1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE
5 // or http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your option.
7 // You may not use this file except in accordance with one or both of these
10 //! The logic to monitor for on-chain transactions and create the relevant claim responses lives
13 //! ChannelMonitor objects are generated by ChannelManager in response to relevant
14 //! messages/actions, and MUST be persisted to disk (and, preferably, remotely) before progress can
15 //! be made in responding to certain messages, see [`chain::Watch`] for more.
17 //! Note that ChannelMonitors are an important part of the lightning trust model and a copy of the
18 //! latest ChannelMonitor must always be actively monitoring for chain updates (and no out-of-date
19 //! ChannelMonitors should do so). Thus, if you're building rust-lightning into an HSM or other
20 //! security-domain-separated system design, you should consider having multiple paths for
21 //! ChannelMonitors to get out of the HSM and onto monitoring devices.
23 use bitcoin::blockdata::block::BlockHeader;
24 use bitcoin::blockdata::transaction::{OutPoint as BitcoinOutPoint, TxOut, Transaction};
25 use bitcoin::blockdata::script::{Script, 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, ecdsa::Signature};
33 use bitcoin::secp256k1::{SecretKey, PublicKey};
34 use bitcoin::secp256k1;
36 use crate::ln::{PaymentHash, PaymentPreimage};
37 use crate::ln::msgs::DecodeError;
38 use crate::ln::chan_utils;
39 use crate::ln::chan_utils::{CounterpartyCommitmentSecrets, HTLCOutputInCommitment, HTLCClaim, ChannelTransactionParameters, HolderCommitmentTransaction};
40 use crate::ln::channelmanager::{HTLCSource, SentHTLCId};
42 use crate::chain::{BestBlock, WatchedOutput};
43 use crate::chain::chaininterface::{BroadcasterInterface, FeeEstimator, LowerBoundedFeeEstimator};
44 use crate::chain::transaction::{OutPoint, TransactionData};
45 use crate::sign::{SpendableOutputDescriptor, StaticPaymentOutputDescriptor, DelayedPaymentOutputDescriptor, WriteableEcdsaChannelSigner, SignerProvider, EntropySource};
46 use crate::chain::onchaintx::{ClaimEvent, OnchainTxHandler};
47 use crate::chain::package::{CounterpartyOfferedHTLCOutput, CounterpartyReceivedHTLCOutput, HolderFundingOutput, HolderHTLCOutput, PackageSolvingData, PackageTemplate, RevokedOutput, RevokedHTLCOutput};
48 use crate::chain::Filter;
49 use crate::util::logger::Logger;
50 use crate::util::ser::{Readable, ReadableArgs, RequiredWrapper, MaybeReadable, UpgradableRequired, Writer, Writeable, U48};
51 use crate::util::byte_utils;
52 use crate::events::Event;
53 use crate::events::bump_transaction::{AnchorDescriptor, HTLCDescriptor, BumpTransactionEvent};
55 use crate::prelude::*;
57 use crate::io::{self, Error};
58 use core::convert::TryInto;
60 use crate::sync::{Mutex, LockTestExt};
62 /// An update generated by the underlying channel itself which contains some new information the
63 /// [`ChannelMonitor`] should be made aware of.
65 /// Because this represents only a small number of updates to the underlying state, it is generally
66 /// much smaller than a full [`ChannelMonitor`]. However, for large single commitment transaction
67 /// updates (e.g. ones during which there are hundreds of HTLCs pending on the commitment
68 /// transaction), a single update may reach upwards of 1 MiB in serialized size.
69 #[derive(Clone, PartialEq, Eq)]
71 pub struct ChannelMonitorUpdate {
72 pub(crate) updates: Vec<ChannelMonitorUpdateStep>,
73 /// The sequence number of this update. Updates *must* be replayed in-order according to this
74 /// sequence number (and updates may panic if they are not). The update_id values are strictly
75 /// increasing and increase by one for each new update, with two exceptions specified below.
77 /// This sequence number is also used to track up to which points updates which returned
78 /// [`ChannelMonitorUpdateStatus::InProgress`] have been applied to all copies of a given
79 /// ChannelMonitor when ChannelManager::channel_monitor_updated is called.
81 /// The only instances we allow where update_id values are not strictly increasing have a
82 /// special update ID of [`CLOSED_CHANNEL_UPDATE_ID`]. This update ID is used for updates that
83 /// will force close the channel by broadcasting the latest commitment transaction or
84 /// special post-force-close updates, like providing preimages necessary to claim outputs on the
85 /// broadcast commitment transaction. See its docs for more details.
87 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
91 /// The update ID used for a [`ChannelMonitorUpdate`] that is either:
93 /// (1) attempting to force close the channel by broadcasting our latest commitment transaction or
94 /// (2) providing a preimage (after the channel has been force closed) from a forward link that
95 /// allows us to spend an HTLC output on this channel's (the backward link's) broadcasted
96 /// commitment transaction.
98 /// No other [`ChannelMonitorUpdate`]s are allowed after force-close.
99 pub const CLOSED_CHANNEL_UPDATE_ID: u64 = core::u64::MAX;
101 impl Writeable for ChannelMonitorUpdate {
102 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
103 write_ver_prefix!(w, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
104 self.update_id.write(w)?;
105 (self.updates.len() as u64).write(w)?;
106 for update_step in self.updates.iter() {
107 update_step.write(w)?;
109 write_tlv_fields!(w, {});
113 impl Readable for ChannelMonitorUpdate {
114 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
115 let _ver = read_ver_prefix!(r, SERIALIZATION_VERSION);
116 let update_id: u64 = Readable::read(r)?;
117 let len: u64 = Readable::read(r)?;
118 let mut updates = Vec::with_capacity(cmp::min(len as usize, MAX_ALLOC_SIZE / ::core::mem::size_of::<ChannelMonitorUpdateStep>()));
120 if let Some(upd) = MaybeReadable::read(r)? {
124 read_tlv_fields!(r, {});
125 Ok(Self { update_id, updates })
129 /// An event to be processed by the ChannelManager.
130 #[derive(Clone, PartialEq, Eq)]
131 pub enum MonitorEvent {
132 /// A monitor event containing an HTLCUpdate.
133 HTLCEvent(HTLCUpdate),
135 /// A monitor event that the Channel's commitment transaction was confirmed.
136 CommitmentTxConfirmed(OutPoint),
138 /// Indicates a [`ChannelMonitor`] update has completed. See
139 /// [`ChannelMonitorUpdateStatus::InProgress`] for more information on how this is used.
141 /// [`ChannelMonitorUpdateStatus::InProgress`]: super::ChannelMonitorUpdateStatus::InProgress
143 /// The funding outpoint of the [`ChannelMonitor`] that was updated
144 funding_txo: OutPoint,
145 /// The Update ID from [`ChannelMonitorUpdate::update_id`] which was applied or
146 /// [`ChannelMonitor::get_latest_update_id`].
148 /// Note that this should only be set to a given update's ID if all previous updates for the
149 /// same [`ChannelMonitor`] have been applied and persisted.
150 monitor_update_id: u64,
153 /// Indicates a [`ChannelMonitor`] update has failed. See
154 /// [`ChannelMonitorUpdateStatus::PermanentFailure`] for more information on how this is used.
156 /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
157 UpdateFailed(OutPoint),
159 impl_writeable_tlv_based_enum_upgradable!(MonitorEvent,
160 // Note that Completed and UpdateFailed are currently never serialized to disk as they are
161 // generated only in ChainMonitor
163 (0, funding_txo, required),
164 (2, monitor_update_id, required),
168 (4, CommitmentTxConfirmed),
172 /// Simple structure sent back by `chain::Watch` when an HTLC from a forward channel is detected on
173 /// chain. Used to update the corresponding HTLC in the backward channel. Failing to pass the
174 /// preimage claim backward will lead to loss of funds.
175 #[derive(Clone, PartialEq, Eq)]
176 pub struct HTLCUpdate {
177 pub(crate) payment_hash: PaymentHash,
178 pub(crate) payment_preimage: Option<PaymentPreimage>,
179 pub(crate) source: HTLCSource,
180 pub(crate) htlc_value_satoshis: Option<u64>,
182 impl_writeable_tlv_based!(HTLCUpdate, {
183 (0, payment_hash, required),
184 (1, htlc_value_satoshis, option),
185 (2, source, required),
186 (4, payment_preimage, option),
189 /// If an HTLC expires within this many blocks, don't try to claim it in a shared transaction,
190 /// instead claiming it in its own individual transaction.
191 pub(crate) const CLTV_SHARED_CLAIM_BUFFER: u32 = 12;
192 /// If an HTLC expires within this many blocks, force-close the channel to broadcast the
193 /// HTLC-Success transaction.
194 /// In other words, this is an upper bound on how many blocks we think it can take us to get a
195 /// transaction confirmed (and we use it in a few more, equivalent, places).
196 pub(crate) const CLTV_CLAIM_BUFFER: u32 = 18;
197 /// Number of blocks by which point we expect our counterparty to have seen new blocks on the
198 /// network and done a full update_fail_htlc/commitment_signed dance (+ we've updated all our
199 /// copies of ChannelMonitors, including watchtowers). We could enforce the contract by failing
200 /// at CLTV expiration height but giving a grace period to our peer may be profitable for us if he
201 /// can provide an over-late preimage. Nevertheless, grace period has to be accounted in our
202 /// CLTV_EXPIRY_DELTA to be secure. Following this policy we may decrease the rate of channel failures
203 /// due to expiration but increase the cost of funds being locked longuer in case of failure.
204 /// This delay also cover a low-power peer being slow to process blocks and so being behind us on
205 /// accurate block height.
206 /// In case of onchain failure to be pass backward we may see the last block of ANTI_REORG_DELAY
207 /// with at worst this delay, so we are not only using this value as a mercy for them but also
208 /// us as a safeguard to delay with enough time.
209 pub(crate) const LATENCY_GRACE_PERIOD_BLOCKS: u32 = 3;
210 /// Number of blocks we wait on seeing a HTLC output being solved before we fail corresponding
211 /// inbound HTLCs. This prevents us from failing backwards and then getting a reorg resulting in us
214 /// Note that this is a library-wide security assumption. If a reorg deeper than this number of
215 /// blocks occurs, counterparties may be able to steal funds or claims made by and balances exposed
216 /// by a [`ChannelMonitor`] may be incorrect.
217 // We also use this delay to be sure we can remove our in-flight claim txn from bump candidates buffer.
218 // It may cause spurious generation of bumped claim txn but that's alright given the outpoint is already
219 // solved by a previous claim tx. What we want to avoid is reorg evicting our claim tx and us not
220 // keep bumping another claim tx to solve the outpoint.
221 pub const ANTI_REORG_DELAY: u32 = 6;
222 /// Number of blocks before confirmation at which we fail back an un-relayed HTLC or at which we
223 /// refuse to accept a new HTLC.
225 /// This is used for a few separate purposes:
226 /// 1) if we've received an MPP HTLC to us and it expires within this many blocks and we are
227 /// waiting on additional parts (or waiting on the preimage for any HTLC from the user), we will
229 /// 2) if we receive an HTLC within this many blocks of its expiry (plus one to avoid a race
230 /// condition with the above), we will fail this HTLC without telling the user we received it,
232 /// (1) is all about protecting us - we need enough time to update the channel state before we hit
233 /// CLTV_CLAIM_BUFFER, at which point we'd go on chain to claim the HTLC with the preimage.
235 /// (2) is the same, but with an additional buffer to avoid accepting an HTLC which is immediately
236 /// in a race condition between the user connecting a block (which would fail it) and the user
237 /// providing us the preimage (which would claim it).
238 pub(crate) const HTLC_FAIL_BACK_BUFFER: u32 = CLTV_CLAIM_BUFFER + LATENCY_GRACE_PERIOD_BLOCKS;
240 // TODO(devrandom) replace this with HolderCommitmentTransaction
241 #[derive(Clone, PartialEq, Eq)]
242 struct HolderSignedTx {
243 /// txid of the transaction in tx, just used to make comparison faster
245 revocation_key: PublicKey,
246 a_htlc_key: PublicKey,
247 b_htlc_key: PublicKey,
248 delayed_payment_key: PublicKey,
249 per_commitment_point: PublicKey,
250 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
251 to_self_value_sat: u64,
254 impl_writeable_tlv_based!(HolderSignedTx, {
256 // Note that this is filled in with data from OnchainTxHandler if it's missing.
257 // For HolderSignedTx objects serialized with 0.0.100+, this should be filled in.
258 (1, to_self_value_sat, (default_value, u64::max_value())),
259 (2, revocation_key, required),
260 (4, a_htlc_key, required),
261 (6, b_htlc_key, required),
262 (8, delayed_payment_key, required),
263 (10, per_commitment_point, required),
264 (12, feerate_per_kw, required),
265 (14, htlc_outputs, required_vec)
268 impl HolderSignedTx {
269 fn non_dust_htlcs(&self) -> Vec<HTLCOutputInCommitment> {
270 self.htlc_outputs.iter().filter_map(|(htlc, _, _)| {
271 if let Some(_) = htlc.transaction_output_index {
281 /// We use this to track static counterparty commitment transaction data and to generate any
282 /// justice or 2nd-stage preimage/timeout transactions.
283 #[derive(PartialEq, Eq)]
284 struct CounterpartyCommitmentParameters {
285 counterparty_delayed_payment_base_key: PublicKey,
286 counterparty_htlc_base_key: PublicKey,
287 on_counterparty_tx_csv: u16,
290 impl Writeable for CounterpartyCommitmentParameters {
291 fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
292 w.write_all(&(0 as u64).to_be_bytes())?;
293 write_tlv_fields!(w, {
294 (0, self.counterparty_delayed_payment_base_key, required),
295 (2, self.counterparty_htlc_base_key, required),
296 (4, self.on_counterparty_tx_csv, required),
301 impl Readable for CounterpartyCommitmentParameters {
302 fn read<R: io::Read>(r: &mut R) -> Result<Self, DecodeError> {
303 let counterparty_commitment_transaction = {
304 // Versions prior to 0.0.100 had some per-HTLC state stored here, which is no longer
305 // used. Read it for compatibility.
306 let per_htlc_len: u64 = Readable::read(r)?;
307 for _ in 0..per_htlc_len {
308 let _txid: Txid = Readable::read(r)?;
309 let htlcs_count: u64 = Readable::read(r)?;
310 for _ in 0..htlcs_count {
311 let _htlc: HTLCOutputInCommitment = Readable::read(r)?;
315 let mut counterparty_delayed_payment_base_key = RequiredWrapper(None);
316 let mut counterparty_htlc_base_key = RequiredWrapper(None);
317 let mut on_counterparty_tx_csv: u16 = 0;
318 read_tlv_fields!(r, {
319 (0, counterparty_delayed_payment_base_key, required),
320 (2, counterparty_htlc_base_key, required),
321 (4, on_counterparty_tx_csv, required),
323 CounterpartyCommitmentParameters {
324 counterparty_delayed_payment_base_key: counterparty_delayed_payment_base_key.0.unwrap(),
325 counterparty_htlc_base_key: counterparty_htlc_base_key.0.unwrap(),
326 on_counterparty_tx_csv,
329 Ok(counterparty_commitment_transaction)
333 /// An entry for an [`OnchainEvent`], stating the block height and hash when the event was
334 /// observed, as well as the transaction causing it.
336 /// Used to determine when the on-chain event can be considered safe from a chain reorganization.
337 #[derive(PartialEq, Eq)]
338 struct OnchainEventEntry {
341 block_hash: Option<BlockHash>, // Added as optional, will be filled in for any entry generated on 0.0.113 or after
343 transaction: Option<Transaction>, // Added as optional, but always filled in, in LDK 0.0.110
346 impl OnchainEventEntry {
347 fn confirmation_threshold(&self) -> u32 {
348 let mut conf_threshold = self.height + ANTI_REORG_DELAY - 1;
350 OnchainEvent::MaturingOutput {
351 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor)
353 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
354 // it's broadcastable when we see the previous block.
355 conf_threshold = cmp::max(conf_threshold, self.height + descriptor.to_self_delay as u32 - 1);
357 OnchainEvent::FundingSpendConfirmation { on_local_output_csv: Some(csv), .. } |
358 OnchainEvent::HTLCSpendConfirmation { on_to_local_output_csv: Some(csv), .. } => {
359 // A CSV'd transaction is confirmable in block (input height) + CSV delay, which means
360 // it's broadcastable when we see the previous block.
361 conf_threshold = cmp::max(conf_threshold, self.height + csv as u32 - 1);
368 fn has_reached_confirmation_threshold(&self, best_block: &BestBlock) -> bool {
369 best_block.height() >= self.confirmation_threshold()
373 /// The (output index, sats value) for the counterparty's output in a commitment transaction.
375 /// This was added as an `Option` in 0.0.110.
376 type CommitmentTxCounterpartyOutputInfo = Option<(u32, u64)>;
378 /// Upon discovering of some classes of onchain tx by ChannelMonitor, we may have to take actions on it
379 /// once they mature to enough confirmations (ANTI_REORG_DELAY)
380 #[derive(PartialEq, Eq)]
382 /// An outbound HTLC failing after a transaction is confirmed. Used
383 /// * when an outbound HTLC output is spent by us after the HTLC timed out
384 /// * an outbound HTLC which was not present in the commitment transaction which appeared
385 /// on-chain (either because it was not fully committed to or it was dust).
386 /// Note that this is *not* used for preimage claims, as those are passed upstream immediately,
387 /// appearing only as an `HTLCSpendConfirmation`, below.
390 payment_hash: PaymentHash,
391 htlc_value_satoshis: Option<u64>,
392 /// None in the second case, above, ie when there is no relevant output in the commitment
393 /// transaction which appeared on chain.
394 commitment_tx_output_idx: Option<u32>,
396 /// An output waiting on [`ANTI_REORG_DELAY`] confirmations before we hand the user the
397 /// [`SpendableOutputDescriptor`].
399 descriptor: SpendableOutputDescriptor,
401 /// A spend of the funding output, either a commitment transaction or a cooperative closing
403 FundingSpendConfirmation {
404 /// The CSV delay for the output of the funding spend transaction (implying it is a local
405 /// commitment transaction, and this is the delay on the to_self output).
406 on_local_output_csv: Option<u16>,
407 /// If the funding spend transaction was a known remote commitment transaction, we track
408 /// the output index and amount of the counterparty's `to_self` output here.
410 /// This allows us to generate a [`Balance::CounterpartyRevokedOutputClaimable`] for the
411 /// counterparty output.
412 commitment_tx_to_counterparty_output: CommitmentTxCounterpartyOutputInfo,
414 /// A spend of a commitment transaction HTLC output, set in the cases where *no* `HTLCUpdate`
415 /// is constructed. This is used when
416 /// * an outbound HTLC is claimed by our counterparty with a preimage, causing us to
417 /// immediately claim the HTLC on the inbound edge and track the resolution here,
418 /// * an inbound HTLC is claimed by our counterparty (with a timeout),
419 /// * an inbound HTLC is claimed by us (with a preimage).
420 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by the revocation
422 /// * a revoked-state HTLC transaction was broadcasted, which was claimed by an
423 /// HTLC-Success/HTLC-Failure transaction (and is still claimable with a revocation
425 HTLCSpendConfirmation {
426 commitment_tx_output_idx: u32,
427 /// If the claim was made by either party with a preimage, this is filled in
428 preimage: Option<PaymentPreimage>,
429 /// If the claim was made by us on an inbound HTLC against a local commitment transaction,
430 /// we set this to the output CSV value which we will have to wait until to spend the
431 /// output (and generate a SpendableOutput event).
432 on_to_local_output_csv: Option<u16>,
436 impl Writeable for OnchainEventEntry {
437 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
438 write_tlv_fields!(writer, {
439 (0, self.txid, required),
440 (1, self.transaction, option),
441 (2, self.height, required),
442 (3, self.block_hash, option),
443 (4, self.event, required),
449 impl MaybeReadable for OnchainEventEntry {
450 fn read<R: io::Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
451 let mut txid = Txid::all_zeros();
452 let mut transaction = None;
453 let mut block_hash = None;
455 let mut event = UpgradableRequired(None);
456 read_tlv_fields!(reader, {
458 (1, transaction, option),
459 (2, height, required),
460 (3, block_hash, option),
461 (4, event, upgradable_required),
463 Ok(Some(Self { txid, transaction, height, block_hash, event: _init_tlv_based_struct_field!(event, upgradable_required) }))
467 impl_writeable_tlv_based_enum_upgradable!(OnchainEvent,
469 (0, source, required),
470 (1, htlc_value_satoshis, option),
471 (2, payment_hash, required),
472 (3, commitment_tx_output_idx, option),
474 (1, MaturingOutput) => {
475 (0, descriptor, required),
477 (3, FundingSpendConfirmation) => {
478 (0, on_local_output_csv, option),
479 (1, commitment_tx_to_counterparty_output, option),
481 (5, HTLCSpendConfirmation) => {
482 (0, commitment_tx_output_idx, required),
483 (2, preimage, option),
484 (4, on_to_local_output_csv, option),
489 #[derive(Clone, PartialEq, Eq)]
490 pub(crate) enum ChannelMonitorUpdateStep {
491 LatestHolderCommitmentTXInfo {
492 commitment_tx: HolderCommitmentTransaction,
493 /// Note that LDK after 0.0.115 supports this only containing dust HTLCs (implying the
494 /// `Signature` field is never filled in). At that point, non-dust HTLCs are implied by the
495 /// HTLC fields in `commitment_tx` and the sources passed via `nondust_htlc_sources`.
496 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
497 claimed_htlcs: Vec<(SentHTLCId, PaymentPreimage)>,
498 nondust_htlc_sources: Vec<HTLCSource>,
500 LatestCounterpartyCommitmentTXInfo {
501 commitment_txid: Txid,
502 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
503 commitment_number: u64,
504 their_per_commitment_point: PublicKey,
507 payment_preimage: PaymentPreimage,
513 /// Used to indicate that the no future updates will occur, and likely that the latest holder
514 /// commitment transaction(s) should be broadcast, as the channel has been force-closed.
516 /// If set to false, we shouldn't broadcast the latest holder commitment transaction as we
517 /// think we've fallen behind!
518 should_broadcast: bool,
521 scriptpubkey: Script,
525 impl ChannelMonitorUpdateStep {
526 fn variant_name(&self) -> &'static str {
528 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { .. } => "LatestHolderCommitmentTXInfo",
529 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } => "LatestCounterpartyCommitmentTXInfo",
530 ChannelMonitorUpdateStep::PaymentPreimage { .. } => "PaymentPreimage",
531 ChannelMonitorUpdateStep::CommitmentSecret { .. } => "CommitmentSecret",
532 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => "ChannelForceClosed",
533 ChannelMonitorUpdateStep::ShutdownScript { .. } => "ShutdownScript",
538 impl_writeable_tlv_based_enum_upgradable!(ChannelMonitorUpdateStep,
539 (0, LatestHolderCommitmentTXInfo) => {
540 (0, commitment_tx, required),
541 (1, claimed_htlcs, optional_vec),
542 (2, htlc_outputs, required_vec),
543 (4, nondust_htlc_sources, optional_vec),
545 (1, LatestCounterpartyCommitmentTXInfo) => {
546 (0, commitment_txid, required),
547 (2, commitment_number, required),
548 (4, their_per_commitment_point, required),
549 (6, htlc_outputs, required_vec),
551 (2, PaymentPreimage) => {
552 (0, payment_preimage, required),
554 (3, CommitmentSecret) => {
556 (2, secret, required),
558 (4, ChannelForceClosed) => {
559 (0, should_broadcast, required),
561 (5, ShutdownScript) => {
562 (0, scriptpubkey, required),
566 /// Details about the balance(s) available for spending once the channel appears on chain.
568 /// See [`ChannelMonitor::get_claimable_balances`] for more details on when these will or will not
570 #[derive(Clone, Debug, PartialEq, Eq)]
571 #[cfg_attr(test, derive(PartialOrd, Ord))]
573 /// The channel is not yet closed (or the commitment or closing transaction has not yet
574 /// appeared in a block). The given balance is claimable (less on-chain fees) if the channel is
575 /// force-closed now.
576 ClaimableOnChannelClose {
577 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
578 /// required to do so.
579 claimable_amount_satoshis: u64,
581 /// The channel has been closed, and the given balance is ours but awaiting confirmations until
582 /// we consider it spendable.
583 ClaimableAwaitingConfirmations {
584 /// The amount available to claim, in satoshis, possibly excluding the on-chain fees which
585 /// were spent in broadcasting the transaction.
586 claimable_amount_satoshis: u64,
587 /// The height at which an [`Event::SpendableOutputs`] event will be generated for this
589 confirmation_height: u32,
591 /// The channel has been closed, and the given balance should be ours but awaiting spending
592 /// transaction confirmation. If the spending transaction does not confirm in time, it is
593 /// possible our counterparty can take the funds by broadcasting an HTLC timeout on-chain.
595 /// Once the spending transaction confirms, before it has reached enough confirmations to be
596 /// considered safe from chain reorganizations, the balance will instead be provided via
597 /// [`Balance::ClaimableAwaitingConfirmations`].
598 ContentiousClaimable {
599 /// The amount available to claim, in satoshis, excluding the on-chain fees which will be
600 /// required to do so.
601 claimable_amount_satoshis: u64,
602 /// The height at which the counterparty may be able to claim the balance if we have not
605 /// The payment hash that locks this HTLC.
606 payment_hash: PaymentHash,
607 /// The preimage that can be used to claim this HTLC.
608 payment_preimage: PaymentPreimage,
610 /// HTLCs which we sent to our counterparty which are claimable after a timeout (less on-chain
611 /// fees) if the counterparty does not know the preimage for the HTLCs. These are somewhat
612 /// likely to be claimed by our counterparty before we do.
613 MaybeTimeoutClaimableHTLC {
614 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
615 /// which will be required to do so.
616 claimable_amount_satoshis: u64,
617 /// The height at which we will be able to claim the balance if our counterparty has not
619 claimable_height: u32,
620 /// The payment hash whose preimage our counterparty needs to claim this HTLC.
621 payment_hash: PaymentHash,
623 /// HTLCs which we received from our counterparty which are claimable with a preimage which we
624 /// do not currently have. This will only be claimable if we receive the preimage from the node
625 /// to which we forwarded this HTLC before the timeout.
626 MaybePreimageClaimableHTLC {
627 /// The amount potentially available to claim, in satoshis, excluding the on-chain fees
628 /// which will be required to do so.
629 claimable_amount_satoshis: u64,
630 /// The height at which our counterparty will be able to claim the balance if we have not
631 /// yet received the preimage and claimed it ourselves.
633 /// The payment hash whose preimage we need to claim this HTLC.
634 payment_hash: PaymentHash,
636 /// The channel has been closed, and our counterparty broadcasted a revoked commitment
639 /// Thus, we're able to claim all outputs in the commitment transaction, one of which has the
640 /// following amount.
641 CounterpartyRevokedOutputClaimable {
642 /// The amount, in satoshis, of the output which we can claim.
644 /// Note that for outputs from HTLC balances this may be excluding some on-chain fees that
645 /// were already spent.
646 claimable_amount_satoshis: u64,
651 /// The amount claimable, in satoshis. This excludes balances that we are unsure if we are able
652 /// to claim, this is because we are waiting for a preimage or for a timeout to expire. For more
653 /// information on these balances see [`Balance::MaybeTimeoutClaimableHTLC`] and
654 /// [`Balance::MaybePreimageClaimableHTLC`].
656 /// On-chain fees required to claim the balance are not included in this amount.
657 pub fn claimable_amount_satoshis(&self) -> u64 {
659 Balance::ClaimableOnChannelClose {
660 claimable_amount_satoshis,
661 } => *claimable_amount_satoshis,
662 Balance::ClaimableAwaitingConfirmations {
663 claimable_amount_satoshis,
665 } => *claimable_amount_satoshis,
666 Balance::ContentiousClaimable {
667 claimable_amount_satoshis,
669 } => *claimable_amount_satoshis,
670 Balance::MaybeTimeoutClaimableHTLC {
673 Balance::MaybePreimageClaimableHTLC {
676 Balance::CounterpartyRevokedOutputClaimable {
677 claimable_amount_satoshis,
679 } => *claimable_amount_satoshis,
684 /// An HTLC which has been irrevocably resolved on-chain, and has reached ANTI_REORG_DELAY.
685 #[derive(PartialEq, Eq)]
686 struct IrrevocablyResolvedHTLC {
687 commitment_tx_output_idx: Option<u32>,
688 /// The txid of the transaction which resolved the HTLC, this may be a commitment (if the HTLC
689 /// was not present in the confirmed commitment transaction), HTLC-Success, or HTLC-Timeout
691 resolving_txid: Option<Txid>, // Added as optional, but always filled in, in 0.0.110
692 resolving_tx: Option<Transaction>,
693 /// Only set if the HTLC claim was ours using a payment preimage
694 payment_preimage: Option<PaymentPreimage>,
697 // In LDK versions prior to 0.0.111 commitment_tx_output_idx was not Option-al and
698 // IrrevocablyResolvedHTLC objects only existed for non-dust HTLCs. This was a bug, but to maintain
699 // backwards compatibility we must ensure we always write out a commitment_tx_output_idx field,
700 // using `u32::max_value()` as a sentinal to indicate the HTLC was dust.
701 impl Writeable for IrrevocablyResolvedHTLC {
702 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), io::Error> {
703 let mapped_commitment_tx_output_idx = self.commitment_tx_output_idx.unwrap_or(u32::max_value());
704 write_tlv_fields!(writer, {
705 (0, mapped_commitment_tx_output_idx, required),
706 (1, self.resolving_txid, option),
707 (2, self.payment_preimage, option),
708 (3, self.resolving_tx, option),
714 impl Readable for IrrevocablyResolvedHTLC {
715 fn read<R: io::Read>(reader: &mut R) -> Result<Self, DecodeError> {
716 let mut mapped_commitment_tx_output_idx = 0;
717 let mut resolving_txid = None;
718 let mut payment_preimage = None;
719 let mut resolving_tx = None;
720 read_tlv_fields!(reader, {
721 (0, mapped_commitment_tx_output_idx, required),
722 (1, resolving_txid, option),
723 (2, payment_preimage, option),
724 (3, resolving_tx, option),
727 commitment_tx_output_idx: if mapped_commitment_tx_output_idx == u32::max_value() { None } else { Some(mapped_commitment_tx_output_idx) },
735 /// A ChannelMonitor handles chain events (blocks connected and disconnected) and generates
736 /// on-chain transactions to ensure no loss of funds occurs.
738 /// You MUST ensure that no ChannelMonitors for a given channel anywhere contain out-of-date
739 /// information and are actively monitoring the chain.
741 /// Pending Events or updated HTLCs which have not yet been read out by
742 /// get_and_clear_pending_monitor_events or get_and_clear_pending_events are serialized to disk and
743 /// reloaded at deserialize-time. Thus, you must ensure that, when handling events, all events
744 /// gotten are fully handled before re-serializing the new state.
746 /// Note that the deserializer is only implemented for (BlockHash, ChannelMonitor), which
747 /// tells you the last block hash which was block_connect()ed. You MUST rescan any blocks along
748 /// the "reorg path" (ie disconnecting blocks until you find a common ancestor from both the
749 /// returned block hash and the the current chain and then reconnecting blocks to get to the
750 /// best chain) upon deserializing the object!
751 pub struct ChannelMonitor<Signer: WriteableEcdsaChannelSigner> {
753 pub(crate) inner: Mutex<ChannelMonitorImpl<Signer>>,
755 inner: Mutex<ChannelMonitorImpl<Signer>>,
759 pub(crate) struct ChannelMonitorImpl<Signer: WriteableEcdsaChannelSigner> {
760 latest_update_id: u64,
761 commitment_transaction_number_obscure_factor: u64,
763 destination_script: Script,
764 broadcasted_holder_revokable_script: Option<(Script, PublicKey, PublicKey)>,
765 counterparty_payment_script: Script,
766 shutdown_script: Option<Script>,
768 channel_keys_id: [u8; 32],
769 holder_revocation_basepoint: PublicKey,
770 funding_info: (OutPoint, Script),
771 current_counterparty_commitment_txid: Option<Txid>,
772 prev_counterparty_commitment_txid: Option<Txid>,
774 counterparty_commitment_params: CounterpartyCommitmentParameters,
775 funding_redeemscript: Script,
776 channel_value_satoshis: u64,
777 // first is the idx of the first of the two per-commitment points
778 their_cur_per_commitment_points: Option<(u64, PublicKey, Option<PublicKey>)>,
780 on_holder_tx_csv: u16,
782 commitment_secrets: CounterpartyCommitmentSecrets,
783 /// The set of outpoints in each counterparty commitment transaction. We always need at least
784 /// the payment hash from `HTLCOutputInCommitment` to claim even a revoked commitment
785 /// transaction broadcast as we need to be able to construct the witness script in all cases.
786 counterparty_claimable_outpoints: HashMap<Txid, Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>>,
787 /// We cannot identify HTLC-Success or HTLC-Timeout transactions by themselves on the chain.
788 /// Nor can we figure out their commitment numbers without the commitment transaction they are
789 /// spending. Thus, in order to claim them via revocation key, we track all the counterparty
790 /// commitment transactions which we find on-chain, mapping them to the commitment number which
791 /// can be used to derive the revocation key and claim the transactions.
792 counterparty_commitment_txn_on_chain: HashMap<Txid, u64>,
793 /// Cache used to make pruning of payment_preimages faster.
794 /// Maps payment_hash values to commitment numbers for counterparty transactions for non-revoked
795 /// counterparty transactions (ie should remain pretty small).
796 /// Serialized to disk but should generally not be sent to Watchtowers.
797 counterparty_hash_commitment_number: HashMap<PaymentHash, u64>,
799 counterparty_fulfilled_htlcs: HashMap<SentHTLCId, PaymentPreimage>,
801 // We store two holder commitment transactions to avoid any race conditions where we may update
802 // some monitors (potentially on watchtowers) but then fail to update others, resulting in the
803 // various monitors for one channel being out of sync, and us broadcasting a holder
804 // transaction for which we have deleted claim information on some watchtowers.
805 prev_holder_signed_commitment_tx: Option<HolderSignedTx>,
806 current_holder_commitment_tx: HolderSignedTx,
808 // Used just for ChannelManager to make sure it has the latest channel data during
810 current_counterparty_commitment_number: u64,
811 // Used just for ChannelManager to make sure it has the latest channel data during
813 current_holder_commitment_number: u64,
815 /// The set of payment hashes from inbound payments for which we know the preimage. Payment
816 /// preimages that are not included in any unrevoked local commitment transaction or unrevoked
817 /// remote commitment transactions are automatically removed when commitment transactions are
819 payment_preimages: HashMap<PaymentHash, PaymentPreimage>,
821 // Note that `MonitorEvent`s MUST NOT be generated during update processing, only generated
822 // during chain data processing. This prevents a race in `ChainMonitor::update_channel` (and
823 // presumably user implementations thereof as well) where we update the in-memory channel
824 // object, then before the persistence finishes (as it's all under a read-lock), we return
825 // pending events to the user or to the relevant `ChannelManager`. Then, on reload, we'll have
826 // the pre-event state here, but have processed the event in the `ChannelManager`.
827 // Note that because the `event_lock` in `ChainMonitor` is only taken in
828 // block/transaction-connected events and *not* during block/transaction-disconnected events,
829 // we further MUST NOT generate events during block/transaction-disconnection.
830 pending_monitor_events: Vec<MonitorEvent>,
832 pending_events: Vec<Event>,
834 // Used to track on-chain events (i.e., transactions part of channels confirmed on chain) on
835 // which to take actions once they reach enough confirmations. Each entry includes the
836 // transaction's id and the height when the transaction was confirmed on chain.
837 onchain_events_awaiting_threshold_conf: Vec<OnchainEventEntry>,
839 // If we get serialized out and re-read, we need to make sure that the chain monitoring
840 // interface knows about the TXOs that we want to be notified of spends of. We could probably
841 // be smart and derive them from the above storage fields, but its much simpler and more
842 // Obviously Correct (tm) if we just keep track of them explicitly.
843 outputs_to_watch: HashMap<Txid, Vec<(u32, Script)>>,
846 pub onchain_tx_handler: OnchainTxHandler<Signer>,
848 onchain_tx_handler: OnchainTxHandler<Signer>,
850 // This is set when the Channel[Manager] generated a ChannelMonitorUpdate which indicated the
851 // channel has been force-closed. After this is set, no further holder commitment transaction
852 // updates may occur, and we panic!() if one is provided.
853 lockdown_from_offchain: bool,
855 // Set once we've signed a holder commitment transaction and handed it over to our
856 // OnchainTxHandler. After this is set, no future updates to our holder commitment transactions
857 // may occur, and we fail any such monitor updates.
859 // In case of update rejection due to a locally already signed commitment transaction, we
860 // nevertheless store update content to track in case of concurrent broadcast by another
861 // remote monitor out-of-order with regards to the block view.
862 holder_tx_signed: bool,
864 // If a spend of the funding output is seen, we set this to true and reject any further
865 // updates. This prevents any further changes in the offchain state no matter the order
866 // of block connection between ChannelMonitors and the ChannelManager.
867 funding_spend_seen: bool,
869 /// Set to `Some` of the confirmed transaction spending the funding input of the channel after
870 /// reaching `ANTI_REORG_DELAY` confirmations.
871 funding_spend_confirmed: Option<Txid>,
873 confirmed_commitment_tx_counterparty_output: CommitmentTxCounterpartyOutputInfo,
874 /// The set of HTLCs which have been either claimed or failed on chain and have reached
875 /// the requisite confirmations on the claim/fail transaction (either ANTI_REORG_DELAY or the
876 /// spending CSV for revocable outputs).
877 htlcs_resolved_on_chain: Vec<IrrevocablyResolvedHTLC>,
879 /// The set of `SpendableOutput` events which we have already passed upstream to be claimed.
880 /// These are tracked explicitly to ensure that we don't generate the same events redundantly
881 /// if users duplicatively confirm old transactions. Specifically for transactions claiming a
882 /// revoked remote outpoint we otherwise have no tracking at all once they've reached
883 /// [`ANTI_REORG_DELAY`], so we have to track them here.
884 spendable_txids_confirmed: Vec<Txid>,
886 // We simply modify best_block in Channel's block_connected so that serialization is
887 // consistent but hopefully the users' copy handles block_connected in a consistent way.
888 // (we do *not*, however, update them in update_monitor to ensure any local user copies keep
889 // their best_block from its state and not based on updated copies that didn't run through
890 // the full block_connected).
891 best_block: BestBlock,
893 /// The node_id of our counterparty
894 counterparty_node_id: Option<PublicKey>,
897 /// Transaction outputs to watch for on-chain spends.
898 pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
900 impl<Signer: WriteableEcdsaChannelSigner> PartialEq for ChannelMonitor<Signer> where Signer: PartialEq {
901 fn eq(&self, other: &Self) -> bool {
902 // We need some kind of total lockorder. Absent a better idea, we sort by position in
903 // memory and take locks in that order (assuming that we can't move within memory while a
905 let ord = ((self as *const _) as usize) < ((other as *const _) as usize);
906 let a = if ord { self.inner.unsafe_well_ordered_double_lock_self() } else { other.inner.unsafe_well_ordered_double_lock_self() };
907 let b = if ord { other.inner.unsafe_well_ordered_double_lock_self() } else { self.inner.unsafe_well_ordered_double_lock_self() };
912 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitor<Signer> {
913 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
914 self.inner.lock().unwrap().write(writer)
918 // These are also used for ChannelMonitorUpdate, above.
919 const SERIALIZATION_VERSION: u8 = 1;
920 const MIN_SERIALIZATION_VERSION: u8 = 1;
922 impl<Signer: WriteableEcdsaChannelSigner> Writeable for ChannelMonitorImpl<Signer> {
923 fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error> {
924 write_ver_prefix!(writer, SERIALIZATION_VERSION, MIN_SERIALIZATION_VERSION);
926 self.latest_update_id.write(writer)?;
928 // Set in initial Channel-object creation, so should always be set by now:
929 U48(self.commitment_transaction_number_obscure_factor).write(writer)?;
931 self.destination_script.write(writer)?;
932 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
933 writer.write_all(&[0; 1])?;
934 broadcasted_holder_revokable_script.0.write(writer)?;
935 broadcasted_holder_revokable_script.1.write(writer)?;
936 broadcasted_holder_revokable_script.2.write(writer)?;
938 writer.write_all(&[1; 1])?;
941 self.counterparty_payment_script.write(writer)?;
942 match &self.shutdown_script {
943 Some(script) => script.write(writer)?,
944 None => Script::new().write(writer)?,
947 self.channel_keys_id.write(writer)?;
948 self.holder_revocation_basepoint.write(writer)?;
949 writer.write_all(&self.funding_info.0.txid[..])?;
950 writer.write_all(&self.funding_info.0.index.to_be_bytes())?;
951 self.funding_info.1.write(writer)?;
952 self.current_counterparty_commitment_txid.write(writer)?;
953 self.prev_counterparty_commitment_txid.write(writer)?;
955 self.counterparty_commitment_params.write(writer)?;
956 self.funding_redeemscript.write(writer)?;
957 self.channel_value_satoshis.write(writer)?;
959 match self.their_cur_per_commitment_points {
960 Some((idx, pubkey, second_option)) => {
961 writer.write_all(&byte_utils::be48_to_array(idx))?;
962 writer.write_all(&pubkey.serialize())?;
963 match second_option {
964 Some(second_pubkey) => {
965 writer.write_all(&second_pubkey.serialize())?;
968 writer.write_all(&[0; 33])?;
973 writer.write_all(&byte_utils::be48_to_array(0))?;
977 writer.write_all(&self.on_holder_tx_csv.to_be_bytes())?;
979 self.commitment_secrets.write(writer)?;
981 macro_rules! serialize_htlc_in_commitment {
982 ($htlc_output: expr) => {
983 writer.write_all(&[$htlc_output.offered as u8; 1])?;
984 writer.write_all(&$htlc_output.amount_msat.to_be_bytes())?;
985 writer.write_all(&$htlc_output.cltv_expiry.to_be_bytes())?;
986 writer.write_all(&$htlc_output.payment_hash.0[..])?;
987 $htlc_output.transaction_output_index.write(writer)?;
991 writer.write_all(&(self.counterparty_claimable_outpoints.len() as u64).to_be_bytes())?;
992 for (ref txid, ref htlc_infos) in self.counterparty_claimable_outpoints.iter() {
993 writer.write_all(&txid[..])?;
994 writer.write_all(&(htlc_infos.len() as u64).to_be_bytes())?;
995 for &(ref htlc_output, ref htlc_source) in htlc_infos.iter() {
996 debug_assert!(htlc_source.is_none() || Some(**txid) == self.current_counterparty_commitment_txid
997 || Some(**txid) == self.prev_counterparty_commitment_txid,
998 "HTLC Sources for all revoked commitment transactions should be none!");
999 serialize_htlc_in_commitment!(htlc_output);
1000 htlc_source.as_ref().map(|b| b.as_ref()).write(writer)?;
1004 writer.write_all(&(self.counterparty_commitment_txn_on_chain.len() as u64).to_be_bytes())?;
1005 for (ref txid, commitment_number) in self.counterparty_commitment_txn_on_chain.iter() {
1006 writer.write_all(&txid[..])?;
1007 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1010 writer.write_all(&(self.counterparty_hash_commitment_number.len() as u64).to_be_bytes())?;
1011 for (ref payment_hash, commitment_number) in self.counterparty_hash_commitment_number.iter() {
1012 writer.write_all(&payment_hash.0[..])?;
1013 writer.write_all(&byte_utils::be48_to_array(*commitment_number))?;
1016 if let Some(ref prev_holder_tx) = self.prev_holder_signed_commitment_tx {
1017 writer.write_all(&[1; 1])?;
1018 prev_holder_tx.write(writer)?;
1020 writer.write_all(&[0; 1])?;
1023 self.current_holder_commitment_tx.write(writer)?;
1025 writer.write_all(&byte_utils::be48_to_array(self.current_counterparty_commitment_number))?;
1026 writer.write_all(&byte_utils::be48_to_array(self.current_holder_commitment_number))?;
1028 writer.write_all(&(self.payment_preimages.len() as u64).to_be_bytes())?;
1029 for payment_preimage in self.payment_preimages.values() {
1030 writer.write_all(&payment_preimage.0[..])?;
1033 writer.write_all(&(self.pending_monitor_events.iter().filter(|ev| match ev {
1034 MonitorEvent::HTLCEvent(_) => true,
1035 MonitorEvent::CommitmentTxConfirmed(_) => true,
1037 }).count() as u64).to_be_bytes())?;
1038 for event in self.pending_monitor_events.iter() {
1040 MonitorEvent::HTLCEvent(upd) => {
1044 MonitorEvent::CommitmentTxConfirmed(_) => 1u8.write(writer)?,
1045 _ => {}, // Covered in the TLV writes below
1049 writer.write_all(&(self.pending_events.len() as u64).to_be_bytes())?;
1050 for event in self.pending_events.iter() {
1051 event.write(writer)?;
1054 self.best_block.block_hash().write(writer)?;
1055 writer.write_all(&self.best_block.height().to_be_bytes())?;
1057 writer.write_all(&(self.onchain_events_awaiting_threshold_conf.len() as u64).to_be_bytes())?;
1058 for ref entry in self.onchain_events_awaiting_threshold_conf.iter() {
1059 entry.write(writer)?;
1062 (self.outputs_to_watch.len() as u64).write(writer)?;
1063 for (txid, idx_scripts) in self.outputs_to_watch.iter() {
1064 txid.write(writer)?;
1065 (idx_scripts.len() as u64).write(writer)?;
1066 for (idx, script) in idx_scripts.iter() {
1068 script.write(writer)?;
1071 self.onchain_tx_handler.write(writer)?;
1073 self.lockdown_from_offchain.write(writer)?;
1074 self.holder_tx_signed.write(writer)?;
1076 write_tlv_fields!(writer, {
1077 (1, self.funding_spend_confirmed, option),
1078 (3, self.htlcs_resolved_on_chain, required_vec),
1079 (5, self.pending_monitor_events, required_vec),
1080 (7, self.funding_spend_seen, required),
1081 (9, self.counterparty_node_id, option),
1082 (11, self.confirmed_commitment_tx_counterparty_output, option),
1083 (13, self.spendable_txids_confirmed, required_vec),
1084 (15, self.counterparty_fulfilled_htlcs, required),
1091 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1092 /// For lockorder enforcement purposes, we need to have a single site which constructs the
1093 /// `inner` mutex, otherwise cases where we lock two monitors at the same time (eg in our
1094 /// PartialEq implementation) we may decide a lockorder violation has occurred.
1095 fn from_impl(imp: ChannelMonitorImpl<Signer>) -> Self {
1096 ChannelMonitor { inner: Mutex::new(imp) }
1099 pub(crate) fn new(secp_ctx: Secp256k1<secp256k1::All>, keys: Signer, shutdown_script: Option<Script>,
1100 on_counterparty_tx_csv: u16, destination_script: &Script, funding_info: (OutPoint, Script),
1101 channel_parameters: &ChannelTransactionParameters,
1102 funding_redeemscript: Script, channel_value_satoshis: u64,
1103 commitment_transaction_number_obscure_factor: u64,
1104 initial_holder_commitment_tx: HolderCommitmentTransaction,
1105 best_block: BestBlock, counterparty_node_id: PublicKey) -> ChannelMonitor<Signer> {
1107 assert!(commitment_transaction_number_obscure_factor <= (1 << 48));
1108 let payment_key_hash = WPubkeyHash::hash(&keys.pubkeys().payment_point.serialize());
1109 let counterparty_payment_script = Builder::new().push_opcode(opcodes::all::OP_PUSHBYTES_0).push_slice(&payment_key_hash[..]).into_script();
1111 let counterparty_channel_parameters = channel_parameters.counterparty_parameters.as_ref().unwrap();
1112 let counterparty_delayed_payment_base_key = counterparty_channel_parameters.pubkeys.delayed_payment_basepoint;
1113 let counterparty_htlc_base_key = counterparty_channel_parameters.pubkeys.htlc_basepoint;
1114 let counterparty_commitment_params = CounterpartyCommitmentParameters { counterparty_delayed_payment_base_key, counterparty_htlc_base_key, on_counterparty_tx_csv };
1116 let channel_keys_id = keys.channel_keys_id();
1117 let holder_revocation_basepoint = keys.pubkeys().revocation_basepoint;
1119 // block for Rust 1.34 compat
1120 let (holder_commitment_tx, current_holder_commitment_number) = {
1121 let trusted_tx = initial_holder_commitment_tx.trust();
1122 let txid = trusted_tx.txid();
1124 let tx_keys = trusted_tx.keys();
1125 let holder_commitment_tx = HolderSignedTx {
1127 revocation_key: tx_keys.revocation_key,
1128 a_htlc_key: tx_keys.broadcaster_htlc_key,
1129 b_htlc_key: tx_keys.countersignatory_htlc_key,
1130 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
1131 per_commitment_point: tx_keys.per_commitment_point,
1132 htlc_outputs: Vec::new(), // There are never any HTLCs in the initial commitment transactions
1133 to_self_value_sat: initial_holder_commitment_tx.to_broadcaster_value_sat(),
1134 feerate_per_kw: trusted_tx.feerate_per_kw(),
1136 (holder_commitment_tx, trusted_tx.commitment_number())
1139 let onchain_tx_handler =
1140 OnchainTxHandler::new(destination_script.clone(), keys,
1141 channel_parameters.clone(), initial_holder_commitment_tx, secp_ctx);
1143 let mut outputs_to_watch = HashMap::new();
1144 outputs_to_watch.insert(funding_info.0.txid, vec![(funding_info.0.index as u32, funding_info.1.clone())]);
1146 Self::from_impl(ChannelMonitorImpl {
1147 latest_update_id: 0,
1148 commitment_transaction_number_obscure_factor,
1150 destination_script: destination_script.clone(),
1151 broadcasted_holder_revokable_script: None,
1152 counterparty_payment_script,
1156 holder_revocation_basepoint,
1158 current_counterparty_commitment_txid: None,
1159 prev_counterparty_commitment_txid: None,
1161 counterparty_commitment_params,
1162 funding_redeemscript,
1163 channel_value_satoshis,
1164 their_cur_per_commitment_points: None,
1166 on_holder_tx_csv: counterparty_channel_parameters.selected_contest_delay,
1168 commitment_secrets: CounterpartyCommitmentSecrets::new(),
1169 counterparty_claimable_outpoints: HashMap::new(),
1170 counterparty_commitment_txn_on_chain: HashMap::new(),
1171 counterparty_hash_commitment_number: HashMap::new(),
1172 counterparty_fulfilled_htlcs: HashMap::new(),
1174 prev_holder_signed_commitment_tx: None,
1175 current_holder_commitment_tx: holder_commitment_tx,
1176 current_counterparty_commitment_number: 1 << 48,
1177 current_holder_commitment_number,
1179 payment_preimages: HashMap::new(),
1180 pending_monitor_events: Vec::new(),
1181 pending_events: Vec::new(),
1183 onchain_events_awaiting_threshold_conf: Vec::new(),
1188 lockdown_from_offchain: false,
1189 holder_tx_signed: false,
1190 funding_spend_seen: false,
1191 funding_spend_confirmed: None,
1192 confirmed_commitment_tx_counterparty_output: None,
1193 htlcs_resolved_on_chain: Vec::new(),
1194 spendable_txids_confirmed: Vec::new(),
1197 counterparty_node_id: Some(counterparty_node_id),
1202 fn provide_secret(&self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
1203 self.inner.lock().unwrap().provide_secret(idx, secret)
1206 /// Informs this monitor of the latest counterparty (ie non-broadcastable) commitment transaction.
1207 /// The monitor watches for it to be broadcasted and then uses the HTLC information (and
1208 /// possibly future revocation/preimage information) to claim outputs where possible.
1209 /// We cache also the mapping hash:commitment number to lighten pruning of old preimages by watchtowers.
1210 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(
1213 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>,
1214 commitment_number: u64,
1215 their_per_commitment_point: PublicKey,
1217 ) where L::Target: Logger {
1218 self.inner.lock().unwrap().provide_latest_counterparty_commitment_tx(
1219 txid, htlc_outputs, commitment_number, their_per_commitment_point, logger)
1223 fn provide_latest_holder_commitment_tx(
1224 &self, holder_commitment_tx: HolderCommitmentTransaction,
1225 htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>,
1226 ) -> Result<(), ()> {
1227 self.inner.lock().unwrap().provide_latest_holder_commitment_tx(holder_commitment_tx, htlc_outputs, &Vec::new(), Vec::new()).map_err(|_| ())
1230 /// This is used to provide payment preimage(s) out-of-band during startup without updating the
1231 /// off-chain state with a new commitment transaction.
1232 pub(crate) fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
1234 payment_hash: &PaymentHash,
1235 payment_preimage: &PaymentPreimage,
1237 fee_estimator: &LowerBoundedFeeEstimator<F>,
1240 B::Target: BroadcasterInterface,
1241 F::Target: FeeEstimator,
1244 self.inner.lock().unwrap().provide_payment_preimage(
1245 payment_hash, payment_preimage, broadcaster, fee_estimator, logger)
1248 /// Updates a ChannelMonitor on the basis of some new information provided by the Channel
1251 /// panics if the given update is not the next update by update_id.
1252 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(
1254 updates: &ChannelMonitorUpdate,
1260 B::Target: BroadcasterInterface,
1261 F::Target: FeeEstimator,
1264 self.inner.lock().unwrap().update_monitor(updates, broadcaster, fee_estimator, logger)
1267 /// Gets the update_id from the latest ChannelMonitorUpdate which was applied to this
1269 pub fn get_latest_update_id(&self) -> u64 {
1270 self.inner.lock().unwrap().get_latest_update_id()
1273 /// Gets the funding transaction outpoint of the channel this ChannelMonitor is monitoring for.
1274 pub fn get_funding_txo(&self) -> (OutPoint, Script) {
1275 self.inner.lock().unwrap().get_funding_txo().clone()
1278 /// Gets a list of txids, with their output scripts (in the order they appear in the
1279 /// transaction), which we must learn about spends of via block_connected().
1280 pub fn get_outputs_to_watch(&self) -> Vec<(Txid, Vec<(u32, Script)>)> {
1281 self.inner.lock().unwrap().get_outputs_to_watch()
1282 .iter().map(|(txid, outputs)| (*txid, outputs.clone())).collect()
1285 /// Loads the funding txo and outputs to watch into the given `chain::Filter` by repeatedly
1286 /// calling `chain::Filter::register_output` and `chain::Filter::register_tx` until all outputs
1287 /// have been registered.
1288 pub fn load_outputs_to_watch<F: Deref>(&self, filter: &F) where F::Target: chain::Filter {
1289 let lock = self.inner.lock().unwrap();
1290 filter.register_tx(&lock.get_funding_txo().0.txid, &lock.get_funding_txo().1);
1291 for (txid, outputs) in lock.get_outputs_to_watch().iter() {
1292 for (index, script_pubkey) in outputs.iter() {
1293 assert!(*index <= u16::max_value() as u32);
1294 filter.register_output(WatchedOutput {
1296 outpoint: OutPoint { txid: *txid, index: *index as u16 },
1297 script_pubkey: script_pubkey.clone(),
1303 /// Get the list of HTLCs who's status has been updated on chain. This should be called by
1304 /// ChannelManager via [`chain::Watch::release_pending_monitor_events`].
1305 pub fn get_and_clear_pending_monitor_events(&self) -> Vec<MonitorEvent> {
1306 self.inner.lock().unwrap().get_and_clear_pending_monitor_events()
1309 /// Gets the list of pending events which were generated by previous actions, clearing the list
1312 /// This is called by the [`EventsProvider::process_pending_events`] implementation for
1313 /// [`ChainMonitor`].
1315 /// [`EventsProvider::process_pending_events`]: crate::events::EventsProvider::process_pending_events
1316 /// [`ChainMonitor`]: crate::chain::chainmonitor::ChainMonitor
1317 pub fn get_and_clear_pending_events(&self) -> Vec<Event> {
1318 self.inner.lock().unwrap().get_and_clear_pending_events()
1321 pub(crate) fn get_min_seen_secret(&self) -> u64 {
1322 self.inner.lock().unwrap().get_min_seen_secret()
1325 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
1326 self.inner.lock().unwrap().get_cur_counterparty_commitment_number()
1329 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
1330 self.inner.lock().unwrap().get_cur_holder_commitment_number()
1333 /// Gets the `node_id` of the counterparty for this channel.
1335 /// Will be `None` for channels constructed on LDK versions prior to 0.0.110 and always `Some`
1337 pub fn get_counterparty_node_id(&self) -> Option<PublicKey> {
1338 self.inner.lock().unwrap().counterparty_node_id
1341 /// Used by ChannelManager deserialization to broadcast the latest holder state if its copy of
1342 /// the Channel was out-of-date.
1344 /// You may also use this to broadcast the latest local commitment transaction, either because
1345 /// a monitor update failed with [`ChannelMonitorUpdateStatus::PermanentFailure`] or because we've
1346 /// fallen behind (i.e. we've received proof that our counterparty side knows a revocation
1347 /// secret we gave them that they shouldn't know).
1349 /// Broadcasting these transactions in the second case is UNSAFE, as they allow counterparty
1350 /// side to punish you. Nevertheless you may want to broadcast them if counterparty doesn't
1351 /// close channel with their commitment transaction after a substantial amount of time. Best
1352 /// may be to contact the other node operator out-of-band to coordinate other options available
1353 /// to you. In any-case, the choice is up to you.
1355 /// [`ChannelMonitorUpdateStatus::PermanentFailure`]: super::ChannelMonitorUpdateStatus::PermanentFailure
1356 pub fn get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1357 where L::Target: Logger {
1358 self.inner.lock().unwrap().get_latest_holder_commitment_txn(logger)
1361 /// Unsafe test-only version of get_latest_holder_commitment_txn used by our test framework
1362 /// to bypass HolderCommitmentTransaction state update lockdown after signature and generate
1363 /// revoked commitment transaction.
1364 #[cfg(any(test, feature = "unsafe_revoked_tx_signing"))]
1365 pub fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&self, logger: &L) -> Vec<Transaction>
1366 where L::Target: Logger {
1367 self.inner.lock().unwrap().unsafe_get_latest_holder_commitment_txn(logger)
1370 /// Processes transactions in a newly connected block, which may result in any of the following:
1371 /// - update the monitor's state against resolved HTLCs
1372 /// - punish the counterparty in the case of seeing a revoked commitment transaction
1373 /// - force close the channel and claim/timeout incoming/outgoing HTLCs if near expiration
1374 /// - detect settled outputs for later spending
1375 /// - schedule and bump any in-flight claims
1377 /// Returns any new outputs to watch from `txdata`; after called, these are also included in
1378 /// [`get_outputs_to_watch`].
1380 /// [`get_outputs_to_watch`]: #method.get_outputs_to_watch
1381 pub fn block_connected<B: Deref, F: Deref, L: Deref>(
1383 header: &BlockHeader,
1384 txdata: &TransactionData,
1389 ) -> Vec<TransactionOutputs>
1391 B::Target: BroadcasterInterface,
1392 F::Target: FeeEstimator,
1395 self.inner.lock().unwrap().block_connected(
1396 header, txdata, height, broadcaster, fee_estimator, logger)
1399 /// Determines if the disconnected block contained any transactions of interest and updates
1401 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(
1403 header: &BlockHeader,
1409 B::Target: BroadcasterInterface,
1410 F::Target: FeeEstimator,
1413 self.inner.lock().unwrap().block_disconnected(
1414 header, height, broadcaster, fee_estimator, logger)
1417 /// Processes transactions confirmed in a block with the given header and height, returning new
1418 /// outputs to watch. See [`block_connected`] for details.
1420 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1421 /// blocks. See [`chain::Confirm`] for calling expectations.
1423 /// [`block_connected`]: Self::block_connected
1424 pub fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
1426 header: &BlockHeader,
1427 txdata: &TransactionData,
1432 ) -> Vec<TransactionOutputs>
1434 B::Target: BroadcasterInterface,
1435 F::Target: FeeEstimator,
1438 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1439 self.inner.lock().unwrap().transactions_confirmed(
1440 header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
1443 /// Processes a transaction that was reorganized out of the chain.
1445 /// Used instead of [`block_disconnected`] by clients that are notified of transactions rather
1446 /// than blocks. See [`chain::Confirm`] for calling expectations.
1448 /// [`block_disconnected`]: Self::block_disconnected
1449 pub fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
1456 B::Target: BroadcasterInterface,
1457 F::Target: FeeEstimator,
1460 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1461 self.inner.lock().unwrap().transaction_unconfirmed(
1462 txid, broadcaster, &bounded_fee_estimator, logger);
1465 /// Updates the monitor with the current best chain tip, returning new outputs to watch. See
1466 /// [`block_connected`] for details.
1468 /// Used instead of [`block_connected`] by clients that are notified of transactions rather than
1469 /// blocks. See [`chain::Confirm`] for calling expectations.
1471 /// [`block_connected`]: Self::block_connected
1472 pub fn best_block_updated<B: Deref, F: Deref, L: Deref>(
1474 header: &BlockHeader,
1479 ) -> Vec<TransactionOutputs>
1481 B::Target: BroadcasterInterface,
1482 F::Target: FeeEstimator,
1485 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1486 self.inner.lock().unwrap().best_block_updated(
1487 header, height, broadcaster, &bounded_fee_estimator, logger)
1490 /// Returns the set of txids that should be monitored for re-organization out of the chain.
1491 pub fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
1492 let inner = self.inner.lock().unwrap();
1493 let mut txids: Vec<(Txid, Option<BlockHash>)> = inner.onchain_events_awaiting_threshold_conf
1495 .map(|entry| (entry.txid, entry.block_hash))
1496 .chain(inner.onchain_tx_handler.get_relevant_txids().into_iter())
1498 txids.sort_unstable();
1503 /// Gets the latest best block which was connected either via the [`chain::Listen`] or
1504 /// [`chain::Confirm`] interfaces.
1505 pub fn current_best_block(&self) -> BestBlock {
1506 self.inner.lock().unwrap().best_block.clone()
1509 /// Triggers rebroadcasts/fee-bumps of pending claims from a force-closed channel. This is
1510 /// crucial in preventing certain classes of pinning attacks, detecting substantial mempool
1511 /// feerate changes between blocks, and ensuring reliability if broadcasting fails. We recommend
1512 /// invoking this every 30 seconds, or lower if running in an environment with spotty
1513 /// connections, like on mobile.
1514 pub fn rebroadcast_pending_claims<B: Deref, F: Deref, L: Deref>(
1515 &self, broadcaster: B, fee_estimator: F, logger: L,
1518 B::Target: BroadcasterInterface,
1519 F::Target: FeeEstimator,
1522 let fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
1523 let mut inner = self.inner.lock().unwrap();
1524 let current_height = inner.best_block.height;
1525 inner.onchain_tx_handler.rebroadcast_pending_claims(
1526 current_height, &broadcaster, &fee_estimator, &logger,
1531 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
1532 /// Helper for get_claimable_balances which does the work for an individual HTLC, generating up
1533 /// to one `Balance` for the HTLC.
1534 fn get_htlc_balance(&self, htlc: &HTLCOutputInCommitment, holder_commitment: bool,
1535 counterparty_revoked_commitment: bool, confirmed_txid: Option<Txid>)
1536 -> Option<Balance> {
1537 let htlc_commitment_tx_output_idx =
1538 if let Some(v) = htlc.transaction_output_index { v } else { return None; };
1540 let mut htlc_spend_txid_opt = None;
1541 let mut htlc_spend_tx_opt = None;
1542 let mut holder_timeout_spend_pending = None;
1543 let mut htlc_spend_pending = None;
1544 let mut holder_delayed_output_pending = None;
1545 for event in self.onchain_events_awaiting_threshold_conf.iter() {
1547 OnchainEvent::HTLCUpdate { commitment_tx_output_idx, htlc_value_satoshis, .. }
1548 if commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) => {
1549 debug_assert!(htlc_spend_txid_opt.is_none());
1550 htlc_spend_txid_opt = Some(&event.txid);
1551 debug_assert!(htlc_spend_tx_opt.is_none());
1552 htlc_spend_tx_opt = event.transaction.as_ref();
1553 debug_assert!(holder_timeout_spend_pending.is_none());
1554 debug_assert_eq!(htlc_value_satoshis.unwrap(), htlc.amount_msat / 1000);
1555 holder_timeout_spend_pending = Some(event.confirmation_threshold());
1557 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. }
1558 if commitment_tx_output_idx == htlc_commitment_tx_output_idx => {
1559 debug_assert!(htlc_spend_txid_opt.is_none());
1560 htlc_spend_txid_opt = Some(&event.txid);
1561 debug_assert!(htlc_spend_tx_opt.is_none());
1562 htlc_spend_tx_opt = event.transaction.as_ref();
1563 debug_assert!(htlc_spend_pending.is_none());
1564 htlc_spend_pending = Some((event.confirmation_threshold(), preimage.is_some()));
1566 OnchainEvent::MaturingOutput {
1567 descriptor: SpendableOutputDescriptor::DelayedPaymentOutput(ref descriptor) }
1568 if descriptor.outpoint.index as u32 == htlc_commitment_tx_output_idx => {
1569 debug_assert!(holder_delayed_output_pending.is_none());
1570 holder_delayed_output_pending = Some(event.confirmation_threshold());
1575 let htlc_resolved = self.htlcs_resolved_on_chain.iter()
1576 .find(|v| if v.commitment_tx_output_idx == Some(htlc_commitment_tx_output_idx) {
1577 debug_assert!(htlc_spend_txid_opt.is_none());
1578 htlc_spend_txid_opt = v.resolving_txid.as_ref();
1579 debug_assert!(htlc_spend_tx_opt.is_none());
1580 htlc_spend_tx_opt = v.resolving_tx.as_ref();
1583 debug_assert!(holder_timeout_spend_pending.is_some() as u8 + htlc_spend_pending.is_some() as u8 + htlc_resolved.is_some() as u8 <= 1);
1585 let htlc_commitment_outpoint = BitcoinOutPoint::new(confirmed_txid.unwrap(), htlc_commitment_tx_output_idx);
1586 let htlc_output_to_spend =
1587 if let Some(txid) = htlc_spend_txid_opt {
1588 // Because HTLC transactions either only have 1 input and 1 output (pre-anchors) or
1589 // are signed with SIGHASH_SINGLE|ANYONECANPAY under BIP-0143 (post-anchors), we can
1590 // locate the correct output by ensuring its adjacent input spends the HTLC output
1591 // in the commitment.
1592 if let Some(ref tx) = htlc_spend_tx_opt {
1593 let htlc_input_idx_opt = tx.input.iter().enumerate()
1594 .find(|(_, input)| input.previous_output == htlc_commitment_outpoint)
1595 .map(|(idx, _)| idx as u32);
1596 debug_assert!(htlc_input_idx_opt.is_some());
1597 BitcoinOutPoint::new(*txid, htlc_input_idx_opt.unwrap_or(0))
1599 debug_assert!(!self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx());
1600 BitcoinOutPoint::new(*txid, 0)
1603 htlc_commitment_outpoint
1605 let htlc_output_spend_pending = self.onchain_tx_handler.is_output_spend_pending(&htlc_output_to_spend);
1607 if let Some(conf_thresh) = holder_delayed_output_pending {
1608 debug_assert!(holder_commitment);
1609 return Some(Balance::ClaimableAwaitingConfirmations {
1610 claimable_amount_satoshis: htlc.amount_msat / 1000,
1611 confirmation_height: conf_thresh,
1613 } else if htlc_resolved.is_some() && !htlc_output_spend_pending {
1614 // Funding transaction spends should be fully confirmed by the time any
1615 // HTLC transactions are resolved, unless we're talking about a holder
1616 // commitment tx, whose resolution is delayed until the CSV timeout is
1617 // reached, even though HTLCs may be resolved after only
1618 // ANTI_REORG_DELAY confirmations.
1619 debug_assert!(holder_commitment || self.funding_spend_confirmed.is_some());
1620 } else if counterparty_revoked_commitment {
1621 let htlc_output_claim_pending = self.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1622 if let OnchainEvent::MaturingOutput {
1623 descriptor: SpendableOutputDescriptor::StaticOutput { .. }
1625 if event.transaction.as_ref().map(|tx| tx.input.iter().any(|inp| {
1626 if let Some(htlc_spend_txid) = htlc_spend_txid_opt {
1627 tx.txid() == *htlc_spend_txid || inp.previous_output.txid == *htlc_spend_txid
1629 Some(inp.previous_output.txid) == confirmed_txid &&
1630 inp.previous_output.vout == htlc_commitment_tx_output_idx
1632 })).unwrap_or(false) {
1637 if htlc_output_claim_pending.is_some() {
1638 // We already push `Balance`s onto the `res` list for every
1639 // `StaticOutput` in a `MaturingOutput` in the revoked
1640 // counterparty commitment transaction case generally, so don't
1641 // need to do so again here.
1643 debug_assert!(holder_timeout_spend_pending.is_none(),
1644 "HTLCUpdate OnchainEvents should never appear for preimage claims");
1645 debug_assert!(!htlc.offered || htlc_spend_pending.is_none() || !htlc_spend_pending.unwrap().1,
1646 "We don't (currently) generate preimage claims against revoked outputs, where did you get one?!");
1647 return Some(Balance::CounterpartyRevokedOutputClaimable {
1648 claimable_amount_satoshis: htlc.amount_msat / 1000,
1651 } else if htlc.offered == holder_commitment {
1652 // If the payment was outbound, check if there's an HTLCUpdate
1653 // indicating we have spent this HTLC with a timeout, claiming it back
1654 // and awaiting confirmations on it.
1655 if let Some(conf_thresh) = holder_timeout_spend_pending {
1656 return Some(Balance::ClaimableAwaitingConfirmations {
1657 claimable_amount_satoshis: htlc.amount_msat / 1000,
1658 confirmation_height: conf_thresh,
1661 return Some(Balance::MaybeTimeoutClaimableHTLC {
1662 claimable_amount_satoshis: htlc.amount_msat / 1000,
1663 claimable_height: htlc.cltv_expiry,
1664 payment_hash: htlc.payment_hash,
1667 } else if let Some(payment_preimage) = self.payment_preimages.get(&htlc.payment_hash) {
1668 // Otherwise (the payment was inbound), only expose it as claimable if
1669 // we know the preimage.
1670 // Note that if there is a pending claim, but it did not use the
1671 // preimage, we lost funds to our counterparty! We will then continue
1672 // to show it as ContentiousClaimable until ANTI_REORG_DELAY.
1673 debug_assert!(holder_timeout_spend_pending.is_none());
1674 if let Some((conf_thresh, true)) = htlc_spend_pending {
1675 return Some(Balance::ClaimableAwaitingConfirmations {
1676 claimable_amount_satoshis: htlc.amount_msat / 1000,
1677 confirmation_height: conf_thresh,
1680 return Some(Balance::ContentiousClaimable {
1681 claimable_amount_satoshis: htlc.amount_msat / 1000,
1682 timeout_height: htlc.cltv_expiry,
1683 payment_hash: htlc.payment_hash,
1684 payment_preimage: *payment_preimage,
1687 } else if htlc_resolved.is_none() {
1688 return Some(Balance::MaybePreimageClaimableHTLC {
1689 claimable_amount_satoshis: htlc.amount_msat / 1000,
1690 expiry_height: htlc.cltv_expiry,
1691 payment_hash: htlc.payment_hash,
1698 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitor<Signer> {
1699 /// Gets the balances in this channel which are either claimable by us if we were to
1700 /// force-close the channel now or which are claimable on-chain (possibly awaiting
1703 /// Any balances in the channel which are available on-chain (excluding on-chain fees) are
1704 /// included here until an [`Event::SpendableOutputs`] event has been generated for the
1705 /// balance, or until our counterparty has claimed the balance and accrued several
1706 /// confirmations on the claim transaction.
1708 /// Note that for `ChannelMonitors` which track a channel which went on-chain with versions of
1709 /// LDK prior to 0.0.111, balances may not be fully captured if our counterparty broadcasted
1710 /// a revoked state.
1712 /// See [`Balance`] for additional details on the types of claimable balances which
1713 /// may be returned here and their meanings.
1714 pub fn get_claimable_balances(&self) -> Vec<Balance> {
1715 let mut res = Vec::new();
1716 let us = self.inner.lock().unwrap();
1718 let mut confirmed_txid = us.funding_spend_confirmed;
1719 let mut confirmed_counterparty_output = us.confirmed_commitment_tx_counterparty_output;
1720 let mut pending_commitment_tx_conf_thresh = None;
1721 let funding_spend_pending = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1722 if let OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } =
1725 confirmed_counterparty_output = commitment_tx_to_counterparty_output;
1726 Some((event.txid, event.confirmation_threshold()))
1729 if let Some((txid, conf_thresh)) = funding_spend_pending {
1730 debug_assert!(us.funding_spend_confirmed.is_none(),
1731 "We have a pending funding spend awaiting anti-reorg confirmation, we can't have confirmed it already!");
1732 confirmed_txid = Some(txid);
1733 pending_commitment_tx_conf_thresh = Some(conf_thresh);
1736 macro_rules! walk_htlcs {
1737 ($holder_commitment: expr, $counterparty_revoked_commitment: expr, $htlc_iter: expr) => {
1738 for htlc in $htlc_iter {
1739 if htlc.transaction_output_index.is_some() {
1741 if let Some(bal) = us.get_htlc_balance(htlc, $holder_commitment, $counterparty_revoked_commitment, confirmed_txid) {
1749 if let Some(txid) = confirmed_txid {
1750 let mut found_commitment_tx = false;
1751 if let Some(counterparty_tx_htlcs) = us.counterparty_claimable_outpoints.get(&txid) {
1752 // First look for the to_remote output back to us.
1753 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1754 if let Some(value) = us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1755 if let OnchainEvent::MaturingOutput {
1756 descriptor: SpendableOutputDescriptor::StaticPaymentOutput(descriptor)
1758 Some(descriptor.output.value)
1761 res.push(Balance::ClaimableAwaitingConfirmations {
1762 claimable_amount_satoshis: value,
1763 confirmation_height: conf_thresh,
1766 // If a counterparty commitment transaction is awaiting confirmation, we
1767 // should either have a StaticPaymentOutput MaturingOutput event awaiting
1768 // confirmation with the same height or have never met our dust amount.
1771 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1772 walk_htlcs!(false, false, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1774 walk_htlcs!(false, true, counterparty_tx_htlcs.iter().map(|(a, _)| a));
1775 // The counterparty broadcasted a revoked state!
1776 // Look for any StaticOutputs first, generating claimable balances for those.
1777 // If any match the confirmed counterparty revoked to_self output, skip
1778 // generating a CounterpartyRevokedOutputClaimable.
1779 let mut spent_counterparty_output = false;
1780 for event in us.onchain_events_awaiting_threshold_conf.iter() {
1781 if let OnchainEvent::MaturingOutput {
1782 descriptor: SpendableOutputDescriptor::StaticOutput { output, .. }
1784 res.push(Balance::ClaimableAwaitingConfirmations {
1785 claimable_amount_satoshis: output.value,
1786 confirmation_height: event.confirmation_threshold(),
1788 if let Some(confirmed_to_self_idx) = confirmed_counterparty_output.map(|(idx, _)| idx) {
1789 if event.transaction.as_ref().map(|tx|
1790 tx.input.iter().any(|inp| inp.previous_output.vout == confirmed_to_self_idx)
1791 ).unwrap_or(false) {
1792 spent_counterparty_output = true;
1798 if spent_counterparty_output {
1799 } else if let Some((confirmed_to_self_idx, amt)) = confirmed_counterparty_output {
1800 let output_spendable = us.onchain_tx_handler
1801 .is_output_spend_pending(&BitcoinOutPoint::new(txid, confirmed_to_self_idx));
1802 if output_spendable {
1803 res.push(Balance::CounterpartyRevokedOutputClaimable {
1804 claimable_amount_satoshis: amt,
1808 // Counterparty output is missing, either it was broadcasted on a
1809 // previous version of LDK or the counterparty hadn't met dust.
1812 found_commitment_tx = true;
1813 } else if txid == us.current_holder_commitment_tx.txid {
1814 walk_htlcs!(true, false, us.current_holder_commitment_tx.htlc_outputs.iter().map(|(a, _, _)| a));
1815 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1816 res.push(Balance::ClaimableAwaitingConfirmations {
1817 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1818 confirmation_height: conf_thresh,
1821 found_commitment_tx = true;
1822 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1823 if txid == prev_commitment.txid {
1824 walk_htlcs!(true, false, prev_commitment.htlc_outputs.iter().map(|(a, _, _)| a));
1825 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1826 res.push(Balance::ClaimableAwaitingConfirmations {
1827 claimable_amount_satoshis: prev_commitment.to_self_value_sat,
1828 confirmation_height: conf_thresh,
1831 found_commitment_tx = true;
1834 if !found_commitment_tx {
1835 if let Some(conf_thresh) = pending_commitment_tx_conf_thresh {
1836 // We blindly assume this is a cooperative close transaction here, and that
1837 // neither us nor our counterparty misbehaved. At worst we've under-estimated
1838 // the amount we can claim as we'll punish a misbehaving counterparty.
1839 res.push(Balance::ClaimableAwaitingConfirmations {
1840 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat,
1841 confirmation_height: conf_thresh,
1846 let mut claimable_inbound_htlc_value_sat = 0;
1847 for (htlc, _, _) in us.current_holder_commitment_tx.htlc_outputs.iter() {
1848 if htlc.transaction_output_index.is_none() { continue; }
1850 res.push(Balance::MaybeTimeoutClaimableHTLC {
1851 claimable_amount_satoshis: htlc.amount_msat / 1000,
1852 claimable_height: htlc.cltv_expiry,
1853 payment_hash: htlc.payment_hash,
1855 } else if us.payment_preimages.get(&htlc.payment_hash).is_some() {
1856 claimable_inbound_htlc_value_sat += htlc.amount_msat / 1000;
1858 // As long as the HTLC is still in our latest commitment state, treat
1859 // it as potentially claimable, even if it has long-since expired.
1860 res.push(Balance::MaybePreimageClaimableHTLC {
1861 claimable_amount_satoshis: htlc.amount_msat / 1000,
1862 expiry_height: htlc.cltv_expiry,
1863 payment_hash: htlc.payment_hash,
1867 res.push(Balance::ClaimableOnChannelClose {
1868 claimable_amount_satoshis: us.current_holder_commitment_tx.to_self_value_sat + claimable_inbound_htlc_value_sat,
1875 /// Gets the set of outbound HTLCs which can be (or have been) resolved by this
1876 /// `ChannelMonitor`. This is used to determine if an HTLC was removed from the channel prior
1877 /// to the `ChannelManager` having been persisted.
1879 /// This is similar to [`Self::get_pending_or_resolved_outbound_htlcs`] except it includes
1880 /// HTLCs which were resolved on-chain (i.e. where the final HTLC resolution was done by an
1881 /// event from this `ChannelMonitor`).
1882 pub(crate) fn get_all_current_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1883 let mut res = HashMap::new();
1884 // Just examine the available counterparty commitment transactions. See docs on
1885 // `fail_unbroadcast_htlcs`, below, for justification.
1886 let us = self.inner.lock().unwrap();
1887 macro_rules! walk_counterparty_commitment {
1889 if let Some(ref latest_outpoints) = us.counterparty_claimable_outpoints.get($txid) {
1890 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
1891 if let &Some(ref source) = source_option {
1892 res.insert((**source).clone(), (htlc.clone(),
1893 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned()));
1899 if let Some(ref txid) = us.current_counterparty_commitment_txid {
1900 walk_counterparty_commitment!(txid);
1902 if let Some(ref txid) = us.prev_counterparty_commitment_txid {
1903 walk_counterparty_commitment!(txid);
1908 /// Gets the set of outbound HTLCs which are pending resolution in this channel or which were
1909 /// resolved with a preimage from our counterparty.
1911 /// This is used to reconstruct pending outbound payments on restart in the ChannelManager.
1913 /// Currently, the preimage is unused, however if it is present in the relevant internal state
1914 /// an HTLC is always included even if it has been resolved.
1915 pub(crate) fn get_pending_or_resolved_outbound_htlcs(&self) -> HashMap<HTLCSource, (HTLCOutputInCommitment, Option<PaymentPreimage>)> {
1916 let us = self.inner.lock().unwrap();
1917 // We're only concerned with the confirmation count of HTLC transactions, and don't
1918 // actually care how many confirmations a commitment transaction may or may not have. Thus,
1919 // we look for either a FundingSpendConfirmation event or a funding_spend_confirmed.
1920 let confirmed_txid = us.funding_spend_confirmed.or_else(|| {
1921 us.onchain_events_awaiting_threshold_conf.iter().find_map(|event| {
1922 if let OnchainEvent::FundingSpendConfirmation { .. } = event.event {
1928 if confirmed_txid.is_none() {
1929 // If we have not seen a commitment transaction on-chain (ie the channel is not yet
1930 // closed), just get the full set.
1932 return self.get_all_current_outbound_htlcs();
1935 let mut res = HashMap::new();
1936 macro_rules! walk_htlcs {
1937 ($holder_commitment: expr, $htlc_iter: expr) => {
1938 for (htlc, source) in $htlc_iter {
1939 if us.htlcs_resolved_on_chain.iter().any(|v| v.commitment_tx_output_idx == htlc.transaction_output_index) {
1940 // We should assert that funding_spend_confirmed is_some() here, but we
1941 // have some unit tests which violate HTLC transaction CSVs entirely and
1943 // TODO: Once tests all connect transactions at consensus-valid times, we
1944 // should assert here like we do in `get_claimable_balances`.
1945 } else if htlc.offered == $holder_commitment {
1946 // If the payment was outbound, check if there's an HTLCUpdate
1947 // indicating we have spent this HTLC with a timeout, claiming it back
1948 // and awaiting confirmations on it.
1949 let htlc_update_confd = us.onchain_events_awaiting_threshold_conf.iter().any(|event| {
1950 if let OnchainEvent::HTLCUpdate { commitment_tx_output_idx: Some(commitment_tx_output_idx), .. } = event.event {
1951 // If the HTLC was timed out, we wait for ANTI_REORG_DELAY blocks
1952 // before considering it "no longer pending" - this matches when we
1953 // provide the ChannelManager an HTLC failure event.
1954 Some(commitment_tx_output_idx) == htlc.transaction_output_index &&
1955 us.best_block.height() >= event.height + ANTI_REORG_DELAY - 1
1956 } else if let OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, .. } = event.event {
1957 // If the HTLC was fulfilled with a preimage, we consider the HTLC
1958 // immediately non-pending, matching when we provide ChannelManager
1960 Some(commitment_tx_output_idx) == htlc.transaction_output_index
1963 let counterparty_resolved_preimage_opt =
1964 us.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).cloned();
1965 if !htlc_update_confd || counterparty_resolved_preimage_opt.is_some() {
1966 res.insert(source.clone(), (htlc.clone(), counterparty_resolved_preimage_opt));
1973 let txid = confirmed_txid.unwrap();
1974 if Some(txid) == us.current_counterparty_commitment_txid || Some(txid) == us.prev_counterparty_commitment_txid {
1975 walk_htlcs!(false, us.counterparty_claimable_outpoints.get(&txid).unwrap().iter().filter_map(|(a, b)| {
1976 if let &Some(ref source) = b {
1977 Some((a, &**source))
1980 } else if txid == us.current_holder_commitment_tx.txid {
1981 walk_htlcs!(true, us.current_holder_commitment_tx.htlc_outputs.iter().filter_map(|(a, _, c)| {
1982 if let Some(source) = c { Some((a, source)) } else { None }
1984 } else if let Some(prev_commitment) = &us.prev_holder_signed_commitment_tx {
1985 if txid == prev_commitment.txid {
1986 walk_htlcs!(true, prev_commitment.htlc_outputs.iter().filter_map(|(a, _, c)| {
1987 if let Some(source) = c { Some((a, source)) } else { None }
1995 pub(crate) fn get_stored_preimages(&self) -> HashMap<PaymentHash, PaymentPreimage> {
1996 self.inner.lock().unwrap().payment_preimages.clone()
2000 /// Compares a broadcasted commitment transaction's HTLCs with those in the latest state,
2001 /// failing any HTLCs which didn't make it into the broadcasted commitment transaction back
2002 /// after ANTI_REORG_DELAY blocks.
2004 /// We always compare against the set of HTLCs in counterparty commitment transactions, as those
2005 /// are the commitment transactions which are generated by us. The off-chain state machine in
2006 /// `Channel` will automatically resolve any HTLCs which were never included in a commitment
2007 /// transaction when it detects channel closure, but it is up to us to ensure any HTLCs which were
2008 /// included in a remote commitment transaction are failed back if they are not present in the
2009 /// broadcasted commitment transaction.
2011 /// Specifically, the removal process for HTLCs in `Channel` is always based on the counterparty
2012 /// sending a `revoke_and_ack`, which causes us to clear `prev_counterparty_commitment_txid`. Thus,
2013 /// as long as we examine both the current counterparty commitment transaction and, if it hasn't
2014 /// been revoked yet, the previous one, we we will never "forget" to resolve an HTLC.
2015 macro_rules! fail_unbroadcast_htlcs {
2016 ($self: expr, $commitment_tx_type: expr, $commitment_txid_confirmed: expr, $commitment_tx_confirmed: expr,
2017 $commitment_tx_conf_height: expr, $commitment_tx_conf_hash: expr, $confirmed_htlcs_list: expr, $logger: expr) => { {
2018 debug_assert_eq!($commitment_tx_confirmed.txid(), $commitment_txid_confirmed);
2020 macro_rules! check_htlc_fails {
2021 ($txid: expr, $commitment_tx: expr) => {
2022 if let Some(ref latest_outpoints) = $self.counterparty_claimable_outpoints.get($txid) {
2023 for &(ref htlc, ref source_option) in latest_outpoints.iter() {
2024 if let &Some(ref source) = source_option {
2025 // Check if the HTLC is present in the commitment transaction that was
2026 // broadcast, but not if it was below the dust limit, which we should
2027 // fail backwards immediately as there is no way for us to learn the
2028 // payment_preimage.
2029 // Note that if the dust limit were allowed to change between
2030 // commitment transactions we'd want to be check whether *any*
2031 // broadcastable commitment transaction has the HTLC in it, but it
2032 // cannot currently change after channel initialization, so we don't
2034 let confirmed_htlcs_iter: &mut Iterator<Item = (&HTLCOutputInCommitment, Option<&HTLCSource>)> = &mut $confirmed_htlcs_list;
2036 let mut matched_htlc = false;
2037 for (ref broadcast_htlc, ref broadcast_source) in confirmed_htlcs_iter {
2038 if broadcast_htlc.transaction_output_index.is_some() &&
2039 (Some(&**source) == *broadcast_source ||
2040 (broadcast_source.is_none() &&
2041 broadcast_htlc.payment_hash == htlc.payment_hash &&
2042 broadcast_htlc.amount_msat == htlc.amount_msat)) {
2043 matched_htlc = true;
2047 if matched_htlc { continue; }
2048 if $self.counterparty_fulfilled_htlcs.get(&SentHTLCId::from_source(source)).is_some() {
2051 $self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
2052 if entry.height != $commitment_tx_conf_height { return true; }
2054 OnchainEvent::HTLCUpdate { source: ref update_source, .. } => {
2055 *update_source != **source
2060 let entry = OnchainEventEntry {
2061 txid: $commitment_txid_confirmed,
2062 transaction: Some($commitment_tx_confirmed.clone()),
2063 height: $commitment_tx_conf_height,
2064 block_hash: Some(*$commitment_tx_conf_hash),
2065 event: OnchainEvent::HTLCUpdate {
2066 source: (**source).clone(),
2067 payment_hash: htlc.payment_hash.clone(),
2068 htlc_value_satoshis: Some(htlc.amount_msat / 1000),
2069 commitment_tx_output_idx: None,
2072 log_trace!($logger, "Failing HTLC with payment_hash {} from {} counterparty commitment tx due to broadcast of {} commitment transaction {}, waiting for confirmation (at height {})",
2073 log_bytes!(htlc.payment_hash.0), $commitment_tx, $commitment_tx_type,
2074 $commitment_txid_confirmed, entry.confirmation_threshold());
2075 $self.onchain_events_awaiting_threshold_conf.push(entry);
2081 if let Some(ref txid) = $self.current_counterparty_commitment_txid {
2082 check_htlc_fails!(txid, "current");
2084 if let Some(ref txid) = $self.prev_counterparty_commitment_txid {
2085 check_htlc_fails!(txid, "previous");
2090 // In the `test_invalid_funding_tx` test, we need a bogus script which matches the HTLC-Accepted
2091 // witness length match (ie is 136 bytes long). We generate one here which we also use in some
2092 // in-line tests later.
2095 pub fn deliberately_bogus_accepted_htlc_witness_program() -> Vec<u8> {
2096 let mut ret = [opcodes::all::OP_NOP.to_u8(); 136];
2097 ret[131] = opcodes::all::OP_DROP.to_u8();
2098 ret[132] = opcodes::all::OP_DROP.to_u8();
2099 ret[133] = opcodes::all::OP_DROP.to_u8();
2100 ret[134] = opcodes::all::OP_DROP.to_u8();
2101 ret[135] = opcodes::OP_TRUE.to_u8();
2106 pub fn deliberately_bogus_accepted_htlc_witness() -> Vec<Vec<u8>> {
2107 vec![Vec::new(), Vec::new(), Vec::new(), Vec::new(), deliberately_bogus_accepted_htlc_witness_program().into()].into()
2110 impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
2111 /// Inserts a revocation secret into this channel monitor. Prunes old preimages if neither
2112 /// needed by holder commitment transactions HTCLs nor by counterparty ones. Unless we haven't already seen
2113 /// counterparty commitment transaction's secret, they are de facto pruned (we can use revocation key).
2114 fn provide_secret(&mut self, idx: u64, secret: [u8; 32]) -> Result<(), &'static str> {
2115 if let Err(()) = self.commitment_secrets.provide_secret(idx, secret) {
2116 return Err("Previous secret did not match new one");
2119 // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
2120 // events for now-revoked/fulfilled HTLCs.
2121 if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
2122 if self.current_counterparty_commitment_txid.unwrap() != txid {
2123 let cur_claimables = self.counterparty_claimable_outpoints.get(
2124 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2125 for (_, ref source_opt) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
2126 if let Some(source) = source_opt {
2127 if !cur_claimables.iter()
2128 .any(|(_, cur_source_opt)| cur_source_opt == source_opt)
2130 self.counterparty_fulfilled_htlcs.remove(&SentHTLCId::from_source(source));
2134 for &mut (_, ref mut source_opt) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
2138 assert!(cfg!(fuzzing), "Commitment txids are unique outside of fuzzing, where hashes can collide");
2142 if !self.payment_preimages.is_empty() {
2143 let cur_holder_signed_commitment_tx = &self.current_holder_commitment_tx;
2144 let prev_holder_signed_commitment_tx = self.prev_holder_signed_commitment_tx.as_ref();
2145 let min_idx = self.get_min_seen_secret();
2146 let counterparty_hash_commitment_number = &mut self.counterparty_hash_commitment_number;
2148 self.payment_preimages.retain(|&k, _| {
2149 for &(ref htlc, _, _) in cur_holder_signed_commitment_tx.htlc_outputs.iter() {
2150 if k == htlc.payment_hash {
2154 if let Some(prev_holder_commitment_tx) = prev_holder_signed_commitment_tx {
2155 for &(ref htlc, _, _) in prev_holder_commitment_tx.htlc_outputs.iter() {
2156 if k == htlc.payment_hash {
2161 let contains = if let Some(cn) = counterparty_hash_commitment_number.get(&k) {
2168 counterparty_hash_commitment_number.remove(&k);
2177 pub(crate) fn provide_latest_counterparty_commitment_tx<L: Deref>(&mut self, txid: Txid, htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Box<HTLCSource>>)>, commitment_number: u64, their_per_commitment_point: PublicKey, logger: &L) where L::Target: Logger {
2178 // TODO: Encrypt the htlc_outputs data with the single-hash of the commitment transaction
2179 // so that a remote monitor doesn't learn anything unless there is a malicious close.
2180 // (only maybe, sadly we cant do the same for local info, as we need to be aware of
2182 for &(ref htlc, _) in &htlc_outputs {
2183 self.counterparty_hash_commitment_number.insert(htlc.payment_hash, commitment_number);
2186 log_trace!(logger, "Tracking new counterparty commitment transaction with txid {} at commitment number {} with {} HTLC outputs", txid, commitment_number, htlc_outputs.len());
2187 self.prev_counterparty_commitment_txid = self.current_counterparty_commitment_txid.take();
2188 self.current_counterparty_commitment_txid = Some(txid);
2189 self.counterparty_claimable_outpoints.insert(txid, htlc_outputs.clone());
2190 self.current_counterparty_commitment_number = commitment_number;
2191 //TODO: Merge this into the other per-counterparty-transaction output storage stuff
2192 match self.their_cur_per_commitment_points {
2193 Some(old_points) => {
2194 if old_points.0 == commitment_number + 1 {
2195 self.their_cur_per_commitment_points = Some((old_points.0, old_points.1, Some(their_per_commitment_point)));
2196 } else if old_points.0 == commitment_number + 2 {
2197 if let Some(old_second_point) = old_points.2 {
2198 self.their_cur_per_commitment_points = Some((old_points.0 - 1, old_second_point, Some(their_per_commitment_point)));
2200 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2203 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2207 self.their_cur_per_commitment_points = Some((commitment_number, their_per_commitment_point, None));
2210 let mut htlcs = Vec::with_capacity(htlc_outputs.len());
2211 for htlc in htlc_outputs {
2212 if htlc.0.transaction_output_index.is_some() {
2218 /// Informs this monitor of the latest holder (ie broadcastable) commitment transaction. The
2219 /// monitor watches for timeouts and may broadcast it if we approach such a timeout. Thus, it
2220 /// is important that any clones of this channel monitor (including remote clones) by kept
2221 /// up-to-date as our holder commitment transaction is updated.
2222 /// Panics if set_on_holder_tx_csv has never been called.
2223 fn provide_latest_holder_commitment_tx(&mut self, holder_commitment_tx: HolderCommitmentTransaction, mut htlc_outputs: Vec<(HTLCOutputInCommitment, Option<Signature>, Option<HTLCSource>)>, claimed_htlcs: &[(SentHTLCId, PaymentPreimage)], nondust_htlc_sources: Vec<HTLCSource>) -> Result<(), &'static str> {
2224 if htlc_outputs.iter().any(|(_, s, _)| s.is_some()) {
2225 // If we have non-dust HTLCs in htlc_outputs, ensure they match the HTLCs in the
2226 // `holder_commitment_tx`. In the future, we'll no longer provide the redundant data
2227 // and just pass in source data via `nondust_htlc_sources`.
2228 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.trust().htlcs().len());
2229 for (a, b) in htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).map(|(h, _, _)| h).zip(holder_commitment_tx.trust().htlcs().iter()) {
2230 debug_assert_eq!(a, b);
2232 debug_assert_eq!(htlc_outputs.iter().filter(|(_, s, _)| s.is_some()).count(), holder_commitment_tx.counterparty_htlc_sigs.len());
2233 for (a, b) in htlc_outputs.iter().filter_map(|(_, s, _)| s.as_ref()).zip(holder_commitment_tx.counterparty_htlc_sigs.iter()) {
2234 debug_assert_eq!(a, b);
2236 debug_assert!(nondust_htlc_sources.is_empty());
2238 // If we don't have any non-dust HTLCs in htlc_outputs, assume they were all passed via
2239 // `nondust_htlc_sources`, building up the final htlc_outputs by combining
2240 // `nondust_htlc_sources` and the `holder_commitment_tx`
2241 #[cfg(debug_assertions)] {
2243 for htlc in holder_commitment_tx.trust().htlcs().iter() {
2244 assert!(htlc.transaction_output_index.unwrap() as i32 > prev);
2245 prev = htlc.transaction_output_index.unwrap() as i32;
2248 debug_assert!(htlc_outputs.iter().all(|(htlc, _, _)| htlc.transaction_output_index.is_none()));
2249 debug_assert!(htlc_outputs.iter().all(|(_, sig_opt, _)| sig_opt.is_none()));
2250 debug_assert_eq!(holder_commitment_tx.trust().htlcs().len(), holder_commitment_tx.counterparty_htlc_sigs.len());
2252 let mut sources_iter = nondust_htlc_sources.into_iter();
2254 for (htlc, counterparty_sig) in holder_commitment_tx.trust().htlcs().iter()
2255 .zip(holder_commitment_tx.counterparty_htlc_sigs.iter())
2258 let source = sources_iter.next().expect("Non-dust HTLC sources didn't match commitment tx");
2259 #[cfg(debug_assertions)] {
2260 assert!(source.possibly_matches_output(htlc));
2262 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), Some(source)));
2264 htlc_outputs.push((htlc.clone(), Some(counterparty_sig.clone()), None));
2267 debug_assert!(sources_iter.next().is_none());
2270 let trusted_tx = holder_commitment_tx.trust();
2271 let txid = trusted_tx.txid();
2272 let tx_keys = trusted_tx.keys();
2273 self.current_holder_commitment_number = trusted_tx.commitment_number();
2274 let mut new_holder_commitment_tx = HolderSignedTx {
2276 revocation_key: tx_keys.revocation_key,
2277 a_htlc_key: tx_keys.broadcaster_htlc_key,
2278 b_htlc_key: tx_keys.countersignatory_htlc_key,
2279 delayed_payment_key: tx_keys.broadcaster_delayed_payment_key,
2280 per_commitment_point: tx_keys.per_commitment_point,
2282 to_self_value_sat: holder_commitment_tx.to_broadcaster_value_sat(),
2283 feerate_per_kw: trusted_tx.feerate_per_kw(),
2285 self.onchain_tx_handler.provide_latest_holder_tx(holder_commitment_tx);
2286 mem::swap(&mut new_holder_commitment_tx, &mut self.current_holder_commitment_tx);
2287 self.prev_holder_signed_commitment_tx = Some(new_holder_commitment_tx);
2288 for (claimed_htlc_id, claimed_preimage) in claimed_htlcs {
2289 #[cfg(debug_assertions)] {
2290 let cur_counterparty_htlcs = self.counterparty_claimable_outpoints.get(
2291 &self.current_counterparty_commitment_txid.unwrap()).unwrap();
2292 assert!(cur_counterparty_htlcs.iter().any(|(_, source_opt)| {
2293 if let Some(source) = source_opt {
2294 SentHTLCId::from_source(source) == *claimed_htlc_id
2298 self.counterparty_fulfilled_htlcs.insert(*claimed_htlc_id, *claimed_preimage);
2300 if self.holder_tx_signed {
2301 return Err("Latest holder commitment signed has already been signed, update is rejected");
2306 /// Provides a payment_hash->payment_preimage mapping. Will be automatically pruned when all
2307 /// commitment_tx_infos which contain the payment hash have been revoked.
2308 fn provide_payment_preimage<B: Deref, F: Deref, L: Deref>(
2309 &mut self, payment_hash: &PaymentHash, payment_preimage: &PaymentPreimage, broadcaster: &B,
2310 fee_estimator: &LowerBoundedFeeEstimator<F>, logger: &L)
2311 where B::Target: BroadcasterInterface,
2312 F::Target: FeeEstimator,
2315 self.payment_preimages.insert(payment_hash.clone(), payment_preimage.clone());
2317 // If the channel is force closed, try to claim the output from this preimage.
2318 // First check if a counterparty commitment transaction has been broadcasted:
2319 macro_rules! claim_htlcs {
2320 ($commitment_number: expr, $txid: expr) => {
2321 let (htlc_claim_reqs, _) = self.get_counterparty_output_claim_info($commitment_number, $txid, None);
2322 self.onchain_tx_handler.update_claims_view_from_requests(htlc_claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2325 if let Some(txid) = self.current_counterparty_commitment_txid {
2326 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2327 claim_htlcs!(*commitment_number, txid);
2331 if let Some(txid) = self.prev_counterparty_commitment_txid {
2332 if let Some(commitment_number) = self.counterparty_commitment_txn_on_chain.get(&txid) {
2333 claim_htlcs!(*commitment_number, txid);
2338 // Then if a holder commitment transaction has been seen on-chain, broadcast transactions
2339 // claiming the HTLC output from each of the holder commitment transactions.
2340 // Note that we can't just use `self.holder_tx_signed`, because that only covers the case where
2341 // *we* sign a holder commitment transaction, not when e.g. a watchtower broadcasts one of our
2342 // holder commitment transactions.
2343 if self.broadcasted_holder_revokable_script.is_some() {
2344 // Assume that the broadcasted commitment transaction confirmed in the current best
2345 // block. Even if not, its a reasonable metric for the bump criteria on the HTLC
2347 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
2348 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2349 if let Some(ref tx) = self.prev_holder_signed_commitment_tx {
2350 let (claim_reqs, _) = self.get_broadcasted_holder_claims(&tx, self.best_block.height());
2351 self.onchain_tx_handler.update_claims_view_from_requests(claim_reqs, self.best_block.height(), self.best_block.height(), broadcaster, fee_estimator, logger);
2356 pub(crate) fn broadcast_latest_holder_commitment_txn<B: Deref, L: Deref>(&mut self, broadcaster: &B, logger: &L)
2357 where B::Target: BroadcasterInterface,
2360 let commit_txs = self.get_latest_holder_commitment_txn(logger);
2361 let mut txs = vec![];
2362 for tx in commit_txs.iter() {
2363 log_info!(logger, "Broadcasting local {}", log_tx!(tx));
2366 broadcaster.broadcast_transactions(&txs);
2367 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
2370 pub fn update_monitor<B: Deref, F: Deref, L: Deref>(&mut self, updates: &ChannelMonitorUpdate, broadcaster: &B, fee_estimator: F, logger: &L) -> Result<(), ()>
2371 where B::Target: BroadcasterInterface,
2372 F::Target: FeeEstimator,
2375 if self.latest_update_id == CLOSED_CHANNEL_UPDATE_ID && updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2376 log_info!(logger, "Applying post-force-closed update to monitor {} with {} change(s).",
2377 log_funding_info!(self), updates.updates.len());
2378 } else if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2379 log_info!(logger, "Applying force close update to monitor {} with {} change(s).",
2380 log_funding_info!(self), updates.updates.len());
2382 log_info!(logger, "Applying update to monitor {}, bringing update_id from {} to {} with {} change(s).",
2383 log_funding_info!(self), self.latest_update_id, updates.update_id, updates.updates.len());
2385 // ChannelMonitor updates may be applied after force close if we receive a preimage for a
2386 // broadcasted commitment transaction HTLC output that we'd like to claim on-chain. If this
2387 // is the case, we no longer have guaranteed access to the monitor's update ID, so we use a
2388 // sentinel value instead.
2390 // The `ChannelManager` may also queue redundant `ChannelForceClosed` updates if it still
2391 // thinks the channel needs to have its commitment transaction broadcast, so we'll allow
2393 if updates.update_id == CLOSED_CHANNEL_UPDATE_ID {
2394 assert_eq!(updates.updates.len(), 1);
2395 match updates.updates[0] {
2396 ChannelMonitorUpdateStep::ChannelForceClosed { .. } => {},
2397 // We should have already seen a `ChannelForceClosed` update if we're trying to
2398 // provide a preimage at this point.
2399 ChannelMonitorUpdateStep::PaymentPreimage { .. } =>
2400 debug_assert_eq!(self.latest_update_id, CLOSED_CHANNEL_UPDATE_ID),
2402 log_error!(logger, "Attempted to apply post-force-close ChannelMonitorUpdate of type {}", updates.updates[0].variant_name());
2403 panic!("Attempted to apply post-force-close ChannelMonitorUpdate that wasn't providing a payment preimage");
2406 } else if self.latest_update_id + 1 != updates.update_id {
2407 panic!("Attempted to apply ChannelMonitorUpdates out of order, check the update_id before passing an update to update_monitor!");
2409 let mut ret = Ok(());
2410 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&*fee_estimator);
2411 for update in updates.updates.iter() {
2413 ChannelMonitorUpdateStep::LatestHolderCommitmentTXInfo { commitment_tx, htlc_outputs, claimed_htlcs, nondust_htlc_sources } => {
2414 log_trace!(logger, "Updating ChannelMonitor with latest holder commitment transaction info");
2415 if self.lockdown_from_offchain { panic!(); }
2416 if let Err(e) = self.provide_latest_holder_commitment_tx(commitment_tx.clone(), htlc_outputs.clone(), &claimed_htlcs, nondust_htlc_sources.clone()) {
2417 log_error!(logger, "Providing latest holder commitment transaction failed/was refused:");
2418 log_error!(logger, " {}", e);
2422 ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { commitment_txid, htlc_outputs, commitment_number, their_per_commitment_point } => {
2423 log_trace!(logger, "Updating ChannelMonitor with latest counterparty commitment transaction info");
2424 self.provide_latest_counterparty_commitment_tx(*commitment_txid, htlc_outputs.clone(), *commitment_number, *their_per_commitment_point, logger)
2426 ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage } => {
2427 log_trace!(logger, "Updating ChannelMonitor with payment preimage");
2428 self.provide_payment_preimage(&PaymentHash(Sha256::hash(&payment_preimage.0[..]).into_inner()), &payment_preimage, broadcaster, &bounded_fee_estimator, logger)
2430 ChannelMonitorUpdateStep::CommitmentSecret { idx, secret } => {
2431 log_trace!(logger, "Updating ChannelMonitor with commitment secret");
2432 if let Err(e) = self.provide_secret(*idx, *secret) {
2433 log_error!(logger, "Providing latest counterparty commitment secret failed/was refused:");
2434 log_error!(logger, " {}", e);
2438 ChannelMonitorUpdateStep::ChannelForceClosed { should_broadcast } => {
2439 log_trace!(logger, "Updating ChannelMonitor: channel force closed, should broadcast: {}", should_broadcast);
2440 self.lockdown_from_offchain = true;
2441 if *should_broadcast {
2442 // There's no need to broadcast our commitment transaction if we've seen one
2443 // confirmed (even with 1 confirmation) as it'll be rejected as
2444 // duplicate/conflicting.
2445 let detected_funding_spend = self.funding_spend_confirmed.is_some() ||
2446 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
2447 OnchainEvent::FundingSpendConfirmation { .. } => true,
2450 if detected_funding_spend {
2451 log_trace!(logger, "Avoiding commitment broadcast, already detected confirmed spend onchain");
2454 self.broadcast_latest_holder_commitment_txn(broadcaster, logger);
2455 // If the channel supports anchor outputs, we'll need to emit an external
2456 // event to be consumed such that a child transaction is broadcast with a
2457 // high enough feerate for the parent commitment transaction to confirm.
2458 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
2459 let funding_output = HolderFundingOutput::build(
2460 self.funding_redeemscript.clone(), self.channel_value_satoshis,
2461 self.onchain_tx_handler.channel_type_features().clone(),
2463 let best_block_height = self.best_block.height();
2464 let commitment_package = PackageTemplate::build_package(
2465 self.funding_info.0.txid.clone(), self.funding_info.0.index as u32,
2466 PackageSolvingData::HolderFundingOutput(funding_output),
2467 best_block_height, best_block_height
2469 self.onchain_tx_handler.update_claims_view_from_requests(
2470 vec![commitment_package], best_block_height, best_block_height,
2471 broadcaster, &bounded_fee_estimator, logger,
2474 } else if !self.holder_tx_signed {
2475 log_error!(logger, "WARNING: You have a potentially-unsafe holder commitment transaction available to broadcast");
2476 log_error!(logger, " in channel monitor for channel {}!", log_bytes!(self.funding_info.0.to_channel_id()));
2477 log_error!(logger, " Read the docs for ChannelMonitor::get_latest_holder_commitment_txn and take manual action!");
2479 // If we generated a MonitorEvent::CommitmentTxConfirmed, the ChannelManager
2480 // will still give us a ChannelForceClosed event with !should_broadcast, but we
2481 // shouldn't print the scary warning above.
2482 log_info!(logger, "Channel off-chain state closed after we broadcasted our latest commitment transaction.");
2485 ChannelMonitorUpdateStep::ShutdownScript { scriptpubkey } => {
2486 log_trace!(logger, "Updating ChannelMonitor with shutdown script");
2487 if let Some(shutdown_script) = self.shutdown_script.replace(scriptpubkey.clone()) {
2488 panic!("Attempted to replace shutdown script {} with {}", shutdown_script, scriptpubkey);
2494 // If the updates succeeded and we were in an already closed channel state, then there's no
2495 // need to refuse any updates we expect to receive afer seeing a confirmed commitment.
2496 if ret.is_ok() && updates.update_id == CLOSED_CHANNEL_UPDATE_ID && self.latest_update_id == updates.update_id {
2500 self.latest_update_id = updates.update_id;
2502 // Refuse updates after we've detected a spend onchain, but only if we haven't processed a
2503 // force closed monitor update yet.
2504 if ret.is_ok() && self.funding_spend_seen && self.latest_update_id != CLOSED_CHANNEL_UPDATE_ID {
2505 log_error!(logger, "Refusing Channel Monitor Update as counterparty attempted to update commitment after funding was spent");
2510 pub fn get_latest_update_id(&self) -> u64 {
2511 self.latest_update_id
2514 pub fn get_funding_txo(&self) -> &(OutPoint, Script) {
2518 pub fn get_outputs_to_watch(&self) -> &HashMap<Txid, Vec<(u32, Script)>> {
2519 // If we've detected a counterparty commitment tx on chain, we must include it in the set
2520 // of outputs to watch for spends of, otherwise we're likely to lose user funds. Because
2521 // its trivial to do, double-check that here.
2522 for (txid, _) in self.counterparty_commitment_txn_on_chain.iter() {
2523 self.outputs_to_watch.get(txid).expect("Counterparty commitment txn which have been broadcast should have outputs registered");
2525 &self.outputs_to_watch
2528 pub fn get_and_clear_pending_monitor_events(&mut self) -> Vec<MonitorEvent> {
2529 let mut ret = Vec::new();
2530 mem::swap(&mut ret, &mut self.pending_monitor_events);
2534 pub fn get_and_clear_pending_events(&mut self) -> Vec<Event> {
2535 let mut ret = Vec::new();
2536 mem::swap(&mut ret, &mut self.pending_events);
2537 for (claim_id, claim_event) in self.onchain_tx_handler.get_and_clear_pending_claim_events().drain(..) {
2539 ClaimEvent::BumpCommitment {
2540 package_target_feerate_sat_per_1000_weight, commitment_tx, anchor_output_idx,
2542 let commitment_txid = commitment_tx.txid();
2543 debug_assert_eq!(self.current_holder_commitment_tx.txid, commitment_txid);
2544 let pending_htlcs = self.current_holder_commitment_tx.non_dust_htlcs();
2545 let commitment_tx_fee_satoshis = self.channel_value_satoshis -
2546 commitment_tx.output.iter().fold(0u64, |sum, output| sum + output.value);
2547 ret.push(Event::BumpTransaction(BumpTransactionEvent::ChannelClose {
2549 package_target_feerate_sat_per_1000_weight,
2551 commitment_tx_fee_satoshis,
2552 anchor_descriptor: AnchorDescriptor {
2553 channel_keys_id: self.channel_keys_id,
2554 channel_value_satoshis: self.channel_value_satoshis,
2555 outpoint: BitcoinOutPoint {
2556 txid: commitment_txid,
2557 vout: anchor_output_idx,
2563 ClaimEvent::BumpHTLC {
2564 target_feerate_sat_per_1000_weight, htlcs, tx_lock_time,
2566 let mut htlc_descriptors = Vec::with_capacity(htlcs.len());
2568 htlc_descriptors.push(HTLCDescriptor {
2569 channel_keys_id: self.channel_keys_id,
2570 channel_value_satoshis: self.channel_value_satoshis,
2571 channel_parameters: self.onchain_tx_handler.channel_transaction_parameters.clone(),
2572 commitment_txid: htlc.commitment_txid,
2573 per_commitment_number: htlc.per_commitment_number,
2575 preimage: htlc.preimage,
2576 counterparty_sig: htlc.counterparty_sig,
2579 ret.push(Event::BumpTransaction(BumpTransactionEvent::HTLCResolution {
2581 target_feerate_sat_per_1000_weight,
2591 /// Can only fail if idx is < get_min_seen_secret
2592 fn get_secret(&self, idx: u64) -> Option<[u8; 32]> {
2593 self.commitment_secrets.get_secret(idx)
2596 pub(crate) fn get_min_seen_secret(&self) -> u64 {
2597 self.commitment_secrets.get_min_seen_secret()
2600 pub(crate) fn get_cur_counterparty_commitment_number(&self) -> u64 {
2601 self.current_counterparty_commitment_number
2604 pub(crate) fn get_cur_holder_commitment_number(&self) -> u64 {
2605 self.current_holder_commitment_number
2608 /// Attempts to claim a counterparty commitment transaction's outputs using the revocation key and
2609 /// data in counterparty_claimable_outpoints. Will directly claim any HTLC outputs which expire at a
2610 /// height > height + CLTV_SHARED_CLAIM_BUFFER. In any case, will install monitoring for
2611 /// HTLC-Success/HTLC-Timeout transactions.
2613 /// Returns packages to claim the revoked output(s), as well as additional outputs to watch and
2614 /// general information about the output that is to the counterparty in the commitment
2616 fn check_spend_counterparty_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L)
2617 -> (Vec<PackageTemplate>, TransactionOutputs, CommitmentTxCounterpartyOutputInfo)
2618 where L::Target: Logger {
2619 // Most secp and related errors trying to create keys means we have no hope of constructing
2620 // a spend transaction...so we return no transactions to broadcast
2621 let mut claimable_outpoints = Vec::new();
2622 let mut watch_outputs = Vec::new();
2623 let mut to_counterparty_output_info = None;
2625 let commitment_txid = tx.txid(); //TODO: This is gonna be a performance bottleneck for watchtowers!
2626 let per_commitment_option = self.counterparty_claimable_outpoints.get(&commitment_txid);
2628 macro_rules! ignore_error {
2629 ( $thing : expr ) => {
2632 Err(_) => return (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2637 let commitment_number = 0xffffffffffff - ((((tx.input[0].sequence.0 as u64 & 0xffffff) << 3*8) | (tx.lock_time.0 as u64 & 0xffffff)) ^ self.commitment_transaction_number_obscure_factor);
2638 if commitment_number >= self.get_min_seen_secret() {
2639 let secret = self.get_secret(commitment_number).unwrap();
2640 let per_commitment_key = ignore_error!(SecretKey::from_slice(&secret));
2641 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2642 let revocation_pubkey = chan_utils::derive_public_revocation_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2643 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx, &PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key), &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
2645 let revokeable_redeemscript = chan_utils::get_revokeable_redeemscript(&revocation_pubkey, self.counterparty_commitment_params.on_counterparty_tx_csv, &delayed_key);
2646 let revokeable_p2wsh = revokeable_redeemscript.to_v0_p2wsh();
2648 // First, process non-htlc outputs (to_holder & to_counterparty)
2649 for (idx, outp) in tx.output.iter().enumerate() {
2650 if outp.script_pubkey == revokeable_p2wsh {
2651 let revk_outp = RevokedOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, outp.value, self.counterparty_commitment_params.on_counterparty_tx_csv, self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx());
2652 let justice_package = PackageTemplate::build_package(commitment_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp), height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height);
2653 claimable_outpoints.push(justice_package);
2654 to_counterparty_output_info =
2655 Some((idx.try_into().expect("Txn can't have more than 2^32 outputs"), outp.value));
2659 // Then, try to find revoked htlc outputs
2660 if let Some(ref per_commitment_data) = per_commitment_option {
2661 for (_, &(ref htlc, _)) in per_commitment_data.iter().enumerate() {
2662 if let Some(transaction_output_index) = htlc.transaction_output_index {
2663 if transaction_output_index as usize >= tx.output.len() ||
2664 tx.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2665 // per_commitment_data is corrupt or our commitment signing key leaked!
2666 return (claimable_outpoints, (commitment_txid, watch_outputs),
2667 to_counterparty_output_info);
2669 let revk_htlc_outp = RevokedHTLCOutput::build(per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key, self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key, htlc.amount_msat / 1000, htlc.clone(), &self.onchain_tx_handler.channel_transaction_parameters.channel_type_features);
2670 let justice_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, PackageSolvingData::RevokedHTLCOutput(revk_htlc_outp), htlc.cltv_expiry, height);
2671 claimable_outpoints.push(justice_package);
2676 // Last, track onchain revoked commitment transaction and fail backward outgoing HTLCs as payment path is broken
2677 if !claimable_outpoints.is_empty() || per_commitment_option.is_some() { // ie we're confident this is actually ours
2678 // We're definitely a counterparty commitment transaction!
2679 log_error!(logger, "Got broadcast of revoked counterparty commitment transaction, going to generate general spend tx with {} inputs", claimable_outpoints.len());
2680 for (idx, outp) in tx.output.iter().enumerate() {
2681 watch_outputs.push((idx as u32, outp.clone()));
2683 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2685 if let Some(per_commitment_data) = per_commitment_option {
2686 fail_unbroadcast_htlcs!(self, "revoked_counterparty", commitment_txid, tx, height,
2687 block_hash, per_commitment_data.iter().map(|(htlc, htlc_source)|
2688 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2691 debug_assert!(false, "We should have per-commitment option for any recognized old commitment txn");
2692 fail_unbroadcast_htlcs!(self, "revoked counterparty", commitment_txid, tx, height,
2693 block_hash, [].iter().map(|reference| *reference), logger);
2696 } else if let Some(per_commitment_data) = per_commitment_option {
2697 // While this isn't useful yet, there is a potential race where if a counterparty
2698 // revokes a state at the same time as the commitment transaction for that state is
2699 // confirmed, and the watchtower receives the block before the user, the user could
2700 // upload a new ChannelMonitor with the revocation secret but the watchtower has
2701 // already processed the block, resulting in the counterparty_commitment_txn_on_chain entry
2702 // not being generated by the above conditional. Thus, to be safe, we go ahead and
2704 for (idx, outp) in tx.output.iter().enumerate() {
2705 watch_outputs.push((idx as u32, outp.clone()));
2707 self.counterparty_commitment_txn_on_chain.insert(commitment_txid, commitment_number);
2709 log_info!(logger, "Got broadcast of non-revoked counterparty commitment transaction {}", commitment_txid);
2710 fail_unbroadcast_htlcs!(self, "counterparty", commitment_txid, tx, height, block_hash,
2711 per_commitment_data.iter().map(|(htlc, htlc_source)|
2712 (htlc, htlc_source.as_ref().map(|htlc_source| htlc_source.as_ref()))
2715 let (htlc_claim_reqs, counterparty_output_info) =
2716 self.get_counterparty_output_claim_info(commitment_number, commitment_txid, Some(tx));
2717 to_counterparty_output_info = counterparty_output_info;
2718 for req in htlc_claim_reqs {
2719 claimable_outpoints.push(req);
2723 (claimable_outpoints, (commitment_txid, watch_outputs), to_counterparty_output_info)
2726 /// Returns the HTLC claim package templates and the counterparty output info
2727 fn get_counterparty_output_claim_info(&self, commitment_number: u64, commitment_txid: Txid, tx: Option<&Transaction>)
2728 -> (Vec<PackageTemplate>, CommitmentTxCounterpartyOutputInfo) {
2729 let mut claimable_outpoints = Vec::new();
2730 let mut to_counterparty_output_info: CommitmentTxCounterpartyOutputInfo = None;
2732 let htlc_outputs = match self.counterparty_claimable_outpoints.get(&commitment_txid) {
2733 Some(outputs) => outputs,
2734 None => return (claimable_outpoints, to_counterparty_output_info),
2736 let per_commitment_points = match self.their_cur_per_commitment_points {
2737 Some(points) => points,
2738 None => return (claimable_outpoints, to_counterparty_output_info),
2741 let per_commitment_point =
2742 // If the counterparty commitment tx is the latest valid state, use their latest
2743 // per-commitment point
2744 if per_commitment_points.0 == commitment_number { &per_commitment_points.1 }
2745 else if let Some(point) = per_commitment_points.2.as_ref() {
2746 // If counterparty commitment tx is the state previous to the latest valid state, use
2747 // their previous per-commitment point (non-atomicity of revocation means it's valid for
2748 // them to temporarily have two valid commitment txns from our viewpoint)
2749 if per_commitment_points.0 == commitment_number + 1 {
2751 } else { return (claimable_outpoints, to_counterparty_output_info); }
2752 } else { return (claimable_outpoints, to_counterparty_output_info); };
2754 if let Some(transaction) = tx {
2755 let revocation_pubkey = chan_utils::derive_public_revocation_key(
2756 &self.onchain_tx_handler.secp_ctx, &per_commitment_point, &self.holder_revocation_basepoint);
2757 let delayed_key = chan_utils::derive_public_key(&self.onchain_tx_handler.secp_ctx,
2758 &per_commitment_point,
2759 &self.counterparty_commitment_params.counterparty_delayed_payment_base_key);
2760 let revokeable_p2wsh = chan_utils::get_revokeable_redeemscript(&revocation_pubkey,
2761 self.counterparty_commitment_params.on_counterparty_tx_csv,
2762 &delayed_key).to_v0_p2wsh();
2763 for (idx, outp) in transaction.output.iter().enumerate() {
2764 if outp.script_pubkey == revokeable_p2wsh {
2765 to_counterparty_output_info =
2766 Some((idx.try_into().expect("Can't have > 2^32 outputs"), outp.value));
2771 for (_, &(ref htlc, _)) in htlc_outputs.iter().enumerate() {
2772 if let Some(transaction_output_index) = htlc.transaction_output_index {
2773 if let Some(transaction) = tx {
2774 if transaction_output_index as usize >= transaction.output.len() ||
2775 transaction.output[transaction_output_index as usize].value != htlc.amount_msat / 1000 {
2776 // per_commitment_data is corrupt or our commitment signing key leaked!
2777 return (claimable_outpoints, to_counterparty_output_info);
2780 let preimage = if htlc.offered { if let Some(p) = self.payment_preimages.get(&htlc.payment_hash) { Some(*p) } else { None } } else { None };
2781 if preimage.is_some() || !htlc.offered {
2782 let counterparty_htlc_outp = if htlc.offered {
2783 PackageSolvingData::CounterpartyOfferedHTLCOutput(
2784 CounterpartyOfferedHTLCOutput::build(*per_commitment_point,
2785 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2786 self.counterparty_commitment_params.counterparty_htlc_base_key,
2787 preimage.unwrap(), htlc.clone(), self.onchain_tx_handler.channel_type_features().clone()))
2789 PackageSolvingData::CounterpartyReceivedHTLCOutput(
2790 CounterpartyReceivedHTLCOutput::build(*per_commitment_point,
2791 self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2792 self.counterparty_commitment_params.counterparty_htlc_base_key,
2793 htlc.clone(), self.onchain_tx_handler.channel_type_features().clone()))
2795 let counterparty_package = PackageTemplate::build_package(commitment_txid, transaction_output_index, counterparty_htlc_outp, htlc.cltv_expiry, 0);
2796 claimable_outpoints.push(counterparty_package);
2801 (claimable_outpoints, to_counterparty_output_info)
2804 /// Attempts to claim a counterparty HTLC-Success/HTLC-Timeout's outputs using the revocation key
2805 fn check_spend_counterparty_htlc<L: Deref>(
2806 &mut self, tx: &Transaction, commitment_number: u64, commitment_txid: &Txid, height: u32, logger: &L
2807 ) -> (Vec<PackageTemplate>, Option<TransactionOutputs>) where L::Target: Logger {
2808 let secret = if let Some(secret) = self.get_secret(commitment_number) { secret } else { return (Vec::new(), None); };
2809 let per_commitment_key = match SecretKey::from_slice(&secret) {
2811 Err(_) => return (Vec::new(), None)
2813 let per_commitment_point = PublicKey::from_secret_key(&self.onchain_tx_handler.secp_ctx, &per_commitment_key);
2815 let htlc_txid = tx.txid();
2816 let mut claimable_outpoints = vec![];
2817 let mut outputs_to_watch = None;
2818 // Previously, we would only claim HTLCs from revoked HTLC transactions if they had 1 input
2819 // with a witness of 5 elements and 1 output. This wasn't enough for anchor outputs, as the
2820 // counterparty can now aggregate multiple HTLCs into a single transaction thanks to
2821 // `SIGHASH_SINGLE` remote signatures, leading us to not claim any HTLCs upon seeing a
2822 // confirmed revoked HTLC transaction (for more details, see
2823 // https://lists.linuxfoundation.org/pipermail/lightning-dev/2022-April/003561.html).
2825 // We make sure we're not vulnerable to this case by checking all inputs of the transaction,
2826 // and claim those which spend the commitment transaction, have a witness of 5 elements, and
2827 // have a corresponding output at the same index within the transaction.
2828 for (idx, input) in tx.input.iter().enumerate() {
2829 if input.previous_output.txid == *commitment_txid && input.witness.len() == 5 && tx.output.get(idx).is_some() {
2830 log_error!(logger, "Got broadcast of revoked counterparty HTLC transaction, spending {}:{}", htlc_txid, idx);
2831 let revk_outp = RevokedOutput::build(
2832 per_commitment_point, self.counterparty_commitment_params.counterparty_delayed_payment_base_key,
2833 self.counterparty_commitment_params.counterparty_htlc_base_key, per_commitment_key,
2834 tx.output[idx].value, self.counterparty_commitment_params.on_counterparty_tx_csv,
2837 let justice_package = PackageTemplate::build_package(
2838 htlc_txid, idx as u32, PackageSolvingData::RevokedOutput(revk_outp),
2839 height + self.counterparty_commitment_params.on_counterparty_tx_csv as u32, height
2841 claimable_outpoints.push(justice_package);
2842 if outputs_to_watch.is_none() {
2843 outputs_to_watch = Some((htlc_txid, vec![]));
2845 outputs_to_watch.as_mut().unwrap().1.push((idx as u32, tx.output[idx].clone()));
2848 (claimable_outpoints, outputs_to_watch)
2851 // Returns (1) `PackageTemplate`s that can be given to the OnchainTxHandler, so that the handler can
2852 // broadcast transactions claiming holder HTLC commitment outputs and (2) a holder revokable
2853 // script so we can detect whether a holder transaction has been seen on-chain.
2854 fn get_broadcasted_holder_claims(&self, holder_tx: &HolderSignedTx, conf_height: u32) -> (Vec<PackageTemplate>, Option<(Script, PublicKey, PublicKey)>) {
2855 let mut claim_requests = Vec::with_capacity(holder_tx.htlc_outputs.len());
2857 let redeemscript = chan_utils::get_revokeable_redeemscript(&holder_tx.revocation_key, self.on_holder_tx_csv, &holder_tx.delayed_payment_key);
2858 let broadcasted_holder_revokable_script = Some((redeemscript.to_v0_p2wsh(), holder_tx.per_commitment_point.clone(), holder_tx.revocation_key.clone()));
2860 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2861 if let Some(transaction_output_index) = htlc.transaction_output_index {
2862 let htlc_output = if htlc.offered {
2863 let htlc_output = HolderHTLCOutput::build_offered(
2864 htlc.amount_msat, htlc.cltv_expiry, self.onchain_tx_handler.channel_type_features().clone()
2868 let payment_preimage = if let Some(preimage) = self.payment_preimages.get(&htlc.payment_hash) {
2871 // We can't build an HTLC-Success transaction without the preimage
2874 let htlc_output = HolderHTLCOutput::build_accepted(
2875 payment_preimage, htlc.amount_msat, self.onchain_tx_handler.channel_type_features().clone()
2879 let htlc_package = PackageTemplate::build_package(
2880 holder_tx.txid, transaction_output_index,
2881 PackageSolvingData::HolderHTLCOutput(htlc_output),
2882 htlc.cltv_expiry, conf_height
2884 claim_requests.push(htlc_package);
2888 (claim_requests, broadcasted_holder_revokable_script)
2891 // Returns holder HTLC outputs to watch and react to in case of spending.
2892 fn get_broadcasted_holder_watch_outputs(&self, holder_tx: &HolderSignedTx, commitment_tx: &Transaction) -> Vec<(u32, TxOut)> {
2893 let mut watch_outputs = Vec::with_capacity(holder_tx.htlc_outputs.len());
2894 for &(ref htlc, _, _) in holder_tx.htlc_outputs.iter() {
2895 if let Some(transaction_output_index) = htlc.transaction_output_index {
2896 watch_outputs.push((transaction_output_index, commitment_tx.output[transaction_output_index as usize].clone()));
2902 /// Attempts to claim any claimable HTLCs in a commitment transaction which was not (yet)
2903 /// revoked using data in holder_claimable_outpoints.
2904 /// Should not be used if check_spend_revoked_transaction succeeds.
2905 /// Returns None unless the transaction is definitely one of our commitment transactions.
2906 fn check_spend_holder_transaction<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) -> Option<(Vec<PackageTemplate>, TransactionOutputs)> where L::Target: Logger {
2907 let commitment_txid = tx.txid();
2908 let mut claim_requests = Vec::new();
2909 let mut watch_outputs = Vec::new();
2911 macro_rules! append_onchain_update {
2912 ($updates: expr, $to_watch: expr) => {
2913 claim_requests = $updates.0;
2914 self.broadcasted_holder_revokable_script = $updates.1;
2915 watch_outputs.append(&mut $to_watch);
2919 // HTLCs set may differ between last and previous holder commitment txn, in case of one them hitting chain, ensure we cancel all HTLCs backward
2920 let mut is_holder_tx = false;
2922 if self.current_holder_commitment_tx.txid == commitment_txid {
2923 is_holder_tx = true;
2924 log_info!(logger, "Got broadcast of latest holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2925 let res = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, height);
2926 let mut to_watch = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, tx);
2927 append_onchain_update!(res, to_watch);
2928 fail_unbroadcast_htlcs!(self, "latest holder", commitment_txid, tx, height,
2929 block_hash, self.current_holder_commitment_tx.htlc_outputs.iter()
2930 .map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())), logger);
2931 } else if let &Some(ref holder_tx) = &self.prev_holder_signed_commitment_tx {
2932 if holder_tx.txid == commitment_txid {
2933 is_holder_tx = true;
2934 log_info!(logger, "Got broadcast of previous holder commitment tx {}, searching for available HTLCs to claim", commitment_txid);
2935 let res = self.get_broadcasted_holder_claims(holder_tx, height);
2936 let mut to_watch = self.get_broadcasted_holder_watch_outputs(holder_tx, tx);
2937 append_onchain_update!(res, to_watch);
2938 fail_unbroadcast_htlcs!(self, "previous holder", commitment_txid, tx, height, block_hash,
2939 holder_tx.htlc_outputs.iter().map(|(htlc, _, htlc_source)| (htlc, htlc_source.as_ref())),
2945 Some((claim_requests, (commitment_txid, watch_outputs)))
2951 pub fn get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2952 log_debug!(logger, "Getting signed latest holder commitment transaction!");
2953 self.holder_tx_signed = true;
2954 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
2955 let txid = commitment_tx.txid();
2956 let mut holder_transactions = vec![commitment_tx];
2957 // When anchor outputs are present, the HTLC transactions are only valid once the commitment
2958 // transaction confirms.
2959 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
2960 return holder_transactions;
2962 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
2963 if let Some(vout) = htlc.0.transaction_output_index {
2964 let preimage = if !htlc.0.offered {
2965 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
2966 // We can't build an HTLC-Success transaction without the preimage
2969 } else if htlc.0.cltv_expiry > self.best_block.height() + 1 {
2970 // Don't broadcast HTLC-Timeout transactions immediately as they don't meet the
2971 // current locktime requirements on-chain. We will broadcast them in
2972 // `block_confirmed` when `should_broadcast_holder_commitment_txn` returns true.
2973 // Note that we add + 1 as transactions are broadcastable when they can be
2974 // confirmed in the next block.
2977 if let Some(htlc_tx) = self.onchain_tx_handler.get_fully_signed_htlc_tx(
2978 &::bitcoin::OutPoint { txid, vout }, &preimage) {
2979 holder_transactions.push(htlc_tx);
2983 // 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.
2984 // The data will be re-generated and tracked in check_spend_holder_transaction if we get a confirmation.
2988 #[cfg(any(test,feature = "unsafe_revoked_tx_signing"))]
2989 /// Note that this includes possibly-locktimed-in-the-future transactions!
2990 fn unsafe_get_latest_holder_commitment_txn<L: Deref>(&mut self, logger: &L) -> Vec<Transaction> where L::Target: Logger {
2991 log_debug!(logger, "Getting signed copy of latest holder commitment transaction!");
2992 let commitment_tx = self.onchain_tx_handler.get_fully_signed_copy_holder_tx(&self.funding_redeemscript);
2993 let txid = commitment_tx.txid();
2994 let mut holder_transactions = vec![commitment_tx];
2995 // When anchor outputs are present, the HTLC transactions are only final once the commitment
2996 // transaction confirms due to the CSV 1 encumberance.
2997 if self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
2998 return holder_transactions;
3000 for htlc in self.current_holder_commitment_tx.htlc_outputs.iter() {
3001 if let Some(vout) = htlc.0.transaction_output_index {
3002 let preimage = if !htlc.0.offered {
3003 if let Some(preimage) = self.payment_preimages.get(&htlc.0.payment_hash) { Some(preimage.clone()) } else {
3004 // We can't build an HTLC-Success transaction without the preimage
3008 if let Some(htlc_tx) = self.onchain_tx_handler.unsafe_get_fully_signed_htlc_tx(
3009 &::bitcoin::OutPoint { txid, vout }, &preimage) {
3010 holder_transactions.push(htlc_tx);
3017 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>
3018 where B::Target: BroadcasterInterface,
3019 F::Target: FeeEstimator,
3022 let block_hash = header.block_hash();
3023 self.best_block = BestBlock::new(block_hash, height);
3025 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3026 self.transactions_confirmed(header, txdata, height, broadcaster, &bounded_fee_estimator, logger)
3029 fn best_block_updated<B: Deref, F: Deref, L: Deref>(
3031 header: &BlockHeader,
3034 fee_estimator: &LowerBoundedFeeEstimator<F>,
3036 ) -> Vec<TransactionOutputs>
3038 B::Target: BroadcasterInterface,
3039 F::Target: FeeEstimator,
3042 let block_hash = header.block_hash();
3044 if height > self.best_block.height() {
3045 self.best_block = BestBlock::new(block_hash, height);
3046 self.block_confirmed(height, block_hash, vec![], vec![], vec![], &broadcaster, &fee_estimator, &logger)
3047 } else if block_hash != self.best_block.block_hash() {
3048 self.best_block = BestBlock::new(block_hash, height);
3049 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height <= height);
3050 self.onchain_tx_handler.block_disconnected(height + 1, broadcaster, fee_estimator, logger);
3052 } else { Vec::new() }
3055 fn transactions_confirmed<B: Deref, F: Deref, L: Deref>(
3057 header: &BlockHeader,
3058 txdata: &TransactionData,
3061 fee_estimator: &LowerBoundedFeeEstimator<F>,
3063 ) -> Vec<TransactionOutputs>
3065 B::Target: BroadcasterInterface,
3066 F::Target: FeeEstimator,
3069 let txn_matched = self.filter_block(txdata);
3070 for tx in &txn_matched {
3071 let mut output_val = 0;
3072 for out in tx.output.iter() {
3073 if out.value > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3074 output_val += out.value;
3075 if output_val > 21_000_000_0000_0000 { panic!("Value-overflowing transaction provided to block connected"); }
3079 let block_hash = header.block_hash();
3081 let mut watch_outputs = Vec::new();
3082 let mut claimable_outpoints = Vec::new();
3083 'tx_iter: for tx in &txn_matched {
3084 let txid = tx.txid();
3085 // If a transaction has already been confirmed, ensure we don't bother processing it duplicatively.
3086 if Some(txid) == self.funding_spend_confirmed {
3087 log_debug!(logger, "Skipping redundant processing of funding-spend tx {} as it was previously confirmed", txid);
3090 for ev in self.onchain_events_awaiting_threshold_conf.iter() {
3091 if ev.txid == txid {
3092 if let Some(conf_hash) = ev.block_hash {
3093 assert_eq!(header.block_hash(), conf_hash,
3094 "Transaction {} was already confirmed and is being re-confirmed in a different block.\n\
3095 This indicates a severe bug in the transaction connection logic - a reorg should have been processed first!", ev.txid);
3097 log_debug!(logger, "Skipping redundant processing of confirming tx {} as it was previously confirmed", txid);
3101 for htlc in self.htlcs_resolved_on_chain.iter() {
3102 if Some(txid) == htlc.resolving_txid {
3103 log_debug!(logger, "Skipping redundant processing of HTLC resolution tx {} as it was previously confirmed", txid);
3107 for spendable_txid in self.spendable_txids_confirmed.iter() {
3108 if txid == *spendable_txid {
3109 log_debug!(logger, "Skipping redundant processing of spendable tx {} as it was previously confirmed", txid);
3114 if tx.input.len() == 1 {
3115 // Assuming our keys were not leaked (in which case we're screwed no matter what),
3116 // commitment transactions and HTLC transactions will all only ever have one input
3117 // (except for HTLC transactions for channels with anchor outputs), which is an easy
3118 // way to filter out any potential non-matching txn for lazy filters.
3119 let prevout = &tx.input[0].previous_output;
3120 if prevout.txid == self.funding_info.0.txid && prevout.vout == self.funding_info.0.index as u32 {
3121 let mut balance_spendable_csv = None;
3122 log_info!(logger, "Channel {} closed by funding output spend in txid {}.",
3123 log_bytes!(self.funding_info.0.to_channel_id()), txid);
3124 self.funding_spend_seen = true;
3125 let mut commitment_tx_to_counterparty_output = None;
3126 if (tx.input[0].sequence.0 >> 8*3) as u8 == 0x80 && (tx.lock_time.0 >> 8*3) as u8 == 0x20 {
3127 let (mut new_outpoints, new_outputs, counterparty_output_idx_sats) =
3128 self.check_spend_counterparty_transaction(&tx, height, &block_hash, &logger);
3129 commitment_tx_to_counterparty_output = counterparty_output_idx_sats;
3130 if !new_outputs.1.is_empty() {
3131 watch_outputs.push(new_outputs);
3133 claimable_outpoints.append(&mut new_outpoints);
3134 if new_outpoints.is_empty() {
3135 if let Some((mut new_outpoints, new_outputs)) = self.check_spend_holder_transaction(&tx, height, &block_hash, &logger) {
3136 debug_assert!(commitment_tx_to_counterparty_output.is_none(),
3137 "A commitment transaction matched as both a counterparty and local commitment tx?");
3138 if !new_outputs.1.is_empty() {
3139 watch_outputs.push(new_outputs);
3141 claimable_outpoints.append(&mut new_outpoints);
3142 balance_spendable_csv = Some(self.on_holder_tx_csv);
3146 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3148 transaction: Some((*tx).clone()),
3150 block_hash: Some(block_hash),
3151 event: OnchainEvent::FundingSpendConfirmation {
3152 on_local_output_csv: balance_spendable_csv,
3153 commitment_tx_to_counterparty_output,
3158 if tx.input.len() >= 1 {
3159 // While all commitment transactions have one input, HTLC transactions may have more
3160 // if the HTLC was present in an anchor channel. HTLCs can also be resolved in a few
3161 // other ways which can have more than one output.
3162 for tx_input in &tx.input {
3163 let commitment_txid = tx_input.previous_output.txid;
3164 if let Some(&commitment_number) = self.counterparty_commitment_txn_on_chain.get(&commitment_txid) {
3165 let (mut new_outpoints, new_outputs_option) = self.check_spend_counterparty_htlc(
3166 &tx, commitment_number, &commitment_txid, height, &logger
3168 claimable_outpoints.append(&mut new_outpoints);
3169 if let Some(new_outputs) = new_outputs_option {
3170 watch_outputs.push(new_outputs);
3172 // Since there may be multiple HTLCs for this channel (all spending the
3173 // same commitment tx) being claimed by the counterparty within the same
3174 // transaction, and `check_spend_counterparty_htlc` already checks all the
3175 // ones relevant to this channel, we can safely break from our loop.
3179 self.is_resolving_htlc_output(&tx, height, &block_hash, &logger);
3181 self.is_paying_spendable_output(&tx, height, &block_hash, &logger);
3185 if height > self.best_block.height() {
3186 self.best_block = BestBlock::new(block_hash, height);
3189 self.block_confirmed(height, block_hash, txn_matched, watch_outputs, claimable_outpoints, &broadcaster, &fee_estimator, &logger)
3192 /// Update state for new block(s)/transaction(s) confirmed. Note that the caller must update
3193 /// `self.best_block` before calling if a new best blockchain tip is available. More
3194 /// concretely, `self.best_block` must never be at a lower height than `conf_height`, avoiding
3195 /// complexity especially in
3196 /// `OnchainTx::update_claims_view_from_requests`/`OnchainTx::update_claims_view_from_matched_txn`.
3198 /// `conf_height` should be set to the height at which any new transaction(s)/block(s) were
3199 /// confirmed at, even if it is not the current best height.
3200 fn block_confirmed<B: Deref, F: Deref, L: Deref>(
3203 conf_hash: BlockHash,
3204 txn_matched: Vec<&Transaction>,
3205 mut watch_outputs: Vec<TransactionOutputs>,
3206 mut claimable_outpoints: Vec<PackageTemplate>,
3208 fee_estimator: &LowerBoundedFeeEstimator<F>,
3210 ) -> Vec<TransactionOutputs>
3212 B::Target: BroadcasterInterface,
3213 F::Target: FeeEstimator,
3216 log_trace!(logger, "Processing {} matched transactions for block at height {}.", txn_matched.len(), conf_height);
3217 debug_assert!(self.best_block.height() >= conf_height);
3219 let should_broadcast = self.should_broadcast_holder_commitment_txn(logger);
3220 if should_broadcast {
3221 let funding_outp = HolderFundingOutput::build(self.funding_redeemscript.clone(), self.channel_value_satoshis, self.onchain_tx_handler.channel_type_features().clone());
3222 let commitment_package = PackageTemplate::build_package(self.funding_info.0.txid.clone(), self.funding_info.0.index as u32, PackageSolvingData::HolderFundingOutput(funding_outp), self.best_block.height(), self.best_block.height());
3223 claimable_outpoints.push(commitment_package);
3224 self.pending_monitor_events.push(MonitorEvent::CommitmentTxConfirmed(self.funding_info.0));
3225 let commitment_tx = self.onchain_tx_handler.get_fully_signed_holder_tx(&self.funding_redeemscript);
3226 self.holder_tx_signed = true;
3227 // We can't broadcast our HTLC transactions while the commitment transaction is
3228 // unconfirmed. We'll delay doing so until we detect the confirmed commitment in
3229 // `transactions_confirmed`.
3230 if !self.onchain_tx_handler.channel_type_features().supports_anchors_zero_fee_htlc_tx() {
3231 // Because we're broadcasting a commitment transaction, we should construct the package
3232 // assuming it gets confirmed in the next block. Sadly, we have code which considers
3233 // "not yet confirmed" things as discardable, so we cannot do that here.
3234 let (mut new_outpoints, _) = self.get_broadcasted_holder_claims(&self.current_holder_commitment_tx, self.best_block.height());
3235 let new_outputs = self.get_broadcasted_holder_watch_outputs(&self.current_holder_commitment_tx, &commitment_tx);
3236 if !new_outputs.is_empty() {
3237 watch_outputs.push((self.current_holder_commitment_tx.txid.clone(), new_outputs));
3239 claimable_outpoints.append(&mut new_outpoints);
3243 // Find which on-chain events have reached their confirmation threshold.
3244 let onchain_events_awaiting_threshold_conf =
3245 self.onchain_events_awaiting_threshold_conf.drain(..).collect::<Vec<_>>();
3246 let mut onchain_events_reaching_threshold_conf = Vec::new();
3247 for entry in onchain_events_awaiting_threshold_conf {
3248 if entry.has_reached_confirmation_threshold(&self.best_block) {
3249 onchain_events_reaching_threshold_conf.push(entry);
3251 self.onchain_events_awaiting_threshold_conf.push(entry);
3255 // Used to check for duplicate HTLC resolutions.
3256 #[cfg(debug_assertions)]
3257 let unmatured_htlcs: Vec<_> = self.onchain_events_awaiting_threshold_conf
3259 .filter_map(|entry| match &entry.event {
3260 OnchainEvent::HTLCUpdate { source, .. } => Some(source),
3264 #[cfg(debug_assertions)]
3265 let mut matured_htlcs = Vec::new();
3267 // Produce actionable events from on-chain events having reached their threshold.
3268 for entry in onchain_events_reaching_threshold_conf.drain(..) {
3270 OnchainEvent::HTLCUpdate { ref source, payment_hash, htlc_value_satoshis, commitment_tx_output_idx } => {
3271 // Check for duplicate HTLC resolutions.
3272 #[cfg(debug_assertions)]
3275 unmatured_htlcs.iter().find(|&htlc| htlc == &source).is_none(),
3276 "An unmature HTLC transaction conflicts with a maturing one; failed to \
3277 call either transaction_unconfirmed for the conflicting transaction \
3278 or block_disconnected for a block containing it.");
3280 matured_htlcs.iter().find(|&htlc| htlc == source).is_none(),
3281 "A matured HTLC transaction conflicts with a maturing one; failed to \
3282 call either transaction_unconfirmed for the conflicting transaction \
3283 or block_disconnected for a block containing it.");
3284 matured_htlcs.push(source.clone());
3287 log_debug!(logger, "HTLC {} failure update in {} has got enough confirmations to be passed upstream",
3288 log_bytes!(payment_hash.0), entry.txid);
3289 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3291 payment_preimage: None,
3292 source: source.clone(),
3293 htlc_value_satoshis,
3295 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3296 commitment_tx_output_idx,
3297 resolving_txid: Some(entry.txid),
3298 resolving_tx: entry.transaction,
3299 payment_preimage: None,
3302 OnchainEvent::MaturingOutput { descriptor } => {
3303 log_debug!(logger, "Descriptor {} has got enough confirmations to be passed upstream", log_spendable!(descriptor));
3304 self.pending_events.push(Event::SpendableOutputs {
3305 outputs: vec![descriptor]
3307 self.spendable_txids_confirmed.push(entry.txid);
3309 OnchainEvent::HTLCSpendConfirmation { commitment_tx_output_idx, preimage, .. } => {
3310 self.htlcs_resolved_on_chain.push(IrrevocablyResolvedHTLC {
3311 commitment_tx_output_idx: Some(commitment_tx_output_idx),
3312 resolving_txid: Some(entry.txid),
3313 resolving_tx: entry.transaction,
3314 payment_preimage: preimage,
3317 OnchainEvent::FundingSpendConfirmation { commitment_tx_to_counterparty_output, .. } => {
3318 self.funding_spend_confirmed = Some(entry.txid);
3319 self.confirmed_commitment_tx_counterparty_output = commitment_tx_to_counterparty_output;
3324 self.onchain_tx_handler.update_claims_view_from_requests(claimable_outpoints, conf_height, self.best_block.height(), broadcaster, fee_estimator, logger);
3325 self.onchain_tx_handler.update_claims_view_from_matched_txn(&txn_matched, conf_height, conf_hash, self.best_block.height(), broadcaster, fee_estimator, logger);
3327 // Determine new outputs to watch by comparing against previously known outputs to watch,
3328 // updating the latter in the process.
3329 watch_outputs.retain(|&(ref txid, ref txouts)| {
3330 let idx_and_scripts = txouts.iter().map(|o| (o.0, o.1.script_pubkey.clone())).collect();
3331 self.outputs_to_watch.insert(txid.clone(), idx_and_scripts).is_none()
3335 // If we see a transaction for which we registered outputs previously,
3336 // make sure the registered scriptpubkey at the expected index match
3337 // the actual transaction output one. We failed this case before #653.
3338 for tx in &txn_matched {
3339 if let Some(outputs) = self.get_outputs_to_watch().get(&tx.txid()) {
3340 for idx_and_script in outputs.iter() {
3341 assert!((idx_and_script.0 as usize) < tx.output.len());
3342 assert_eq!(tx.output[idx_and_script.0 as usize].script_pubkey, idx_and_script.1);
3350 pub fn block_disconnected<B: Deref, F: Deref, L: Deref>(&mut self, header: &BlockHeader, height: u32, broadcaster: B, fee_estimator: F, logger: L)
3351 where B::Target: BroadcasterInterface,
3352 F::Target: FeeEstimator,
3355 log_trace!(logger, "Block {} at height {} disconnected", header.block_hash(), height);
3358 //- htlc update there as failure-trigger tx (revoked commitment tx, non-revoked commitment tx, HTLC-timeout tx) has been disconnected
3359 //- maturing spendable output has transaction paying us has been disconnected
3360 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| entry.height < height);
3362 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(fee_estimator);
3363 self.onchain_tx_handler.block_disconnected(height, broadcaster, &bounded_fee_estimator, logger);
3365 self.best_block = BestBlock::new(header.prev_blockhash, height - 1);
3368 fn transaction_unconfirmed<B: Deref, F: Deref, L: Deref>(
3372 fee_estimator: &LowerBoundedFeeEstimator<F>,
3375 B::Target: BroadcasterInterface,
3376 F::Target: FeeEstimator,
3379 let mut removed_height = None;
3380 for entry in self.onchain_events_awaiting_threshold_conf.iter() {
3381 if entry.txid == *txid {
3382 removed_height = Some(entry.height);
3387 if let Some(removed_height) = removed_height {
3388 log_info!(logger, "transaction_unconfirmed of txid {} implies height {} was reorg'd out", txid, removed_height);
3389 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| if entry.height >= removed_height {
3390 log_info!(logger, "Transaction {} reorg'd out", entry.txid);
3395 debug_assert!(!self.onchain_events_awaiting_threshold_conf.iter().any(|ref entry| entry.txid == *txid));
3397 self.onchain_tx_handler.transaction_unconfirmed(txid, broadcaster, fee_estimator, logger);
3400 /// Filters a block's `txdata` for transactions spending watched outputs or for any child
3401 /// transactions thereof.
3402 fn filter_block<'a>(&self, txdata: &TransactionData<'a>) -> Vec<&'a Transaction> {
3403 let mut matched_txn = HashSet::new();
3404 txdata.iter().filter(|&&(_, tx)| {
3405 let mut matches = self.spends_watched_output(tx);
3406 for input in tx.input.iter() {
3407 if matches { break; }
3408 if matched_txn.contains(&input.previous_output.txid) {
3413 matched_txn.insert(tx.txid());
3416 }).map(|(_, tx)| *tx).collect()
3419 /// Checks if a given transaction spends any watched outputs.
3420 fn spends_watched_output(&self, tx: &Transaction) -> bool {
3421 for input in tx.input.iter() {
3422 if let Some(outputs) = self.get_outputs_to_watch().get(&input.previous_output.txid) {
3423 for (idx, _script_pubkey) in outputs.iter() {
3424 if *idx == input.previous_output.vout {
3427 // If the expected script is a known type, check that the witness
3428 // appears to be spending the correct type (ie that the match would
3429 // actually succeed in BIP 158/159-style filters).
3430 if _script_pubkey.is_v0_p2wsh() {
3431 if input.witness.last().unwrap().to_vec() == deliberately_bogus_accepted_htlc_witness_program() {
3432 // In at least one test we use a deliberately bogus witness
3433 // script which hit an old panic. Thus, we check for that here
3434 // and avoid the assert if its the expected bogus script.
3438 assert_eq!(&bitcoin::Address::p2wsh(&Script::from(input.witness.last().unwrap().to_vec()), bitcoin::Network::Bitcoin).script_pubkey(), _script_pubkey);
3439 } else if _script_pubkey.is_v0_p2wpkh() {
3440 assert_eq!(&bitcoin::Address::p2wpkh(&bitcoin::PublicKey::from_slice(&input.witness.last().unwrap()).unwrap(), bitcoin::Network::Bitcoin).unwrap().script_pubkey(), _script_pubkey);
3441 } else { panic!(); }
3452 fn should_broadcast_holder_commitment_txn<L: Deref>(&self, logger: &L) -> bool where L::Target: Logger {
3453 // There's no need to broadcast our commitment transaction if we've seen one confirmed (even
3454 // with 1 confirmation) as it'll be rejected as duplicate/conflicting.
3455 if self.funding_spend_confirmed.is_some() ||
3456 self.onchain_events_awaiting_threshold_conf.iter().find(|event| match event.event {
3457 OnchainEvent::FundingSpendConfirmation { .. } => true,
3463 // We need to consider all HTLCs which are:
3464 // * in any unrevoked counterparty commitment transaction, as they could broadcast said
3465 // transactions and we'd end up in a race, or
3466 // * are in our latest holder commitment transaction, as this is the thing we will
3467 // broadcast if we go on-chain.
3468 // Note that we consider HTLCs which were below dust threshold here - while they don't
3469 // strictly imply that we need to fail the channel, we need to go ahead and fail them back
3470 // to the source, and if we don't fail the channel we will have to ensure that the next
3471 // updates that peer sends us are update_fails, failing the channel if not. It's probably
3472 // easier to just fail the channel as this case should be rare enough anyway.
3473 let height = self.best_block.height();
3474 macro_rules! scan_commitment {
3475 ($htlcs: expr, $holder_tx: expr) => {
3476 for ref htlc in $htlcs {
3477 // For inbound HTLCs which we know the preimage for, we have to ensure we hit the
3478 // chain with enough room to claim the HTLC without our counterparty being able to
3479 // time out the HTLC first.
3480 // For outbound HTLCs which our counterparty hasn't failed/claimed, our primary
3481 // concern is being able to claim the corresponding inbound HTLC (on another
3482 // channel) before it expires. In fact, we don't even really care if our
3483 // counterparty here claims such an outbound HTLC after it expired as long as we
3484 // can still claim the corresponding HTLC. Thus, to avoid needlessly hitting the
3485 // chain when our counterparty is waiting for expiration to off-chain fail an HTLC
3486 // we give ourselves a few blocks of headroom after expiration before going
3487 // on-chain for an expired HTLC.
3488 // Note that, to avoid a potential attack whereby a node delays claiming an HTLC
3489 // from us until we've reached the point where we go on-chain with the
3490 // corresponding inbound HTLC, we must ensure that outbound HTLCs go on chain at
3491 // least CLTV_CLAIM_BUFFER blocks prior to the inbound HTLC.
3492 // aka outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS == height - CLTV_CLAIM_BUFFER
3493 // inbound_cltv == height + CLTV_CLAIM_BUFFER
3494 // outbound_cltv + LATENCY_GRACE_PERIOD_BLOCKS + CLTV_CLAIM_BUFFER <= inbound_cltv - CLTV_CLAIM_BUFFER
3495 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= inbound_cltv - outbound_cltv
3496 // CLTV_EXPIRY_DELTA <= inbound_cltv - outbound_cltv (by check in ChannelManager::decode_update_add_htlc_onion)
3497 // LATENCY_GRACE_PERIOD_BLOCKS + 2*CLTV_CLAIM_BUFFER <= CLTV_EXPIRY_DELTA
3498 // The final, above, condition is checked for statically in channelmanager
3499 // with CHECK_CLTV_EXPIRY_SANITY_2.
3500 let htlc_outbound = $holder_tx == htlc.offered;
3501 if ( htlc_outbound && htlc.cltv_expiry + LATENCY_GRACE_PERIOD_BLOCKS <= height) ||
3502 (!htlc_outbound && htlc.cltv_expiry <= height + CLTV_CLAIM_BUFFER && self.payment_preimages.contains_key(&htlc.payment_hash)) {
3503 log_info!(logger, "Force-closing channel due to {} HTLC timeout, HTLC expiry is {}", if htlc_outbound { "outbound" } else { "inbound "}, htlc.cltv_expiry);
3510 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, _)| a), true);
3512 if let Some(ref txid) = self.current_counterparty_commitment_txid {
3513 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3514 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3517 if let Some(ref txid) = self.prev_counterparty_commitment_txid {
3518 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(txid) {
3519 scan_commitment!(htlc_outputs.iter().map(|&(ref a, _)| a), false);
3526 /// Check if any transaction broadcasted is resolving HTLC output by a success or timeout on a holder
3527 /// or counterparty commitment tx, if so send back the source, preimage if found and payment_hash of resolved HTLC
3528 fn is_resolving_htlc_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3529 'outer_loop: for input in &tx.input {
3530 let mut payment_data = None;
3531 let htlc_claim = HTLCClaim::from_witness(&input.witness);
3532 let revocation_sig_claim = htlc_claim == Some(HTLCClaim::Revocation);
3533 let accepted_preimage_claim = htlc_claim == Some(HTLCClaim::AcceptedPreimage);
3534 #[cfg(not(fuzzing))]
3535 let accepted_timeout_claim = htlc_claim == Some(HTLCClaim::AcceptedTimeout);
3536 let offered_preimage_claim = htlc_claim == Some(HTLCClaim::OfferedPreimage);
3537 #[cfg(not(fuzzing))]
3538 let offered_timeout_claim = htlc_claim == Some(HTLCClaim::OfferedTimeout);
3540 let mut payment_preimage = PaymentPreimage([0; 32]);
3541 if offered_preimage_claim || accepted_preimage_claim {
3542 payment_preimage.0.copy_from_slice(input.witness.second_to_last().unwrap());
3545 macro_rules! log_claim {
3546 ($tx_info: expr, $holder_tx: expr, $htlc: expr, $source_avail: expr) => {
3547 let outbound_htlc = $holder_tx == $htlc.offered;
3548 // HTLCs must either be claimed by a matching script type or through the
3550 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3551 debug_assert!(!$htlc.offered || offered_preimage_claim || offered_timeout_claim || revocation_sig_claim);
3552 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3553 debug_assert!($htlc.offered || accepted_preimage_claim || accepted_timeout_claim || revocation_sig_claim);
3554 // Further, only exactly one of the possible spend paths should have been
3555 // matched by any HTLC spend:
3556 #[cfg(not(fuzzing))] // Note that the fuzzer is not bound by pesky things like "signatures"
3557 debug_assert_eq!(accepted_preimage_claim as u8 + accepted_timeout_claim as u8 +
3558 offered_preimage_claim as u8 + offered_timeout_claim as u8 +
3559 revocation_sig_claim as u8, 1);
3560 if ($holder_tx && revocation_sig_claim) ||
3561 (outbound_htlc && !$source_avail && (accepted_preimage_claim || offered_preimage_claim)) {
3562 log_error!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}!",
3563 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3564 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3565 if revocation_sig_claim { "revocation sig" } else { "preimage claim after we'd passed the HTLC resolution back. We can likely claim the HTLC output with a revocation claim" });
3567 log_info!(logger, "Input spending {} ({}:{}) in {} resolves {} HTLC with payment hash {} with {}",
3568 $tx_info, input.previous_output.txid, input.previous_output.vout, tx.txid(),
3569 if outbound_htlc { "outbound" } else { "inbound" }, log_bytes!($htlc.payment_hash.0),
3570 if revocation_sig_claim { "revocation sig" } else if accepted_preimage_claim || offered_preimage_claim { "preimage" } else { "timeout" });
3575 macro_rules! check_htlc_valid_counterparty {
3576 ($counterparty_txid: expr, $htlc_output: expr) => {
3577 if let Some(txid) = $counterparty_txid {
3578 for &(ref pending_htlc, ref pending_source) in self.counterparty_claimable_outpoints.get(&txid).unwrap() {
3579 if pending_htlc.payment_hash == $htlc_output.payment_hash && pending_htlc.amount_msat == $htlc_output.amount_msat {
3580 if let &Some(ref source) = pending_source {
3581 log_claim!("revoked counterparty commitment tx", false, pending_htlc, true);
3582 payment_data = Some(((**source).clone(), $htlc_output.payment_hash, $htlc_output.amount_msat));
3591 macro_rules! scan_commitment {
3592 ($htlcs: expr, $tx_info: expr, $holder_tx: expr) => {
3593 for (ref htlc_output, source_option) in $htlcs {
3594 if Some(input.previous_output.vout) == htlc_output.transaction_output_index {
3595 if let Some(ref source) = source_option {
3596 log_claim!($tx_info, $holder_tx, htlc_output, true);
3597 // We have a resolution of an HTLC either from one of our latest
3598 // holder commitment transactions or an unrevoked counterparty commitment
3599 // transaction. This implies we either learned a preimage, the HTLC
3600 // has timed out, or we screwed up. In any case, we should now
3601 // resolve the source HTLC with the original sender.
3602 payment_data = Some(((*source).clone(), htlc_output.payment_hash, htlc_output.amount_msat));
3603 } else if !$holder_tx {
3604 check_htlc_valid_counterparty!(self.current_counterparty_commitment_txid, htlc_output);
3605 if payment_data.is_none() {
3606 check_htlc_valid_counterparty!(self.prev_counterparty_commitment_txid, htlc_output);
3609 if payment_data.is_none() {
3610 log_claim!($tx_info, $holder_tx, htlc_output, false);
3611 let outbound_htlc = $holder_tx == htlc_output.offered;
3612 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3613 txid: tx.txid(), height, block_hash: Some(*block_hash), transaction: Some(tx.clone()),
3614 event: OnchainEvent::HTLCSpendConfirmation {
3615 commitment_tx_output_idx: input.previous_output.vout,
3616 preimage: if accepted_preimage_claim || offered_preimage_claim {
3617 Some(payment_preimage) } else { None },
3618 // If this is a payment to us (ie !outbound_htlc), wait for
3619 // the CSV delay before dropping the HTLC from claimable
3620 // balance if the claim was an HTLC-Success transaction (ie
3621 // accepted_preimage_claim).
3622 on_to_local_output_csv: if accepted_preimage_claim && !outbound_htlc {
3623 Some(self.on_holder_tx_csv) } else { None },
3626 continue 'outer_loop;
3633 if input.previous_output.txid == self.current_holder_commitment_tx.txid {
3634 scan_commitment!(self.current_holder_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3635 "our latest holder commitment tx", true);
3637 if let Some(ref prev_holder_signed_commitment_tx) = self.prev_holder_signed_commitment_tx {
3638 if input.previous_output.txid == prev_holder_signed_commitment_tx.txid {
3639 scan_commitment!(prev_holder_signed_commitment_tx.htlc_outputs.iter().map(|&(ref a, _, ref b)| (a, b.as_ref())),
3640 "our previous holder commitment tx", true);
3643 if let Some(ref htlc_outputs) = self.counterparty_claimable_outpoints.get(&input.previous_output.txid) {
3644 scan_commitment!(htlc_outputs.iter().map(|&(ref a, ref b)| (a, (b.as_ref().clone()).map(|boxed| &**boxed))),
3645 "counterparty commitment tx", false);
3648 // Check that scan_commitment, above, decided there is some source worth relaying an
3649 // HTLC resolution backwards to and figure out whether we learned a preimage from it.
3650 if let Some((source, payment_hash, amount_msat)) = payment_data {
3651 if accepted_preimage_claim {
3652 if !self.pending_monitor_events.iter().any(
3653 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update { upd.source == source } else { false }) {
3654 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3657 block_hash: Some(*block_hash),
3658 transaction: Some(tx.clone()),
3659 event: OnchainEvent::HTLCSpendConfirmation {
3660 commitment_tx_output_idx: input.previous_output.vout,
3661 preimage: Some(payment_preimage),
3662 on_to_local_output_csv: None,
3665 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3667 payment_preimage: Some(payment_preimage),
3669 htlc_value_satoshis: Some(amount_msat / 1000),
3672 } else if offered_preimage_claim {
3673 if !self.pending_monitor_events.iter().any(
3674 |update| if let &MonitorEvent::HTLCEvent(ref upd) = update {
3675 upd.source == source
3677 self.onchain_events_awaiting_threshold_conf.push(OnchainEventEntry {
3679 transaction: Some(tx.clone()),
3681 block_hash: Some(*block_hash),
3682 event: OnchainEvent::HTLCSpendConfirmation {
3683 commitment_tx_output_idx: input.previous_output.vout,
3684 preimage: Some(payment_preimage),
3685 on_to_local_output_csv: None,
3688 self.pending_monitor_events.push(MonitorEvent::HTLCEvent(HTLCUpdate {
3690 payment_preimage: Some(payment_preimage),
3692 htlc_value_satoshis: Some(amount_msat / 1000),
3696 self.onchain_events_awaiting_threshold_conf.retain(|ref entry| {
3697 if entry.height != height { return true; }
3699 OnchainEvent::HTLCUpdate { source: ref htlc_source, .. } => {
3700 *htlc_source != source
3705 let entry = OnchainEventEntry {
3707 transaction: Some(tx.clone()),
3709 block_hash: Some(*block_hash),
3710 event: OnchainEvent::HTLCUpdate {
3711 source, payment_hash,
3712 htlc_value_satoshis: Some(amount_msat / 1000),
3713 commitment_tx_output_idx: Some(input.previous_output.vout),
3716 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());
3717 self.onchain_events_awaiting_threshold_conf.push(entry);
3723 /// Check if any transaction broadcasted is paying fund back to some address we can assume to own
3724 fn is_paying_spendable_output<L: Deref>(&mut self, tx: &Transaction, height: u32, block_hash: &BlockHash, logger: &L) where L::Target: Logger {
3725 let mut spendable_output = None;
3726 for (i, outp) in tx.output.iter().enumerate() { // There is max one spendable output for any channel tx, including ones generated by us
3727 if i > ::core::u16::MAX as usize {
3728 // While it is possible that an output exists on chain which is greater than the
3729 // 2^16th output in a given transaction, this is only possible if the output is not
3730 // in a lightning transaction and was instead placed there by some third party who
3731 // wishes to give us money for no reason.
3732 // Namely, any lightning transactions which we pre-sign will never have anywhere
3733 // near 2^16 outputs both because such transactions must have ~2^16 outputs who's
3734 // scripts are not longer than one byte in length and because they are inherently
3735 // non-standard due to their size.
3736 // Thus, it is completely safe to ignore such outputs, and while it may result in
3737 // us ignoring non-lightning fund to us, that is only possible if someone fills
3738 // nearly a full block with garbage just to hit this case.
3741 if outp.script_pubkey == self.destination_script {
3742 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3743 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3744 output: outp.clone(),
3748 if let Some(ref broadcasted_holder_revokable_script) = self.broadcasted_holder_revokable_script {
3749 if broadcasted_holder_revokable_script.0 == outp.script_pubkey {
3750 spendable_output = Some(SpendableOutputDescriptor::DelayedPaymentOutput(DelayedPaymentOutputDescriptor {
3751 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3752 per_commitment_point: broadcasted_holder_revokable_script.1,
3753 to_self_delay: self.on_holder_tx_csv,
3754 output: outp.clone(),
3755 revocation_pubkey: broadcasted_holder_revokable_script.2.clone(),
3756 channel_keys_id: self.channel_keys_id,
3757 channel_value_satoshis: self.channel_value_satoshis,
3762 if self.counterparty_payment_script == outp.script_pubkey {
3763 spendable_output = Some(SpendableOutputDescriptor::StaticPaymentOutput(StaticPaymentOutputDescriptor {
3764 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3765 output: outp.clone(),
3766 channel_keys_id: self.channel_keys_id,
3767 channel_value_satoshis: self.channel_value_satoshis,
3771 if self.shutdown_script.as_ref() == Some(&outp.script_pubkey) {
3772 spendable_output = Some(SpendableOutputDescriptor::StaticOutput {
3773 outpoint: OutPoint { txid: tx.txid(), index: i as u16 },
3774 output: outp.clone(),
3779 if let Some(spendable_output) = spendable_output {
3780 let entry = OnchainEventEntry {
3782 transaction: Some(tx.clone()),
3784 block_hash: Some(*block_hash),
3785 event: OnchainEvent::MaturingOutput { descriptor: spendable_output.clone() },
3787 log_info!(logger, "Received spendable output {}, spendable at height {}", log_spendable!(spendable_output), entry.confirmation_threshold());
3788 self.onchain_events_awaiting_threshold_conf.push(entry);
3793 impl<Signer: WriteableEcdsaChannelSigner, T: Deref, F: Deref, L: Deref> chain::Listen for (ChannelMonitor<Signer>, T, F, L)
3795 T::Target: BroadcasterInterface,
3796 F::Target: FeeEstimator,
3799 fn filtered_block_connected(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3800 self.0.block_connected(header, txdata, height, &*self.1, &*self.2, &*self.3);
3803 fn block_disconnected(&self, header: &BlockHeader, height: u32) {
3804 self.0.block_disconnected(header, height, &*self.1, &*self.2, &*self.3);
3808 impl<Signer: WriteableEcdsaChannelSigner, M, T: Deref, F: Deref, L: Deref> chain::Confirm for (M, T, F, L)
3810 M: Deref<Target = ChannelMonitor<Signer>>,
3811 T::Target: BroadcasterInterface,
3812 F::Target: FeeEstimator,
3815 fn transactions_confirmed(&self, header: &BlockHeader, txdata: &TransactionData, height: u32) {
3816 self.0.transactions_confirmed(header, txdata, height, &*self.1, &*self.2, &*self.3);
3819 fn transaction_unconfirmed(&self, txid: &Txid) {
3820 self.0.transaction_unconfirmed(txid, &*self.1, &*self.2, &*self.3);
3823 fn best_block_updated(&self, header: &BlockHeader, height: u32) {
3824 self.0.best_block_updated(header, height, &*self.1, &*self.2, &*self.3);
3827 fn get_relevant_txids(&self) -> Vec<(Txid, Option<BlockHash>)> {
3828 self.0.get_relevant_txids()
3832 const MAX_ALLOC_SIZE: usize = 64*1024;
3834 impl<'a, 'b, ES: EntropySource, SP: SignerProvider> ReadableArgs<(&'a ES, &'b SP)>
3835 for (BlockHash, ChannelMonitor<SP::Signer>) {
3836 fn read<R: io::Read>(reader: &mut R, args: (&'a ES, &'b SP)) -> Result<Self, DecodeError> {
3837 macro_rules! unwrap_obj {
3841 Err(_) => return Err(DecodeError::InvalidValue),
3846 let (entropy_source, signer_provider) = args;
3848 let _ver = read_ver_prefix!(reader, SERIALIZATION_VERSION);
3850 let latest_update_id: u64 = Readable::read(reader)?;
3851 let commitment_transaction_number_obscure_factor = <U48 as Readable>::read(reader)?.0;
3853 let destination_script = Readable::read(reader)?;
3854 let broadcasted_holder_revokable_script = match <u8 as Readable>::read(reader)? {
3856 let revokable_address = Readable::read(reader)?;
3857 let per_commitment_point = Readable::read(reader)?;
3858 let revokable_script = Readable::read(reader)?;
3859 Some((revokable_address, per_commitment_point, revokable_script))
3862 _ => return Err(DecodeError::InvalidValue),
3864 let counterparty_payment_script = Readable::read(reader)?;
3865 let shutdown_script = {
3866 let script = <Script as Readable>::read(reader)?;
3867 if script.is_empty() { None } else { Some(script) }
3870 let channel_keys_id = Readable::read(reader)?;
3871 let holder_revocation_basepoint = Readable::read(reader)?;
3872 // Technically this can fail and serialize fail a round-trip, but only for serialization of
3873 // barely-init'd ChannelMonitors that we can't do anything with.
3874 let outpoint = OutPoint {
3875 txid: Readable::read(reader)?,
3876 index: Readable::read(reader)?,
3878 let funding_info = (outpoint, Readable::read(reader)?);
3879 let current_counterparty_commitment_txid = Readable::read(reader)?;
3880 let prev_counterparty_commitment_txid = Readable::read(reader)?;
3882 let counterparty_commitment_params = Readable::read(reader)?;
3883 let funding_redeemscript = Readable::read(reader)?;
3884 let channel_value_satoshis = Readable::read(reader)?;
3886 let their_cur_per_commitment_points = {
3887 let first_idx = <U48 as Readable>::read(reader)?.0;
3891 let first_point = Readable::read(reader)?;
3892 let second_point_slice: [u8; 33] = Readable::read(reader)?;
3893 if second_point_slice[0..32] == [0; 32] && second_point_slice[32] == 0 {
3894 Some((first_idx, first_point, None))
3896 Some((first_idx, first_point, Some(unwrap_obj!(PublicKey::from_slice(&second_point_slice)))))
3901 let on_holder_tx_csv: u16 = Readable::read(reader)?;
3903 let commitment_secrets = Readable::read(reader)?;
3905 macro_rules! read_htlc_in_commitment {
3908 let offered: bool = Readable::read(reader)?;
3909 let amount_msat: u64 = Readable::read(reader)?;
3910 let cltv_expiry: u32 = Readable::read(reader)?;
3911 let payment_hash: PaymentHash = Readable::read(reader)?;
3912 let transaction_output_index: Option<u32> = Readable::read(reader)?;
3914 HTLCOutputInCommitment {
3915 offered, amount_msat, cltv_expiry, payment_hash, transaction_output_index
3921 let counterparty_claimable_outpoints_len: u64 = Readable::read(reader)?;
3922 let mut counterparty_claimable_outpoints = HashMap::with_capacity(cmp::min(counterparty_claimable_outpoints_len as usize, MAX_ALLOC_SIZE / 64));
3923 for _ in 0..counterparty_claimable_outpoints_len {
3924 let txid: Txid = Readable::read(reader)?;
3925 let htlcs_count: u64 = Readable::read(reader)?;
3926 let mut htlcs = Vec::with_capacity(cmp::min(htlcs_count as usize, MAX_ALLOC_SIZE / 32));
3927 for _ in 0..htlcs_count {
3928 htlcs.push((read_htlc_in_commitment!(), <Option<HTLCSource> as Readable>::read(reader)?.map(|o: HTLCSource| Box::new(o))));
3930 if let Some(_) = counterparty_claimable_outpoints.insert(txid, htlcs) {
3931 return Err(DecodeError::InvalidValue);
3935 let counterparty_commitment_txn_on_chain_len: u64 = Readable::read(reader)?;
3936 let mut counterparty_commitment_txn_on_chain = HashMap::with_capacity(cmp::min(counterparty_commitment_txn_on_chain_len as usize, MAX_ALLOC_SIZE / 32));
3937 for _ in 0..counterparty_commitment_txn_on_chain_len {
3938 let txid: Txid = Readable::read(reader)?;
3939 let commitment_number = <U48 as Readable>::read(reader)?.0;
3940 if let Some(_) = counterparty_commitment_txn_on_chain.insert(txid, commitment_number) {
3941 return Err(DecodeError::InvalidValue);
3945 let counterparty_hash_commitment_number_len: u64 = Readable::read(reader)?;
3946 let mut counterparty_hash_commitment_number = HashMap::with_capacity(cmp::min(counterparty_hash_commitment_number_len as usize, MAX_ALLOC_SIZE / 32));
3947 for _ in 0..counterparty_hash_commitment_number_len {
3948 let payment_hash: PaymentHash = Readable::read(reader)?;
3949 let commitment_number = <U48 as Readable>::read(reader)?.0;
3950 if let Some(_) = counterparty_hash_commitment_number.insert(payment_hash, commitment_number) {
3951 return Err(DecodeError::InvalidValue);
3955 let mut prev_holder_signed_commitment_tx: Option<HolderSignedTx> =
3956 match <u8 as Readable>::read(reader)? {
3959 Some(Readable::read(reader)?)
3961 _ => return Err(DecodeError::InvalidValue),
3963 let mut current_holder_commitment_tx: HolderSignedTx = Readable::read(reader)?;
3965 let current_counterparty_commitment_number = <U48 as Readable>::read(reader)?.0;
3966 let current_holder_commitment_number = <U48 as Readable>::read(reader)?.0;
3968 let payment_preimages_len: u64 = Readable::read(reader)?;
3969 let mut payment_preimages = HashMap::with_capacity(cmp::min(payment_preimages_len as usize, MAX_ALLOC_SIZE / 32));
3970 for _ in 0..payment_preimages_len {
3971 let preimage: PaymentPreimage = Readable::read(reader)?;
3972 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
3973 if let Some(_) = payment_preimages.insert(hash, preimage) {
3974 return Err(DecodeError::InvalidValue);
3978 let pending_monitor_events_len: u64 = Readable::read(reader)?;
3979 let mut pending_monitor_events = Some(
3980 Vec::with_capacity(cmp::min(pending_monitor_events_len as usize, MAX_ALLOC_SIZE / (32 + 8*3))));
3981 for _ in 0..pending_monitor_events_len {
3982 let ev = match <u8 as Readable>::read(reader)? {
3983 0 => MonitorEvent::HTLCEvent(Readable::read(reader)?),
3984 1 => MonitorEvent::CommitmentTxConfirmed(funding_info.0),
3985 _ => return Err(DecodeError::InvalidValue)
3987 pending_monitor_events.as_mut().unwrap().push(ev);
3990 let pending_events_len: u64 = Readable::read(reader)?;
3991 let mut pending_events = Vec::with_capacity(cmp::min(pending_events_len as usize, MAX_ALLOC_SIZE / mem::size_of::<Event>()));
3992 for _ in 0..pending_events_len {
3993 if let Some(event) = MaybeReadable::read(reader)? {
3994 pending_events.push(event);
3998 let best_block = BestBlock::new(Readable::read(reader)?, Readable::read(reader)?);
4000 let waiting_threshold_conf_len: u64 = Readable::read(reader)?;
4001 let mut onchain_events_awaiting_threshold_conf = Vec::with_capacity(cmp::min(waiting_threshold_conf_len as usize, MAX_ALLOC_SIZE / 128));
4002 for _ in 0..waiting_threshold_conf_len {
4003 if let Some(val) = MaybeReadable::read(reader)? {
4004 onchain_events_awaiting_threshold_conf.push(val);
4008 let outputs_to_watch_len: u64 = Readable::read(reader)?;
4009 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>>())));
4010 for _ in 0..outputs_to_watch_len {
4011 let txid = Readable::read(reader)?;
4012 let outputs_len: u64 = Readable::read(reader)?;
4013 let mut outputs = Vec::with_capacity(cmp::min(outputs_len as usize, MAX_ALLOC_SIZE / (mem::size_of::<u32>() + mem::size_of::<Script>())));
4014 for _ in 0..outputs_len {
4015 outputs.push((Readable::read(reader)?, Readable::read(reader)?));
4017 if let Some(_) = outputs_to_watch.insert(txid, outputs) {
4018 return Err(DecodeError::InvalidValue);
4021 let onchain_tx_handler: OnchainTxHandler<SP::Signer> = ReadableArgs::read(
4022 reader, (entropy_source, signer_provider, channel_value_satoshis, channel_keys_id)
4025 let lockdown_from_offchain = Readable::read(reader)?;
4026 let holder_tx_signed = Readable::read(reader)?;
4028 if let Some(prev_commitment_tx) = prev_holder_signed_commitment_tx.as_mut() {
4029 let prev_holder_value = onchain_tx_handler.get_prev_holder_commitment_to_self_value();
4030 if prev_holder_value.is_none() { return Err(DecodeError::InvalidValue); }
4031 if prev_commitment_tx.to_self_value_sat == u64::max_value() {
4032 prev_commitment_tx.to_self_value_sat = prev_holder_value.unwrap();
4033 } else if prev_commitment_tx.to_self_value_sat != prev_holder_value.unwrap() {
4034 return Err(DecodeError::InvalidValue);
4038 let cur_holder_value = onchain_tx_handler.get_cur_holder_commitment_to_self_value();
4039 if current_holder_commitment_tx.to_self_value_sat == u64::max_value() {
4040 current_holder_commitment_tx.to_self_value_sat = cur_holder_value;
4041 } else if current_holder_commitment_tx.to_self_value_sat != cur_holder_value {
4042 return Err(DecodeError::InvalidValue);
4045 let mut funding_spend_confirmed = None;
4046 let mut htlcs_resolved_on_chain = Some(Vec::new());
4047 let mut funding_spend_seen = Some(false);
4048 let mut counterparty_node_id = None;
4049 let mut confirmed_commitment_tx_counterparty_output = None;
4050 let mut spendable_txids_confirmed = Some(Vec::new());
4051 let mut counterparty_fulfilled_htlcs = Some(HashMap::new());
4052 read_tlv_fields!(reader, {
4053 (1, funding_spend_confirmed, option),
4054 (3, htlcs_resolved_on_chain, optional_vec),
4055 (5, pending_monitor_events, optional_vec),
4056 (7, funding_spend_seen, option),
4057 (9, counterparty_node_id, option),
4058 (11, confirmed_commitment_tx_counterparty_output, option),
4059 (13, spendable_txids_confirmed, optional_vec),
4060 (15, counterparty_fulfilled_htlcs, option),
4063 Ok((best_block.block_hash(), ChannelMonitor::from_impl(ChannelMonitorImpl {
4065 commitment_transaction_number_obscure_factor,
4068 broadcasted_holder_revokable_script,
4069 counterparty_payment_script,
4073 holder_revocation_basepoint,
4075 current_counterparty_commitment_txid,
4076 prev_counterparty_commitment_txid,
4078 counterparty_commitment_params,
4079 funding_redeemscript,
4080 channel_value_satoshis,
4081 their_cur_per_commitment_points,
4086 counterparty_claimable_outpoints,
4087 counterparty_commitment_txn_on_chain,
4088 counterparty_hash_commitment_number,
4089 counterparty_fulfilled_htlcs: counterparty_fulfilled_htlcs.unwrap(),
4091 prev_holder_signed_commitment_tx,
4092 current_holder_commitment_tx,
4093 current_counterparty_commitment_number,
4094 current_holder_commitment_number,
4097 pending_monitor_events: pending_monitor_events.unwrap(),
4100 onchain_events_awaiting_threshold_conf,
4105 lockdown_from_offchain,
4107 funding_spend_seen: funding_spend_seen.unwrap(),
4108 funding_spend_confirmed,
4109 confirmed_commitment_tx_counterparty_output,
4110 htlcs_resolved_on_chain: htlcs_resolved_on_chain.unwrap(),
4111 spendable_txids_confirmed: spendable_txids_confirmed.unwrap(),
4114 counterparty_node_id,
4121 use bitcoin::blockdata::script::{Script, Builder};
4122 use bitcoin::blockdata::opcodes;
4123 use bitcoin::blockdata::transaction::{Transaction, TxIn, TxOut, EcdsaSighashType};
4124 use bitcoin::blockdata::transaction::OutPoint as BitcoinOutPoint;
4125 use bitcoin::util::sighash;
4126 use bitcoin::hashes::Hash;
4127 use bitcoin::hashes::sha256::Hash as Sha256;
4128 use bitcoin::hashes::hex::FromHex;
4129 use bitcoin::hash_types::{BlockHash, Txid};
4130 use bitcoin::network::constants::Network;
4131 use bitcoin::secp256k1::{SecretKey,PublicKey};
4132 use bitcoin::secp256k1::Secp256k1;
4136 use crate::chain::chaininterface::LowerBoundedFeeEstimator;
4138 use super::ChannelMonitorUpdateStep;
4139 use crate::{check_added_monitors, check_closed_broadcast, check_closed_event, check_spends, get_local_commitment_txn, get_monitor, get_route_and_payment_hash, unwrap_send_err};
4140 use crate::chain::{BestBlock, Confirm};
4141 use crate::chain::channelmonitor::ChannelMonitor;
4142 use crate::chain::package::{weight_offered_htlc, weight_received_htlc, weight_revoked_offered_htlc, weight_revoked_received_htlc, WEIGHT_REVOKED_OUTPUT};
4143 use crate::chain::transaction::OutPoint;
4144 use crate::sign::InMemorySigner;
4145 use crate::events::ClosureReason;
4146 use crate::ln::{PaymentPreimage, PaymentHash};
4147 use crate::ln::chan_utils;
4148 use crate::ln::chan_utils::{HTLCOutputInCommitment, ChannelPublicKeys, ChannelTransactionParameters, HolderCommitmentTransaction, CounterpartyChannelTransactionParameters};
4149 use crate::ln::channelmanager::{PaymentSendFailure, PaymentId, RecipientOnionFields};
4150 use crate::ln::functional_test_utils::*;
4151 use crate::ln::script::ShutdownScript;
4152 use crate::util::errors::APIError;
4153 use crate::util::test_utils::{TestLogger, TestBroadcaster, TestFeeEstimator};
4154 use crate::util::ser::{ReadableArgs, Writeable};
4155 use crate::sync::{Arc, Mutex};
4157 use bitcoin::{PackedLockTime, Sequence, Witness};
4158 use crate::ln::features::ChannelTypeFeatures;
4159 use crate::prelude::*;
4161 fn do_test_funding_spend_refuses_updates(use_local_txn: bool) {
4162 // Previously, monitor updates were allowed freely even after a funding-spend transaction
4163 // confirmed. This would allow a race condition where we could receive a payment (including
4164 // the counterparty revoking their broadcasted state!) and accept it without recourse as
4165 // long as the ChannelMonitor receives the block first, the full commitment update dance
4166 // occurs after the block is connected, and before the ChannelManager receives the block.
4167 // Obviously this is an incredibly contrived race given the counterparty would be risking
4168 // their full channel balance for it, but its worth fixing nonetheless as it makes the
4169 // potential ChannelMonitor states simpler to reason about.
4171 // This test checks said behavior, as well as ensuring a ChannelMonitorUpdate with multiple
4172 // updates is handled correctly in such conditions.
4173 let chanmon_cfgs = create_chanmon_cfgs(3);
4174 let node_cfgs = create_node_cfgs(3, &chanmon_cfgs);
4175 let node_chanmgrs = create_node_chanmgrs(3, &node_cfgs, &[None, None, None]);
4176 let nodes = create_network(3, &node_cfgs, &node_chanmgrs);
4177 let channel = create_announced_chan_between_nodes(&nodes, 0, 1);
4178 create_announced_chan_between_nodes(&nodes, 1, 2);
4180 // Rebalance somewhat
4181 send_payment(&nodes[0], &[&nodes[1]], 10_000_000);
4183 // First route two payments for testing at the end
4184 let payment_preimage_1 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4185 let payment_preimage_2 = route_payment(&nodes[0], &[&nodes[1], &nodes[2]], 1_000_000).0;
4187 let local_txn = get_local_commitment_txn!(nodes[1], channel.2);
4188 assert_eq!(local_txn.len(), 1);
4189 let remote_txn = get_local_commitment_txn!(nodes[0], channel.2);
4190 assert_eq!(remote_txn.len(), 3); // Commitment and two HTLC-Timeouts
4191 check_spends!(remote_txn[1], remote_txn[0]);
4192 check_spends!(remote_txn[2], remote_txn[0]);
4193 let broadcast_tx = if use_local_txn { &local_txn[0] } else { &remote_txn[0] };
4195 // Connect a commitment transaction, but only to the ChainMonitor/ChannelMonitor. The
4196 // channel is now closed, but the ChannelManager doesn't know that yet.
4197 let new_header = create_dummy_header(nodes[0].best_block_info().0, 0);
4198 let conf_height = nodes[0].best_block_info().1 + 1;
4199 nodes[1].chain_monitor.chain_monitor.transactions_confirmed(&new_header,
4200 &[(0, broadcast_tx)], conf_height);
4202 let (_, pre_update_monitor) = <(BlockHash, ChannelMonitor<InMemorySigner>)>::read(
4203 &mut io::Cursor::new(&get_monitor!(nodes[1], channel.2).encode()),
4204 (&nodes[1].keys_manager.backing, &nodes[1].keys_manager.backing)).unwrap();
4206 // If the ChannelManager tries to update the channel, however, the ChainMonitor will pass
4207 // the update through to the ChannelMonitor which will refuse it (as the channel is closed).
4208 let (route, payment_hash, _, payment_secret) = get_route_and_payment_hash!(nodes[1], nodes[0], 100_000);
4209 unwrap_send_err!(nodes[1].node.send_payment_with_route(&route, payment_hash,
4210 RecipientOnionFields::secret_only(payment_secret), PaymentId(payment_hash.0)
4211 ), true, APIError::ChannelUnavailable { ref err },
4212 assert!(err.contains("ChannelMonitor storage failure")));
4213 check_added_monitors!(nodes[1], 2); // After the failure we generate a close-channel monitor update
4214 check_closed_broadcast!(nodes[1], true);
4215 check_closed_event!(nodes[1], 1, ClosureReason::ProcessingError { err: "ChannelMonitor storage failure".to_string() });
4217 // Build a new ChannelMonitorUpdate which contains both the failing commitment tx update
4218 // and provides the claim preimages for the two pending HTLCs. The first update generates
4219 // an error, but the point of this test is to ensure the later updates are still applied.
4220 let monitor_updates = nodes[1].chain_monitor.monitor_updates.lock().unwrap();
4221 let mut replay_update = monitor_updates.get(&channel.2).unwrap().iter().rev().skip(1).next().unwrap().clone();
4222 assert_eq!(replay_update.updates.len(), 1);
4223 if let ChannelMonitorUpdateStep::LatestCounterpartyCommitmentTXInfo { .. } = replay_update.updates[0] {
4224 } else { panic!(); }
4225 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_1 });
4226 replay_update.updates.push(ChannelMonitorUpdateStep::PaymentPreimage { payment_preimage: payment_preimage_2 });
4228 let broadcaster = TestBroadcaster::with_blocks(Arc::clone(&nodes[1].blocks));
4230 pre_update_monitor.update_monitor(&replay_update, &&broadcaster, &chanmon_cfgs[1].fee_estimator, &nodes[1].logger)
4232 // Even though we error'd on the first update, we should still have generated an HTLC claim
4234 let txn_broadcasted = broadcaster.txn_broadcasted.lock().unwrap().split_off(0);
4235 assert!(txn_broadcasted.len() >= 2);
4236 let htlc_txn = txn_broadcasted.iter().filter(|tx| {
4237 assert_eq!(tx.input.len(), 1);
4238 tx.input[0].previous_output.txid == broadcast_tx.txid()
4239 }).collect::<Vec<_>>();
4240 assert_eq!(htlc_txn.len(), 2);
4241 check_spends!(htlc_txn[0], broadcast_tx);
4242 check_spends!(htlc_txn[1], broadcast_tx);
4245 fn test_funding_spend_refuses_updates() {
4246 do_test_funding_spend_refuses_updates(true);
4247 do_test_funding_spend_refuses_updates(false);
4251 fn test_prune_preimages() {
4252 let secp_ctx = Secp256k1::new();
4253 let logger = Arc::new(TestLogger::new());
4254 let broadcaster = Arc::new(TestBroadcaster::new(Network::Testnet));
4255 let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
4257 let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4259 let mut preimages = Vec::new();
4262 let preimage = PaymentPreimage([i; 32]);
4263 let hash = PaymentHash(Sha256::hash(&preimage.0[..]).into_inner());
4264 preimages.push((preimage, hash));
4268 macro_rules! preimages_slice_to_htlcs {
4269 ($preimages_slice: expr) => {
4271 let mut res = Vec::new();
4272 for (idx, preimage) in $preimages_slice.iter().enumerate() {
4273 res.push((HTLCOutputInCommitment {
4277 payment_hash: preimage.1.clone(),
4278 transaction_output_index: Some(idx as u32),
4285 macro_rules! preimages_slice_to_htlc_outputs {
4286 ($preimages_slice: expr) => {
4287 preimages_slice_to_htlcs!($preimages_slice).into_iter().map(|(htlc, _)| (htlc, None)).collect()
4290 let dummy_sig = crate::util::crypto::sign(&secp_ctx,
4291 &bitcoin::secp256k1::Message::from_slice(&[42; 32]).unwrap(),
4292 &SecretKey::from_slice(&[42; 32]).unwrap());
4294 macro_rules! test_preimages_exist {
4295 ($preimages_slice: expr, $monitor: expr) => {
4296 for preimage in $preimages_slice {
4297 assert!($monitor.inner.lock().unwrap().payment_preimages.contains_key(&preimage.1));
4302 let keys = InMemorySigner::new(
4304 SecretKey::from_slice(&[41; 32]).unwrap(),
4305 SecretKey::from_slice(&[41; 32]).unwrap(),
4306 SecretKey::from_slice(&[41; 32]).unwrap(),
4307 SecretKey::from_slice(&[41; 32]).unwrap(),
4308 SecretKey::from_slice(&[41; 32]).unwrap(),
4315 let counterparty_pubkeys = ChannelPublicKeys {
4316 funding_pubkey: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[44; 32]).unwrap()),
4317 revocation_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[45; 32]).unwrap()),
4318 payment_point: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[46; 32]).unwrap()),
4319 delayed_payment_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[47; 32]).unwrap()),
4320 htlc_basepoint: PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[48; 32]).unwrap())
4322 let funding_outpoint = OutPoint { txid: Txid::all_zeros(), index: u16::max_value() };
4323 let channel_parameters = ChannelTransactionParameters {
4324 holder_pubkeys: keys.holder_channel_pubkeys.clone(),
4325 holder_selected_contest_delay: 66,
4326 is_outbound_from_holder: true,
4327 counterparty_parameters: Some(CounterpartyChannelTransactionParameters {
4328 pubkeys: counterparty_pubkeys,
4329 selected_contest_delay: 67,
4331 funding_outpoint: Some(funding_outpoint),
4332 channel_type_features: ChannelTypeFeatures::only_static_remote_key()
4334 // Prune with one old state and a holder commitment tx holding a few overlaps with the
4336 let shutdown_pubkey = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());
4337 let best_block = BestBlock::from_network(Network::Testnet);
4338 let monitor = ChannelMonitor::new(Secp256k1::new(), keys,
4339 Some(ShutdownScript::new_p2wpkh_from_pubkey(shutdown_pubkey).into_inner()), 0, &Script::new(),
4340 (OutPoint { txid: Txid::from_slice(&[43; 32]).unwrap(), index: 0 }, Script::new()),
4341 &channel_parameters, Script::new(), 46, 0, HolderCommitmentTransaction::dummy(&mut Vec::new()),
4342 best_block, dummy_key);
4344 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..10]);
4345 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4346 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4347 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4348 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"1").into_inner()),
4349 preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
4350 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"2").into_inner()),
4351 preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
4352 for &(ref preimage, ref hash) in preimages.iter() {
4353 let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
4354 monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
4357 // Now provide a secret, pruning preimages 10-15
4358 let mut secret = [0; 32];
4359 secret[0..32].clone_from_slice(&hex::decode("7cc854b54e3e0dcdb010d7a3fee464a9687be6e8db3be6854c475621e007a5dc").unwrap());
4360 monitor.provide_secret(281474976710655, secret.clone()).unwrap();
4361 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 15);
4362 test_preimages_exist!(&preimages[0..10], monitor);
4363 test_preimages_exist!(&preimages[15..20], monitor);
4365 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"3").into_inner()),
4366 preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
4368 // Now provide a further secret, pruning preimages 15-17
4369 secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
4370 monitor.provide_secret(281474976710654, secret.clone()).unwrap();
4371 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 13);
4372 test_preimages_exist!(&preimages[0..10], monitor);
4373 test_preimages_exist!(&preimages[17..20], monitor);
4375 monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"4").into_inner()),
4376 preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
4378 // Now update holder commitment tx info, pruning only element 18 as we still care about the
4379 // previous commitment tx's preimages too
4380 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..5]);
4381 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4382 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx.clone(),
4383 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4384 secret[0..32].clone_from_slice(&hex::decode("2273e227a5b7449b6e70f1fb4652864038b1cbf9cd7c043a7d6456b7fc275ad8").unwrap());
4385 monitor.provide_secret(281474976710653, secret.clone()).unwrap();
4386 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 12);
4387 test_preimages_exist!(&preimages[0..10], monitor);
4388 test_preimages_exist!(&preimages[18..20], monitor);
4390 // But if we do it again, we'll prune 5-10
4391 let mut htlcs = preimages_slice_to_htlcs!(preimages[0..3]);
4392 let dummy_commitment_tx = HolderCommitmentTransaction::dummy(&mut htlcs);
4393 monitor.provide_latest_holder_commitment_tx(dummy_commitment_tx,
4394 htlcs.into_iter().map(|(htlc, _)| (htlc, Some(dummy_sig), None)).collect()).unwrap();
4395 secret[0..32].clone_from_slice(&hex::decode("27cddaa5624534cb6cb9d7da077cf2b22ab21e9b506fd4998a51d54502e99116").unwrap());
4396 monitor.provide_secret(281474976710652, secret.clone()).unwrap();
4397 assert_eq!(monitor.inner.lock().unwrap().payment_preimages.len(), 5);
4398 test_preimages_exist!(&preimages[0..5], monitor);
4402 fn test_claim_txn_weight_computation() {
4403 // We test Claim txn weight, knowing that we want expected weigth and
4404 // not actual case to avoid sigs and time-lock delays hell variances.
4406 let secp_ctx = Secp256k1::new();
4407 let privkey = SecretKey::from_slice(&hex::decode("0101010101010101010101010101010101010101010101010101010101010101").unwrap()[..]).unwrap();
4408 let pubkey = PublicKey::from_secret_key(&secp_ctx, &privkey);
4410 macro_rules! sign_input {
4411 ($sighash_parts: expr, $idx: expr, $amount: expr, $weight: expr, $sum_actual_sigs: expr, $opt_anchors: expr) => {
4412 let htlc = HTLCOutputInCommitment {
4413 offered: if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_offered_htlc($opt_anchors) { true } else { false },
4415 cltv_expiry: 2 << 16,
4416 payment_hash: PaymentHash([1; 32]),
4417 transaction_output_index: Some($idx as u32),
4419 let redeem_script = if *$weight == WEIGHT_REVOKED_OUTPUT { chan_utils::get_revokeable_redeemscript(&pubkey, 256, &pubkey) } else { chan_utils::get_htlc_redeemscript_with_explicit_keys(&htlc, $opt_anchors, &pubkey, &pubkey, &pubkey) };
4420 let sighash = hash_to_message!(&$sighash_parts.segwit_signature_hash($idx, &redeem_script, $amount, EcdsaSighashType::All).unwrap()[..]);
4421 let sig = secp_ctx.sign_ecdsa(&sighash, &privkey);
4422 let mut ser_sig = sig.serialize_der().to_vec();
4423 ser_sig.push(EcdsaSighashType::All as u8);
4424 $sum_actual_sigs += ser_sig.len();
4425 let witness = $sighash_parts.witness_mut($idx).unwrap();
4426 witness.push(ser_sig);
4427 if *$weight == WEIGHT_REVOKED_OUTPUT {
4428 witness.push(vec!(1));
4429 } else if *$weight == weight_revoked_offered_htlc($opt_anchors) || *$weight == weight_revoked_received_htlc($opt_anchors) {
4430 witness.push(pubkey.clone().serialize().to_vec());
4431 } else if *$weight == weight_received_htlc($opt_anchors) {
4432 witness.push(vec![0]);
4434 witness.push(PaymentPreimage([1; 32]).0.to_vec());
4436 witness.push(redeem_script.into_bytes());
4437 let witness = witness.to_vec();
4438 println!("witness[0] {}", witness[0].len());
4439 println!("witness[1] {}", witness[1].len());
4440 println!("witness[2] {}", witness[2].len());
4444 let script_pubkey = Builder::new().push_opcode(opcodes::all::OP_RETURN).into_script();
4445 let txid = Txid::from_hex("56944c5d3f98413ef45cf54545538103cc9f298e0575820ad3591376e2e0f65d").unwrap();
4447 // Justice tx with 1 to_holder, 2 revoked offered HTLCs, 1 revoked received HTLCs
4448 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4449 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4450 let mut sum_actual_sigs = 0;
4452 claim_tx.input.push(TxIn {
4453 previous_output: BitcoinOutPoint {
4457 script_sig: Script::new(),
4458 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4459 witness: Witness::new(),
4462 claim_tx.output.push(TxOut {
4463 script_pubkey: script_pubkey.clone(),
4466 let base_weight = claim_tx.weight();
4467 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT, weight_revoked_offered_htlc(channel_type_features), weight_revoked_offered_htlc(channel_type_features), weight_revoked_received_htlc(channel_type_features)];
4468 let mut inputs_total_weight = 2; // count segwit flags
4470 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4471 for (idx, inp) in inputs_weight.iter().enumerate() {
4472 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4473 inputs_total_weight += inp;
4476 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4479 // Claim tx with 1 offered HTLCs, 3 received HTLCs
4480 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4481 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4482 let mut sum_actual_sigs = 0;
4484 claim_tx.input.push(TxIn {
4485 previous_output: BitcoinOutPoint {
4489 script_sig: Script::new(),
4490 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4491 witness: Witness::new(),
4494 claim_tx.output.push(TxOut {
4495 script_pubkey: script_pubkey.clone(),
4498 let base_weight = claim_tx.weight();
4499 let inputs_weight = vec![weight_offered_htlc(channel_type_features), weight_received_htlc(channel_type_features), weight_received_htlc(channel_type_features), weight_received_htlc(channel_type_features)];
4500 let mut inputs_total_weight = 2; // count segwit flags
4502 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4503 for (idx, inp) in inputs_weight.iter().enumerate() {
4504 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4505 inputs_total_weight += inp;
4508 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_sig */ (73 * inputs_weight.len() - sum_actual_sigs));
4511 // Justice tx with 1 revoked HTLC-Success tx output
4512 for channel_type_features in [ChannelTypeFeatures::only_static_remote_key(), ChannelTypeFeatures::anchors_zero_htlc_fee_and_dependencies()].iter() {
4513 let mut claim_tx = Transaction { version: 0, lock_time: PackedLockTime::ZERO, input: Vec::new(), output: Vec::new() };
4514 let mut sum_actual_sigs = 0;
4515 claim_tx.input.push(TxIn {
4516 previous_output: BitcoinOutPoint {
4520 script_sig: Script::new(),
4521 sequence: Sequence::ENABLE_RBF_NO_LOCKTIME,
4522 witness: Witness::new(),
4524 claim_tx.output.push(TxOut {
4525 script_pubkey: script_pubkey.clone(),
4528 let base_weight = claim_tx.weight();
4529 let inputs_weight = vec![WEIGHT_REVOKED_OUTPUT];
4530 let mut inputs_total_weight = 2; // count segwit flags
4532 let mut sighash_parts = sighash::SighashCache::new(&mut claim_tx);
4533 for (idx, inp) in inputs_weight.iter().enumerate() {
4534 sign_input!(sighash_parts, idx, 0, inp, sum_actual_sigs, channel_type_features);
4535 inputs_total_weight += inp;
4538 assert_eq!(base_weight + inputs_total_weight as usize, claim_tx.weight() + /* max_length_isg */ (73 * inputs_weight.len() - sum_actual_sigs));
4542 // Further testing is done in the ChannelManager integration tests.