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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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::{Block, BlockHeader};
24 use bitcoin::blockdata::transaction::{TxOut,Transaction};
25 use bitcoin::blockdata::script::{Script, Builder};
26 use bitcoin::blockdata::opcodes;
28 use bitcoin::hashes::Hash;
29 use bitcoin::hashes::sha256::Hash as Sha256;
30 use bitcoin::hash_types::{Txid, BlockHash, WPubkeyHash};
32 use bitcoin::secp256k1::{Secp256k1,Signature};
33 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
34 use bitcoin::secp256k1;
36 use ln::{PaymentHash, PaymentPreimage};
37 use ln::msgs::DecodeError;
39 use ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCType, ChannelTransactionParameters, HolderCommitmentTransaction};
40 use ln::channelmanager::HTLCSource;
42 use chain::{BestBlock, WatchedOutput};
43 use chain::chaininterface::{BroadcasterInterface, FeeEstimator};
44 use chain::transaction::{OutPoint, TransactionData};
45 use chain::keysinterface::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, Sign, KeysInterface};
46 use chain::onchaintx::OnchainTxHandler;
47 use chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
49 use util::logger::Logger;
50 use util::ser::{Readable, ReadableArgs, MaybeReadable, Writer, Writeable, U48, OptionDeserWrapper};
52 use util::events::Event;
56 use io::{self, Error};
60 /// An update generated by the underlying Channel itself which contains some new information the
61 /// ChannelMonitor should be made aware of.
62 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
65 pub struct ChannelMonitorUpdate {
66 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
67 /// The sequence number of this update. Updates *must* be replayed in-order according to this
68 /// sequence number (and updates may panic if they are not). The update_id values are strictly
69 /// increasing and increase by one for each new update, with one exception specified below.
71 /// This sequence number is also used to track up to which points updates which returned
72 /// ChannelMonitorUpdateErr::TemporaryFailure have been applied to all copies of a given
73 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
75 /// The only instance where update_id values are not strictly increasing is the case where we
76 /// allow post-force-close updates with a special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. See
77 /// its docs for more details.
82 /// (1) a channel has been force closed and
83 /// (2) we receive a preimage from a forward link that allows us to spend an HTLC output on
84 /// this channel's (the backward link's) broadcasted commitment transaction
85 /// then we allow the `ChannelManager` to send a `ChannelMonitorUpdate` with this update ID,
86 /// with the update providing said payment preimage. No other update types are allowed after
88 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
90 impl Writeable for ChannelMonitorUpdate {
91 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
92 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
93 self.update_id.write(w)?;
94 (self.updates.len() as u64).write(w)?;
95 for update_step in self.updates.iter() {
96 update_step.write(w)?;
98 write_tlv_fields!(w, {});
102 impl Readable for ChannelMonitorUpdate {
103 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
104 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
105 let update_id: u64 = Readable::read(r)?;
106 let len: u64 = Readable::read(r)?;
107 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
109 if let Some(upd) = MaybeReadable::read(r)? {
113 read_tlv_fields!(r, {});
114 Ok(Self { update_id, updates })
118 /// An error enum representing a failure to persist a channel monitor update.
119 #[derive(Clone, Copy, Debug, PartialEq)]
120 pub enum ChannelMonitorUpdateErr {
121 /// Used to indicate a temporary failure (eg connection to a watchtower or remote backup of
122 /// our state failed, but is expected to succeed at some point in the future).
124 /// Such a failure will "freeze" a channel, preventing us from revoking old states or
125 /// submitting new commitment transactions to the counterparty. Once the update(s) which failed
126 /// have been successfully applied, ChannelManager::channel_monitor_updated can be used to
127 /// restore the channel to an operational state.
129 /// Note that a given ChannelManager will *never* re-generate a given ChannelMonitorUpdate. If
130 /// you return a TemporaryFailure you must ensure that it is written to disk safely before
131 /// writing out the latest ChannelManager state.
133 /// Even when a channel has been "frozen" updates to the ChannelMonitor can continue to occur
134 /// (eg if an inbound HTLC which we forwarded was claimed upstream resulting in us attempting
135 /// to claim it on this channel) and those updates must be applied wherever they can be. At
136 /// least one such updated ChannelMonitor must be persisted otherwise PermanentFailure should
137 /// be returned to get things on-chain ASAP using only the in-memory copy. Obviously updates to
138 /// the channel which would invalidate previous ChannelMonitors are not made when a channel has
141 /// Note that even if updates made after TemporaryFailure succeed you must still call
142 /// channel_monitor_updated to ensure you have the latest monitor and re-enable normal channel
145 /// Note that the update being processed here will not be replayed for you when you call
146 /// ChannelManager::channel_monitor_updated, so you must store the update itself along
147 /// with the persisted ChannelMonitor on your own local disk prior to returning a
148 /// TemporaryFailure. You may, of course, employ a journaling approach, storing only the
149 /// ChannelMonitorUpdate on disk without updating the monitor itself, replaying the journal at
152 /// For deployments where a copy of ChannelMonitors and other local state are backed up in a
153 /// remote location (with local copies persisted immediately), it is anticipated that all
154 /// updates will return TemporaryFailure until the remote copies could be updated.
156 /// Used to indicate no further channel monitor updates will be allowed (eg we've moved on to a
157 /// different watchtower and cannot update with all watchtowers that were previously informed
158 /// of this channel).
160 /// At reception of this error, ChannelManager will force-close the channel and return at
161 /// least a final ChannelMonitorUpdate::ChannelForceClosed which must be delivered to at
162 /// least one ChannelMonitor copy. Revocation secret MUST NOT be released and offchain channel
163 /// update must be rejected.
165 /// This failure may also signal a failure to update the local persisted copy of one of
166 /// the channel monitor instance.
168 /// Note that even when you fail a holder commitment transaction update, you must store the
169 /// update to ensure you can claim from it in case of a duplicate copy of this ChannelMonitor
170 /// broadcasts it (e.g distributed channel-monitor deployment)
172 /// In case of distributed watchtowers deployment, the new version must be written to disk, as
173 /// state may have been stored but rejected due to a block forcing a commitment broadcast. This
174 /// storage is used to claim outputs of rejected state confirmed onchain by another watchtower,
175 /// lagging behind on block processing.
179 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
180 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
181 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
183 /// Contains a developer-readable error message.
184 #[derive(Clone, Debug)]
185 pub struct MonitorUpdateError(pub &'static str);
187 /// An event to be processed by the ChannelManager.
188 #[derive(Clone, PartialEq)]
189 pub enum MonitorEvent {
190 /// A monitor event containing an HTLCUpdate.
191 HTLCEvent(HTLCUpdate),
193 /// A monitor event that the Channel's commitment transaction was broadcasted.
194 CommitmentTxBroadcasted(OutPoint),
197 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
198 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
199 /// preimage claim backward will lead to loss of funds.
200 #[derive(Clone, PartialEq)]
201 pub struct HTLCUpdate {
202 pub(crate) payment_hash: PaymentHash,
203 pub(crate) payment_preimage: Option<PaymentPreimage>,
204 pub(crate) source: HTLCSource,
205 pub(crate) onchain_value_satoshis: Option<u64>,
207 impl_writeable_tlv_based!(HTLCUpdate, {
208 (0, payment_hash, required),
209 (1, onchain_value_satoshis, option),
210 (2, source, required),
211 (4, payment_preimage, option),
214 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
215 /// instead claiming it in its own individual transaction.
216 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
217 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
218 /// HTLC-Success transaction.
219 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
220 /// transaction confirmed (and we use it in a few more, equivalent, places).
221 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
222 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
223 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
224 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
225 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
226 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
227 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
228 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
229 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
230 /// accurate block height.
231 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
232 /// with at worst this delay, so we are not only using this value as a mercy for them but also
233 /// us as a safeguard to delay with enough time.
234 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
235 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
236 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
239 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
240 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
241 /// by a [`ChannelMonitor`] may be incorrect.
242 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
243 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
244 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
245 // keep bumping another claim tx to solve the outpoint.
246 pub const ANTI_REORG_DELAY: u32 = 6;
247 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
248 /// refuse to accept a new HTLC.
250 /// This is used for a few separate purposes:
251 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
252 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
254 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
255 /// condition with the above), we will fail this HTLC without telling the user we received it,
256 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
257 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
259 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
260 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
262 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
263 /// in a race condition between the user connecting a block (which would fail it) and the user
264 /// providing us the preimage (which would claim it).
266 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
267 /// end up force-closing the channel on us to claim it.
268 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
270 // TODO(devrandom) replace this with HolderCommitmentTransaction
271 #[derive(Clone, PartialEq)]
272 struct HolderSignedTx {
273 /// txid of the transaction in tx, just used to make comparison faster
275 revocation_key: PublicKey,
276 a_htlc_key: PublicKey,
277 b_htlc_key: PublicKey,
278 delayed_payment_key: PublicKey,
279 per_commitment_point: PublicKey,
280 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
281 to_self_value_sat: u64,
284 impl_writeable_tlv_based!(HolderSignedTx, {
286 // Note that this is filled in with data from OnchainTxHandler if it's missing.
287 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
288 (1, to_self_value_sat, (default_value, u64::max_value())),
289 (2, revocation_key, required),
290 (4, a_htlc_key, required),
291 (6, b_htlc_key, required),
292 (8, delayed_payment_key, required),
293 (10, per_commitment_point, required),
294 (12, feerate_per_kw, required),
295 (14, htlc_outputs, vec_type)
298 /// We use this to track static counterparty commitment transaction data and to generate any
299 /// justice or 2nd-stage preimage/timeout transactions.
301 struct CounterpartyCommitmentParameters {
302 counterparty_delayed_payment_base_key: PublicKey,
303 counterparty_htlc_base_key: PublicKey,
304 on_counterparty_tx_csv: u16,
307 impl Writeable for CounterpartyCommitmentParameters {
308 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
309 w.write_all(&byte_utils::be64_to_array(0))?;
310 write_tlv_fields!(w, {
311 (0, self.counterparty_delayed_payment_base_key, required),
312 (2, self.counterparty_htlc_base_key, required),
313 (4, self.on_counterparty_tx_csv, required),
318 impl Readable for CounterpartyCommitmentParameters {
319 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
320 let counterparty_commitment_transaction = {
321 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
322 // used. Read it for compatibility.
323 let per_htlc_len: u64 = Readable::read(r)?;
324 for _ in 0..per_htlc_len {
325 let _txid: Txid = Readable::read(r)?;
326 let htlcs_count: u64 = Readable::read(r)?;
327 for _ in 0..htlcs_count {
328 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
332 let mut counterparty_delayed_payment_base_key = OptionDeserWrapper(None);
333 let mut counterparty_htlc_base_key = OptionDeserWrapper(None);
334 let mut on_counterparty_tx_csv: u16 = 0;
335 read_tlv_fields!(r, {
336 (0, counterparty_delayed_payment_base_key, required),
337 (2, counterparty_htlc_base_key, required),
338 (4, on_counterparty_tx_csv, required),
340 CounterpartyCommitmentParameters {
341 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
342 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
343 on_counterparty_tx_csv,
346 Ok(counterparty_commitment_transaction)
350 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
351 /// transaction causing it.
353 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
355 struct OnchainEventEntry {
361 impl OnchainEventEntry {
362 fn confirmation_threshold(&self) -> u32 {
363 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
365 OnchainEvent::MaturingOutput {
366 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
368 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
369 // it's broadcastable when we see the previous block.
370 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
372 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
373 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
374 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
375 // it's broadcastable when we see the previous block.
376 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
383 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
384 best_block.height() >= self.confirmation_threshold()
388 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
389 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
392 /// An outbound HTLC failing after a transaction is confirmed. Used
393 /// * when an outbound HTLC output is spent by us after the HTLC timed out
394 /// * an outbound HTLC which was not present in the commitment transaction which appeared
395 /// on-chain (either because it was not fully committed to or it was dust).
396 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
397 /// appearing only as an `HTLCSpendConfirmation`, below.
400 payment_hash: PaymentHash,
401 onchain_value_satoshis: Option<u64>,
402 /// None in the second case, above, ie when there is no relevant output in the commitment
403 /// transaction which appeared on chain.
404 input_idx: Option<u32>,
407 descriptor: SpendableOutputDescriptor,
409 /// A spend of the funding output, either a commitment transaction or a cooperative closing
411 FundingSpendConfirmation {
412 /// The CSV delay for the output of the funding spend transaction (implying it is a local
413 /// commitment transaction, and this is the delay on the to_self output).
414 on_local_output_csv: Option<u16>,
416 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
417 /// is constructed. This is used when
418 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
419 /// immediately claim the HTLC on the inbound edge and track the resolution here,
420 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
421 /// * an inbound HTLC is claimed by us (with a preimage).
422 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
424 HTLCSpendConfirmation {
426 /// If the claim was made by either party with a preimage, this is filled in
427 preimage: Option<PaymentPreimage>,
428 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
429 /// we set this to the output CSV value which we will have to wait until to spend the
430 /// output (and generate a SpendableOutput event).
431 on_to_local_output_csv: Option<u16>,
435 impl Writeable for OnchainEventEntry {
436 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
437 write_tlv_fields!(writer, {
438 (0, self.txid, required),
439 (2, self.height, required),
440 (4, self.event, required),
446 impl MaybeReadable for OnchainEventEntry {
447 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
448 let mut txid = Default::default();
450 let mut event = None;
451 read_tlv_fields!(reader, {
453 (2, height, required),
454 (4, event, ignorable),
456 if let Some(ev) = event {
457 Ok(Some(Self { txid, height, event: ev }))
464 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
466 (0, source, required),
467 (1, onchain_value_satoshis, option),
468 (2, payment_hash, required),
469 (3, input_idx, option),
471 (1, MaturingOutput) => {
472 (0, descriptor, required),
474 (3, FundingSpendConfirmation) => {
475 (0, on_local_output_csv, option),
477 (5, HTLCSpendConfirmation) => {
478 (0, input_idx, required),
479 (2, preimage, option),
480 (4, on_to_local_output_csv, option),
485 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
487 pub(crate) enum ChannelMonitorUpdateStep {
488 LatestHolderCommitmentTXInfo {
489 commitment_tx: HolderCommitmentTransaction,
490 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
492 LatestCounterpartyCommitmentTXInfo {
493 commitment_txid: Txid,
494 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
495 commitment_number: u64,
496 their_revocation_point: PublicKey,
499 payment_preimage: PaymentPreimage,
505 /// Used to indicate that the no future updates will occur, and likely that the latest holder
506 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
508 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
509 /// think we've fallen behind!
510 should_broadcast: bool,
513 scriptpubkey: Script,
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_revocation_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,
596 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
598 struct IrrevocablyResolvedHTLC {
600 /// Only set if the HTLC claim was ours using a payment preimage
601 payment_preimage: Option<PaymentPreimage>,
604 impl_writeable_tlv_based!(IrrevocablyResolvedHTLC, {
605 (0, input_idx, required),
606 (2, payment_preimage, option),
609 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
610 /// on-chain transactions to ensure no loss of funds occurs.
612 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
613 /// information and are actively monitoring the chain.
615 /// Pending Events or updated HTLCs which have not yet been read out by
616 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
617 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
618 /// gotten are fully handled before re-serializing the new state.
620 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
621 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
622 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
623 /// returned block hash and the the current chain and then reconnecting blocks to get to the
624 /// best chain) upon deserializing the object!
625 pub struct ChannelMonitor<Signer: Sign> {
627 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
629 inner: Mutex<ChannelMonitorImpl<Signer>>,
632 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
633 latest_update_id: u64,
634 commitment_transaction_number_obscure_factor: u64,
636 destination_script: Script,
637 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
638 counterparty_payment_script: Script,
639 shutdown_script: Option<Script>,
641 channel_keys_id: [u8; 32],
642 holder_revocation_basepoint: PublicKey,
643 funding_info: (OutPoint, Script),
644 current_counterparty_commitment_txid: Option<Txid>,
645 prev_counterparty_commitment_txid: Option<Txid>,
647 counterparty_commitment_params: CounterpartyCommitmentParameters,
648 funding_redeemscript: Script,
649 channel_value_satoshis: u64,
650 // first is the idx of the first of the two revocation points
651 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
653 on_holder_tx_csv: u16,
655 commitment_secrets: CounterpartyCommitmentSecrets,
656 /// The set of outpoints in each counterparty commitment transaction. We always need at least
657 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
658 /// transaction broadcast as we need to be able to construct the witness script in all cases.
659 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
660 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
661 /// Nor can we figure out their commitment numbers without the commitment transaction they are
662 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
663 /// commitment transactions which we find on-chain, mapping them to the commitment number which
664 /// can be used to derive the revocation key and claim the transactions.
665 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
666 /// Cache used to make pruning of payment_preimages faster.
667 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
668 /// counterparty transactions (ie should remain pretty small).
669 /// Serialized to disk but should generally not be sent to Watchtowers.
670 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
672 // We store two holder commitment transactions to avoid any race conditions where we may update
673 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
674 // various monitors for one channel being out of sync, and us broadcasting a holder
675 // transaction for which we have deleted claim information on some watchtowers.
676 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
677 current_holder_commitment_tx: HolderSignedTx,
679 // Used just for ChannelManager to make sure it has the latest channel data during
681 current_counterparty_commitment_number: u64,
682 // Used just for ChannelManager to make sure it has the latest channel data during
684 current_holder_commitment_number: u64,
686 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
688 pending_monitor_events: Vec<MonitorEvent>,
689 pending_events: Vec<Event>,
691 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
692 // which to take actions once they reach enough confirmations. Each entry includes the
693 // transaction's id and the height when the transaction was confirmed on chain.
694 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
696 // If we get serialized out and re-read, we need to make sure that the chain monitoring
697 // interface knows about the TXOs that we want to be notified of spends of. We could probably
698 // be smart and derive them from the above storage fields, but its much simpler and more
699 // Obviously Correct (tm) if we just keep track of them explicitly.
700 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
703 pub onchain_tx_handler: OnchainTxHandler<Signer>,
705 onchain_tx_handler: OnchainTxHandler<Signer>,
707 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
708 // channel has been force-closed. After this is set, no further holder commitment transaction
709 // updates may occur, and we panic!() if one is provided.
710 lockdown_from_offchain: bool,
712 // Set once we've signed a holder commitment transaction and handed it over to our
713 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
714 // may occur, and we fail any such monitor updates.
716 // In case of update rejection due to a locally already signed commitment transaction, we
717 // nevertheless store update content to track in case of concurrent broadcast by another
718 // remote monitor out-of-order with regards to the block view.
719 holder_tx_signed: bool,
721 funding_spend_confirmed: Option<Txid>,
722 /// The set of HTLCs which have been either claimed or failed on chain and have reached
723 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
724 /// spending CSV for revocable outputs).
725 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
727 // We simply modify best_block in Channel's block_connected so that serialization is
728 // consistent but hopefully the users' copy handles block_connected in a consistent way.
729 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
730 // their best_block from its state and not based on updated copies that didn't run through
731 // the full block_connected).
732 best_block: BestBlock,
734 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
737 /// Transaction outputs to watch for on-chain spends.
738 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
740 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
741 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
742 /// underlying object
743 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
744 fn eq(&self, other: &Self) -> bool {
745 let inner = self.inner.lock().unwrap();
746 let other = other.inner.lock().unwrap();
751 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
752 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
753 /// underlying object
754 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
755 fn eq(&self, other: &Self) -> bool {
756 if self.latest_update_id != other.latest_update_id ||
757 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
758 self.destination_script != other.destination_script ||
759 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
760 self.counterparty_payment_script != other.counterparty_payment_script ||
761 self.channel_keys_id != other.channel_keys_id ||
762 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
763 self.funding_info != other.funding_info ||
764 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
765 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
766 self.counterparty_commitment_params != other.counterparty_commitment_params ||
767 self.funding_redeemscript != other.funding_redeemscript ||
768 self.channel_value_satoshis != other.channel_value_satoshis ||
769 self.their_cur_revocation_points != other.their_cur_revocation_points ||
770 self.on_holder_tx_csv != other.on_holder_tx_csv ||
771 self.commitment_secrets != other.commitment_secrets ||
772 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
773 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
774 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
775 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
776 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
777 self.current_holder_commitment_number != other.current_holder_commitment_number ||
778 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
779 self.payment_preimages != other.payment_preimages ||
780 self.pending_monitor_events != other.pending_monitor_events ||
781 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
782 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
783 self.outputs_to_watch != other.outputs_to_watch ||
784 self.lockdown_from_offchain != other.lockdown_from_offchain ||
785 self.holder_tx_signed != other.holder_tx_signed ||
786 self.funding_spend_confirmed != other.funding_spend_confirmed ||
787 self.htlcs_resolved_on_chain != other.htlcs_resolved_on_chain
796 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
797 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
798 self.inner.lock().unwrap().write(writer)
802 // These are also used for ChannelMonitorUpdate, above.
803 const SERIALIZATION_VERSION: u8 = 1;
804 const MIN_SERIALIZATION_VERSION: u8 = 1;
806 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
807 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
808 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
810 self.latest_update_id.write(writer)?;
812 // Set in initial Channel-object creation, so should always be set by now:
813 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
815 self.destination_script.write(writer)?;
816 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
817 writer.write_all(&[0; 1])?;
818 broadcasted_holder_revokable_script.0.write(writer)?;
819 broadcasted_holder_revokable_script.1.write(writer)?;
820 broadcasted_holder_revokable_script.2.write(writer)?;
822 writer.write_all(&[1; 1])?;
825 self.counterparty_payment_script.write(writer)?;
826 match &self.shutdown_script {
827 Some(script) => script.write(writer)?,
828 None => Script::new().write(writer)?,
831 self.channel_keys_id.write(writer)?;
832 self.holder_revocation_basepoint.write(writer)?;
833 writer.write_all(&self.funding_info.0.txid[..])?;
834 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
835 self.funding_info.1.write(writer)?;
836 self.current_counterparty_commitment_txid.write(writer)?;
837 self.prev_counterparty_commitment_txid.write(writer)?;
839 self.counterparty_commitment_params.write(writer)?;
840 self.funding_redeemscript.write(writer)?;
841 self.channel_value_satoshis.write(writer)?;
843 match self.their_cur_revocation_points {
844 Some((idx, pubkey, second_option)) => {
845 writer.write_all(&byte_utils::be48_to_array(idx))?;
846 writer.write_all(&pubkey.serialize())?;
847 match second_option {
848 Some(second_pubkey) => {
849 writer.write_all(&second_pubkey.serialize())?;
852 writer.write_all(&[0; 33])?;
857 writer.write_all(&byte_utils::be48_to_array(0))?;
861 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
863 self.commitment_secrets.write(writer)?;
865 macro_rules! serialize_htlc_in_commitment {
866 ($htlc_output: expr) => {
867 writer.write_all(&[$htlc_output.offered as u8; 1])?;
868 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
869 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
870 writer.write_all(&$htlc_output.payment_hash.0[..])?;
871 $htlc_output.transaction_output_index.write(writer)?;
875 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
876 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
877 writer.write_all(&txid[..])?;
878 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
879 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
880 serialize_htlc_in_commitment!(htlc_output);
881 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
885 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
886 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
887 writer.write_all(&txid[..])?;
888 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
891 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
892 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
893 writer.write_all(&payment_hash.0[..])?;
894 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
897 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
898 writer.write_all(&[1; 1])?;
899 prev_holder_tx.write(writer)?;
901 writer.write_all(&[0; 1])?;
904 self.current_holder_commitment_tx.write(writer)?;
906 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
907 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
909 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
910 for payment_preimage in self.payment_preimages.values() {
911 writer.write_all(&payment_preimage.0[..])?;
914 writer.write_all(&byte_utils::be64_to_array(self.pending_monitor_events.len() as u64))?;
915 for event in self.pending_monitor_events.iter() {
917 MonitorEvent::HTLCEvent(upd) => {
921 MonitorEvent::CommitmentTxBroadcasted(_) => 1u8.write(writer)?
925 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
926 for event in self.pending_events.iter() {
927 event.write(writer)?;
930 self.best_block.block_hash().write(writer)?;
931 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
933 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
934 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
935 entry.write(writer)?;
938 (self.outputs_to_watch.len() as u64).write(writer)?;
939 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
941 (idx_scripts.len() as u64).write(writer)?;
942 for (idx, script) in idx_scripts.iter() {
944 script.write(writer)?;
947 self.onchain_tx_handler.write(writer)?;
949 self.lockdown_from_offchain.write(writer)?;
950 self.holder_tx_signed.write(writer)?;
952 write_tlv_fields!(writer, {
953 (1, self.funding_spend_confirmed, option),
954 (3, self.htlcs_resolved_on_chain, vec_type),
961 impl<Signer: Sign> ChannelMonitor<Signer> {
962 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
963 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
964 channel_parameters: &ChannelTransactionParameters,
965 funding_redeemscript: Script, channel_value_satoshis: u64,
966 commitment_transaction_number_obscure_factor: u64,
967 initial_holder_commitment_tx: HolderCommitmentTransaction,
968 best_block: BestBlock) -> ChannelMonitor<Signer> {
970 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
971 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
972 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
974 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
975 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
976 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
977 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
979 let channel_keys_id = keys.channel_keys_id();
980 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
982 // block for Rust 1.34 compat
983 let (holder_commitment_tx, current_holder_commitment_number) = {
984 let trusted_tx = initial_holder_commitment_tx.trust();
985 let txid = trusted_tx.txid();
987 let tx_keys = trusted_tx.keys();
988 let holder_commitment_tx = HolderSignedTx {
990 revocation_key: tx_keys.revocation_key,
991 a_htlc_key: tx_keys.broadcaster_htlc_key,
992 b_htlc_key: tx_keys.countersignatory_htlc_key,
993 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
994 per_commitment_point: tx_keys.per_commitment_point,
995 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
996 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
997 feerate_per_kw: trusted_tx.feerate_per_kw(),
999 (holder_commitment_tx, trusted_tx.commitment_number())
1002 let onchain_tx_handler =
1003 OnchainTxHandler::new(destination_script.clone(), keys,
1004 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
1006 let mut outputs_to_watch = HashMap::new();
1007 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1010 inner: Mutex::new(ChannelMonitorImpl {
1011 latest_update_id: 0,
1012 commitment_transaction_number_obscure_factor,
1014 destination_script: destination_script.clone(),
1015 broadcasted_holder_revokable_script: None,
1016 counterparty_payment_script,
1020 holder_revocation_basepoint,
1022 current_counterparty_commitment_txid: None,
1023 prev_counterparty_commitment_txid: None,
1025 counterparty_commitment_params,
1026 funding_redeemscript,
1027 channel_value_satoshis,
1028 their_cur_revocation_points: None,
1030 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1032 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1033 counterparty_claimable_outpoints: HashMap::new(),
1034 counterparty_commitment_txn_on_chain: HashMap::new(),
1035 counterparty_hash_commitment_number: HashMap::new(),
1037 prev_holder_signed_commitment_tx: None,
1038 current_holder_commitment_tx: holder_commitment_tx,
1039 current_counterparty_commitment_number: 1 << 48,
1040 current_holder_commitment_number,
1042 payment_preimages: HashMap::new(),
1043 pending_monitor_events: Vec::new(),
1044 pending_events: Vec::new(),
1046 onchain_events_awaiting_threshold_conf: Vec::new(),
1051 lockdown_from_offchain: false,
1052 holder_tx_signed: false,
1053 funding_spend_confirmed: None,
1054 htlcs_resolved_on_chain: Vec::new(),
1064 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1065 self.inner.lock().unwrap().provide_secret(idx, secret)
1068 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1069 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1070 /// possibly future revocation/preimage information) to claim outputs where possible.
1071 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1072 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1075 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1076 commitment_number: u64,
1077 their_revocation_point: PublicKey,
1079 ) where L::Target: Logger {
1080 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1081 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
1085 fn provide_latest_holder_commitment_tx(
1087 holder_commitment_tx: HolderCommitmentTransaction,
1088 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1089 ) -> Result<(), MonitorUpdateError> {
1090 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
1091 holder_commitment_tx, htlc_outputs)
1095 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1097 payment_hash: &PaymentHash,
1098 payment_preimage: &PaymentPreimage,
1103 B::Target: BroadcasterInterface,
1104 F::Target: FeeEstimator,
1107 self.inner.lock().unwrap().provide_payment_preimage(
1108 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1111 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
1116 B::Target: BroadcasterInterface,
1119 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
1122 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1125 /// panics if the given update is not the next update by update_id.
1126 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1128 updates: &ChannelMonitorUpdate,
1132 ) -> Result<(), MonitorUpdateError>
1134 B::Target: BroadcasterInterface,
1135 F::Target: FeeEstimator,
1138 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1141 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1143 pub fn get_latest_update_id(&self) -> u64 {
1144 self.inner.lock().unwrap().get_latest_update_id()
1147 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1148 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1149 self.inner.lock().unwrap().get_funding_txo().clone()
1152 /// Gets a list of txids, with their output scripts (in the order they appear in the
1153 /// transaction), which we must learn about spends of via block_connected().
1154 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1155 self.inner.lock().unwrap().get_outputs_to_watch()
1156 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1159 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1160 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1161 /// have been registered.
1162 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1163 let lock = self.inner.lock().unwrap();
1164 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1165 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1166 for (index, script_pubkey) in outputs.iter() {
1167 assert!(*index <= u16::max_value() as u32);
1168 filter.register_output(WatchedOutput {
1170 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1171 script_pubkey: script_pubkey.clone(),
1177 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1178 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1179 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1180 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1183 /// Gets the list of pending events which were generated by previous actions, clearing the list
1186 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1187 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1188 /// no internal locking in ChannelMonitors.
1189 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1190 self.inner.lock().unwrap().get_and_clear_pending_events()
1193 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1194 self.inner.lock().unwrap().get_min_seen_secret()
1197 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1198 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1201 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1202 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1205 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1206 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1207 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1208 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1209 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1210 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1211 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1212 /// out-of-band the other node operator to coordinate with him if option is available to you.
1213 /// In any-case, choice is up to the user.
1214 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1215 where L::Target: Logger {
1216 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1219 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1220 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1221 /// revoked commitment transaction.
1222 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1223 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1224 where L::Target: Logger {
1225 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1228 /// Processes transactions in a newly connected block, which may result in any of the following:
1229 /// - update the monitor's state against resolved HTLCs
1230 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1231 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1232 /// - detect settled outputs for later spending
1233 /// - schedule and bump any in-flight claims
1235 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1236 /// [`get_outputs_to_watch`].
1238 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1239 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1241 header: &BlockHeader,
1242 txdata: &TransactionData,
1247 ) -> Vec<TransactionOutputs>
1249 B::Target: BroadcasterInterface,
1250 F::Target: FeeEstimator,
1253 self.inner.lock().unwrap().block_connected(
1254 header, txdata, height, broadcaster, fee_estimator, logger)
1257 /// Determines if the disconnected block contained any transactions of interest and updates
1259 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1261 header: &BlockHeader,
1267 B::Target: BroadcasterInterface,
1268 F::Target: FeeEstimator,
1271 self.inner.lock().unwrap().block_disconnected(
1272 header, height, broadcaster, fee_estimator, logger)
1275 /// Processes transactions confirmed in a block with the given header and height, returning new
1276 /// outputs to watch. See [`block_connected`] for details.
1278 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1279 /// blocks. See [`chain::Confirm`] for calling expectations.
1281 /// [`block_connected`]: Self::block_connected
1282 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1284 header: &BlockHeader,
1285 txdata: &TransactionData,
1290 ) -> Vec<TransactionOutputs>
1292 B::Target: BroadcasterInterface,
1293 F::Target: FeeEstimator,
1296 self.inner.lock().unwrap().transactions_confirmed(
1297 header, txdata, height, broadcaster, fee_estimator, logger)
1300 /// Processes a transaction that was reorganized out of the chain.
1302 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1303 /// than blocks. See [`chain::Confirm`] for calling expectations.
1305 /// [`block_disconnected`]: Self::block_disconnected
1306 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1313 B::Target: BroadcasterInterface,
1314 F::Target: FeeEstimator,
1317 self.inner.lock().unwrap().transaction_unconfirmed(
1318 txid, broadcaster, fee_estimator, logger);
1321 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1322 /// [`block_connected`] for details.
1324 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1325 /// blocks. See [`chain::Confirm`] for calling expectations.
1327 /// [`block_connected`]: Self::block_connected
1328 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1330 header: &BlockHeader,
1335 ) -> Vec<TransactionOutputs>
1337 B::Target: BroadcasterInterface,
1338 F::Target: FeeEstimator,
1341 self.inner.lock().unwrap().best_block_updated(
1342 header, height, broadcaster, fee_estimator, logger)
1345 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1346 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1347 let inner = self.inner.lock().unwrap();
1348 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1350 .map(|entry| entry.txid)
1351 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1353 txids.sort_unstable();
1358 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1359 /// [`chain::Confirm`] interfaces.
1360 pub fn current_best_block(&self) -> BestBlock {
1361 self.inner.lock().unwrap().best_block.clone()
1364 /// Gets the balances in this channel which are either claimable by us if we were to
1365 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1368 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1369 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1370 /// balance, or until our counterparty has claimed the balance and accrued several
1371 /// confirmations on the claim transaction.
1373 /// Note that the balances available when you or your counterparty have broadcasted revoked
1374 /// state(s) may not be fully captured here.
1377 /// See [`Balance`] for additional details on the types of claimable balances which
1378 /// may be returned here and their meanings.
1379 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1380 let mut res = Vec::new();
1381 let us = self.inner.lock().unwrap();
1383 let mut confirmed_txid = us.funding_spend_confirmed;
1384 let mut pending_commitment_tx_conf_thresh = None;
1385 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1386 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1387 Some((event.txid, event.confirmation_threshold()))
1390 if let Some((txid, conf_thresh)) = funding_spend_pending {
1391 debug_assert!(us.funding_spend_confirmed.is_none(),
1392 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1393 confirmed_txid = Some(txid);
1394 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1397 macro_rules! walk_htlcs {
1398 ($holder_commitment: expr, $htlc_iter: expr) => {
1399 for htlc in $htlc_iter {
1400 if let Some(htlc_input_idx) = htlc.transaction_output_index {
1401 if us.htlcs_resolved_on_chain.iter().any(|v| v.input_idx == htlc_input_idx) {
1402 assert!(us.funding_spend_confirmed.is_some());
1403 } else if htlc.offered == $holder_commitment {
1404 // If the payment was outbound, check if there's an HTLCUpdate
1405 // indicating we have spent this HTLC with a timeout, claiming it back
1406 // and awaiting confirmations on it.
1407 let htlc_update_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1408 if let OnchainEvent::HTLCUpdate { input_idx: Some(input_idx), .. } = event.event {
1409 if input_idx == htlc_input_idx { Some(event.confirmation_threshold()) } else { None }
1412 if let Some(conf_thresh) = htlc_update_pending {
1413 res.push(Balance::ClaimableAwaitingConfirmations {
1414 claimable_amount_satoshis: htlc.amount_msat / 1000,
1415 confirmation_height: conf_thresh,
1418 res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
1419 claimable_amount_satoshis: htlc.amount_msat / 1000,
1420 claimable_height: htlc.cltv_expiry,
1423 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1424 // Otherwise (the payment was inbound), only expose it as claimable if
1425 // we know the preimage.
1426 // Note that if there is a pending claim, but it did not use the
1427 // preimage, we lost funds to our counterparty! We will then continue
1428 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1429 let htlc_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1430 if let OnchainEvent::HTLCSpendConfirmation { input_idx, preimage, .. } = event.event {
1431 if input_idx == htlc_input_idx {
1432 Some((event.confirmation_threshold(), preimage.is_some()))
1436 if let Some((conf_thresh, true)) = htlc_spend_pending {
1437 res.push(Balance::ClaimableAwaitingConfirmations {
1438 claimable_amount_satoshis: htlc.amount_msat / 1000,
1439 confirmation_height: conf_thresh,
1442 res.push(Balance::ContentiousClaimable {
1443 claimable_amount_satoshis: htlc.amount_msat / 1000,
1444 timeout_height: htlc.cltv_expiry,
1453 if let Some(txid) = confirmed_txid {
1454 let mut found_commitment_tx = false;
1455 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1456 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().map(|(a, _)| a));
1457 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1458 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1459 if let OnchainEvent::MaturingOutput {
1460 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1462 Some(descriptor.output.value)
1465 res.push(Balance::ClaimableAwaitingConfirmations {
1466 claimable_amount_satoshis: value,
1467 confirmation_height: conf_thresh,
1470 // If a counterparty commitment transaction is awaiting confirmation, we
1471 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1472 // confirmation with the same height or have never met our dust amount.
1475 found_commitment_tx = true;
1476 } else if txid == us.current_holder_commitment_tx.txid {
1477 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1478 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1479 res.push(Balance::ClaimableAwaitingConfirmations {
1480 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1481 confirmation_height: conf_thresh,
1484 found_commitment_tx = true;
1485 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1486 if txid == prev_commitment.txid {
1487 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1488 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1489 res.push(Balance::ClaimableAwaitingConfirmations {
1490 claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1491 confirmation_height: conf_thresh,
1494 found_commitment_tx = true;
1497 if !found_commitment_tx {
1498 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1499 // We blindly assume this is a cooperative close transaction here, and that
1500 // neither us nor our counterparty misbehaved. At worst we've under-estimated
1501 // the amount we can claim as we'll punish a misbehaving counterparty.
1502 res.push(Balance::ClaimableAwaitingConfirmations {
1503 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1504 confirmation_height: conf_thresh,
1508 // TODO: Add logic to provide claimable balances for counterparty broadcasting revoked
1511 let mut claimable_inbound_htlc_value_sat = 0;
1512 for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1513 if htlc.transaction_output_index.is_none() { continue; }
1515 res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
1516 claimable_amount_satoshis: htlc.amount_msat / 1000,
1517 claimable_height: htlc.cltv_expiry,
1519 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1520 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1523 res.push(Balance::ClaimableOnChannelClose {
1524 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1532 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
1533 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
1534 /// after ANTI_REORG_DELAY blocks.
1536 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
1537 /// are the commitment transactions which are generated by us. The off-chain state machine in
1538 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
1539 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
1540 /// included in a remote commitment transaction are failed back if they are not present in the
1541 /// broadcasted commitment transaction.
1543 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
1544 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
1545 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
1546 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
1547 macro_rules! fail_unbroadcast_htlcs {
1548 ($self: expr, $commitment_tx_type: expr, $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
1549 macro_rules! check_htlc_fails {
1550 ($txid: expr, $commitment_tx: expr) => {
1551 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
1552 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1553 if let &Some(ref source) = source_option {
1554 // Check if the HTLC is present in the commitment transaction that was
1555 // broadcast, but not if it was below the dust limit, which we should
1556 // fail backwards immediately as there is no way for us to learn the
1557 // payment_preimage.
1558 // Note that if the dust limit were allowed to change between
1559 // commitment transactions we'd want to be check whether *any*
1560 // broadcastable commitment transaction has the HTLC in it, but it
1561 // cannot currently change after channel initialization, so we don't
1563 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
1564 let mut matched_htlc = false;
1565 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
1566 if broadcast_htlc.transaction_output_index.is_some() && Some(&**source) == *broadcast_source {
1567 matched_htlc = true;
1571 if matched_htlc { continue; }
1572 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1573 if entry.height != $commitment_tx_conf_height { return true; }
1575 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1576 *update_source != **source
1581 let entry = OnchainEventEntry {
1583 height: $commitment_tx_conf_height,
1584 event: OnchainEvent::HTLCUpdate {
1585 source: (**source).clone(),
1586 payment_hash: htlc.payment_hash.clone(),
1587 onchain_value_satoshis: Some(htlc.amount_msat / 1000),
1591 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction, waiting for confirmation (at height {})",
1592 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type, entry.confirmation_threshold());
1593 $self.onchain_events_awaiting_threshold_conf.push(entry);
1599 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
1600 check_htlc_fails!(txid, "current");
1602 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
1603 check_htlc_fails!(txid, "previous");
1608 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1609 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1610 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1611 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1612 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1613 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1614 return Err(MonitorUpdateError("Previous secret did not match new one"));
1617 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1618 // events for now-revoked/fulfilled HTLCs.
1619 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1620 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1625 if !self.payment_preimages.is_empty() {
1626 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1627 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1628 let min_idx = self.get_min_seen_secret();
1629 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1631 self.payment_preimages.retain(|&k, _| {
1632 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1633 if k == htlc.payment_hash {
1637 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1638 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1639 if k == htlc.payment_hash {
1644 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1651 counterparty_hash_commitment_number.remove(&k);
1660 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_revocation_point: PublicKey, logger: &L) where L::Target: Logger {
1661 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1662 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1663 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1665 for &(ref htlc, _) in &htlc_outputs {
1666 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1669 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1670 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1671 self.current_counterparty_commitment_txid = Some(txid);
1672 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1673 self.current_counterparty_commitment_number = commitment_number;
1674 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1675 match self.their_cur_revocation_points {
1676 Some(old_points) => {
1677 if old_points.0 == commitment_number + 1 {
1678 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1679 } else if old_points.0 == commitment_number + 2 {
1680 if let Some(old_second_point) = old_points.2 {
1681 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1683 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1686 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1690 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1693 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1694 for htlc in htlc_outputs {
1695 if htlc.0.transaction_output_index.is_some() {
1701 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1702 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1703 /// is important that any clones of this channel monitor (including remote clones) by kept
1704 /// up-to-date as our holder commitment transaction is updated.
1705 /// Panics if set_on_holder_tx_csv has never been called.
1706 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1707 // block for Rust 1.34 compat
1708 let mut new_holder_commitment_tx = {
1709 let trusted_tx = holder_commitment_tx.trust();
1710 let txid = trusted_tx.txid();
1711 let tx_keys = trusted_tx.keys();
1712 self.current_holder_commitment_number = trusted_tx.commitment_number();
1715 revocation_key: tx_keys.revocation_key,
1716 a_htlc_key: tx_keys.broadcaster_htlc_key,
1717 b_htlc_key: tx_keys.countersignatory_htlc_key,
1718 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1719 per_commitment_point: tx_keys.per_commitment_point,
1721 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
1722 feerate_per_kw: trusted_tx.feerate_per_kw(),
1725 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1726 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1727 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1728 if self.holder_tx_signed {
1729 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1734 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1735 /// commitment_tx_infos which contain the payment hash have been revoked.
1736 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(&mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B, fee_estimator: &F, logger: &L)
1737 where B::Target: BroadcasterInterface,
1738 F::Target: FeeEstimator,
1741 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1743 // If the channel is force closed, try to claim the output from this preimage.
1744 // First check if a counterparty commitment transaction has been broadcasted:
1745 macro_rules! claim_htlcs {
1746 ($commitment_number: expr, $txid: expr) => {
1747 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1748 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1751 if let Some(txid) = self.current_counterparty_commitment_txid {
1752 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1753 claim_htlcs!(*commitment_number, txid);
1757 if let Some(txid) = self.prev_counterparty_commitment_txid {
1758 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1759 claim_htlcs!(*commitment_number, txid);
1764 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1765 // claiming the HTLC output from each of the holder commitment transactions.
1766 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1767 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1768 // holder commitment transactions.
1769 if self.broadcasted_holder_revokable_script.is_some() {
1770 // Assume that the broadcasted commitment transaction confirmed in the current best
1771 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
1773 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
1774 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1775 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1776 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
1777 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1782 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1783 where B::Target: BroadcasterInterface,
1786 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1787 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
1788 broadcaster.broadcast_transaction(tx);
1790 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
1793 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1794 where B::Target: BroadcasterInterface,
1795 F::Target: FeeEstimator,
1798 // ChannelMonitor updates may be applied after force close if we receive a
1799 // preimage for a broadcasted commitment transaction HTLC output that we'd
1800 // like to claim on-chain. If this is the case, we no longer have guaranteed
1801 // access to the monitor's update ID, so we use a sentinel value instead.
1802 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1803 match updates.updates[0] {
1804 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1805 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1807 assert_eq!(updates.updates.len(), 1);
1808 } else if self.latest_update_id + 1 != updates.update_id {
1809 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1811 for update in updates.updates.iter() {
1813 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1814 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1815 if self.lockdown_from_offchain { panic!(); }
1816 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1818 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1819 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1820 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1822 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1823 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1824 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1826 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1827 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1828 self.provide_secret(*idx, *secret)?
1830 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1831 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1832 self.lockdown_from_offchain = true;
1833 if *should_broadcast {
1834 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1835 } else if !self.holder_tx_signed {
1836 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");
1838 // If we generated a MonitorEvent::CommitmentTxBroadcasted, the ChannelManager
1839 // will still give us a ChannelForceClosed event with !should_broadcast, but we
1840 // shouldn't print the scary warning above.
1841 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
1844 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
1845 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
1846 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
1847 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
1852 self.latest_update_id = updates.update_id;
1856 pub fn get_latest_update_id(&self) -> u64 {
1857 self.latest_update_id
1860 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1864 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1865 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1866 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1867 // its trivial to do, double-check that here.
1868 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1869 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1871 &self.outputs_to_watch
1874 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1875 let mut ret = Vec::new();
1876 mem::swap(&mut ret, &mut self.pending_monitor_events);
1880 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1881 let mut ret = Vec::new();
1882 mem::swap(&mut ret, &mut self.pending_events);
1886 /// Can only fail if idx is < get_min_seen_secret
1887 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1888 self.commitment_secrets.get_secret(idx)
1891 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1892 self.commitment_secrets.get_min_seen_secret()
1895 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1896 self.current_counterparty_commitment_number
1899 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1900 self.current_holder_commitment_number
1903 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1904 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1905 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1906 /// HTLC-Success/HTLC-Timeout transactions.
1907 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1908 /// revoked counterparty commitment tx
1909 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1910 // Most secp and related errors trying to create keys means we have no hope of constructing
1911 // a spend transaction...so we return no transactions to broadcast
1912 let mut claimable_outpoints = Vec::new();
1913 let mut watch_outputs = Vec::new();
1915 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1916 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1918 macro_rules! ignore_error {
1919 ( $thing : expr ) => {
1922 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1927 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence as u64 & 0xffffff) << 3*8) | (tx.lock_time as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
1928 if commitment_number >= self.get_min_seen_secret() {
1929 let secret = self.get_secret(commitment_number).unwrap();
1930 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1931 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1932 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1933 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));
1935 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
1936 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1938 // First, process non-htlc outputs (to_holder & to_counterparty)
1939 for (idx, outp) in tx.output.iter().enumerate() {
1940 if outp.script_pubkey == revokeable_p2wsh {
1941 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);
1942 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);
1943 claimable_outpoints.push(justice_package);
1947 // Then, try to find revoked htlc outputs
1948 if let Some(ref per_commitment_data) = per_commitment_option {
1949 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1950 if let Some(transaction_output_index) = htlc.transaction_output_index {
1951 if transaction_output_index as usize >= tx.output.len() ||
1952 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1953 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1955 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());
1956 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
1957 claimable_outpoints.push(justice_package);
1962 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1963 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1964 // We're definitely a counterparty commitment transaction!
1965 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1966 for (idx, outp) in tx.output.iter().enumerate() {
1967 watch_outputs.push((idx as u32, outp.clone()));
1969 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1971 fail_unbroadcast_htlcs!(self, "revoked counterparty", height, [].iter().map(|a| *a), logger);
1973 } else if let Some(per_commitment_data) = per_commitment_option {
1974 // While this isn't useful yet, there is a potential race where if a counterparty
1975 // revokes a state at the same time as the commitment transaction for that state is
1976 // confirmed, and the watchtower receives the block before the user, the user could
1977 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1978 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1979 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1981 for (idx, outp) in tx.output.iter().enumerate() {
1982 watch_outputs.push((idx as u32, outp.clone()));
1984 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1986 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1987 fail_unbroadcast_htlcs!(self, "counterparty", height, per_commitment_data.iter().map(|(a, b)| (a, b.as_ref().map(|b| b.as_ref()))), logger);
1989 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1990 for req in htlc_claim_reqs {
1991 claimable_outpoints.push(req);
1995 (claimable_outpoints, (commitment_txid, watch_outputs))
1998 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<PackageTemplate> {
1999 let mut claimable_outpoints = Vec::new();
2000 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
2001 if let Some(revocation_points) = self.their_cur_revocation_points {
2002 let revocation_point_option =
2003 // If the counterparty commitment tx is the latest valid state, use their latest
2004 // per-commitment point
2005 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
2006 else if let Some(point) = revocation_points.2.as_ref() {
2007 // If counterparty commitment tx is the state previous to the latest valid state, use
2008 // their previous per-commitment point (non-atomicity of revocation means it's valid for
2009 // them to temporarily have two valid commitment txns from our viewpoint)
2010 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
2012 if let Some(revocation_point) = revocation_point_option {
2013 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
2014 if let Some(transaction_output_index) = htlc.transaction_output_index {
2015 if let Some(transaction) = tx {
2016 if transaction_output_index as usize >= transaction.output.len() ||
2017 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2018 return claimable_outpoints; // Corrupted per_commitment_data, fuck this user
2021 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
2022 if preimage.is_some() || !htlc.offered {
2023 let counterparty_htlc_outp = if htlc.offered { PackageSolvingData::CounterpartyOfferedHTLCOutput(CounterpartyOfferedHTLCOutput::build(*revocation_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, preimage.unwrap(), htlc.clone())) } else { PackageSolvingData::CounterpartyReceivedHTLCOutput(CounterpartyReceivedHTLCOutput::build(*revocation_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, htlc.clone())) };
2024 let aggregation = if !htlc.offered { false } else { true };
2025 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
2026 claimable_outpoints.push(counterparty_package);
2036 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2037 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 {
2038 let htlc_txid = tx.txid();
2039 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
2040 return (Vec::new(), None)
2043 macro_rules! ignore_error {
2044 ( $thing : expr ) => {
2047 Err(_) => return (Vec::new(), None)
2052 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2053 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2054 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
2056 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, 0);
2057 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);
2058 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);
2059 let claimable_outpoints = vec!(justice_package);
2060 let outputs = vec![(0, tx.output[0].clone())];
2061 (claimable_outpoints, Some((htlc_txid, outputs)))
2064 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
2065 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2066 // script so we can detect whether a holder transaction has been seen on-chain.
2067 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2068 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2070 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2071 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2073 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2074 if let Some(transaction_output_index) = htlc.transaction_output_index {
2075 let htlc_output = if htlc.offered {
2076 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
2078 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2081 // We can't build an HTLC-Success transaction without the preimage
2084 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
2086 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), htlc.cltv_expiry, false, conf_height);
2087 claim_requests.push(htlc_package);
2091 (claim_requests, broadcasted_holder_revokable_script)
2094 // Returns holder HTLC outputs to watch and react to in case of spending.
2095 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2096 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2097 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2098 if let Some(transaction_output_index) = htlc.transaction_output_index {
2099 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2105 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2106 /// revoked using data in holder_claimable_outpoints.
2107 /// Should not be used if check_spend_revoked_transaction succeeds.
2108 /// Returns None unless the transaction is definitely one of our commitment transactions.
2109 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
2110 let commitment_txid = tx.txid();
2111 let mut claim_requests = Vec::new();
2112 let mut watch_outputs = Vec::new();
2114 macro_rules! append_onchain_update {
2115 ($updates: expr, $to_watch: expr) => {
2116 claim_requests = $updates.0;
2117 self.broadcasted_holder_revokable_script = $updates.1;
2118 watch_outputs.append(&mut $to_watch);
2122 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2123 let mut is_holder_tx = false;
2125 if self.current_holder_commitment_tx.txid == commitment_txid {
2126 is_holder_tx = true;
2127 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2128 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2129 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2130 append_onchain_update!(res, to_watch);
2131 fail_unbroadcast_htlcs!(self, "latest holder", height, self.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
2132 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2133 if holder_tx.txid == commitment_txid {
2134 is_holder_tx = true;
2135 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2136 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2137 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2138 append_onchain_update!(res, to_watch);
2139 fail_unbroadcast_htlcs!(self, "previous holder", height, holder_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
2144 Some((claim_requests, (commitment_txid, watch_outputs)))
2150 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2151 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2152 self.holder_tx_signed = true;
2153 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2154 let txid = commitment_tx.txid();
2155 let mut holder_transactions = vec![commitment_tx];
2156 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2157 if let Some(vout) = htlc.0.transaction_output_index {
2158 let preimage = if !htlc.0.offered {
2159 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2160 // We can't build an HTLC-Success transaction without the preimage
2163 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2164 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2165 // current locktime requirements on-chain. We will broadcast them in
2166 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2167 // Note that we add + 1 as transactions are broadcastable when they can be
2168 // confirmed in the next block.
2171 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2172 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2173 holder_transactions.push(htlc_tx);
2177 // 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.
2178 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2182 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2183 /// Note that this includes possibly-locktimed-in-the-future transactions!
2184 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2185 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2186 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2187 let txid = commitment_tx.txid();
2188 let mut holder_transactions = vec![commitment_tx];
2189 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2190 if let Some(vout) = htlc.0.transaction_output_index {
2191 let preimage = if !htlc.0.offered {
2192 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2193 // We can't build an HTLC-Success transaction without the preimage
2197 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
2198 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2199 holder_transactions.push(htlc_tx);
2206 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>
2207 where B::Target: BroadcasterInterface,
2208 F::Target: FeeEstimator,
2211 let block_hash = header.block_hash();
2212 self.best_block = BestBlock::new(block_hash, height);
2214 self.transactions_confirmed(header, txdata, height, broadcaster, fee_estimator, logger)
2217 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
2219 header: &BlockHeader,
2224 ) -> Vec<TransactionOutputs>
2226 B::Target: BroadcasterInterface,
2227 F::Target: FeeEstimator,
2230 let block_hash = header.block_hash();
2232 if height > self.best_block.height() {
2233 self.best_block = BestBlock::new(block_hash, height);
2234 self.block_confirmed(height, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
2235 } else if block_hash != self.best_block.block_hash() {
2236 self.best_block = BestBlock::new(block_hash, height);
2237 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
2238 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
2240 } else { Vec::new() }
2243 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
2245 header: &BlockHeader,
2246 txdata: &TransactionData,
2251 ) -> Vec<TransactionOutputs>
2253 B::Target: BroadcasterInterface,
2254 F::Target: FeeEstimator,
2257 let txn_matched = self.filter_block(txdata);
2258 for tx in &txn_matched {
2259 let mut output_val = 0;
2260 for out in tx.output.iter() {
2261 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2262 output_val += out.value;
2263 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2267 let block_hash = header.block_hash();
2269 let mut watch_outputs = Vec::new();
2270 let mut claimable_outpoints = Vec::new();
2271 for tx in &txn_matched {
2272 if tx.input.len() == 1 {
2273 // Assuming our keys were not leaked (in which case we're screwed no matter what),
2274 // commitment transactions and HTLC transactions will all only ever have one input,
2275 // which is an easy way to filter out any potential non-matching txn for lazy
2277 let prevout = &tx.input[0].previous_output;
2278 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
2279 let mut balance_spendable_csv = None;
2280 log_info!(logger, "Channel closed by funding output spend in txid {}.", log_bytes!(tx.txid()));
2281 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
2282 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
2283 if !new_outputs.1.is_empty() {
2284 watch_outputs.push(new_outputs);
2286 claimable_outpoints.append(&mut new_outpoints);
2287 if new_outpoints.is_empty() {
2288 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &logger) {
2289 if !new_outputs.1.is_empty() {
2290 watch_outputs.push(new_outputs);
2292 claimable_outpoints.append(&mut new_outpoints);
2293 balance_spendable_csv = Some(self.on_holder_tx_csv);
2297 let txid = tx.txid();
2298 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2301 event: OnchainEvent::FundingSpendConfirmation {
2302 on_local_output_csv: balance_spendable_csv,
2306 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
2307 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
2308 claimable_outpoints.append(&mut new_outpoints);
2309 if let Some(new_outputs) = new_outputs_option {
2310 watch_outputs.push(new_outputs);
2315 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2316 // can also be resolved in a few other ways which can have more than one output. Thus,
2317 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2318 self.is_resolving_htlc_output(&tx, height, &logger);
2320 self.is_paying_spendable_output(&tx, height, &logger);
2323 if height > self.best_block.height() {
2324 self.best_block = BestBlock::new(block_hash, height);
2327 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
2330 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
2331 /// `self.best_block` before calling if a new best blockchain tip is available. More
2332 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
2333 /// complexity especially in `OnchainTx::update_claims_view`.
2335 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
2336 /// confirmed at, even if it is not the current best height.
2337 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
2340 txn_matched: Vec<&Transaction>,
2341 mut watch_outputs: Vec<TransactionOutputs>,
2342 mut claimable_outpoints: Vec<PackageTemplate>,
2346 ) -> Vec<TransactionOutputs>
2348 B::Target: BroadcasterInterface,
2349 F::Target: FeeEstimator,
2352 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
2353 debug_assert!(self.best_block.height() >= conf_height);
2355 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
2356 if should_broadcast {
2357 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2358 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());
2359 claimable_outpoints.push(commitment_package);
2360 self.pending_monitor_events.push(MonitorEvent::CommitmentTxBroadcasted(self.funding_info.0));
2361 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2362 self.holder_tx_signed = true;
2363 // Because we're broadcasting a commitment transaction, we should construct the package
2364 // assuming it gets confirmed in the next block. Sadly, we have code which considers
2365 // "not yet confirmed" things as discardable, so we cannot do that here.
2366 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2367 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2368 if !new_outputs.is_empty() {
2369 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2371 claimable_outpoints.append(&mut new_outpoints);
2374 // Find which on-chain events have reached their confirmation threshold.
2375 let onchain_events_awaiting_threshold_conf =
2376 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2377 let mut onchain_events_reaching_threshold_conf = Vec::new();
2378 for entry in onchain_events_awaiting_threshold_conf {
2379 if entry.has_reached_confirmation_threshold(&self.best_block) {
2380 onchain_events_reaching_threshold_conf.push(entry);
2382 self.onchain_events_awaiting_threshold_conf.push(entry);
2386 // Used to check for duplicate HTLC resolutions.
2387 #[cfg(debug_assertions)]
2388 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2390 .filter_map(|entry| match &entry.event {
2391 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2395 #[cfg(debug_assertions)]
2396 let mut matured_htlcs = Vec::new();
2398 // Produce actionable events from on-chain events having reached their threshold.
2399 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2401 OnchainEvent::HTLCUpdate { ref source, payment_hash, onchain_value_satoshis, input_idx } => {
2402 // Check for duplicate HTLC resolutions.
2403 #[cfg(debug_assertions)]
2406 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2407 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2408 call either transaction_unconfirmed for the conflicting transaction \
2409 or block_disconnected for a block containing it.");
2411 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2412 "A matured HTLC transaction conflicts with a maturing one; failed to \
2413 call either transaction_unconfirmed for the conflicting transaction \
2414 or block_disconnected for a block containing it.");
2415 matured_htlcs.push(source.clone());
2418 log_debug!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!(payment_hash.0));
2419 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2421 payment_preimage: None,
2422 source: source.clone(),
2423 onchain_value_satoshis,
2425 if let Some(idx) = input_idx {
2426 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC { input_idx: idx, payment_preimage: None });
2429 OnchainEvent::MaturingOutput { descriptor } => {
2430 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2431 self.pending_events.push(Event::SpendableOutputs {
2432 outputs: vec![descriptor]
2435 OnchainEvent::HTLCSpendConfirmation { input_idx, preimage, .. } => {
2436 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC { input_idx, payment_preimage: preimage });
2438 OnchainEvent::FundingSpendConfirmation { .. } => {
2439 self.funding_spend_confirmed = Some(entry.txid);
2444 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
2446 // Determine new outputs to watch by comparing against previously known outputs to watch,
2447 // updating the latter in the process.
2448 watch_outputs.retain(|&(ref txid, ref txouts)| {
2449 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2450 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2454 // If we see a transaction for which we registered outputs previously,
2455 // make sure the registered scriptpubkey at the expected index match
2456 // the actual transaction output one. We failed this case before #653.
2457 for tx in &txn_matched {
2458 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2459 for idx_and_script in outputs.iter() {
2460 assert!((idx_and_script.0 as usize) < tx.output.len());
2461 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2469 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2470 where B::Target: BroadcasterInterface,
2471 F::Target: FeeEstimator,
2474 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2477 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2478 //- maturing spendable output has transaction paying us has been disconnected
2479 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2481 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2483 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2486 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2493 B::Target: BroadcasterInterface,
2494 F::Target: FeeEstimator,
2497 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.txid != *txid);
2498 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2501 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2502 /// transactions thereof.
2503 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2504 let mut matched_txn = HashSet::new();
2505 txdata.iter().filter(|&&(_, tx)| {
2506 let mut matches = self.spends_watched_output(tx);
2507 for input in tx.input.iter() {
2508 if matches { break; }
2509 if matched_txn.contains(&input.previous_output.txid) {
2514 matched_txn.insert(tx.txid());
2517 }).map(|(_, tx)| *tx).collect()
2520 /// Checks if a given transaction spends any watched outputs.
2521 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2522 for input in tx.input.iter() {
2523 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2524 for (idx, _script_pubkey) in outputs.iter() {
2525 if *idx == input.previous_output.vout {
2528 // If the expected script is a known type, check that the witness
2529 // appears to be spending the correct type (ie that the match would
2530 // actually succeed in BIP 158/159-style filters).
2531 if _script_pubkey.is_v0_p2wsh() {
2532 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2533 } else if _script_pubkey.is_v0_p2wpkh() {
2534 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2535 } else { panic!(); }
2546 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
2547 // We need to consider all HTLCs which are:
2548 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2549 // transactions and we'd end up in a race, or
2550 // * are in our latest holder commitment transaction, as this is the thing we will
2551 // broadcast if we go on-chain.
2552 // Note that we consider HTLCs which were below dust threshold here - while they don't
2553 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2554 // to the source, and if we don't fail the channel we will have to ensure that the next
2555 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2556 // easier to just fail the channel as this case should be rare enough anyway.
2557 let height = self.best_block.height();
2558 macro_rules! scan_commitment {
2559 ($htlcs: expr, $holder_tx: expr) => {
2560 for ref htlc in $htlcs {
2561 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2562 // chain with enough room to claim the HTLC without our counterparty being able to
2563 // time out the HTLC first.
2564 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2565 // concern is being able to claim the corresponding inbound HTLC (on another
2566 // channel) before it expires. In fact, we don't even really care if our
2567 // counterparty here claims such an outbound HTLC after it expired as long as we
2568 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2569 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2570 // we give ourselves a few blocks of headroom after expiration before going
2571 // on-chain for an expired HTLC.
2572 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2573 // from us until we've reached the point where we go on-chain with the
2574 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2575 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2576 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2577 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2578 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2579 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2580 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2581 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2582 // The final, above, condition is checked for statically in channelmanager
2583 // with CHECK_CLTV_EXPIRY_SANITY_2.
2584 let htlc_outbound = $holder_tx == htlc.offered;
2585 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2586 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2587 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2594 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2596 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2597 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2598 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2601 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2602 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2603 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2610 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2611 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2612 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2613 'outer_loop: for input in &tx.input {
2614 let mut payment_data = None;
2615 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2616 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2617 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2618 let accepted_timeout_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && !revocation_sig_claim;
2619 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && !revocation_sig_claim;
2620 let offered_timeout_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::OfferedHTLC);
2622 let mut payment_preimage = PaymentPreimage([0; 32]);
2623 if accepted_preimage_claim {
2624 payment_preimage.0.copy_from_slice(&input.witness[3]);
2625 } else if offered_preimage_claim {
2626 payment_preimage.0.copy_from_slice(&input.witness[1]);
2629 macro_rules! log_claim {
2630 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2631 let outbound_htlc = $holder_tx == $htlc.offered;
2632 // HTLCs must either be claimed by a matching script type or through the
2634 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2635 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
2636 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2637 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
2638 // Further, only exactly one of the possible spend paths should have been
2639 // matched by any HTLC spend:
2640 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2641 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
2642 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
2643 revocation_sig_claim as u8, 1);
2644 if ($holder_tx && revocation_sig_claim) ||
2645 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2646 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2647 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2648 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2649 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2651 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2652 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2653 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2654 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2659 macro_rules! check_htlc_valid_counterparty {
2660 ($counterparty_txid: expr, $htlc_output: expr) => {
2661 if let Some(txid) = $counterparty_txid {
2662 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2663 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2664 if let &Some(ref source) = pending_source {
2665 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2666 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
2675 macro_rules! scan_commitment {
2676 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2677 for (ref htlc_output, source_option) in $htlcs {
2678 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2679 if let Some(ref source) = source_option {
2680 log_claim!($tx_info, $holder_tx, htlc_output, true);
2681 // We have a resolution of an HTLC either from one of our latest
2682 // holder commitment transactions or an unrevoked counterparty commitment
2683 // transaction. This implies we either learned a preimage, the HTLC
2684 // has timed out, or we screwed up. In any case, we should now
2685 // resolve the source HTLC with the original sender.
2686 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
2687 } else if !$holder_tx {
2688 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2689 if payment_data.is_none() {
2690 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2693 if payment_data.is_none() {
2694 log_claim!($tx_info, $holder_tx, htlc_output, false);
2695 let outbound_htlc = $holder_tx == htlc_output.offered;
2696 if !outbound_htlc || revocation_sig_claim {
2697 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2698 txid: tx.txid(), height,
2699 event: OnchainEvent::HTLCSpendConfirmation {
2700 input_idx: input.previous_output.vout,
2701 preimage: if accepted_preimage_claim || offered_preimage_claim {
2702 Some(payment_preimage) } else { None },
2703 // If this is a payment to us (!outbound_htlc, above),
2704 // wait for the CSV delay before dropping the HTLC from
2705 // claimable balance if the claim was an HTLC-Success
2707 on_to_local_output_csv: if accepted_preimage_claim {
2708 Some(self.on_holder_tx_csv) } else { None },
2712 // Outbound claims should always have payment_data, unless
2713 // we've already failed the HTLC as the commitment transaction
2714 // which was broadcasted was revoked. In that case, we should
2715 // spend the HTLC output here immediately, and expose that fact
2716 // as a Balance, something which we do not yet do.
2717 // TODO: Track the above as claimable!
2719 continue 'outer_loop;
2726 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2727 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2728 "our latest holder commitment tx", true);
2730 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2731 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2732 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2733 "our previous holder commitment tx", true);
2736 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2737 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2738 "counterparty commitment tx", false);
2741 // Check that scan_commitment, above, decided there is some source worth relaying an
2742 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2743 if let Some((source, payment_hash, amount_msat)) = payment_data {
2744 if accepted_preimage_claim {
2745 if !self.pending_monitor_events.iter().any(
2746 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2747 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2750 event: OnchainEvent::HTLCSpendConfirmation {
2751 input_idx: input.previous_output.vout,
2752 preimage: Some(payment_preimage),
2753 on_to_local_output_csv: None,
2756 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2758 payment_preimage: Some(payment_preimage),
2760 onchain_value_satoshis: Some(amount_msat / 1000),
2763 } else if offered_preimage_claim {
2764 if !self.pending_monitor_events.iter().any(
2765 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2766 upd.source == source
2768 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2771 event: OnchainEvent::HTLCSpendConfirmation {
2772 input_idx: input.previous_output.vout,
2773 preimage: Some(payment_preimage),
2774 on_to_local_output_csv: None,
2777 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2779 payment_preimage: Some(payment_preimage),
2781 onchain_value_satoshis: Some(amount_msat / 1000),
2785 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2786 if entry.height != height { return true; }
2788 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
2789 *htlc_source != source
2794 let entry = OnchainEventEntry {
2797 event: OnchainEvent::HTLCUpdate {
2798 source, payment_hash,
2799 onchain_value_satoshis: Some(amount_msat / 1000),
2800 input_idx: Some(input.previous_output.vout),
2803 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());
2804 self.onchain_events_awaiting_threshold_conf.push(entry);
2810 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2811 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2812 let mut spendable_output = None;
2813 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2814 if i > ::core::u16::MAX as usize {
2815 // While it is possible that an output exists on chain which is greater than the
2816 // 2^16th output in a given transaction, this is only possible if the output is not
2817 // in a lightning transaction and was instead placed there by some third party who
2818 // wishes to give us money for no reason.
2819 // Namely, any lightning transactions which we pre-sign will never have anywhere
2820 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2821 // scripts are not longer than one byte in length and because they are inherently
2822 // non-standard due to their size.
2823 // Thus, it is completely safe to ignore such outputs, and while it may result in
2824 // us ignoring non-lightning fund to us, that is only possible if someone fills
2825 // nearly a full block with garbage just to hit this case.
2828 if outp.script_pubkey == self.destination_script {
2829 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2830 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2831 output: outp.clone(),
2835 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2836 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2837 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2838 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2839 per_commitment_point: broadcasted_holder_revokable_script.1,
2840 to_self_delay: self.on_holder_tx_csv,
2841 output: outp.clone(),
2842 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2843 channel_keys_id: self.channel_keys_id,
2844 channel_value_satoshis: self.channel_value_satoshis,
2849 if self.counterparty_payment_script == outp.script_pubkey {
2850 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2851 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2852 output: outp.clone(),
2853 channel_keys_id: self.channel_keys_id,
2854 channel_value_satoshis: self.channel_value_satoshis,
2858 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
2859 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2860 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2861 output: outp.clone(),
2866 if let Some(spendable_output) = spendable_output {
2867 let entry = OnchainEventEntry {
2870 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
2872 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
2873 self.onchain_events_awaiting_threshold_conf.push(entry);
2878 /// `Persist` defines behavior for persisting channel monitors: this could mean
2879 /// writing once to disk, and/or uploading to one or more backup services.
2881 /// Note that for every new monitor, you **must** persist the new `ChannelMonitor`
2882 /// to disk/backups. And, on every update, you **must** persist either the
2883 /// `ChannelMonitorUpdate` or the updated monitor itself. Otherwise, there is risk
2884 /// of situations such as revoking a transaction, then crashing before this
2885 /// revocation can be persisted, then unintentionally broadcasting a revoked
2886 /// transaction and losing money. This is a risk because previous channel states
2887 /// are toxic, so it's important that whatever channel state is persisted is
2888 /// kept up-to-date.
2889 pub trait Persist<ChannelSigner: Sign> {
2890 /// Persist a new channel's data. The data can be stored any way you want, but
2891 /// the identifier provided by Rust-Lightning is the channel's outpoint (and
2892 /// it is up to you to maintain a correct mapping between the outpoint and the
2893 /// stored channel data). Note that you **must** persist every new monitor to
2894 /// disk. See the `Persist` trait documentation for more details.
2896 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2897 /// and [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2898 fn persist_new_channel(&self, id: OutPoint, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2900 /// Update one channel's data. The provided `ChannelMonitor` has already
2901 /// applied the given update.
2903 /// Note that on every update, you **must** persist either the
2904 /// `ChannelMonitorUpdate` or the updated monitor itself to disk/backups. See
2905 /// the `Persist` trait documentation for more details.
2907 /// If an implementer chooses to persist the updates only, they need to make
2908 /// sure that all the updates are applied to the `ChannelMonitors` *before*
2909 /// the set of channel monitors is given to the `ChannelManager`
2910 /// deserialization routine. See [`ChannelMonitor::update_monitor`] for
2911 /// applying a monitor update to a monitor. If full `ChannelMonitors` are
2912 /// persisted, then there is no need to persist individual updates.
2914 /// Note that there could be a performance tradeoff between persisting complete
2915 /// channel monitors on every update vs. persisting only updates and applying
2916 /// them in batches. The size of each monitor grows `O(number of state updates)`
2917 /// whereas updates are small and `O(1)`.
2919 /// See [`ChannelMonitor::write`] for writing out a `ChannelMonitor`,
2920 /// [`ChannelMonitorUpdate::write`] for writing out an update, and
2921 /// [`ChannelMonitorUpdateErr`] for requirements when returning errors.
2922 fn update_persisted_channel(&self, id: OutPoint, update: &ChannelMonitorUpdate, data: &ChannelMonitor<ChannelSigner>) -> Result<(), ChannelMonitorUpdateErr>;
2925 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2927 T::Target: BroadcasterInterface,
2928 F::Target: FeeEstimator,
2931 fn block_connected(&self, block: &Block, height: u32) {
2932 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2933 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2936 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2937 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2941 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
2943 T::Target: BroadcasterInterface,
2944 F::Target: FeeEstimator,
2947 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
2948 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
2951 fn transaction_unconfirmed(&self, txid: &Txid) {
2952 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
2955 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
2956 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
2959 fn get_relevant_txids(&self) -> Vec<Txid> {
2960 self.0.get_relevant_txids()
2964 const MAX_ALLOC_SIZE: usize = 64*1024;
2966 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2967 for (BlockHash, ChannelMonitor<Signer>) {
2968 fn read<R: io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2969 macro_rules! unwrap_obj {
2973 Err(_) => return Err(DecodeError::InvalidValue),
2978 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
2980 let latest_update_id: u64 = Readable::read(reader)?;
2981 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2983 let destination_script = Readable::read(reader)?;
2984 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2986 let revokable_address = Readable::read(reader)?;
2987 let per_commitment_point = Readable::read(reader)?;
2988 let revokable_script = Readable::read(reader)?;
2989 Some((revokable_address, per_commitment_point, revokable_script))
2992 _ => return Err(DecodeError::InvalidValue),
2994 let counterparty_payment_script = Readable::read(reader)?;
2995 let shutdown_script = {
2996 let script = <Script as Readable>::read(reader)?;
2997 if script.is_empty() { None } else { Some(script) }
3000 let channel_keys_id = Readable::read(reader)?;
3001 let holder_revocation_basepoint = Readable::read(reader)?;
3002 // Technically this can fail and serialize fail a round-trip, but only for serialization of
3003 // barely-init'd ChannelMonitors that we can't do anything with.
3004 let outpoint = OutPoint {
3005 txid: Readable::read(reader)?,
3006 index: Readable::read(reader)?,
3008 let funding_info = (outpoint, Readable::read(reader)?);
3009 let current_counterparty_commitment_txid = Readable::read(reader)?;
3010 let prev_counterparty_commitment_txid = Readable::read(reader)?;
3012 let counterparty_commitment_params = Readable::read(reader)?;
3013 let funding_redeemscript = Readable::read(reader)?;
3014 let channel_value_satoshis = Readable::read(reader)?;
3016 let their_cur_revocation_points = {
3017 let first_idx = <U48 as Readable>::read(reader)?.0;
3021 let first_point = Readable::read(reader)?;
3022 let second_point_slice: [u8; 33] = Readable::read(reader)?;
3023 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
3024 Some((first_idx, first_point, None))
3026 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
3031 let on_holder_tx_csv: u16 = Readable::read(reader)?;
3033 let commitment_secrets = Readable::read(reader)?;
3035 macro_rules! read_htlc_in_commitment {
3038 let offered: bool = Readable::read(reader)?;
3039 let amount_msat: u64 = Readable::read(reader)?;
3040 let cltv_expiry: u32 = Readable::read(reader)?;
3041 let payment_hash: PaymentHash = Readable::read(reader)?;
3042 let transaction_output_index: Option<u32> = Readable::read(reader)?;
3044 HTLCOutputInCommitment {
3045 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
3051 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
3052 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
3053 for _ in 0..counterparty_claimable_outpoints_len {
3054 let txid: Txid = Readable::read(reader)?;
3055 let htlcs_count: u64 = Readable::read(reader)?;
3056 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
3057 for _ in 0..htlcs_count {
3058 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
3060 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
3061 return Err(DecodeError::InvalidValue);
3065 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
3066 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
3067 for _ in 0..counterparty_commitment_txn_on_chain_len {
3068 let txid: Txid = Readable::read(reader)?;
3069 let commitment_number = <U48 as Readable>::read(reader)?.0;
3070 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
3071 return Err(DecodeError::InvalidValue);
3075 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3076 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3077 for _ in 0..counterparty_hash_commitment_number_len {
3078 let payment_hash: PaymentHash = Readable::read(reader)?;
3079 let commitment_number = <U48 as Readable>::read(reader)?.0;
3080 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3081 return Err(DecodeError::InvalidValue);
3085 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3086 match <u8 as Readable>::read(reader)? {
3089 Some(Readable::read(reader)?)
3091 _ => return Err(DecodeError::InvalidValue),
3093 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3095 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3096 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3098 let payment_preimages_len: u64 = Readable::read(reader)?;
3099 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3100 for _ in 0..payment_preimages_len {
3101 let preimage: PaymentPreimage = Readable::read(reader)?;
3102 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3103 if let Some(_) = payment_preimages.insert(hash, preimage) {
3104 return Err(DecodeError::InvalidValue);
3108 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3109 let mut pending_monitor_events = Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3)));
3110 for _ in 0..pending_monitor_events_len {
3111 let ev = match <u8 as Readable>::read(reader)? {
3112 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3113 1 => MonitorEvent::CommitmentTxBroadcasted(funding_info.0),
3114 _ => return Err(DecodeError::InvalidValue)
3116 pending_monitor_events.push(ev);
3119 let pending_events_len: u64 = Readable::read(reader)?;
3120 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3121 for _ in 0..pending_events_len {
3122 if let Some(event) = MaybeReadable::read(reader)? {
3123 pending_events.push(event);
3127 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
3129 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
3130 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
3131 for _ in 0..waiting_threshold_conf_len {
3132 if let Some(val) = MaybeReadable::read(reader)? {
3133 onchain_events_awaiting_threshold_conf.push(val);
3137 let outputs_to_watch_len: u64 = Readable::read(reader)?;
3138 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>>())));
3139 for _ in 0..outputs_to_watch_len {
3140 let txid = Readable::read(reader)?;
3141 let outputs_len: u64 = Readable::read(reader)?;
3142 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
3143 for _ in 0..outputs_len {
3144 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
3146 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
3147 return Err(DecodeError::InvalidValue);
3150 let onchain_tx_handler: OnchainTxHandler<Signer> = ReadableArgs::read(reader, keys_manager)?;
3152 let lockdown_from_offchain = Readable::read(reader)?;
3153 let holder_tx_signed = Readable::read(reader)?;
3155 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
3156 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
3157 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
3158 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
3159 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
3160 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
3161 return Err(DecodeError::InvalidValue);
3165 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
3166 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
3167 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
3168 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
3169 return Err(DecodeError::InvalidValue);
3172 let mut funding_spend_confirmed = None;
3173 let mut htlcs_resolved_on_chain = Some(Vec::new());
3174 read_tlv_fields!(reader, {
3175 (1, funding_spend_confirmed, option),
3176 (3, htlcs_resolved_on_chain, vec_type),
3179 let mut secp_ctx = Secp256k1::new();
3180 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
3182 Ok((best_block.block_hash(), ChannelMonitor {
3183 inner: Mutex::new(ChannelMonitorImpl {
3185 commitment_transaction_number_obscure_factor,
3188 broadcasted_holder_revokable_script,
3189 counterparty_payment_script,
3193 holder_revocation_basepoint,
3195 current_counterparty_commitment_txid,
3196 prev_counterparty_commitment_txid,
3198 counterparty_commitment_params,
3199 funding_redeemscript,
3200 channel_value_satoshis,
3201 their_cur_revocation_points,
3206 counterparty_claimable_outpoints,
3207 counterparty_commitment_txn_on_chain,
3208 counterparty_hash_commitment_number,
3210 prev_holder_signed_commitment_tx,
3211 current_holder_commitment_tx,
3212 current_counterparty_commitment_number,
3213 current_holder_commitment_number,
3216 pending_monitor_events,
3219 onchain_events_awaiting_threshold_conf,
3224 lockdown_from_offchain,
3226 funding_spend_confirmed,
3227 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
3239 use bitcoin::blockdata::script::{Script, Builder};
3240 use bitcoin::blockdata::opcodes;
3241 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
3242 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
3243 use bitcoin::util::bip143;
3244 use bitcoin::hashes::Hash;
3245 use bitcoin::hashes::sha256::Hash as Sha256;
3246 use bitcoin::hashes::hex::FromHex;
3247 use bitcoin::hash_types::Txid;
3248 use bitcoin::network::constants::Network;
3250 use chain::BestBlock;
3251 use chain::channelmonitor::ChannelMonitor;
3252 use chain::package::{WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC, WEIGHT_REVOKED_OUTPUT};
3253 use chain::transaction::OutPoint;
3254 use ln::{PaymentPreimage, PaymentHash};
3256 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
3257 use ln::script::ShutdownScript;
3258 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
3259 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
3260 use bitcoin::secp256k1::Secp256k1;
3261 use sync::{Arc, Mutex};
3262 use chain::keysinterface::InMemorySigner;
3266 fn test_prune_preimages() {
3267 let secp_ctx = Secp256k1::new();
3268 let logger = Arc::new(TestLogger::new());
3269 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
3270 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: Mutex::new(253) });
3272 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3273 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3275 let mut preimages = Vec::new();
3278 let preimage = PaymentPreimage([i; 32]);
3279 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3280 preimages.push((preimage, hash));
3284 macro_rules! preimages_slice_to_htlc_outputs {
3285 ($preimages_slice: expr) => {
3287 let mut res = Vec::new();
3288 for (idx, preimage) in $preimages_slice.iter().enumerate() {
3289 res.push((HTLCOutputInCommitment {
3293 payment_hash: preimage.1.clone(),
3294 transaction_output_index: Some(idx as u32),
3301 macro_rules! preimages_to_holder_htlcs {
3302 ($preimages_slice: expr) => {
3304 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
3305 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
3311 macro_rules! test_preimages_exist {
3312 ($preimages_slice: expr, $monitor: expr) => {
3313 for preimage in $preimages_slice {
3314 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
3319 let keys = InMemorySigner::new(
3321 SecretKey::from_slice(&[41; 32]).unwrap(),
3322 SecretKey::from_slice(&[41; 32]).unwrap(),
3323 SecretKey::from_slice(&[41; 32]).unwrap(),
3324 SecretKey::from_slice(&[41; 32]).unwrap(),
3325 SecretKey::from_slice(&[41; 32]).unwrap(),
3331 let counterparty_pubkeys = ChannelPublicKeys {
3332 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
3333 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
3334 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
3335 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
3336 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
3338 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
3339 let channel_parameters = ChannelTransactionParameters {
3340 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
3341 holder_selected_contest_delay: 66,
3342 is_outbound_from_holder: true,
3343 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
3344 pubkeys: counterparty_pubkeys,
3345 selected_contest_delay: 67,
3347 funding_outpoint: Some(funding_outpoint),
3349 // Prune with one old state and a holder commitment tx holding a few overlaps with the
3351 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3352 let best_block = BestBlock::from_genesis(Network::Testnet);
3353 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
3354 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
3355 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
3356 &channel_parameters,
3357 Script::new(), 46, 0,
3358 HolderCommitmentTransaction::dummy(), best_block);
3360 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
3361 let dummy_txid = dummy_tx.txid();
3362 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
3363 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
3364 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
3365 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
3366 for &(ref preimage, ref hash) in preimages.iter() {
3367 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
3370 // Now provide a secret, pruning preimages 10-15
3371 let mut secret = [0; 32];
3372 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
3373 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
3374 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
3375 test_preimages_exist!(&preimages[0..10], monitor);
3376 test_preimages_exist!(&preimages[15..20], monitor);
3378 // Now provide a further secret, pruning preimages 15-17
3379 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
3380 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
3381 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
3382 test_preimages_exist!(&preimages[0..10], monitor);
3383 test_preimages_exist!(&preimages[17..20], monitor);
3385 // Now update holder commitment tx info, pruning only element 18 as we still care about the
3386 // previous commitment tx's preimages too
3387 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
3388 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
3389 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
3390 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
3391 test_preimages_exist!(&preimages[0..10], monitor);
3392 test_preimages_exist!(&preimages[18..20], monitor);
3394 // But if we do it again, we'll prune 5-10
3395 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
3396 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
3397 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
3398 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
3399 test_preimages_exist!(&preimages[0..5], monitor);
3403 fn test_claim_txn_weight_computation() {
3404 // We test Claim txn weight, knowing that we want expected weigth and
3405 // not actual case to avoid sigs and time-lock delays hell variances.
3407 let secp_ctx = Secp256k1::new();
3408 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
3409 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
3410 let mut sum_actual_sigs = 0;
3412 macro_rules! sign_input {
3413 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr) => {
3414 let htlc = HTLCOutputInCommitment {
3415 offered: if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_OFFERED_HTLC { true } else { false },
3417 cltv_expiry: 2 << 16,
3418 payment_hash: PaymentHash([1; 32]),
3419 transaction_output_index: Some($idx as u32),
3421 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
3422 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
3423 let sig = secp_ctx.sign(&sighash, &privkey);
3424 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
3425 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
3426 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
3427 if *$weight == WEIGHT_REVOKED_OUTPUT {
3428 $sighash_parts.access_witness($idx).push(vec!(1));
3429 } else if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_REVOKED_RECEIVED_HTLC {
3430 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
3431 } else if *$weight == WEIGHT_RECEIVED_HTLC {
3432 $sighash_parts.access_witness($idx).push(vec![0]);
3434 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
3436 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
3437 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
3438 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
3439 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
3443 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3444 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3446 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3447 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3449 claim_tx.input.push(TxIn {
3450 previous_output: BitcoinOutPoint {
3454 script_sig: Script::new(),
3455 sequence: 0xfffffffd,
3456 witness: Vec::new(),
3459 claim_tx.output.push(TxOut {
3460 script_pubkey: script_pubkey.clone(),
3463 let base_weight = claim_tx.get_weight();
3464 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC];
3465 let mut inputs_total_weight = 2; // count segwit flags
3467 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3468 for (idx, inp) in inputs_weight.iter().enumerate() {
3469 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3470 inputs_total_weight += inp;
3473 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3475 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3476 claim_tx.input.clear();
3477 sum_actual_sigs = 0;
3479 claim_tx.input.push(TxIn {
3480 previous_output: BitcoinOutPoint {
3484 script_sig: Script::new(),
3485 sequence: 0xfffffffd,
3486 witness: Vec::new(),
3489 let base_weight = claim_tx.get_weight();
3490 let inputs_weight = vec![WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC];
3491 let mut inputs_total_weight = 2; // count segwit flags
3493 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3494 for (idx, inp) in inputs_weight.iter().enumerate() {
3495 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3496 inputs_total_weight += inp;
3499 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3501 // Justice tx with 1 revoked HTLC-Success tx output
3502 claim_tx.input.clear();
3503 sum_actual_sigs = 0;
3504 claim_tx.input.push(TxIn {
3505 previous_output: BitcoinOutPoint {
3509 script_sig: Script::new(),
3510 sequence: 0xfffffffd,
3511 witness: Vec::new(),
3513 let base_weight = claim_tx.get_weight();
3514 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
3515 let mut inputs_total_weight = 2; // count segwit flags
3517 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3518 for (idx, inp) in inputs_weight.iter().enumerate() {
3519 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3520 inputs_total_weight += inp;
3523 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
3526 // Further testing is done in the ChannelManager integration tests.