaymentPreimage>,
175 pub(crate) source: HTLCSource,
176 pub(crate) htlc_value_satoshis: Option<u64>,
178 impl_writeable_tlv_based!(HTLCUpdate, {
179 (0, payment_hash, required),
180 (1, htlc_value_satoshis, option),
181 (2, source, required),
182 (4, payment_preimage, option),
185 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
186 /// instead claiming it in its own individual transaction.
187 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
188 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
189 /// HTLC-Success transaction.
190 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
191 /// transaction confirmed (and we use it in a few more, equivalent, places).
192 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
193 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
194 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
195 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
196 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
197 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
198 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
199 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
200 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
201 /// accurate block height.
202 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
203 /// with at worst this delay, so we are not only using this value as a mercy for them but also
204 /// us as a safeguard to delay with enough time.
205 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
206 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
207 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
210 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
211 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
212 /// by a [`ChannelMonitor`] may be incorrect.
213 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
214 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
215 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
216 // keep bumping another claim tx to solve the outpoint.
217 pub const ANTI_REORG_DELAY: u32 = 6;
218 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
219 /// refuse to accept a new HTLC.
221 /// This is used for a few separate purposes:
222 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
223 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
225 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
226 /// condition with the above), we will fail this HTLC without telling the user we received it,
228 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
229 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
231 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
232 /// in a race condition between the user connecting a block (which would fail it) and the user
233 /// providing us the preimage (which would claim it).
234 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
236 // TODO(devrandom) replace this with HolderCommitmentTransaction
237 #[derive(Clone, PartialEq)]
238 struct HolderSignedTx {
239 /// txid of the transaction in tx, just used to make comparison faster
241 revocation_key: PublicKey,
242 a_htlc_key: PublicKey,
243 b_htlc_key: PublicKey,
244 delayed_payment_key: PublicKey,
245 per_commitment_point: PublicKey,
246 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
247 to_self_value_sat: u64,
250 impl_writeable_tlv_based!(HolderSignedTx, {
252 // Note that this is filled in with data from OnchainTxHandler if it's missing.
253 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
254 (1, to_self_value_sat, (default_value, u64::max_value())),
255 (2, revocation_key, required),
256 (4, a_htlc_key, required),
257 (6, b_htlc_key, required),
258 (8, delayed_payment_key, required),
259 (10, per_commitment_point, required),
260 (12, feerate_per_kw, required),
261 (14, htlc_outputs, vec_type)
264 /// We use this to track static counterparty commitment transaction data and to generate any
265 /// justice or 2nd-stage preimage/timeout transactions.
267 struct CounterpartyCommitmentParameters {
268 counterparty_delayed_payment_base_key: PublicKey,
269 counterparty_htlc_base_key: PublicKey,
270 on_counterparty_tx_csv: u16,
273 impl Writeable for CounterpartyCommitmentParameters {
274 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
275 w.write_all(&byte_utils::be64_to_array(0))?;
276 write_tlv_fields!(w, {
277 (0, self.counterparty_delayed_payment_base_key, required),
278 (2, self.counterparty_htlc_base_key, required),
279 (4, self.on_counterparty_tx_csv, required),
284 impl Readable for CounterpartyCommitmentParameters {
285 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
286 let counterparty_commitment_transaction = {
287 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
288 // used. Read it for compatibility.
289 let per_htlc_len: u64 = Readable::read(r)?;
290 for _ in 0..per_htlc_len {
291 let _txid: Txid = Readable::read(r)?;
292 let htlcs_count: u64 = Readable::read(r)?;
293 for _ in 0..htlcs_count {
294 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
298 let mut counterparty_delayed_payment_base_key = OptionDeserWrapper(None);
299 let mut counterparty_htlc_base_key = OptionDeserWrapper(None);
300 let mut on_counterparty_tx_csv: u16 = 0;
301 read_tlv_fields!(r, {
302 (0, counterparty_delayed_payment_base_key, required),
303 (2, counterparty_htlc_base_key, required),
304 (4, on_counterparty_tx_csv, required),
306 CounterpartyCommitmentParameters {
307 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
308 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
309 on_counterparty_tx_csv,
312 Ok(counterparty_commitment_transaction)
316 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
317 /// transaction causing it.
319 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
321 struct OnchainEventEntry {
325 transaction: Option<Transaction>, // Added as optional, but always filled in, in LDK 0.0.110
328 impl OnchainEventEntry {
329 fn confirmation_threshold(&self) -> u32 {
330 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
332 OnchainEvent::MaturingOutput {
333 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
335 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
336 // it's broadcastable when we see the previous block.
337 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
339 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
340 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
341 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
342 // it's broadcastable when we see the previous block.
343 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
350 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
351 best_block.height() >= self.confirmation_threshold()
355 /// The (output index, sats value) for the counterparty's output in a commitment transaction.
357 /// This was added as an `Option` in 0.0.110.
358 type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
360 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
361 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
364 /// An outbound HTLC failing after a transaction is confirmed. Used
365 /// * when an outbound HTLC output is spent by us after the HTLC timed out
366 /// * an outbound HTLC which was not present in the commitment transaction which appeared
367 /// on-chain (either because it was not fully committed to or it was dust).
368 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
369 /// appearing only as an `HTLCSpendConfirmation`, below.
372 payment_hash: PaymentHash,
373 htlc_value_satoshis: Option<u64>,
374 /// None in the second case, above, ie when there is no relevant output in the commitment
375 /// transaction which appeared on chain.
376 commitment_tx_output_idx: Option<u32>,
378 /// An output waiting on [`ANTI_REORG_DELAY`] confirmations before we hand the user the
379 /// [`SpendableOutputDescriptor`].
381 descriptor: SpendableOutputDescriptor,
383 /// A spend of the funding output, either a commitment transaction or a cooperative closing
385 FundingSpendConfirmation {
386 /// The CSV delay for the output of the funding spend transaction (implying it is a local
387 /// commitment transaction, and this is the delay on the to_self output).
388 on_local_output_csv: Option<u16>,
389 /// If the funding spend transaction was a known remote commitment transaction, we track
390 /// the output index and amount of the counterparty's `to_self` output here.
392 /// This allows us to generate a [`Balance::CounterpartyRevokedOutputClaimable`] for the
393 /// counterparty output.
394 commitment_tx_to_counterparty_output: CommitmentTxCounterpartyOutputInfo,
396 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
397 /// is constructed. This is used when
398 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
399 /// immediately claim the HTLC on the inbound edge and track the resolution here,
400 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
401 /// * an inbound HTLC is claimed by us (with a preimage).
402 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
404 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by an
405 /// HTLC-Success/HTLC-Failure transaction (and is still claimable with a revocation
407 HTLCSpendConfirmation {
408 commitment_tx_output_idx: u32,
409 /// If the claim was made by either party with a preimage, this is filled in
410 preimage: Option<PaymentPreimage>,
411 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
412 /// we set this to the output CSV value which we will have to wait until to spend the
413 /// output (and generate a SpendableOutput event).
414 on_to_local_output_csv: Option<u16>,
418 impl Writeable for OnchainEventEntry {
419 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
420 write_tlv_fields!(writer, {
421 (0, self.txid, required),
422 (1, self.transaction, option),
423 (2, self.height, required),
424 (4, self.event, required),
430 impl MaybeReadable for OnchainEventEntry {
431 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
432 let mut txid = Txid::all_zeros();
433 let mut transaction = None;
435 let mut event = None;
436 read_tlv_fields!(reader, {
438 (1, transaction, option),
439 (2, height, required),
440 (4, event, ignorable),
442 if let Some(ev) = event {
443 Ok(Some(Self { txid, transaction, height, event: ev }))
450 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
452 (0, source, required),
453 (1, htlc_value_satoshis, option),
454 (2, payment_hash, required),
455 (3, commitment_tx_output_idx, option),
457 (1, MaturingOutput) => {
458 (0, descriptor, required),
460 (3, FundingSpendConfirmation) => {
461 (0, on_local_output_csv, option),
462 (1, commitment_tx_to_counterparty_output, option),
464 (5, HTLCSpendConfirmation) => {
465 (0, commitment_tx_output_idx, required),
466 (2, preimage, option),
467 (4, on_to_local_output_csv, option),
472 #[cfg_attr(any(test, fuzzing, feature = "_test_utils"), derive(PartialEq))]
474 pub(crate) enum ChannelMonitorUpdateStep {
475 LatestHolderCommitmentTXInfo {
476 commitment_tx: HolderCommitmentTransaction,
477 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
479 LatestCounterpartyCommitmentTXInfo {
480 commitment_txid: Txid,
481 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
482 commitment_number: u64,
483 their_per_commitment_point: PublicKey,
486 payment_preimage: PaymentPreimage,
492 /// Used to indicate that the no future updates will occur, and likely that the latest holder
493 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
495 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
496 /// think we've fallen behind!
497 should_broadcast: bool,
500 scriptpubkey: Script,
504 impl ChannelMonitorUpdateStep {
505 fn variant_name(&self) -> &'static str {
507 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { .. } => "LatestHolderCommitmentTXInfo",
508 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } => "LatestCounterpartyCommitmentTXInfo",
509 ChannelMonitorUpdateStep::PaymentPreimage { .. } => "PaymentPreimage",
510 ChannelMonitorUpdateStep::CommitmentSecret { .. } => "CommitmentSecret",
511 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => "ChannelForceClosed",
512 ChannelMonitorUpdateStep::ShutdownScript { .. } => "ShutdownScript",
517 impl_writeable_tlv_based_enum_upgradable!(ChannelMonitorUpdateStep,
518 (0, LatestHolderCommitmentTXInfo) => {
519 (0, commitment_tx, required),
520 (2, htlc_outputs, vec_type),
522 (1, LatestCounterpartyCommitmentTXInfo) => {
523 (0, commitment_txid, required),
524 (2, commitment_number, required),
525 (4, their_per_commitment_point, required),
526 (6, htlc_outputs, vec_type),
528 (2, PaymentPreimage) => {
529 (0, payment_preimage, required),
531 (3, CommitmentSecret) => {
533 (2, secret, required),
535 (4, ChannelForceClosed) => {
536 (0, should_broadcast, required),
538 (5, ShutdownScript) => {
539 (0, scriptpubkey, required),
543 /// Details about the balance(s) available for spending once the channel appears on chain.
545 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
547 #[derive(Clone, Debug, PartialEq, Eq)]
548 #[cfg_attr(test, derive(PartialOrd, Ord))]
550 /// The channel is not yet closed (or the commitment or closing transaction has not yet
551 /// appeared in a block). The given balance is claimable (less on-chain fees) if the channel is
552 /// force-closed now.
553 ClaimableOnChannelClose {
554 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
555 /// required to do so.
556 claimable_amount_satoshis: u64,
558 /// The channel has been closed, and the given balance is ours but awaiting confirmations until
559 /// we consider it spendable.
560 ClaimableAwaitingConfirmations {
561 /// The amount available to claim, in satoshis, possibly excluding the on-chain fees which
562 /// were spent in broadcasting the transaction.
563 claimable_amount_satoshis: u64,
564 /// The height at which an [`Event::SpendableOutputs`] event will be generated for this
566 confirmation_height: u32,
568 /// The channel has been closed, and the given balance should be ours but awaiting spending
569 /// transaction confirmation. If the spending transaction does not confirm in time, it is
570 /// possible our counterparty can take the funds by broadcasting an HTLC timeout on-chain.
572 /// Once the spending transaction confirms, before it has reached enough confirmations to be
573 /// considered safe from chain reorganizations, the balance will instead be provided via
574 /// [`Balance::ClaimableAwaitingConfirmations`].
575 ContentiousClaimable {
576 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
577 /// required to do so.
578 claimable_amount_satoshis: u64,
579 /// The height at which the counterparty may be able to claim the balance if we have not
583 /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
584 /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
585 /// likely to be claimed by our counterparty before we do.
586 MaybeClaimableHTLCAwaitingTimeout {
587 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
588 /// required to do so.
589 claimable_amount_satoshis: u64,
590 /// The height at which we will be able to claim the balance if our counterparty has not
592 claimable_height: u32,
594 /// The channel has been closed, and our counterparty broadcasted a revoked commitment
597 /// Thus, we're able to claim all outputs in the commitment transaction, one of which has the
598 /// following amount.
599 CounterpartyRevokedOutputClaimable {
600 /// The amount, in satoshis, of the output which we can claim.
602 /// Note that for outputs from HTLC balances this may be excluding some on-chain fees that
603 /// were already spent.
604 claimable_amount_satoshis: u64,
608 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
610 struct IrrevocablyResolvedHTLC {
611 commitment_tx_output_idx: u32,
612 /// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
613 /// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
615 resolving_txid: Option<Txid>, // Added as optional, but always filled in, in 0.0.110
616 /// Only set if the HTLC claim was ours using a payment preimage
617 payment_preimage: Option<PaymentPreimage>,
620 impl_writeable_tlv_based!(IrrevocablyResolvedHTLC, {
621 (0, commitment_tx_output_idx, required),
622 (1, resolving_txid, option),
623 (2, payment_preimage, option),
626 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
627 /// on-chain transactions to ensure no loss of funds occurs.
629 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
630 /// information and are actively monitoring the chain.
632 /// Pending Events or updated HTLCs which have not yet been read out by
633 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
634 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
635 /// gotten are fully handled before re-serializing the new state.
637 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
638 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
639 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
640 /// returned block hash and the the current chain and then reconnecting blocks to get to the
641 /// best chain) upon deserializing the object!
642 pub struct ChannelMonitor<Signer: Sign> {
644 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
646 inner: Mutex<ChannelMonitorImpl<Signer>>,
649 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
650 latest_update_id: u64,
651 commitment_transaction_number_obscure_factor: u64,
653 destination_script: Script,
654 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
655 counterparty_payment_script: Script,
656 shutdown_script: Option<Script>,
658 channel_keys_id: [u8; 32],
659 holder_revocation_basepoint: PublicKey,
660 funding_info: (OutPoint, Script),
661 current_counterparty_commitment_txid: Option<Txid>,
662 prev_counterparty_commitment_txid: Option<Txid>,
664 counterparty_commitment_params: CounterpartyCommitmentParameters,
665 funding_redeemscript: Script,
666 channel_value_satoshis: u64,
667 // first is the idx of the first of the two per-commitment points
668 their_cur_per_commitment_points: Option<(u64, PublicKey, Option<PublicKey>)>,
670 on_holder_tx_csv: u16,
672 commitment_secrets: CounterpartyCommitmentSecrets,
673 /// The set of outpoints in each counterparty commitment transaction. We always need at least
674 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
675 /// transaction broadcast as we need to be able to construct the witness script in all cases.
676 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
677 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
678 /// Nor can we figure out their commitment numbers without the commitment transaction they are
679 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
680 /// commitment transactions which we find on-chain, mapping them to the commitment number which
681 /// can be used to derive the revocation key and claim the transactions.
682 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
683 /// Cache used to make pruning of payment_preimages faster.
684 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
685 /// counterparty transactions (ie should remain pretty small).
686 /// Serialized to disk but should generally not be sent to Watchtowers.
687 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
689 // We store two holder commitment transactions to avoid any race conditions where we may update
690 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
691 // various monitors for one channel being out of sync, and us broadcasting a holder
692 // transaction for which we have deleted claim information on some watchtowers.
693 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
694 current_holder_commitment_tx: HolderSignedTx,
696 // Used just for ChannelManager to make sure it has the latest channel data during
698 current_counterparty_commitment_number: u64,
699 // Used just for ChannelManager to make sure it has the latest channel data during
701 current_holder_commitment_number: u64,
703 /// The set of payment hashes from inbound payments for which we know the preimage. Payment
704 /// preimages that are not included in any unrevoked local commitment transaction or unrevoked
705 /// remote commitment transactions are automatically removed when commitment transactions are
707 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
709 // Note that `MonitorEvent`s MUST NOT be generated during update processing, only generated
710 // during chain data processing. This prevents a race in `ChainMonitor::update_channel` (and
711 // presumably user implementations thereof as well) where we update the in-memory channel
712 // object, then before the persistence finishes (as it's all under a read-lock), we return
713 // pending events to the user or to the relevant `ChannelManager`. Then, on reload, we'll have
714 // the pre-event state here, but have processed the event in the `ChannelManager`.
715 // Note that because the `event_lock` in `ChainMonitor` is only taken in
716 // block/transaction-connected events and *not* during block/transaction-disconnected events,
717 // we further MUST NOT generate events during block/transaction-disconnection.
718 pending_monitor_events: Vec<MonitorEvent>,
720 pending_events: Vec<Event>,
722 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
723 // which to take actions once they reach enough confirmations. Each entry includes the
724 // transaction's id and the height when the transaction was confirmed on chain.
725 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
727 // If we get serialized out and re-read, we need to make sure that the chain monitoring
728 // interface knows about the TXOs that we want to be notified of spends of. We could probably
729 // be smart and derive them from the above storage fields, but its much simpler and more
730 // Obviously Correct (tm) if we just keep track of them explicitly.
731 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
734 pub onchain_tx_handler: OnchainTxHandler<Signer>,
736 onchain_tx_handler: OnchainTxHandler<Signer>,
738 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
739 // channel has been force-closed. After this is set, no further holder commitment transaction
740 // updates may occur, and we panic!() if one is provided.
741 lockdown_from_offchain: bool,
743 // Set once we've signed a holder commitment transaction and handed it over to our
744 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
745 // may occur, and we fail any such monitor updates.
747 // In case of update rejection due to a locally already signed commitment transaction, we
748 // nevertheless store update content to track in case of concurrent broadcast by another
749 // remote monitor out-of-order with regards to the block view.
750 holder_tx_signed: bool,
752 // If a spend of the funding output is seen, we set this to true and reject any further
753 // updates. This prevents any further changes in the offchain state no matter the order
754 // of block connection between ChannelMonitors and the ChannelManager.
755 funding_spend_seen: bool,
757 funding_spend_confirmed: Option<Txid>,
758 confirmed_commitment_tx_counterparty_output: CommitmentTxCounterpartyOutputInfo,
759 /// The set of HTLCs which have been either claimed or failed on chain and have reached
760 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
761 /// spending CSV for revocable outputs).
762 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
764 // We simply modify best_block in Channel's block_connected so that serialization is
765 // consistent but hopefully the users' copy handles block_connected in a consistent way.
766 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
767 // their best_block from its state and not based on updated copies that didn't run through
768 // the full block_connected).
769 best_block: BestBlock,
771 /// The node_id of our counterparty
772 counterparty_node_id: Option<PublicKey>,
774 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
777 /// Transaction outputs to watch for on-chain spends.
778 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
780 #[cfg(any(test, fuzzing, feature = "_test_utils"))]
781 /// Used only in testing and fuzzing to check serialization roundtrips don't change the underlying
783 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
784 fn eq(&self, other: &Self) -> bool {
785 let inner = self.inner.lock().unwrap();
786 let other = other.inner.lock().unwrap();
791 #[cfg(any(test, fuzzing, feature = "_test_utils"))]
792 /// Used only in testing and fuzzing to check serialization roundtrips don't change the underlying
794 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
795 fn eq(&self, other: &Self) -> bool {
796 if self.latest_update_id != other.latest_update_id ||
797 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
798 self.destination_script != other.destination_script ||
799 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
800 self.counterparty_payment_script != other.counterparty_payment_script ||
801 self.channel_keys_id != other.channel_keys_id ||
802 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
803 self.funding_info != other.funding_info ||
804 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
805 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
806 self.counterparty_commitment_params != other.counterparty_commitment_params ||
807 self.funding_redeemscript != other.funding_redeemscript ||
808 self.channel_value_satoshis != other.channel_value_satoshis ||
809 self.their_cur_per_commitment_points != other.their_cur_per_commitment_points ||
810 self.on_holder_tx_csv != other.on_holder_tx_csv ||
811 self.commitment_secrets != other.commitment_secrets ||
812 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
813 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
814 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
815 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
816 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
817 self.current_holder_commitment_number != other.current_holder_commitment_number ||
818 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
819 self.payment_preimages != other.payment_preimages ||
820 self.pending_monitor_events != other.pending_monitor_events ||
821 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
822 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
823 self.outputs_to_watch != other.outputs_to_watch ||
824 self.lockdown_from_offchain != other.lockdown_from_offchain ||
825 self.holder_tx_signed != other.holder_tx_signed ||
826 self.funding_spend_seen != other.funding_spend_seen ||
827 self.funding_spend_confirmed != other.funding_spend_confirmed ||
828 self.confirmed_commitment_tx_counterparty_output != other.confirmed_commitment_tx_counterparty_output ||
829 self.htlcs_resolved_on_chain != other.htlcs_resolved_on_chain
838 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
839 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
840 self.inner.lock().unwrap().write(writer)
844 // These are also used for ChannelMonitorUpdate, above.
845 const SERIALIZATION_VERSION: u8 = 1;
846 const MIN_SERIALIZATION_VERSION: u8 = 1;
848 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
849 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
850 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
852 self.latest_update_id.write(writer)?;
854 // Set in initial Channel-object creation, so should always be set by now:
855 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
857 self.destination_script.write(writer)?;
858 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
859 writer.write_all(&[0; 1])?;
860 broadcasted_holder_revokable_script.0.write(writer)?;
861 broadcasted_holder_revokable_script.1.write(writer)?;
862 broadcasted_holder_revokable_script.2.write(writer)?;
864 writer.write_all(&[1; 1])?;
867 self.counterparty_payment_script.write(writer)?;
868 match &self.shutdown_script {
869 Some(script) => script.write(writer)?,
870 None => Script::new().write(writer)?,
873 self.channel_keys_id.write(writer)?;
874 self.holder_revocation_basepoint.write(writer)?;
875 writer.write_all(&self.funding_info.0.txid[..])?;
876 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
877 self.funding_info.1.write(writer)?;
878 self.current_counterparty_commitment_txid.write(writer)?;
879 self.prev_counterparty_commitment_txid.write(writer)?;
881 self.counterparty_commitment_params.write(writer)?;
882 self.funding_redeemscript.write(writer)?;
883 self.channel_value_satoshis.write(writer)?;
885 match self.their_cur_per_commitment_points {
886 Some((idx, pubkey, second_option)) => {
887 writer.write_all(&byte_utils::be48_to_array(idx))?;
888 writer.write_all(&pubkey.serialize())?;
889 match second_option {
890 Some(second_pubkey) => {
891 writer.write_all(&second_pubkey.serialize())?;
894 writer.write_all(&[0; 33])?;
899 writer.write_all(&byte_utils::be48_to_array(0))?;
903 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
905 self.commitment_secrets.write(writer)?;
907 macro_rules! serialize_htlc_in_commitment {
908 ($htlc_output: expr) => {
909 writer.write_all(&[$htlc_output.offered as u8; 1])?;
910 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
911 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
912 writer.write_all(&$htlc_output.payment_hash.0[..])?;
913 $htlc_output.transaction_output_index.write(writer)?;
917 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
918 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
919 writer.write_all(&txid[..])?;
920 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
921 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
922 debug_assert!(htlc_source.is_none() || Some(**txid) == self.current_counterparty_commitment_txid
923 || Some(**txid) == self.prev_counterparty_commitment_txid,
924 "HTLC Sources for all revoked commitment transactions should be none!");
925 serialize_htlc_in_commitment!(htlc_output);
926 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
930 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
931 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
932 writer.write_all(&txid[..])?;
933 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
936 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
937 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
938 writer.write_all(&payment_hash.0[..])?;
939 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
942 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
943 writer.write_all(&[1; 1])?;
944 prev_holder_tx.write(writer)?;
946 writer.write_all(&[0; 1])?;
949 self.current_holder_commitment_tx.write(writer)?;
951 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
952 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
954 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
955 for payment_preimage in self.payment_preimages.values() {
956 writer.write_all(&payment_preimage.0[..])?;
959 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
960 MonitorEvent::HTLCEvent(_) => true,
961 MonitorEvent::CommitmentTxConfirmed(_) => true,
963 }).count() as u64).to_be_bytes())?;
964 for event in self.pending_monitor_events.iter() {
966 MonitorEvent::HTLCEvent(upd) => {
970 MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)?,
971 _ => {}, // Covered in the TLV writes below
975 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
976 for event in self.pending_events.iter() {
977 event.write(writer)?;
980 self.best_block.block_hash().write(writer)?;
981 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
983 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
984 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
985 entry.write(writer)?;
988 (self.outputs_to_watch.len() as u64).write(writer)?;
989 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
991 (idx_scripts.len() as u64).write(writer)?;
992 for (idx, script) in idx_scripts.iter() {
994 script.write(writer)?;
997 self.onchain_tx_handler.write(writer)?;
999 self.lockdown_from_offchain.write(writer)?;
1000 self.holder_tx_signed.write(writer)?;
1002 write_tlv_fields!(writer, {
1003 (1, self.funding_spend_confirmed, option),
1004 (3, self.htlcs_resolved_on_chain, vec_type),
1005 (5, self.pending_monitor_events, vec_type),
1006 (7, self.funding_spend_seen, required),
1007 (9, self.counterparty_node_id, option),
1008 (11, self.confirmed_commitment_tx_counterparty_output, option),
1015 impl<Signer: Sign> ChannelMonitor<Signer> {
1016 /// For lockorder enforcement purposes, we need to have a single site which constructs the
1017 /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
1018 /// PartialEq implementation) we may decide a lockorder violation has occurred.
1019 fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
1020 ChannelMonitor { inner: Mutex::new(imp) }
1023 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
1024 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1025 channel_parameters: &ChannelTransactionParameters,
1026 funding_redeemscript: Script, channel_value_satoshis: u64,
1027 commitment_transaction_number_obscure_factor: u64,
1028 initial_holder_commitment_tx: HolderCommitmentTransaction,
1029 best_block: BestBlock, counterparty_node_id: PublicKey) -> ChannelMonitor<Signer> {
1031 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1032 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1033 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1035 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
1036 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
1037 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
1038 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
1040 let channel_keys_id = keys.channel_keys_id();
1041 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1043 // block for Rust 1.34 compat
1044 let (holder_commitment_tx, current_holder_commitment_number) = {
1045 let trusted_tx = initial_holder_commitment_tx.trust();
1046 let txid = trusted_tx.txid();
1048 let tx_keys = trusted_tx.keys();
1049 let holder_commitment_tx = HolderSignedTx {
1051 revocation_key: tx_keys.revocation_key,
1052 a_htlc_key: tx_keys.broadcaster_htlc_key,
1053 b_htlc_key: tx_keys.countersignatory_htlc_key,
1054 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1055 per_commitment_point: tx_keys.per_commitment_point,
1056 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1057 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
1058 feerate_per_kw: trusted_tx.feerate_per_kw(),
1060 (holder_commitment_tx, trusted_tx.commitment_number())
1063 let onchain_tx_handler =
1064 OnchainTxHandler::new(destination_script.clone(), keys,
1065 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
1067 let mut outputs_to_watch = HashMap::new();
1068 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1070 Self::from_impl(ChannelMonitorImpl {
1071 latest_update_id: 0,
1072 commitment_transaction_number_obscure_factor,
1074 destination_script: destination_script.clone(),
1075 broadcasted_holder_revokable_script: None,
1076 counterparty_payment_script,
1080 holder_revocation_basepoint,
1082 current_counterparty_commitment_txid: None,
1083 prev_counterparty_commitment_txid: None,
1085 counterparty_commitment_params,
1086 funding_redeemscript,
1087 channel_value_satoshis,
1088 their_cur_per_commitment_points: None,
1090 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1092 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1093 counterparty_claimable_outpoints: HashMap::new(),
1094 counterparty_commitment_txn_on_chain: HashMap::new(),
1095 counterparty_hash_commitment_number: HashMap::new(),
1097 prev_holder_signed_commitment_tx: None,
1098 current_holder_commitment_tx: holder_commitment_tx,
1099 current_counterparty_commitment_number: 1 << 48,
1100 current_holder_commitment_number,
1102 payment_preimages: HashMap::new(),
1103 pending_monitor_events: Vec::new(),
1104 pending_events: Vec::new(),
1106 onchain_events_awaiting_threshold_conf: Vec::new(),
1111 lockdown_from_offchain: false,
1112 holder_tx_signed: false,
1113 funding_spend_seen: false,
1114 funding_spend_confirmed: None,
1115 confirmed_commitment_tx_counterparty_output: None,
1116 htlcs_resolved_on_chain: Vec::new(),
1119 counterparty_node_id: Some(counterparty_node_id),
1126 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1127 self.inner.lock().unwrap().provide_secret(idx, secret)
1130 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1131 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1132 /// possibly future revocation/preimage information) to claim outputs where possible.
1133 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1134 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1137 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1138 commitment_number: u64,
1139 their_per_commitment_point: PublicKey,
1141 ) where L::Target: Logger {
1142 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1143 txid, htlc_outputs, commitment_number, their_per_commitment_point, logger)
1147 fn provide_latest_holder_commitment_tx(
1148 &self, holder_commitment_tx: HolderCommitmentTransaction,
1149 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1150 ) -> Result<(), ()> {
1151 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(holder_commitment_tx, htlc_outputs).map_err(|_| ())
1154 /// This is used to provide payment preimage(s) out-of-band during startup without updating the
1155 /// off-chain state with a new commitment transaction.
1156 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1158 payment_hash: &PaymentHash,
1159 payment_preimage: &PaymentPreimage,
1161 fee_estimator: &LowerBoundedFeeEstimator<F>,
1164 B::Target: BroadcasterInterface,
1165 F::Target: FeeEstimator,
1168 self.inner.lock().unwrap().provide_payment_preimage(
1169 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1172 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
1177 B::Target: BroadcasterInterface,
1180 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
1183 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1186 /// panics if the given update is not the next update by update_id.
1187 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1189 updates: &ChannelMonitorUpdate,
1195 B::Target: BroadcasterInterface,
1196 F::Target: FeeEstimator,
1199 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1202 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1204 pub fn get_latest_update_id(&self) -> u64 {
1205 self.inner.lock().unwrap().get_latest_update_id()
1208 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1209 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1210 self.inner.lock().unwrap().get_funding_txo().clone()
1213 /// Gets a list of txids, with their output scripts (in the order they appear in the
1214 /// transaction), which we must learn about spends of via block_connected().
1215 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1216 self.inner.lock().unwrap().get_outputs_to_watch()
1217 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1220 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1221 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1222 /// have been registered.
1223 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1224 let lock = self.inner.lock().unwrap();
1225 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1226 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1227 for (index, script_pubkey) in outputs.iter() {
1228 assert!(*index <= u16::max_value() as u32);
1229 filter.register_output(WatchedOutput {
1231 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1232 script_pubkey: script_pubkey.clone(),
1238 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1239 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1240 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1241 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1244 /// Gets the list of pending events which were generated by previous actions, clearing the list
1247 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1248 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1249 /// no internal locking in ChannelMonitors.
1250 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1251 self.inner.lock().unwrap().get_and_clear_pending_events()
1254 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1255 self.inner.lock().unwrap().get_min_seen_secret()
1258 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1259 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1262 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1263 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1266 /// Gets the `node_id` of the counterparty for this channel.
1268 /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
1270 pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
1271 self.inner.lock().unwrap().counterparty_node_id
1274 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1275 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1276 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1277 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1278 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1279 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1280 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1281 /// out-of-band the other node operator to coordinate with him if option is available to you.
1282 /// In any-case, choice is up to the user.
1283 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1284 where L::Target: Logger {
1285 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1288 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1289 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1290 /// revoked commitment transaction.
1291 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1292 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1293 where L::Target: Logger {
1294 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1297 /// Processes transactions in a newly connected block, which may result in any of the following:
1298 /// - update the monitor's state against resolved HTLCs
1299 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1300 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1301 /// - detect settled outputs for later spending
1302 /// - schedule and bump any in-flight claims
1304 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1305 /// [`get_outputs_to_watch`].
1307 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1308 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1310 header: &BlockHeader,
1311 txdata: &TransactionData,
1316 ) -> Vec<TransactionOutputs>
1318 B::Target: BroadcasterInterface,
1319 F::Target: FeeEstimator,
1322 self.inner.lock().unwrap().block_connected(
1323 header, txdata, height, broadcaster, fee_estimator, logger)
1326 /// Determines if the disconnected block contained any transactions of interest and updates
1328 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1330 header: &BlockHeader,
1336 B::Target: BroadcasterInterface,
1337 F::Target: FeeEstimator,
1340 self.inner.lock().unwrap().block_disconnected(
1341 header, height, broadcaster, fee_estimator, logger)
1344 /// Processes transactions confirmed in a block with the given header and height, returning new
1345 /// outputs to watch. See [`block_connected`] for details.
1347 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1348 /// blocks. See [`chain::Confirm`] for calling expectations.
1350 /// [`block_connected`]: Self::block_connected
1351 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1353 header: &BlockHeader,
1354 txdata: &TransactionData,
1359 ) -> Vec<TransactionOutputs>
1361 B::Target: BroadcasterInterface,
1362 F::Target: FeeEstimator,
1365 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1366 self.inner.lock().unwrap().transactions_confirmed(
1367 header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
1370 /// Processes a transaction that was reorganized out of the chain.
1372 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1373 /// than blocks. See [`chain::Confirm`] for calling expectations.
1375 /// [`block_disconnected`]: Self::block_disconnected
1376 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1383 B::Target: BroadcasterInterface,
1384 F::Target: FeeEstimator,
1387 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1388 self.inner.lock().unwrap().transaction_unconfirmed(
1389 txid, broadcaster, &bounded_fee_estimator, logger);
1392 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1393 /// [`block_connected`] for details.
1395 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1396 /// blocks. See [`chain::Confirm`] for calling expectations.
1398 /// [`block_connected`]: Self::block_connected
1399 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1401 header: &BlockHeader,
1406 ) -> Vec<TransactionOutputs>
1408 B::Target: BroadcasterInterface,
1409 F::Target: FeeEstimator,
1412 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1413 self.inner.lock().unwrap().best_block_updated(
1414 header, height, broadcaster, &bounded_fee_estimator, logger)
1417 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1418 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1419 let inner = self.inner.lock().unwrap();
1420 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1422 .map(|entry| entry.txid)
1423 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1425 txids.sort_unstable();
1430 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1431 /// [`chain::Confirm`] interfaces.
1432 pub fn current_best_block(&self) -> BestBlock {
1433 self.inner.lock().unwrap().best_block.clone()
1437 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1438 /// Helper for get_claimable_balances which does the work for an individual HTLC, generating up
1439 /// to one `Balance` for the HTLC.
1440 fn get_htlc_balance(&self, htlc: &HTLCOutputInCommitment, holder_commitment: bool,
1441 counterparty_revoked_commitment: bool, confirmed_txid: Option<Txid>)
1442 -> Option<Balance> {
1443 let htlc_commitment_tx_output_idx =
1444 if let Some(v) = htlc.transaction_output_index { v } else { return None; };
1446 let mut htlc_spend_txid_opt = None;
1447 let mut holder_timeout_spend_pending = None;
1448 let mut htlc_spend_pending = None;
1449 let mut holder_delayed_output_pending = None;
1450 for event in self.onchain_events_awaiting_threshold_conf.iter() {
1452 OnchainEvent::HTLCUpdate { commitment_tx_output_idx, htlc_value_satoshis, .. }
1453 if commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) => {
1454 debug_assert!(htlc_spend_txid_opt.is_none());
1455 htlc_spend_txid_opt = event.transaction.as_ref().map(|tx| tx.txid());
1456 debug_assert!(holder_timeout_spend_pending.is_none());
1457 debug_assert_eq!(htlc_value_satoshis.unwrap(), htlc.amount_msat / 1000);
1458 holder_timeout_spend_pending = Some(event.confirmation_threshold());
1460 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. }
1461 if commitment_tx_output_idx == htlc_commitment_tx_output_idx => {
1462 debug_assert!(htlc_spend_txid_opt.is_none());
1463 htlc_spend_txid_opt = event.transaction.as_ref().map(|tx| tx.txid());
1464 debug_assert!(htlc_spend_pending.is_none());
1465 htlc_spend_pending = Some((event.confirmation_threshold(), preimage.is_some()));
1467 OnchainEvent::MaturingOutput {
1468 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) }
1469 if descriptor.outpoint.index as u32 == htlc_commitment_tx_output_idx => {
1470 debug_assert!(holder_delayed_output_pending.is_none());
1471 holder_delayed_output_pending = Some(event.confirmation_threshold());
1476 let htlc_resolved = self.htlcs_resolved_on_chain.iter()
1477 .find(|v| if v.commitment_tx_output_idx == htlc_commitment_tx_output_idx {
1478 debug_assert!(htlc_spend_txid_opt.is_none());
1479 htlc_spend_txid_opt = v.resolving_txid;
1482 debug_assert!(holder_timeout_spend_pending.is_some() as u8 + htlc_spend_pending.is_some() as u8 + htlc_resolved.is_some() as u8 <= 1);
1484 let htlc_output_to_spend =
1485 if let Some(txid) = htlc_spend_txid_opt {
1487 self.onchain_tx_handler.channel_transaction_parameters.opt_anchors.is_none(),
1488 "This code needs updating for anchors");
1489 BitcoinOutPoint::new(txid, 0)
1491 BitcoinOutPoint::new(confirmed_txid.unwrap(), htlc_commitment_tx_output_idx)
1493 let htlc_output_spend_pending = self.onchain_tx_handler.is_output_spend_pending(&htlc_output_to_spend);
1495 if let Some(conf_thresh) = holder_delayed_output_pending {
1496 debug_assert!(holder_commitment);
1497 return Some(Balance::ClaimableAwaitingConfirmations {
1498 claimable_amount_satoshis: htlc.amount_msat / 1000,
1499 confirmation_height: conf_thresh,
1501 } else if htlc_resolved.is_some() && !htlc_output_spend_pending {
1502 // Funding transaction spends should be fully confirmed by the time any
1503 // HTLC transactions are resolved, unless we're talking about a holder
1504 // commitment tx, whose resolution is delayed until the CSV timeout is
1505 // reached, even though HTLCs may be resolved after only
1506 // ANTI_REORG_DELAY confirmations.
1507 debug_assert!(holder_commitment || self.funding_spend_confirmed.is_some());
1508 } else if counterparty_revoked_commitment {
1509 let htlc_output_claim_pending = self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1510 if let OnchainEvent::MaturingOutput {
1511 descriptor: SpendableOutputDescriptor::StaticOutput { .. }
1513 if event.transaction.as_ref().map(|tx| tx.input.iter().any(|inp| {
1514 if let Some(htlc_spend_txid) = htlc_spend_txid_opt {
1515 Some(tx.txid()) == htlc_spend_txid_opt ||
1516 inp.previous_output.txid == htlc_spend_txid
1518 Some(inp.previous_output.txid) == confirmed_txid &&
1519 inp.previous_output.vout == htlc_commitment_tx_output_idx
1521 })).unwrap_or(false) {
1526 if htlc_output_claim_pending.is_some() {
1527 // We already push `Balance`s onto the `res` list for every
1528 // `StaticOutput` in a `MaturingOutput` in the revoked
1529 // counterparty commitment transaction case generally, so don't
1530 // need to do so again here.
1532 debug_assert!(holder_timeout_spend_pending.is_none(),
1533 "HTLCUpdate OnchainEvents should never appear for preimage claims");
1534 debug_assert!(!htlc.offered || htlc_spend_pending.is_none() || !htlc_spend_pending.unwrap().1,
1535 "We don't (currently) generate preimage claims against revoked outputs, where did you get one?!");
1536 return Some(Balance::CounterpartyRevokedOutputClaimable {
1537 claimable_amount_satoshis: htlc.amount_msat / 1000,
1540 } else if htlc.offered == holder_commitment {
1541 // If the payment was outbound, check if there's an HTLCUpdate
1542 // indicating we have spent this HTLC with a timeout, claiming it back
1543 // and awaiting confirmations on it.
1544 if let Some(conf_thresh) = holder_timeout_spend_pending {
1545 return Some(Balance::ClaimableAwaitingConfirmations {
1546 claimable_amount_satoshis: htlc.amount_msat / 1000,
1547 confirmation_height: conf_thresh,
1550 return Some(Balance::MaybeClaimableHTLCAwaitingTimeout {
1551 claimable_amount_satoshis: htlc.amount_msat / 1000,
1552 claimable_height: htlc.cltv_expiry,
1555 } else if self.payment_preimages.get(&htlc.payment_hash).is_some() {
1556 // Otherwise (the payment was inbound), only expose it as claimable if
1557 // we know the preimage.
1558 // Note that if there is a pending claim, but it did not use the
1559 // preimage, we lost funds to our counterparty! We will then continue
1560 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1561 debug_assert!(holder_timeout_spend_pending.is_none());
1562 if let Some((conf_thresh, true)) = htlc_spend_pending {
1563 return Some(Balance::ClaimableAwaitingConfirmations {
1564 claimable_amount_satoshis: htlc.amount_msat / 1000,
1565 confirmation_height: conf_thresh,
1568 return Some(Balance::ContentiousClaimable {
1569 claimable_amount_satoshis: htlc.amount_msat / 1000,
1570 timeout_height: htlc.cltv_expiry,
1578 impl<Signer: Sign> ChannelMonitor<Signer> {
1579 /// Gets the balances in this channel which are either claimable by us if we were to
1580 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1583 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1584 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1585 /// balance, or until our counterparty has claimed the balance and accrued several
1586 /// confirmations on the claim transaction.
1588 /// Note that for `ChannelMonitors` which track a channel which went on-chain with versions of
1589 /// LDK prior to 0.0.108, balances may not be fully captured if our counterparty broadcasted
1590 /// a revoked state.
1592 /// See [`Balance`] for additional details on the types of claimable balances which
1593 /// may be returned here and their meanings.
1594 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1595 let mut res = Vec::new();
1596 let us = self.inner.lock().unwrap();
1598 let mut confirmed_txid = us.funding_spend_confirmed;
1599 let mut confirmed_counterparty_output = us.confirmed_commitment_tx_counterparty_output;
1600 let mut pending_commitment_tx_conf_thresh = None;
1601 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1602 if let OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } =
1605 confirmed_counterparty_output = commitment_tx_to_counterparty_output;
1606 Some((event.txid, event.confirmation_threshold()))
1609 if let Some((txid, conf_thresh)) = funding_spend_pending {
1610 debug_assert!(us.funding_spend_confirmed.is_none(),
1611 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1612 confirmed_txid = Some(txid);
1613 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1616 macro_rules! walk_htlcs {
1617 ($holder_commitment: expr, $counterparty_revoked_commitment: expr, $htlc_iter: expr) => {
1618 for htlc in $htlc_iter {
1619 if htlc.transaction_output_index.is_some() {
1621 if let Some(bal) = us.get_htlc_balance(htlc, $holder_commitment, $counterparty_revoked_commitment, confirmed_txid) {
1629 if let Some(txid) = confirmed_txid {
1630 let mut found_commitment_tx = false;
1631 if let Some(counterparty_tx_htlcs) = us.counterparty_claimable_outpoints.get(&txid) {
1632 // First look for the to_remote output back to us.
1633 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1634 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1635 if let OnchainEvent::MaturingOutput {
1636 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1638 Some(descriptor.output.value)
1641 res.push(Balance::ClaimableAwaitingConfirmations {
1642 claimable_amount_satoshis: value,
1643 confirmation_height: conf_thresh,
1646 // If a counterparty commitment transaction is awaiting confirmation, we
1647 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1648 // confirmation with the same height or have never met our dust amount.
1651 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1652 walk_htlcs!(false, false, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1654 walk_htlcs!(false, true, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1655 // The counterparty broadcasted a revoked state!
1656 // Look for any StaticOutputs first, generating claimable balances for those.
1657 // If any match the confirmed counterparty revoked to_self output, skip
1658 // generating a CounterpartyRevokedOutputClaimable.
1659 let mut spent_counterparty_output = false;
1660 for event in us.onchain_events_awaiting_threshold_conf.iter() {
1661 if let OnchainEvent::MaturingOutput {
1662 descriptor: SpendableOutputDescriptor::StaticOutput { output, .. }
1664 res.push(Balance::ClaimableAwaitingConfirmations {
1665 claimable_amount_satoshis: output.value,
1666 confirmation_height: event.confirmation_threshold(),
1668 if let Some(confirmed_to_self_idx) = confirmed_counterparty_output.map(|(idx, _)| idx) {
1669 if event.transaction.as_ref().map(|tx|
1670 tx.input.iter().any(|inp| inp.previous_output.vout == confirmed_to_self_idx)
1671 ).unwrap_or(false) {
1672 spent_counterparty_output = true;
1678 if spent_counterparty_output {
1679 } else if let Some((confirmed_to_self_idx, amt)) = confirmed_counterparty_output {
1680 let output_spendable = us.onchain_tx_handler
1681 .is_output_spend_pending(&BitcoinOutPoint::new(txid, confirmed_to_self_idx));
1682 if output_spendable {
1683 res.push(Balance::CounterpartyRevokedOutputClaimable {
1684 claimable_amount_satoshis: amt,
1688 // Counterparty output is missing, either it was broadcasted on a
1689 // previous version of LDK or the counterparty hadn't met dust.
1692 found_commitment_tx = true;
1693 } else if txid == us.current_holder_commitment_tx.txid {
1694 walk_htlcs!(true, false, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1695 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1696 res.push(Balance::ClaimableAwaitingConfirmations {
1697 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1698 confirmation_height: conf_thresh,
1701 found_commitment_tx = true;
1702 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1703 if txid == prev_commitment.txid {
1704 walk_htlcs!(true, false, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1705 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1706 res.push(Balance::ClaimableAwaitingConfirmations {
1707 claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1708 confirmation_height: conf_thresh,
1711 found_commitment_tx = true;
1714 if !found_commitment_tx {
1715 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1716 // We blindly assume this is a cooperative close transaction here, and that
1717 // neither us nor our counterparty misbehaved. At worst we've under-estimated
1718 // the amount we can claim as we'll punish a misbehaving counterparty.
1719 res.push(Balance::ClaimableAwaitingConfirmations {
1720 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1721 confirmation_height: conf_thresh,
1726 let mut claimable_inbound_htlc_value_sat = 0;
1727 for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1728 if htlc.transaction_output_index.is_none() { continue; }
1730 res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
1731 claimable_amount_satoshis: htlc.amount_msat / 1000,
1732 claimable_height: htlc.cltv_expiry,
1734 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1735 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1738 res.push(Balance::ClaimableOnChannelClose {
1739 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1746 /// Gets the set of outbound HTLCs which are pending resolution in this channel.
1747 /// This is used to reconstruct pending outbound payments on restart in the ChannelManager.
1748 pub(crate) fn get_pending_outbound_htlcs(&self) -> HashMap<HTLCSource, HTLCOutputInCommitment> {
1749 let mut res = HashMap::new();
1750 let us = self.inner.lock().unwrap();
1752 macro_rules! walk_htlcs {
1753 ($holder_commitment: expr, $htlc_iter: expr) => {
1754 for (htlc, source) in $htlc_iter {
1755 if us.htlcs_resolved_on_chain.iter().any(|v| Some(v.commitment_tx_output_idx) == htlc.transaction_output_index) {
1756 // We should assert that funding_spend_confirmed is_some() here, but we
1757 // have some unit tests which violate HTLC transaction CSVs entirely and
1759 // TODO: Once tests all connect transactions at consensus-valid times, we
1760 // should assert here like we do in `get_claimable_balances`.
1761 } else if htlc.offered == $holder_commitment {
1762 // If the payment was outbound, check if there's an HTLCUpdate
1763 // indicating we have spent this HTLC with a timeout, claiming it back
1764 // and awaiting confirmations on it.
1765 let htlc_update_confd = us.onchain_events_awaiting_threshold_conf.iter().any(|event| {
1766 if let OnchainEvent::HTLCUpdate { commitment_tx_output_idx: Some(commitment_tx_output_idx), .. } = event.event {
1767 // If the HTLC was timed out, we wait for ANTI_REORG_DELAY blocks
1768 // before considering it "no longer pending" - this matches when we
1769 // provide the ChannelManager an HTLC failure event.
1770 Some(commitment_tx_output_idx) == htlc.transaction_output_index &&
1771 us.best_block.height() >= event.height + ANTI_REORG_DELAY - 1
1772 } else if let OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, .. } = event.event {
1773 // If the HTLC was fulfilled with a preimage, we consider the HTLC
1774 // immediately non-pending, matching when we provide ChannelManager
1776 Some(commitment_tx_output_idx) == htlc.transaction_output_index
1779 if !htlc_update_confd {
1780 res.insert(source.clone(), htlc.clone());
1787 // We're only concerned with the confirmation count of HTLC transactions, and don't
1788 // actually care how many confirmations a commitment transaction may or may not have. Thus,
1789 // we look for either a FundingSpendConfirmation event or a funding_spend_confirmed.
1790 let confirmed_txid = us.funding_spend_confirmed.or_else(|| {
1791 us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1792 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1797 if let Some(txid) = confirmed_txid {
1798 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1799 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().filter_map(|(a, b)| {
1800 if let &Some(ref source) = b {
1801 Some((a, &**source))
1804 } else if txid == us.current_holder_commitment_tx.txid {
1805 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().filter_map(|(a, _, c)| {
1806 if let Some(source) = c { Some((a, source)) } else { None }
1808 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1809 if txid == prev_commitment.txid {
1810 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().filter_map(|(a, _, c)| {
1811 if let Some(source) = c { Some((a, source)) } else { None }
1816 // If we have not seen a commitment transaction on-chain (ie the channel is not yet
1817 // closed), just examine the available counterparty commitment transactions. See docs
1818 // on `fail_unbroadcast_htlcs`, below, for justification.
1819 macro_rules! walk_counterparty_commitment {
1821 if let Some(ref latest_outpoints) = us.counterparty_claimable_outpoints.get($txid) {
1822 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1823 if let &Some(ref source) = source_option {
1824 res.insert((**source).clone(), htlc.clone());
1830 if let Some(ref txid) = us.current_counterparty_commitment_txid {
1831 walk_counterparty_commitment!(txid);
1833 if let Some(ref txid) = us.prev_counterparty_commitment_txid {
1834 walk_counterparty_commitment!(txid);
1841 pub(crate) fn get_stored_preimages(&self) -> HashMap<PaymentHash, PaymentPreimage> {
1842 self.inner.lock().unwrap().payment_preimages.clone()
1846 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
1847 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
1848 /// after ANTI_REORG_DELAY blocks.
1850 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
1851 /// are the commitment transactions which are generated by us. The off-chain state machine in
1852 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
1853 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
1854 /// included in a remote commitment transaction are failed back if they are not present in the
1855 /// broadcasted commitment transaction.
1857 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
1858 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
1859 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
1860 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
1861 macro_rules! fail_unbroadcast_htlcs {
1862 ($self: expr, $commitment_tx_type: expr, $commitment_txid_confirmed: expr, $commitment_tx_confirmed: expr,
1863 $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
1864 debug_assert_eq!($commitment_tx_confirmed.txid(), $commitment_txid_confirmed);
1866 macro_rules! check_htlc_fails {
1867 ($txid: expr, $commitment_tx: expr) => {
1868 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
1869 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1870 if let &Some(ref source) = source_option {
1871 // Check if the HTLC is present in the commitment transaction that was
1872 // broadcast, but not if it was below the dust limit, which we should
1873 // fail backwards immediately as there is no way for us to learn the
1874 // payment_preimage.
1875 // Note that if the dust limit were allowed to change between
1876 // commitment transactions we'd want to be check whether *any*
1877 // broadcastable commitment transaction has the HTLC in it, but it
1878 // cannot currently change after channel initialization, so we don't
1880 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
1882 let mut matched_htlc = false;
1883 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
1884 if broadcast_htlc.transaction_output_index.is_some() &&
1885 (Some(&**source) == *broadcast_source ||
1886 (broadcast_source.is_none() &&
1887 broadcast_htlc.payment_hash == htlc.payment_hash &&
1888 broadcast_htlc.amount_msat == htlc.amount_msat)) {
1889 matched_htlc = true;
1893 if matched_htlc { continue; }
1894 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1895 if entry.height != $commitment_tx_conf_height { return true; }
1897 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1898 *update_source != **source
1903 let entry = OnchainEventEntry {
1904 txid: $commitment_txid_confirmed,
1905 transaction: Some($commitment_tx_confirmed.clone()),
1906 height: $commitment_tx_conf_height,
1907 event: OnchainEvent::HTLCUpdate {
1908 source: (**source).clone(),
1909 payment_hash: htlc.payment_hash.clone(),
1910 htlc_value_satoshis: Some(htlc.amount_msat / 1000),
1911 commitment_tx_output_idx: None,
1914 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction {}, waiting for confirmation (at height {})",
1915 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type,
1916 $commitment_txid_confirmed, entry.confirmation_threshold());
1917 $self.onchain_events_awaiting_threshold_conf.push(entry);
1923 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
1924 check_htlc_fails!(txid, "current");
1926 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
1927 check_htlc_fails!(txid, "previous");
1932 // In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
1933 // witness length match (ie is 136 bytes long). We generate one here which we also use in some
1934 // in-line tests later.
1937 pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
1938 let mut ret = [opcodes::all::OP_NOP.to_u8(); 136];
1939 ret[131] = opcodes::all::OP_DROP.to_u8();
1940 ret[132] = opcodes::all::OP_DROP.to_u8();
1941 ret[133] = opcodes::all::OP_DROP.to_u8();
1942 ret[134] = opcodes::all::OP_DROP.to_u8();
1943 ret[135] = opcodes::OP_TRUE.to_u8();
1948 pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
1949 vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
1952 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1953 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1954 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1955 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1956 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1957 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1958 return Err("Previous secret did not match new one");
1961 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1962 // events for now-revoked/fulfilled HTLCs.
1963 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1964 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1969 if !self.payment_preimages.is_empty() {
1970 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1971 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1972 let min_idx = self.get_min_seen_secret();
1973 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1975 self.payment_preimages.retain(|&k, _| {
1976 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1977 if k == htlc.payment_hash {
1981 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1982 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1983 if k == htlc.payment_hash {
1988 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1995 counterparty_hash_commitment_number.remove(&k);
2004 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 {
2005 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
2006 // so that a remote monitor doesn't learn anything unless there is a malicious close.
2007 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
2009 for &(ref htlc, _) in &htlc_outputs {
2010 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
2013 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
2014 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
2015 self.current_counterparty_commitment_txid = Some(txid);
2016 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
2017 self.current_counterparty_commitment_number = commitment_number;
2018 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
2019 match self.their_cur_per_commitment_points {
2020 Some(old_points) => {
2021 if old_points.0 == commitment_number + 1 {
2022 self.their_cur_per_commitment_points = Some((old_points.0, old_points.1, Some(their_per_commitment_point)));
2023 } else if old_points.0 == commitment_number + 2 {
2024 if let Some(old_second_point) = old_points.2 {
2025 self.their_cur_per_commitment_points = Some((old_points.0 - 1, old_second_point, Some(their_per_commitment_point)));
2027 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2030 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2034 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2037 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
2038 for htlc in htlc_outputs {
2039 if htlc.0.transaction_output_index.is_some() {
2045 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
2046 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
2047 /// is important that any clones of this channel monitor (including remote clones) by kept
2048 /// up-to-date as our holder commitment transaction is updated.
2049 /// Panics if set_on_holder_tx_csv has never been called.
2050 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), &'static str> {
2051 // block for Rust 1.34 compat
2052 let mut new_holder_commitment_tx = {
2053 let trusted_tx = holder_commitment_tx.trust();
2054 let txid = trusted_tx.txid();
2055 let tx_keys = trusted_tx.keys();
2056 self.current_holder_commitment_number = trusted_tx.commitment_number();
2059 revocation_key: tx_keys.revocation_key,
2060 a_htlc_key: tx_keys.broadcaster_htlc_key,
2061 b_htlc_key: tx_keys.countersignatory_htlc_key,
2062 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
2063 per_commitment_point: tx_keys.per_commitment_point,
2065 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
2066 feerate_per_kw: trusted_tx.feerate_per_kw(),
2069 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
2070 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
2071 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
2072 if self.holder_tx_signed {
2073 return Err("Latest holder commitment signed has already been signed, update is rejected");
2078 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
2079 /// commitment_tx_infos which contain the payment hash have been revoked.
2080 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
2081 &mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B,
2082 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
2083 where B::Target: BroadcasterInterface,
2084 F::Target: FeeEstimator,
2087 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
2089 // If the channel is force closed, try to claim the output from this preimage.
2090 // First check if a counterparty commitment transaction has been broadcasted:
2091 macro_rules! claim_htlcs {
2092 ($commitment_number: expr, $txid: expr) => {
2093 let (htlc_claim_reqs, _) = self.get_counterparty_output_claim_info($commitment_number, $txid, None);
2094 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2097 if let Some(txid) = self.current_counterparty_commitment_txid {
2098 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2099 claim_htlcs!(*commitment_number, txid);
2103 if let Some(txid) = self.prev_counterparty_commitment_txid {
2104 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2105 claim_htlcs!(*commitment_number, txid);
2110 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
2111 // claiming the HTLC output from each of the holder commitment transactions.
2112 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
2113 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
2114 // holder commitment transactions.
2115 if self.broadcasted_holder_revokable_script.is_some() {
2116 // Assume that the broadcasted commitment transaction confirmed in the current best
2117 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
2119 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2120 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2121 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
2122 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
2123 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2128 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
2129 where B::Target: BroadcasterInterface,
2132 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
2133 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
2134 broadcaster.broadcast_transaction(tx);
2136 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2139 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: F, logger: &L) -> Result<(), ()>
2140 where B::Target: BroadcasterInterface,
2141 F::Target: FeeEstimator,
2144 log_info!(logger, "Applying update to monitor {}, bringing update_id from {} to {} with {} changes.",
2145 log_funding_info!(self), self.latest_update_id, updates.update_id, updates.updates.len());
2146 // ChannelMonitor updates may be applied after force close if we receive a
2147 // preimage for a broadcasted commitment transaction HTLC output that we'd
2148 // like to claim on-chain. If this is the case, we no longer have guaranteed
2149 // access to the monitor's update ID, so we use a sentinel value instead.
2150 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2151 assert_eq!(updates.updates.len(), 1);
2152 match updates.updates[0] {
2153 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
2155 log_error!(logger, "Attempted to apply post-force-close ChannelMonitorUpdate of type {}", updates.updates[0].variant_name());
2156 panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage");
2159 } else if self.latest_update_id + 1 != updates.update_id {
2160 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
2162 let mut ret = Ok(());
2163 for update in updates.updates.iter() {
2165 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
2166 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
2167 if self.lockdown_from_offchain { panic!(); }
2168 if let Err(e) = self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone()) {
2169 log_error!(logger, "Providing latest holder commitment transaction failed/was refused:");
2170 log_error!(logger, " {}", e);
2174 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_per_commitment_point } => {
2175 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
2176 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_per_commitment_point, logger)
2178 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
2179 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
2180 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&*fee_estimator);
2181 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, &bounded_fee_estimator, logger)
2183 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
2184 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
2185 if let Err(e) = self.provide_secret(*idx, *secret) {
2186 log_error!(logger, "Providing latest counterparty commitment secret failed/was refused:");
2187 log_error!(logger, " {}", e);
2191 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
2192 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
2193 self.lockdown_from_offchain = true;
2194 if *should_broadcast {
2195 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
2196 } else if !self.holder_tx_signed {
2197 log_error!(logger, "You have a toxic holder commitment transaction avaible in channel monitor, read comment in ChannelMonitor::get_latest_holder_commitment_txn to be informed of manual action to take");
2199 // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
2200 // will still give us a ChannelForceClosed event with !should_broadcast, but we
2201 // shouldn't print the scary warning above.
2202 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
2205 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
2206 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
2207 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
2208 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
2213 self.latest_update_id = updates.update_id;
2215 if ret.is_ok() && self.funding_spend_seen {
2216 log_error!(logger, "Refusing Channel Monitor Update as counterparty attempted to update commitment after funding was spent");
2221 pub fn get_latest_update_id(&self) -> u64 {
2222 self.latest_update_id
2225 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
2229 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
2230 // If we've detected a counterparty commitment tx on chain, we must include it in the set
2231 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
2232 // its trivial to do, double-check that here.
2233 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
2234 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
2236 &self.outputs_to_watch
2239 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
2240 let mut ret = Vec::new();
2241 mem::swap(&mut ret, &mut self.pending_monitor_events);
2245 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
2246 let mut ret = Vec::new();
2247 mem::swap(&mut ret, &mut self.pending_events);
2251 /// Can only fail if idx is < get_min_seen_secret
2252 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
2253 self.commitment_secrets.get_secret(idx)
2256 pub(crate) fn get_min_seen_secret(&self) -> u64 {
2257 self.commitment_secrets.get_min_seen_secret()
2260 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
2261 self.current_counterparty_commitment_number
2264 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
2265 self.current_holder_commitment_number
2268 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
2269 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
2270 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
2271 /// HTLC-Success/HTLC-Timeout transactions.
2273 /// Returns packages to claim the revoked output(s), as well as additional outputs to watch and
2274 /// general information about the output that is to the counterparty in the commitment
2276 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L)
2277 -> (Vec<PackageTemplate>, TransactionOutputs, CommitmentTxCounterpartyOutputInfo)
2278 where L::Target: Logger {
2279 // Most secp and related errors trying to create keys means we have no hope of constructing
2280 // a spend transaction...so we return no transactions to broadcast
2281 let mut claimable_outpoints = Vec::new();
2282 let mut watch_outputs = Vec::new();
2283 let mut to_counterparty_output_info = None;
2285 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
2286 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
2288 macro_rules! ignore_error {
2289 ( $thing : expr ) => {
2292 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2297 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);
2298 if commitment_number >= self.get_min_seen_secret() {
2299 let secret = self.get_secret(commitment_number).unwrap();
2300 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2301 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
2302 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
2303 let delayed_key = ignore_error!(chan_utils::derive_public_key(&self.secp_ctx, &PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key), &self.counterparty_commitment_params.counterparty_delayed_payment_base_key));
2305 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
2306 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
2308 // First, process non-htlc outputs (to_holder & to_counterparty)
2309 for (idx, outp) in tx.output.iter().enumerate() {
2310 if outp.script_pubkey == revokeable_p2wsh {
2311 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);
2312 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, true, height);
2313 claimable_outpoints.push(justice_package);
2314 to_counterparty_output_info =
2315 Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value));
2319 // Then, try to find revoked htlc outputs
2320 if let Some(ref per_commitment_data) = per_commitment_option {
2321 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
2322 if let Some(transaction_output_index) = htlc.transaction_output_index {
2323 if transaction_output_index as usize >= tx.output.len() ||
2324 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2325 // per_commitment_data is corrupt or our commitment signing key leaked!
2326 return (claimable_outpoints, (commitment_txid, watch_outputs),
2327 to_counterparty_output_info);
2329 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.opt_anchors.is_some());
2330 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
2331 claimable_outpoints.push(justice_package);
2336 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
2337 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
2338 // We're definitely a counterparty commitment transaction!
2339 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
2340 for (idx, outp) in tx.output.iter().enumerate() {
2341 watch_outputs.push((idx as u32, outp.clone()));
2343 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2345 if let Some(per_commitment_data) = per_commitment_option {
2346 fail_unbroadcast_htlcs!(self, "revoked_counterparty", commitment_txid, tx, height,
2347 per_commitment_data.iter().map(|(htlc, htlc_source)|
2348 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2351 debug_assert!(false, "We should have per-commitment option for any recognized old commitment txn");
2352 fail_unbroadcast_htlcs!(self, "revoked counterparty", commitment_txid, tx, height,
2353 [].iter().map(|reference| *reference), logger);
2356 } else if let Some(per_commitment_data) = per_commitment_option {
2357 // While this isn't useful yet, there is a potential race where if a counterparty
2358 // revokes a state at the same time as the commitment transaction for that state is
2359 // confirmed, and the watchtower receives the block before the user, the user could
2360 // upload a new ChannelMonitor with the revocation secret but the watchtower has
2361 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
2362 // not being generated by the above conditional. Thus, to be safe, we go ahead and
2364 for (idx, outp) in tx.output.iter().enumerate() {
2365 watch_outputs.push((idx as u32, outp.clone()));
2367 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2369 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
2370 fail_unbroadcast_htlcs!(self, "counterparty", commitment_txid, tx, height,
2371 per_commitment_data.iter().map(|(htlc, htlc_source)|
2372 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2375 let (htlc_claim_reqs, counterparty_output_info) =
2376 self.get_counterparty_output_claim_info(commitment_number, commitment_txid, Some(tx));
2377 to_counterparty_output_info = counterparty_output_info;
2378 for req in htlc_claim_reqs {
2379 claimable_outpoints.push(req);
2383 (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2386 /// Returns the HTLC claim package templates and the counterparty output info
2387 fn get_counterparty_output_claim_info(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>)
2388 -> (Vec<PackageTemplate>, CommitmentTxCounterpartyOutputInfo) {
2389 let mut claimable_outpoints = Vec::new();
2390 let mut to_counterparty_output_info: CommitmentTxCounterpartyOutputInfo = None;
2392 let htlc_outputs = match self.counterparty_claimable_outpoints.get(&commitment_txid) {
2393 Some(outputs) => outputs,
2394 None => return (claimable_outpoints, to_counterparty_output_info),
2396 let per_commitment_points = match self.their_cur_per_commitment_points {
2397 Some(points) => points,
2398 None => return (claimable_outpoints, to_counterparty_output_info),
2401 let per_commitment_point =
2402 // If the counterparty commitment tx is the latest valid state, use their latest
2403 // per-commitment point
2404 if per_commitment_points.0 == commitment_number { &per_commitment_points.1 }
2405 else if let Some(point) = per_commitment_points.2.as_ref() {
2406 // If counterparty commitment tx is the state previous to the latest valid state, use
2407 // their previous per-commitment point (non-atomicity of revocation means it's valid for
2408 // them to temporarily have two valid commitment txns from our viewpoint)
2409 if per_commitment_points.0 == commitment_number + 1 {
2411 } else { return (claimable_outpoints, to_counterparty_output_info); }
2412 } else { return (claimable_outpoints, to_counterparty_output_info); };
2414 if let Some(transaction) = tx {
2415 let revokeable_p2wsh_opt =
2416 if let Ok(revocation_pubkey) = chan_utils::derive_public_revocation_key(
2417 &self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint)
2419 if let Ok(delayed_key) = chan_utils::derive_public_key(&self.secp_ctx,
2420 &per_commitment_point,
2421 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key)
2423 Some(chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
2424 self.counterparty_commitment_params.on_counterparty_tx_csv,
2425 &delayed_key).to_v0_p2wsh())
2427 debug_assert!(false, "Failed to derive a delayed payment key for a commitment state we accepted");
2431 debug_assert!(false, "Failed to derive a revocation pubkey key for a commitment state we accepted");
2434 if let Some(revokeable_p2wsh) = revokeable_p2wsh_opt {
2435 for (idx, outp) in transaction.output.iter().enumerate() {
2436 if outp.script_pubkey == revokeable_p2wsh {
2437 to_counterparty_output_info =
2438 Some((idx.try_into().expect("Can't have > 2^32 outputs"), outp.value));
2444 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
2445 if let Some(transaction_output_index) = htlc.transaction_output_index {
2446 if let Some(transaction) = tx {
2447 if transaction_output_index as usize >= transaction.output.len() ||
2448 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2449 // per_commitment_data is corrupt or our commitment signing key leaked!
2450 return (claimable_outpoints, to_counterparty_output_info);
2453 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
2454 if preimage.is_some() || !htlc.offered {
2455 let counterparty_htlc_outp = if htlc.offered {
2456 PackageSolvingData::CounterpartyOfferedHTLCOutput(
2457 CounterpartyOfferedHTLCOutput::build(*per_commitment_point,
2458 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2459 self.counterparty_commitment_params.counterparty_htlc_base_key,
2460 preimage.unwrap(), htlc.clone()))
2462 PackageSolvingData::CounterpartyReceivedHTLCOutput(
2463 CounterpartyReceivedHTLCOutput::build(*per_commitment_point,
2464 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2465 self.counterparty_commitment_params.counterparty_htlc_base_key,
2468 let aggregation = if !htlc.offered { false } else { true };
2469 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
2470 claimable_outpoints.push(counterparty_package);
2475 (claimable_outpoints, to_counterparty_output_info)
2478 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2479 fn check_spend_counterparty_htlc<L: Deref>(&mut self, tx: &Transaction, commitment_number: u64, height: u32, logger: &L) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
2480 let htlc_txid = tx.txid();
2481 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
2482 return (Vec::new(), None)
2485 macro_rules! ignore_error {
2486 ( $thing : expr ) => {
2489 Err(_) => return (Vec::new(), None)
2494 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2495 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2496 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
2498 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, 0);
2499 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, tx.output[0].value, self.counterparty_commitment_params.on_counterparty_tx_csv);
2500 let justice_package = PackageTemplate::build_package(htlc_txid, 0, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, true, height);
2501 let claimable_outpoints = vec!(justice_package);
2502 let outputs = vec![(0, tx.output[0].clone())];
2503 (claimable_outpoints, Some((htlc_txid, outputs)))
2506 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
2507 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2508 // script so we can detect whether a holder transaction has been seen on-chain.
2509 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2510 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2512 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2513 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2515 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2516 if let Some(transaction_output_index) = htlc.transaction_output_index {
2517 let htlc_output = if htlc.offered {
2518 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
2520 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2523 // We can't build an HTLC-Success transaction without the preimage
2526 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
2528 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), htlc.cltv_expiry, false, conf_height);
2529 claim_requests.push(htlc_package);
2533 (claim_requests, broadcasted_holder_revokable_script)
2536 // Returns holder HTLC outputs to watch and react to in case of spending.
2537 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2538 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2539 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2540 if let Some(transaction_output_index) = htlc.transaction_output_index {
2541 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2547 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2548 /// revoked using data in holder_claimable_outpoints.
2549 /// Should not be used if check_spend_revoked_transaction succeeds.
2550 /// Returns None unless the transaction is definitely one of our commitment transactions.
2551 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
2552 let commitment_txid = tx.txid();
2553 let mut claim_requests = Vec::new();
2554 let mut watch_outputs = Vec::new();
2556 macro_rules! append_onchain_update {
2557 ($updates: expr, $to_watch: expr) => {
2558 claim_requests = $updates.0;
2559 self.broadcasted_holder_revokable_script = $updates.1;
2560 watch_outputs.append(&mut $to_watch);
2564 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2565 let mut is_holder_tx = false;
2567 if self.current_holder_commitment_tx.txid == commitment_txid {
2568 is_holder_tx = true;
2569 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2570 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2571 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2572 append_onchain_update!(res, to_watch);
2573 fail_unbroadcast_htlcs!(self, "latest holder", commitment_txid, tx, height,
2574 self.current_holder_commitment_tx.htlc_outputs.iter()
2575 .map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())), logger);
2576 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2577 if holder_tx.txid == commitment_txid {
2578 is_holder_tx = true;
2579 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2580 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2581 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2582 append_onchain_update!(res, to_watch);
2583 fail_unbroadcast_htlcs!(self, "previous holder", commitment_txid, tx, height,
2584 holder_tx.htlc_outputs.iter().map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())),
2590 Some((claim_requests, (commitment_txid, watch_outputs)))
2596 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2597 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2598 self.holder_tx_signed = true;
2599 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2600 let txid = commitment_tx.txid();
2601 let mut holder_transactions = vec![commitment_tx];
2602 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2603 if let Some(vout) = htlc.0.transaction_output_index {
2604 let preimage = if !htlc.0.offered {
2605 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2606 // We can't build an HTLC-Success transaction without the preimage
2609 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2610 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2611 // current locktime requirements on-chain. We will broadcast them in
2612 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2613 // Note that we add + 1 as transactions are broadcastable when they can be
2614 // confirmed in the next block.
2617 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2618 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2619 holder_transactions.push(htlc_tx);
2623 // 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.
2624 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2628 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2629 /// Note that this includes possibly-locktimed-in-the-future transactions!
2630 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2631 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2632 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2633 let txid = commitment_tx.txid();
2634 let mut holder_transactions = vec![commitment_tx];
2635 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2636 if let Some(vout) = htlc.0.transaction_output_index {
2637 let preimage = if !htlc.0.offered {
2638 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2639 // We can't build an HTLC-Success transaction without the preimage
2643 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
2644 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2645 holder_transactions.push(htlc_tx);
2652 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>
2653 where B::Target: BroadcasterInterface,
2654 F::Target: FeeEstimator,
2657 let block_hash = header.block_hash();
2658 self.best_block = BestBlock::new(block_hash, height);
2660 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
2661 self.transactions_confirmed(header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
2664 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
2666 header: &BlockHeader,
2669 fee_estimator: &LowerBoundedFeeEstimator<F>,
2671 ) -> Vec<TransactionOutputs>
2673 B::Target: BroadcasterInterface,
2674 F::Target: FeeEstimator,
2677 let block_hash = header.block_hash();
2679 if height > self.best_block.height() {
2680 self.best_block = BestBlock::new(block_hash, height);
2681 self.block_confirmed(height, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
2682 } else if block_hash != self.best_block.block_hash() {
2683 self.best_block = BestBlock::new(block_hash, height);
2684 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
2685 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
2687 } else { Vec::new() }
2690 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
2692 header: &BlockHeader,
2693 txdata: &TransactionData,
2696 fee_estimator: &LowerBoundedFeeEstimator<F>,
2698 ) -> Vec<TransactionOutputs>
2700 B::Target: BroadcasterInterface,
2701 F::Target: FeeEstimator,
2704 let txn_matched = self.filter_block(txdata);
2705 for tx in &txn_matched {
2706 let mut output_val = 0;
2707 for out in tx.output.iter() {
2708 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2709 output_val += out.value;
2710 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2714 let block_hash = header.block_hash();
2716 let mut watch_outputs = Vec::new();
2717 let mut claimable_outpoints = Vec::new();
2718 for tx in &txn_matched {
2719 if tx.input.len() == 1 {
2720 // Assuming our keys were not leaked (in which case we're screwed no matter what),
2721 // commitment transactions and HTLC transactions will all only ever have one input,
2722 // which is an easy way to filter out any potential non-matching txn for lazy
2724 let prevout = &tx.input[0].previous_output;
2725 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
2726 let mut balance_spendable_csv = None;
2727 log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
2728 log_bytes!(self.funding_info.0.to_channel_id()), tx.txid());
2729 self.funding_spend_seen = true;
2730 let mut commitment_tx_to_counterparty_output = None;
2731 if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
2732 let (mut new_outpoints, new_outputs, counterparty_output_idx_sats) =
2733 self.check_spend_counterparty_transaction(&tx, height, &logger);
2734 commitment_tx_to_counterparty_output = counterparty_output_idx_sats;
2735 if !new_outputs.1.is_empty() {
2736 watch_outputs.push(new_outputs);
2738 claimable_outpoints.append(&mut new_outpoints);
2739 if new_outpoints.is_empty() {
2740 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &logger) {
2741 debug_assert!(commitment_tx_to_counterparty_output.is_none(),
2742 "A commitment transaction matched as both a counterparty and local commitment tx?");
2743 if !new_outputs.1.is_empty() {
2744 watch_outputs.push(new_outputs);
2746 claimable_outpoints.append(&mut new_outpoints);
2747 balance_spendable_csv = Some(self.on_holder_tx_csv);
2751 let txid = tx.txid();
2752 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2754 transaction: Some((*tx).clone()),
2756 event: OnchainEvent::FundingSpendConfirmation {
2757 on_local_output_csv: balance_spendable_csv,
2758 commitment_tx_to_counterparty_output,
2762 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
2763 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
2764 claimable_outpoints.append(&mut new_outpoints);
2765 if let Some(new_outputs) = new_outputs_option {
2766 watch_outputs.push(new_outputs);
2771 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2772 // can also be resolved in a few other ways which can have more than one output. Thus,
2773 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2774 self.is_resolving_htlc_output(&tx, height, &logger);
2776 self.is_paying_spendable_output(&tx, height, &logger);
2779 if height > self.best_block.height() {
2780 self.best_block = BestBlock::new(block_hash, height);
2783 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
2786 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
2787 /// `self.best_block` before calling if a new best blockchain tip is available. More
2788 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
2789 /// complexity especially in `OnchainTx::update_claims_view`.
2791 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
2792 /// confirmed at, even if it is not the current best height.
2793 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
2796 txn_matched: Vec<&Transaction>,
2797 mut watch_outputs: Vec<TransactionOutputs>,
2798 mut claimable_outpoints: Vec<PackageTemplate>,
2800 fee_estimator: &LowerBoundedFeeEstimator<F>,
2802 ) -> Vec<TransactionOutputs>
2804 B::Target: BroadcasterInterface,
2805 F::Target: FeeEstimator,
2808 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
2809 debug_assert!(self.best_block.height() >= conf_height);
2811 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
2812 if should_broadcast {
2813 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2814 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(), false, self.best_block.height());
2815 claimable_outpoints.push(commitment_package);
2816 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2817 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2818 self.holder_tx_signed = true;
2819 // Because we're broadcasting a commitment transaction, we should construct the package
2820 // assuming it gets confirmed in the next block. Sadly, we have code which considers
2821 // "not yet confirmed" things as discardable, so we cannot do that here.
2822 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2823 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2824 if !new_outputs.is_empty() {
2825 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2827 claimable_outpoints.append(&mut new_outpoints);
2830 // Find which on-chain events have reached their confirmation threshold.
2831 let onchain_events_awaiting_threshold_conf =
2832 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2833 let mut onchain_events_reaching_threshold_conf = Vec::new();
2834 for entry in onchain_events_awaiting_threshold_conf {
2835 if entry.has_reached_confirmation_threshold(&self.best_block) {
2836 onchain_events_reaching_threshold_conf.push(entry);
2838 self.onchain_events_awaiting_threshold_conf.push(entry);
2842 // Used to check for duplicate HTLC resolutions.
2843 #[cfg(debug_assertions)]
2844 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2846 .filter_map(|entry| match &entry.event {
2847 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2851 #[cfg(debug_assertions)]
2852 let mut matured_htlcs = Vec::new();
2854 // Produce actionable events from on-chain events having reached their threshold.
2855 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2857 OnchainEvent::HTLCUpdate { ref source, payment_hash, htlc_value_satoshis, commitment_tx_output_idx } => {
2858 // Check for duplicate HTLC resolutions.
2859 #[cfg(debug_assertions)]
2862 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2863 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2864 call either transaction_unconfirmed for the conflicting transaction \
2865 or block_disconnected for a block containing it.");
2867 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2868 "A matured HTLC transaction conflicts with a maturing one; failed to \
2869 call either transaction_unconfirmed for the conflicting transaction \
2870 or block_disconnected for a block containing it.");
2871 matured_htlcs.push(source.clone());
2874 log_debug!(logger, "HTLC {} failure update in {} has got enough confirmations to be passed upstream",
2875 log_bytes!(payment_hash.0), entry.txid);
2876 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2878 payment_preimage: None,
2879 source: source.clone(),
2880 htlc_value_satoshis,
2882 if let Some(idx) = commitment_tx_output_idx {
2883 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
2884 commitment_tx_output_idx: idx, resolving_txid: Some(entry.txid),
2885 payment_preimage: None,
2889 OnchainEvent::MaturingOutput { descriptor } => {
2890 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2891 self.pending_events.push(Event::SpendableOutputs {
2892 outputs: vec![descriptor]
2895 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
2896 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
2897 commitment_tx_output_idx, resolving_txid: Some(entry.txid),
2898 payment_preimage: preimage,
2901 OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } => {
2902 self.funding_spend_confirmed = Some(entry.txid);
2903 self.confirmed_commitment_tx_counterparty_output = commitment_tx_to_counterparty_output;
2908 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
2910 // Determine new outputs to watch by comparing against previously known outputs to watch,
2911 // updating the latter in the process.
2912 watch_outputs.retain(|&(ref txid, ref txouts)| {
2913 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2914 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2918 // If we see a transaction for which we registered outputs previously,
2919 // make sure the registered scriptpubkey at the expected index match
2920 // the actual transaction output one. We failed this case before #653.
2921 for tx in &txn_matched {
2922 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2923 for idx_and_script in outputs.iter() {
2924 assert!((idx_and_script.0 as usize) < tx.output.len());
2925 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2933 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2934 where B::Target: BroadcasterInterface,
2935 F::Target: FeeEstimator,
2938 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2941 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2942 //- maturing spendable output has transaction paying us has been disconnected
2943 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2945 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
2946 self.onchain_tx_handler.block_disconnected(height, broadcaster, &bounded_fee_estimator, logger);
2948 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2951 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2955 fee_estimator: &LowerBoundedFeeEstimator<F>,
2958 B::Target: BroadcasterInterface,
2959 F::Target: FeeEstimator,
2962 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| if entry.txid == *txid {
2963 log_info!(logger, "Removing onchain event with txid {}", txid);
2966 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2969 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2970 /// transactions thereof.
2971 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2972 let mut matched_txn = HashSet::new();
2973 txdata.iter().filter(|&&(_, tx)| {
2974 let mut matches = self.spends_watched_output(tx);
2975 for input in tx.input.iter() {
2976 if matches { break; }
2977 if matched_txn.contains(&input.previous_output.txid) {
2982 matched_txn.insert(tx.txid());
2985 }).map(|(_, tx)| *tx).collect()
2988 /// Checks if a given transaction spends any watched outputs.
2989 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2990 for input in tx.input.iter() {
2991 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2992 for (idx, _script_pubkey) in outputs.iter() {
2993 if *idx == input.previous_output.vout {
2996 // If the expected script is a known type, check that the witness
2997 // appears to be spending the correct type (ie that the match would
2998 // actually succeed in BIP 158/159-style filters).
2999 if _script_pubkey.is_v0_p2wsh() {
3000 if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
3001 // In at least one test we use a deliberately bogus witness
3002 // script which hit an old panic. Thus, we check for that here
3003 // and avoid the assert if its the expected bogus script.
3007 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
3008 } else if _script_pubkey.is_v0_p2wpkh() {
3009 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
3010 } else { panic!(); }
3021 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
3022 // We need to consider all HTLCs which are:
3023 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
3024 // transactions and we'd end up in a race, or
3025 // * are in our latest holder commitment transaction, as this is the thing we will
3026 // broadcast if we go on-chain.
3027 // Note that we consider HTLCs which were below dust threshold here - while they don't
3028 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
3029 // to the source, and if we don't fail the channel we will have to ensure that the next
3030 // updates that peer sends us are update_fails, failing the channel if not. It's probably
3031 // easier to just fail the channel as this case should be rare enough anyway.
3032 let height = self.best_block.height();
3033 macro_rules! scan_commitment {
3034 ($htlcs: expr, $holder_tx: expr) => {
3035 for ref htlc in $htlcs {
3036 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
3037 // chain with enough room to claim the HTLC without our counterparty being able to
3038 // time out the HTLC first.
3039 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
3040 // concern is being able to claim the corresponding inbound HTLC (on another
3041 // channel) before it expires. In fact, we don't even really care if our
3042 // counterparty here claims such an outbound HTLC after it expired as long as we
3043 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
3044 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
3045 // we give ourselves a few blocks of headroom after expiration before going
3046 // on-chain for an expired HTLC.
3047 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
3048 // from us until we've reached the point where we go on-chain with the
3049 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
3050 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
3051 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
3052 // inbound_cltv == height + CLTV_CLAIM_BUFFER
3053 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
3054 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
3055 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
3056 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
3057 // The final, above, condition is checked for statically in channelmanager
3058 // with CHECK_CLTV_EXPIRY_SANITY_2.
3059 let htlc_outbound = $holder_tx == htlc.offered;
3060 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
3061 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
3062 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
3069 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
3071 if let Some(ref txid) = self.current_counterparty_commitment_txid {
3072 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3073 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3076 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
3077 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3078 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3085 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
3086 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
3087 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
3088 'outer_loop: for input in &tx.input {
3089 let mut payment_data = None;
3090 let witness_items = input.witness.len();
3091 let htlctype = input.witness.last().map(|w| w.len()).and_then(HTLCType::scriptlen_to_htlctype);
3092 let prev_last_witness_len = input.witness.second_to_last().map(|w| w.len()).unwrap_or(0);
3093 let revocation_sig_claim = (witness_items == 3 && htlctype == Some(HTLCType::OfferedHTLC) && prev_last_witness_len == 33)
3094 || (witness_items == 3 && htlctype == Some(HTLCType::AcceptedHTLC) && prev_last_witness_len == 33);
3095 let accepted_preimage_claim = witness_items == 5 && htlctype == Some(HTLCType::AcceptedHTLC)
3096 && input.witness.second_to_last().unwrap().len() == 32;
3097 #[cfg(not(fuzzing))]
3098 let accepted_timeout_claim = witness_items == 3 && htlctype == Some(HTLCType::AcceptedHTLC) && !revocation_sig_claim;
3099 let offered_preimage_claim = witness_items == 3 && htlctype == Some(HTLCType::OfferedHTLC) &&
3100 !revocation_sig_claim && input.witness.second_to_last().unwrap().len() == 32;
3102 #[cfg(not(fuzzing))]
3103 let offered_timeout_claim = witness_items == 5 && htlctype == Some(HTLCType::OfferedHTLC);
3105 let mut payment_preimage = PaymentPreimage([0; 32]);
3106 if accepted_preimage_claim {
3107 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3108 } else if offered_preimage_claim {
3109 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3112 macro_rules! log_claim {
3113 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
3114 let outbound_htlc = $holder_tx == $htlc.offered;
3115 // HTLCs must either be claimed by a matching script type or through the
3117 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3118 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
3119 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3120 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
3121 // Further, only exactly one of the possible spend paths should have been
3122 // matched by any HTLC spend:
3123 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3124 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
3125 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
3126 revocation_sig_claim as u8, 1);
3127 if ($holder_tx && revocation_sig_claim) ||
3128 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
3129 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
3130 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3131 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3132 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" });
3134 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
3135 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3136 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3137 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
3142 macro_rules! check_htlc_valid_counterparty {
3143 ($counterparty_txid: expr, $htlc_output: expr) => {
3144 if let Some(txid) = $counterparty_txid {
3145 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
3146 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
3147 if let &Some(ref source) = pending_source {
3148 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
3149 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
3158 macro_rules! scan_commitment {
3159 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
3160 for (ref htlc_output, source_option) in $htlcs {
3161 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
3162 if let Some(ref source) = source_option {
3163 log_claim!($tx_info, $holder_tx, htlc_output, true);
3164 // We have a resolution of an HTLC either from one of our latest
3165 // holder commitment transactions or an unrevoked counterparty commitment
3166 // transaction. This implies we either learned a preimage, the HTLC
3167 // has timed out, or we screwed up. In any case, we should now
3168 // resolve the source HTLC with the original sender.
3169 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
3170 } else if !$holder_tx {
3171 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
3172 if payment_data.is_none() {
3173 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
3176 if payment_data.is_none() {
3177 log_claim!($tx_info, $holder_tx, htlc_output, false);
3178 let outbound_htlc = $holder_tx == htlc_output.offered;
3179 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3180 txid: tx.txid(), height, transaction: Some(tx.clone()),
3181 event: OnchainEvent::HTLCSpendConfirmation {
3182 commitment_tx_output_idx: input.previous_output.vout,
3183 preimage: if accepted_preimage_claim || offered_preimage_claim {
3184 Some(payment_preimage) } else { None },
3185 // If this is a payment to us (ie !outbound_htlc), wait for
3186 // the CSV delay before dropping the HTLC from claimable
3187 // balance if the claim was an HTLC-Success transaction (ie
3188 // accepted_preimage_claim).
3189 on_to_local_output_csv: if accepted_preimage_claim && !outbound_htlc {
3190 Some(self.on_holder_tx_csv) } else { None },
3193 continue 'outer_loop;
3200 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
3201 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3202 "our latest holder commitment tx", true);
3204 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
3205 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
3206 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3207 "our previous holder commitment tx", true);
3210 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
3211 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
3212 "counterparty commitment tx", false);
3215 // Check that scan_commitment, above, decided there is some source worth relaying an
3216 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
3217 if let Some((source, payment_hash, amount_msat)) = payment_data {
3218 if accepted_preimage_claim {
3219 if !self.pending_monitor_events.iter().any(
3220 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
3221 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3224 transaction: Some(tx.clone()),
3225 event: OnchainEvent::HTLCSpendConfirmation {
3226 commitment_tx_output_idx: input.previous_output.vout,
3227 preimage: Some(payment_preimage),
3228 on_to_local_output_csv: None,
3231 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3233 payment_preimage: Some(payment_preimage),
3235 htlc_value_satoshis: Some(amount_msat / 1000),
3238 } else if offered_preimage_claim {
3239 if !self.pending_monitor_events.iter().any(
3240 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
3241 upd.source == source
3243 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3245 transaction: Some(tx.clone()),
3247 event: OnchainEvent::HTLCSpendConfirmation {
3248 commitment_tx_output_idx: input.previous_output.vout,
3249 preimage: Some(payment_preimage),
3250 on_to_local_output_csv: None,
3253 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3255 payment_preimage: Some(payment_preimage),
3257 htlc_value_satoshis: Some(amount_msat / 1000),
3261 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
3262 if entry.height != height { return true; }
3264 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
3265 *htlc_source != source
3270 let entry = OnchainEventEntry {
3272 transaction: Some(tx.clone()),
3274 event: OnchainEvent::HTLCUpdate {
3275 source, payment_hash,
3276 htlc_value_satoshis: Some(amount_msat / 1000),
3277 commitment_tx_output_idx: Some(input.previous_output.vout),
3280 log_info!(logger, "Failing HTLC with payment_hash {} timeout by a spend tx, waiting for confirmation (at height {})", log_bytes!(payment_hash.0), entry.confirmation_threshold());
3281 self.onchain_events_awaiting_threshold_conf.push(entry);
3287 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
3288 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
3289 let mut spendable_output = None;
3290 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
3291 if i > ::core::u16::MAX as usize {
3292 // While it is possible that an output exists on chain which is greater than the
3293 // 2^16th output in a given transaction, this is only possible if the output is not
3294 // in a lightning transaction and was instead placed there by some third party who
3295 // wishes to give us money for no reason.
3296 // Namely, any lightning transactions which we pre-sign will never have anywhere
3297 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
3298 // scripts are not longer than one byte in length and because they are inherently
3299 // non-standard due to their size.
3300 // Thus, it is completely safe to ignore such outputs, and while it may result in
3301 // us ignoring non-lightning fund to us, that is only possible if someone fills
3302 // nearly a full block with garbage just to hit this case.
3305 if outp.script_pubkey == self.destination_script {
3306 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3307 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3308 output: outp.clone(),
3312 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
3313 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
3314 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
3315 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3316 per_commitment_point: broadcasted_holder_revokable_script.1,
3317 to_self_delay: self.on_holder_tx_csv,
3318 output: outp.clone(),
3319 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
3320 channel_keys_id: self.channel_keys_id,
3321 channel_value_satoshis: self.channel_value_satoshis,
3326 if self.counterparty_payment_script == outp.script_pubkey {
3327 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
3328 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3329 output: outp.clone(),
3330 channel_keys_id: self.channel_keys_id,
3331 channel_value_satoshis: self.channel_value_satoshis,
3335 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
3336 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3337 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3338 output: outp.clone(),
3343 if let Some(spendable_output) = spendable_output {
3344 let entry = OnchainEventEntry {
3346 transaction: Some(tx.clone()),
3348 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
3350 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
3351 self.onchain_events_awaiting_threshold_conf.push(entry);
3356 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
3358 T::Target: BroadcasterInterface,
3359 F::Target: FeeEstimator,
3362 fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3363 self.0.block_connected(header, txdata, height, &*self.1, &*self.2, &*self.3);
3366 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
3367 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
3371 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
3373 T::Target: BroadcasterInterface,
3374 F::Target: FeeEstimator,
3377 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3378 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
3381 fn transaction_unconfirmed(&self, txid: &Txid) {
3382 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
3385 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
3386 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
3389 fn get_relevant_txids(&self) -> Vec<Txid> {
3390 self.0.get_relevant_txids()
3394 const MAX_ALLOC_SIZE: usize = 64*1024;
3396 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
3397 for (BlockHash, ChannelMonitor<Signer>) {
3398 fn read<R: io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
3399 macro_rules! unwrap_obj {
3403 Err(_) => return Err(DecodeError::InvalidValue),
3408 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
3410 let latest_update_id: u64 = Readable::read(reader)?;
3411 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
3413 let destination_script = Readable::read(reader)?;
3414 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
3416 let revokable_address = Readable::read(reader)?;
3417 let per_commitment_point = Readable::read(reader)?;
3418 let revokable_script = Readable::read(reader)?;
3419 Some((revokable_address, per_commitment_point, revokable_script))
3422 _ => return Err(DecodeError::InvalidValue),
3424 let counterparty_payment_script = Readable::read(reader)?;
3425 let shutdown_script = {
3426 let script = <Script as Readable>::read(reader)?;
3427 if script.is_empty() { None } else { Some(script) }
3430 let channel_keys_id = Readable::read(reader)?;
3431 let holder_revocation_basepoint = Readable::read(reader)?;
3432 // Technically this can fail and serialize fail a round-trip, but only for serialization of
3433 // barely-init'd ChannelMonitors that we can't do anything with.
3434 let outpoint = OutPoint {
3435 txid: Readable::read(reader)?,
3436 index: Readable::read(reader)?,
3438 let funding_info = (outpoint, Readable::read(reader)?);
3439 let current_counterparty_commitment_txid = Readable::read(reader)?;
3440 let prev_counterparty_commitment_txid = Readable::read(reader)?;
3442 let counterparty_commitment_params = Readable::read(reader)?;
3443 let funding_redeemscript = Readable::read(reader)?;
3444 let channel_value_satoshis = Readable::read(reader)?;
3446 let their_cur_per_commitment_points = {
3447 let first_idx = <U48 as Readable>::read(reader)?.0;
3451 let first_point = Readable::read(reader)?;
3452 let second_point_slice: [u8; 33] = Readable::read(reader)?;
3453 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
3454 Some((first_idx, first_point, None))
3456 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
3461 let on_holder_tx_csv: u16 = Readable::read(reader)?;
3463 let commitment_secrets = Readable::read(reader)?;
3465 macro_rules! read_htlc_in_commitment {
3468 let offered: bool = Readable::read(reader)?;
3469 let amount_msat: u64 = Readable::read(reader)?;
3470 let cltv_expiry: u32 = Readable::read(reader)?;
3471 let payment_hash: PaymentHash = Readable::read(reader)?;
3472 let transaction_output_index: Option<u32> = Readable::read(reader)?;
3474 HTLCOutputInCommitment {
3475 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
3481 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
3482 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
3483 for _ in 0..counterparty_claimable_outpoints_len {
3484 let txid: Txid = Readable::read(reader)?;
3485 let htlcs_count: u64 = Readable::read(reader)?;
3486 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
3487 for _ in 0..htlcs_count {
3488 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
3490 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
3491 return Err(DecodeError::InvalidValue);
3495 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
3496 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
3497 for _ in 0..counterparty_commitment_txn_on_chain_len {
3498 let txid: Txid = Readable::read(reader)?;
3499 let commitment_number = <U48 as Readable>::read(reader)?.0;
3500 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
3501 return Err(DecodeError::InvalidValue);
3505 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3506 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3507 for _ in 0..counterparty_hash_commitment_number_len {
3508 let payment_hash: PaymentHash = Readable::read(reader)?;
3509 let commitment_number = <U48 as Readable>::read(reader)?.0;
3510 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3511 return Err(DecodeError::InvalidValue);
3515 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3516 match <u8 as Readable>::read(reader)? {
3519 Some(Readable::read(reader)?)
3521 _ => return Err(DecodeError::InvalidValue),
3523 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3525 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3526 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3528 let payment_preimages_len: u64 = Readable::read(reader)?;
3529 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3530 for _ in 0..payment_preimages_len {
3531 let preimage: PaymentPreimage = Readable::read(reader)?;
3532 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3533 if let Some(_) = payment_preimages.insert(hash, preimage) {
3534 return Err(DecodeError::InvalidValue);
3538 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3539 let mut pending_monitor_events = Some(
3540 Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
3541 for _ in 0..pending_monitor_events_len {
3542 let ev = match <u8 as Readable>::read(reader)? {
3543 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3544 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0),
3545 _ => return Err(DecodeError::InvalidValue)
3547 pending_monitor_events.as_mut().unwrap().push(ev);
3550 let pending_events_len: u64 = Readable::read(reader)?;
3551 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3552 for _ in 0..pending_events_len {
3553 if let Some(event) = MaybeReadable::read(reader)? {
3554 pending_events.push(event);
3558 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
3560 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
3561 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
3562 for _ in 0..waiting_threshold_conf_len {
3563 if let Some(val) = MaybeReadable::read(reader)? {
3564 onchain_events_awaiting_threshold_conf.push(val);
3568 let outputs_to_watch_len: u64 = Readable::read(reader)?;
3569 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>>())));
3570 for _ in 0..outputs_to_watch_len {
3571 let txid = Readable::read(reader)?;
3572 let outputs_len: u64 = Readable::read(reader)?;
3573 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
3574 for _ in 0..outputs_len {
3575 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
3577 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
3578 return Err(DecodeError::InvalidValue);
3581 let onchain_tx_handler: OnchainTxHandler<Signer> = ReadableArgs::read(reader, keys_manager)?;
3583 let lockdown_from_offchain = Readable::read(reader)?;
3584 let holder_tx_signed = Readable::read(reader)?;
3586 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
3587 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
3588 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
3589 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
3590 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
3591 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
3592 return Err(DecodeError::InvalidValue);
3596 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
3597 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
3598 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
3599 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
3600 return Err(DecodeError::InvalidValue);
3603 let mut funding_spend_confirmed = None;
3604 let mut htlcs_resolved_on_chain = Some(Vec::new());
3605 let mut funding_spend_seen = Some(false);
3606 let mut counterparty_node_id = None;
3607 let mut confirmed_commitment_tx_counterparty_output = None;
3608 read_tlv_fields!(reader, {
3609 (1, funding_spend_confirmed, option),
3610 (3, htlcs_resolved_on_chain, vec_type),
3611 (5, pending_monitor_events, vec_type),
3612 (7, funding_spend_seen, option),
3613 (9, counterparty_node_id, option),
3614 (11, confirmed_commitment_tx_counterparty_output, option),
3617 let mut secp_ctx = Secp256k1::new();
3618 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
3620 Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
3622 commitment_transaction_number_obscure_factor,
3625 broadcasted_holder_revokable_script,
3626 counterparty_payment_script,
3630 holder_revocation_basepoint,
3632 current_counterparty_commitment_txid,
3633 prev_counterparty_commitment_txid,
3635 counterparty_commitment_params,
3636 funding_redeemscript,
3637 channel_value_satoshis,
3638 their_cur_per_commitment_points,
3643 counterparty_claimable_outpoints,
3644 counterparty_commitment_txn_on_chain,
3645 counterparty_hash_commitment_number,
3647 prev_holder_signed_commitment_tx,
3648 current_holder_commitment_tx,
3649 current_counterparty_commitment_number,
3650 current_holder_commitment_number,
3653 pending_monitor_events: pending_monitor_events.unwrap(),
3656 onchain_events_awaiting_threshold_conf,
3661 lockdown_from_offchain,
3663 funding_spend_seen: funding_spend_seen.unwrap(),
3664 funding_spend_confirmed,
3665 confirmed_commitment_tx_counterparty_output,
3666 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
3669 counterparty_node_id,
3678 use bitcoin::blockdata::block::BlockHeader;
3679 use bitcoin::blockdata::script::{Script, Builder};
3680 use bitcoin::blockdata::opcodes;
3681 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
3682 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
3683 use bitcoin::util::sighash;
3684 use bitcoin::hashes::Hash;
3685 use bitcoin::hashes::sha256::Hash as Sha256;
3686 use bitcoin::hashes::hex::FromHex;
3687 use bitcoin::hash_types::{BlockHash, Txid};
3688 use bitcoin::network::constants::Network;
3689 use bitcoin::secp256k1::{SecretKey,PublicKey};
3690 use bitcoin::secp256k1::Secp256k1;
3694 use crate::chain::chaininterface::LowerBoundedFeeEstimator;
3696 use super::ChannelMonitorUpdateStep;
3697 use ::{check_added_monitors, check_closed_broadcast, check_closed_event, check_spends, get_local_commitment_txn, get_monitor, get_route_and_payment_hash, unwrap_send_err};
3698 use chain::{BestBlock, Confirm};
3699 use chain::channelmonitor::ChannelMonitor;
3700 use chain::package::{weight_offered_htlc, weight_received_htlc, weight_revoked_offered_htlc, weight_revoked_received_htlc, WEIGHT_REVOKED_OUTPUT};
3701 use chain::transaction::OutPoint;
3702 use chain::keysinterface::InMemorySigner;
3703 use ln::{PaymentPreimage, PaymentHash};
3705 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
3706 use ln::channelmanager::PaymentSendFailure;
3707 use ln::features::InitFeatures;
3708 use ln::functional_test_utils::*;
3709 use ln::script::ShutdownScript;
3710 use util::errors::APIError;
3711 use util::events::{ClosureReason, MessageSendEventsProvider};
3712 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
3713 use util::ser::{ReadableArgs, Writeable};
3714 use sync::{Arc, Mutex};
3716 use bitcoin::{PackedLockTime, Sequence, TxMerkleNode, Witness};
3719 fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
3720 // Previously, monitor updates were allowed freely even after a funding-spend transaction
3721 // confirmed. This would allow a race condition where we could receive a payment (including
3722 // the counterparty revoking their broadcasted state!) and accept it without recourse as
3723 // long as the ChannelMonitor receives the block first, the full commitment update dance
3724 // occurs after the block is connected, and before the ChannelManager receives the block.
3725 // Obviously this is an incredibly contrived race given the counterparty would be risking
3726 // their full channel balance for it, but its worth fixing nonetheless as it makes the
3727 // potential ChannelMonitor states simpler to reason about.
3729 // This test checks said behavior, as well as ensuring a ChannelMonitorUpdate with multiple
3730 // updates is handled correctly in such conditions.
3731 let chanmon_cfgs = create_chanmon_cfgs(3);
3732 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
3733 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
3734 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
3735 let channel = create_announced_chan_between_nodes(
3736 &nodes, 0, 1, InitFeatures::known(), InitFeatures::known());
3737 create_announced_chan_between_nodes(
3738 &nodes, 1, 2, InitFeatures::known(), InitFeatures::known());
3740 // Rebalance somewhat
3741 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
3743 // First route two payments for testing at the end
3744 let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
3745 let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
3747 let local_txn = get_local_commitment_txn!(nodes[1], channel.2);
3748 assert_eq!(local_txn.len(), 1);
3749 let remote_txn = get_local_commitment_txn!(nodes[0], channel.2);
3750 assert_eq!(remote_txn.len(), 3); // Commitment and two HTLC-Timeouts
3751 check_spends!(remote_txn[1], remote_txn[0]);
3752 check_spends!(remote_txn[2], remote_txn[0]);
3753 let broadcast_tx = if use_local_txn { &local_txn[0] } else { &remote_txn[0] };
3755 // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
3756 // channel is now closed, but the ChannelManager doesn't know that yet.
3757 let new_header = BlockHeader {
3758 version: 2, time: 0, bits: 0, nonce: 0,
3759 prev_blockhash: nodes[0].best_block_info().0,
3760 merkle_root: TxMerkleNode::all_zeros() };
3761 let conf_height = nodes[0].best_block_info().1 + 1;
3762 nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
3763 &[(0, broadcast_tx)], conf_height);
3765 let (_, pre_update_monitor) = <(BlockHash, ChannelMonitor<InMemorySigner>)>::read(
3766 &mut io::Cursor::new(&get_monitor!(nodes[1], channel.2).encode()),
3767 &nodes[1].keys_manager.backing).unwrap();
3769 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
3770 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
3771 let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[1], nodes[0], 100_000);
3772 unwrap_send_err!(nodes[1].node.send_payment(&route, payment_hash, &Some(payment_secret)),
3773 true, APIError::ChannelUnavailable { ref err },
3774 assert!(err.contains("ChannelMonitor storage failure")));
3775 check_added_monitors!(nodes[1], 2); // After the failure we generate a close-channel monitor update
3776 check_closed_broadcast!(nodes[1], true);
3777 check_closed_event!(nodes[1], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() });
3779 // Build a new ChannelMonitorUpdate which contains both the failing commitment tx update
3780 // and provides the claim preimages for the two pending HTLCs. The first update generates
3781 // an error, but the point of this test is to ensure the later updates are still applied.
3782 let monitor_updates = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
3783 let mut replay_update = monitor_updates.get(&channel.2).unwrap().iter().rev().skip(1).next().unwrap().clone();
3784 assert_eq!(replay_update.updates.len(), 1);
3785 if let ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } = replay_update.updates[0] {
3786 } else { panic!(); }
3787 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_1 });
3788 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_2 });
3790 let broadcaster = TestBroadcaster::new(Arc::clone(&nodes[1].blocks));
3792 pre_update_monitor.update_monitor(&replay_update, &&broadcaster, &chanmon_cfgs[1].fee_estimator, &nodes[1].logger)
3794 // Even though we error'd on the first update, we should still have generated an HTLC claim
3796 let txn_broadcasted = broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
3797 assert!(txn_broadcasted.len() >= 2);
3798 let htlc_txn = txn_broadcasted.iter().filter(|tx| {
3799 assert_eq!(tx.input.len(), 1);
3800 tx.input[0].previous_output.txid == broadcast_tx.txid()
3801 }).collect::<Vec<_>>();
3802 assert_eq!(htlc_txn.len(), 2);
3803 check_spends!(htlc_txn[0], broadcast_tx);
3804 check_spends!(htlc_txn[1], broadcast_tx);
3807 fn test_funding_spend_refuses_updates() {
3808 do_test_funding_spend_refuses_updates(true);
3809 do_test_funding_spend_refuses_updates(false);
3813 fn test_prune_preimages() {
3814 let secp_ctx = Secp256k1::new();
3815 let logger = Arc::new(TestLogger::new());
3816 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
3817 let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
3819 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3820 let dummy_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
3822 let mut preimages = Vec::new();
3825 let preimage = PaymentPreimage([i; 32]);
3826 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3827 preimages.push((preimage, hash));
3831 macro_rules! preimages_slice_to_htlc_outputs {
3832 ($preimages_slice: expr) => {
3834 let mut res = Vec::new();
3835 for (idx, preimage) in $preimages_slice.iter().enumerate() {
3836 res.push((HTLCOutputInCommitment {
3840 payment_hash: preimage.1.clone(),
3841 transaction_output_index: Some(idx as u32),
3848 macro_rules! preimages_to_holder_htlcs {
3849 ($preimages_slice: expr) => {
3851 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
3852 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
3858 macro_rules! test_preimages_exist {
3859 ($preimages_slice: expr, $monitor: expr) => {
3860 for preimage in $preimages_slice {
3861 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
3866 let keys = InMemorySigner::new(
3868 SecretKey::from_slice(&[41; 32]).unwrap(),
3869 SecretKey::from_slice(&[41; 32]).unwrap(),
3870 SecretKey::from_slice(&[41; 32]).unwrap(),
3871 SecretKey::from_slice(&[41; 32]).unwrap(),
3872 SecretKey::from_slice(&[41; 32]).unwrap(),
3873 SecretKey::from_slice(&[41; 32]).unwrap(),
3879 let counterparty_pubkeys = ChannelPublicKeys {
3880 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
3881 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
3882 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
3883 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
3884 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
3886 let funding_outpoint = OutPoint { txid: Txid::all_zeros(), index: u16::max_value() };
3887 let channel_parameters = ChannelTransactionParameters {
3888 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
3889 holder_selected_contest_delay: 66,
3890 is_outbound_from_holder: true,
3891 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
3892 pubkeys: counterparty_pubkeys,
3893 selected_contest_delay: 67,
3895 funding_outpoint: Some(funding_outpoint),
3898 // Prune with one old state and a holder commitment tx holding a few overlaps with the
3900 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3901 let best_block = BestBlock::from_genesis(Network::Testnet);
3902 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
3903 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
3904 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
3905 &channel_parameters,
3906 Script::new(), 46, 0,
3907 HolderCommitmentTransaction::dummy(), best_block, dummy_key);
3909 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
3910 let dummy_txid = dummy_tx.txid();
3911 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
3912 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
3913 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
3914 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
3915 for &(ref preimage, ref hash) in preimages.iter() {
3916 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
3917 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
3920 // Now provide a secret, pruning preimages 10-15
3921 let mut secret = [0; 32];
3922 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
3923 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
3924 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
3925 test_preimages_exist!(&preimages[0..10], monitor);
3926 test_preimages_exist!(&preimages[15..20], monitor);
3928 // Now provide a further secret, pruning preimages 15-17
3929 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
3930 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
3931 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
3932 test_preimages_exist!(&preimages[0..10], monitor);
3933 test_preimages_exist!(&preimages[17..20], monitor);
3935 // Now update holder commitment tx info, pruning only element 18 as we still care about the
3936 // previous commitment tx's preimages too
3937 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
3938 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
3939 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
3940 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
3941 test_preimages_exist!(&preimages[0..10], monitor);
3942 test_preimages_exist!(&preimages[18..20], monitor);
3944 // But if we do it again, we'll prune 5-10
3945 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
3946 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
3947 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
3948 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
3949 test_preimages_exist!(&preimages[0..5], monitor);
3953 fn test_claim_txn_weight_computation() {
3954 // We test Claim txn weight, knowing that we want expected weigth and
3955 // not actual case to avoid sigs and time-lock delays hell variances.
3957 let secp_ctx = Secp256k1::new();
3958 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
3959 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
3961 macro_rules! sign_input {
3962 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr, $opt_anchors: expr) => {
3963 let htlc = HTLCOutputInCommitment {
3964 offered: if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_offered_htlc($opt_anchors) { true } else { false },
3966 cltv_expiry: 2 << 16,
3967 payment_hash: PaymentHash([1; 32]),
3968 transaction_output_index: Some($idx as u32),
3970 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, $opt_anchors, &pubkey, &pubkey, &pubkey) };
3971 let sighash = hash_to_message!(&$sighash_parts.segwit_signature_hash($idx, &redeem_script, $amount, EcdsaSighashType::All).unwrap()[..]);
3972 let sig = secp_ctx.sign_ecdsa(&sighash, &privkey);
3973 let mut ser_sig = sig.serialize_der().to_vec();
3974 ser_sig.push(EcdsaSighashType::All as u8);
3975 $sum_actual_sigs += ser_sig.len();
3976 let witness = $sighash_parts.witness_mut($idx).unwrap();
3977 witness.push(ser_sig);
3978 if *$weight == WEIGHT_REVOKED_OUTPUT {
3979 witness.push(vec!(1));
3980 } else if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_revoked_received_htlc($opt_anchors) {
3981 witness.push(pubkey.clone().serialize().to_vec());
3982 } else if *$weight == weight_received_htlc($opt_anchors) {
3983 witness.push(vec![0]);
3985 witness.push(PaymentPreimage([1; 32]).0.to_vec());
3987 witness.push(redeem_script.into_bytes());
3988 let witness = witness.to_vec();
3989 println!("witness[0] {}", witness[0].len());
3990 println!("witness[1] {}", witness[1].len());
3991 println!("witness[2] {}", witness[2].len());
3995 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3996 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3998 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3999 for &opt_anchors in [false, true].iter() {
4000 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4001 let mut sum_actual_sigs = 0;
4003 claim_tx.input.push(TxIn {
4004 previous_output: BitcoinOutPoint {
4008 script_sig: Script::new(),
4009 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4010 witness: Witness::new(),
4013 claim_tx.output.push(TxOut {
4014 script_pubkey: script_pubkey.clone(),
4017 let base_weight = claim_tx.weight();
4018 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, weight_revoked_offered_htlc(opt_anchors), weight_revoked_offered_htlc(opt_anchors), weight_revoked_received_htlc(opt_anchors)];
4019 let mut inputs_total_weight = 2; // count segwit flags
4021 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4022 for (idx, inp) in inputs_weight.iter().enumerate() {
4023 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4024 inputs_total_weight += inp;
4027 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4030 // Claim tx with 1 offered HTLCs, 3 received HTLCs
4031 for &opt_anchors in [false, true].iter() {
4032 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4033 let mut sum_actual_sigs = 0;
4035 claim_tx.input.push(TxIn {
4036 previous_output: BitcoinOutPoint {
4040 script_sig: Script::new(),
4041 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4042 witness: Witness::new(),
4045 claim_tx.output.push(TxOut {
4046 script_pubkey: script_pubkey.clone(),
4049 let base_weight = claim_tx.weight();
4050 let inputs_weight = vec![weight_offered_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors), weight_received_htlc(opt_anchors)];
4051 let mut inputs_total_weight = 2; // count segwit flags
4053 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4054 for (idx, inp) in inputs_weight.iter().enumerate() {
4055 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4056 inputs_total_weight += inp;
4059 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4062 // Justice tx with 1 revoked HTLC-Success tx output
4063 for &opt_anchors in [false, true].iter() {
4064 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4065 let mut sum_actual_sigs = 0;
4066 claim_tx.input.push(TxIn {
4067 previous_output: BitcoinOutPoint {
4071 script_sig: Script::new(),
4072 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4073 witness: Witness::new(),
4075 claim_tx.output.push(TxOut {
4076 script_pubkey: script_pubkey.clone(),
4079 let base_weight = claim_tx.weight();
4080 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
4081 let mut inputs_total_weight = 2; // count segwit flags
4083 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4084 for (idx, inp) in inputs_weight.iter().enumerate() {
4085 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, opt_anchors);
4086 inputs_total_weight += inp;
4089 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
4093 // Further testing is done in the ChannelManager integration tests.