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 latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date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 /// General Err type for ChannelMonitor actions. Generally, this implies that the data provided is
119 /// inconsistent with the ChannelMonitor being called. eg for ChannelMonitor::update_monitor this
120 /// means you tried to update a monitor for a different channel or the ChannelMonitorUpdate was
122 /// Contains a developer-readable error message.
123 #[derive(Clone, Debug)]
124 pub struct MonitorUpdateError(pub &'static str);
126 /// An event to be processed by the ChannelManager.
127 #[derive(Clone, PartialEq)]
128 pub enum MonitorEvent {
129 /// A monitor event containing an HTLCUpdate.
130 HTLCEvent(HTLCUpdate),
132 /// A monitor event that the Channel's commitment transaction was confirmed.
133 CommitmentTxConfirmed(OutPoint),
135 /// Indicates a [`ChannelMonitor`] update has completed. See
136 /// [`ChannelMonitorUpdateErr::TemporaryFailure`] for more information on how this is used.
138 /// [`ChannelMonitorUpdateErr::TemporaryFailure`]: super::ChannelMonitorUpdateErr::TemporaryFailure
140 /// The funding outpoint of the [`ChannelMonitor`] that was updated
141 funding_txo: OutPoint,
142 /// The Update ID from [`ChannelMonitorUpdate::update_id`] which was applied or
143 /// [`ChannelMonitor::get_latest_update_id`].
145 /// Note that this should only be set to a given update's ID if all previous updates for the
146 /// same [`ChannelMonitor`] have been applied and persisted.
147 monitor_update_id: u64,
150 impl_writeable_tlv_based_enum_upgradable!(MonitorEvent,
151 // Note that UpdateCompleted is currently never serialized to disk as it is generated only in ChainMonitor
152 (0, UpdateCompleted) => {
153 (0, funding_txo, required),
154 (2, monitor_update_id, required),
158 (4, CommitmentTxConfirmed),
161 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
162 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
163 /// preimage claim backward will lead to loss of funds.
164 #[derive(Clone, PartialEq)]
165 pub struct HTLCUpdate {
166 pub(crate) payment_hash: PaymentHash,
167 pub(crate) payment_preimage: Option<PaymentPreimage>,
168 pub(crate) source: HTLCSource,
169 pub(crate) onchain_value_satoshis: Option<u64>,
171 impl_writeable_tlv_based!(HTLCUpdate, {
172 (0, payment_hash, required),
173 (1, onchain_value_satoshis, option),
174 (2, source, required),
175 (4, payment_preimage, option),
178 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
179 /// instead claiming it in its own individual transaction.
180 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
181 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
182 /// HTLC-Success transaction.
183 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
184 /// transaction confirmed (and we use it in a few more, equivalent, places).
185 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
186 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
187 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
188 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
189 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
190 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
191 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
192 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
193 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
194 /// accurate block height.
195 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
196 /// with at worst this delay, so we are not only using this value as a mercy for them but also
197 /// us as a safeguard to delay with enough time.
198 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
199 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
200 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
203 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
204 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
205 /// by a [`ChannelMonitor`] may be incorrect.
206 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
207 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
208 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
209 // keep bumping another claim tx to solve the outpoint.
210 pub const ANTI_REORG_DELAY: u32 = 6;
211 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
212 /// refuse to accept a new HTLC.
214 /// This is used for a few separate purposes:
215 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
216 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
218 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
219 /// condition with the above), we will fail this HTLC without telling the user we received it,
220 /// 3) if we are waiting on a connection or a channel state update to send an HTLC to a peer, and
221 /// that HTLC expires within this many blocks, we will simply fail the HTLC instead.
223 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
224 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
226 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
227 /// in a race condition between the user connecting a block (which would fail it) and the user
228 /// providing us the preimage (which would claim it).
230 /// (3) is about our counterparty - we don't want to relay an HTLC to a counterparty when they may
231 /// end up force-closing the channel on us to claim it.
232 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
234 // TODO(devrandom) replace this with HolderCommitmentTransaction
235 #[derive(Clone, PartialEq)]
236 struct HolderSignedTx {
237 /// txid of the transaction in tx, just used to make comparison faster
239 revocation_key: PublicKey,
240 a_htlc_key: PublicKey,
241 b_htlc_key: PublicKey,
242 delayed_payment_key: PublicKey,
243 per_commitment_point: PublicKey,
244 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
245 to_self_value_sat: u64,
248 impl_writeable_tlv_based!(HolderSignedTx, {
250 // Note that this is filled in with data from OnchainTxHandler if it's missing.
251 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
252 (1, to_self_value_sat, (default_value, u64::max_value())),
253 (2, revocation_key, required),
254 (4, a_htlc_key, required),
255 (6, b_htlc_key, required),
256 (8, delayed_payment_key, required),
257 (10, per_commitment_point, required),
258 (12, feerate_per_kw, required),
259 (14, htlc_outputs, vec_type)
262 /// We use this to track static counterparty commitment transaction data and to generate any
263 /// justice or 2nd-stage preimage/timeout transactions.
265 struct CounterpartyCommitmentParameters {
266 counterparty_delayed_payment_base_key: PublicKey,
267 counterparty_htlc_base_key: PublicKey,
268 on_counterparty_tx_csv: u16,
271 impl Writeable for CounterpartyCommitmentParameters {
272 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
273 w.write_all(&byte_utils::be64_to_array(0))?;
274 write_tlv_fields!(w, {
275 (0, self.counterparty_delayed_payment_base_key, required),
276 (2, self.counterparty_htlc_base_key, required),
277 (4, self.on_counterparty_tx_csv, required),
282 impl Readable for CounterpartyCommitmentParameters {
283 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
284 let counterparty_commitment_transaction = {
285 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
286 // used. Read it for compatibility.
287 let per_htlc_len: u64 = Readable::read(r)?;
288 for _ in 0..per_htlc_len {
289 let _txid: Txid = Readable::read(r)?;
290 let htlcs_count: u64 = Readable::read(r)?;
291 for _ in 0..htlcs_count {
292 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
296 let mut counterparty_delayed_payment_base_key = OptionDeserWrapper(None);
297 let mut counterparty_htlc_base_key = OptionDeserWrapper(None);
298 let mut on_counterparty_tx_csv: u16 = 0;
299 read_tlv_fields!(r, {
300 (0, counterparty_delayed_payment_base_key, required),
301 (2, counterparty_htlc_base_key, required),
302 (4, on_counterparty_tx_csv, required),
304 CounterpartyCommitmentParameters {
305 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
306 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
307 on_counterparty_tx_csv,
310 Ok(counterparty_commitment_transaction)
314 /// An entry for an [`OnchainEvent`], stating the block height when the event was observed and the
315 /// transaction causing it.
317 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
319 struct OnchainEventEntry {
325 impl OnchainEventEntry {
326 fn confirmation_threshold(&self) -> u32 {
327 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
329 OnchainEvent::MaturingOutput {
330 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
332 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
333 // it's broadcastable when we see the previous block.
334 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
336 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
337 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
338 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
339 // it's broadcastable when we see the previous block.
340 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
347 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
348 best_block.height() >= self.confirmation_threshold()
352 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
353 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
356 /// An outbound HTLC failing after a transaction is confirmed. Used
357 /// * when an outbound HTLC output is spent by us after the HTLC timed out
358 /// * an outbound HTLC which was not present in the commitment transaction which appeared
359 /// on-chain (either because it was not fully committed to or it was dust).
360 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
361 /// appearing only as an `HTLCSpendConfirmation`, below.
364 payment_hash: PaymentHash,
365 onchain_value_satoshis: Option<u64>,
366 /// None in the second case, above, ie when there is no relevant output in the commitment
367 /// transaction which appeared on chain.
368 input_idx: Option<u32>,
371 descriptor: SpendableOutputDescriptor,
373 /// A spend of the funding output, either a commitment transaction or a cooperative closing
375 FundingSpendConfirmation {
376 /// The CSV delay for the output of the funding spend transaction (implying it is a local
377 /// commitment transaction, and this is the delay on the to_self output).
378 on_local_output_csv: Option<u16>,
380 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
381 /// is constructed. This is used when
382 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
383 /// immediately claim the HTLC on the inbound edge and track the resolution here,
384 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
385 /// * an inbound HTLC is claimed by us (with a preimage).
386 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
388 HTLCSpendConfirmation {
390 /// If the claim was made by either party with a preimage, this is filled in
391 preimage: Option<PaymentPreimage>,
392 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
393 /// we set this to the output CSV value which we will have to wait until to spend the
394 /// output (and generate a SpendableOutput event).
395 on_to_local_output_csv: Option<u16>,
399 impl Writeable for OnchainEventEntry {
400 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
401 write_tlv_fields!(writer, {
402 (0, self.txid, required),
403 (2, self.height, required),
404 (4, self.event, required),
410 impl MaybeReadable for OnchainEventEntry {
411 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
412 let mut txid = Default::default();
414 let mut event = None;
415 read_tlv_fields!(reader, {
417 (2, height, required),
418 (4, event, ignorable),
420 if let Some(ev) = event {
421 Ok(Some(Self { txid, height, event: ev }))
428 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
430 (0, source, required),
431 (1, onchain_value_satoshis, option),
432 (2, payment_hash, required),
433 (3, input_idx, option),
435 (1, MaturingOutput) => {
436 (0, descriptor, required),
438 (3, FundingSpendConfirmation) => {
439 (0, on_local_output_csv, option),
441 (5, HTLCSpendConfirmation) => {
442 (0, input_idx, required),
443 (2, preimage, option),
444 (4, on_to_local_output_csv, option),
449 #[cfg_attr(any(test, feature = "fuzztarget", feature = "_test_utils"), derive(PartialEq))]
451 pub(crate) enum ChannelMonitorUpdateStep {
452 LatestHolderCommitmentTXInfo {
453 commitment_tx: HolderCommitmentTransaction,
454 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
456 LatestCounterpartyCommitmentTXInfo {
457 commitment_txid: Txid,
458 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
459 commitment_number: u64,
460 their_revocation_point: PublicKey,
463 payment_preimage: PaymentPreimage,
469 /// Used to indicate that the no future updates will occur, and likely that the latest holder
470 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
472 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
473 /// think we've fallen behind!
474 should_broadcast: bool,
477 scriptpubkey: Script,
481 impl_writeable_tlv_based_enum_upgradable!(ChannelMonitorUpdateStep,
482 (0, LatestHolderCommitmentTXInfo) => {
483 (0, commitment_tx, required),
484 (2, htlc_outputs, vec_type),
486 (1, LatestCounterpartyCommitmentTXInfo) => {
487 (0, commitment_txid, required),
488 (2, commitment_number, required),
489 (4, their_revocation_point, required),
490 (6, htlc_outputs, vec_type),
492 (2, PaymentPreimage) => {
493 (0, payment_preimage, required),
495 (3, CommitmentSecret) => {
497 (2, secret, required),
499 (4, ChannelForceClosed) => {
500 (0, should_broadcast, required),
502 (5, ShutdownScript) => {
503 (0, scriptpubkey, required),
507 /// Details about the balance(s) available for spending once the channel appears on chain.
509 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
511 #[derive(Clone, Debug, PartialEq, Eq)]
512 #[cfg_attr(test, derive(PartialOrd, Ord))]
514 /// The channel is not yet closed (or the commitment or closing transaction has not yet
515 /// appeared in a block). The given balance is claimable (less on-chain fees) if the channel is
516 /// force-closed now.
517 ClaimableOnChannelClose {
518 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
519 /// required to do so.
520 claimable_amount_satoshis: u64,
522 /// The channel has been closed, and the given balance is ours but awaiting confirmations until
523 /// we consider it spendable.
524 ClaimableAwaitingConfirmations {
525 /// The amount available to claim, in satoshis, possibly excluding the on-chain fees which
526 /// were spent in broadcasting the transaction.
527 claimable_amount_satoshis: u64,
528 /// The height at which an [`Event::SpendableOutputs`] event will be generated for this
530 confirmation_height: u32,
532 /// The channel has been closed, and the given balance should be ours but awaiting spending
533 /// transaction confirmation. If the spending transaction does not confirm in time, it is
534 /// possible our counterparty can take the funds by broadcasting an HTLC timeout on-chain.
536 /// Once the spending transaction confirms, before it has reached enough confirmations to be
537 /// considered safe from chain reorganizations, the balance will instead be provided via
538 /// [`Balance::ClaimableAwaitingConfirmations`].
539 ContentiousClaimable {
540 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
541 /// required to do so.
542 claimable_amount_satoshis: u64,
543 /// The height at which the counterparty may be able to claim the balance if we have not
547 /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
548 /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
549 /// likely to be claimed by our counterparty before we do.
550 MaybeClaimableHTLCAwaitingTimeout {
551 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
552 /// required to do so.
553 claimable_amount_satoshis: u64,
554 /// The height at which we will be able to claim the balance if our counterparty has not
556 claimable_height: u32,
560 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
562 struct IrrevocablyResolvedHTLC {
564 /// Only set if the HTLC claim was ours using a payment preimage
565 payment_preimage: Option<PaymentPreimage>,
568 impl_writeable_tlv_based!(IrrevocablyResolvedHTLC, {
569 (0, input_idx, required),
570 (2, payment_preimage, option),
573 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
574 /// on-chain transactions to ensure no loss of funds occurs.
576 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
577 /// information and are actively monitoring the chain.
579 /// Pending Events or updated HTLCs which have not yet been read out by
580 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
581 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
582 /// gotten are fully handled before re-serializing the new state.
584 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
585 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
586 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
587 /// returned block hash and the the current chain and then reconnecting blocks to get to the
588 /// best chain) upon deserializing the object!
589 pub struct ChannelMonitor<Signer: Sign> {
591 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
593 inner: Mutex<ChannelMonitorImpl<Signer>>,
596 pub(crate) struct ChannelMonitorImpl<Signer: Sign> {
597 latest_update_id: u64,
598 commitment_transaction_number_obscure_factor: u64,
600 destination_script: Script,
601 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
602 counterparty_payment_script: Script,
603 shutdown_script: Option<Script>,
605 channel_keys_id: [u8; 32],
606 holder_revocation_basepoint: PublicKey,
607 funding_info: (OutPoint, Script),
608 current_counterparty_commitment_txid: Option<Txid>,
609 prev_counterparty_commitment_txid: Option<Txid>,
611 counterparty_commitment_params: CounterpartyCommitmentParameters,
612 funding_redeemscript: Script,
613 channel_value_satoshis: u64,
614 // first is the idx of the first of the two revocation points
615 their_cur_revocation_points: Option<(u64, PublicKey, Option<PublicKey>)>,
617 on_holder_tx_csv: u16,
619 commitment_secrets: CounterpartyCommitmentSecrets,
620 /// The set of outpoints in each counterparty commitment transaction. We always need at least
621 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
622 /// transaction broadcast as we need to be able to construct the witness script in all cases.
623 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
624 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
625 /// Nor can we figure out their commitment numbers without the commitment transaction they are
626 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
627 /// commitment transactions which we find on-chain, mapping them to the commitment number which
628 /// can be used to derive the revocation key and claim the transactions.
629 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
630 /// Cache used to make pruning of payment_preimages faster.
631 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
632 /// counterparty transactions (ie should remain pretty small).
633 /// Serialized to disk but should generally not be sent to Watchtowers.
634 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
636 // We store two holder commitment transactions to avoid any race conditions where we may update
637 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
638 // various monitors for one channel being out of sync, and us broadcasting a holder
639 // transaction for which we have deleted claim information on some watchtowers.
640 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
641 current_holder_commitment_tx: HolderSignedTx,
643 // Used just for ChannelManager to make sure it has the latest channel data during
645 current_counterparty_commitment_number: u64,
646 // Used just for ChannelManager to make sure it has the latest channel data during
648 current_holder_commitment_number: u64,
650 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
652 pending_monitor_events: Vec<MonitorEvent>,
653 pending_events: Vec<Event>,
655 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
656 // which to take actions once they reach enough confirmations. Each entry includes the
657 // transaction's id and the height when the transaction was confirmed on chain.
658 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
660 // If we get serialized out and re-read, we need to make sure that the chain monitoring
661 // interface knows about the TXOs that we want to be notified of spends of. We could probably
662 // be smart and derive them from the above storage fields, but its much simpler and more
663 // Obviously Correct (tm) if we just keep track of them explicitly.
664 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
667 pub onchain_tx_handler: OnchainTxHandler<Signer>,
669 onchain_tx_handler: OnchainTxHandler<Signer>,
671 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
672 // channel has been force-closed. After this is set, no further holder commitment transaction
673 // updates may occur, and we panic!() if one is provided.
674 lockdown_from_offchain: bool,
676 // Set once we've signed a holder commitment transaction and handed it over to our
677 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
678 // may occur, and we fail any such monitor updates.
680 // In case of update rejection due to a locally already signed commitment transaction, we
681 // nevertheless store update content to track in case of concurrent broadcast by another
682 // remote monitor out-of-order with regards to the block view.
683 holder_tx_signed: bool,
685 funding_spend_confirmed: Option<Txid>,
686 /// The set of HTLCs which have been either claimed or failed on chain and have reached
687 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
688 /// spending CSV for revocable outputs).
689 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
691 // We simply modify best_block in Channel's block_connected so that serialization is
692 // consistent but hopefully the users' copy handles block_connected in a consistent way.
693 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
694 // their best_block from its state and not based on updated copies that didn't run through
695 // the full block_connected).
696 best_block: BestBlock,
698 secp_ctx: Secp256k1<secp256k1::All>, //TODO: dedup this a bit...
701 /// Transaction outputs to watch for on-chain spends.
702 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
704 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
705 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
706 /// underlying object
707 impl<Signer: Sign> PartialEq for ChannelMonitor<Signer> {
708 fn eq(&self, other: &Self) -> bool {
709 let inner = self.inner.lock().unwrap();
710 let other = other.inner.lock().unwrap();
715 #[cfg(any(test, feature = "fuzztarget", feature = "_test_utils"))]
716 /// Used only in testing and fuzztarget to check serialization roundtrips don't change the
717 /// underlying object
718 impl<Signer: Sign> PartialEq for ChannelMonitorImpl<Signer> {
719 fn eq(&self, other: &Self) -> bool {
720 if self.latest_update_id != other.latest_update_id ||
721 self.commitment_transaction_number_obscure_factor != other.commitment_transaction_number_obscure_factor ||
722 self.destination_script != other.destination_script ||
723 self.broadcasted_holder_revokable_script != other.broadcasted_holder_revokable_script ||
724 self.counterparty_payment_script != other.counterparty_payment_script ||
725 self.channel_keys_id != other.channel_keys_id ||
726 self.holder_revocation_basepoint != other.holder_revocation_basepoint ||
727 self.funding_info != other.funding_info ||
728 self.current_counterparty_commitment_txid != other.current_counterparty_commitment_txid ||
729 self.prev_counterparty_commitment_txid != other.prev_counterparty_commitment_txid ||
730 self.counterparty_commitment_params != other.counterparty_commitment_params ||
731 self.funding_redeemscript != other.funding_redeemscript ||
732 self.channel_value_satoshis != other.channel_value_satoshis ||
733 self.their_cur_revocation_points != other.their_cur_revocation_points ||
734 self.on_holder_tx_csv != other.on_holder_tx_csv ||
735 self.commitment_secrets != other.commitment_secrets ||
736 self.counterparty_claimable_outpoints != other.counterparty_claimable_outpoints ||
737 self.counterparty_commitment_txn_on_chain != other.counterparty_commitment_txn_on_chain ||
738 self.counterparty_hash_commitment_number != other.counterparty_hash_commitment_number ||
739 self.prev_holder_signed_commitment_tx != other.prev_holder_signed_commitment_tx ||
740 self.current_counterparty_commitment_number != other.current_counterparty_commitment_number ||
741 self.current_holder_commitment_number != other.current_holder_commitment_number ||
742 self.current_holder_commitment_tx != other.current_holder_commitment_tx ||
743 self.payment_preimages != other.payment_preimages ||
744 self.pending_monitor_events != other.pending_monitor_events ||
745 self.pending_events.len() != other.pending_events.len() || // We trust events to round-trip properly
746 self.onchain_events_awaiting_threshold_conf != other.onchain_events_awaiting_threshold_conf ||
747 self.outputs_to_watch != other.outputs_to_watch ||
748 self.lockdown_from_offchain != other.lockdown_from_offchain ||
749 self.holder_tx_signed != other.holder_tx_signed ||
750 self.funding_spend_confirmed != other.funding_spend_confirmed ||
751 self.htlcs_resolved_on_chain != other.htlcs_resolved_on_chain
760 impl<Signer: Sign> Writeable for ChannelMonitor<Signer> {
761 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
762 self.inner.lock().unwrap().write(writer)
766 // These are also used for ChannelMonitorUpdate, above.
767 const SERIALIZATION_VERSION: u8 = 1;
768 const MIN_SERIALIZATION_VERSION: u8 = 1;
770 impl<Signer: Sign> Writeable for ChannelMonitorImpl<Signer> {
771 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
772 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
774 self.latest_update_id.write(writer)?;
776 // Set in initial Channel-object creation, so should always be set by now:
777 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
779 self.destination_script.write(writer)?;
780 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
781 writer.write_all(&[0; 1])?;
782 broadcasted_holder_revokable_script.0.write(writer)?;
783 broadcasted_holder_revokable_script.1.write(writer)?;
784 broadcasted_holder_revokable_script.2.write(writer)?;
786 writer.write_all(&[1; 1])?;
789 self.counterparty_payment_script.write(writer)?;
790 match &self.shutdown_script {
791 Some(script) => script.write(writer)?,
792 None => Script::new().write(writer)?,
795 self.channel_keys_id.write(writer)?;
796 self.holder_revocation_basepoint.write(writer)?;
797 writer.write_all(&self.funding_info.0.txid[..])?;
798 writer.write_all(&byte_utils::be16_to_array(self.funding_info.0.index))?;
799 self.funding_info.1.write(writer)?;
800 self.current_counterparty_commitment_txid.write(writer)?;
801 self.prev_counterparty_commitment_txid.write(writer)?;
803 self.counterparty_commitment_params.write(writer)?;
804 self.funding_redeemscript.write(writer)?;
805 self.channel_value_satoshis.write(writer)?;
807 match self.their_cur_revocation_points {
808 Some((idx, pubkey, second_option)) => {
809 writer.write_all(&byte_utils::be48_to_array(idx))?;
810 writer.write_all(&pubkey.serialize())?;
811 match second_option {
812 Some(second_pubkey) => {
813 writer.write_all(&second_pubkey.serialize())?;
816 writer.write_all(&[0; 33])?;
821 writer.write_all(&byte_utils::be48_to_array(0))?;
825 writer.write_all(&byte_utils::be16_to_array(self.on_holder_tx_csv))?;
827 self.commitment_secrets.write(writer)?;
829 macro_rules! serialize_htlc_in_commitment {
830 ($htlc_output: expr) => {
831 writer.write_all(&[$htlc_output.offered as u8; 1])?;
832 writer.write_all(&byte_utils::be64_to_array($htlc_output.amount_msat))?;
833 writer.write_all(&byte_utils::be32_to_array($htlc_output.cltv_expiry))?;
834 writer.write_all(&$htlc_output.payment_hash.0[..])?;
835 $htlc_output.transaction_output_index.write(writer)?;
839 writer.write_all(&byte_utils::be64_to_array(self.counterparty_claimable_outpoints.len() as u64))?;
840 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
841 writer.write_all(&txid[..])?;
842 writer.write_all(&byte_utils::be64_to_array(htlc_infos.len() as u64))?;
843 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
844 serialize_htlc_in_commitment!(htlc_output);
845 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
849 writer.write_all(&byte_utils::be64_to_array(self.counterparty_commitment_txn_on_chain.len() as u64))?;
850 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
851 writer.write_all(&txid[..])?;
852 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
855 writer.write_all(&byte_utils::be64_to_array(self.counterparty_hash_commitment_number.len() as u64))?;
856 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
857 writer.write_all(&payment_hash.0[..])?;
858 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
861 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
862 writer.write_all(&[1; 1])?;
863 prev_holder_tx.write(writer)?;
865 writer.write_all(&[0; 1])?;
868 self.current_holder_commitment_tx.write(writer)?;
870 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
871 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
873 writer.write_all(&byte_utils::be64_to_array(self.payment_preimages.len() as u64))?;
874 for payment_preimage in self.payment_preimages.values() {
875 writer.write_all(&payment_preimage.0[..])?;
878 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
879 MonitorEvent::HTLCEvent(_) => true,
880 MonitorEvent::CommitmentTxConfirmed(_) => true,
882 }).count() as u64).to_be_bytes())?;
883 for event in self.pending_monitor_events.iter() {
885 MonitorEvent::HTLCEvent(upd) => {
889 MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)?,
890 _ => {}, // Covered in the TLV writes below
894 writer.write_all(&byte_utils::be64_to_array(self.pending_events.len() as u64))?;
895 for event in self.pending_events.iter() {
896 event.write(writer)?;
899 self.best_block.block_hash().write(writer)?;
900 writer.write_all(&byte_utils::be32_to_array(self.best_block.height()))?;
902 writer.write_all(&byte_utils::be64_to_array(self.onchain_events_awaiting_threshold_conf.len() as u64))?;
903 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
904 entry.write(writer)?;
907 (self.outputs_to_watch.len() as u64).write(writer)?;
908 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
910 (idx_scripts.len() as u64).write(writer)?;
911 for (idx, script) in idx_scripts.iter() {
913 script.write(writer)?;
916 self.onchain_tx_handler.write(writer)?;
918 self.lockdown_from_offchain.write(writer)?;
919 self.holder_tx_signed.write(writer)?;
921 write_tlv_fields!(writer, {
922 (1, self.funding_spend_confirmed, option),
923 (3, self.htlcs_resolved_on_chain, vec_type),
924 (5, self.pending_monitor_events, vec_type),
931 impl<Signer: Sign> ChannelMonitor<Signer> {
932 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
933 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
934 channel_parameters: &ChannelTransactionParameters,
935 funding_redeemscript: Script, channel_value_satoshis: u64,
936 commitment_transaction_number_obscure_factor: u64,
937 initial_holder_commitment_tx: HolderCommitmentTransaction,
938 best_block: BestBlock) -> ChannelMonitor<Signer> {
940 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
941 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
942 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
944 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
945 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
946 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
947 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
949 let channel_keys_id = keys.channel_keys_id();
950 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
952 // block for Rust 1.34 compat
953 let (holder_commitment_tx, current_holder_commitment_number) = {
954 let trusted_tx = initial_holder_commitment_tx.trust();
955 let txid = trusted_tx.txid();
957 let tx_keys = trusted_tx.keys();
958 let holder_commitment_tx = HolderSignedTx {
960 revocation_key: tx_keys.revocation_key,
961 a_htlc_key: tx_keys.broadcaster_htlc_key,
962 b_htlc_key: tx_keys.countersignatory_htlc_key,
963 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
964 per_commitment_point: tx_keys.per_commitment_point,
965 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
966 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
967 feerate_per_kw: trusted_tx.feerate_per_kw(),
969 (holder_commitment_tx, trusted_tx.commitment_number())
972 let onchain_tx_handler =
973 OnchainTxHandler::new(destination_script.clone(), keys,
974 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx.clone());
976 let mut outputs_to_watch = HashMap::new();
977 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
980 inner: Mutex::new(ChannelMonitorImpl {
982 commitment_transaction_number_obscure_factor,
984 destination_script: destination_script.clone(),
985 broadcasted_holder_revokable_script: None,
986 counterparty_payment_script,
990 holder_revocation_basepoint,
992 current_counterparty_commitment_txid: None,
993 prev_counterparty_commitment_txid: None,
995 counterparty_commitment_params,
996 funding_redeemscript,
997 channel_value_satoshis,
998 their_cur_revocation_points: None,
1000 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1002 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1003 counterparty_claimable_outpoints: HashMap::new(),
1004 counterparty_commitment_txn_on_chain: HashMap::new(),
1005 counterparty_hash_commitment_number: HashMap::new(),
1007 prev_holder_signed_commitment_tx: None,
1008 current_holder_commitment_tx: holder_commitment_tx,
1009 current_counterparty_commitment_number: 1 << 48,
1010 current_holder_commitment_number,
1012 payment_preimages: HashMap::new(),
1013 pending_monitor_events: Vec::new(),
1014 pending_events: Vec::new(),
1016 onchain_events_awaiting_threshold_conf: Vec::new(),
1021 lockdown_from_offchain: false,
1022 holder_tx_signed: false,
1023 funding_spend_confirmed: None,
1024 htlcs_resolved_on_chain: Vec::new(),
1034 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1035 self.inner.lock().unwrap().provide_secret(idx, secret)
1038 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1039 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1040 /// possibly future revocation/preimage information) to claim outputs where possible.
1041 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1042 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1045 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1046 commitment_number: u64,
1047 their_revocation_point: PublicKey,
1049 ) where L::Target: Logger {
1050 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1051 txid, htlc_outputs, commitment_number, their_revocation_point, logger)
1055 fn provide_latest_holder_commitment_tx(
1057 holder_commitment_tx: HolderCommitmentTransaction,
1058 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1059 ) -> Result<(), MonitorUpdateError> {
1060 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(
1061 holder_commitment_tx, htlc_outputs)
1065 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1067 payment_hash: &PaymentHash,
1068 payment_preimage: &PaymentPreimage,
1073 B::Target: BroadcasterInterface,
1074 F::Target: FeeEstimator,
1077 self.inner.lock().unwrap().provide_payment_preimage(
1078 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1081 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(
1086 B::Target: BroadcasterInterface,
1089 self.inner.lock().unwrap().broadcast_latest_holder_commitment_txn(broadcaster, logger)
1092 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1095 /// panics if the given update is not the next update by update_id.
1096 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1098 updates: &ChannelMonitorUpdate,
1102 ) -> Result<(), MonitorUpdateError>
1104 B::Target: BroadcasterInterface,
1105 F::Target: FeeEstimator,
1108 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1111 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1113 pub fn get_latest_update_id(&self) -> u64 {
1114 self.inner.lock().unwrap().get_latest_update_id()
1117 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1118 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1119 self.inner.lock().unwrap().get_funding_txo().clone()
1122 /// Gets a list of txids, with their output scripts (in the order they appear in the
1123 /// transaction), which we must learn about spends of via block_connected().
1124 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1125 self.inner.lock().unwrap().get_outputs_to_watch()
1126 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1129 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1130 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1131 /// have been registered.
1132 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1133 let lock = self.inner.lock().unwrap();
1134 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1135 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1136 for (index, script_pubkey) in outputs.iter() {
1137 assert!(*index <= u16::max_value() as u32);
1138 filter.register_output(WatchedOutput {
1140 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1141 script_pubkey: script_pubkey.clone(),
1147 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1148 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1149 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1150 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1153 /// Gets the list of pending events which were generated by previous actions, clearing the list
1156 /// This is called by ChainMonitor::get_and_clear_pending_events() and is equivalent to
1157 /// EventsProvider::get_and_clear_pending_events() except that it requires &mut self as we do
1158 /// no internal locking in ChannelMonitors.
1159 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1160 self.inner.lock().unwrap().get_and_clear_pending_events()
1163 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1164 self.inner.lock().unwrap().get_min_seen_secret()
1167 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1168 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1171 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1172 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1175 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1176 /// the Channel was out-of-date. You may use it to get a broadcastable holder toxic tx in case of
1177 /// fallen-behind, i.e when receiving a channel_reestablish with a proof that our counterparty side knows
1178 /// a higher revocation secret than the holder commitment number we are aware of. Broadcasting these
1179 /// transactions are UNSAFE, as they allow counterparty side to punish you. Nevertheless you may want to
1180 /// broadcast them if counterparty don't close channel with his higher commitment transaction after a
1181 /// substantial amount of time (a month or even a year) to get back funds. Best may be to contact
1182 /// out-of-band the other node operator to coordinate with him if option is available to you.
1183 /// In any-case, choice is up to the user.
1184 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1185 where L::Target: Logger {
1186 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1189 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1190 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1191 /// revoked commitment transaction.
1192 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1193 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1194 where L::Target: Logger {
1195 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1198 /// Processes transactions in a newly connected block, which may result in any of the following:
1199 /// - update the monitor's state against resolved HTLCs
1200 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1201 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1202 /// - detect settled outputs for later spending
1203 /// - schedule and bump any in-flight claims
1205 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1206 /// [`get_outputs_to_watch`].
1208 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1209 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1211 header: &BlockHeader,
1212 txdata: &TransactionData,
1217 ) -> Vec<TransactionOutputs>
1219 B::Target: BroadcasterInterface,
1220 F::Target: FeeEstimator,
1223 self.inner.lock().unwrap().block_connected(
1224 header, txdata, height, broadcaster, fee_estimator, logger)
1227 /// Determines if the disconnected block contained any transactions of interest and updates
1229 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1231 header: &BlockHeader,
1237 B::Target: BroadcasterInterface,
1238 F::Target: FeeEstimator,
1241 self.inner.lock().unwrap().block_disconnected(
1242 header, height, broadcaster, fee_estimator, logger)
1245 /// Processes transactions confirmed in a block with the given header and height, returning new
1246 /// outputs to watch. See [`block_connected`] for details.
1248 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1249 /// blocks. See [`chain::Confirm`] for calling expectations.
1251 /// [`block_connected`]: Self::block_connected
1252 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1254 header: &BlockHeader,
1255 txdata: &TransactionData,
1260 ) -> Vec<TransactionOutputs>
1262 B::Target: BroadcasterInterface,
1263 F::Target: FeeEstimator,
1266 self.inner.lock().unwrap().transactions_confirmed(
1267 header, txdata, height, broadcaster, fee_estimator, logger)
1270 /// Processes a transaction that was reorganized out of the chain.
1272 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1273 /// than blocks. See [`chain::Confirm`] for calling expectations.
1275 /// [`block_disconnected`]: Self::block_disconnected
1276 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1283 B::Target: BroadcasterInterface,
1284 F::Target: FeeEstimator,
1287 self.inner.lock().unwrap().transaction_unconfirmed(
1288 txid, broadcaster, fee_estimator, logger);
1291 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1292 /// [`block_connected`] for details.
1294 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1295 /// blocks. See [`chain::Confirm`] for calling expectations.
1297 /// [`block_connected`]: Self::block_connected
1298 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1300 header: &BlockHeader,
1305 ) -> Vec<TransactionOutputs>
1307 B::Target: BroadcasterInterface,
1308 F::Target: FeeEstimator,
1311 self.inner.lock().unwrap().best_block_updated(
1312 header, height, broadcaster, fee_estimator, logger)
1315 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1316 pub fn get_relevant_txids(&self) -> Vec<Txid> {
1317 let inner = self.inner.lock().unwrap();
1318 let mut txids: Vec<Txid> = inner.onchain_events_awaiting_threshold_conf
1320 .map(|entry| entry.txid)
1321 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1323 txids.sort_unstable();
1328 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1329 /// [`chain::Confirm`] interfaces.
1330 pub fn current_best_block(&self) -> BestBlock {
1331 self.inner.lock().unwrap().best_block.clone()
1334 /// Gets the balances in this channel which are either claimable by us if we were to
1335 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1338 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1339 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1340 /// balance, or until our counterparty has claimed the balance and accrued several
1341 /// confirmations on the claim transaction.
1343 /// Note that the balances available when you or your counterparty have broadcasted revoked
1344 /// state(s) may not be fully captured here.
1347 /// See [`Balance`] for additional details on the types of claimable balances which
1348 /// may be returned here and their meanings.
1349 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1350 let mut res = Vec::new();
1351 let us = self.inner.lock().unwrap();
1353 let mut confirmed_txid = us.funding_spend_confirmed;
1354 let mut pending_commitment_tx_conf_thresh = None;
1355 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1356 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1357 Some((event.txid, event.confirmation_threshold()))
1360 if let Some((txid, conf_thresh)) = funding_spend_pending {
1361 debug_assert!(us.funding_spend_confirmed.is_none(),
1362 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1363 confirmed_txid = Some(txid);
1364 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1367 macro_rules! walk_htlcs {
1368 ($holder_commitment: expr, $htlc_iter: expr) => {
1369 for htlc in $htlc_iter {
1370 if let Some(htlc_input_idx) = htlc.transaction_output_index {
1371 if us.htlcs_resolved_on_chain.iter().any(|v| v.input_idx == htlc_input_idx) {
1372 assert!(us.funding_spend_confirmed.is_some());
1373 } else if htlc.offered == $holder_commitment {
1374 // If the payment was outbound, check if there's an HTLCUpdate
1375 // indicating we have spent this HTLC with a timeout, claiming it back
1376 // and awaiting confirmations on it.
1377 let htlc_update_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1378 if let OnchainEvent::HTLCUpdate { input_idx: Some(input_idx), .. } = event.event {
1379 if input_idx == htlc_input_idx { Some(event.confirmation_threshold()) } else { None }
1382 if let Some(conf_thresh) = htlc_update_pending {
1383 res.push(Balance::ClaimableAwaitingConfirmations {
1384 claimable_amount_satoshis: htlc.amount_msat / 1000,
1385 confirmation_height: conf_thresh,
1388 res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
1389 claimable_amount_satoshis: htlc.amount_msat / 1000,
1390 claimable_height: htlc.cltv_expiry,
1393 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1394 // Otherwise (the payment was inbound), only expose it as claimable if
1395 // we know the preimage.
1396 // Note that if there is a pending claim, but it did not use the
1397 // preimage, we lost funds to our counterparty! We will then continue
1398 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1399 let htlc_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1400 if let OnchainEvent::HTLCSpendConfirmation { input_idx, preimage, .. } = event.event {
1401 if input_idx == htlc_input_idx {
1402 Some((event.confirmation_threshold(), preimage.is_some()))
1406 if let Some((conf_thresh, true)) = htlc_spend_pending {
1407 res.push(Balance::ClaimableAwaitingConfirmations {
1408 claimable_amount_satoshis: htlc.amount_msat / 1000,
1409 confirmation_height: conf_thresh,
1412 res.push(Balance::ContentiousClaimable {
1413 claimable_amount_satoshis: htlc.amount_msat / 1000,
1414 timeout_height: htlc.cltv_expiry,
1423 if let Some(txid) = confirmed_txid {
1424 let mut found_commitment_tx = false;
1425 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1426 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().map(|(a, _)| a));
1427 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1428 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1429 if let OnchainEvent::MaturingOutput {
1430 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1432 Some(descriptor.output.value)
1435 res.push(Balance::ClaimableAwaitingConfirmations {
1436 claimable_amount_satoshis: value,
1437 confirmation_height: conf_thresh,
1440 // If a counterparty commitment transaction is awaiting confirmation, we
1441 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1442 // confirmation with the same height or have never met our dust amount.
1445 found_commitment_tx = true;
1446 } else if txid == us.current_holder_commitment_tx.txid {
1447 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1448 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1449 res.push(Balance::ClaimableAwaitingConfirmations {
1450 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1451 confirmation_height: conf_thresh,
1454 found_commitment_tx = true;
1455 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1456 if txid == prev_commitment.txid {
1457 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1458 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1459 res.push(Balance::ClaimableAwaitingConfirmations {
1460 claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1461 confirmation_height: conf_thresh,
1464 found_commitment_tx = true;
1467 if !found_commitment_tx {
1468 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1469 // We blindly assume this is a cooperative close transaction here, and that
1470 // neither us nor our counterparty misbehaved. At worst we've under-estimated
1471 // the amount we can claim as we'll punish a misbehaving counterparty.
1472 res.push(Balance::ClaimableAwaitingConfirmations {
1473 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1474 confirmation_height: conf_thresh,
1478 // TODO: Add logic to provide claimable balances for counterparty broadcasting revoked
1481 let mut claimable_inbound_htlc_value_sat = 0;
1482 for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1483 if htlc.transaction_output_index.is_none() { continue; }
1485 res.push(Balance::MaybeClaimableHTLCAwaitingTimeout {
1486 claimable_amount_satoshis: htlc.amount_msat / 1000,
1487 claimable_height: htlc.cltv_expiry,
1489 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1490 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1493 res.push(Balance::ClaimableOnChannelClose {
1494 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1502 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
1503 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
1504 /// after ANTI_REORG_DELAY blocks.
1506 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
1507 /// are the commitment transactions which are generated by us. The off-chain state machine in
1508 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
1509 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
1510 /// included in a remote commitment transaction are failed back if they are not present in the
1511 /// broadcasted commitment transaction.
1513 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
1514 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
1515 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
1516 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
1517 macro_rules! fail_unbroadcast_htlcs {
1518 ($self: expr, $commitment_tx_type: expr, $commitment_tx_conf_height: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
1519 macro_rules! check_htlc_fails {
1520 ($txid: expr, $commitment_tx: expr) => {
1521 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
1522 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1523 if let &Some(ref source) = source_option {
1524 // Check if the HTLC is present in the commitment transaction that was
1525 // broadcast, but not if it was below the dust limit, which we should
1526 // fail backwards immediately as there is no way for us to learn the
1527 // payment_preimage.
1528 // Note that if the dust limit were allowed to change between
1529 // commitment transactions we'd want to be check whether *any*
1530 // broadcastable commitment transaction has the HTLC in it, but it
1531 // cannot currently change after channel initialization, so we don't
1533 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
1534 let mut matched_htlc = false;
1535 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
1536 if broadcast_htlc.transaction_output_index.is_some() && Some(&**source) == *broadcast_source {
1537 matched_htlc = true;
1541 if matched_htlc { continue; }
1542 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
1543 if entry.height != $commitment_tx_conf_height { return true; }
1545 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
1546 *update_source != **source
1551 let entry = OnchainEventEntry {
1553 height: $commitment_tx_conf_height,
1554 event: OnchainEvent::HTLCUpdate {
1555 source: (**source).clone(),
1556 payment_hash: htlc.payment_hash.clone(),
1557 onchain_value_satoshis: Some(htlc.amount_msat / 1000),
1561 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction, waiting for confirmation (at height {})",
1562 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type, entry.confirmation_threshold());
1563 $self.onchain_events_awaiting_threshold_conf.push(entry);
1569 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
1570 check_htlc_fails!(txid, "current");
1572 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
1573 check_htlc_fails!(txid, "previous");
1578 impl<Signer: Sign> ChannelMonitorImpl<Signer> {
1579 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
1580 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
1581 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
1582 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), MonitorUpdateError> {
1583 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
1584 return Err(MonitorUpdateError("Previous secret did not match new one"));
1587 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
1588 // events for now-revoked/fulfilled HTLCs.
1589 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
1590 for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
1595 if !self.payment_preimages.is_empty() {
1596 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
1597 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
1598 let min_idx = self.get_min_seen_secret();
1599 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
1601 self.payment_preimages.retain(|&k, _| {
1602 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
1603 if k == htlc.payment_hash {
1607 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
1608 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
1609 if k == htlc.payment_hash {
1614 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
1621 counterparty_hash_commitment_number.remove(&k);
1630 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 {
1631 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
1632 // so that a remote monitor doesn't learn anything unless there is a malicious close.
1633 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
1635 for &(ref htlc, _) in &htlc_outputs {
1636 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
1639 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
1640 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
1641 self.current_counterparty_commitment_txid = Some(txid);
1642 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
1643 self.current_counterparty_commitment_number = commitment_number;
1644 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
1645 match self.their_cur_revocation_points {
1646 Some(old_points) => {
1647 if old_points.0 == commitment_number + 1 {
1648 self.their_cur_revocation_points = Some((old_points.0, old_points.1, Some(their_revocation_point)));
1649 } else if old_points.0 == commitment_number + 2 {
1650 if let Some(old_second_point) = old_points.2 {
1651 self.their_cur_revocation_points = Some((old_points.0 - 1, old_second_point, Some(their_revocation_point)));
1653 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1656 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1660 self.their_cur_revocation_points = Some((commitment_number, their_revocation_point, None));
1663 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
1664 for htlc in htlc_outputs {
1665 if htlc.0.transaction_output_index.is_some() {
1671 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
1672 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
1673 /// is important that any clones of this channel monitor (including remote clones) by kept
1674 /// up-to-date as our holder commitment transaction is updated.
1675 /// Panics if set_on_holder_tx_csv has never been called.
1676 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>) -> Result<(), MonitorUpdateError> {
1677 // block for Rust 1.34 compat
1678 let mut new_holder_commitment_tx = {
1679 let trusted_tx = holder_commitment_tx.trust();
1680 let txid = trusted_tx.txid();
1681 let tx_keys = trusted_tx.keys();
1682 self.current_holder_commitment_number = trusted_tx.commitment_number();
1685 revocation_key: tx_keys.revocation_key,
1686 a_htlc_key: tx_keys.broadcaster_htlc_key,
1687 b_htlc_key: tx_keys.countersignatory_htlc_key,
1688 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1689 per_commitment_point: tx_keys.per_commitment_point,
1691 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
1692 feerate_per_kw: trusted_tx.feerate_per_kw(),
1695 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
1696 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
1697 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
1698 if self.holder_tx_signed {
1699 return Err(MonitorUpdateError("Latest holder commitment signed has already been signed, update is rejected"));
1704 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
1705 /// commitment_tx_infos which contain the payment hash have been revoked.
1706 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)
1707 where B::Target: BroadcasterInterface,
1708 F::Target: FeeEstimator,
1711 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
1713 // If the channel is force closed, try to claim the output from this preimage.
1714 // First check if a counterparty commitment transaction has been broadcasted:
1715 macro_rules! claim_htlcs {
1716 ($commitment_number: expr, $txid: expr) => {
1717 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs($commitment_number, $txid, None);
1718 self.onchain_tx_handler.update_claims_view(&Vec::new(), htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1721 if let Some(txid) = self.current_counterparty_commitment_txid {
1722 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1723 claim_htlcs!(*commitment_number, txid);
1727 if let Some(txid) = self.prev_counterparty_commitment_txid {
1728 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
1729 claim_htlcs!(*commitment_number, txid);
1734 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
1735 // claiming the HTLC output from each of the holder commitment transactions.
1736 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
1737 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
1738 // holder commitment transactions.
1739 if self.broadcasted_holder_revokable_script.is_some() {
1740 // Assume that the broadcasted commitment transaction confirmed in the current best
1741 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
1743 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
1744 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1745 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
1746 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
1747 self.onchain_tx_handler.update_claims_view(&Vec::new(), claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
1752 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
1753 where B::Target: BroadcasterInterface,
1756 for tx in self.get_latest_holder_commitment_txn(logger).iter() {
1757 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
1758 broadcaster.broadcast_transaction(tx);
1760 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
1763 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: &F, logger: &L) -> Result<(), MonitorUpdateError>
1764 where B::Target: BroadcasterInterface,
1765 F::Target: FeeEstimator,
1768 // ChannelMonitor updates may be applied after force close if we receive a
1769 // preimage for a broadcasted commitment transaction HTLC output that we'd
1770 // like to claim on-chain. If this is the case, we no longer have guaranteed
1771 // access to the monitor's update ID, so we use a sentinel value instead.
1772 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
1773 match updates.updates[0] {
1774 ChannelMonitorUpdateStep::PaymentPreimage { .. } => {},
1775 _ => panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage"),
1777 assert_eq!(updates.updates.len(), 1);
1778 } else if self.latest_update_id + 1 != updates.update_id {
1779 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
1781 for update in updates.updates.iter() {
1783 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs } => {
1784 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
1785 if self.lockdown_from_offchain { panic!(); }
1786 self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone())?
1788 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_revocation_point } => {
1789 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
1790 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_revocation_point, logger)
1792 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
1793 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
1794 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, fee_estimator, logger)
1796 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
1797 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
1798 self.provide_secret(*idx, *secret)?
1800 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
1801 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
1802 self.lockdown_from_offchain = true;
1803 if *should_broadcast {
1804 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
1805 } else if !self.holder_tx_signed {
1806 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");
1808 // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
1809 // will still give us a ChannelForceClosed event with !should_broadcast, but we
1810 // shouldn't print the scary warning above.
1811 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
1814 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
1815 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
1816 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
1817 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
1822 self.latest_update_id = updates.update_id;
1826 pub fn get_latest_update_id(&self) -> u64 {
1827 self.latest_update_id
1830 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
1834 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
1835 // If we've detected a counterparty commitment tx on chain, we must include it in the set
1836 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
1837 // its trivial to do, double-check that here.
1838 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
1839 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
1841 &self.outputs_to_watch
1844 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
1845 let mut ret = Vec::new();
1846 mem::swap(&mut ret, &mut self.pending_monitor_events);
1850 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
1851 let mut ret = Vec::new();
1852 mem::swap(&mut ret, &mut self.pending_events);
1856 /// Can only fail if idx is < get_min_seen_secret
1857 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
1858 self.commitment_secrets.get_secret(idx)
1861 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1862 self.commitment_secrets.get_min_seen_secret()
1865 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1866 self.current_counterparty_commitment_number
1869 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1870 self.current_holder_commitment_number
1873 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
1874 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
1875 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
1876 /// HTLC-Success/HTLC-Timeout transactions.
1877 /// Return updates for HTLC pending in the channel and failed automatically by the broadcast of
1878 /// revoked counterparty commitment tx
1879 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> (Vec<PackageTemplate>, TransactionOutputs) where L::Target: Logger {
1880 // Most secp and related errors trying to create keys means we have no hope of constructing
1881 // a spend transaction...so we return no transactions to broadcast
1882 let mut claimable_outpoints = Vec::new();
1883 let mut watch_outputs = Vec::new();
1885 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
1886 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
1888 macro_rules! ignore_error {
1889 ( $thing : expr ) => {
1892 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs))
1897 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);
1898 if commitment_number >= self.get_min_seen_secret() {
1899 let secret = self.get_secret(commitment_number).unwrap();
1900 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
1901 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
1902 let revocation_pubkey = ignore_error!(chan_utils::derive_public_revocation_key(&self.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint));
1903 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));
1905 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
1906 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
1908 // First, process non-htlc outputs (to_holder & to_counterparty)
1909 for (idx, outp) in tx.output.iter().enumerate() {
1910 if outp.script_pubkey == revokeable_p2wsh {
1911 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);
1912 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);
1913 claimable_outpoints.push(justice_package);
1917 // Then, try to find revoked htlc outputs
1918 if let Some(ref per_commitment_data) = per_commitment_option {
1919 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
1920 if let Some(transaction_output_index) = htlc.transaction_output_index {
1921 if transaction_output_index as usize >= tx.output.len() ||
1922 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1923 return (claimable_outpoints, (commitment_txid, watch_outputs)); // Corrupted per_commitment_data, fuck this user
1925 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());
1926 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, true, height);
1927 claimable_outpoints.push(justice_package);
1932 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
1933 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
1934 // We're definitely a counterparty commitment transaction!
1935 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
1936 for (idx, outp) in tx.output.iter().enumerate() {
1937 watch_outputs.push((idx as u32, outp.clone()));
1939 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1941 fail_unbroadcast_htlcs!(self, "revoked counterparty", height, [].iter().map(|a| *a), logger);
1943 } else if let Some(per_commitment_data) = per_commitment_option {
1944 // While this isn't useful yet, there is a potential race where if a counterparty
1945 // revokes a state at the same time as the commitment transaction for that state is
1946 // confirmed, and the watchtower receives the block before the user, the user could
1947 // upload a new ChannelMonitor with the revocation secret but the watchtower has
1948 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
1949 // not being generated by the above conditional. Thus, to be safe, we go ahead and
1951 for (idx, outp) in tx.output.iter().enumerate() {
1952 watch_outputs.push((idx as u32, outp.clone()));
1954 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
1956 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
1957 fail_unbroadcast_htlcs!(self, "counterparty", height, per_commitment_data.iter().map(|(a, b)| (a, b.as_ref().map(|b| b.as_ref()))), logger);
1959 let htlc_claim_reqs = self.get_counterparty_htlc_output_claim_reqs(commitment_number, commitment_txid, Some(tx));
1960 for req in htlc_claim_reqs {
1961 claimable_outpoints.push(req);
1965 (claimable_outpoints, (commitment_txid, watch_outputs))
1968 fn get_counterparty_htlc_output_claim_reqs(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>) -> Vec<PackageTemplate> {
1969 let mut claimable_outpoints = Vec::new();
1970 if let Some(htlc_outputs) = self.counterparty_claimable_outpoints.get(&commitment_txid) {
1971 if let Some(revocation_points) = self.their_cur_revocation_points {
1972 let revocation_point_option =
1973 // If the counterparty commitment tx is the latest valid state, use their latest
1974 // per-commitment point
1975 if revocation_points.0 == commitment_number { Some(&revocation_points.1) }
1976 else if let Some(point) = revocation_points.2.as_ref() {
1977 // If counterparty commitment tx is the state previous to the latest valid state, use
1978 // their previous per-commitment point (non-atomicity of revocation means it's valid for
1979 // them to temporarily have two valid commitment txns from our viewpoint)
1980 if revocation_points.0 == commitment_number + 1 { Some(point) } else { None }
1982 if let Some(revocation_point) = revocation_point_option {
1983 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
1984 if let Some(transaction_output_index) = htlc.transaction_output_index {
1985 if let Some(transaction) = tx {
1986 if transaction_output_index as usize >= transaction.output.len() ||
1987 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
1988 return claimable_outpoints; // Corrupted per_commitment_data, fuck this user
1991 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
1992 if preimage.is_some() || !htlc.offered {
1993 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())) };
1994 let aggregation = if !htlc.offered { false } else { true };
1995 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry,aggregation, 0);
1996 claimable_outpoints.push(counterparty_package);
2006 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2007 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 {
2008 let htlc_txid = tx.txid();
2009 if tx.input.len() != 1 || tx.output.len() != 1 || tx.input[0].witness.len() != 5 {
2010 return (Vec::new(), None)
2013 macro_rules! ignore_error {
2014 ( $thing : expr ) => {
2017 Err(_) => return (Vec::new(), None)
2022 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2023 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2024 let per_commitment_point = PublicKey::from_secret_key(&self.secp_ctx, &per_commitment_key);
2026 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, 0);
2027 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);
2028 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);
2029 let claimable_outpoints = vec!(justice_package);
2030 let outputs = vec![(0, tx.output[0].clone())];
2031 (claimable_outpoints, Some((htlc_txid, outputs)))
2034 // Returns (1) `PackageTemplate`s that can be given to the OnChainTxHandler, so that the handler can
2035 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2036 // script so we can detect whether a holder transaction has been seen on-chain.
2037 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2038 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2040 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2041 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2043 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2044 if let Some(transaction_output_index) = htlc.transaction_output_index {
2045 let htlc_output = if htlc.offered {
2046 HolderHTLCOutput::build_offered(htlc.amount_msat, htlc.cltv_expiry)
2048 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2051 // We can't build an HTLC-Success transaction without the preimage
2054 HolderHTLCOutput::build_accepted(payment_preimage, htlc.amount_msat)
2056 let htlc_package = PackageTemplate::build_package(holder_tx.txid, transaction_output_index, PackageSolvingData::HolderHTLCOutput(htlc_output), htlc.cltv_expiry, false, conf_height);
2057 claim_requests.push(htlc_package);
2061 (claim_requests, broadcasted_holder_revokable_script)
2064 // Returns holder HTLC outputs to watch and react to in case of spending.
2065 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2066 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2067 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2068 if let Some(transaction_output_index) = htlc.transaction_output_index {
2069 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2075 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2076 /// revoked using data in holder_claimable_outpoints.
2077 /// Should not be used if check_spend_revoked_transaction succeeds.
2078 /// Returns None unless the transaction is definitely one of our commitment transactions.
2079 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
2080 let commitment_txid = tx.txid();
2081 let mut claim_requests = Vec::new();
2082 let mut watch_outputs = Vec::new();
2084 macro_rules! append_onchain_update {
2085 ($updates: expr, $to_watch: expr) => {
2086 claim_requests = $updates.0;
2087 self.broadcasted_holder_revokable_script = $updates.1;
2088 watch_outputs.append(&mut $to_watch);
2092 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2093 let mut is_holder_tx = false;
2095 if self.current_holder_commitment_tx.txid == commitment_txid {
2096 is_holder_tx = true;
2097 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2098 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2099 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2100 append_onchain_update!(res, to_watch);
2101 fail_unbroadcast_htlcs!(self, "latest holder", height, self.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
2102 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2103 if holder_tx.txid == commitment_txid {
2104 is_holder_tx = true;
2105 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2106 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2107 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2108 append_onchain_update!(res, to_watch);
2109 fail_unbroadcast_htlcs!(self, "previous holder", height, holder_tx.htlc_outputs.iter().map(|(a, _, c)| (a, c.as_ref())), logger);
2114 Some((claim_requests, (commitment_txid, watch_outputs)))
2120 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2121 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2122 self.holder_tx_signed = true;
2123 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2124 let txid = commitment_tx.txid();
2125 let mut holder_transactions = vec![commitment_tx];
2126 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2127 if let Some(vout) = htlc.0.transaction_output_index {
2128 let preimage = if !htlc.0.offered {
2129 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2130 // We can't build an HTLC-Success transaction without the preimage
2133 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2134 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2135 // current locktime requirements on-chain. We will broadcast them in
2136 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2137 // Note that we add + 1 as transactions are broadcastable when they can be
2138 // confirmed in the next block.
2141 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2142 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2143 holder_transactions.push(htlc_tx);
2147 // 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.
2148 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2152 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2153 /// Note that this includes possibly-locktimed-in-the-future transactions!
2154 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2155 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2156 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2157 let txid = commitment_tx.txid();
2158 let mut holder_transactions = vec![commitment_tx];
2159 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2160 if let Some(vout) = htlc.0.transaction_output_index {
2161 let preimage = if !htlc.0.offered {
2162 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2163 // We can't build an HTLC-Success transaction without the preimage
2167 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
2168 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2169 holder_transactions.push(htlc_tx);
2176 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>
2177 where B::Target: BroadcasterInterface,
2178 F::Target: FeeEstimator,
2181 let block_hash = header.block_hash();
2182 self.best_block = BestBlock::new(block_hash, height);
2184 self.transactions_confirmed(header, txdata, height, broadcaster, fee_estimator, logger)
2187 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
2189 header: &BlockHeader,
2194 ) -> Vec<TransactionOutputs>
2196 B::Target: BroadcasterInterface,
2197 F::Target: FeeEstimator,
2200 let block_hash = header.block_hash();
2202 if height > self.best_block.height() {
2203 self.best_block = BestBlock::new(block_hash, height);
2204 self.block_confirmed(height, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
2205 } else if block_hash != self.best_block.block_hash() {
2206 self.best_block = BestBlock::new(block_hash, height);
2207 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
2208 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
2210 } else { Vec::new() }
2213 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
2215 header: &BlockHeader,
2216 txdata: &TransactionData,
2221 ) -> Vec<TransactionOutputs>
2223 B::Target: BroadcasterInterface,
2224 F::Target: FeeEstimator,
2227 let txn_matched = self.filter_block(txdata);
2228 for tx in &txn_matched {
2229 let mut output_val = 0;
2230 for out in tx.output.iter() {
2231 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2232 output_val += out.value;
2233 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
2237 let block_hash = header.block_hash();
2239 let mut watch_outputs = Vec::new();
2240 let mut claimable_outpoints = Vec::new();
2241 for tx in &txn_matched {
2242 if tx.input.len() == 1 {
2243 // Assuming our keys were not leaked (in which case we're screwed no matter what),
2244 // commitment transactions and HTLC transactions will all only ever have one input,
2245 // which is an easy way to filter out any potential non-matching txn for lazy
2247 let prevout = &tx.input[0].previous_output;
2248 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
2249 let mut balance_spendable_csv = None;
2250 log_info!(logger, "Channel closed by funding output spend in txid {}.", log_bytes!(tx.txid()));
2251 if (tx.input[0].sequence >> 8*3) as u8 == 0x80 && (tx.lock_time >> 8*3) as u8 == 0x20 {
2252 let (mut new_outpoints, new_outputs) = self.check_spend_counterparty_transaction(&tx, height, &logger);
2253 if !new_outputs.1.is_empty() {
2254 watch_outputs.push(new_outputs);
2256 claimable_outpoints.append(&mut new_outpoints);
2257 if new_outpoints.is_empty() {
2258 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &logger) {
2259 if !new_outputs.1.is_empty() {
2260 watch_outputs.push(new_outputs);
2262 claimable_outpoints.append(&mut new_outpoints);
2263 balance_spendable_csv = Some(self.on_holder_tx_csv);
2267 let txid = tx.txid();
2268 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2271 event: OnchainEvent::FundingSpendConfirmation {
2272 on_local_output_csv: balance_spendable_csv,
2276 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&prevout.txid) {
2277 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(&tx, commitment_number, height, &logger);
2278 claimable_outpoints.append(&mut new_outpoints);
2279 if let Some(new_outputs) = new_outputs_option {
2280 watch_outputs.push(new_outputs);
2285 // While all commitment/HTLC-Success/HTLC-Timeout transactions have one input, HTLCs
2286 // can also be resolved in a few other ways which can have more than one output. Thus,
2287 // we call is_resolving_htlc_output here outside of the tx.input.len() == 1 check.
2288 self.is_resolving_htlc_output(&tx, height, &logger);
2290 self.is_paying_spendable_output(&tx, height, &logger);
2293 if height > self.best_block.height() {
2294 self.best_block = BestBlock::new(block_hash, height);
2297 self.block_confirmed(height, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
2300 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
2301 /// `self.best_block` before calling if a new best blockchain tip is available. More
2302 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
2303 /// complexity especially in `OnchainTx::update_claims_view`.
2305 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
2306 /// confirmed at, even if it is not the current best height.
2307 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
2310 txn_matched: Vec<&Transaction>,
2311 mut watch_outputs: Vec<TransactionOutputs>,
2312 mut claimable_outpoints: Vec<PackageTemplate>,
2316 ) -> Vec<TransactionOutputs>
2318 B::Target: BroadcasterInterface,
2319 F::Target: FeeEstimator,
2322 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
2323 debug_assert!(self.best_block.height() >= conf_height);
2325 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
2326 if should_broadcast {
2327 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone());
2328 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());
2329 claimable_outpoints.push(commitment_package);
2330 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2331 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2332 self.holder_tx_signed = true;
2333 // Because we're broadcasting a commitment transaction, we should construct the package
2334 // assuming it gets confirmed in the next block. Sadly, we have code which considers
2335 // "not yet confirmed" things as discardable, so we cannot do that here.
2336 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2337 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
2338 if !new_outputs.is_empty() {
2339 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
2341 claimable_outpoints.append(&mut new_outpoints);
2344 // Find which on-chain events have reached their confirmation threshold.
2345 let onchain_events_awaiting_threshold_conf =
2346 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
2347 let mut onchain_events_reaching_threshold_conf = Vec::new();
2348 for entry in onchain_events_awaiting_threshold_conf {
2349 if entry.has_reached_confirmation_threshold(&self.best_block) {
2350 onchain_events_reaching_threshold_conf.push(entry);
2352 self.onchain_events_awaiting_threshold_conf.push(entry);
2356 // Used to check for duplicate HTLC resolutions.
2357 #[cfg(debug_assertions)]
2358 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
2360 .filter_map(|entry| match &entry.event {
2361 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
2365 #[cfg(debug_assertions)]
2366 let mut matured_htlcs = Vec::new();
2368 // Produce actionable events from on-chain events having reached their threshold.
2369 for entry in onchain_events_reaching_threshold_conf.drain(..) {
2371 OnchainEvent::HTLCUpdate { ref source, payment_hash, onchain_value_satoshis, input_idx } => {
2372 // Check for duplicate HTLC resolutions.
2373 #[cfg(debug_assertions)]
2376 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
2377 "An unmature HTLC transaction conflicts with a maturing one; failed to \
2378 call either transaction_unconfirmed for the conflicting transaction \
2379 or block_disconnected for a block containing it.");
2381 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
2382 "A matured HTLC transaction conflicts with a maturing one; failed to \
2383 call either transaction_unconfirmed for the conflicting transaction \
2384 or block_disconnected for a block containing it.");
2385 matured_htlcs.push(source.clone());
2388 log_debug!(logger, "HTLC {} failure update has got enough confirmations to be passed upstream", log_bytes!(payment_hash.0));
2389 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2391 payment_preimage: None,
2392 source: source.clone(),
2393 onchain_value_satoshis,
2395 if let Some(idx) = input_idx {
2396 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC { input_idx: idx, payment_preimage: None });
2399 OnchainEvent::MaturingOutput { descriptor } => {
2400 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
2401 self.pending_events.push(Event::SpendableOutputs {
2402 outputs: vec![descriptor]
2405 OnchainEvent::HTLCSpendConfirmation { input_idx, preimage, .. } => {
2406 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC { input_idx, payment_preimage: preimage });
2408 OnchainEvent::FundingSpendConfirmation { .. } => {
2409 self.funding_spend_confirmed = Some(entry.txid);
2414 self.onchain_tx_handler.update_claims_view(&txn_matched, claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
2416 // Determine new outputs to watch by comparing against previously known outputs to watch,
2417 // updating the latter in the process.
2418 watch_outputs.retain(|&(ref txid, ref txouts)| {
2419 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
2420 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
2424 // If we see a transaction for which we registered outputs previously,
2425 // make sure the registered scriptpubkey at the expected index match
2426 // the actual transaction output one. We failed this case before #653.
2427 for tx in &txn_matched {
2428 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
2429 for idx_and_script in outputs.iter() {
2430 assert!((idx_and_script.0 as usize) < tx.output.len());
2431 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
2439 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
2440 where B::Target: BroadcasterInterface,
2441 F::Target: FeeEstimator,
2444 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
2447 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
2448 //- maturing spendable output has transaction paying us has been disconnected
2449 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
2451 self.onchain_tx_handler.block_disconnected(height, broadcaster, fee_estimator, logger);
2453 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
2456 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
2463 B::Target: BroadcasterInterface,
2464 F::Target: FeeEstimator,
2467 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.txid != *txid);
2468 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
2471 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
2472 /// transactions thereof.
2473 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
2474 let mut matched_txn = HashSet::new();
2475 txdata.iter().filter(|&&(_, tx)| {
2476 let mut matches = self.spends_watched_output(tx);
2477 for input in tx.input.iter() {
2478 if matches { break; }
2479 if matched_txn.contains(&input.previous_output.txid) {
2484 matched_txn.insert(tx.txid());
2487 }).map(|(_, tx)| *tx).collect()
2490 /// Checks if a given transaction spends any watched outputs.
2491 fn spends_watched_output(&self, tx: &Transaction) -> bool {
2492 for input in tx.input.iter() {
2493 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
2494 for (idx, _script_pubkey) in outputs.iter() {
2495 if *idx == input.previous_output.vout {
2498 // If the expected script is a known type, check that the witness
2499 // appears to be spending the correct type (ie that the match would
2500 // actually succeed in BIP 158/159-style filters).
2501 if _script_pubkey.is_v0_p2wsh() {
2502 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().clone()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
2503 } else if _script_pubkey.is_v0_p2wpkh() {
2504 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
2505 } else { panic!(); }
2516 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
2517 // We need to consider all HTLCs which are:
2518 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
2519 // transactions and we'd end up in a race, or
2520 // * are in our latest holder commitment transaction, as this is the thing we will
2521 // broadcast if we go on-chain.
2522 // Note that we consider HTLCs which were below dust threshold here - while they don't
2523 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
2524 // to the source, and if we don't fail the channel we will have to ensure that the next
2525 // updates that peer sends us are update_fails, failing the channel if not. It's probably
2526 // easier to just fail the channel as this case should be rare enough anyway.
2527 let height = self.best_block.height();
2528 macro_rules! scan_commitment {
2529 ($htlcs: expr, $holder_tx: expr) => {
2530 for ref htlc in $htlcs {
2531 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
2532 // chain with enough room to claim the HTLC without our counterparty being able to
2533 // time out the HTLC first.
2534 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
2535 // concern is being able to claim the corresponding inbound HTLC (on another
2536 // channel) before it expires. In fact, we don't even really care if our
2537 // counterparty here claims such an outbound HTLC after it expired as long as we
2538 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
2539 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
2540 // we give ourselves a few blocks of headroom after expiration before going
2541 // on-chain for an expired HTLC.
2542 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
2543 // from us until we've reached the point where we go on-chain with the
2544 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
2545 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
2546 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
2547 // inbound_cltv == height + CLTV_CLAIM_BUFFER
2548 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
2549 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
2550 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
2551 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
2552 // The final, above, condition is checked for statically in channelmanager
2553 // with CHECK_CLTV_EXPIRY_SANITY_2.
2554 let htlc_outbound = $holder_tx == htlc.offered;
2555 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
2556 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
2557 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
2564 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
2566 if let Some(ref txid) = self.current_counterparty_commitment_txid {
2567 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2568 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2571 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
2572 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
2573 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
2580 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
2581 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
2582 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2583 'outer_loop: for input in &tx.input {
2584 let mut payment_data = None;
2585 let revocation_sig_claim = (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && input.witness[1].len() == 33)
2586 || (input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && input.witness[1].len() == 33);
2587 let accepted_preimage_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::AcceptedHTLC);
2588 #[cfg(not(fuzzing))]
2589 let accepted_timeout_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::AcceptedHTLC) && !revocation_sig_claim;
2590 let offered_preimage_claim = input.witness.len() == 3 && HTLCType::scriptlen_to_htlctype(input.witness[2].len()) == Some(HTLCType::OfferedHTLC) && !revocation_sig_claim;
2591 #[cfg(not(fuzzing))]
2592 let offered_timeout_claim = input.witness.len() == 5 && HTLCType::scriptlen_to_htlctype(input.witness[4].len()) == Some(HTLCType::OfferedHTLC);
2594 let mut payment_preimage = PaymentPreimage([0; 32]);
2595 if accepted_preimage_claim {
2596 payment_preimage.0.copy_from_slice(&input.witness[3]);
2597 } else if offered_preimage_claim {
2598 payment_preimage.0.copy_from_slice(&input.witness[1]);
2601 macro_rules! log_claim {
2602 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
2603 let outbound_htlc = $holder_tx == $htlc.offered;
2604 // HTLCs must either be claimed by a matching script type or through the
2606 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2607 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
2608 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2609 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
2610 // Further, only exactly one of the possible spend paths should have been
2611 // matched by any HTLC spend:
2612 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
2613 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
2614 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
2615 revocation_sig_claim as u8, 1);
2616 if ($holder_tx && revocation_sig_claim) ||
2617 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
2618 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
2619 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2620 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2621 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back" });
2623 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
2624 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
2625 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
2626 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
2631 macro_rules! check_htlc_valid_counterparty {
2632 ($counterparty_txid: expr, $htlc_output: expr) => {
2633 if let Some(txid) = $counterparty_txid {
2634 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2635 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
2636 if let &Some(ref source) = pending_source {
2637 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
2638 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
2647 macro_rules! scan_commitment {
2648 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
2649 for (ref htlc_output, source_option) in $htlcs {
2650 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
2651 if let Some(ref source) = source_option {
2652 log_claim!($tx_info, $holder_tx, htlc_output, true);
2653 // We have a resolution of an HTLC either from one of our latest
2654 // holder commitment transactions or an unrevoked counterparty commitment
2655 // transaction. This implies we either learned a preimage, the HTLC
2656 // has timed out, or we screwed up. In any case, we should now
2657 // resolve the source HTLC with the original sender.
2658 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
2659 } else if !$holder_tx {
2660 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
2661 if payment_data.is_none() {
2662 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
2665 if payment_data.is_none() {
2666 log_claim!($tx_info, $holder_tx, htlc_output, false);
2667 let outbound_htlc = $holder_tx == htlc_output.offered;
2668 if !outbound_htlc || revocation_sig_claim {
2669 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2670 txid: tx.txid(), height,
2671 event: OnchainEvent::HTLCSpendConfirmation {
2672 input_idx: input.previous_output.vout,
2673 preimage: if accepted_preimage_claim || offered_preimage_claim {
2674 Some(payment_preimage) } else { None },
2675 // If this is a payment to us (!outbound_htlc, above),
2676 // wait for the CSV delay before dropping the HTLC from
2677 // claimable balance if the claim was an HTLC-Success
2679 on_to_local_output_csv: if accepted_preimage_claim {
2680 Some(self.on_holder_tx_csv) } else { None },
2684 // Outbound claims should always have payment_data, unless
2685 // we've already failed the HTLC as the commitment transaction
2686 // which was broadcasted was revoked. In that case, we should
2687 // spend the HTLC output here immediately, and expose that fact
2688 // as a Balance, something which we do not yet do.
2689 // TODO: Track the above as claimable!
2691 continue 'outer_loop;
2698 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
2699 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2700 "our latest holder commitment tx", true);
2702 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
2703 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
2704 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
2705 "our previous holder commitment tx", true);
2708 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
2709 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
2710 "counterparty commitment tx", false);
2713 // Check that scan_commitment, above, decided there is some source worth relaying an
2714 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
2715 if let Some((source, payment_hash, amount_msat)) = payment_data {
2716 if accepted_preimage_claim {
2717 if !self.pending_monitor_events.iter().any(
2718 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
2719 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2722 event: OnchainEvent::HTLCSpendConfirmation {
2723 input_idx: input.previous_output.vout,
2724 preimage: Some(payment_preimage),
2725 on_to_local_output_csv: None,
2728 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2730 payment_preimage: Some(payment_preimage),
2732 onchain_value_satoshis: Some(amount_msat / 1000),
2735 } else if offered_preimage_claim {
2736 if !self.pending_monitor_events.iter().any(
2737 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
2738 upd.source == source
2740 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
2743 event: OnchainEvent::HTLCSpendConfirmation {
2744 input_idx: input.previous_output.vout,
2745 preimage: Some(payment_preimage),
2746 on_to_local_output_csv: None,
2749 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
2751 payment_preimage: Some(payment_preimage),
2753 onchain_value_satoshis: Some(amount_msat / 1000),
2757 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2758 if entry.height != height { return true; }
2760 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
2761 *htlc_source != source
2766 let entry = OnchainEventEntry {
2769 event: OnchainEvent::HTLCUpdate {
2770 source, payment_hash,
2771 onchain_value_satoshis: Some(amount_msat / 1000),
2772 input_idx: Some(input.previous_output.vout),
2775 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());
2776 self.onchain_events_awaiting_threshold_conf.push(entry);
2782 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
2783 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, logger: &L) where L::Target: Logger {
2784 let mut spendable_output = None;
2785 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
2786 if i > ::core::u16::MAX as usize {
2787 // While it is possible that an output exists on chain which is greater than the
2788 // 2^16th output in a given transaction, this is only possible if the output is not
2789 // in a lightning transaction and was instead placed there by some third party who
2790 // wishes to give us money for no reason.
2791 // Namely, any lightning transactions which we pre-sign will never have anywhere
2792 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
2793 // scripts are not longer than one byte in length and because they are inherently
2794 // non-standard due to their size.
2795 // Thus, it is completely safe to ignore such outputs, and while it may result in
2796 // us ignoring non-lightning fund to us, that is only possible if someone fills
2797 // nearly a full block with garbage just to hit this case.
2800 if outp.script_pubkey == self.destination_script {
2801 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2802 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2803 output: outp.clone(),
2807 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
2808 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
2809 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
2810 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2811 per_commitment_point: broadcasted_holder_revokable_script.1,
2812 to_self_delay: self.on_holder_tx_csv,
2813 output: outp.clone(),
2814 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
2815 channel_keys_id: self.channel_keys_id,
2816 channel_value_satoshis: self.channel_value_satoshis,
2821 if self.counterparty_payment_script == outp.script_pubkey {
2822 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
2823 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2824 output: outp.clone(),
2825 channel_keys_id: self.channel_keys_id,
2826 channel_value_satoshis: self.channel_value_satoshis,
2830 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
2831 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
2832 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
2833 output: outp.clone(),
2838 if let Some(spendable_output) = spendable_output {
2839 let entry = OnchainEventEntry {
2842 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
2844 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
2845 self.onchain_events_awaiting_threshold_conf.push(entry);
2850 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
2852 T::Target: BroadcasterInterface,
2853 F::Target: FeeEstimator,
2856 fn block_connected(&self, block: &Block, height: u32) {
2857 let txdata: Vec<_> = block.txdata.iter().enumerate().collect();
2858 self.0.block_connected(&block.header, &txdata, height, &*self.1, &*self.2, &*self.3);
2861 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
2862 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
2866 impl<Signer: Sign, T: Deref, F: Deref, L: Deref> chain::Confirm for (ChannelMonitor<Signer>, T, F, L)
2868 T::Target: BroadcasterInterface,
2869 F::Target: FeeEstimator,
2872 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
2873 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
2876 fn transaction_unconfirmed(&self, txid: &Txid) {
2877 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
2880 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
2881 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
2884 fn get_relevant_txids(&self) -> Vec<Txid> {
2885 self.0.get_relevant_txids()
2889 const MAX_ALLOC_SIZE: usize = 64*1024;
2891 impl<'a, Signer: Sign, K: KeysInterface<Signer = Signer>> ReadableArgs<&'a K>
2892 for (BlockHash, ChannelMonitor<Signer>) {
2893 fn read<R: io::Read>(reader: &mut R, keys_manager: &'a K) -> Result<Self, DecodeError> {
2894 macro_rules! unwrap_obj {
2898 Err(_) => return Err(DecodeError::InvalidValue),
2903 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
2905 let latest_update_id: u64 = Readable::read(reader)?;
2906 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
2908 let destination_script = Readable::read(reader)?;
2909 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
2911 let revokable_address = Readable::read(reader)?;
2912 let per_commitment_point = Readable::read(reader)?;
2913 let revokable_script = Readable::read(reader)?;
2914 Some((revokable_address, per_commitment_point, revokable_script))
2917 _ => return Err(DecodeError::InvalidValue),
2919 let counterparty_payment_script = Readable::read(reader)?;
2920 let shutdown_script = {
2921 let script = <Script as Readable>::read(reader)?;
2922 if script.is_empty() { None } else { Some(script) }
2925 let channel_keys_id = Readable::read(reader)?;
2926 let holder_revocation_basepoint = Readable::read(reader)?;
2927 // Technically this can fail and serialize fail a round-trip, but only for serialization of
2928 // barely-init'd ChannelMonitors that we can't do anything with.
2929 let outpoint = OutPoint {
2930 txid: Readable::read(reader)?,
2931 index: Readable::read(reader)?,
2933 let funding_info = (outpoint, Readable::read(reader)?);
2934 let current_counterparty_commitment_txid = Readable::read(reader)?;
2935 let prev_counterparty_commitment_txid = Readable::read(reader)?;
2937 let counterparty_commitment_params = Readable::read(reader)?;
2938 let funding_redeemscript = Readable::read(reader)?;
2939 let channel_value_satoshis = Readable::read(reader)?;
2941 let their_cur_revocation_points = {
2942 let first_idx = <U48 as Readable>::read(reader)?.0;
2946 let first_point = Readable::read(reader)?;
2947 let second_point_slice: [u8; 33] = Readable::read(reader)?;
2948 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
2949 Some((first_idx, first_point, None))
2951 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
2956 let on_holder_tx_csv: u16 = Readable::read(reader)?;
2958 let commitment_secrets = Readable::read(reader)?;
2960 macro_rules! read_htlc_in_commitment {
2963 let offered: bool = Readable::read(reader)?;
2964 let amount_msat: u64 = Readable::read(reader)?;
2965 let cltv_expiry: u32 = Readable::read(reader)?;
2966 let payment_hash: PaymentHash = Readable::read(reader)?;
2967 let transaction_output_index: Option<u32> = Readable::read(reader)?;
2969 HTLCOutputInCommitment {
2970 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
2976 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
2977 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
2978 for _ in 0..counterparty_claimable_outpoints_len {
2979 let txid: Txid = Readable::read(reader)?;
2980 let htlcs_count: u64 = Readable::read(reader)?;
2981 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
2982 for _ in 0..htlcs_count {
2983 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
2985 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
2986 return Err(DecodeError::InvalidValue);
2990 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
2991 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
2992 for _ in 0..counterparty_commitment_txn_on_chain_len {
2993 let txid: Txid = Readable::read(reader)?;
2994 let commitment_number = <U48 as Readable>::read(reader)?.0;
2995 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
2996 return Err(DecodeError::InvalidValue);
3000 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3001 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3002 for _ in 0..counterparty_hash_commitment_number_len {
3003 let payment_hash: PaymentHash = Readable::read(reader)?;
3004 let commitment_number = <U48 as Readable>::read(reader)?.0;
3005 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3006 return Err(DecodeError::InvalidValue);
3010 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3011 match <u8 as Readable>::read(reader)? {
3014 Some(Readable::read(reader)?)
3016 _ => return Err(DecodeError::InvalidValue),
3018 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3020 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3021 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3023 let payment_preimages_len: u64 = Readable::read(reader)?;
3024 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3025 for _ in 0..payment_preimages_len {
3026 let preimage: PaymentPreimage = Readable::read(reader)?;
3027 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3028 if let Some(_) = payment_preimages.insert(hash, preimage) {
3029 return Err(DecodeError::InvalidValue);
3033 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3034 let mut pending_monitor_events = Some(
3035 Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
3036 for _ in 0..pending_monitor_events_len {
3037 let ev = match <u8 as Readable>::read(reader)? {
3038 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3039 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0),
3040 _ => return Err(DecodeError::InvalidValue)
3042 pending_monitor_events.as_mut().unwrap().push(ev);
3045 let pending_events_len: u64 = Readable::read(reader)?;
3046 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3047 for _ in 0..pending_events_len {
3048 if let Some(event) = MaybeReadable::read(reader)? {
3049 pending_events.push(event);
3053 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
3055 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
3056 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
3057 for _ in 0..waiting_threshold_conf_len {
3058 if let Some(val) = MaybeReadable::read(reader)? {
3059 onchain_events_awaiting_threshold_conf.push(val);
3063 let outputs_to_watch_len: u64 = Readable::read(reader)?;
3064 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>>())));
3065 for _ in 0..outputs_to_watch_len {
3066 let txid = Readable::read(reader)?;
3067 let outputs_len: u64 = Readable::read(reader)?;
3068 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
3069 for _ in 0..outputs_len {
3070 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
3072 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
3073 return Err(DecodeError::InvalidValue);
3076 let onchain_tx_handler: OnchainTxHandler<Signer> = ReadableArgs::read(reader, keys_manager)?;
3078 let lockdown_from_offchain = Readable::read(reader)?;
3079 let holder_tx_signed = Readable::read(reader)?;
3081 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
3082 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
3083 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
3084 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
3085 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
3086 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
3087 return Err(DecodeError::InvalidValue);
3091 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
3092 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
3093 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
3094 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
3095 return Err(DecodeError::InvalidValue);
3098 let mut funding_spend_confirmed = None;
3099 let mut htlcs_resolved_on_chain = Some(Vec::new());
3100 read_tlv_fields!(reader, {
3101 (1, funding_spend_confirmed, option),
3102 (3, htlcs_resolved_on_chain, vec_type),
3103 (5, pending_monitor_events, vec_type),
3106 let mut secp_ctx = Secp256k1::new();
3107 secp_ctx.seeded_randomize(&keys_manager.get_secure_random_bytes());
3109 Ok((best_block.block_hash(), ChannelMonitor {
3110 inner: Mutex::new(ChannelMonitorImpl {
3112 commitment_transaction_number_obscure_factor,
3115 broadcasted_holder_revokable_script,
3116 counterparty_payment_script,
3120 holder_revocation_basepoint,
3122 current_counterparty_commitment_txid,
3123 prev_counterparty_commitment_txid,
3125 counterparty_commitment_params,
3126 funding_redeemscript,
3127 channel_value_satoshis,
3128 their_cur_revocation_points,
3133 counterparty_claimable_outpoints,
3134 counterparty_commitment_txn_on_chain,
3135 counterparty_hash_commitment_number,
3137 prev_holder_signed_commitment_tx,
3138 current_holder_commitment_tx,
3139 current_counterparty_commitment_number,
3140 current_holder_commitment_number,
3143 pending_monitor_events: pending_monitor_events.unwrap(),
3146 onchain_events_awaiting_threshold_conf,
3151 lockdown_from_offchain,
3153 funding_spend_confirmed,
3154 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
3166 use bitcoin::blockdata::script::{Script, Builder};
3167 use bitcoin::blockdata::opcodes;
3168 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, SigHashType};
3169 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
3170 use bitcoin::util::bip143;
3171 use bitcoin::hashes::Hash;
3172 use bitcoin::hashes::sha256::Hash as Sha256;
3173 use bitcoin::hashes::hex::FromHex;
3174 use bitcoin::hash_types::Txid;
3175 use bitcoin::network::constants::Network;
3177 use chain::BestBlock;
3178 use chain::channelmonitor::ChannelMonitor;
3179 use chain::package::{WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC, WEIGHT_REVOKED_OUTPUT};
3180 use chain::transaction::OutPoint;
3181 use ln::{PaymentPreimage, PaymentHash};
3183 use ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
3184 use ln::script::ShutdownScript;
3185 use util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
3186 use bitcoin::secp256k1::key::{SecretKey,PublicKey};
3187 use bitcoin::secp256k1::Secp256k1;
3188 use sync::{Arc, Mutex};
3189 use chain::keysinterface::InMemorySigner;
3193 fn test_prune_preimages() {
3194 let secp_ctx = Secp256k1::new();
3195 let logger = Arc::new(TestLogger::new());
3196 let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
3197 let fee_estimator = Arc::new(TestFeeEstimator { sat_per_kw: Mutex::new(253) });
3199 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3200 let dummy_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3202 let mut preimages = Vec::new();
3205 let preimage = PaymentPreimage([i; 32]);
3206 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3207 preimages.push((preimage, hash));
3211 macro_rules! preimages_slice_to_htlc_outputs {
3212 ($preimages_slice: expr) => {
3214 let mut res = Vec::new();
3215 for (idx, preimage) in $preimages_slice.iter().enumerate() {
3216 res.push((HTLCOutputInCommitment {
3220 payment_hash: preimage.1.clone(),
3221 transaction_output_index: Some(idx as u32),
3228 macro_rules! preimages_to_holder_htlcs {
3229 ($preimages_slice: expr) => {
3231 let mut inp = preimages_slice_to_htlc_outputs!($preimages_slice);
3232 let res: Vec<_> = inp.drain(..).map(|e| { (e.0, None, e.1) }).collect();
3238 macro_rules! test_preimages_exist {
3239 ($preimages_slice: expr, $monitor: expr) => {
3240 for preimage in $preimages_slice {
3241 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
3246 let keys = InMemorySigner::new(
3248 SecretKey::from_slice(&[41; 32]).unwrap(),
3249 SecretKey::from_slice(&[41; 32]).unwrap(),
3250 SecretKey::from_slice(&[41; 32]).unwrap(),
3251 SecretKey::from_slice(&[41; 32]).unwrap(),
3252 SecretKey::from_slice(&[41; 32]).unwrap(),
3258 let counterparty_pubkeys = ChannelPublicKeys {
3259 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
3260 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
3261 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
3262 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
3263 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
3265 let funding_outpoint = OutPoint { txid: Default::default(), index: u16::max_value() };
3266 let channel_parameters = ChannelTransactionParameters {
3267 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
3268 holder_selected_contest_delay: 66,
3269 is_outbound_from_holder: true,
3270 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
3271 pubkeys: counterparty_pubkeys,
3272 selected_contest_delay: 67,
3274 funding_outpoint: Some(funding_outpoint),
3276 // Prune with one old state and a holder commitment tx holding a few overlaps with the
3278 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
3279 let best_block = BestBlock::from_genesis(Network::Testnet);
3280 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
3281 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
3282 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
3283 &channel_parameters,
3284 Script::new(), 46, 0,
3285 HolderCommitmentTransaction::dummy(), best_block);
3287 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
3288 let dummy_txid = dummy_tx.txid();
3289 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
3290 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
3291 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
3292 monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
3293 for &(ref preimage, ref hash) in preimages.iter() {
3294 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &fee_estimator, &logger);
3297 // Now provide a secret, pruning preimages 10-15
3298 let mut secret = [0; 32];
3299 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
3300 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
3301 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
3302 test_preimages_exist!(&preimages[0..10], monitor);
3303 test_preimages_exist!(&preimages[15..20], monitor);
3305 // Now provide a further secret, pruning preimages 15-17
3306 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
3307 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
3308 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
3309 test_preimages_exist!(&preimages[0..10], monitor);
3310 test_preimages_exist!(&preimages[17..20], monitor);
3312 // Now update holder commitment tx info, pruning only element 18 as we still care about the
3313 // previous commitment tx's preimages too
3314 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();
3315 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
3316 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
3317 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
3318 test_preimages_exist!(&preimages[0..10], monitor);
3319 test_preimages_exist!(&preimages[18..20], monitor);
3321 // But if we do it again, we'll prune 5-10
3322 monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..3])).unwrap();
3323 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
3324 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
3325 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
3326 test_preimages_exist!(&preimages[0..5], monitor);
3330 fn test_claim_txn_weight_computation() {
3331 // We test Claim txn weight, knowing that we want expected weigth and
3332 // not actual case to avoid sigs and time-lock delays hell variances.
3334 let secp_ctx = Secp256k1::new();
3335 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
3336 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
3337 let mut sum_actual_sigs = 0;
3339 macro_rules! sign_input {
3340 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr) => {
3341 let htlc = HTLCOutputInCommitment {
3342 offered: if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_OFFERED_HTLC { true } else { false },
3344 cltv_expiry: 2 << 16,
3345 payment_hash: PaymentHash([1; 32]),
3346 transaction_output_index: Some($idx as u32),
3348 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, &pubkey, &pubkey, &pubkey) };
3349 let sighash = hash_to_message!(&$sighash_parts.signature_hash($idx, &redeem_script, $amount, SigHashType::All)[..]);
3350 let sig = secp_ctx.sign(&sighash, &privkey);
3351 $sighash_parts.access_witness($idx).push(sig.serialize_der().to_vec());
3352 $sighash_parts.access_witness($idx)[0].push(SigHashType::All as u8);
3353 sum_actual_sigs += $sighash_parts.access_witness($idx)[0].len();
3354 if *$weight == WEIGHT_REVOKED_OUTPUT {
3355 $sighash_parts.access_witness($idx).push(vec!(1));
3356 } else if *$weight == WEIGHT_REVOKED_OFFERED_HTLC || *$weight == WEIGHT_REVOKED_RECEIVED_HTLC {
3357 $sighash_parts.access_witness($idx).push(pubkey.clone().serialize().to_vec());
3358 } else if *$weight == WEIGHT_RECEIVED_HTLC {
3359 $sighash_parts.access_witness($idx).push(vec![0]);
3361 $sighash_parts.access_witness($idx).push(PaymentPreimage([1; 32]).0.to_vec());
3363 $sighash_parts.access_witness($idx).push(redeem_script.into_bytes());
3364 println!("witness[0] {}", $sighash_parts.access_witness($idx)[0].len());
3365 println!("witness[1] {}", $sighash_parts.access_witness($idx)[1].len());
3366 println!("witness[2] {}", $sighash_parts.access_witness($idx)[2].len());
3370 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
3371 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
3373 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
3374 let mut claim_tx = Transaction { version: 0, lock_time: 0, input: Vec::new(), output: Vec::new() };
3376 claim_tx.input.push(TxIn {
3377 previous_output: BitcoinOutPoint {
3381 script_sig: Script::new(),
3382 sequence: 0xfffffffd,
3383 witness: Vec::new(),
3386 claim_tx.output.push(TxOut {
3387 script_pubkey: script_pubkey.clone(),
3390 let base_weight = claim_tx.get_weight();
3391 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_OFFERED_HTLC, WEIGHT_REVOKED_RECEIVED_HTLC];
3392 let mut inputs_total_weight = 2; // count segwit flags
3394 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3395 for (idx, inp) in inputs_weight.iter().enumerate() {
3396 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3397 inputs_total_weight += inp;
3400 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3402 // Claim tx with 1 offered HTLCs, 3 received HTLCs
3403 claim_tx.input.clear();
3404 sum_actual_sigs = 0;
3406 claim_tx.input.push(TxIn {
3407 previous_output: BitcoinOutPoint {
3411 script_sig: Script::new(),
3412 sequence: 0xfffffffd,
3413 witness: Vec::new(),
3416 let base_weight = claim_tx.get_weight();
3417 let inputs_weight = vec![WEIGHT_OFFERED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC, WEIGHT_RECEIVED_HTLC];
3418 let mut inputs_total_weight = 2; // count segwit flags
3420 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3421 for (idx, inp) in inputs_weight.iter().enumerate() {
3422 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3423 inputs_total_weight += inp;
3426 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
3428 // Justice tx with 1 revoked HTLC-Success tx output
3429 claim_tx.input.clear();
3430 sum_actual_sigs = 0;
3431 claim_tx.input.push(TxIn {
3432 previous_output: BitcoinOutPoint {
3436 script_sig: Script::new(),
3437 sequence: 0xfffffffd,
3438 witness: Vec::new(),
3440 let base_weight = claim_tx.get_weight();
3441 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
3442 let mut inputs_total_weight = 2; // count segwit flags
3444 let mut sighash_parts = bip143::SigHashCache::new(&mut claim_tx);
3445 for (idx, inp) in inputs_weight.iter().enumerate() {
3446 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs);
3447 inputs_total_weight += inp;
3450 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.get_weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
3453 // Further testing is done in the ChannelManager integration tests.